Remove some unused files

1 files changed, 0 insertions, 1595 deletions

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);
-}