diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/3p/chibicc/chibicc.h | 2 | ||||
| -rw-r--r-- | src/3p/chibicc/codegen.c | 1595 | ||||
| -rw-r--r-- | src/3p/chibicc/main.c | 791 | ||||
| -rw-r--r-- | src/3p/chibicc/parse.c | 3368 | ||||
| -rw-r--r-- | src/3p/chibicc/preprocess.c | 1208 | ||||
| -rw-r--r-- | src/3p/chibicc/type.c | 307 | 
6 files changed, 1 insertions, 7270 deletions
diff --git a/src/3p/chibicc/chibicc.h b/src/3p/chibicc/chibicc.h index 1719bc5..82aad11 100644 --- a/src/3p/chibicc/chibicc.h +++ b/src/3p/chibicc/chibicc.h @@ -28,7 +28,7 @@  #include <time.h>  //#include <unistd.h> -// exists on all Unixes but normally hidden _GNU_SOURCE on Linux. +// exists on all Unixes but normally hidden behind _GNU_SOURCE on Linux.  // missing entirely on Windows (implemented in 3p/openbsd/asprintf.c for compat)  int vasprintf(char **str, const char *fmt, va_list ap); diff --git a/src/3p/chibicc/codegen.c b/src/3p/chibicc/codegen.c deleted file mode 100644 index da11fd7..0000000 --- a/src/3p/chibicc/codegen.c +++ /dev/null @@ -1,1595 +0,0 @@ -#include "chibicc.h" - -#define GP_MAX 6 -#define FP_MAX 8 - -static FILE *output_file; -static int depth; -static char *argreg8[] = {"%dil", "%sil", "%dl", "%cl", "%r8b", "%r9b"}; -static char *argreg16[] = {"%di", "%si", "%dx", "%cx", "%r8w", "%r9w"}; -static char *argreg32[] = {"%edi", "%esi", "%edx", "%ecx", "%r8d", "%r9d"}; -static char *argreg64[] = {"%rdi", "%rsi", "%rdx", "%rcx", "%r8", "%r9"}; -static Obj *current_fn; - -static void gen_expr(Node *node); -static void gen_stmt(Node *node); - -__attribute__((format(printf, 1, 2))) -static void println(char *fmt, ...) { -  va_list ap; -  va_start(ap, fmt); -  vfprintf(output_file, fmt, ap); -  va_end(ap); -  fprintf(output_file, "\n"); -} - -static int count(void) { -  static int i = 1; -  return i++; -} - -static void push(void) { -  println("  push %%rax"); -  depth++; -} - -static void pop(char *arg) { -  println("  pop %s", arg); -  depth--; -} - -static void pushf(void) { -  println("  sub $8, %%rsp"); -  println("  movsd %%xmm0, (%%rsp)"); -  depth++; -} - -static void popf(int reg) { -  println("  movsd (%%rsp), %%xmm%d", reg); -  println("  add $8, %%rsp"); -  depth--; -} - -// Round up `n` to the nearest multiple of `align`. For instance, -// align_to(5, 8) returns 8 and align_to(11, 8) returns 16. -int align_to(int n, int align) { -  return (n + align - 1) / align * align; -} - -static char *reg_dx(int sz) { -  switch (sz) { -  case 1: return "%dl"; -  case 2: return "%dx"; -  case 4: return "%edx"; -  case 8: return "%rdx"; -  } -  unreachable(); -} - -static char *reg_ax(int sz) { -  switch (sz) { -  case 1: return "%al"; -  case 2: return "%ax"; -  case 4: return "%eax"; -  case 8: return "%rax"; -  } -  unreachable(); -} - -// Compute the absolute address of a given node. -// It's an error if a given node does not reside in memory. -static void gen_addr(Node *node) { -  switch (node->kind) { -  case ND_VAR: -    // Variable-length array, which is always local. -    if (node->var->ty->kind == TY_VLA) { -      println("  mov %d(%%rbp), %%rax", node->var->offset); -      return; -    } - -    // Local variable -    if (node->var->is_local) { -      println("  lea %d(%%rbp), %%rax", node->var->offset); -      return; -    } - -    if (opt_fpic) { -      // Thread-local variable -      if (node->var->is_tls) { -        println("  data16 lea %s@tlsgd(%%rip), %%rdi", node->var->name); -        println("  .value 0x6666"); -        println("  rex64"); -        println("  call __tls_get_addr@PLT"); -        return; -      } - -      // Function or global variable -      println("  mov %s@GOTPCREL(%%rip), %%rax", node->var->name); -      return; -    } - -    // Thread-local variable -    if (node->var->is_tls) { -      println("  mov %%fs:0, %%rax"); -      println("  add $%s@tpoff, %%rax", node->var->name); -      return; -    } - -    // Here, we generate an absolute address of a function or a global -    // variable. Even though they exist at a certain address at runtime, -    // their addresses are not known at link-time for the following -    // two reasons. -    // -    //  - Address randomization: Executables are loaded to memory as a -    //    whole but it is not known what address they are loaded to. -    //    Therefore, at link-time, relative address in the same -    //    exectuable (i.e. the distance between two functions in the -    //    same executable) is known, but the absolute address is not -    //    known. -    // -    //  - Dynamic linking: Dynamic shared objects (DSOs) or .so files -    //    are loaded to memory alongside an executable at runtime and -    //    linked by the runtime loader in memory. We know nothing -    //    about addresses of global stuff that may be defined by DSOs -    //    until the runtime relocation is complete. -    // -    // In order to deal with the former case, we use RIP-relative -    // addressing, denoted by `(%rip)`. For the latter, we obtain an -    // address of a stuff that may be in a shared object file from the -    // Global Offset Table using `@GOTPCREL(%rip)` notation. - -    // Function -    if (node->ty->kind == TY_FUNC) { -      if (node->var->is_definition) -        println("  lea %s(%%rip), %%rax", node->var->name); -      else -        println("  mov %s@GOTPCREL(%%rip), %%rax", node->var->name); -      return; -    } - -    // Global variable -    println("  lea %s(%%rip), %%rax", node->var->name); -    return; -  case ND_DEREF: -    gen_expr(node->lhs); -    return; -  case ND_COMMA: -    gen_expr(node->lhs); -    gen_addr(node->rhs); -    return; -  case ND_MEMBER: -    gen_addr(node->lhs); -    println("  add $%d, %%rax", node->member->offset); -    return; -  case ND_FUNCALL: -    if (node->ret_buffer) { -      gen_expr(node); -      return; -    } -    break; -  case ND_ASSIGN: -  case ND_COND: -    if (node->ty->kind == TY_STRUCT || node->ty->kind == TY_UNION) { -      gen_expr(node); -      return; -    } -    break; -  case ND_VLA_PTR: -    println("  lea %d(%%rbp), %%rax", node->var->offset); -    return; -  } - -  error_tok(node->tok, "not an lvalue"); -} - -// Load a value from where %rax is pointing to. -static void load(Type *ty) { -  switch (ty->kind) { -  case TY_ARRAY: -  case TY_STRUCT: -  case TY_UNION: -  case TY_FUNC: -  case TY_VLA: -    // If it is an array, do not attempt to load a value to the -    // register because in general we can't load an entire array to a -    // register. As a result, the result of an evaluation of an array -    // becomes not the array itself but the address of the array. -    // This is where "array is automatically converted to a pointer to -    // the first element of the array in C" occurs. -    return; -  case TY_FLOAT: -    println("  movss (%%rax), %%xmm0"); -    return; -  case TY_DOUBLE: -    println("  movsd (%%rax), %%xmm0"); -    return; -  case TY_LDOUBLE: -    println("  fldt (%%rax)"); -    return; -  } - -  char *insn = ty->is_unsigned ? "movz" : "movs"; - -  // When we load a char or a short value to a register, we always -  // extend them to the size of int, so we can assume the lower half of -  // a register always contains a valid value. The upper half of a -  // register for char, short and int may contain garbage. When we load -  // a long value to a register, it simply occupies the entire register. -  if (ty->size == 1) -    println("  %sbl (%%rax), %%eax", insn); -  else if (ty->size == 2) -    println("  %swl (%%rax), %%eax", insn); -  else if (ty->size == 4) -    println("  movsxd (%%rax), %%rax"); -  else -    println("  mov (%%rax), %%rax"); -} - -// Store %rax to an address that the stack top is pointing to. -static void store(Type *ty) { -  pop("%rdi"); - -  switch (ty->kind) { -  case TY_STRUCT: -  case TY_UNION: -    for (int i = 0; i < ty->size; i++) { -      println("  mov %d(%%rax), %%r8b", i); -      println("  mov %%r8b, %d(%%rdi)", i); -    } -    return; -  case TY_FLOAT: -    println("  movss %%xmm0, (%%rdi)"); -    return; -  case TY_DOUBLE: -    println("  movsd %%xmm0, (%%rdi)"); -    return; -  case TY_LDOUBLE: -    println("  fstpt (%%rdi)"); -    return; -  } - -  if (ty->size == 1) -    println("  mov %%al, (%%rdi)"); -  else if (ty->size == 2) -    println("  mov %%ax, (%%rdi)"); -  else if (ty->size == 4) -    println("  mov %%eax, (%%rdi)"); -  else -    println("  mov %%rax, (%%rdi)"); -} - -static void cmp_zero(Type *ty) { -  switch (ty->kind) { -  case TY_FLOAT: -    println("  xorps %%xmm1, %%xmm1"); -    println("  ucomiss %%xmm1, %%xmm0"); -    return; -  case TY_DOUBLE: -    println("  xorpd %%xmm1, %%xmm1"); -    println("  ucomisd %%xmm1, %%xmm0"); -    return; -  case TY_LDOUBLE: -    println("  fldz"); -    println("  fucomip"); -    println("  fstp %%st(0)"); -    return; -  } - -  if (is_integer(ty) && ty->size <= 4) -    println("  cmp $0, %%eax"); -  else -    println("  cmp $0, %%rax"); -} - -enum { I8, I16, I32, I64, U8, U16, U32, U64, F32, F64, F80 }; - -static int getTypeId(Type *ty) { -  switch (ty->kind) { -  case TY_CHAR: -    return ty->is_unsigned ? U8 : I8; -  case TY_SHORT: -    return ty->is_unsigned ? U16 : I16; -  case TY_INT: -    return ty->is_unsigned ? U32 : I32; -  case TY_LONG: -    return ty->is_unsigned ? U64 : I64; -  case TY_FLOAT: -    return F32; -  case TY_DOUBLE: -    return F64; -  case TY_LDOUBLE: -    return F80; -  } -  return U64; -} - -// The table for type casts -static char i32i8[] = "movsbl %al, %eax"; -static char i32u8[] = "movzbl %al, %eax"; -static char i32i16[] = "movswl %ax, %eax"; -static char i32u16[] = "movzwl %ax, %eax"; -static char i32f32[] = "cvtsi2ssl %eax, %xmm0"; -static char i32i64[] = "movsxd %eax, %rax"; -static char i32f64[] = "cvtsi2sdl %eax, %xmm0"; -static char i32f80[] = "mov %eax, -4(%rsp); fildl -4(%rsp)"; - -static char u32f32[] = "mov %eax, %eax; cvtsi2ssq %rax, %xmm0"; -static char u32i64[] = "mov %eax, %eax"; -static char u32f64[] = "mov %eax, %eax; cvtsi2sdq %rax, %xmm0"; -static char u32f80[] = "mov %eax, %eax; mov %rax, -8(%rsp); fildll -8(%rsp)"; - -static char i64f32[] = "cvtsi2ssq %rax, %xmm0"; -static char i64f64[] = "cvtsi2sdq %rax, %xmm0"; -static char i64f80[] = "movq %rax, -8(%rsp); fildll -8(%rsp)"; - -static char u64f32[] = "cvtsi2ssq %rax, %xmm0"; -static char u64f64[] = -  "test %rax,%rax; js 1f; pxor %xmm0,%xmm0; cvtsi2sd %rax,%xmm0; jmp 2f; " -  "1: mov %rax,%rdi; and $1,%eax; pxor %xmm0,%xmm0; shr %rdi; " -  "or %rax,%rdi; cvtsi2sd %rdi,%xmm0; addsd %xmm0,%xmm0; 2:"; -static char u64f80[] = -  "mov %rax, -8(%rsp); fildq -8(%rsp); test %rax, %rax; jns 1f;" -  "mov $1602224128, %eax; mov %eax, -4(%rsp); fadds -4(%rsp); 1:"; - -static char f32i8[] = "cvttss2sil %xmm0, %eax; movsbl %al, %eax"; -static char f32u8[] = "cvttss2sil %xmm0, %eax; movzbl %al, %eax"; -static char f32i16[] = "cvttss2sil %xmm0, %eax; movswl %ax, %eax"; -static char f32u16[] = "cvttss2sil %xmm0, %eax; movzwl %ax, %eax"; -static char f32i32[] = "cvttss2sil %xmm0, %eax"; -static char f32u32[] = "cvttss2siq %xmm0, %rax"; -static char f32i64[] = "cvttss2siq %xmm0, %rax"; -static char f32u64[] = "cvttss2siq %xmm0, %rax"; -static char f32f64[] = "cvtss2sd %xmm0, %xmm0"; -static char f32f80[] = "movss %xmm0, -4(%rsp); flds -4(%rsp)"; - -static char f64i8[] = "cvttsd2sil %xmm0, %eax; movsbl %al, %eax"; -static char f64u8[] = "cvttsd2sil %xmm0, %eax; movzbl %al, %eax"; -static char f64i16[] = "cvttsd2sil %xmm0, %eax; movswl %ax, %eax"; -static char f64u16[] = "cvttsd2sil %xmm0, %eax; movzwl %ax, %eax"; -static char f64i32[] = "cvttsd2sil %xmm0, %eax"; -static char f64u32[] = "cvttsd2siq %xmm0, %rax"; -static char f64i64[] = "cvttsd2siq %xmm0, %rax"; -static char f64u64[] = "cvttsd2siq %xmm0, %rax"; -static char f64f32[] = "cvtsd2ss %xmm0, %xmm0"; -static char f64f80[] = "movsd %xmm0, -8(%rsp); fldl -8(%rsp)"; - -#define FROM_F80_1                                           \ -  "fnstcw -10(%rsp); movzwl -10(%rsp), %eax; or $12, %ah; " \ -  "mov %ax, -12(%rsp); fldcw -12(%rsp); " - -#define FROM_F80_2 " -24(%rsp); fldcw -10(%rsp); " - -static char f80i8[] = FROM_F80_1 "fistps" FROM_F80_2 "movsbl -24(%rsp), %eax"; -static char f80u8[] = FROM_F80_1 "fistps" FROM_F80_2 "movzbl -24(%rsp), %eax"; -static char f80i16[] = FROM_F80_1 "fistps" FROM_F80_2 "movzbl -24(%rsp), %eax"; -static char f80u16[] = FROM_F80_1 "fistpl" FROM_F80_2 "movswl -24(%rsp), %eax"; -static char f80i32[] = FROM_F80_1 "fistpl" FROM_F80_2 "mov -24(%rsp), %eax"; -static char f80u32[] = FROM_F80_1 "fistpl" FROM_F80_2 "mov -24(%rsp), %eax"; -static char f80i64[] = FROM_F80_1 "fistpq" FROM_F80_2 "mov -24(%rsp), %rax"; -static char f80u64[] = FROM_F80_1 "fistpq" FROM_F80_2 "mov -24(%rsp), %rax"; -static char f80f32[] = "fstps -8(%rsp); movss -8(%rsp), %xmm0"; -static char f80f64[] = "fstpl -8(%rsp); movsd -8(%rsp), %xmm0"; - -static char *cast_table[][11] = { -  // i8   i16     i32     i64     u8     u16     u32     u64     f32     f64     f80 -  {NULL,  NULL,   NULL,   i32i64, i32u8, i32u16, NULL,   i32i64, i32f32, i32f64, i32f80}, // i8 -  {i32i8, NULL,   NULL,   i32i64, i32u8, i32u16, NULL,   i32i64, i32f32, i32f64, i32f80}, // i16 -  {i32i8, i32i16, NULL,   i32i64, i32u8, i32u16, NULL,   i32i64, i32f32, i32f64, i32f80}, // i32 -  {i32i8, i32i16, NULL,   NULL,   i32u8, i32u16, NULL,   NULL,   i64f32, i64f64, i64f80}, // i64 - -  {i32i8, NULL,   NULL,   i32i64, NULL,  NULL,   NULL,   i32i64, i32f32, i32f64, i32f80}, // u8 -  {i32i8, i32i16, NULL,   i32i64, i32u8, NULL,   NULL,   i32i64, i32f32, i32f64, i32f80}, // u16 -  {i32i8, i32i16, NULL,   u32i64, i32u8, i32u16, NULL,   u32i64, u32f32, u32f64, u32f80}, // u32 -  {i32i8, i32i16, NULL,   NULL,   i32u8, i32u16, NULL,   NULL,   u64f32, u64f64, u64f80}, // u64 - -  {f32i8, f32i16, f32i32, f32i64, f32u8, f32u16, f32u32, f32u64, NULL,   f32f64, f32f80}, // f32 -  {f64i8, f64i16, f64i32, f64i64, f64u8, f64u16, f64u32, f64u64, f64f32, NULL,   f64f80}, // f64 -  {f80i8, f80i16, f80i32, f80i64, f80u8, f80u16, f80u32, f80u64, f80f32, f80f64, NULL},   // f80 -}; - -static void cast(Type *from, Type *to) { -  if (to->kind == TY_VOID) -    return; - -  if (to->kind == TY_BOOL) { -    cmp_zero(from); -    println("  setne %%al"); -    println("  movzx %%al, %%eax"); -    return; -  } - -  int t1 = getTypeId(from); -  int t2 = getTypeId(to); -  if (cast_table[t1][t2]) -    println("  %s", cast_table[t1][t2]); -} - -// Structs or unions equal or smaller than 16 bytes are passed -// using up to two registers. -// -// If the first 8 bytes contains only floating-point type members, -// they are passed in an XMM register. Otherwise, they are passed -// in a general-purpose register. -// -// If a struct/union is larger than 8 bytes, the same rule is -// applied to the the next 8 byte chunk. -// -// This function returns true if `ty` has only floating-point -// members in its byte range [lo, hi). -static bool has_flonum(Type *ty, int lo, int hi, int offset) { -  if (ty->kind == TY_STRUCT || ty->kind == TY_UNION) { -    for (Member *mem = ty->members; mem; mem = mem->next) -      if (!has_flonum(mem->ty, lo, hi, offset + mem->offset)) -        return false; -    return true; -  } - -  if (ty->kind == TY_ARRAY) { -    for (int i = 0; i < ty->array_len; i++) -      if (!has_flonum(ty->base, lo, hi, offset + ty->base->size * i)) -        return false; -    return true; -  } - -  return offset < lo || hi <= offset || ty->kind == TY_FLOAT || ty->kind == TY_DOUBLE; -} - -static bool has_flonum1(Type *ty) { -  return has_flonum(ty, 0, 8, 0); -} - -static bool has_flonum2(Type *ty) { -  return has_flonum(ty, 8, 16, 0); -} - -static void push_struct(Type *ty) { -  int sz = align_to(ty->size, 8); -  println("  sub $%d, %%rsp", sz); -  depth += sz / 8; - -  for (int i = 0; i < ty->size; i++) { -    println("  mov %d(%%rax), %%r10b", i); -    println("  mov %%r10b, %d(%%rsp)", i); -  } -} - -static void push_args2(Node *args, bool first_pass) { -  if (!args) -    return; -  push_args2(args->next, first_pass); - -  if ((first_pass && !args->pass_by_stack) || (!first_pass && args->pass_by_stack)) -    return; - -  gen_expr(args); - -  switch (args->ty->kind) { -  case TY_STRUCT: -  case TY_UNION: -    push_struct(args->ty); -    break; -  case TY_FLOAT: -  case TY_DOUBLE: -    pushf(); -    break; -  case TY_LDOUBLE: -    println("  sub $16, %%rsp"); -    println("  fstpt (%%rsp)"); -    depth += 2; -    break; -  default: -    push(); -  } -} - -// Load function call arguments. Arguments are already evaluated and -// stored to the stack as local variables. What we need to do in this -// function is to load them to registers or push them to the stack as -// specified by the x86-64 psABI. Here is what the spec says: -// -// - Up to 6 arguments of integral type are passed using RDI, RSI, -//   RDX, RCX, R8 and R9. -// -// - Up to 8 arguments of floating-point type are passed using XMM0 to -//   XMM7. -// -// - If all registers of an appropriate type are already used, push an -//   argument to the stack in the right-to-left order. -// -// - Each argument passed on the stack takes 8 bytes, and the end of -//   the argument area must be aligned to a 16 byte boundary. -// -// - If a function is variadic, set the number of floating-point type -//   arguments to RAX. -static int push_args(Node *node) { -  int stack = 0, gp = 0, fp = 0; - -  // If the return type is a large struct/union, the caller passes -  // a pointer to a buffer as if it were the first argument. -  if (node->ret_buffer && node->ty->size > 16) -    gp++; - -  // Load as many arguments to the registers as possible. -  for (Node *arg = node->args; arg; arg = arg->next) { -    Type *ty = arg->ty; - -    switch (ty->kind) { -    case TY_STRUCT: -    case TY_UNION: -      if (ty->size > 16) { -        arg->pass_by_stack = true; -        stack += align_to(ty->size, 8) / 8; -      } else { -        bool fp1 = has_flonum1(ty); -        bool fp2 = has_flonum2(ty); - -        if (fp + fp1 + fp2 < FP_MAX && gp + !fp1 + !fp2 < GP_MAX) { -          fp = fp + fp1 + fp2; -          gp = gp + !fp1 + !fp2; -        } else { -          arg->pass_by_stack = true; -          stack += align_to(ty->size, 8) / 8; -        } -      } -      break; -    case TY_FLOAT: -    case TY_DOUBLE: -      if (fp++ >= FP_MAX) { -        arg->pass_by_stack = true; -        stack++; -      } -      break; -    case TY_LDOUBLE: -      arg->pass_by_stack = true; -      stack += 2; -      break; -    default: -      if (gp++ >= GP_MAX) { -        arg->pass_by_stack = true; -        stack++; -      } -    } -  } - -  if ((depth + stack) % 2 == 1) { -    println("  sub $8, %%rsp"); -    depth++; -    stack++; -  } - -  push_args2(node->args, true); -  push_args2(node->args, false); - -  // If the return type is a large struct/union, the caller passes -  // a pointer to a buffer as if it were the first argument. -  if (node->ret_buffer && node->ty->size > 16) { -    println("  lea %d(%%rbp), %%rax", node->ret_buffer->offset); -    push(); -  } - -  return stack; -} - -static void copy_ret_buffer(Obj *var) { -  Type *ty = var->ty; -  int gp = 0, fp = 0; - -  if (has_flonum1(ty)) { -    assert(ty->size == 4 || 8 <= ty->size); -    if (ty->size == 4) -      println("  movss %%xmm0, %d(%%rbp)", var->offset); -    else -      println("  movsd %%xmm0, %d(%%rbp)", var->offset); -    fp++; -  } else { -    for (int i = 0; i < MIN(8, ty->size); i++) { -      println("  mov %%al, %d(%%rbp)", var->offset + i); -      println("  shr $8, %%rax"); -    } -    gp++; -  } - -  if (ty->size > 8) { -    if (has_flonum2(ty)) { -      assert(ty->size == 12 || ty->size == 16); -      if (ty->size == 12) -        println("  movss %%xmm%d, %d(%%rbp)", fp, var->offset + 8); -      else -        println("  movsd %%xmm%d, %d(%%rbp)", fp, var->offset + 8); -    } else { -      char *reg1 = (gp == 0) ? "%al" : "%dl"; -      char *reg2 = (gp == 0) ? "%rax" : "%rdx"; -      for (int i = 8; i < MIN(16, ty->size); i++) { -        println("  mov %s, %d(%%rbp)", reg1, var->offset + i); -        println("  shr $8, %s", reg2); -      } -    } -  } -} - -static void copy_struct_reg(void) { -  Type *ty = current_fn->ty->return_ty; -  int gp = 0, fp = 0; - -  println("  mov %%rax, %%rdi"); - -  if (has_flonum(ty, 0, 8, 0)) { -    assert(ty->size == 4 || 8 <= ty->size); -    if (ty->size == 4) -      println("  movss (%%rdi), %%xmm0"); -    else -      println("  movsd (%%rdi), %%xmm0"); -    fp++; -  } else { -    println("  mov $0, %%rax"); -    for (int i = MIN(8, ty->size) - 1; i >= 0; i--) { -      println("  shl $8, %%rax"); -      println("  mov %d(%%rdi), %%al", i); -    } -    gp++; -  } - -  if (ty->size > 8) { -    if (has_flonum(ty, 8, 16, 0)) { -      assert(ty->size == 12 || ty->size == 16); -      if (ty->size == 4) -        println("  movss 8(%%rdi), %%xmm%d", fp); -      else -        println("  movsd 8(%%rdi), %%xmm%d", fp); -    } else { -      char *reg1 = (gp == 0) ? "%al" : "%dl"; -      char *reg2 = (gp == 0) ? "%rax" : "%rdx"; -      println("  mov $0, %s", reg2); -      for (int i = MIN(16, ty->size) - 1; i >= 8; i--) { -        println("  shl $8, %s", reg2); -        println("  mov %d(%%rdi), %s", i, reg1); -      } -    } -  } -} - -static void copy_struct_mem(void) { -  Type *ty = current_fn->ty->return_ty; -  Obj *var = current_fn->params; - -  println("  mov %d(%%rbp), %%rdi", var->offset); - -  for (int i = 0; i < ty->size; i++) { -    println("  mov %d(%%rax), %%dl", i); -    println("  mov %%dl, %d(%%rdi)", i); -  } -} - -static void builtin_alloca(void) { -  // Align size to 16 bytes. -  println("  add $15, %%rdi"); -  println("  and $0xfffffff0, %%edi"); - -  // Shift the temporary area by %rdi. -  println("  mov %d(%%rbp), %%rcx", current_fn->alloca_bottom->offset); -  println("  sub %%rsp, %%rcx"); -  println("  mov %%rsp, %%rax"); -  println("  sub %%rdi, %%rsp"); -  println("  mov %%rsp, %%rdx"); -  println("1:"); -  println("  cmp $0, %%rcx"); -  println("  je 2f"); -  println("  mov (%%rax), %%r8b"); -  println("  mov %%r8b, (%%rdx)"); -  println("  inc %%rdx"); -  println("  inc %%rax"); -  println("  dec %%rcx"); -  println("  jmp 1b"); -  println("2:"); - -  // Move alloca_bottom pointer. -  println("  mov %d(%%rbp), %%rax", current_fn->alloca_bottom->offset); -  println("  sub %%rdi, %%rax"); -  println("  mov %%rax, %d(%%rbp)", current_fn->alloca_bottom->offset); -} - -// Generate code for a given node. -static void gen_expr(Node *node) { -  println("  .loc %d %d", node->tok->file->file_no, node->tok->line_no); - -  switch (node->kind) { -  case ND_NULL_EXPR: -    return; -  case ND_NUM: { -    switch (node->ty->kind) { -    case TY_FLOAT: { -      union { float f32; uint32_t u32; } u = { node->fval }; -      println("  mov $%u, %%eax  # float %Lf", u.u32, node->fval); -      println("  movq %%rax, %%xmm0"); -      return; -    } -    case TY_DOUBLE: { -      union { double f64; uint64_t u64; } u = { node->fval }; -      println("  mov $%lu, %%rax  # double %Lf", u.u64, node->fval); -      println("  movq %%rax, %%xmm0"); -      return; -    } -    case TY_LDOUBLE: { -      union { long double f80; uint64_t u64[2]; } u; -      memset(&u, 0, sizeof(u)); -      u.f80 = node->fval; -      println("  mov $%lu, %%rax  # long double %Lf", u.u64[0], node->fval); -      println("  mov %%rax, -16(%%rsp)"); -      println("  mov $%lu, %%rax", u.u64[1]); -      println("  mov %%rax, -8(%%rsp)"); -      println("  fldt -16(%%rsp)"); -      return; -    } -    } - -    println("  mov $%ld, %%rax", node->val); -    return; -  } -  case ND_NEG: -    gen_expr(node->lhs); - -    switch (node->ty->kind) { -    case TY_FLOAT: -      println("  mov $1, %%rax"); -      println("  shl $31, %%rax"); -      println("  movq %%rax, %%xmm1"); -      println("  xorps %%xmm1, %%xmm0"); -      return; -    case TY_DOUBLE: -      println("  mov $1, %%rax"); -      println("  shl $63, %%rax"); -      println("  movq %%rax, %%xmm1"); -      println("  xorpd %%xmm1, %%xmm0"); -      return; -    case TY_LDOUBLE: -      println("  fchs"); -      return; -    } - -    println("  neg %%rax"); -    return; -  case ND_VAR: -    gen_addr(node); -    load(node->ty); -    return; -  case ND_MEMBER: { -    gen_addr(node); -    load(node->ty); - -    Member *mem = node->member; -    if (mem->is_bitfield) { -      println("  shl $%d, %%rax", 64 - mem->bit_width - mem->bit_offset); -      if (mem->ty->is_unsigned) -        println("  shr $%d, %%rax", 64 - mem->bit_width); -      else -        println("  sar $%d, %%rax", 64 - mem->bit_width); -    } -    return; -  } -  case ND_DEREF: -    gen_expr(node->lhs); -    load(node->ty); -    return; -  case ND_ADDR: -    gen_addr(node->lhs); -    return; -  case ND_ASSIGN: -    gen_addr(node->lhs); -    push(); -    gen_expr(node->rhs); - -    if (node->lhs->kind == ND_MEMBER && node->lhs->member->is_bitfield) { -      println("  mov %%rax, %%r8"); - -      // If the lhs is a bitfield, we need to read the current value -      // from memory and merge it with a new value. -      Member *mem = node->lhs->member; -      println("  mov %%rax, %%rdi"); -      println("  and $%ld, %%rdi", (1L << mem->bit_width) - 1); -      println("  shl $%d, %%rdi", mem->bit_offset); - -      println("  mov (%%rsp), %%rax"); -      load(mem->ty); - -      long mask = ((1L << mem->bit_width) - 1) << mem->bit_offset; -      println("  mov $%ld, %%r9", ~mask); -      println("  and %%r9, %%rax"); -      println("  or %%rdi, %%rax"); -      store(node->ty); -      println("  mov %%r8, %%rax"); -      return; -    } - -    store(node->ty); -    return; -  case ND_STMT_EXPR: -    for (Node *n = node->body; n; n = n->next) -      gen_stmt(n); -    return; -  case ND_COMMA: -    gen_expr(node->lhs); -    gen_expr(node->rhs); -    return; -  case ND_CAST: -    gen_expr(node->lhs); -    cast(node->lhs->ty, node->ty); -    return; -  case ND_MEMZERO: -    // `rep stosb` is equivalent to `memset(%rdi, %al, %rcx)`. -    println("  mov $%d, %%rcx", node->var->ty->size); -    println("  lea %d(%%rbp), %%rdi", node->var->offset); -    println("  mov $0, %%al"); -    println("  rep stosb"); -    return; -  case ND_COND: { -    int c = count(); -    gen_expr(node->cond); -    cmp_zero(node->cond->ty); -    println("  je .L.else.%d", c); -    gen_expr(node->then); -    println("  jmp .L.end.%d", c); -    println(".L.else.%d:", c); -    gen_expr(node->els); -    println(".L.end.%d:", c); -    return; -  } -  case ND_NOT: -    gen_expr(node->lhs); -    cmp_zero(node->lhs->ty); -    println("  sete %%al"); -    println("  movzx %%al, %%rax"); -    return; -  case ND_BITNOT: -    gen_expr(node->lhs); -    println("  not %%rax"); -    return; -  case ND_LOGAND: { -    int c = count(); -    gen_expr(node->lhs); -    cmp_zero(node->lhs->ty); -    println("  je .L.false.%d", c); -    gen_expr(node->rhs); -    cmp_zero(node->rhs->ty); -    println("  je .L.false.%d", c); -    println("  mov $1, %%rax"); -    println("  jmp .L.end.%d", c); -    println(".L.false.%d:", c); -    println("  mov $0, %%rax"); -    println(".L.end.%d:", c); -    return; -  } -  case ND_LOGOR: { -    int c = count(); -    gen_expr(node->lhs); -    cmp_zero(node->lhs->ty); -    println("  jne .L.true.%d", c); -    gen_expr(node->rhs); -    cmp_zero(node->rhs->ty); -    println("  jne .L.true.%d", c); -    println("  mov $0, %%rax"); -    println("  jmp .L.end.%d", c); -    println(".L.true.%d:", c); -    println("  mov $1, %%rax"); -    println(".L.end.%d:", c); -    return; -  } -  case ND_FUNCALL: { -    if (node->lhs->kind == ND_VAR && !strcmp(node->lhs->var->name, "alloca")) { -      gen_expr(node->args); -      println("  mov %%rax, %%rdi"); -      builtin_alloca(); -      return; -    } - -    int stack_args = push_args(node); -    gen_expr(node->lhs); - -    int gp = 0, fp = 0; - -    // If the return type is a large struct/union, the caller passes -    // a pointer to a buffer as if it were the first argument. -    if (node->ret_buffer && node->ty->size > 16) -      pop(argreg64[gp++]); - -    for (Node *arg = node->args; arg; arg = arg->next) { -      Type *ty = arg->ty; - -      switch (ty->kind) { -      case TY_STRUCT: -      case TY_UNION: -        if (ty->size > 16) -          continue; - -        bool fp1 = has_flonum1(ty); -        bool fp2 = has_flonum2(ty); - -        if (fp + fp1 + fp2 < FP_MAX && gp + !fp1 + !fp2 < GP_MAX) { -          if (fp1) -            popf(fp++); -          else -            pop(argreg64[gp++]); - -          if (ty->size > 8) { -            if (fp2) -              popf(fp++); -            else -              pop(argreg64[gp++]); -          } -        } -        break; -      case TY_FLOAT: -      case TY_DOUBLE: -        if (fp < FP_MAX) -          popf(fp++); -        break; -      case TY_LDOUBLE: -        break; -      default: -        if (gp < GP_MAX) -          pop(argreg64[gp++]); -      } -    } - -    println("  mov %%rax, %%r10"); -    println("  mov $%d, %%rax", fp); -    println("  call *%%r10"); -    println("  add $%d, %%rsp", stack_args * 8); - -    depth -= stack_args; - -    // It looks like the most significant 48 or 56 bits in RAX may -    // contain garbage if a function return type is short or bool/char, -    // respectively. We clear the upper bits here. -    switch (node->ty->kind) { -    case TY_BOOL: -      println("  movzx %%al, %%eax"); -      return; -    case TY_CHAR: -      if (node->ty->is_unsigned) -        println("  movzbl %%al, %%eax"); -      else -        println("  movsbl %%al, %%eax"); -      return; -    case TY_SHORT: -      if (node->ty->is_unsigned) -        println("  movzwl %%ax, %%eax"); -      else -        println("  movswl %%ax, %%eax"); -      return; -    } - -    // If the return type is a small struct, a value is returned -    // using up to two registers. -    if (node->ret_buffer && node->ty->size <= 16) { -      copy_ret_buffer(node->ret_buffer); -      println("  lea %d(%%rbp), %%rax", node->ret_buffer->offset); -    } - -    return; -  } -  case ND_LABEL_VAL: -    println("  lea %s(%%rip), %%rax", node->unique_label); -    return; -  case ND_CAS: { -    gen_expr(node->cas_addr); -    push(); -    gen_expr(node->cas_new); -    push(); -    gen_expr(node->cas_old); -    println("  mov %%rax, %%r8"); -    load(node->cas_old->ty->base); -    pop("%rdx"); // new -    pop("%rdi"); // addr - -    int sz = node->cas_addr->ty->base->size; -    println("  lock cmpxchg %s, (%%rdi)", reg_dx(sz)); -    println("  sete %%cl"); -    println("  je 1f"); -    println("  mov %s, (%%r8)", reg_ax(sz)); -    println("1:"); -    println("  movzbl %%cl, %%eax"); -    return; -  } -  case ND_EXCH: { -    gen_expr(node->lhs); -    push(); -    gen_expr(node->rhs); -    pop("%rdi"); - -    int sz = node->lhs->ty->base->size; -    println("  xchg %s, (%%rdi)", reg_ax(sz)); -    return; -  } -  } - -  switch (node->lhs->ty->kind) { -  case TY_FLOAT: -  case TY_DOUBLE: { -    gen_expr(node->rhs); -    pushf(); -    gen_expr(node->lhs); -    popf(1); - -    char *sz = (node->lhs->ty->kind == TY_FLOAT) ? "ss" : "sd"; - -    switch (node->kind) { -    case ND_ADD: -      println("  add%s %%xmm1, %%xmm0", sz); -      return; -    case ND_SUB: -      println("  sub%s %%xmm1, %%xmm0", sz); -      return; -    case ND_MUL: -      println("  mul%s %%xmm1, %%xmm0", sz); -      return; -    case ND_DIV: -      println("  div%s %%xmm1, %%xmm0", sz); -      return; -    case ND_EQ: -    case ND_NE: -    case ND_LT: -    case ND_LE: -      println("  ucomi%s %%xmm0, %%xmm1", sz); - -      if (node->kind == ND_EQ) { -        println("  sete %%al"); -        println("  setnp %%dl"); -        println("  and %%dl, %%al"); -      } else if (node->kind == ND_NE) { -        println("  setne %%al"); -        println("  setp %%dl"); -        println("  or %%dl, %%al"); -      } else if (node->kind == ND_LT) { -        println("  seta %%al"); -      } else { -        println("  setae %%al"); -      } - -      println("  and $1, %%al"); -      println("  movzb %%al, %%rax"); -      return; -    } - -    error_tok(node->tok, "invalid expression"); -  } -  case TY_LDOUBLE: { -    gen_expr(node->lhs); -    gen_expr(node->rhs); - -    switch (node->kind) { -    case ND_ADD: -      println("  faddp"); -      return; -    case ND_SUB: -      println("  fsubrp"); -      return; -    case ND_MUL: -      println("  fmulp"); -      return; -    case ND_DIV: -      println("  fdivrp"); -      return; -    case ND_EQ: -    case ND_NE: -    case ND_LT: -    case ND_LE: -      println("  fcomip"); -      println("  fstp %%st(0)"); - -      if (node->kind == ND_EQ) -        println("  sete %%al"); -      else if (node->kind == ND_NE) -        println("  setne %%al"); -      else if (node->kind == ND_LT) -        println("  seta %%al"); -      else -        println("  setae %%al"); - -      println("  movzb %%al, %%rax"); -      return; -    } - -    error_tok(node->tok, "invalid expression"); -  } -  } - -  gen_expr(node->rhs); -  push(); -  gen_expr(node->lhs); -  pop("%rdi"); - -  char *ax, *di, *dx; - -  if (node->lhs->ty->kind == TY_LONG || node->lhs->ty->base) { -    ax = "%rax"; -    di = "%rdi"; -    dx = "%rdx"; -  } else { -    ax = "%eax"; -    di = "%edi"; -    dx = "%edx"; -  } - -  switch (node->kind) { -  case ND_ADD: -    println("  add %s, %s", di, ax); -    return; -  case ND_SUB: -    println("  sub %s, %s", di, ax); -    return; -  case ND_MUL: -    println("  imul %s, %s", di, ax); -    return; -  case ND_DIV: -  case ND_MOD: -    if (node->ty->is_unsigned) { -      println("  mov $0, %s", dx); -      println("  div %s", di); -    } else { -      if (node->lhs->ty->size == 8) -        println("  cqo"); -      else -        println("  cdq"); -      println("  idiv %s", di); -    } - -    if (node->kind == ND_MOD) -      println("  mov %%rdx, %%rax"); -    return; -  case ND_BITAND: -    println("  and %s, %s", di, ax); -    return; -  case ND_BITOR: -    println("  or %s, %s", di, ax); -    return; -  case ND_BITXOR: -    println("  xor %s, %s", di, ax); -    return; -  case ND_EQ: -  case ND_NE: -  case ND_LT: -  case ND_LE: -    println("  cmp %s, %s", di, ax); - -    if (node->kind == ND_EQ) { -      println("  sete %%al"); -    } else if (node->kind == ND_NE) { -      println("  setne %%al"); -    } else if (node->kind == ND_LT) { -      if (node->lhs->ty->is_unsigned) -        println("  setb %%al"); -      else -        println("  setl %%al"); -    } else if (node->kind == ND_LE) { -      if (node->lhs->ty->is_unsigned) -        println("  setbe %%al"); -      else -        println("  setle %%al"); -    } - -    println("  movzb %%al, %%rax"); -    return; -  case ND_SHL: -    println("  mov %%rdi, %%rcx"); -    println("  shl %%cl, %s", ax); -    return; -  case ND_SHR: -    println("  mov %%rdi, %%rcx"); -    if (node->lhs->ty->is_unsigned) -      println("  shr %%cl, %s", ax); -    else -      println("  sar %%cl, %s", ax); -    return; -  } - -  error_tok(node->tok, "invalid expression"); -} - -static void gen_stmt(Node *node) { -  println("  .loc %d %d", node->tok->file->file_no, node->tok->line_no); - -  switch (node->kind) { -  case ND_IF: { -    int c = count(); -    gen_expr(node->cond); -    cmp_zero(node->cond->ty); -    println("  je  .L.else.%d", c); -    gen_stmt(node->then); -    println("  jmp .L.end.%d", c); -    println(".L.else.%d:", c); -    if (node->els) -      gen_stmt(node->els); -    println(".L.end.%d:", c); -    return; -  } -  case ND_FOR: { -    int c = count(); -    if (node->init) -      gen_stmt(node->init); -    println(".L.begin.%d:", c); -    if (node->cond) { -      gen_expr(node->cond); -      cmp_zero(node->cond->ty); -      println("  je %s", node->brk_label); -    } -    gen_stmt(node->then); -    println("%s:", node->cont_label); -    if (node->inc) -      gen_expr(node->inc); -    println("  jmp .L.begin.%d", c); -    println("%s:", node->brk_label); -    return; -  } -  case ND_DO: { -    int c = count(); -    println(".L.begin.%d:", c); -    gen_stmt(node->then); -    println("%s:", node->cont_label); -    gen_expr(node->cond); -    cmp_zero(node->cond->ty); -    println("  jne .L.begin.%d", c); -    println("%s:", node->brk_label); -    return; -  } -  case ND_SWITCH: -    gen_expr(node->cond); - -    for (Node *n = node->case_next; n; n = n->case_next) { -      char *ax = (node->cond->ty->size == 8) ? "%rax" : "%eax"; -      char *di = (node->cond->ty->size == 8) ? "%rdi" : "%edi"; - -      if (n->begin == n->end) { -        println("  cmp $%ld, %s", n->begin, ax); -        println("  je %s", n->label); -        continue; -      } - -      // [GNU] Case ranges -      println("  mov %s, %s", ax, di); -      println("  sub $%ld, %s", n->begin, di); -      println("  cmp $%ld, %s", n->end - n->begin, di); -      println("  jbe %s", n->label); -    } - -    if (node->default_case) -      println("  jmp %s", node->default_case->label); - -    println("  jmp %s", node->brk_label); -    gen_stmt(node->then); -    println("%s:", node->brk_label); -    return; -  case ND_CASE: -    println("%s:", node->label); -    gen_stmt(node->lhs); -    return; -  case ND_BLOCK: -    for (Node *n = node->body; n; n = n->next) -      gen_stmt(n); -    return; -  case ND_GOTO: -    println("  jmp %s", node->unique_label); -    return; -  case ND_GOTO_EXPR: -    gen_expr(node->lhs); -    println("  jmp *%%rax"); -    return; -  case ND_LABEL: -    println("%s:", node->unique_label); -    gen_stmt(node->lhs); -    return; -  case ND_RETURN: -    if (node->lhs) { -      gen_expr(node->lhs); -      Type *ty = node->lhs->ty; - -      switch (ty->kind) { -      case TY_STRUCT: -      case TY_UNION: -        if (ty->size <= 16) -          copy_struct_reg(); -        else -          copy_struct_mem(); -        break; -      } -    } - -    println("  jmp .L.return.%s", current_fn->name); -    return; -  case ND_EXPR_STMT: -    gen_expr(node->lhs); -    return; -  case ND_ASM: -    println("  %s", node->asm_str); -    return; -  } - -  error_tok(node->tok, "invalid statement"); -} - -// Assign offsets to local variables. -static void assign_lvar_offsets(Obj *prog) { -  for (Obj *fn = prog; fn; fn = fn->next) { -    if (!fn->is_function) -      continue; - -    // If a function has many parameters, some parameters are -    // inevitably passed by stack rather than by register. -    // The first passed-by-stack parameter resides at RBP+16. -    int top = 16; -    int bottom = 0; - -    int gp = 0, fp = 0; - -    // Assign offsets to pass-by-stack parameters. -    for (Obj *var = fn->params; var; var = var->next) { -      Type *ty = var->ty; - -      switch (ty->kind) { -      case TY_STRUCT: -      case TY_UNION: -        if (ty->size <= 16) { -          bool fp1 = has_flonum(ty, 0, 8, 0); -          bool fp2 = has_flonum(ty, 8, 16, 8); -          if (fp + fp1 + fp2 < FP_MAX && gp + !fp1 + !fp2 < GP_MAX) { -            fp = fp + fp1 + fp2; -            gp = gp + !fp1 + !fp2; -            continue; -          } -        } -        break; -      case TY_FLOAT: -      case TY_DOUBLE: -        if (fp++ < FP_MAX) -          continue; -        break; -      case TY_LDOUBLE: -        break; -      default: -        if (gp++ < GP_MAX) -          continue; -      } - -      top = align_to(top, 8); -      var->offset = top; -      top += var->ty->size; -    } - -    // Assign offsets to pass-by-register parameters and local variables. -    for (Obj *var = fn->locals; var; var = var->next) { -      if (var->offset) -        continue; - -      // AMD64 System V ABI has a special alignment rule for an array of -      // length at least 16 bytes. We need to align such array to at least -      // 16-byte boundaries. See p.14 of -      // https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-draft.pdf. -      int align = (var->ty->kind == TY_ARRAY && var->ty->size >= 16) -        ? MAX(16, var->align) : var->align; - -      bottom += var->ty->size; -      bottom = align_to(bottom, align); -      var->offset = -bottom; -    } - -    fn->stack_size = align_to(bottom, 16); -  } -} - -static void emit_data(Obj *prog) { -  for (Obj *var = prog; var; var = var->next) { -    if (var->is_function || !var->is_definition) -      continue; - -    if (var->is_static) -      println("  .local %s", var->name); -    else -      println("  .globl %s", var->name); - -    int align = (var->ty->kind == TY_ARRAY && var->ty->size >= 16) -      ? MAX(16, var->align) : var->align; - -    // Common symbol -    if (opt_fcommon && var->is_tentative) { -      println("  .comm %s, %d, %d", var->name, var->ty->size, align); -      continue; -    } - -    // .data or .tdata -    if (var->init_data) { -      if (var->is_tls) -        println("  .section .tdata,\"awT\",@progbits"); -      else -        println("  .data"); - -      println("  .type %s, @object", var->name); -      println("  .size %s, %d", var->name, var->ty->size); -      println("  .align %d", align); -      println("%s:", var->name); - -      Relocation *rel = var->rel; -      int pos = 0; -      while (pos < var->ty->size) { -        if (rel && rel->offset == pos) { -          println("  .quad %s%+ld", *rel->label, rel->addend); -          rel = rel->next; -          pos += 8; -        } else { -          println("  .byte %d", var->init_data[pos++]); -        } -      } -      continue; -    } - -    // .bss or .tbss -    if (var->is_tls) -      println("  .section .tbss,\"awT\",@nobits"); -    else -      println("  .bss"); - -    println("  .align %d", align); -    println("%s:", var->name); -    println("  .zero %d", var->ty->size); -  } -} - -static void store_fp(int r, int offset, int sz) { -  switch (sz) { -  case 4: -    println("  movss %%xmm%d, %d(%%rbp)", r, offset); -    return; -  case 8: -    println("  movsd %%xmm%d, %d(%%rbp)", r, offset); -    return; -  } -  unreachable(); -} - -static void store_gp(int r, int offset, int sz) { -  switch (sz) { -  case 1: -    println("  mov %s, %d(%%rbp)", argreg8[r], offset); -    return; -  case 2: -    println("  mov %s, %d(%%rbp)", argreg16[r], offset); -    return; -  case 4: -    println("  mov %s, %d(%%rbp)", argreg32[r], offset); -    return; -  case 8: -    println("  mov %s, %d(%%rbp)", argreg64[r], offset); -    return; -  default: -    for (int i = 0; i < sz; i++) { -      println("  mov %s, %d(%%rbp)", argreg8[r], offset + i); -      println("  shr $8, %s", argreg64[r]); -    } -    return; -  } -} - -static void emit_text(Obj *prog) { -  for (Obj *fn = prog; fn; fn = fn->next) { -    if (!fn->is_function || !fn->is_definition) -      continue; - -    // No code is emitted for "static inline" functions -    // if no one is referencing them. -    if (!fn->is_live) -      continue; - -    if (fn->is_static) -      println("  .local %s", fn->name); -    else -      println("  .globl %s", fn->name); - -    println("  .text"); -    println("  .type %s, @function", fn->name); -    println("%s:", fn->name); -    current_fn = fn; - -    // Prologue -    println("  push %%rbp"); -    println("  mov %%rsp, %%rbp"); -    println("  sub $%d, %%rsp", fn->stack_size); -    println("  mov %%rsp, %d(%%rbp)", fn->alloca_bottom->offset); - -    // Save arg registers if function is variadic -    if (fn->va_area) { -      int gp = 0, fp = 0; -      for (Obj *var = fn->params; var; var = var->next) { -        if (is_flonum(var->ty)) -          fp++; -        else -          gp++; -      } - -      int off = fn->va_area->offset; - -      // va_elem -      println("  movl $%d, %d(%%rbp)", gp * 8, off);          // gp_offset -      println("  movl $%d, %d(%%rbp)", fp * 8 + 48, off + 4); // fp_offset -      println("  movq %%rbp, %d(%%rbp)", off + 8);            // overflow_arg_area -      println("  addq $16, %d(%%rbp)", off + 8); -      println("  movq %%rbp, %d(%%rbp)", off + 16);           // reg_save_area -      println("  addq $%d, %d(%%rbp)", off + 24, off + 16); - -      // __reg_save_area__ -      println("  movq %%rdi, %d(%%rbp)", off + 24); -      println("  movq %%rsi, %d(%%rbp)", off + 32); -      println("  movq %%rdx, %d(%%rbp)", off + 40); -      println("  movq %%rcx, %d(%%rbp)", off + 48); -      println("  movq %%r8, %d(%%rbp)", off + 56); -      println("  movq %%r9, %d(%%rbp)", off + 64); -      println("  movsd %%xmm0, %d(%%rbp)", off + 72); -      println("  movsd %%xmm1, %d(%%rbp)", off + 80); -      println("  movsd %%xmm2, %d(%%rbp)", off + 88); -      println("  movsd %%xmm3, %d(%%rbp)", off + 96); -      println("  movsd %%xmm4, %d(%%rbp)", off + 104); -      println("  movsd %%xmm5, %d(%%rbp)", off + 112); -      println("  movsd %%xmm6, %d(%%rbp)", off + 120); -      println("  movsd %%xmm7, %d(%%rbp)", off + 128); -    } - -    // Save passed-by-register arguments to the stack -    int gp = 0, fp = 0; -    for (Obj *var = fn->params; var; var = var->next) { -      if (var->offset > 0) -        continue; - -      Type *ty = var->ty; - -      switch (ty->kind) { -      case TY_STRUCT: -      case TY_UNION: -        assert(ty->size <= 16); -        if (has_flonum(ty, 0, 8, 0)) -          store_fp(fp++, var->offset, MIN(8, ty->size)); -        else -          store_gp(gp++, var->offset, MIN(8, ty->size)); - -        if (ty->size > 8) { -          if (has_flonum(ty, 8, 16, 0)) -            store_fp(fp++, var->offset + 8, ty->size - 8); -          else -            store_gp(gp++, var->offset + 8, ty->size - 8); -        } -        break; -      case TY_FLOAT: -      case TY_DOUBLE: -        store_fp(fp++, var->offset, ty->size); -        break; -      default: -        store_gp(gp++, var->offset, ty->size); -      } -    } - -    // Emit code -    gen_stmt(fn->body); -    assert(depth == 0); - -    // [https://www.sigbus.info/n1570#5.1.2.2.3p1] The C spec defines -    // a special rule for the main function. Reaching the end of the -    // main function is equivalent to returning 0, even though the -    // behavior is undefined for the other functions. -    if (strcmp(fn->name, "main") == 0) -      println("  mov $0, %%rax"); - -    // Epilogue -    println(".L.return.%s:", fn->name); -    println("  mov %%rbp, %%rsp"); -    println("  pop %%rbp"); -    println("  ret"); -  } -} - -void codegen(Obj *prog, FILE *out) { -  output_file = out; - -  File **files = get_input_files(); -  for (int i = 0; files[i]; i++) -    println("  .file %d \"%s\"", files[i]->file_no, files[i]->name); - -  assign_lvar_offsets(prog); -  emit_data(prog); -  emit_text(prog); -} diff --git a/src/3p/chibicc/main.c b/src/3p/chibicc/main.c deleted file mode 100644 index ffaabf4..0000000 --- a/src/3p/chibicc/main.c +++ /dev/null @@ -1,791 +0,0 @@ -#include "chibicc.h" - -typedef enum { -  FILE_NONE, FILE_C, FILE_ASM, FILE_OBJ, FILE_AR, FILE_DSO, -} FileType; - -StringArray include_paths; -bool opt_fcommon = true; -bool opt_fpic; - -static FileType opt_x; -static StringArray opt_include; -static bool opt_E; -static bool opt_M; -static bool opt_MD; -static bool opt_MMD; -static bool opt_MP; -static bool opt_S; -static bool opt_c; -static bool opt_cc1; -static bool opt_hash_hash_hash; -static bool opt_static; -static bool opt_shared; -static char *opt_MF; -static char *opt_MT; -static char *opt_o; - -static StringArray ld_extra_args; -static StringArray std_include_paths; - -char *base_file; -static char *output_file; - -static StringArray input_paths; -static StringArray tmpfiles; - -static void usage(int status) { -  fprintf(stderr, "chibicc [ -o <path> ] <file>\n"); -  exit(status); -} - -static bool take_arg(char *arg) { -  char *x[] = { -    "-o", "-I", "-idirafter", "-include", "-x", "-MF", "-MT", "-Xlinker", -  }; - -  for (int i = 0; i < sizeof(x) / sizeof(*x); i++) -    if (!strcmp(arg, x[i])) -      return true; -  return false; -} - -static void add_default_include_paths(char *argv0) { -  // We expect that chibicc-specific include files are installed -  // to ./include relative to argv[0]. -  strarray_push(&include_paths, format("%s/include", dirname(strdup(argv0)))); - -  // Add standard include paths. -  strarray_push(&include_paths, "/usr/local/include"); -  strarray_push(&include_paths, "/usr/include/x86_64-linux-gnu"); -  strarray_push(&include_paths, "/usr/include"); - -  // Keep a copy of the standard include paths for -MMD option. -  for (int i = 0; i < include_paths.len; i++) -    strarray_push(&std_include_paths, include_paths.data[i]); -} - -static void define(char *str) { -  char *eq = strchr(str, '='); -  if (eq) -    define_macro(strndup(str, eq - str), eq + 1); -  else -    define_macro(str, "1"); -} - -static FileType parse_opt_x(char *s) { -  if (!strcmp(s, "c")) -    return FILE_C; -  if (!strcmp(s, "assembler")) -    return FILE_ASM; -  if (!strcmp(s, "none")) -    return FILE_NONE; -  error("<command line>: unknown argument for -x: %s", s); -} - -static char *quote_makefile(char *s) { -  char *buf = calloc(1, strlen(s) * 2 + 1); - -  for (int i = 0, j = 0; s[i]; i++) { -    switch (s[i]) { -    case '$': -      buf[j++] = '$'; -      buf[j++] = '$'; -      break; -    case '#': -      buf[j++] = '\\'; -      buf[j++] = '#'; -      break; -    case ' ': -    case '\t': -      for (int k = i - 1; k >= 0 && s[k] == '\\'; k--) -        buf[j++] = '\\'; -      buf[j++] = '\\'; -      buf[j++] = s[i]; -      break; -    default: -      buf[j++] = s[i]; -      break; -    } -  } -  return buf; -} - -static void parse_args(int argc, char **argv) { -  // Make sure that all command line options that take an argument -  // have an argument. -  for (int i = 1; i < argc; i++) -    if (take_arg(argv[i])) -      if (!argv[++i]) -        usage(1); - -  StringArray idirafter = {}; - -  for (int i = 1; i < argc; i++) { -    if (!strcmp(argv[i], "-###")) { -      opt_hash_hash_hash = true; -      continue; -    } - -    if (!strcmp(argv[i], "-cc1")) { -      opt_cc1 = true; -      continue; -    } - -    if (!strcmp(argv[i], "--help")) -      usage(0); - -    if (!strcmp(argv[i], "-o")) { -      opt_o = argv[++i]; -      continue; -    } - -    if (!strncmp(argv[i], "-o", 2)) { -      opt_o = argv[i] + 2; -      continue; -    } - -    if (!strcmp(argv[i], "-S")) { -      opt_S = true; -      continue; -    } - -    if (!strcmp(argv[i], "-fcommon")) { -      opt_fcommon = true; -      continue; -    } - -    if (!strcmp(argv[i], "-fno-common")) { -      opt_fcommon = false; -      continue; -    } - -    if (!strcmp(argv[i], "-c")) { -      opt_c = true; -      continue; -    } - -    if (!strcmp(argv[i], "-E")) { -      opt_E = true; -      continue; -    } - -    if (!strncmp(argv[i], "-I", 2)) { -      strarray_push(&include_paths, argv[i] + 2); -      continue; -    } - -    if (!strcmp(argv[i], "-D")) { -      define(argv[++i]); -      continue; -    } - -    if (!strncmp(argv[i], "-D", 2)) { -      define(argv[i] + 2); -      continue; -    } - -    if (!strcmp(argv[i], "-U")) { -      undef_macro(argv[++i]); -      continue; -    } - -    if (!strncmp(argv[i], "-U", 2)) { -      undef_macro(argv[i] + 2); -      continue; -    } - -    if (!strcmp(argv[i], "-include")) { -      strarray_push(&opt_include, argv[++i]); -      continue; -    } - -    if (!strcmp(argv[i], "-x")) { -      opt_x = parse_opt_x(argv[++i]); -      continue; -    } - -    if (!strncmp(argv[i], "-x", 2)) { -      opt_x = parse_opt_x(argv[i] + 2); -      continue; -    } - -    if (!strncmp(argv[i], "-l", 2) || !strncmp(argv[i], "-Wl,", 4)) { -      strarray_push(&input_paths, argv[i]); -      continue; -    } - -    if (!strcmp(argv[i], "-Xlinker")) { -      strarray_push(&ld_extra_args, argv[++i]); -      continue; -    } - -    if (!strcmp(argv[i], "-s")) { -      strarray_push(&ld_extra_args, "-s"); -      continue; -    } - -    if (!strcmp(argv[i], "-M")) { -      opt_M = true; -      continue; -    } - -    if (!strcmp(argv[i], "-MF")) { -      opt_MF = argv[++i]; -      continue; -    } - -    if (!strcmp(argv[i], "-MP")) { -      opt_MP = true; -      continue; -    } - -    if (!strcmp(argv[i], "-MT")) { -      if (opt_MT == NULL) -        opt_MT = argv[++i]; -      else -        opt_MT = format("%s %s", opt_MT, argv[++i]); -      continue; -    } - -    if (!strcmp(argv[i], "-MD")) { -      opt_MD = true; -      continue; -    } - -    if (!strcmp(argv[i], "-MQ")) { -      if (opt_MT == NULL) -        opt_MT = quote_makefile(argv[++i]); -      else -        opt_MT = format("%s %s", opt_MT, quote_makefile(argv[++i])); -      continue; -    } - -    if (!strcmp(argv[i], "-MMD")) { -      opt_MD = opt_MMD = true; -      continue; -    } - -    if (!strcmp(argv[i], "-fpic") || !strcmp(argv[i], "-fPIC")) { -      opt_fpic = true; -      continue; -    } - -    if (!strcmp(argv[i], "-cc1-input")) { -      base_file = argv[++i]; -      continue; -    } - -    if (!strcmp(argv[i], "-cc1-output")) { -      output_file = argv[++i]; -      continue; -    } - -    if (!strcmp(argv[i], "-idirafter")) { -      strarray_push(&idirafter, argv[i++]); -      continue; -    } - -    if (!strcmp(argv[i], "-static")) { -      opt_static = true; -      strarray_push(&ld_extra_args, "-static"); -      continue; -    } - -    if (!strcmp(argv[i], "-shared")) { -      opt_shared = true; -      strarray_push(&ld_extra_args, "-shared"); -      continue; -    } - -    if (!strcmp(argv[i], "-L")) { -      strarray_push(&ld_extra_args, "-L"); -      strarray_push(&ld_extra_args, argv[++i]); -      continue; -    } - -    if (!strncmp(argv[i], "-L", 2)) { -      strarray_push(&ld_extra_args, "-L"); -      strarray_push(&ld_extra_args, argv[i] + 2); -      continue; -    } - -    if (!strcmp(argv[i], "-hashmap-test")) { -      hashmap_test(); -      exit(0); -    } - -    // These options are ignored for now. -    if (!strncmp(argv[i], "-O", 2) || -        !strncmp(argv[i], "-W", 2) || -        !strncmp(argv[i], "-g", 2) || -        !strncmp(argv[i], "-std=", 5) || -        !strcmp(argv[i], "-ffreestanding") || -        !strcmp(argv[i], "-fno-builtin") || -        !strcmp(argv[i], "-fno-omit-frame-pointer") || -        !strcmp(argv[i], "-fno-stack-protector") || -        !strcmp(argv[i], "-fno-strict-aliasing") || -        !strcmp(argv[i], "-m64") || -        !strcmp(argv[i], "-mno-red-zone") || -        !strcmp(argv[i], "-w")) -      continue; - -    if (argv[i][0] == '-' && argv[i][1] != '\0') -      error("unknown argument: %s", argv[i]); - -    strarray_push(&input_paths, argv[i]); -  } - -  for (int i = 0; i < idirafter.len; i++) -    strarray_push(&include_paths, idirafter.data[i]); - -  if (input_paths.len == 0) -    error("no input files"); - -  // -E implies that the input is the C macro language. -  if (opt_E) -    opt_x = FILE_C; -} - -static FILE *open_file(char *path) { -  if (!path || strcmp(path, "-") == 0) -    return stdout; - -  FILE *out = fopen(path, "w"); -  if (!out) -    error("cannot open output file: %s: %s", path, strerror(errno)); -  return out; -} - -static bool endswith(char *p, char *q) { -  int len1 = strlen(p); -  int len2 = strlen(q); -  return (len1 >= len2) && !strcmp(p + len1 - len2, q); -} - -// Replace file extension -static char *replace_extn(char *tmpl, char *extn) { -  char *filename = basename(strdup(tmpl)); -  char *dot = strrchr(filename, '.'); -  if (dot) -    *dot = '\0'; -  return format("%s%s", filename, extn); -} - -static void cleanup(void) { -  for (int i = 0; i < tmpfiles.len; i++) -    unlink(tmpfiles.data[i]); -} - -static char *create_tmpfile(void) { -  char *path = strdup("/tmp/chibicc-XXXXXX"); -  int fd = mkstemp(path); -  if (fd == -1) -    error("mkstemp failed: %s", strerror(errno)); -  close(fd); - -  strarray_push(&tmpfiles, path); -  return path; -} - -static void run_subprocess(char **argv) { -  // If -### is given, dump the subprocess's command line. -  if (opt_hash_hash_hash) { -    fprintf(stderr, "%s", argv[0]); -    for (int i = 1; argv[i]; i++) -      fprintf(stderr, " %s", argv[i]); -    fprintf(stderr, "\n"); -  } - -  if (fork() == 0) { -    // Child process. Run a new command. -    execvp(argv[0], argv); -    fprintf(stderr, "exec failed: %s: %s\n", argv[0], strerror(errno)); -    _exit(1); -  } - -  // Wait for the child process to finish. -  int status; -  while (wait(&status) > 0); -  if (status != 0) -    exit(1); -} - -static void run_cc1(int argc, char **argv, char *input, char *output) { -  char **args = calloc(argc + 10, sizeof(char *)); -  memcpy(args, argv, argc * sizeof(char *)); -  args[argc++] = "-cc1"; - -  if (input) { -    args[argc++] = "-cc1-input"; -    args[argc++] = input; -  } - -  if (output) { -    args[argc++] = "-cc1-output"; -    args[argc++] = output; -  } - -  run_subprocess(args); -} - -// Print tokens to stdout. Used for -E. -static void print_tokens(Token *tok) { -  FILE *out = open_file(opt_o ? opt_o : "-"); - -  int line = 1; -  for (; tok->kind != TK_EOF; tok = tok->next) { -    if (line > 1 && tok->at_bol) -      fprintf(out, "\n"); -    if (tok->has_space && !tok->at_bol) -      fprintf(out, " "); -    fprintf(out, "%.*s", tok->len, tok->loc); -    line++; -  } -  fprintf(out, "\n"); -} - -static bool in_std_include_path(char *path) { -  for (int i = 0; i < std_include_paths.len; i++) { -    char *dir = std_include_paths.data[i]; -    int len = strlen(dir); -    if (strncmp(dir, path, len) == 0 && path[len] == '/') -      return true; -  } -  return false; -} - -// If -M options is given, the compiler write a list of input files to -// stdout in a format that "make" command can read. This feature is -// used to automate file dependency management. -static void print_dependencies(void) { -  char *path; -  if (opt_MF) -    path = opt_MF; -  else if (opt_MD) -    path = replace_extn(opt_o ? opt_o : base_file, ".d"); -  else if (opt_o) -    path = opt_o; -  else -    path = "-"; - -  FILE *out = open_file(path); -  if (opt_MT) -    fprintf(out, "%s:", opt_MT); -  else -    fprintf(out, "%s:", quote_makefile(replace_extn(base_file, ".o"))); - -  File **files = get_input_files(); - -  for (int i = 0; files[i]; i++) { -    if (opt_MMD && in_std_include_path(files[i]->name)) -      continue; -    fprintf(out, " \\\n  %s", files[i]->name); -  } - -  fprintf(out, "\n\n"); - -  if (opt_MP) { -    for (int i = 1; files[i]; i++) { -      if (opt_MMD && in_std_include_path(files[i]->name)) -        continue; -      fprintf(out, "%s:\n\n", quote_makefile(files[i]->name)); -    } -  } -} - -static Token *must_tokenize_file(char *path) { -  Token *tok = tokenize_file(path); -  if (!tok) -    error("%s: %s", path, strerror(errno)); -  return tok; -} - -static Token *append_tokens(Token *tok1, Token *tok2) { -  if (!tok1 || tok1->kind == TK_EOF) -    return tok2; - -  Token *t = tok1; -  while (t->next->kind != TK_EOF) -    t = t->next; -  t->next = tok2; -  return tok1; -} - -static void cc1(void) { -  Token *tok = NULL; - -  // Process -include option -  for (int i = 0; i < opt_include.len; i++) { -    char *incl = opt_include.data[i]; - -    char *path; -    if (file_exists(incl)) { -      path = incl; -    } else { -      path = search_include_paths(incl); -      if (!path) -        error("-include: %s: %s", incl, strerror(errno)); -    } - -    Token *tok2 = must_tokenize_file(path); -    tok = append_tokens(tok, tok2); -  } - -  // Tokenize and parse. -  Token *tok2 = must_tokenize_file(base_file); -  tok = append_tokens(tok, tok2); -  tok = preprocess(tok); - -  // If -M or -MD are given, print file dependencies. -  if (opt_M || opt_MD) { -    print_dependencies(); -    if (opt_M) -      return; -  } - -  // If -E is given, print out preprocessed C code as a result. -  if (opt_E) { -    print_tokens(tok); -    return; -  } - -  Obj *prog = parse(tok); - -  // Open a temporary output buffer. -  char *buf; -  size_t buflen; -  FILE *output_buf = open_memstream(&buf, &buflen); - -  // Traverse the AST to emit assembly. -  codegen(prog, output_buf); -  fclose(output_buf); - -  // Write the asembly text to a file. -  FILE *out = open_file(output_file); -  fwrite(buf, buflen, 1, out); -  fclose(out); -} - -static void assemble(char *input, char *output) { -  char *cmd[] = {"as", "-c", input, "-o", output, NULL}; -  run_subprocess(cmd); -} - -static char *find_file(char *pattern) { -  char *path = NULL; -  glob_t buf = {}; -  glob(pattern, 0, NULL, &buf); -  if (buf.gl_pathc > 0) -    path = strdup(buf.gl_pathv[buf.gl_pathc - 1]); -  globfree(&buf); -  return path; -} - -// Returns true if a given file exists. -bool file_exists(char *path) { -  struct stat st; -  return !stat(path, &st); -} - -static char *find_libpath(void) { -  if (file_exists("/usr/lib/x86_64-linux-gnu/crti.o")) -    return "/usr/lib/x86_64-linux-gnu"; -  if (file_exists("/usr/lib64/crti.o")) -    return "/usr/lib64"; -  error("library path is not found"); -} - -static char *find_gcc_libpath(void) { -  char *paths[] = { -    "/usr/lib/gcc/x86_64-linux-gnu/*/crtbegin.o", -    "/usr/lib/gcc/x86_64-pc-linux-gnu/*/crtbegin.o", // For Gentoo -    "/usr/lib/gcc/x86_64-redhat-linux/*/crtbegin.o", // For Fedora -  }; - -  for (int i = 0; i < sizeof(paths) / sizeof(*paths); i++) { -    char *path = find_file(paths[i]); -    if (path) -      return dirname(path); -  } - -  error("gcc library path is not found"); -} - -static void run_linker(StringArray *inputs, char *output) { -  StringArray arr = {}; - -  strarray_push(&arr, "ld"); -  strarray_push(&arr, "-o"); -  strarray_push(&arr, output); -  strarray_push(&arr, "-m"); -  strarray_push(&arr, "elf_x86_64"); - -  char *libpath = find_libpath(); -  char *gcc_libpath = find_gcc_libpath(); - -  if (opt_shared) { -    strarray_push(&arr, format("%s/crti.o", libpath)); -    strarray_push(&arr, format("%s/crtbeginS.o", gcc_libpath)); -  } else { -    strarray_push(&arr, format("%s/crt1.o", libpath)); -    strarray_push(&arr, format("%s/crti.o", libpath)); -    strarray_push(&arr, format("%s/crtbegin.o", gcc_libpath)); -  } - -  strarray_push(&arr, format("-L%s", gcc_libpath)); -  strarray_push(&arr, "-L/usr/lib/x86_64-linux-gnu"); -  strarray_push(&arr, "-L/usr/lib64"); -  strarray_push(&arr, "-L/lib64"); -  strarray_push(&arr, "-L/usr/lib/x86_64-linux-gnu"); -  strarray_push(&arr, "-L/usr/lib/x86_64-pc-linux-gnu"); -  strarray_push(&arr, "-L/usr/lib/x86_64-redhat-linux"); -  strarray_push(&arr, "-L/usr/lib"); -  strarray_push(&arr, "-L/lib"); - -  if (!opt_static) { -    strarray_push(&arr, "-dynamic-linker"); -    strarray_push(&arr, "/lib64/ld-linux-x86-64.so.2"); -  } - -  for (int i = 0; i < ld_extra_args.len; i++) -    strarray_push(&arr, ld_extra_args.data[i]); - -  for (int i = 0; i < inputs->len; i++) -    strarray_push(&arr, inputs->data[i]); - -  if (opt_static) { -    strarray_push(&arr, "--start-group"); -    strarray_push(&arr, "-lgcc"); -    strarray_push(&arr, "-lgcc_eh"); -    strarray_push(&arr, "-lc"); -    strarray_push(&arr, "--end-group"); -  } else { -    strarray_push(&arr, "-lc"); -    strarray_push(&arr, "-lgcc"); -    strarray_push(&arr, "--as-needed"); -    strarray_push(&arr, "-lgcc_s"); -    strarray_push(&arr, "--no-as-needed"); -  } - -  if (opt_shared) -    strarray_push(&arr, format("%s/crtendS.o", gcc_libpath)); -  else -    strarray_push(&arr, format("%s/crtend.o", gcc_libpath)); - -  strarray_push(&arr, format("%s/crtn.o", libpath)); -  strarray_push(&arr, NULL); - -  run_subprocess(arr.data); -} - -static FileType get_file_type(char *filename) { -  if (opt_x != FILE_NONE) -    return opt_x; - -  if (endswith(filename, ".a")) -    return FILE_AR; -  if (endswith(filename, ".so")) -    return FILE_DSO; -  if (endswith(filename, ".o")) -    return FILE_OBJ; -  if (endswith(filename, ".c")) -    return FILE_C; -  if (endswith(filename, ".s")) -    return FILE_ASM; - -  error("<command line>: unknown file extension: %s", filename); -} - -int main(int argc, char **argv) { -  atexit(cleanup); -  init_macros(); -  parse_args(argc, argv); - -  if (opt_cc1) { -    add_default_include_paths(argv[0]); -    cc1(); -    return 0; -  } - -  if (input_paths.len > 1 && opt_o && (opt_c || opt_S | opt_E)) -    error("cannot specify '-o' with '-c,' '-S' or '-E' with multiple files"); - -  StringArray ld_args = {}; - -  for (int i = 0; i < input_paths.len; i++) { -    char *input = input_paths.data[i]; - -    if (!strncmp(input, "-l", 2)) { -      strarray_push(&ld_args, input); -      continue; -    } - -    if (!strncmp(input, "-Wl,", 4)) { -      char *s = strdup(input + 4); -      char *arg = strtok(s, ","); -      while (arg) { -        strarray_push(&ld_args, arg); -        arg = strtok(NULL, ","); -      } -      continue; -    } - -    char *output; -    if (opt_o) -      output = opt_o; -    else if (opt_S) -      output = replace_extn(input, ".s"); -    else -      output = replace_extn(input, ".o"); - -    FileType type = get_file_type(input); - -    // Handle .o or .a -    if (type == FILE_OBJ || type == FILE_AR || type == FILE_DSO) { -      strarray_push(&ld_args, input); -      continue; -    } - -    // Handle .s -    if (type == FILE_ASM) { -      if (!opt_S) -        assemble(input, output); -      continue; -    } - -    assert(type == FILE_C); - -    // Just preprocess -    if (opt_E || opt_M) { -      run_cc1(argc, argv, input, NULL); -      continue; -    } - -    // Compile -    if (opt_S) { -      run_cc1(argc, argv, input, output); -      continue; -    } - -    // Compile and assemble -    if (opt_c) { -      char *tmp = create_tmpfile(); -      run_cc1(argc, argv, input, tmp); -      assemble(tmp, output); -      continue; -    } - -    // Compile, assemble and link -    char *tmp1 = create_tmpfile(); -    char *tmp2 = create_tmpfile(); -    run_cc1(argc, argv, input, tmp1); -    assemble(tmp1, tmp2); -    strarray_push(&ld_args, tmp2); -    continue; -  } - -  if (ld_args.len > 0) -    run_linker(&ld_args, opt_o ? opt_o : "a.out"); -  return 0; -} diff --git a/src/3p/chibicc/parse.c b/src/3p/chibicc/parse.c deleted file mode 100644 index 6acaeb8..0000000 --- a/src/3p/chibicc/parse.c +++ /dev/null @@ -1,3368 +0,0 @@ -// This file contains a recursive descent parser for C. -// -// Most functions in this file are named after the symbols they are -// supposed to read from an input token list. For example, stmt() is -// responsible for reading a statement from a token list. The function -// then construct an AST node representing a statement. -// -// Each function conceptually returns two values, an AST node and -// remaining part of the input tokens. Since C doesn't support -// multiple return values, the remaining tokens are returned to the -// caller via a pointer argument. -// -// Input tokens are represented by a linked list. Unlike many recursive -// descent parsers, we don't have the notion of the "input token stream". -// Most parsing functions don't change the global state of the parser. -// So it is very easy to lookahead arbitrary number of tokens in this -// parser. - -#include "chibicc.h" - -// Scope for local variables, global variables, typedefs -// or enum constants -typedef struct { -  Obj *var; -  Type *type_def; -  Type *enum_ty; -  int enum_val; -} VarScope; - -// Represents a block scope. -typedef struct Scope Scope; -struct Scope { -  Scope *next; - -  // C has two block scopes; one is for variables/typedefs and -  // the other is for struct/union/enum tags. -  HashMap vars; -  HashMap tags; -}; - -// Variable attributes such as typedef or extern. -typedef struct { -  bool is_typedef; -  bool is_static; -  bool is_extern; -  bool is_inline; -  bool is_tls; -  int align; -} VarAttr; - -// This struct represents a variable initializer. Since initializers -// can be nested (e.g. `int x[2][2] = {{1, 2}, {3, 4}}`), this struct -// is a tree data structure. -typedef struct Initializer Initializer; -struct Initializer { -  Initializer *next; -  Type *ty; -  Token *tok; -  bool is_flexible; - -  // If it's not an aggregate type and has an initializer, -  // `expr` has an initialization expression. -  Node *expr; - -  // If it's an initializer for an aggregate type (e.g. array or struct), -  // `children` has initializers for its children. -  Initializer **children; - -  // Only one member can be initialized for a union. -  // `mem` is used to clarify which member is initialized. -  Member *mem; -}; - -// For local variable initializer. -typedef struct InitDesg InitDesg; -struct InitDesg { -  InitDesg *next; -  int idx; -  Member *member; -  Obj *var; -}; - -// All local variable instances created during parsing are -// accumulated to this list. -static Obj *locals; - -// Likewise, global variables are accumulated to this list. -static Obj *globals; - -static Scope *scope = &(Scope){}; - -// Points to the function object the parser is currently parsing. -static Obj *current_fn; - -// Lists of all goto statements and labels in the curent function. -static Node *gotos; -static Node *labels; - -// Current "goto" and "continue" jump targets. -static char *brk_label; -static char *cont_label; - -// Points to a node representing a switch if we are parsing -// a switch statement. Otherwise, NULL. -static Node *current_switch; - -static Obj *builtin_alloca; - -static bool is_typename(Token *tok); -static Type *declspec(Token **rest, Token *tok, VarAttr *attr); -static Type *typename(Token **rest, Token *tok); -static Type *enum_specifier(Token **rest, Token *tok); -static Type *typeof_specifier(Token **rest, Token *tok); -static Type *type_suffix(Token **rest, Token *tok, Type *ty); -static Type *declarator(Token **rest, Token *tok, Type *ty); -static Node *declaration(Token **rest, Token *tok, Type *basety, VarAttr *attr); -static void array_initializer2(Token **rest, Token *tok, Initializer *init, int i); -static void struct_initializer2(Token **rest, Token *tok, Initializer *init, Member *mem); -static void initializer2(Token **rest, Token *tok, Initializer *init); -static Initializer *initializer(Token **rest, Token *tok, Type *ty, Type **new_ty); -static Node *lvar_initializer(Token **rest, Token *tok, Obj *var); -static void gvar_initializer(Token **rest, Token *tok, Obj *var); -static Node *compound_stmt(Token **rest, Token *tok); -static Node *stmt(Token **rest, Token *tok); -static Node *expr_stmt(Token **rest, Token *tok); -static Node *expr(Token **rest, Token *tok); -static int64_t eval(Node *node); -static int64_t eval2(Node *node, char ***label); -static int64_t eval_rval(Node *node, char ***label); -static bool is_const_expr(Node *node); -static Node *assign(Token **rest, Token *tok); -static Node *logor(Token **rest, Token *tok); -static double eval_double(Node *node); -static Node *conditional(Token **rest, Token *tok); -static Node *logand(Token **rest, Token *tok); -static Node *bitor(Token **rest, Token *tok); -static Node *bitxor(Token **rest, Token *tok); -static Node *bitand(Token **rest, Token *tok); -static Node *equality(Token **rest, Token *tok); -static Node *relational(Token **rest, Token *tok); -static Node *shift(Token **rest, Token *tok); -static Node *add(Token **rest, Token *tok); -static Node *new_add(Node *lhs, Node *rhs, Token *tok); -static Node *new_sub(Node *lhs, Node *rhs, Token *tok); -static Node *mul(Token **rest, Token *tok); -static Node *cast(Token **rest, Token *tok); -static Member *get_struct_member(Type *ty, Token *tok); -static Type *struct_decl(Token **rest, Token *tok); -static Type *union_decl(Token **rest, Token *tok); -static Node *postfix(Token **rest, Token *tok); -static Node *funcall(Token **rest, Token *tok, Node *node); -static Node *unary(Token **rest, Token *tok); -static Node *primary(Token **rest, Token *tok); -static Token *parse_typedef(Token *tok, Type *basety); -static bool is_function(Token *tok); -static Token *function(Token *tok, Type *basety, VarAttr *attr); -static Token *global_variable(Token *tok, Type *basety, VarAttr *attr); - -static int align_down(int n, int align) { -  return align_to(n - align + 1, align); -} - -static void enter_scope(void) { -  Scope *sc = calloc(1, sizeof(Scope)); -  sc->next = scope; -  scope = sc; -} - -static void leave_scope(void) { -  scope = scope->next; -} - -// Find a variable by name. -static VarScope *find_var(Token *tok) { -  for (Scope *sc = scope; sc; sc = sc->next) { -    VarScope *sc2 = hashmap_get2(&sc->vars, tok->loc, tok->len); -    if (sc2) -      return sc2; -  } -  return NULL; -} - -static Type *find_tag(Token *tok) { -  for (Scope *sc = scope; sc; sc = sc->next) { -    Type *ty = hashmap_get2(&sc->tags, tok->loc, tok->len); -    if (ty) -      return ty; -  } -  return NULL; -} - -static Node *new_node(NodeKind kind, Token *tok) { -  Node *node = calloc(1, sizeof(Node)); -  node->kind = kind; -  node->tok = tok; -  return node; -} - -static Node *new_binary(NodeKind kind, Node *lhs, Node *rhs, Token *tok) { -  Node *node = new_node(kind, tok); -  node->lhs = lhs; -  node->rhs = rhs; -  return node; -} - -static Node *new_unary(NodeKind kind, Node *expr, Token *tok) { -  Node *node = new_node(kind, tok); -  node->lhs = expr; -  return node; -} - -static Node *new_num(int64_t val, Token *tok) { -  Node *node = new_node(ND_NUM, tok); -  node->val = val; -  return node; -} - -static Node *new_long(int64_t val, Token *tok) { -  Node *node = new_node(ND_NUM, tok); -  node->val = val; -  node->ty = ty_long; -  return node; -} - -static Node *new_ulong(long val, Token *tok) { -  Node *node = new_node(ND_NUM, tok); -  node->val = val; -  node->ty = ty_ulong; -  return node; -} - -static Node *new_var_node(Obj *var, Token *tok) { -  Node *node = new_node(ND_VAR, tok); -  node->var = var; -  return node; -} - -static Node *new_vla_ptr(Obj *var, Token *tok) { -  Node *node = new_node(ND_VLA_PTR, tok); -  node->var = var; -  return node; -} - -Node *new_cast(Node *expr, Type *ty) { -  add_type(expr); - -  Node *node = calloc(1, sizeof(Node)); -  node->kind = ND_CAST; -  node->tok = expr->tok; -  node->lhs = expr; -  node->ty = copy_type(ty); -  return node; -} - -static VarScope *push_scope(char *name) { -  VarScope *sc = calloc(1, sizeof(VarScope)); -  hashmap_put(&scope->vars, name, sc); -  return sc; -} - -static Initializer *new_initializer(Type *ty, bool is_flexible) { -  Initializer *init = calloc(1, sizeof(Initializer)); -  init->ty = ty; - -  if (ty->kind == TY_ARRAY) { -    if (is_flexible && ty->size < 0) { -      init->is_flexible = true; -      return init; -    } - -    init->children = calloc(ty->array_len, sizeof(Initializer *)); -    for (int i = 0; i < ty->array_len; i++) -      init->children[i] = new_initializer(ty->base, false); -    return init; -  } - -  if (ty->kind == TY_STRUCT || ty->kind == TY_UNION) { -    // Count the number of struct members. -    int len = 0; -    for (Member *mem = ty->members; mem; mem = mem->next) -      len++; - -    init->children = calloc(len, sizeof(Initializer *)); - -    for (Member *mem = ty->members; mem; mem = mem->next) { -      if (is_flexible && ty->is_flexible && !mem->next) { -        Initializer *child = calloc(1, sizeof(Initializer)); -        child->ty = mem->ty; -        child->is_flexible = true; -        init->children[mem->idx] = child; -      } else { -        init->children[mem->idx] = new_initializer(mem->ty, false); -      } -    } -    return init; -  } - -  return init; -} - -static Obj *new_var(char *name, Type *ty) { -  Obj *var = calloc(1, sizeof(Obj)); -  var->name = name; -  var->ty = ty; -  var->align = ty->align; -  push_scope(name)->var = var; -  return var; -} - -static Obj *new_lvar(char *name, Type *ty) { -  Obj *var = new_var(name, ty); -  var->is_local = true; -  var->next = locals; -  locals = var; -  return var; -} - -static Obj *new_gvar(char *name, Type *ty) { -  Obj *var = new_var(name, ty); -  var->next = globals; -  var->is_static = true; -  var->is_definition = true; -  globals = var; -  return var; -} - -static char *new_unique_name(void) { -  static int id = 0; -  return format(".L..%d", id++); -} - -static Obj *new_anon_gvar(Type *ty) { -  return new_gvar(new_unique_name(), ty); -} - -static Obj *new_string_literal(char *p, Type *ty) { -  Obj *var = new_anon_gvar(ty); -  var->init_data = p; -  return var; -} - -static char *get_ident(Token *tok) { -  if (tok->kind != TK_IDENT) -    error_tok(tok, "expected an identifier"); -  return strndup(tok->loc, tok->len); -} - -static Type *find_typedef(Token *tok) { -  if (tok->kind == TK_IDENT) { -    VarScope *sc = find_var(tok); -    if (sc) -      return sc->type_def; -  } -  return NULL; -} - -static void push_tag_scope(Token *tok, Type *ty) { -  hashmap_put2(&scope->tags, tok->loc, tok->len, ty); -} - -// declspec = ("void" | "_Bool" | "char" | "short" | "int" | "long" -//             | "typedef" | "static" | "extern" | "inline" -//             | "_Thread_local" | "__thread" -//             | "signed" | "unsigned" -//             | struct-decl | union-decl | typedef-name -//             | enum-specifier | typeof-specifier -//             | "const" | "volatile" | "auto" | "register" | "restrict" -//             | "__restrict" | "__restrict__" | "_Noreturn")+ -// -// The order of typenames in a type-specifier doesn't matter. For -// example, `int long static` means the same as `static long int`. -// That can also be written as `static long` because you can omit -// `int` if `long` or `short` are specified. However, something like -// `char int` is not a valid type specifier. We have to accept only a -// limited combinations of the typenames. -// -// In this function, we count the number of occurrences of each typename -// while keeping the "current" type object that the typenames up -// until that point represent. When we reach a non-typename token, -// we returns the current type object. -static Type *declspec(Token **rest, Token *tok, VarAttr *attr) { -  // We use a single integer as counters for all typenames. -  // For example, bits 0 and 1 represents how many times we saw the -  // keyword "void" so far. With this, we can use a switch statement -  // as you can see below. -  enum { -    VOID     = 1 << 0, -    BOOL     = 1 << 2, -    CHAR     = 1 << 4, -    SHORT    = 1 << 6, -    INT      = 1 << 8, -    LONG     = 1 << 10, -    FLOAT    = 1 << 12, -    DOUBLE   = 1 << 14, -    OTHER    = 1 << 16, -    SIGNED   = 1 << 17, -    UNSIGNED = 1 << 18, -  }; - -  Type *ty = ty_int; -  int counter = 0; -  bool is_atomic = false; - -  while (is_typename(tok)) { -    // Handle storage class specifiers. -    if (equal(tok, "typedef") || equal(tok, "static") || equal(tok, "extern") || -        equal(tok, "inline") || equal(tok, "_Thread_local") || equal(tok, "__thread")) { -      if (!attr) -        error_tok(tok, "storage class specifier is not allowed in this context"); - -      if (equal(tok, "typedef")) -        attr->is_typedef = true; -      else if (equal(tok, "static")) -        attr->is_static = true; -      else if (equal(tok, "extern")) -        attr->is_extern = true; -      else if (equal(tok, "inline")) -        attr->is_inline = true; -      else -        attr->is_tls = true; - -      if (attr->is_typedef && -          attr->is_static + attr->is_extern + attr->is_inline + attr->is_tls > 1) -        error_tok(tok, "typedef may not be used together with static," -                  " extern, inline, __thread or _Thread_local"); -      tok = tok->next; -      continue; -    } - -    // These keywords are recognized but ignored. -    if (consume(&tok, tok, "const") || consume(&tok, tok, "volatile") || -        consume(&tok, tok, "auto") || consume(&tok, tok, "register") || -        consume(&tok, tok, "restrict") || consume(&tok, tok, "__restrict") || -        consume(&tok, tok, "__restrict__") || consume(&tok, tok, "_Noreturn")) -      continue; - -    if (equal(tok, "_Atomic")) { -      tok = tok->next; -      if (equal(tok , "(")) { -        ty = typename(&tok, tok->next); -        tok = skip(tok, ")"); -      } -      is_atomic = true; -      continue; -    } - -    if (equal(tok, "_Alignas")) { -      if (!attr) -        error_tok(tok, "_Alignas is not allowed in this context"); -      tok = skip(tok->next, "("); - -      if (is_typename(tok)) -        attr->align = typename(&tok, tok)->align; -      else -        attr->align = const_expr(&tok, tok); -      tok = skip(tok, ")"); -      continue; -    } - -    // Handle user-defined types. -    Type *ty2 = find_typedef(tok); -    if (equal(tok, "struct") || equal(tok, "union") || equal(tok, "enum") || -        equal(tok, "typeof") || ty2) { -      if (counter) -        break; - -      if (equal(tok, "struct")) { -        ty = struct_decl(&tok, tok->next); -      } else if (equal(tok, "union")) { -        ty = union_decl(&tok, tok->next); -      } else if (equal(tok, "enum")) { -        ty = enum_specifier(&tok, tok->next); -      } else if (equal(tok, "typeof")) { -        ty = typeof_specifier(&tok, tok->next); -      } else { -        ty = ty2; -        tok = tok->next; -      } - -      counter += OTHER; -      continue; -    } - -    // Handle built-in types. -    if (equal(tok, "void")) -      counter += VOID; -    else if (equal(tok, "_Bool")) -      counter += BOOL; -    else if (equal(tok, "char")) -      counter += CHAR; -    else if (equal(tok, "short")) -      counter += SHORT; -    else if (equal(tok, "int")) -      counter += INT; -    else if (equal(tok, "long")) -      counter += LONG; -    else if (equal(tok, "float")) -      counter += FLOAT; -    else if (equal(tok, "double")) -      counter += DOUBLE; -    else if (equal(tok, "signed")) -      counter |= SIGNED; -    else if (equal(tok, "unsigned")) -      counter |= UNSIGNED; -    else -      unreachable(); - -    switch (counter) { -    case VOID: -      ty = ty_void; -      break; -    case BOOL: -      ty = ty_bool; -      break; -    case CHAR: -    case SIGNED + CHAR: -      ty = ty_char; -      break; -    case UNSIGNED + CHAR: -      ty = ty_uchar; -      break; -    case SHORT: -    case SHORT + INT: -    case SIGNED + SHORT: -    case SIGNED + SHORT + INT: -      ty = ty_short; -      break; -    case UNSIGNED + SHORT: -    case UNSIGNED + SHORT + INT: -      ty = ty_ushort; -      break; -    case INT: -    case SIGNED: -    case SIGNED + INT: -      ty = ty_int; -      break; -    case UNSIGNED: -    case UNSIGNED + INT: -      ty = ty_uint; -      break; -    case LONG: -    case LONG + INT: -    case LONG + LONG: -    case LONG + LONG + INT: -    case SIGNED + LONG: -    case SIGNED + LONG + INT: -    case SIGNED + LONG + LONG: -    case SIGNED + LONG + LONG + INT: -      ty = ty_long; -      break; -    case UNSIGNED + LONG: -    case UNSIGNED + LONG + INT: -    case UNSIGNED + LONG + LONG: -    case UNSIGNED + LONG + LONG + INT: -      ty = ty_ulong; -      break; -    case FLOAT: -      ty = ty_float; -      break; -    case DOUBLE: -      ty = ty_double; -      break; -    case LONG + DOUBLE: -      ty = ty_ldouble; -      break; -    default: -      error_tok(tok, "invalid type"); -    } - -    tok = tok->next; -  } - -  if (is_atomic) { -    ty = copy_type(ty); -    ty->is_atomic = true; -  } - -  *rest = tok; -  return ty; -} - -// func-params = ("void" | param ("," param)* ("," "...")?)? ")" -// param       = declspec declarator -static Type *func_params(Token **rest, Token *tok, Type *ty) { -  if (equal(tok, "void") && equal(tok->next, ")")) { -    *rest = tok->next->next; -    return func_type(ty); -  } - -  Type head = {}; -  Type *cur = &head; -  bool is_variadic = false; - -  while (!equal(tok, ")")) { -    if (cur != &head) -      tok = skip(tok, ","); - -    if (equal(tok, "...")) { -      is_variadic = true; -      tok = tok->next; -      skip(tok, ")"); -      break; -    } - -    Type *ty2 = declspec(&tok, tok, NULL); -    ty2 = declarator(&tok, tok, ty2); - -    Token *name = ty2->name; - -    if (ty2->kind == TY_ARRAY) { -      // "array of T" is converted to "pointer to T" only in the parameter -      // context. For example, *argv[] is converted to **argv by this. -      ty2 = pointer_to(ty2->base); -      ty2->name = name; -    } else if (ty2->kind == TY_FUNC) { -      // Likewise, a function is converted to a pointer to a function -      // only in the parameter context. -      ty2 = pointer_to(ty2); -      ty2->name = name; -    } - -    cur = cur->next = copy_type(ty2); -  } - -  if (cur == &head) -    is_variadic = true; - -  ty = func_type(ty); -  ty->params = head.next; -  ty->is_variadic = is_variadic; -  *rest = tok->next; -  return ty; -} - -// array-dimensions = ("static" | "restrict")* const-expr? "]" type-suffix -static Type *array_dimensions(Token **rest, Token *tok, Type *ty) { -  while (equal(tok, "static") || equal(tok, "restrict")) -    tok = tok->next; - -  if (equal(tok, "]")) { -    ty = type_suffix(rest, tok->next, ty); -    return array_of(ty, -1); -  } - -  Node *expr = conditional(&tok, tok); -  tok = skip(tok, "]"); -  ty = type_suffix(rest, tok, ty); - -  if (ty->kind == TY_VLA || !is_const_expr(expr)) -    return vla_of(ty, expr); -  return array_of(ty, eval(expr)); -} - -// type-suffix = "(" func-params -//             | "[" array-dimensions -//             | ε -static Type *type_suffix(Token **rest, Token *tok, Type *ty) { -  if (equal(tok, "(")) -    return func_params(rest, tok->next, ty); - -  if (equal(tok, "[")) -    return array_dimensions(rest, tok->next, ty); - -  *rest = tok; -  return ty; -} - -// pointers = ("*" ("const" | "volatile" | "restrict")*)* -static Type *pointers(Token **rest, Token *tok, Type *ty) { -  while (consume(&tok, tok, "*")) { -    ty = pointer_to(ty); -    while (equal(tok, "const") || equal(tok, "volatile") || equal(tok, "restrict") || -           equal(tok, "__restrict") || equal(tok, "__restrict__")) -      tok = tok->next; -  } -  *rest = tok; -  return ty; -} - -// declarator = pointers ("(" ident ")" | "(" declarator ")" | ident) type-suffix -static Type *declarator(Token **rest, Token *tok, Type *ty) { -  ty = pointers(&tok, tok, ty); - -  if (equal(tok, "(")) { -    Token *start = tok; -    Type dummy = {}; -    declarator(&tok, start->next, &dummy); -    tok = skip(tok, ")"); -    ty = type_suffix(rest, tok, ty); -    return declarator(&tok, start->next, ty); -  } - -  Token *name = NULL; -  Token *name_pos = tok; - -  if (tok->kind == TK_IDENT) { -    name = tok; -    tok = tok->next; -  } - -  ty = type_suffix(rest, tok, ty); -  ty->name = name; -  ty->name_pos = name_pos; -  return ty; -} - -// abstract-declarator = pointers ("(" abstract-declarator ")")? type-suffix -static Type *abstract_declarator(Token **rest, Token *tok, Type *ty) { -  ty = pointers(&tok, tok, ty); - -  if (equal(tok, "(")) { -    Token *start = tok; -    Type dummy = {}; -    abstract_declarator(&tok, start->next, &dummy); -    tok = skip(tok, ")"); -    ty = type_suffix(rest, tok, ty); -    return abstract_declarator(&tok, start->next, ty); -  } - -  return type_suffix(rest, tok, ty); -} - -// type-name = declspec abstract-declarator -static Type *typename(Token **rest, Token *tok) { -  Type *ty = declspec(&tok, tok, NULL); -  return abstract_declarator(rest, tok, ty); -} - -static bool is_end(Token *tok) { -  return equal(tok, "}") || (equal(tok, ",") && equal(tok->next, "}")); -} - -static bool consume_end(Token **rest, Token *tok) { -  if (equal(tok, "}")) { -    *rest = tok->next; -    return true; -  } - -  if (equal(tok, ",") && equal(tok->next, "}")) { -    *rest = tok->next->next; -    return true; -  } - -  return false; -} - -// enum-specifier = ident? "{" enum-list? "}" -//                | ident ("{" enum-list? "}")? -// -// enum-list      = ident ("=" num)? ("," ident ("=" num)?)* ","? -static Type *enum_specifier(Token **rest, Token *tok) { -  Type *ty = enum_type(); - -  // Read a struct tag. -  Token *tag = NULL; -  if (tok->kind == TK_IDENT) { -    tag = tok; -    tok = tok->next; -  } - -  if (tag && !equal(tok, "{")) { -    Type *ty = find_tag(tag); -    if (!ty) -      error_tok(tag, "unknown enum type"); -    if (ty->kind != TY_ENUM) -      error_tok(tag, "not an enum tag"); -    *rest = tok; -    return ty; -  } - -  tok = skip(tok, "{"); - -  // Read an enum-list. -  int i = 0; -  int val = 0; -  while (!consume_end(rest, tok)) { -    if (i++ > 0) -      tok = skip(tok, ","); - -    char *name = get_ident(tok); -    tok = tok->next; - -    if (equal(tok, "=")) -      val = const_expr(&tok, tok->next); - -    VarScope *sc = push_scope(name); -    sc->enum_ty = ty; -    sc->enum_val = val++; -  } - -  if (tag) -    push_tag_scope(tag, ty); -  return ty; -} - -// typeof-specifier = "(" (expr | typename) ")" -static Type *typeof_specifier(Token **rest, Token *tok) { -  tok = skip(tok, "("); - -  Type *ty; -  if (is_typename(tok)) { -    ty = typename(&tok, tok); -  } else { -    Node *node = expr(&tok, tok); -    add_type(node); -    ty = node->ty; -  } -  *rest = skip(tok, ")"); -  return ty; -} - -// Generate code for computing a VLA size. -static Node *compute_vla_size(Type *ty, Token *tok) { -  Node *node = new_node(ND_NULL_EXPR, tok); -  if (ty->base) -    node = new_binary(ND_COMMA, node, compute_vla_size(ty->base, tok), tok); - -  if (ty->kind != TY_VLA) -    return node; - -  Node *base_sz; -  if (ty->base->kind == TY_VLA) -    base_sz = new_var_node(ty->base->vla_size, tok); -  else -    base_sz = new_num(ty->base->size, tok); - -  ty->vla_size = new_lvar("", ty_ulong); -  Node *expr = new_binary(ND_ASSIGN, new_var_node(ty->vla_size, tok), -                          new_binary(ND_MUL, ty->vla_len, base_sz, tok), -                          tok); -  return new_binary(ND_COMMA, node, expr, tok); -} - -static Node *new_alloca(Node *sz) { -  Node *node = new_unary(ND_FUNCALL, new_var_node(builtin_alloca, sz->tok), sz->tok); -  node->func_ty = builtin_alloca->ty; -  node->ty = builtin_alloca->ty->return_ty; -  node->args = sz; -  add_type(sz); -  return node; -} - -// declaration = declspec (declarator ("=" expr)? ("," declarator ("=" expr)?)*)? ";" -static Node *declaration(Token **rest, Token *tok, Type *basety, VarAttr *attr) { -  Node head = {}; -  Node *cur = &head; -  int i = 0; - -  while (!equal(tok, ";")) { -    if (i++ > 0) -      tok = skip(tok, ","); - -    Type *ty = declarator(&tok, tok, basety); -    if (ty->kind == TY_VOID) -      error_tok(tok, "variable declared void"); -    if (!ty->name) -      error_tok(ty->name_pos, "variable name omitted"); - -    if (attr && attr->is_static) { -      // static local variable -      Obj *var = new_anon_gvar(ty); -      push_scope(get_ident(ty->name))->var = var; -      if (equal(tok, "=")) -        gvar_initializer(&tok, tok->next, var); -      continue; -    } - -    // Generate code for computing a VLA size. We need to do this -    // even if ty is not VLA because ty may be a pointer to VLA -    // (e.g. int (*foo)[n][m] where n and m are variables.) -    cur = cur->next = new_unary(ND_EXPR_STMT, compute_vla_size(ty, tok), tok); - -    if (ty->kind == TY_VLA) { -      if (equal(tok, "=")) -        error_tok(tok, "variable-sized object may not be initialized"); - -      // Variable length arrays (VLAs) are translated to alloca() calls. -      // For example, `int x[n+2]` is translated to `tmp = n + 2, -      // x = alloca(tmp)`. -      Obj *var = new_lvar(get_ident(ty->name), ty); -      Token *tok = ty->name; -      Node *expr = new_binary(ND_ASSIGN, new_vla_ptr(var, tok), -                              new_alloca(new_var_node(ty->vla_size, tok)), -                              tok); - -      cur = cur->next = new_unary(ND_EXPR_STMT, expr, tok); -      continue; -    } - -    Obj *var = new_lvar(get_ident(ty->name), ty); -    if (attr && attr->align) -      var->align = attr->align; - -    if (equal(tok, "=")) { -      Node *expr = lvar_initializer(&tok, tok->next, var); -      cur = cur->next = new_unary(ND_EXPR_STMT, expr, tok); -    } - -    if (var->ty->size < 0) -      error_tok(ty->name, "variable has incomplete type"); -    if (var->ty->kind == TY_VOID) -      error_tok(ty->name, "variable declared void"); -  } - -  Node *node = new_node(ND_BLOCK, tok); -  node->body = head.next; -  *rest = tok->next; -  return node; -} - -static Token *skip_excess_element(Token *tok) { -  if (equal(tok, "{")) { -    tok = skip_excess_element(tok->next); -    return skip(tok, "}"); -  } - -  assign(&tok, tok); -  return tok; -} - -// string-initializer = string-literal -static void string_initializer(Token **rest, Token *tok, Initializer *init) { -  if (init->is_flexible) -    *init = *new_initializer(array_of(init->ty->base, tok->ty->array_len), false); - -  int len = MIN(init->ty->array_len, tok->ty->array_len); - -  switch (init->ty->base->size) { -  case 1: { -    char *str = tok->str; -    for (int i = 0; i < len; i++) -      init->children[i]->expr = new_num(str[i], tok); -    break; -  } -  case 2: { -    uint16_t *str = (uint16_t *)tok->str; -    for (int i = 0; i < len; i++) -      init->children[i]->expr = new_num(str[i], tok); -    break; -  } -  case 4: { -    uint32_t *str = (uint32_t *)tok->str; -    for (int i = 0; i < len; i++) -      init->children[i]->expr = new_num(str[i], tok); -    break; -  } -  default: -    unreachable(); -  } - -  *rest = tok->next; -} - -// array-designator = "[" const-expr "]" -// -// C99 added the designated initializer to the language, which allows -// programmers to move the "cursor" of an initializer to any element. -// The syntax looks like this: -// -//   int x[10] = { 1, 2, [5]=3, 4, 5, 6, 7 }; -// -// `[5]` moves the cursor to the 5th element, so the 5th element of x -// is set to 3. Initialization then continues forward in order, so -// 6th, 7th, 8th and 9th elements are initialized with 4, 5, 6 and 7, -// respectively. Unspecified elements (in this case, 3rd and 4th -// elements) are initialized with zero. -// -// Nesting is allowed, so the following initializer is valid: -// -//   int x[5][10] = { [5][8]=1, 2, 3 }; -// -// It sets x[5][8], x[5][9] and x[6][0] to 1, 2 and 3, respectively. -// -// Use `.fieldname` to move the cursor for a struct initializer. E.g. -// -//   struct { int a, b, c; } x = { .c=5 }; -// -// The above initializer sets x.c to 5. -static void array_designator(Token **rest, Token *tok, Type *ty, int *begin, int *end) { -  *begin = const_expr(&tok, tok->next); -  if (*begin >= ty->array_len) -    error_tok(tok, "array designator index exceeds array bounds"); - -  if (equal(tok, "...")) { -    *end = const_expr(&tok, tok->next); -    if (*end >= ty->array_len) -      error_tok(tok, "array designator index exceeds array bounds"); -    if (*end < *begin) -      error_tok(tok, "array designator range [%d, %d] is empty", *begin, *end); -  } else { -    *end = *begin; -  } - -  *rest = skip(tok, "]"); -} - -// struct-designator = "." ident -static Member *struct_designator(Token **rest, Token *tok, Type *ty) { -  Token *start = tok; -  tok = skip(tok, "."); -  if (tok->kind != TK_IDENT) -    error_tok(tok, "expected a field designator"); - -  for (Member *mem = ty->members; mem; mem = mem->next) { -    // Anonymous struct member -    if (mem->ty->kind == TY_STRUCT && !mem->name) { -      if (get_struct_member(mem->ty, tok)) { -        *rest = start; -        return mem; -      } -      continue; -    } - -    // Regular struct member -    if (mem->name->len == tok->len && !strncmp(mem->name->loc, tok->loc, tok->len)) { -      *rest = tok->next; -      return mem; -    } -  } - -  error_tok(tok, "struct has no such member"); -} - -// designation = ("[" const-expr "]" | "." ident)* "="? initializer -static void designation(Token **rest, Token *tok, Initializer *init) { -  if (equal(tok, "[")) { -    if (init->ty->kind != TY_ARRAY) -      error_tok(tok, "array index in non-array initializer"); - -    int begin, end; -    array_designator(&tok, tok, init->ty, &begin, &end); - -    Token *tok2; -    for (int i = begin; i <= end; i++) -      designation(&tok2, tok, init->children[i]); -    array_initializer2(rest, tok2, init, begin + 1); -    return; -  } - -  if (equal(tok, ".") && init->ty->kind == TY_STRUCT) { -    Member *mem = struct_designator(&tok, tok, init->ty); -    designation(&tok, tok, init->children[mem->idx]); -    init->expr = NULL; -    struct_initializer2(rest, tok, init, mem->next); -    return; -  } - -  if (equal(tok, ".") && init->ty->kind == TY_UNION) { -    Member *mem = struct_designator(&tok, tok, init->ty); -    init->mem = mem; -    designation(rest, tok, init->children[mem->idx]); -    return; -  } - -  if (equal(tok, ".")) -    error_tok(tok, "field name not in struct or union initializer"); - -  if (equal(tok, "=")) -    tok = tok->next; -  initializer2(rest, tok, init); -} - -// An array length can be omitted if an array has an initializer -// (e.g. `int x[] = {1,2,3}`). If it's omitted, count the number -// of initializer elements. -static int count_array_init_elements(Token *tok, Type *ty) { -  bool first = true; -  Initializer *dummy = new_initializer(ty->base, true); - -  int i = 0, max = 0; - -  while (!consume_end(&tok, tok)) { -    if (!first) -      tok = skip(tok, ","); -    first = false; - -    if (equal(tok, "[")) { -      i = const_expr(&tok, tok->next); -      if (equal(tok, "...")) -        i = const_expr(&tok, tok->next); -      tok = skip(tok, "]"); -      designation(&tok, tok, dummy); -    } else { -      initializer2(&tok, tok, dummy); -    } - -    i++; -    max = MAX(max, i); -  } -  return max; -} - -// array-initializer1 = "{" initializer ("," initializer)* ","? "}" -static void array_initializer1(Token **rest, Token *tok, Initializer *init) { -  tok = skip(tok, "{"); - -  if (init->is_flexible) { -    int len = count_array_init_elements(tok, init->ty); -    *init = *new_initializer(array_of(init->ty->base, len), false); -  } - -  bool first = true; - -  if (init->is_flexible) { -    int len = count_array_init_elements(tok, init->ty); -    *init = *new_initializer(array_of(init->ty->base, len), false); -  } - -  for (int i = 0; !consume_end(rest, tok); i++) { -    if (!first) -      tok = skip(tok, ","); -    first = false; - -    if (equal(tok, "[")) { -      int begin, end; -      array_designator(&tok, tok, init->ty, &begin, &end); - -      Token *tok2; -      for (int j = begin; j <= end; j++) -        designation(&tok2, tok, init->children[j]); -      tok = tok2; -      i = end; -      continue; -    } - -    if (i < init->ty->array_len) -      initializer2(&tok, tok, init->children[i]); -    else -      tok = skip_excess_element(tok); -  } -} - -// array-initializer2 = initializer ("," initializer)* -static void array_initializer2(Token **rest, Token *tok, Initializer *init, int i) { -  if (init->is_flexible) { -    int len = count_array_init_elements(tok, init->ty); -    *init = *new_initializer(array_of(init->ty->base, len), false); -  } - -  for (; i < init->ty->array_len && !is_end(tok); i++) { -    Token *start = tok; -    if (i > 0) -      tok = skip(tok, ","); - -    if (equal(tok, "[") || equal(tok, ".")) { -      *rest = start; -      return; -    } - -    initializer2(&tok, tok, init->children[i]); -  } -  *rest = tok; -} - -// struct-initializer1 = "{" initializer ("," initializer)* ","? "}" -static void struct_initializer1(Token **rest, Token *tok, Initializer *init) { -  tok = skip(tok, "{"); - -  Member *mem = init->ty->members; -  bool first = true; - -  while (!consume_end(rest, tok)) { -    if (!first) -      tok = skip(tok, ","); -    first = false; - -    if (equal(tok, ".")) { -      mem = struct_designator(&tok, tok, init->ty); -      designation(&tok, tok, init->children[mem->idx]); -      mem = mem->next; -      continue; -    } - -    if (mem) { -      initializer2(&tok, tok, init->children[mem->idx]); -      mem = mem->next; -    } else { -      tok = skip_excess_element(tok); -    } -  } -} - -// struct-initializer2 = initializer ("," initializer)* -static void struct_initializer2(Token **rest, Token *tok, Initializer *init, Member *mem) { -  bool first = true; - -  for (; mem && !is_end(tok); mem = mem->next) { -    Token *start = tok; - -    if (!first) -      tok = skip(tok, ","); -    first = false; - -    if (equal(tok, "[") || equal(tok, ".")) { -      *rest = start; -      return; -    } - -    initializer2(&tok, tok, init->children[mem->idx]); -  } -  *rest = tok; -} - -static void union_initializer(Token **rest, Token *tok, Initializer *init) { -  // Unlike structs, union initializers take only one initializer, -  // and that initializes the first union member by default. -  // You can initialize other member using a designated initializer. -  if (equal(tok, "{") && equal(tok->next, ".")) { -    Member *mem = struct_designator(&tok, tok->next, init->ty); -    init->mem = mem; -    designation(&tok, tok, init->children[mem->idx]); -    *rest = skip(tok, "}"); -    return; -  } - -  init->mem = init->ty->members; - -  if (equal(tok, "{")) { -    initializer2(&tok, tok->next, init->children[0]); -    consume(&tok, tok, ","); -    *rest = skip(tok, "}"); -  } else { -    initializer2(rest, tok, init->children[0]); -  } -} - -// initializer = string-initializer | array-initializer -//             | struct-initializer | union-initializer -//             | assign -static void initializer2(Token **rest, Token *tok, Initializer *init) { -  if (init->ty->kind == TY_ARRAY && tok->kind == TK_STR) { -    string_initializer(rest, tok, init); -    return; -  } - -  if (init->ty->kind == TY_ARRAY) { -    if (equal(tok, "{")) -      array_initializer1(rest, tok, init); -    else -      array_initializer2(rest, tok, init, 0); -    return; -  } - -  if (init->ty->kind == TY_STRUCT) { -    if (equal(tok, "{")) { -      struct_initializer1(rest, tok, init); -      return; -    } - -    // A struct can be initialized with another struct. E.g. -    // `struct T x = y;` where y is a variable of type `struct T`. -    // Handle that case first. -    Node *expr = assign(rest, tok); -    add_type(expr); -    if (expr->ty->kind == TY_STRUCT) { -      init->expr = expr; -      return; -    } - -    struct_initializer2(rest, tok, init, init->ty->members); -    return; -  } - -  if (init->ty->kind == TY_UNION) { -    union_initializer(rest, tok, init); -    return; -  } - -  if (equal(tok, "{")) { -    // An initializer for a scalar variable can be surrounded by -    // braces. E.g. `int x = {3};`. Handle that case. -    initializer2(&tok, tok->next, init); -    *rest = skip(tok, "}"); -    return; -  } - -  init->expr = assign(rest, tok); -} - -static Type *copy_struct_type(Type *ty) { -  ty = copy_type(ty); - -  Member head = {}; -  Member *cur = &head; -  for (Member *mem = ty->members; mem; mem = mem->next) { -    Member *m = calloc(1, sizeof(Member)); -    *m = *mem; -    cur = cur->next = m; -  } - -  ty->members = head.next; -  return ty; -} - -static Initializer *initializer(Token **rest, Token *tok, Type *ty, Type **new_ty) { -  Initializer *init = new_initializer(ty, true); -  initializer2(rest, tok, init); - -  if ((ty->kind == TY_STRUCT || ty->kind == TY_UNION) && ty->is_flexible) { -    ty = copy_struct_type(ty); - -    Member *mem = ty->members; -    while (mem->next) -      mem = mem->next; -    mem->ty = init->children[mem->idx]->ty; -    ty->size += mem->ty->size; - -    *new_ty = ty; -    return init; -  } - -  *new_ty = init->ty; -  return init; -} - -static Node *init_desg_expr(InitDesg *desg, Token *tok) { -  if (desg->var) -    return new_var_node(desg->var, tok); - -  if (desg->member) { -    Node *node = new_unary(ND_MEMBER, init_desg_expr(desg->next, tok), tok); -    node->member = desg->member; -    return node; -  } - -  Node *lhs = init_desg_expr(desg->next, tok); -  Node *rhs = new_num(desg->idx, tok); -  return new_unary(ND_DEREF, new_add(lhs, rhs, tok), tok); -} - -static Node *create_lvar_init(Initializer *init, Type *ty, InitDesg *desg, Token *tok) { -  if (ty->kind == TY_ARRAY) { -    Node *node = new_node(ND_NULL_EXPR, tok); -    for (int i = 0; i < ty->array_len; i++) { -      InitDesg desg2 = {desg, i}; -      Node *rhs = create_lvar_init(init->children[i], ty->base, &desg2, tok); -      node = new_binary(ND_COMMA, node, rhs, tok); -    } -    return node; -  } - -  if (ty->kind == TY_STRUCT && !init->expr) { -    Node *node = new_node(ND_NULL_EXPR, tok); - -    for (Member *mem = ty->members; mem; mem = mem->next) { -      InitDesg desg2 = {desg, 0, mem}; -      Node *rhs = create_lvar_init(init->children[mem->idx], mem->ty, &desg2, tok); -      node = new_binary(ND_COMMA, node, rhs, tok); -    } -    return node; -  } - -  if (ty->kind == TY_UNION) { -    Member *mem = init->mem ? init->mem : ty->members; -    InitDesg desg2 = {desg, 0, mem}; -    return create_lvar_init(init->children[mem->idx], mem->ty, &desg2, tok); -  } - -  if (!init->expr) -    return new_node(ND_NULL_EXPR, tok); - -  Node *lhs = init_desg_expr(desg, tok); -  return new_binary(ND_ASSIGN, lhs, init->expr, tok); -} - -// A variable definition with an initializer is a shorthand notation -// for a variable definition followed by assignments. This function -// generates assignment expressions for an initializer. For example, -// `int x[2][2] = {{6, 7}, {8, 9}}` is converted to the following -// expressions: -// -//   x[0][0] = 6; -//   x[0][1] = 7; -//   x[1][0] = 8; -//   x[1][1] = 9; -static Node *lvar_initializer(Token **rest, Token *tok, Obj *var) { -  Initializer *init = initializer(rest, tok, var->ty, &var->ty); -  InitDesg desg = {NULL, 0, NULL, var}; - -  // If a partial initializer list is given, the standard requires -  // that unspecified elements are set to 0. Here, we simply -  // zero-initialize the entire memory region of a variable before -  // initializing it with user-supplied values. -  Node *lhs = new_node(ND_MEMZERO, tok); -  lhs->var = var; - -  Node *rhs = create_lvar_init(init, var->ty, &desg, tok); -  return new_binary(ND_COMMA, lhs, rhs, tok); -} - -static uint64_t read_buf(char *buf, int sz) { -  if (sz == 1) -    return *buf; -  if (sz == 2) -    return *(uint16_t *)buf; -  if (sz == 4) -    return *(uint32_t *)buf; -  if (sz == 8) -    return *(uint64_t *)buf; -  unreachable(); -} - -static void write_buf(char *buf, uint64_t val, int sz) { -  if (sz == 1) -    *buf = val; -  else if (sz == 2) -    *(uint16_t *)buf = val; -  else if (sz == 4) -    *(uint32_t *)buf = val; -  else if (sz == 8) -    *(uint64_t *)buf = val; -  else -    unreachable(); -} - -static Relocation * -write_gvar_data(Relocation *cur, Initializer *init, Type *ty, char *buf, int offset) { -  if (ty->kind == TY_ARRAY) { -    int sz = ty->base->size; -    for (int i = 0; i < ty->array_len; i++) -      cur = write_gvar_data(cur, init->children[i], ty->base, buf, offset + sz * i); -    return cur; -  } - -  if (ty->kind == TY_STRUCT) { -    for (Member *mem = ty->members; mem; mem = mem->next) { -      if (mem->is_bitfield) { -        Node *expr = init->children[mem->idx]->expr; -        if (!expr) -          break; - -        char *loc = buf + offset + mem->offset; -        uint64_t oldval = read_buf(loc, mem->ty->size); -        uint64_t newval = eval(expr); -        uint64_t mask = (1L << mem->bit_width) - 1; -        uint64_t combined = oldval | ((newval & mask) << mem->bit_offset); -        write_buf(loc, combined, mem->ty->size); -      } else { -        cur = write_gvar_data(cur, init->children[mem->idx], mem->ty, buf, -                              offset + mem->offset); -      } -    } -    return cur; -  } - -  if (ty->kind == TY_UNION) { -    if (!init->mem) -      return cur; -    return write_gvar_data(cur, init->children[init->mem->idx], -                           init->mem->ty, buf, offset); -  } - -  if (!init->expr) -    return cur; - -  if (ty->kind == TY_FLOAT) { -    *(float *)(buf + offset) = eval_double(init->expr); -    return cur; -  } - -  if (ty->kind == TY_DOUBLE) { -    *(double *)(buf + offset) = eval_double(init->expr); -    return cur; -  } - -  char **label = NULL; -  uint64_t val = eval2(init->expr, &label); - -  if (!label) { -    write_buf(buf + offset, val, ty->size); -    return cur; -  } - -  Relocation *rel = calloc(1, sizeof(Relocation)); -  rel->offset = offset; -  rel->label = label; -  rel->addend = val; -  cur->next = rel; -  return cur->next; -} - -// Initializers for global variables are evaluated at compile-time and -// embedded to .data section. This function serializes Initializer -// objects to a flat byte array. It is a compile error if an -// initializer list contains a non-constant expression. -static void gvar_initializer(Token **rest, Token *tok, Obj *var) { -  Initializer *init = initializer(rest, tok, var->ty, &var->ty); - -  Relocation head = {}; -  char *buf = calloc(1, var->ty->size); -  write_gvar_data(&head, init, var->ty, buf, 0); -  var->init_data = buf; -  var->rel = head.next; -} - -// Returns true if a given token represents a type. -static bool is_typename(Token *tok) { -  static HashMap map; - -  if (map.capacity == 0) { -    static char *kw[] = { -      "void", "_Bool", "char", "short", "int", "long", "struct", "union", -      "typedef", "enum", "static", "extern", "_Alignas", "signed", "unsigned", -      "const", "volatile", "auto", "register", "restrict", "__restrict", -      "__restrict__", "_Noreturn", "float", "double", "typeof", "inline", -      "_Thread_local", "__thread", "_Atomic", -    }; - -    for (int i = 0; i < sizeof(kw) / sizeof(*kw); i++) -      hashmap_put(&map, kw[i], (void *)1); -  } - -  return hashmap_get2(&map, tok->loc, tok->len) || find_typedef(tok); -} - -// asm-stmt = "asm" ("volatile" | "inline")* "(" string-literal ")" -static Node *asm_stmt(Token **rest, Token *tok) { -  Node *node = new_node(ND_ASM, tok); -  tok = tok->next; - -  while (equal(tok, "volatile") || equal(tok, "inline")) -    tok = tok->next; - -  tok = skip(tok, "("); -  if (tok->kind != TK_STR || tok->ty->base->kind != TY_CHAR) -    error_tok(tok, "expected string literal"); -  node->asm_str = tok->str; -  *rest = skip(tok->next, ")"); -  return node; -} - -// stmt = "return" expr? ";" -//      | "if" "(" expr ")" stmt ("else" stmt)? -//      | "switch" "(" expr ")" stmt -//      | "case" const-expr ("..." const-expr)? ":" stmt -//      | "default" ":" stmt -//      | "for" "(" expr-stmt expr? ";" expr? ")" stmt -//      | "while" "(" expr ")" stmt -//      | "do" stmt "while" "(" expr ")" ";" -//      | "asm" asm-stmt -//      | "goto" (ident | "*" expr) ";" -//      | "break" ";" -//      | "continue" ";" -//      | ident ":" stmt -//      | "{" compound-stmt -//      | expr-stmt -static Node *stmt(Token **rest, Token *tok) { -  if (equal(tok, "return")) { -    Node *node = new_node(ND_RETURN, tok); -    if (consume(rest, tok->next, ";")) -      return node; - -    Node *exp = expr(&tok, tok->next); -    *rest = skip(tok, ";"); - -    add_type(exp); -    Type *ty = current_fn->ty->return_ty; -    if (ty->kind != TY_STRUCT && ty->kind != TY_UNION) -      exp = new_cast(exp, current_fn->ty->return_ty); - -    node->lhs = exp; -    return node; -  } - -  if (equal(tok, "if")) { -    Node *node = new_node(ND_IF, tok); -    tok = skip(tok->next, "("); -    node->cond = expr(&tok, tok); -    tok = skip(tok, ")"); -    node->then = stmt(&tok, tok); -    if (equal(tok, "else")) -      node->els = stmt(&tok, tok->next); -    *rest = tok; -    return node; -  } - -  if (equal(tok, "switch")) { -    Node *node = new_node(ND_SWITCH, tok); -    tok = skip(tok->next, "("); -    node->cond = expr(&tok, tok); -    tok = skip(tok, ")"); - -    Node *sw = current_switch; -    current_switch = node; - -    char *brk = brk_label; -    brk_label = node->brk_label = new_unique_name(); - -    node->then = stmt(rest, tok); - -    current_switch = sw; -    brk_label = brk; -    return node; -  } - -  if (equal(tok, "case")) { -    if (!current_switch) -      error_tok(tok, "stray case"); - -    Node *node = new_node(ND_CASE, tok); -    int begin = const_expr(&tok, tok->next); -    int end; - -    if (equal(tok, "...")) { -      // [GNU] Case ranges, e.g. "case 1 ... 5:" -      end = const_expr(&tok, tok->next); -      if (end < begin) -        error_tok(tok, "empty case range specified"); -    } else { -      end = begin; -    } - -    tok = skip(tok, ":"); -    node->label = new_unique_name(); -    node->lhs = stmt(rest, tok); -    node->begin = begin; -    node->end = end; -    node->case_next = current_switch->case_next; -    current_switch->case_next = node; -    return node; -  } - -  if (equal(tok, "default")) { -    if (!current_switch) -      error_tok(tok, "stray default"); - -    Node *node = new_node(ND_CASE, tok); -    tok = skip(tok->next, ":"); -    node->label = new_unique_name(); -    node->lhs = stmt(rest, tok); -    current_switch->default_case = node; -    return node; -  } - -  if (equal(tok, "for")) { -    Node *node = new_node(ND_FOR, tok); -    tok = skip(tok->next, "("); - -    enter_scope(); - -    char *brk = brk_label; -    char *cont = cont_label; -    brk_label = node->brk_label = new_unique_name(); -    cont_label = node->cont_label = new_unique_name(); - -    if (is_typename(tok)) { -      Type *basety = declspec(&tok, tok, NULL); -      node->init = declaration(&tok, tok, basety, NULL); -    } else { -      node->init = expr_stmt(&tok, tok); -    } - -    if (!equal(tok, ";")) -      node->cond = expr(&tok, tok); -    tok = skip(tok, ";"); - -    if (!equal(tok, ")")) -      node->inc = expr(&tok, tok); -    tok = skip(tok, ")"); - -    node->then = stmt(rest, tok); - -    leave_scope(); -    brk_label = brk; -    cont_label = cont; -    return node; -  } - -  if (equal(tok, "while")) { -    Node *node = new_node(ND_FOR, tok); -    tok = skip(tok->next, "("); -    node->cond = expr(&tok, tok); -    tok = skip(tok, ")"); - -    char *brk = brk_label; -    char *cont = cont_label; -    brk_label = node->brk_label = new_unique_name(); -    cont_label = node->cont_label = new_unique_name(); - -    node->then = stmt(rest, tok); - -    brk_label = brk; -    cont_label = cont; -    return node; -  } - -  if (equal(tok, "do")) { -    Node *node = new_node(ND_DO, tok); - -    char *brk = brk_label; -    char *cont = cont_label; -    brk_label = node->brk_label = new_unique_name(); -    cont_label = node->cont_label = new_unique_name(); - -    node->then = stmt(&tok, tok->next); - -    brk_label = brk; -    cont_label = cont; - -    tok = skip(tok, "while"); -    tok = skip(tok, "("); -    node->cond = expr(&tok, tok); -    tok = skip(tok, ")"); -    *rest = skip(tok, ";"); -    return node; -  } - -  if (equal(tok, "asm")) -    return asm_stmt(rest, tok); - -  if (equal(tok, "goto")) { -    if (equal(tok->next, "*")) { -      // [GNU] `goto *ptr` jumps to the address specified by `ptr`. -      Node *node = new_node(ND_GOTO_EXPR, tok); -      node->lhs = expr(&tok, tok->next->next); -      *rest = skip(tok, ";"); -      return node; -    } - -    Node *node = new_node(ND_GOTO, tok); -    node->label = get_ident(tok->next); -    node->goto_next = gotos; -    gotos = node; -    *rest = skip(tok->next->next, ";"); -    return node; -  } - -  if (equal(tok, "break")) { -    if (!brk_label) -      error_tok(tok, "stray break"); -    Node *node = new_node(ND_GOTO, tok); -    node->unique_label = brk_label; -    *rest = skip(tok->next, ";"); -    return node; -  } - -  if (equal(tok, "continue")) { -    if (!cont_label) -      error_tok(tok, "stray continue"); -    Node *node = new_node(ND_GOTO, tok); -    node->unique_label = cont_label; -    *rest = skip(tok->next, ";"); -    return node; -  } - -  if (tok->kind == TK_IDENT && equal(tok->next, ":")) { -    Node *node = new_node(ND_LABEL, tok); -    node->label = strndup(tok->loc, tok->len); -    node->unique_label = new_unique_name(); -    node->lhs = stmt(rest, tok->next->next); -    node->goto_next = labels; -    labels = node; -    return node; -  } - -  if (equal(tok, "{")) -    return compound_stmt(rest, tok->next); - -  return expr_stmt(rest, tok); -} - -// compound-stmt = (typedef | declaration | stmt)* "}" -static Node *compound_stmt(Token **rest, Token *tok) { -  Node *node = new_node(ND_BLOCK, tok); -  Node head = {}; -  Node *cur = &head; - -  enter_scope(); - -  while (!equal(tok, "}")) { -    if (is_typename(tok) && !equal(tok->next, ":")) { -      VarAttr attr = {}; -      Type *basety = declspec(&tok, tok, &attr); - -      if (attr.is_typedef) { -        tok = parse_typedef(tok, basety); -        continue; -      } - -      if (is_function(tok)) { -        tok = function(tok, basety, &attr); -        continue; -      } - -      if (attr.is_extern) { -        tok = global_variable(tok, basety, &attr); -        continue; -      } - -      cur = cur->next = declaration(&tok, tok, basety, &attr); -    } else { -      cur = cur->next = stmt(&tok, tok); -    } -    add_type(cur); -  } - -  leave_scope(); - -  node->body = head.next; -  *rest = tok->next; -  return node; -} - -// expr-stmt = expr? ";" -static Node *expr_stmt(Token **rest, Token *tok) { -  if (equal(tok, ";")) { -    *rest = tok->next; -    return new_node(ND_BLOCK, tok); -  } - -  Node *node = new_node(ND_EXPR_STMT, tok); -  node->lhs = expr(&tok, tok); -  *rest = skip(tok, ";"); -  return node; -} - -// expr = assign ("," expr)? -static Node *expr(Token **rest, Token *tok) { -  Node *node = assign(&tok, tok); - -  if (equal(tok, ",")) -    return new_binary(ND_COMMA, node, expr(rest, tok->next), tok); - -  *rest = tok; -  return node; -} - -static int64_t eval(Node *node) { -  return eval2(node, NULL); -} - -// Evaluate a given node as a constant expression. -// -// A constant expression is either just a number or ptr+n where ptr -// is a pointer to a global variable and n is a postiive/negative -// number. The latter form is accepted only as an initialization -// expression for a global variable. -static int64_t eval2(Node *node, char ***label) { -  add_type(node); - -  if (is_flonum(node->ty)) -    return eval_double(node); - -  switch (node->kind) { -  case ND_ADD: -    return eval2(node->lhs, label) + eval(node->rhs); -  case ND_SUB: -    return eval2(node->lhs, label) - eval(node->rhs); -  case ND_MUL: -    return eval(node->lhs) * eval(node->rhs); -  case ND_DIV: -    if (node->ty->is_unsigned) -      return (uint64_t)eval(node->lhs) / eval(node->rhs); -    return eval(node->lhs) / eval(node->rhs); -  case ND_NEG: -    return -eval(node->lhs); -  case ND_MOD: -    if (node->ty->is_unsigned) -      return (uint64_t)eval(node->lhs) % eval(node->rhs); -    return eval(node->lhs) % eval(node->rhs); -  case ND_BITAND: -    return eval(node->lhs) & eval(node->rhs); -  case ND_BITOR: -    return eval(node->lhs) | eval(node->rhs); -  case ND_BITXOR: -    return eval(node->lhs) ^ eval(node->rhs); -  case ND_SHL: -    return eval(node->lhs) << eval(node->rhs); -  case ND_SHR: -    if (node->ty->is_unsigned && node->ty->size == 8) -      return (uint64_t)eval(node->lhs) >> eval(node->rhs); -    return eval(node->lhs) >> eval(node->rhs); -  case ND_EQ: -    return eval(node->lhs) == eval(node->rhs); -  case ND_NE: -    return eval(node->lhs) != eval(node->rhs); -  case ND_LT: -    if (node->lhs->ty->is_unsigned) -      return (uint64_t)eval(node->lhs) < eval(node->rhs); -    return eval(node->lhs) < eval(node->rhs); -  case ND_LE: -    if (node->lhs->ty->is_unsigned) -      return (uint64_t)eval(node->lhs) <= eval(node->rhs); -    return eval(node->lhs) <= eval(node->rhs); -  case ND_COND: -    return eval(node->cond) ? eval2(node->then, label) : eval2(node->els, label); -  case ND_COMMA: -    return eval2(node->rhs, label); -  case ND_NOT: -    return !eval(node->lhs); -  case ND_BITNOT: -    return ~eval(node->lhs); -  case ND_LOGAND: -    return eval(node->lhs) && eval(node->rhs); -  case ND_LOGOR: -    return eval(node->lhs) || eval(node->rhs); -  case ND_CAST: { -    int64_t val = eval2(node->lhs, label); -    if (is_integer(node->ty)) { -      switch (node->ty->size) { -      case 1: return node->ty->is_unsigned ? (uint8_t)val : (int8_t)val; -      case 2: return node->ty->is_unsigned ? (uint16_t)val : (int16_t)val; -      case 4: return node->ty->is_unsigned ? (uint32_t)val : (int32_t)val; -      } -    } -    return val; -  } -  case ND_ADDR: -    return eval_rval(node->lhs, label); -  case ND_LABEL_VAL: -    *label = &node->unique_label; -    return 0; -  case ND_MEMBER: -    if (!label) -      error_tok(node->tok, "not a compile-time constant"); -    if (node->ty->kind != TY_ARRAY) -      error_tok(node->tok, "invalid initializer"); -    return eval_rval(node->lhs, label) + node->member->offset; -  case ND_VAR: -    if (!label) -      error_tok(node->tok, "not a compile-time constant"); -    if (node->var->ty->kind != TY_ARRAY && node->var->ty->kind != TY_FUNC) -      error_tok(node->tok, "invalid initializer"); -    *label = &node->var->name; -    return 0; -  case ND_NUM: -    return node->val; -  } - -  error_tok(node->tok, "not a compile-time constant"); -} - -static int64_t eval_rval(Node *node, char ***label) { -  switch (node->kind) { -  case ND_VAR: -    if (node->var->is_local) -      error_tok(node->tok, "not a compile-time constant"); -    *label = &node->var->name; -    return 0; -  case ND_DEREF: -    return eval2(node->lhs, label); -  case ND_MEMBER: -    return eval_rval(node->lhs, label) + node->member->offset; -  } - -  error_tok(node->tok, "invalid initializer"); -} - -static bool is_const_expr(Node *node) { -  add_type(node); - -  switch (node->kind) { -  case ND_ADD: -  case ND_SUB: -  case ND_MUL: -  case ND_DIV: -  case ND_BITAND: -  case ND_BITOR: -  case ND_BITXOR: -  case ND_SHL: -  case ND_SHR: -  case ND_EQ: -  case ND_NE: -  case ND_LT: -  case ND_LE: -  case ND_LOGAND: -  case ND_LOGOR: -    return is_const_expr(node->lhs) && is_const_expr(node->rhs); -  case ND_COND: -    if (!is_const_expr(node->cond)) -      return false; -    return is_const_expr(eval(node->cond) ? node->then : node->els); -  case ND_COMMA: -    return is_const_expr(node->rhs); -  case ND_NEG: -  case ND_NOT: -  case ND_BITNOT: -  case ND_CAST: -    return is_const_expr(node->lhs); -  case ND_NUM: -    return true; -  } - -  return false; -} - -int64_t const_expr(Token **rest, Token *tok) { -  Node *node = conditional(rest, tok); -  return eval(node); -} - -static double eval_double(Node *node) { -  add_type(node); - -  if (is_integer(node->ty)) { -    if (node->ty->is_unsigned) -      return (unsigned long)eval(node); -    return eval(node); -  } - -  switch (node->kind) { -  case ND_ADD: -    return eval_double(node->lhs) + eval_double(node->rhs); -  case ND_SUB: -    return eval_double(node->lhs) - eval_double(node->rhs); -  case ND_MUL: -    return eval_double(node->lhs) * eval_double(node->rhs); -  case ND_DIV: -    return eval_double(node->lhs) / eval_double(node->rhs); -  case ND_NEG: -    return -eval_double(node->lhs); -  case ND_COND: -    return eval_double(node->cond) ? eval_double(node->then) : eval_double(node->els); -  case ND_COMMA: -    return eval_double(node->rhs); -  case ND_CAST: -    if (is_flonum(node->lhs->ty)) -      return eval_double(node->lhs); -    return eval(node->lhs); -  case ND_NUM: -    return node->fval; -  } - -  error_tok(node->tok, "not a compile-time constant"); -} - -// Convert op= operators to expressions containing an assignment. -// -// In general, `A op= C` is converted to ``tmp = &A, *tmp = *tmp op B`. -// However, if a given expression is of form `A.x op= C`, the input is -// converted to `tmp = &A, (*tmp).x = (*tmp).x op C` to handle assignments -// to bitfields. -static Node *to_assign(Node *binary) { -  add_type(binary->lhs); -  add_type(binary->rhs); -  Token *tok = binary->tok; - -  // Convert `A.x op= C` to `tmp = &A, (*tmp).x = (*tmp).x op C`. -  if (binary->lhs->kind == ND_MEMBER) { -    Obj *var = new_lvar("", pointer_to(binary->lhs->lhs->ty)); - -    Node *expr1 = new_binary(ND_ASSIGN, new_var_node(var, tok), -                             new_unary(ND_ADDR, binary->lhs->lhs, tok), tok); - -    Node *expr2 = new_unary(ND_MEMBER, -                            new_unary(ND_DEREF, new_var_node(var, tok), tok), -                            tok); -    expr2->member = binary->lhs->member; - -    Node *expr3 = new_unary(ND_MEMBER, -                            new_unary(ND_DEREF, new_var_node(var, tok), tok), -                            tok); -    expr3->member = binary->lhs->member; - -    Node *expr4 = new_binary(ND_ASSIGN, expr2, -                             new_binary(binary->kind, expr3, binary->rhs, tok), -                             tok); - -    return new_binary(ND_COMMA, expr1, expr4, tok); -  } - -  // If A is an atomic type, Convert `A op= B` to -  // -  // ({ -  //   T1 *addr = &A; T2 val = (B); T1 old = *addr; T1 new; -  //   do { -  //    new = old op val; -  //   } while (!atomic_compare_exchange_strong(addr, &old, new)); -  //   new; -  // }) -  if (binary->lhs->ty->is_atomic) { -    Node head = {}; -    Node *cur = &head; - -    Obj *addr = new_lvar("", pointer_to(binary->lhs->ty)); -    Obj *val = new_lvar("", binary->rhs->ty); -    Obj *old = new_lvar("", binary->lhs->ty); -    Obj *new = new_lvar("", binary->lhs->ty); - -    cur = cur->next = -      new_unary(ND_EXPR_STMT, -                new_binary(ND_ASSIGN, new_var_node(addr, tok), -                           new_unary(ND_ADDR, binary->lhs, tok), tok), -                tok); - -    cur = cur->next = -      new_unary(ND_EXPR_STMT, -                new_binary(ND_ASSIGN, new_var_node(val, tok), binary->rhs, tok), -                tok); - -    cur = cur->next = -      new_unary(ND_EXPR_STMT, -                new_binary(ND_ASSIGN, new_var_node(old, tok), -                           new_unary(ND_DEREF, new_var_node(addr, tok), tok), tok), -                tok); - -    Node *loop = new_node(ND_DO, tok); -    loop->brk_label = new_unique_name(); -    loop->cont_label = new_unique_name(); - -    Node *body = new_binary(ND_ASSIGN, -                            new_var_node(new, tok), -                            new_binary(binary->kind, new_var_node(old, tok), -                                       new_var_node(val, tok), tok), -                            tok); - -    loop->then = new_node(ND_BLOCK, tok); -    loop->then->body = new_unary(ND_EXPR_STMT, body, tok); - -    Node *cas = new_node(ND_CAS, tok); -    cas->cas_addr = new_var_node(addr, tok); -    cas->cas_old = new_unary(ND_ADDR, new_var_node(old, tok), tok); -    cas->cas_new = new_var_node(new, tok); -    loop->cond = new_unary(ND_NOT, cas, tok); - -    cur = cur->next = loop; -    cur = cur->next = new_unary(ND_EXPR_STMT, new_var_node(new, tok), tok); - -    Node *node = new_node(ND_STMT_EXPR, tok); -    node->body = head.next; -    return node; -  } - -  // Convert `A op= B` to ``tmp = &A, *tmp = *tmp op B`. -  Obj *var = new_lvar("", pointer_to(binary->lhs->ty)); - -  Node *expr1 = new_binary(ND_ASSIGN, new_var_node(var, tok), -                           new_unary(ND_ADDR, binary->lhs, tok), tok); - -  Node *expr2 = -    new_binary(ND_ASSIGN, -               new_unary(ND_DEREF, new_var_node(var, tok), tok), -               new_binary(binary->kind, -                          new_unary(ND_DEREF, new_var_node(var, tok), tok), -                          binary->rhs, -                          tok), -               tok); - -  return new_binary(ND_COMMA, expr1, expr2, tok); -} - -// assign    = conditional (assign-op assign)? -// assign-op = "=" | "+=" | "-=" | "*=" | "/=" | "%=" | "&=" | "|=" | "^=" -//           | "<<=" | ">>=" -static Node *assign(Token **rest, Token *tok) { -  Node *node = conditional(&tok, tok); - -  if (equal(tok, "=")) -    return new_binary(ND_ASSIGN, node, assign(rest, tok->next), tok); - -  if (equal(tok, "+=")) -    return to_assign(new_add(node, assign(rest, tok->next), tok)); - -  if (equal(tok, "-=")) -    return to_assign(new_sub(node, assign(rest, tok->next), tok)); - -  if (equal(tok, "*=")) -    return to_assign(new_binary(ND_MUL, node, assign(rest, tok->next), tok)); - -  if (equal(tok, "/=")) -    return to_assign(new_binary(ND_DIV, node, assign(rest, tok->next), tok)); - -  if (equal(tok, "%=")) -    return to_assign(new_binary(ND_MOD, node, assign(rest, tok->next), tok)); - -  if (equal(tok, "&=")) -    return to_assign(new_binary(ND_BITAND, node, assign(rest, tok->next), tok)); - -  if (equal(tok, "|=")) -    return to_assign(new_binary(ND_BITOR, node, assign(rest, tok->next), tok)); - -  if (equal(tok, "^=")) -    return to_assign(new_binary(ND_BITXOR, node, assign(rest, tok->next), tok)); - -  if (equal(tok, "<<=")) -    return to_assign(new_binary(ND_SHL, node, assign(rest, tok->next), tok)); - -  if (equal(tok, ">>=")) -    return to_assign(new_binary(ND_SHR, node, assign(rest, tok->next), tok)); - -  *rest = tok; -  return node; -} - -// conditional = logor ("?" expr? ":" conditional)? -static Node *conditional(Token **rest, Token *tok) { -  Node *cond = logor(&tok, tok); - -  if (!equal(tok, "?")) { -    *rest = tok; -    return cond; -  } - -  if (equal(tok->next, ":")) { -    // [GNU] Compile `a ?: b` as `tmp = a, tmp ? tmp : b`. -    add_type(cond); -    Obj *var = new_lvar("", cond->ty); -    Node *lhs = new_binary(ND_ASSIGN, new_var_node(var, tok), cond, tok); -    Node *rhs = new_node(ND_COND, tok); -    rhs->cond = new_var_node(var, tok); -    rhs->then = new_var_node(var, tok); -    rhs->els = conditional(rest, tok->next->next); -    return new_binary(ND_COMMA, lhs, rhs, tok); -  } - -  Node *node = new_node(ND_COND, tok); -  node->cond = cond; -  node->then = expr(&tok, tok->next); -  tok = skip(tok, ":"); -  node->els = conditional(rest, tok); -  return node; -} - -// logor = logand ("||" logand)* -static Node *logor(Token **rest, Token *tok) { -  Node *node = logand(&tok, tok); -  while (equal(tok, "||")) { -    Token *start = tok; -    node = new_binary(ND_LOGOR, node, logand(&tok, tok->next), start); -  } -  *rest = tok; -  return node; -} - -// logand = bitor ("&&" bitor)* -static Node *logand(Token **rest, Token *tok) { -  Node *node = bitor(&tok, tok); -  while (equal(tok, "&&")) { -    Token *start = tok; -    node = new_binary(ND_LOGAND, node, bitor(&tok, tok->next), start); -  } -  *rest = tok; -  return node; -} - -// bitor = bitxor ("|" bitxor)* -static Node *bitor(Token **rest, Token *tok) { -  Node *node = bitxor(&tok, tok); -  while (equal(tok, "|")) { -    Token *start = tok; -    node = new_binary(ND_BITOR, node, bitxor(&tok, tok->next), start); -  } -  *rest = tok; -  return node; -} - -// bitxor = bitand ("^" bitand)* -static Node *bitxor(Token **rest, Token *tok) { -  Node *node = bitand(&tok, tok); -  while (equal(tok, "^")) { -    Token *start = tok; -    node = new_binary(ND_BITXOR, node, bitand(&tok, tok->next), start); -  } -  *rest = tok; -  return node; -} - -// bitand = equality ("&" equality)* -static Node *bitand(Token **rest, Token *tok) { -  Node *node = equality(&tok, tok); -  while (equal(tok, "&")) { -    Token *start = tok; -    node = new_binary(ND_BITAND, node, equality(&tok, tok->next), start); -  } -  *rest = tok; -  return node; -} - -// equality = relational ("==" relational | "!=" relational)* -static Node *equality(Token **rest, Token *tok) { -  Node *node = relational(&tok, tok); - -  for (;;) { -    Token *start = tok; - -    if (equal(tok, "==")) { -      node = new_binary(ND_EQ, node, relational(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, "!=")) { -      node = new_binary(ND_NE, node, relational(&tok, tok->next), start); -      continue; -    } - -    *rest = tok; -    return node; -  } -} - -// relational = shift ("<" shift | "<=" shift | ">" shift | ">=" shift)* -static Node *relational(Token **rest, Token *tok) { -  Node *node = shift(&tok, tok); - -  for (;;) { -    Token *start = tok; - -    if (equal(tok, "<")) { -      node = new_binary(ND_LT, node, shift(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, "<=")) { -      node = new_binary(ND_LE, node, shift(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, ">")) { -      node = new_binary(ND_LT, shift(&tok, tok->next), node, start); -      continue; -    } - -    if (equal(tok, ">=")) { -      node = new_binary(ND_LE, shift(&tok, tok->next), node, start); -      continue; -    } - -    *rest = tok; -    return node; -  } -} - -// shift = add ("<<" add | ">>" add)* -static Node *shift(Token **rest, Token *tok) { -  Node *node = add(&tok, tok); - -  for (;;) { -    Token *start = tok; - -    if (equal(tok, "<<")) { -      node = new_binary(ND_SHL, node, add(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, ">>")) { -      node = new_binary(ND_SHR, node, add(&tok, tok->next), start); -      continue; -    } - -    *rest = tok; -    return node; -  } -} - -// In C, `+` operator is overloaded to perform the pointer arithmetic. -// If p is a pointer, p+n adds not n but sizeof(*p)*n to the value of p, -// so that p+n points to the location n elements (not bytes) ahead of p. -// In other words, we need to scale an integer value before adding to a -// pointer value. This function takes care of the scaling. -static Node *new_add(Node *lhs, Node *rhs, Token *tok) { -  add_type(lhs); -  add_type(rhs); - -  // num + num -  if (is_numeric(lhs->ty) && is_numeric(rhs->ty)) -    return new_binary(ND_ADD, lhs, rhs, tok); - -  if (lhs->ty->base && rhs->ty->base) -    error_tok(tok, "invalid operands"); - -  // Canonicalize `num + ptr` to `ptr + num`. -  if (!lhs->ty->base && rhs->ty->base) { -    Node *tmp = lhs; -    lhs = rhs; -    rhs = tmp; -  } - -  // VLA + num -  if (lhs->ty->base->kind == TY_VLA) { -    rhs = new_binary(ND_MUL, rhs, new_var_node(lhs->ty->base->vla_size, tok), tok); -    return new_binary(ND_ADD, lhs, rhs, tok); -  } - -  // ptr + num -  rhs = new_binary(ND_MUL, rhs, new_long(lhs->ty->base->size, tok), tok); -  return new_binary(ND_ADD, lhs, rhs, tok); -} - -// Like `+`, `-` is overloaded for the pointer type. -static Node *new_sub(Node *lhs, Node *rhs, Token *tok) { -  add_type(lhs); -  add_type(rhs); - -  // num - num -  if (is_numeric(lhs->ty) && is_numeric(rhs->ty)) -    return new_binary(ND_SUB, lhs, rhs, tok); - -  // VLA + num -  if (lhs->ty->base->kind == TY_VLA) { -    rhs = new_binary(ND_MUL, rhs, new_var_node(lhs->ty->base->vla_size, tok), tok); -    add_type(rhs); -    Node *node = new_binary(ND_SUB, lhs, rhs, tok); -    node->ty = lhs->ty; -    return node; -  } - -  // ptr - num -  if (lhs->ty->base && is_integer(rhs->ty)) { -    rhs = new_binary(ND_MUL, rhs, new_long(lhs->ty->base->size, tok), tok); -    add_type(rhs); -    Node *node = new_binary(ND_SUB, lhs, rhs, tok); -    node->ty = lhs->ty; -    return node; -  } - -  // ptr - ptr, which returns how many elements are between the two. -  if (lhs->ty->base && rhs->ty->base) { -    Node *node = new_binary(ND_SUB, lhs, rhs, tok); -    node->ty = ty_long; -    return new_binary(ND_DIV, node, new_num(lhs->ty->base->size, tok), tok); -  } - -  error_tok(tok, "invalid operands"); -} - -// add = mul ("+" mul | "-" mul)* -static Node *add(Token **rest, Token *tok) { -  Node *node = mul(&tok, tok); - -  for (;;) { -    Token *start = tok; - -    if (equal(tok, "+")) { -      node = new_add(node, mul(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, "-")) { -      node = new_sub(node, mul(&tok, tok->next), start); -      continue; -    } - -    *rest = tok; -    return node; -  } -} - -// mul = cast ("*" cast | "/" cast | "%" cast)* -static Node *mul(Token **rest, Token *tok) { -  Node *node = cast(&tok, tok); - -  for (;;) { -    Token *start = tok; - -    if (equal(tok, "*")) { -      node = new_binary(ND_MUL, node, cast(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, "/")) { -      node = new_binary(ND_DIV, node, cast(&tok, tok->next), start); -      continue; -    } - -    if (equal(tok, "%")) { -      node = new_binary(ND_MOD, node, cast(&tok, tok->next), start); -      continue; -    } - -    *rest = tok; -    return node; -  } -} - -// cast = "(" type-name ")" cast | unary -static Node *cast(Token **rest, Token *tok) { -  if (equal(tok, "(") && is_typename(tok->next)) { -    Token *start = tok; -    Type *ty = typename(&tok, tok->next); -    tok = skip(tok, ")"); - -    // compound literal -    if (equal(tok, "{")) -      return unary(rest, start); - -    // type cast -    Node *node = new_cast(cast(rest, tok), ty); -    node->tok = start; -    return node; -  } - -  return unary(rest, tok); -} - -// unary = ("+" | "-" | "*" | "&" | "!" | "~") cast -//       | ("++" | "--") unary -//       | "&&" ident -//       | postfix -static Node *unary(Token **rest, Token *tok) { -  if (equal(tok, "+")) -    return cast(rest, tok->next); - -  if (equal(tok, "-")) -    return new_unary(ND_NEG, cast(rest, tok->next), tok); - -  if (equal(tok, "&")) { -    Node *lhs = cast(rest, tok->next); -    add_type(lhs); -    if (lhs->kind == ND_MEMBER && lhs->member->is_bitfield) -      error_tok(tok, "cannot take address of bitfield"); -    return new_unary(ND_ADDR, lhs, tok); -  } - -  if (equal(tok, "*")) { -    // [https://www.sigbus.info/n1570#6.5.3.2p4] This is an oddity -    // in the C spec, but dereferencing a function shouldn't do -    // anything. If foo is a function, `*foo`, `**foo` or `*****foo` -    // are all equivalent to just `foo`. -    Node *node = cast(rest, tok->next); -    add_type(node); -    if (node->ty->kind == TY_FUNC) -      return node; -    return new_unary(ND_DEREF, node, tok); -  } - -  if (equal(tok, "!")) -    return new_unary(ND_NOT, cast(rest, tok->next), tok); - -  if (equal(tok, "~")) -    return new_unary(ND_BITNOT, cast(rest, tok->next), tok); - -  // Read ++i as i+=1 -  if (equal(tok, "++")) -    return to_assign(new_add(unary(rest, tok->next), new_num(1, tok), tok)); - -  // Read --i as i-=1 -  if (equal(tok, "--")) -    return to_assign(new_sub(unary(rest, tok->next), new_num(1, tok), tok)); - -  // [GNU] labels-as-values -  if (equal(tok, "&&")) { -    Node *node = new_node(ND_LABEL_VAL, tok); -    node->label = get_ident(tok->next); -    node->goto_next = gotos; -    gotos = node; -    *rest = tok->next->next; -    return node; -  } - -  return postfix(rest, tok); -} - -// struct-members = (declspec declarator (","  declarator)* ";")* -static void struct_members(Token **rest, Token *tok, Type *ty) { -  Member head = {}; -  Member *cur = &head; -  int idx = 0; - -  while (!equal(tok, "}")) { -    VarAttr attr = {}; -    Type *basety = declspec(&tok, tok, &attr); -    bool first = true; - -    // Anonymous struct member -    if ((basety->kind == TY_STRUCT || basety->kind == TY_UNION) && -        consume(&tok, tok, ";")) { -      Member *mem = calloc(1, sizeof(Member)); -      mem->ty = basety; -      mem->idx = idx++; -      mem->align = attr.align ? attr.align : mem->ty->align; -      cur = cur->next = mem; -      continue; -    } - -    // Regular struct members -    while (!consume(&tok, tok, ";")) { -      if (!first) -        tok = skip(tok, ","); -      first = false; - -      Member *mem = calloc(1, sizeof(Member)); -      mem->ty = declarator(&tok, tok, basety); -      mem->name = mem->ty->name; -      mem->idx = idx++; -      mem->align = attr.align ? attr.align : mem->ty->align; - -      if (consume(&tok, tok, ":")) { -        mem->is_bitfield = true; -        mem->bit_width = const_expr(&tok, tok); -      } - -      cur = cur->next = mem; -    } -  } - -  // If the last element is an array of incomplete type, it's -  // called a "flexible array member". It should behave as if -  // if were a zero-sized array. -  if (cur != &head && cur->ty->kind == TY_ARRAY && cur->ty->array_len < 0) { -    cur->ty = array_of(cur->ty->base, 0); -    ty->is_flexible = true; -  } - -  *rest = tok->next; -  ty->members = head.next; -} - -// attribute = ("__attribute__" "(" "(" "packed" ")" ")")* -static Token *attribute_list(Token *tok, Type *ty) { -  while (consume(&tok, tok, "__attribute__")) { -    tok = skip(tok, "("); -    tok = skip(tok, "("); - -    bool first = true; - -    while (!consume(&tok, tok, ")")) { -      if (!first) -        tok = skip(tok, ","); -      first = false; - -      if (consume(&tok, tok, "packed")) { -        ty->is_packed = true; -        continue; -      } - -      if (consume(&tok, tok, "aligned")) { -        tok = skip(tok, "("); -        ty->align = const_expr(&tok, tok); -        tok = skip(tok, ")"); -        continue; -      } - -      error_tok(tok, "unknown attribute"); -    } - -    tok = skip(tok, ")"); -  } - -  return tok; -} - -// struct-union-decl = attribute? ident? ("{" struct-members)? -static Type *struct_union_decl(Token **rest, Token *tok) { -  Type *ty = struct_type(); -  tok = attribute_list(tok, ty); - -  // Read a tag. -  Token *tag = NULL; -  if (tok->kind == TK_IDENT) { -    tag = tok; -    tok = tok->next; -  } - -  if (tag && !equal(tok, "{")) { -    *rest = tok; - -    Type *ty2 = find_tag(tag); -    if (ty2) -      return ty2; - -    ty->size = -1; -    push_tag_scope(tag, ty); -    return ty; -  } - -  tok = skip(tok, "{"); - -  // Construct a struct object. -  struct_members(&tok, tok, ty); -  *rest = attribute_list(tok, ty); - -  if (tag) { -    // If this is a redefinition, overwrite a previous type. -    // Otherwise, register the struct type. -    Type *ty2 = hashmap_get2(&scope->tags, tag->loc, tag->len); -    if (ty2) { -      *ty2 = *ty; -      return ty2; -    } - -    push_tag_scope(tag, ty); -  } - -  return ty; -} - -// struct-decl = struct-union-decl -static Type *struct_decl(Token **rest, Token *tok) { -  Type *ty = struct_union_decl(rest, tok); -  ty->kind = TY_STRUCT; - -  if (ty->size < 0) -    return ty; - -  // Assign offsets within the struct to members. -  int bits = 0; - -  for (Member *mem = ty->members; mem; mem = mem->next) { -    if (mem->is_bitfield && mem->bit_width == 0) { -      // Zero-width anonymous bitfield has a special meaning. -      // It affects only alignment. -      bits = align_to(bits, mem->ty->size * 8); -    } else if (mem->is_bitfield) { -      int sz = mem->ty->size; -      if (bits / (sz * 8) != (bits + mem->bit_width - 1) / (sz * 8)) -        bits = align_to(bits, sz * 8); - -      mem->offset = align_down(bits / 8, sz); -      mem->bit_offset = bits % (sz * 8); -      bits += mem->bit_width; -    } else { -      if (!ty->is_packed) -        bits = align_to(bits, mem->align * 8); -      mem->offset = bits / 8; -      bits += mem->ty->size * 8; -    } - -    if (!ty->is_packed && ty->align < mem->align) -      ty->align = mem->align; -  } - -  ty->size = align_to(bits, ty->align * 8) / 8; -  return ty; -} - -// union-decl = struct-union-decl -static Type *union_decl(Token **rest, Token *tok) { -  Type *ty = struct_union_decl(rest, tok); -  ty->kind = TY_UNION; - -  if (ty->size < 0) -    return ty; - -  // If union, we don't have to assign offsets because they -  // are already initialized to zero. We need to compute the -  // alignment and the size though. -  for (Member *mem = ty->members; mem; mem = mem->next) { -    if (ty->align < mem->align) -      ty->align = mem->align; -    if (ty->size < mem->ty->size) -      ty->size = mem->ty->size; -  } -  ty->size = align_to(ty->size, ty->align); -  return ty; -} - -// Find a struct member by name. -static Member *get_struct_member(Type *ty, Token *tok) { -  for (Member *mem = ty->members; mem; mem = mem->next) { -    // Anonymous struct member -    if ((mem->ty->kind == TY_STRUCT || mem->ty->kind == TY_UNION) && -        !mem->name) { -      if (get_struct_member(mem->ty, tok)) -        return mem; -      continue; -    } - -    // Regular struct member -    if (mem->name->len == tok->len && -        !strncmp(mem->name->loc, tok->loc, tok->len)) -      return mem; -  } -  return NULL; -} - -// Create a node representing a struct member access, such as foo.bar -// where foo is a struct and bar is a member name. -// -// C has a feature called "anonymous struct" which allows a struct to -// have another unnamed struct as a member like this: -// -//   struct { struct { int a; }; int b; } x; -// -// The members of an anonymous struct belong to the outer struct's -// member namespace. Therefore, in the above example, you can access -// member "a" of the anonymous struct as "x.a". -// -// This function takes care of anonymous structs. -static Node *struct_ref(Node *node, Token *tok) { -  add_type(node); -  if (node->ty->kind != TY_STRUCT && node->ty->kind != TY_UNION) -    error_tok(node->tok, "not a struct nor a union"); - -  Type *ty = node->ty; - -  for (;;) { -    Member *mem = get_struct_member(ty, tok); -    if (!mem) -      error_tok(tok, "no such member"); -    node = new_unary(ND_MEMBER, node, tok); -    node->member = mem; -    if (mem->name) -      break; -    ty = mem->ty; -  } -  return node; -} - -// Convert A++ to `(typeof A)((A += 1) - 1)` -static Node *new_inc_dec(Node *node, Token *tok, int addend) { -  add_type(node); -  return new_cast(new_add(to_assign(new_add(node, new_num(addend, tok), tok)), -                          new_num(-addend, tok), tok), -                  node->ty); -} - -// postfix = "(" type-name ")" "{" initializer-list "}" -//         = ident "(" func-args ")" postfix-tail* -//         | primary postfix-tail* -// -// postfix-tail = "[" expr "]" -//              | "(" func-args ")" -//              | "." ident -//              | "->" ident -//              | "++" -//              | "--" -static Node *postfix(Token **rest, Token *tok) { -  if (equal(tok, "(") && is_typename(tok->next)) { -    // Compound literal -    Token *start = tok; -    Type *ty = typename(&tok, tok->next); -    tok = skip(tok, ")"); - -    if (scope->next == NULL) { -      Obj *var = new_anon_gvar(ty); -      gvar_initializer(rest, tok, var); -      return new_var_node(var, start); -    } - -    Obj *var = new_lvar("", ty); -    Node *lhs = lvar_initializer(rest, tok, var); -    Node *rhs = new_var_node(var, tok); -    return new_binary(ND_COMMA, lhs, rhs, start); -  } - -  Node *node = primary(&tok, tok); - -  for (;;) { -    if (equal(tok, "(")) { -      node = funcall(&tok, tok->next, node); -      continue; -    } - -    if (equal(tok, "[")) { -      // x[y] is short for *(x+y) -      Token *start = tok; -      Node *idx = expr(&tok, tok->next); -      tok = skip(tok, "]"); -      node = new_unary(ND_DEREF, new_add(node, idx, start), start); -      continue; -    } - -    if (equal(tok, ".")) { -      node = struct_ref(node, tok->next); -      tok = tok->next->next; -      continue; -    } - -    if (equal(tok, "->")) { -      // x->y is short for (*x).y -      node = new_unary(ND_DEREF, node, tok); -      node = struct_ref(node, tok->next); -      tok = tok->next->next; -      continue; -    } - -    if (equal(tok, "++")) { -      node = new_inc_dec(node, tok, 1); -      tok = tok->next; -      continue; -    } - -    if (equal(tok, "--")) { -      node = new_inc_dec(node, tok, -1); -      tok = tok->next; -      continue; -    } - -    *rest = tok; -    return node; -  } -} - -// funcall = (assign ("," assign)*)? ")" -static Node *funcall(Token **rest, Token *tok, Node *fn) { -  add_type(fn); - -  if (fn->ty->kind != TY_FUNC && -      (fn->ty->kind != TY_PTR || fn->ty->base->kind != TY_FUNC)) -    error_tok(fn->tok, "not a function"); - -  Type *ty = (fn->ty->kind == TY_FUNC) ? fn->ty : fn->ty->base; -  Type *param_ty = ty->params; - -  Node head = {}; -  Node *cur = &head; - -  while (!equal(tok, ")")) { -    if (cur != &head) -      tok = skip(tok, ","); - -    Node *arg = assign(&tok, tok); -    add_type(arg); - -    if (!param_ty && !ty->is_variadic) -      error_tok(tok, "too many arguments"); - -    if (param_ty) { -      if (param_ty->kind != TY_STRUCT && param_ty->kind != TY_UNION) -        arg = new_cast(arg, param_ty); -      param_ty = param_ty->next; -    } else if (arg->ty->kind == TY_FLOAT) { -      // If parameter type is omitted (e.g. in "..."), float -      // arguments are promoted to double. -      arg = new_cast(arg, ty_double); -    } - -    cur = cur->next = arg; -  } - -  if (param_ty) -    error_tok(tok, "too few arguments"); - -  *rest = skip(tok, ")"); - -  Node *node = new_unary(ND_FUNCALL, fn, tok); -  node->func_ty = ty; -  node->ty = ty->return_ty; -  node->args = head.next; - -  // If a function returns a struct, it is caller's responsibility -  // to allocate a space for the return value. -  if (node->ty->kind == TY_STRUCT || node->ty->kind == TY_UNION) -    node->ret_buffer = new_lvar("", node->ty); -  return node; -} - -// generic-selection = "(" assign "," generic-assoc ("," generic-assoc)* ")" -// -// generic-assoc = type-name ":" assign -//               | "default" ":" assign -static Node *generic_selection(Token **rest, Token *tok) { -  Token *start = tok; -  tok = skip(tok, "("); - -  Node *ctrl = assign(&tok, tok); -  add_type(ctrl); - -  Type *t1 = ctrl->ty; -  if (t1->kind == TY_FUNC) -    t1 = pointer_to(t1); -  else if (t1->kind == TY_ARRAY) -    t1 = pointer_to(t1->base); - -  Node *ret = NULL; - -  while (!consume(rest, tok, ")")) { -    tok = skip(tok, ","); - -    if (equal(tok, "default")) { -      tok = skip(tok->next, ":"); -      Node *node = assign(&tok, tok); -      if (!ret) -        ret = node; -      continue; -    } - -    Type *t2 = typename(&tok, tok); -    tok = skip(tok, ":"); -    Node *node = assign(&tok, tok); -    if (is_compatible(t1, t2)) -      ret = node; -  } - -  if (!ret) -    error_tok(start, "controlling expression type not compatible with" -              " any generic association type"); -  return ret; -} - -// primary = "(" "{" stmt+ "}" ")" -//         | "(" expr ")" -//         | "sizeof" "(" type-name ")" -//         | "sizeof" unary -//         | "_Alignof" "(" type-name ")" -//         | "_Alignof" unary -//         | "_Generic" generic-selection -//         | "__builtin_types_compatible_p" "(" type-name, type-name, ")" -//         | "__builtin_reg_class" "(" type-name ")" -//         | ident -//         | str -//         | num -static Node *primary(Token **rest, Token *tok) { -  Token *start = tok; - -  if (equal(tok, "(") && equal(tok->next, "{")) { -    // This is a GNU statement expresssion. -    Node *node = new_node(ND_STMT_EXPR, tok); -    node->body = compound_stmt(&tok, tok->next->next)->body; -    *rest = skip(tok, ")"); -    return node; -  } - -  if (equal(tok, "(")) { -    Node *node = expr(&tok, tok->next); -    *rest = skip(tok, ")"); -    return node; -  } - -  if (equal(tok, "sizeof") && equal(tok->next, "(") && is_typename(tok->next->next)) { -    Type *ty = typename(&tok, tok->next->next); -    *rest = skip(tok, ")"); - -    if (ty->kind == TY_VLA) { -      if (ty->vla_size) -        return new_var_node(ty->vla_size, tok); - -      Node *lhs = compute_vla_size(ty, tok); -      Node *rhs = new_var_node(ty->vla_size, tok); -      return new_binary(ND_COMMA, lhs, rhs, tok); -    } - -    return new_ulong(ty->size, start); -  } - -  if (equal(tok, "sizeof")) { -    Node *node = unary(rest, tok->next); -    add_type(node); -    if (node->ty->kind == TY_VLA) -      return new_var_node(node->ty->vla_size, tok); -    return new_ulong(node->ty->size, tok); -  } - -  if (equal(tok, "_Alignof") && equal(tok->next, "(") && is_typename(tok->next->next)) { -    Type *ty = typename(&tok, tok->next->next); -    *rest = skip(tok, ")"); -    return new_ulong(ty->align, tok); -  } - -  if (equal(tok, "_Alignof")) { -    Node *node = unary(rest, tok->next); -    add_type(node); -    return new_ulong(node->ty->align, tok); -  } - -  if (equal(tok, "_Generic")) -    return generic_selection(rest, tok->next); - -  if (equal(tok, "__builtin_types_compatible_p")) { -    tok = skip(tok->next, "("); -    Type *t1 = typename(&tok, tok); -    tok = skip(tok, ","); -    Type *t2 = typename(&tok, tok); -    *rest = skip(tok, ")"); -    return new_num(is_compatible(t1, t2), start); -  } - -  if (equal(tok, "__builtin_reg_class")) { -    tok = skip(tok->next, "("); -    Type *ty = typename(&tok, tok); -    *rest = skip(tok, ")"); - -    if (is_integer(ty) || ty->kind == TY_PTR) -      return new_num(0, start); -    if (is_flonum(ty)) -      return new_num(1, start); -    return new_num(2, start); -  } - -  if (equal(tok, "__builtin_compare_and_swap")) { -    Node *node = new_node(ND_CAS, tok); -    tok = skip(tok->next, "("); -    node->cas_addr = assign(&tok, tok); -    tok = skip(tok, ","); -    node->cas_old = assign(&tok, tok); -    tok = skip(tok, ","); -    node->cas_new = assign(&tok, tok); -    *rest = skip(tok, ")"); -    return node; -  } - -  if (equal(tok, "__builtin_atomic_exchange")) { -    Node *node = new_node(ND_EXCH, tok); -    tok = skip(tok->next, "("); -    node->lhs = assign(&tok, tok); -    tok = skip(tok, ","); -    node->rhs = assign(&tok, tok); -    *rest = skip(tok, ")"); -    return node; -  } - -  if (tok->kind == TK_IDENT) { -    // Variable or enum constant -    VarScope *sc = find_var(tok); -    *rest = tok->next; - -    // For "static inline" function -    if (sc && sc->var && sc->var->is_function) { -      if (current_fn) -        strarray_push(¤t_fn->refs, sc->var->name); -      else -        sc->var->is_root = true; -    } - -    if (sc) { -      if (sc->var) -        return new_var_node(sc->var, tok); -      if (sc->enum_ty) -        return new_num(sc->enum_val, tok); -    } - -    if (equal(tok->next, "(")) -      error_tok(tok, "implicit declaration of a function"); -    error_tok(tok, "undefined variable"); -  } - -  if (tok->kind == TK_STR) { -    Obj *var = new_string_literal(tok->str, tok->ty); -    *rest = tok->next; -    return new_var_node(var, tok); -  } - -  if (tok->kind == TK_NUM) { -    Node *node; -    if (is_flonum(tok->ty)) { -      node = new_node(ND_NUM, tok); -      node->fval = tok->fval; -    } else { -      node = new_num(tok->val, tok); -    } - -    node->ty = tok->ty; -    *rest = tok->next; -    return node; -  } - -  error_tok(tok, "expected an expression"); -} - -static Token *parse_typedef(Token *tok, Type *basety) { -  bool first = true; - -  while (!consume(&tok, tok, ";")) { -    if (!first) -      tok = skip(tok, ","); -    first = false; - -    Type *ty = declarator(&tok, tok, basety); -    if (!ty->name) -      error_tok(ty->name_pos, "typedef name omitted"); -    push_scope(get_ident(ty->name))->type_def = ty; -  } -  return tok; -} - -static void create_param_lvars(Type *param) { -  if (param) { -    create_param_lvars(param->next); -    if (!param->name) -      error_tok(param->name_pos, "parameter name omitted"); -    new_lvar(get_ident(param->name), param); -  } -} - -// This function matches gotos or labels-as-values with labels. -// -// We cannot resolve gotos as we parse a function because gotos -// can refer a label that appears later in the function. -// So, we need to do this after we parse the entire function. -static void resolve_goto_labels(void) { -  for (Node *x = gotos; x; x = x->goto_next) { -    for (Node *y = labels; y; y = y->goto_next) { -      if (!strcmp(x->label, y->label)) { -        x->unique_label = y->unique_label; -        break; -      } -    } - -    if (x->unique_label == NULL) -      error_tok(x->tok->next, "use of undeclared label"); -  } - -  gotos = labels = NULL; -} - -static Obj *find_func(char *name) { -  Scope *sc = scope; -  while (sc->next) -    sc = sc->next; - -  VarScope *sc2 = hashmap_get(&sc->vars, name); -  if (sc2 && sc2->var && sc2->var->is_function) -    return sc2->var; -  return NULL; -} - -static void mark_live(Obj *var) { -  if (!var->is_function || var->is_live) -    return; -  var->is_live = true; - -  for (int i = 0; i < var->refs.len; i++) { -    Obj *fn = find_func(var->refs.data[i]); -    if (fn) -      mark_live(fn); -  } -} - -static Token *function(Token *tok, Type *basety, VarAttr *attr) { -  Type *ty = declarator(&tok, tok, basety); -  if (!ty->name) -    error_tok(ty->name_pos, "function name omitted"); -  char *name_str = get_ident(ty->name); - -  Obj *fn = find_func(name_str); -  if (fn) { -    // Redeclaration -    if (!fn->is_function) -      error_tok(tok, "redeclared as a different kind of symbol"); -    if (fn->is_definition && equal(tok, "{")) -      error_tok(tok, "redefinition of %s", name_str); -    if (!fn->is_static && attr->is_static) -      error_tok(tok, "static declaration follows a non-static declaration"); -    fn->is_definition = fn->is_definition || equal(tok, "{"); -  } else { -    fn = new_gvar(name_str, ty); -    fn->is_function = true; -    fn->is_definition = equal(tok, "{"); -    fn->is_static = attr->is_static || (attr->is_inline && !attr->is_extern); -    fn->is_inline = attr->is_inline; -  } - -  fn->is_root = !(fn->is_static && fn->is_inline); - -  if (consume(&tok, tok, ";")) -    return tok; - -  current_fn = fn; -  locals = NULL; -  enter_scope(); -  create_param_lvars(ty->params); - -  // A buffer for a struct/union return value is passed -  // as the hidden first parameter. -  Type *rty = ty->return_ty; -  if ((rty->kind == TY_STRUCT || rty->kind == TY_UNION) && rty->size > 16) -    new_lvar("", pointer_to(rty)); - -  fn->params = locals; - -  if (ty->is_variadic) -    fn->va_area = new_lvar("__va_area__", array_of(ty_char, 136)); -  fn->alloca_bottom = new_lvar("__alloca_size__", pointer_to(ty_char)); - -  tok = skip(tok, "{"); - -  // [https://www.sigbus.info/n1570#6.4.2.2p1] "__func__" is -  // automatically defined as a local variable containing the -  // current function name. -  push_scope("__func__")->var = -    new_string_literal(fn->name, array_of(ty_char, strlen(fn->name) + 1)); - -  // [GNU] __FUNCTION__ is yet another name of __func__. -  push_scope("__FUNCTION__")->var = -    new_string_literal(fn->name, array_of(ty_char, strlen(fn->name) + 1)); - -  fn->body = compound_stmt(&tok, tok); -  fn->locals = locals; -  leave_scope(); -  resolve_goto_labels(); -  return tok; -} - -static Token *global_variable(Token *tok, Type *basety, VarAttr *attr) { -  bool first = true; - -  while (!consume(&tok, tok, ";")) { -    if (!first) -      tok = skip(tok, ","); -    first = false; - -    Type *ty = declarator(&tok, tok, basety); -    if (!ty->name) -      error_tok(ty->name_pos, "variable name omitted"); - -    Obj *var = new_gvar(get_ident(ty->name), ty); -    var->is_definition = !attr->is_extern; -    var->is_static = attr->is_static; -    var->is_tls = attr->is_tls; -    if (attr->align) -      var->align = attr->align; - -    if (equal(tok, "=")) -      gvar_initializer(&tok, tok->next, var); -    else if (!attr->is_extern && !attr->is_tls) -      var->is_tentative = true; -  } -  return tok; -} - -// Lookahead tokens and returns true if a given token is a start -// of a function definition or declaration. -static bool is_function(Token *tok) { -  if (equal(tok, ";")) -    return false; - -  Type dummy = {}; -  Type *ty = declarator(&tok, tok, &dummy); -  return ty->kind == TY_FUNC; -} - -// Remove redundant tentative definitions. -static void scan_globals(void) { -  Obj head; -  Obj *cur = &head; - -  for (Obj *var = globals; var; var = var->next) { -    if (!var->is_tentative) { -      cur = cur->next = var; -      continue; -    } - -    // Find another definition of the same identifier. -    Obj *var2 = globals; -    for (; var2; var2 = var2->next) -      if (var != var2 && var2->is_definition && !strcmp(var->name, var2->name)) -        break; - -    // If there's another definition, the tentative definition -    // is redundant -    if (!var2) -      cur = cur->next = var; -  } - -  cur->next = NULL; -  globals = head.next; -} - -static void declare_builtin_functions(void) { -  Type *ty = func_type(pointer_to(ty_void)); -  ty->params = copy_type(ty_int); -  builtin_alloca = new_gvar("alloca", ty); -  builtin_alloca->is_definition = false; -} - -// program = (typedef | function-definition | global-variable)* -Obj *parse(Token *tok) { -  declare_builtin_functions(); -  globals = NULL; - -  while (tok->kind != TK_EOF) { -    VarAttr attr = {}; -    Type *basety = declspec(&tok, tok, &attr); - -    // Typedef -    if (attr.is_typedef) { -      tok = parse_typedef(tok, basety); -      continue; -    } - -    // Function -    if (is_function(tok)) { -      tok = function(tok, basety, &attr); -      continue; -    } - -    // Global variable -    tok = global_variable(tok, basety, &attr); -  } - -  for (Obj *var = globals; var; var = var->next) -    if (var->is_root) -      mark_live(var); - -  // Remove redundant tentative definitions. -  scan_globals(); -  return globals; -} diff --git a/src/3p/chibicc/preprocess.c b/src/3p/chibicc/preprocess.c deleted file mode 100644 index cd8d1d8..0000000 --- a/src/3p/chibicc/preprocess.c +++ /dev/null @@ -1,1208 +0,0 @@ -// This file implements the C preprocessor. -// -// The preprocessor takes a list of tokens as an input and returns a -// new list of tokens as an output. -// -// The preprocessing language is designed in such a way that that's -// guaranteed to stop even if there is a recursive macro. -// Informally speaking, a macro is applied only once for each token. -// That is, if a macro token T appears in a result of direct or -// indirect macro expansion of T, T won't be expanded any further. -// For example, if T is defined as U, and U is defined as T, then -// token T is expanded to U and then to T and the macro expansion -// stops at that point. -// -// To achieve the above behavior, we attach for each token a set of -// macro names from which the token is expanded. The set is called -// "hideset". Hideset is initially empty, and every time we expand a -// macro, the macro name is added to the resulting tokens' hidesets. -// -// The above macro expansion algorithm is explained in this document -// written by Dave Prossor, which is used as a basis for the -// standard's wording: -// https://github.com/rui314/chibicc/wiki/cpp.algo.pdf - -#include "chibicc.h" - -typedef struct MacroParam MacroParam; -struct MacroParam { -  MacroParam *next; -  char *name; -}; - -typedef struct MacroArg MacroArg; -struct MacroArg { -  MacroArg *next; -  char *name; -  bool is_va_args; -  Token *tok; -}; - -typedef Token *macro_handler_fn(Token *); - -typedef struct Macro Macro; -struct Macro { -  char *name; -  bool is_objlike; // Object-like or function-like -  MacroParam *params; -  char *va_args_name; -  Token *body; -  macro_handler_fn *handler; -}; - -// `#if` can be nested, so we use a stack to manage nested `#if`s. -typedef struct CondIncl CondIncl; -struct CondIncl { -  CondIncl *next; -  enum { IN_THEN, IN_ELIF, IN_ELSE } ctx; -  Token *tok; -  bool included; -}; - -typedef struct Hideset Hideset; -struct Hideset { -  Hideset *next; -  char *name; -}; - -static HashMap macros; -static CondIncl *cond_incl; -static HashMap pragma_once; -static int include_next_idx; - -static Token *preprocess2(Token *tok); -static Macro *find_macro(Token *tok); - -static bool is_hash(Token *tok) { -  return tok->at_bol && equal(tok, "#"); -} - -// Some preprocessor directives such as #include allow extraneous -// tokens before newline. This function skips such tokens. -static Token *skip_line(Token *tok) { -  if (tok->at_bol) -    return tok; -  warn_tok(tok, "extra token"); -  while (!tok->at_bol) -    tok = tok->next; -  return tok; -} - -static Token *copy_token(Token *tok) { -  Token *t = calloc(1, sizeof(Token)); -  *t = *tok; -  t->next = NULL; -  return t; -} - -static Token *new_eof(Token *tok) { -  Token *t = copy_token(tok); -  t->kind = TK_EOF; -  t->len = 0; -  return t; -} - -static Hideset *new_hideset(char *name) { -  Hideset *hs = calloc(1, sizeof(Hideset)); -  hs->name = name; -  return hs; -} - -static Hideset *hideset_union(Hideset *hs1, Hideset *hs2) { -  Hideset head = {}; -  Hideset *cur = &head; - -  for (; hs1; hs1 = hs1->next) -    cur = cur->next = new_hideset(hs1->name); -  cur->next = hs2; -  return head.next; -} - -static bool hideset_contains(Hideset *hs, char *s, int len) { -  for (; hs; hs = hs->next) -    if (strlen(hs->name) == len && !strncmp(hs->name, s, len)) -      return true; -  return false; -} - -static Hideset *hideset_intersection(Hideset *hs1, Hideset *hs2) { -  Hideset head = {}; -  Hideset *cur = &head; - -  for (; hs1; hs1 = hs1->next) -    if (hideset_contains(hs2, hs1->name, strlen(hs1->name))) -      cur = cur->next = new_hideset(hs1->name); -  return head.next; -} - -static Token *add_hideset(Token *tok, Hideset *hs) { -  Token head = {}; -  Token *cur = &head; - -  for (; tok; tok = tok->next) { -    Token *t = copy_token(tok); -    t->hideset = hideset_union(t->hideset, hs); -    cur = cur->next = t; -  } -  return head.next; -} - -// Append tok2 to the end of tok1. -static Token *append(Token *tok1, Token *tok2) { -  if (tok1->kind == TK_EOF) -    return tok2; - -  Token head = {}; -  Token *cur = &head; - -  for (; tok1->kind != TK_EOF; tok1 = tok1->next) -    cur = cur->next = copy_token(tok1); -  cur->next = tok2; -  return head.next; -} - -static Token *skip_cond_incl2(Token *tok) { -  while (tok->kind != TK_EOF) { -    if (is_hash(tok) && -        (equal(tok->next, "if") || equal(tok->next, "ifdef") || -         equal(tok->next, "ifndef"))) { -      tok = skip_cond_incl2(tok->next->next); -      continue; -    } -    if (is_hash(tok) && equal(tok->next, "endif")) -      return tok->next->next; -    tok = tok->next; -  } -  return tok; -} - -// Skip until next `#else`, `#elif` or `#endif`. -// Nested `#if` and `#endif` are skipped. -static Token *skip_cond_incl(Token *tok) { -  while (tok->kind != TK_EOF) { -    if (is_hash(tok) && -        (equal(tok->next, "if") || equal(tok->next, "ifdef") || -         equal(tok->next, "ifndef"))) { -      tok = skip_cond_incl2(tok->next->next); -      continue; -    } - -    if (is_hash(tok) && -        (equal(tok->next, "elif") || equal(tok->next, "else") || -         equal(tok->next, "endif"))) -      break; -    tok = tok->next; -  } -  return tok; -} - -// Double-quote a given string and returns it. -static char *quote_string(char *str) { -  int bufsize = 3; -  for (int i = 0; str[i]; i++) { -    if (str[i] == '\\' || str[i] == '"') -      bufsize++; -    bufsize++; -  } - -  char *buf = calloc(1, bufsize); -  char *p = buf; -  *p++ = '"'; -  for (int i = 0; str[i]; i++) { -    if (str[i] == '\\' || str[i] == '"') -      *p++ = '\\'; -    *p++ = str[i]; -  } -  *p++ = '"'; -  *p++ = '\0'; -  return buf; -} - -static Token *new_str_token(char *str, Token *tmpl) { -  char *buf = quote_string(str); -  return tokenize(new_file(tmpl->file->name, tmpl->file->file_no, buf)); -} - -// Copy all tokens until the next newline, terminate them with -// an EOF token and then returns them. This function is used to -// create a new list of tokens for `#if` arguments. -static Token *copy_line(Token **rest, Token *tok) { -  Token head = {}; -  Token *cur = &head; - -  for (; !tok->at_bol; tok = tok->next) -    cur = cur->next = copy_token(tok); - -  cur->next = new_eof(tok); -  *rest = tok; -  return head.next; -} - -static Token *new_num_token(int val, Token *tmpl) { -  char *buf = format("%d\n", val); -  return tokenize(new_file(tmpl->file->name, tmpl->file->file_no, buf)); -} - -static Token *read_const_expr(Token **rest, Token *tok) { -  tok = copy_line(rest, tok); - -  Token head = {}; -  Token *cur = &head; - -  while (tok->kind != TK_EOF) { -    // "defined(foo)" or "defined foo" becomes "1" if macro "foo" -    // is defined. Otherwise "0". -    if (equal(tok, "defined")) { -      Token *start = tok; -      bool has_paren = consume(&tok, tok->next, "("); - -      if (tok->kind != TK_IDENT) -        error_tok(start, "macro name must be an identifier"); -      Macro *m = find_macro(tok); -      tok = tok->next; - -      if (has_paren) -        tok = skip(tok, ")"); - -      cur = cur->next = new_num_token(m ? 1 : 0, start); -      continue; -    } - -    cur = cur->next = tok; -    tok = tok->next; -  } - -  cur->next = tok; -  return head.next; -} - -// Read and evaluate a constant expression. -static long eval_const_expr(Token **rest, Token *tok) { -  Token *start = tok; -  Token *expr = read_const_expr(rest, tok->next); -  expr = preprocess2(expr); - -  if (expr->kind == TK_EOF) -    error_tok(start, "no expression"); - -  // [https://www.sigbus.info/n1570#6.10.1p4] The standard requires -  // we replace remaining non-macro identifiers with "0" before -  // evaluating a constant expression. For example, `#if foo` is -  // equivalent to `#if 0` if foo is not defined. -  for (Token *t = expr; t->kind != TK_EOF; t = t->next) { -    if (t->kind == TK_IDENT) { -      Token *next = t->next; -      *t = *new_num_token(0, t); -      t->next = next; -    } -  } - -  // Convert pp-numbers to regular numbers -  convert_pp_tokens(expr); - -  Token *rest2; -  long val = const_expr(&rest2, expr); -  if (rest2->kind != TK_EOF) -    error_tok(rest2, "extra token"); -  return val; -} - -static CondIncl *push_cond_incl(Token *tok, bool included) { -  CondIncl *ci = calloc(1, sizeof(CondIncl)); -  ci->next = cond_incl; -  ci->ctx = IN_THEN; -  ci->tok = tok; -  ci->included = included; -  cond_incl = ci; -  return ci; -} - -static Macro *find_macro(Token *tok) { -  if (tok->kind != TK_IDENT) -    return NULL; -  return hashmap_get2(¯os, tok->loc, tok->len); -} - -static Macro *add_macro(char *name, bool is_objlike, Token *body) { -  Macro *m = calloc(1, sizeof(Macro)); -  m->name = name; -  m->is_objlike = is_objlike; -  m->body = body; -  hashmap_put(¯os, name, m); -  return m; -} - -static MacroParam *read_macro_params(Token **rest, Token *tok, char **va_args_name) { -  MacroParam head = {}; -  MacroParam *cur = &head; - -  while (!equal(tok, ")")) { -    if (cur != &head) -      tok = skip(tok, ","); - -    if (equal(tok, "...")) { -      *va_args_name = "__VA_ARGS__"; -      *rest = skip(tok->next, ")"); -      return head.next; -    } - -    if (tok->kind != TK_IDENT) -      error_tok(tok, "expected an identifier"); - -    if (equal(tok->next, "...")) { -      *va_args_name = strndup(tok->loc, tok->len); -      *rest = skip(tok->next->next, ")"); -      return head.next; -    } - -    MacroParam *m = calloc(1, sizeof(MacroParam)); -    m->name = strndup(tok->loc, tok->len); -    cur = cur->next = m; -    tok = tok->next; -  } - -  *rest = tok->next; -  return head.next; -} - -static void read_macro_definition(Token **rest, Token *tok) { -  if (tok->kind != TK_IDENT) -    error_tok(tok, "macro name must be an identifier"); -  char *name = strndup(tok->loc, tok->len); -  tok = tok->next; - -  if (!tok->has_space && equal(tok, "(")) { -    // Function-like macro -    char *va_args_name = NULL; -    MacroParam *params = read_macro_params(&tok, tok->next, &va_args_name); - -    Macro *m = add_macro(name, false, copy_line(rest, tok)); -    m->params = params; -    m->va_args_name = va_args_name; -  } else { -    // Object-like macro -    add_macro(name, true, copy_line(rest, tok)); -  } -} - -static MacroArg *read_macro_arg_one(Token **rest, Token *tok, bool read_rest) { -  Token head = {}; -  Token *cur = &head; -  int level = 0; - -  for (;;) { -    if (level == 0 && equal(tok, ")")) -      break; -    if (level == 0 && !read_rest && equal(tok, ",")) -      break; - -    if (tok->kind == TK_EOF) -      error_tok(tok, "premature end of input"); - -    if (equal(tok, "(")) -      level++; -    else if (equal(tok, ")")) -      level--; - -    cur = cur->next = copy_token(tok); -    tok = tok->next; -  } - -  cur->next = new_eof(tok); - -  MacroArg *arg = calloc(1, sizeof(MacroArg)); -  arg->tok = head.next; -  *rest = tok; -  return arg; -} - -static MacroArg * -read_macro_args(Token **rest, Token *tok, MacroParam *params, char *va_args_name) { -  Token *start = tok; -  tok = tok->next->next; - -  MacroArg head = {}; -  MacroArg *cur = &head; - -  MacroParam *pp = params; -  for (; pp; pp = pp->next) { -    if (cur != &head) -      tok = skip(tok, ","); -    cur = cur->next = read_macro_arg_one(&tok, tok, false); -    cur->name = pp->name; -  } - -  if (va_args_name) { -    MacroArg *arg; -    if (equal(tok, ")")) { -      arg = calloc(1, sizeof(MacroArg)); -      arg->tok = new_eof(tok); -    } else { -      if (pp != params) -        tok = skip(tok, ","); -      arg = read_macro_arg_one(&tok, tok, true); -    } -    arg->name = va_args_name;; -    arg->is_va_args = true; -    cur = cur->next = arg; -  } else if (pp) { -    error_tok(start, "too many arguments"); -  } - -  skip(tok, ")"); -  *rest = tok; -  return head.next; -} - -static MacroArg *find_arg(MacroArg *args, Token *tok) { -  for (MacroArg *ap = args; ap; ap = ap->next) -    if (tok->len == strlen(ap->name) && !strncmp(tok->loc, ap->name, tok->len)) -      return ap; -  return NULL; -} - -// Concatenates all tokens in `tok` and returns a new string. -static char *join_tokens(Token *tok, Token *end) { -  // Compute the length of the resulting token. -  int len = 1; -  for (Token *t = tok; t != end && t->kind != TK_EOF; t = t->next) { -    if (t != tok && t->has_space) -      len++; -    len += t->len; -  } - -  char *buf = calloc(1, len); - -  // Copy token texts. -  int pos = 0; -  for (Token *t = tok; t != end && t->kind != TK_EOF; t = t->next) { -    if (t != tok && t->has_space) -      buf[pos++] = ' '; -    strncpy(buf + pos, t->loc, t->len); -    pos += t->len; -  } -  buf[pos] = '\0'; -  return buf; -} - -// Concatenates all tokens in `arg` and returns a new string token. -// This function is used for the stringizing operator (#). -static Token *stringize(Token *hash, Token *arg) { -  // Create a new string token. We need to set some value to its -  // source location for error reporting function, so we use a macro -  // name token as a template. -  char *s = join_tokens(arg, NULL); -  return new_str_token(s, hash); -} - -// Concatenate two tokens to create a new token. -static Token *paste(Token *lhs, Token *rhs) { -  // Paste the two tokens. -  char *buf = format("%.*s%.*s", lhs->len, lhs->loc, rhs->len, rhs->loc); - -  // Tokenize the resulting string. -  Token *tok = tokenize(new_file(lhs->file->name, lhs->file->file_no, buf)); -  if (tok->next->kind != TK_EOF) -    error_tok(lhs, "pasting forms '%s', an invalid token", buf); -  return tok; -} - -static bool has_varargs(MacroArg *args) { -  for (MacroArg *ap = args; ap; ap = ap->next) -    if (!strcmp(ap->name, "__VA_ARGS__")) -      return ap->tok->kind != TK_EOF; -  return false; -} - -// Replace func-like macro parameters with given arguments. -static Token *subst(Token *tok, MacroArg *args) { -  Token head = {}; -  Token *cur = &head; - -  while (tok->kind != TK_EOF) { -    // "#" followed by a parameter is replaced with stringized actuals. -    if (equal(tok, "#")) { -      MacroArg *arg = find_arg(args, tok->next); -      if (!arg) -        error_tok(tok->next, "'#' is not followed by a macro parameter"); -      cur = cur->next = stringize(tok, arg->tok); -      tok = tok->next->next; -      continue; -    } - -    // [GNU] If __VA_ARG__ is empty, `,##__VA_ARGS__` is expanded -    // to the empty token list. Otherwise, its expaned to `,` and -    // __VA_ARGS__. -    if (equal(tok, ",") && equal(tok->next, "##")) { -      MacroArg *arg = find_arg(args, tok->next->next); -      if (arg && arg->is_va_args) { -        if (arg->tok->kind == TK_EOF) { -          tok = tok->next->next->next; -        } else { -          cur = cur->next = copy_token(tok); -          tok = tok->next->next; -        } -        continue; -      } -    } - -    if (equal(tok, "##")) { -      if (cur == &head) -        error_tok(tok, "'##' cannot appear at start of macro expansion"); - -      if (tok->next->kind == TK_EOF) -        error_tok(tok, "'##' cannot appear at end of macro expansion"); - -      MacroArg *arg = find_arg(args, tok->next); -      if (arg) { -        if (arg->tok->kind != TK_EOF) { -          *cur = *paste(cur, arg->tok); -          for (Token *t = arg->tok->next; t->kind != TK_EOF; t = t->next) -            cur = cur->next = copy_token(t); -        } -        tok = tok->next->next; -        continue; -      } - -      *cur = *paste(cur, tok->next); -      tok = tok->next->next; -      continue; -    } - -    MacroArg *arg = find_arg(args, tok); - -    if (arg && equal(tok->next, "##")) { -      Token *rhs = tok->next->next; - -      if (arg->tok->kind == TK_EOF) { -        MacroArg *arg2 = find_arg(args, rhs); -        if (arg2) { -          for (Token *t = arg2->tok; t->kind != TK_EOF; t = t->next) -            cur = cur->next = copy_token(t); -        } else { -          cur = cur->next = copy_token(rhs); -        } -        tok = rhs->next; -        continue; -      } - -      for (Token *t = arg->tok; t->kind != TK_EOF; t = t->next) -        cur = cur->next = copy_token(t); -      tok = tok->next; -      continue; -    } - -    // If __VA_ARG__ is empty, __VA_OPT__(x) is expanded to the -    // empty token list. Otherwise, __VA_OPT__(x) is expanded to x. -    if (equal(tok, "__VA_OPT__") && equal(tok->next, "(")) { -      MacroArg *arg = read_macro_arg_one(&tok, tok->next->next, true); -      if (has_varargs(args)) -        for (Token *t = arg->tok; t->kind != TK_EOF; t = t->next) -          cur = cur->next = t; -      tok = skip(tok, ")"); -      continue; -    } - -    // Handle a macro token. Macro arguments are completely macro-expanded -    // before they are substituted into a macro body. -    if (arg) { -      Token *t = preprocess2(arg->tok); -      t->at_bol = tok->at_bol; -      t->has_space = tok->has_space; -      for (; t->kind != TK_EOF; t = t->next) -        cur = cur->next = copy_token(t); -      tok = tok->next; -      continue; -    } - -    // Handle a non-macro token. -    cur = cur->next = copy_token(tok); -    tok = tok->next; -    continue; -  } - -  cur->next = tok; -  return head.next; -} - -// If tok is a macro, expand it and return true. -// Otherwise, do nothing and return false. -static bool expand_macro(Token **rest, Token *tok) { -  if (hideset_contains(tok->hideset, tok->loc, tok->len)) -    return false; - -  Macro *m = find_macro(tok); -  if (!m) -    return false; - -  // Built-in dynamic macro application such as __LINE__ -  if (m->handler) { -    *rest = m->handler(tok); -    (*rest)->next = tok->next; -    return true; -  } - -  // Object-like macro application -  if (m->is_objlike) { -    Hideset *hs = hideset_union(tok->hideset, new_hideset(m->name)); -    Token *body = add_hideset(m->body, hs); -    for (Token *t = body; t->kind != TK_EOF; t = t->next) -      t->origin = tok; -    *rest = append(body, tok->next); -    (*rest)->at_bol = tok->at_bol; -    (*rest)->has_space = tok->has_space; -    return true; -  } - -  // If a funclike macro token is not followed by an argument list, -  // treat it as a normal identifier. -  if (!equal(tok->next, "(")) -    return false; - -  // Function-like macro application -  Token *macro_token = tok; -  MacroArg *args = read_macro_args(&tok, tok, m->params, m->va_args_name); -  Token *rparen = tok; - -  // Tokens that consist a func-like macro invocation may have different -  // hidesets, and if that's the case, it's not clear what the hideset -  // for the new tokens should be. We take the interesection of the -  // macro token and the closing parenthesis and use it as a new hideset -  // as explained in the Dave Prossor's algorithm. -  Hideset *hs = hideset_intersection(macro_token->hideset, rparen->hideset); -  hs = hideset_union(hs, new_hideset(m->name)); - -  Token *body = subst(m->body, args); -  body = add_hideset(body, hs); -  for (Token *t = body; t->kind != TK_EOF; t = t->next) -    t->origin = macro_token; -  *rest = append(body, tok->next); -  (*rest)->at_bol = macro_token->at_bol; -  (*rest)->has_space = macro_token->has_space; -  return true; -} - -char *search_include_paths(char *filename) { -  if (filename[0] == '/') -    return filename; - -  static HashMap cache; -  char *cached = hashmap_get(&cache, filename); -  if (cached) -    return cached; - -  // Search a file from the include paths. -  for (int i = 0; i < include_paths.len; i++) { -    char *path = format("%s/%s", include_paths.data[i], filename); -    if (!file_exists(path)) -      continue; -    hashmap_put(&cache, filename, path); -    include_next_idx = i + 1; -    return path; -  } -  return NULL; -} - -static char *search_include_next(char *filename) { -  for (; include_next_idx < include_paths.len; include_next_idx++) { -    char *path = format("%s/%s", include_paths.data[include_next_idx], filename); -    if (file_exists(path)) -      return path; -  } -  return NULL; -} - -// Read an #include argument. -static char *read_include_filename(Token **rest, Token *tok, bool *is_dquote) { -  // Pattern 1: #include "foo.h" -  if (tok->kind == TK_STR) { -    // A double-quoted filename for #include is a special kind of -    // token, and we don't want to interpret any escape sequences in it. -    // For example, "\f" in "C:\foo" is not a formfeed character but -    // just two non-control characters, backslash and f. -    // So we don't want to use token->str. -    *is_dquote = true; -    *rest = skip_line(tok->next); -    return strndup(tok->loc + 1, tok->len - 2); -  } - -  // Pattern 2: #include <foo.h> -  if (equal(tok, "<")) { -    // Reconstruct a filename from a sequence of tokens between -    // "<" and ">". -    Token *start = tok; - -    // Find closing ">". -    for (; !equal(tok, ">"); tok = tok->next) -      if (tok->at_bol || tok->kind == TK_EOF) -        error_tok(tok, "expected '>'"); - -    *is_dquote = false; -    *rest = skip_line(tok->next); -    return join_tokens(start->next, tok); -  } - -  // Pattern 3: #include FOO -  // In this case FOO must be macro-expanded to either -  // a single string token or a sequence of "<" ... ">". -  if (tok->kind == TK_IDENT) { -    Token *tok2 = preprocess2(copy_line(rest, tok)); -    return read_include_filename(&tok2, tok2, is_dquote); -  } - -  error_tok(tok, "expected a filename"); -} - -// Detect the following "include guard" pattern. -// -//   #ifndef FOO_H -//   #define FOO_H -//   ... -//   #endif -static char *detect_include_guard(Token *tok) { -  // Detect the first two lines. -  if (!is_hash(tok) || !equal(tok->next, "ifndef")) -    return NULL; -  tok = tok->next->next; - -  if (tok->kind != TK_IDENT) -    return NULL; - -  char *macro = strndup(tok->loc, tok->len); -  tok = tok->next; - -  if (!is_hash(tok) || !equal(tok->next, "define") || !equal(tok->next->next, macro)) -    return NULL; - -  // Read until the end of the file. -  while (tok->kind != TK_EOF) { -    if (!is_hash(tok)) { -      tok = tok->next; -      continue; -    } - -    if (equal(tok->next, "endif") && tok->next->next->kind == TK_EOF) -      return macro; - -    if (equal(tok, "if") || equal(tok, "ifdef") || equal(tok, "ifndef")) -      tok = skip_cond_incl(tok->next); -    else -      tok = tok->next; -  } -  return NULL; -} - -static Token *include_file(Token *tok, char *path, Token *filename_tok) { -  // Check for "#pragma once" -  if (hashmap_get(&pragma_once, path)) -    return tok; - -  // If we read the same file before, and if the file was guarded -  // by the usual #ifndef ... #endif pattern, we may be able to -  // skip the file without opening it. -  static HashMap include_guards; -  char *guard_name = hashmap_get(&include_guards, path); -  if (guard_name && hashmap_get(¯os, guard_name)) -    return tok; - -  Token *tok2 = tokenize_file(path); -  if (!tok2) -    error_tok(filename_tok, "%s: cannot open file: %s", path, strerror(errno)); - -  guard_name = detect_include_guard(tok2); -  if (guard_name) -    hashmap_put(&include_guards, path, guard_name); - -  return append(tok2, tok); -} - -// Read #line arguments -static void read_line_marker(Token **rest, Token *tok) { -  Token *start = tok; -  tok = preprocess(copy_line(rest, tok)); - -  if (tok->kind != TK_NUM || tok->ty->kind != TY_INT) -    error_tok(tok, "invalid line marker"); -  start->file->line_delta = tok->val - start->line_no; - -  tok = tok->next; -  if (tok->kind == TK_EOF) -    return; - -  if (tok->kind != TK_STR) -    error_tok(tok, "filename expected"); -  start->file->display_name = tok->str; -} - -// Visit all tokens in `tok` while evaluating preprocessing -// macros and directives. -static Token *preprocess2(Token *tok) { -  Token head = {}; -  Token *cur = &head; - -  while (tok->kind != TK_EOF) { -    // If it is a macro, expand it. -    if (expand_macro(&tok, tok)) -      continue; - -    // Pass through if it is not a "#". -    if (!is_hash(tok)) { -      tok->line_delta = tok->file->line_delta; -      tok->filename = tok->file->display_name; -      cur = cur->next = tok; -      tok = tok->next; -      continue; -    } - -    Token *start = tok; -    tok = tok->next; - -    if (equal(tok, "include")) { -      bool is_dquote; -      char *filename = read_include_filename(&tok, tok->next, &is_dquote); - -      if (filename[0] != '/' && is_dquote) { -        char *path = format("%s/%s", dirname(strdup(start->file->name)), filename); -        if (file_exists(path)) { -          tok = include_file(tok, path, start->next->next); -          continue; -        } -      } - -      char *path = search_include_paths(filename); -      tok = include_file(tok, path ? path : filename, start->next->next); -      continue; -    } - -    if (equal(tok, "include_next")) { -      bool ignore; -      char *filename = read_include_filename(&tok, tok->next, &ignore); -      char *path = search_include_next(filename); -      tok = include_file(tok, path ? path : filename, start->next->next); -      continue; -    } - -    if (equal(tok, "define")) { -      read_macro_definition(&tok, tok->next); -      continue; -    } - -    if (equal(tok, "undef")) { -      tok = tok->next; -      if (tok->kind != TK_IDENT) -        error_tok(tok, "macro name must be an identifier"); -      undef_macro(strndup(tok->loc, tok->len)); -      tok = skip_line(tok->next); -      continue; -    } - -    if (equal(tok, "if")) { -      long val = eval_const_expr(&tok, tok); -      push_cond_incl(start, val); -      if (!val) -        tok = skip_cond_incl(tok); -      continue; -    } - -    if (equal(tok, "ifdef")) { -      bool defined = find_macro(tok->next); -      push_cond_incl(tok, defined); -      tok = skip_line(tok->next->next); -      if (!defined) -        tok = skip_cond_incl(tok); -      continue; -    } - -    if (equal(tok, "ifndef")) { -      bool defined = find_macro(tok->next); -      push_cond_incl(tok, !defined); -      tok = skip_line(tok->next->next); -      if (defined) -        tok = skip_cond_incl(tok); -      continue; -    } - -    if (equal(tok, "elif")) { -      if (!cond_incl || cond_incl->ctx == IN_ELSE) -        error_tok(start, "stray #elif"); -      cond_incl->ctx = IN_ELIF; - -      if (!cond_incl->included && eval_const_expr(&tok, tok)) -        cond_incl->included = true; -      else -        tok = skip_cond_incl(tok); -      continue; -    } - -    if (equal(tok, "else")) { -      if (!cond_incl || cond_incl->ctx == IN_ELSE) -        error_tok(start, "stray #else"); -      cond_incl->ctx = IN_ELSE; -      tok = skip_line(tok->next); - -      if (cond_incl->included) -        tok = skip_cond_incl(tok); -      continue; -    } - -    if (equal(tok, "endif")) { -      if (!cond_incl) -        error_tok(start, "stray #endif"); -      cond_incl = cond_incl->next; -      tok = skip_line(tok->next); -      continue; -    } - -    if (equal(tok, "line")) { -      read_line_marker(&tok, tok->next); -      continue; -    } - -    if (tok->kind == TK_PP_NUM) { -      read_line_marker(&tok, tok); -      continue; -    } - -    if (equal(tok, "pragma") && equal(tok->next, "once")) { -      hashmap_put(&pragma_once, tok->file->name, (void *)1); -      tok = skip_line(tok->next->next); -      continue; -    } - -    if (equal(tok, "pragma")) { -      do { -        tok = tok->next; -      } while (!tok->at_bol); -      continue; -    } - -    if (equal(tok, "error")) -      error_tok(tok, "error"); - -    // `#`-only line is legal. It's called a null directive. -    if (tok->at_bol) -      continue; - -    error_tok(tok, "invalid preprocessor directive"); -  } - -  cur->next = tok; -  return head.next; -} - -void define_macro(char *name, char *buf) { -  Token *tok = tokenize(new_file("<built-in>", 1, buf)); -  add_macro(name, true, tok); -} - -void undef_macro(char *name) { -  hashmap_delete(¯os, name); -} - -static Macro *add_builtin(char *name, macro_handler_fn *fn) { -  Macro *m = add_macro(name, true, NULL); -  m->handler = fn; -  return m; -} - -static Token *file_macro(Token *tmpl) { -  while (tmpl->origin) -    tmpl = tmpl->origin; -  return new_str_token(tmpl->file->display_name, tmpl); -} - -static Token *line_macro(Token *tmpl) { -  while (tmpl->origin) -    tmpl = tmpl->origin; -  int i = tmpl->line_no + tmpl->file->line_delta; -  return new_num_token(i, tmpl); -} - -// __COUNTER__ is expanded to serial values starting from 0. -static Token *counter_macro(Token *tmpl) { -  static int i = 0; -  return new_num_token(i++, tmpl); -} - -// __TIMESTAMP__ is expanded to a string describing the last -// modification time of the current file. E.g. -// "Fri Jul 24 01:32:50 2020" -static Token *timestamp_macro(Token *tmpl) { -  struct stat st; -  if (stat(tmpl->file->name, &st) != 0) -    return new_str_token("??? ??? ?? ??:??:?? ????", tmpl); - -  char buf[30]; -  ctime_r(&st.st_mtime, buf); -  buf[24] = '\0'; -  return new_str_token(buf, tmpl); -} - -static Token *base_file_macro(Token *tmpl) { -  return new_str_token(base_file, tmpl); -} - -// __DATE__ is expanded to the current date, e.g. "May 17 2020". -static char *format_date(struct tm *tm) { -  static char mon[][4] = { -    "Jan", "Feb", "Mar", "Apr", "May", "Jun", -    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", -  }; - -  return format("\"%s %2d %d\"", mon[tm->tm_mon], tm->tm_mday, tm->tm_year + 1900); -} - -// __TIME__ is expanded to the current time, e.g. "13:34:03". -static char *format_time(struct tm *tm) { -  return format("\"%02d:%02d:%02d\"", tm->tm_hour, tm->tm_min, tm->tm_sec); -} - -void init_macros(void) { -  // Define predefined macros -  define_macro("_LP64", "1"); -  define_macro("__C99_MACRO_WITH_VA_ARGS", "1"); -  define_macro("__ELF__", "1"); -  define_macro("__LP64__", "1"); -  define_macro("__SIZEOF_DOUBLE__", "8"); -  define_macro("__SIZEOF_FLOAT__", "4"); -  define_macro("__SIZEOF_INT__", "4"); -  define_macro("__SIZEOF_LONG_DOUBLE__", "8"); -  define_macro("__SIZEOF_LONG_LONG__", "8"); -  define_macro("__SIZEOF_LONG__", "8"); -  define_macro("__SIZEOF_POINTER__", "8"); -  define_macro("__SIZEOF_PTRDIFF_T__", "8"); -  define_macro("__SIZEOF_SHORT__", "2"); -  define_macro("__SIZEOF_SIZE_T__", "8"); -  define_macro("__SIZE_TYPE__", "unsigned long"); -  define_macro("__STDC_HOSTED__", "1"); -  define_macro("__STDC_NO_COMPLEX__", "1"); -  define_macro("__STDC_UTF_16__", "1"); -  define_macro("__STDC_UTF_32__", "1"); -  define_macro("__STDC_VERSION__", "201112L"); -  define_macro("__STDC__", "1"); -  define_macro("__USER_LABEL_PREFIX__", ""); -  define_macro("__alignof__", "_Alignof"); -  define_macro("__amd64", "1"); -  define_macro("__amd64__", "1"); -  define_macro("__chibicc__", "1"); -  define_macro("__const__", "const"); -  define_macro("__gnu_linux__", "1"); -  define_macro("__inline__", "inline"); -  define_macro("__linux", "1"); -  define_macro("__linux__", "1"); -  define_macro("__signed__", "signed"); -  define_macro("__typeof__", "typeof"); -  define_macro("__unix", "1"); -  define_macro("__unix__", "1"); -  define_macro("__volatile__", "volatile"); -  define_macro("__x86_64", "1"); -  define_macro("__x86_64__", "1"); -  define_macro("linux", "1"); -  define_macro("unix", "1"); - -  add_builtin("__FILE__", file_macro); -  add_builtin("__LINE__", line_macro); -  add_builtin("__COUNTER__", counter_macro); -  add_builtin("__TIMESTAMP__", timestamp_macro); -  add_builtin("__BASE_FILE__", base_file_macro); - -  time_t now = time(NULL); -  struct tm *tm = localtime(&now); -  define_macro("__DATE__", format_date(tm)); -  define_macro("__TIME__", format_time(tm)); -} - -typedef enum { -  STR_NONE, STR_UTF8, STR_UTF16, STR_UTF32, STR_WIDE, -} StringKind; - -static StringKind getStringKind(Token *tok) { -  if (!strcmp(tok->loc, "u8")) -    return STR_UTF8; - -  switch (tok->loc[0]) { -  case '"': return STR_NONE; -  case 'u': return STR_UTF16; -  case 'U': return STR_UTF32; -  case 'L': return STR_WIDE; -  } -  unreachable(); -} - -// Concatenate adjacent string literals into a single string literal -// as per the C spec. -static void join_adjacent_string_literals(Token *tok) { -  // First pass: If regular string literals are adjacent to wide -  // string literals, regular string literals are converted to a wide -  // type before concatenation. In this pass, we do the conversion. -  for (Token *tok1 = tok; tok1->kind != TK_EOF;) { -    if (tok1->kind != TK_STR || tok1->next->kind != TK_STR) { -      tok1 = tok1->next; -      continue; -    } - -    StringKind kind = getStringKind(tok1); -    Type *basety = tok1->ty->base; - -    for (Token *t = tok1->next; t->kind == TK_STR; t = t->next) { -      StringKind k = getStringKind(t); -      if (kind == STR_NONE) { -        kind = k; -        basety = t->ty->base; -      } else if (k != STR_NONE && kind != k) { -        error_tok(t, "unsupported non-standard concatenation of string literals"); -      } -    } - -    if (basety->size > 1) -      for (Token *t = tok1; t->kind == TK_STR; t = t->next) -        if (t->ty->base->size == 1) -          *t = *tokenize_string_literal(t, basety); - -    while (tok1->kind == TK_STR) -      tok1 = tok1->next; -  } - -  // Second pass: concatenate adjacent string literals. -  for (Token *tok1 = tok; tok1->kind != TK_EOF;) { -    if (tok1->kind != TK_STR || tok1->next->kind != TK_STR) { -      tok1 = tok1->next; -      continue; -    } - -    Token *tok2 = tok1->next; -    while (tok2->kind == TK_STR) -      tok2 = tok2->next; - -    int len = tok1->ty->array_len; -    for (Token *t = tok1->next; t != tok2; t = t->next) -      len = len + t->ty->array_len - 1; - -    char *buf = calloc(tok1->ty->base->size, len); - -    int i = 0; -    for (Token *t = tok1; t != tok2; t = t->next) { -      memcpy(buf + i, t->str, t->ty->size); -      i = i + t->ty->size - t->ty->base->size; -    } - -    *tok1 = *copy_token(tok1); -    tok1->ty = array_of(tok1->ty->base, len); -    tok1->str = buf; -    tok1->next = tok2; -    tok1 = tok2; -  } -} - -// Entry point function of the preprocessor. -Token *preprocess(Token *tok) { -  tok = preprocess2(tok); -  if (cond_incl) -    error_tok(cond_incl->tok, "unterminated conditional directive"); -  convert_pp_tokens(tok); -  join_adjacent_string_literals(tok); - -  for (Token *t = tok; t; t = t->next) -    t->line_no += t->line_delta; -  return tok; -} diff --git a/src/3p/chibicc/type.c b/src/3p/chibicc/type.c deleted file mode 100644 index 02ade59..0000000 --- a/src/3p/chibicc/type.c +++ /dev/null @@ -1,307 +0,0 @@ -#include "chibicc.h" - -Type *ty_void = &(Type){TY_VOID, 1, 1}; -Type *ty_bool = &(Type){TY_BOOL, 1, 1}; - -Type *ty_char = &(Type){TY_CHAR, 1, 1}; -Type *ty_short = &(Type){TY_SHORT, 2, 2}; -Type *ty_int = &(Type){TY_INT, 4, 4}; -Type *ty_long = &(Type){TY_LONG, 8, 8}; - -Type *ty_uchar = &(Type){TY_CHAR, 1, 1, true}; -Type *ty_ushort = &(Type){TY_SHORT, 2, 2, true}; -Type *ty_uint = &(Type){TY_INT, 4, 4, true}; -Type *ty_ulong = &(Type){TY_LONG, 8, 8, true}; - -Type *ty_float = &(Type){TY_FLOAT, 4, 4}; -Type *ty_double = &(Type){TY_DOUBLE, 8, 8}; -Type *ty_ldouble = &(Type){TY_LDOUBLE, 16, 16}; - -static Type *new_type(TypeKind kind, int size, int align) { -  Type *ty = calloc(1, sizeof(Type)); -  ty->kind = kind; -  ty->size = size; -  ty->align = align; -  return ty; -} - -bool is_integer(Type *ty) { -  TypeKind k = ty->kind; -  return k == TY_BOOL || k == TY_CHAR || k == TY_SHORT || -         k == TY_INT  || k == TY_LONG || k == TY_ENUM; -} - -bool is_flonum(Type *ty) { -  return ty->kind == TY_FLOAT || ty->kind == TY_DOUBLE || -         ty->kind == TY_LDOUBLE; -} - -bool is_numeric(Type *ty) { -  return is_integer(ty) || is_flonum(ty); -} - -bool is_compatible(Type *t1, Type *t2) { -  if (t1 == t2) -    return true; - -  if (t1->origin) -    return is_compatible(t1->origin, t2); - -  if (t2->origin) -    return is_compatible(t1, t2->origin); - -  if (t1->kind != t2->kind) -    return false; - -  switch (t1->kind) { -  case TY_CHAR: -  case TY_SHORT: -  case TY_INT: -  case TY_LONG: -    return t1->is_unsigned == t2->is_unsigned; -  case TY_FLOAT: -  case TY_DOUBLE: -  case TY_LDOUBLE: -    return true; -  case TY_PTR: -    return is_compatible(t1->base, t2->base); -  case TY_FUNC: { -    if (!is_compatible(t1->return_ty, t2->return_ty)) -      return false; -    if (t1->is_variadic != t2->is_variadic) -      return false; - -    Type *p1 = t1->params; -    Type *p2 = t2->params; -    for (; p1 && p2; p1 = p1->next, p2 = p2->next) -      if (!is_compatible(p1, p2)) -        return false; -    return p1 == NULL && p2 == NULL; -  } -  case TY_ARRAY: -    if (!is_compatible(t1->base, t2->base)) -      return false; -    return t1->array_len < 0 && t2->array_len < 0 && -           t1->array_len == t2->array_len; -  } -  return false; -} - -Type *copy_type(Type *ty) { -  Type *ret = calloc(1, sizeof(Type)); -  *ret = *ty; -  ret->origin = ty; -  return ret; -} - -Type *pointer_to(Type *base) { -  Type *ty = new_type(TY_PTR, 8, 8); -  ty->base = base; -  ty->is_unsigned = true; -  return ty; -} - -Type *func_type(Type *return_ty) { -  // The C spec disallows sizeof(<function type>), but -  // GCC allows that and the expression is evaluated to 1. -  Type *ty = new_type(TY_FUNC, 1, 1); -  ty->return_ty = return_ty; -  return ty; -} - -Type *array_of(Type *base, int len) { -  Type *ty = new_type(TY_ARRAY, base->size * len, base->align); -  ty->base = base; -  ty->array_len = len; -  return ty; -} - -Type *vla_of(Type *base, Node *len) { -  Type *ty = new_type(TY_VLA, 8, 8); -  ty->base = base; -  ty->vla_len = len; -  return ty; -} - -Type *enum_type(void) { -  return new_type(TY_ENUM, 4, 4); -} - -Type *struct_type(void) { -  return new_type(TY_STRUCT, 0, 1); -} - -static Type *get_common_type(Type *ty1, Type *ty2) { -  if (ty1->base) -    return pointer_to(ty1->base); - -  if (ty1->kind == TY_FUNC) -    return pointer_to(ty1); -  if (ty2->kind == TY_FUNC) -    return pointer_to(ty2); - -  if (ty1->kind == TY_LDOUBLE || ty2->kind == TY_LDOUBLE) -    return ty_ldouble; -  if (ty1->kind == TY_DOUBLE || ty2->kind == TY_DOUBLE) -    return ty_double; -  if (ty1->kind == TY_FLOAT || ty2->kind == TY_FLOAT) -    return ty_float; - -  if (ty1->size < 4) -    ty1 = ty_int; -  if (ty2->size < 4) -    ty2 = ty_int; - -  if (ty1->size != ty2->size) -    return (ty1->size < ty2->size) ? ty2 : ty1; - -  if (ty2->is_unsigned) -    return ty2; -  return ty1; -} - -// For many binary operators, we implicitly promote operands so that -// both operands have the same type. Any integral type smaller than -// int is always promoted to int. If the type of one operand is larger -// than the other's (e.g. "long" vs. "int"), the smaller operand will -// be promoted to match with the other. -// -// This operation is called the "usual arithmetic conversion". -static void usual_arith_conv(Node **lhs, Node **rhs) { -  Type *ty = get_common_type((*lhs)->ty, (*rhs)->ty); -  *lhs = new_cast(*lhs, ty); -  *rhs = new_cast(*rhs, ty); -} - -void add_type(Node *node) { -  if (!node || node->ty) -    return; - -  add_type(node->lhs); -  add_type(node->rhs); -  add_type(node->cond); -  add_type(node->then); -  add_type(node->els); -  add_type(node->init); -  add_type(node->inc); - -  for (Node *n = node->body; n; n = n->next) -    add_type(n); -  for (Node *n = node->args; n; n = n->next) -    add_type(n); - -  switch (node->kind) { -  case ND_NUM: -    node->ty = ty_int; -    return; -  case ND_ADD: -  case ND_SUB: -  case ND_MUL: -  case ND_DIV: -  case ND_MOD: -  case ND_BITAND: -  case ND_BITOR: -  case ND_BITXOR: -    usual_arith_conv(&node->lhs, &node->rhs); -    node->ty = node->lhs->ty; -    return; -  case ND_NEG: { -    Type *ty = get_common_type(ty_int, node->lhs->ty); -    node->lhs = new_cast(node->lhs, ty); -    node->ty = ty; -    return; -  } -  case ND_ASSIGN: -    if (node->lhs->ty->kind == TY_ARRAY) -      error_tok(node->lhs->tok, "not an lvalue"); -    if (node->lhs->ty->kind != TY_STRUCT) -      node->rhs = new_cast(node->rhs, node->lhs->ty); -    node->ty = node->lhs->ty; -    return; -  case ND_EQ: -  case ND_NE: -  case ND_LT: -  case ND_LE: -    usual_arith_conv(&node->lhs, &node->rhs); -    node->ty = ty_int; -    return; -  case ND_FUNCALL: -    node->ty = node->func_ty->return_ty; -    return; -  case ND_NOT: -  case ND_LOGOR: -  case ND_LOGAND: -    node->ty = ty_int; -    return; -  case ND_BITNOT: -  case ND_SHL: -  case ND_SHR: -    node->ty = node->lhs->ty; -    return; -  case ND_VAR: -  case ND_VLA_PTR: -    node->ty = node->var->ty; -    return; -  case ND_COND: -    if (node->then->ty->kind == TY_VOID || node->els->ty->kind == TY_VOID) { -      node->ty = ty_void; -    } else { -      usual_arith_conv(&node->then, &node->els); -      node->ty = node->then->ty; -    } -    return; -  case ND_COMMA: -    node->ty = node->rhs->ty; -    return; -  case ND_MEMBER: -    node->ty = node->member->ty; -    return; -  case ND_ADDR: { -    Type *ty = node->lhs->ty; -    if (ty->kind == TY_ARRAY) -      node->ty = pointer_to(ty->base); -    else -      node->ty = pointer_to(ty); -    return; -  } -  case ND_DEREF: -    if (!node->lhs->ty->base) -      error_tok(node->tok, "invalid pointer dereference"); -    if (node->lhs->ty->base->kind == TY_VOID) -      error_tok(node->tok, "dereferencing a void pointer"); - -    node->ty = node->lhs->ty->base; -    return; -  case ND_STMT_EXPR: -    if (node->body) { -      Node *stmt = node->body; -      while (stmt->next) -        stmt = stmt->next; -      if (stmt->kind == ND_EXPR_STMT) { -        node->ty = stmt->lhs->ty; -        return; -      } -    } -    error_tok(node->tok, "statement expression returning void is not supported"); -    return; -  case ND_LABEL_VAL: -    node->ty = pointer_to(ty_void); -    return; -  case ND_CAS: -    add_type(node->cas_addr); -    add_type(node->cas_old); -    add_type(node->cas_new); -    node->ty = ty_bool; - -    if (node->cas_addr->ty->kind != TY_PTR) -      error_tok(node->cas_addr->tok, "pointer expected"); -    if (node->cas_old->ty->kind != TY_PTR) -      error_tok(node->cas_old->tok, "pointer expected"); -    return; -  case ND_EXCH: -    if (node->lhs->ty->kind != TY_PTR) -      error_tok(node->cas_addr->tok, "pointer expected"); -    node->ty = node->lhs->ty->base; -    return; -  } -}  | 
