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gen.c
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gen.c
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// Copyright 2012 Rui Ueyama. Released under the MIT license.
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "8cc.h"
bool dumpstack = false;
bool dumpsource = true;
static char *REGS[] = {"rdi", "rsi", "rdx", "rcx", "r8", "r9"};
static char *SREGS[] = {"dil", "sil", "dl", "cl", "r8b", "r9b"};
static char *MREGS[] = {"edi", "esi", "edx", "ecx", "r8d", "r9d"};
static int TAB = 8;
static Vector *functions = &EMPTY_VECTOR;
static int stackpos;
static int numgp;
static int numfp;
static FILE *outputfp;
static Map *source_files = &EMPTY_MAP;
static Map *source_lines = &EMPTY_MAP;
static char *last_loc = "";
static void emit_addr(Node *node);
static void emit_expr(Node *node);
static void emit_decl_init(Vector *inits, int off, int totalsize);
static void do_emit_data(Vector *inits, int size, int off, int depth);
static void emit_data(Node *v, int off, int depth);
#define REGAREA_SIZE 176
#define emit(...) emitf(__LINE__, "\t" __VA_ARGS__)
#define emit_noindent(...) emitf(__LINE__, __VA_ARGS__)
#ifdef __GNUC__
#define SAVE \
int save_hook __attribute__((unused, cleanup(pop_function))); \
if (dumpstack) \
vec_push(functions, (void *)__func__);
static void pop_function(void *ignore) {
if (dumpstack)
vec_pop(functions);
}
#else
#define SAVE
#endif
static char *get_caller_list() {
Buffer *b = make_buffer();
for (int i = 0; i < vec_len(functions); i++) {
if (i > 0)
buf_printf(b, " -> ");
buf_printf(b, "%s", vec_get(functions, i));
}
buf_write(b, '\0');
return buf_body(b);
}
void set_output_file(FILE *fp) {
outputfp = fp;
}
void close_output_file() {
fclose(outputfp);
}
static void emitf(int line, char *fmt, ...) {
// Replace "#" with "%%" so that vfprintf prints out "#" as "%".
char buf[256];
int i = 0;
for (char *p = fmt; *p; p++) {
assert(i < sizeof(buf) - 3);
if (*p == '#') {
buf[i++] = '%';
buf[i++] = '%';
} else {
buf[i++] = *p;
}
}
buf[i] = '\0';
va_list args;
va_start(args, fmt);
int col = vfprintf(outputfp, buf, args);
va_end(args);
if (dumpstack) {
for (char *p = fmt; *p; p++)
if (*p == '\t')
col += TAB - 1;
int space = (28 - col) > 0 ? (30 - col) : 2;
fprintf(outputfp, "%*c %s:%d", space, '#', get_caller_list(), line);
}
fprintf(outputfp, "\n");
}
static void emit_nostack(char *fmt, ...) {
fprintf(outputfp, "\t");
va_list args;
va_start(args, fmt);
vfprintf(outputfp, fmt, args);
va_end(args);
fprintf(outputfp, "\n");
}
static char *get_int_reg(Type *ty, char r) {
assert(r == 'a' || r == 'c');
switch (ty->size) {
case 1: return (r == 'a') ? "al" : "cl";
case 2: return (r == 'a') ? "ax" : "cx";
case 4: return (r == 'a') ? "eax" : "ecx";
case 8: return (r == 'a') ? "rax" : "rcx";
default:
error("Unknown data size: %s: %d", ty2s(ty), ty->size);
}
}
static char *get_load_inst(Type *ty) {
switch (ty->size) {
case 1: return "movsbq";
case 2: return "movswq";
case 4: return "movslq";
case 8: return "mov";
default:
error("Unknown data size: %s: %d", ty2s(ty), ty->size);
}
}
static int align(int n, int m) {
int rem = n % m;
return (rem == 0) ? n : n - rem + m;
}
static void push_xmm(int reg) {
SAVE;
emit("sub $8, #rsp");
emit("movsd #xmm%d, (#rsp)", reg);
stackpos += 8;
}
static void pop_xmm(int reg) {
SAVE;
emit("movsd (#rsp), #xmm%d", reg);
emit("add $8, #rsp");
stackpos -= 8;
assert(stackpos >= 0);
}
static void push(char *reg) {
SAVE;
emit("push #%s", reg);
stackpos += 8;
}
static void pop(char *reg) {
SAVE;
emit("pop #%s", reg);
stackpos -= 8;
assert(stackpos >= 0);
}
static int push_struct(int size) {
SAVE;
int aligned = align(size, 8);
emit("sub $%d, #rsp", aligned);
emit("mov #rcx, -8(#rsp)");
emit("mov #r11, -16(#rsp)");
emit("mov #rax, #rcx");
int i = 0;
for (; i < size; i += 8) {
emit("movq %d(#rcx), #r11", i);
emit("mov #r11, %d(#rsp)", i);
}
for (; i < size; i += 4) {
emit("movl %d(#rcx), #r11", i);
emit("movl #r11d, %d(#rsp)", i);
}
for (; i < size; i++) {
emit("movb %d(#rcx), #r11", i);
emit("movb #r11b, %d(#rsp)", i);
}
emit("mov -8(#rsp), #rcx");
emit("mov -16(#rsp), #r11");
stackpos += aligned;
return aligned;
}
static void maybe_emit_bitshift_load(Type *ty) {
SAVE;
if (ty->bitsize <= 0)
return;
emit("shr $%d, #rax", ty->bitoff);
push("rcx");
emit("mov $0x%lx, #rcx", (1 << (long)ty->bitsize) - 1);
emit("and #rcx, #rax");
pop("rcx");
}
static void maybe_emit_bitshift_save(Type *ty, char *addr) {
SAVE;
if (ty->bitsize <= 0)
return;
push("rcx");
push("rdi");
emit("mov $0x%lx, #rdi", (1 << (long)ty->bitsize) - 1);
emit("and #rdi, #rax");
emit("shl $%d, #rax", ty->bitoff);
emit("mov %s, #%s", addr, get_int_reg(ty, 'c'));
emit("mov $0x%lx, #rdi", ~(((1 << (long)ty->bitsize) - 1) << ty->bitoff));
emit("and #rdi, #rcx");
emit("or #rcx, #rax");
pop("rdi");
pop("rcx");
}
static void emit_gload(Type *ty, char *label, int off) {
SAVE;
if (ty->kind == KIND_ARRAY) {
if (off)
emit("lea %s+%d(#rip), #rax", label, off);
else
emit("lea %s(#rip), #rax", label);
return;
}
char *inst = get_load_inst(ty);
emit("%s %s+%d(#rip), #rax", inst, label, off);
maybe_emit_bitshift_load(ty);
}
static void emit_intcast(Type *ty) {
switch(ty->kind) {
case KIND_BOOL:
case KIND_CHAR:
ty->usig ? emit("movzbq #al, #rax") : emit("movsbq #al, #rax");
return;
case KIND_SHORT:
ty->usig ? emit("movzwq #ax, #rax") : emit("movswq #ax, #rax");
return;
case KIND_INT:
ty->usig ? emit("mov #eax, #eax") : emit("cltq");
return;
case KIND_LONG:
case KIND_LLONG:
return;
}
}
static void emit_toint(Type *ty) {
SAVE;
if (ty->kind == KIND_FLOAT)
emit("cvttss2si #xmm0, #eax");
else if (ty->kind == KIND_DOUBLE)
emit("cvttsd2si #xmm0, #eax");
}
static void emit_lload(Type *ty, char *base, int off) {
SAVE;
if (ty->kind == KIND_ARRAY) {
emit("lea %d(#%s), #rax", off, base);
} else if (ty->kind == KIND_FLOAT) {
emit("movss %d(#%s), #xmm0", off, base);
} else if (ty->kind == KIND_DOUBLE || ty->kind == KIND_LDOUBLE) {
emit("movsd %d(#%s), #xmm0", off, base);
} else {
char *inst = get_load_inst(ty);
emit("%s %d(#%s), #rax", inst, off, base);
maybe_emit_bitshift_load(ty);
}
}
static void maybe_convert_bool(Type *ty) {
if (ty->kind == KIND_BOOL) {
emit("test #rax, #rax");
emit("setne #al");
}
}
static void emit_gsave(char *varname, Type *ty, int off) {
SAVE;
assert(ty->kind != KIND_ARRAY);
maybe_convert_bool(ty);
char *reg = get_int_reg(ty, 'a');
char *addr = format("%s+%d(%%rip)", varname, off);
maybe_emit_bitshift_save(ty, addr);
emit("mov #%s, %s", reg, addr);
}
static void emit_lsave(Type *ty, int off) {
SAVE;
if (ty->kind == KIND_FLOAT) {
emit("movss #xmm0, %d(#rbp)", off);
} else if (ty->kind == KIND_DOUBLE) {
emit("movsd #xmm0, %d(#rbp)", off);
} else {
maybe_convert_bool(ty);
char *reg = get_int_reg(ty, 'a');
char *addr = format("%d(%%rbp)", off);
maybe_emit_bitshift_save(ty, addr);
emit("mov #%s, %s", reg, addr);
}
}
static void do_emit_assign_deref(Type *ty, int off) {
SAVE;
emit("mov (#rsp), #rcx");
char *reg = get_int_reg(ty, 'c');
if (off)
emit("mov #%s, %d(#rax)", reg, off);
else
emit("mov #%s, (#rax)", reg);
pop("rax");
}
static void emit_assign_deref(Node *var) {
SAVE;
push("rax");
emit_expr(var->operand);
do_emit_assign_deref(var->operand->ty->ptr, 0);
}
static void emit_pointer_arith(char kind, Node *left, Node *right) {
SAVE;
emit_expr(left);
push("rcx");
push("rax");
emit_expr(right);
int size = left->ty->ptr->size;
if (size > 1)
emit("imul $%d, #rax", size);
emit("mov #rax, #rcx");
pop("rax");
switch (kind) {
case '+': emit("add #rcx, #rax"); break;
case '-': emit("sub #rcx, #rax"); break;
default: error("invalid operator '%d'", kind);
}
pop("rcx");
}
static void emit_zero_filler(int start, int end) {
SAVE;
for (; start <= end - 4; start += 4)
emit("movl $0, %d(#rbp)", start);
for (; start < end; start++)
emit("movb $0, %d(#rbp)", start);
}
static void ensure_lvar_init(Node *node) {
SAVE;
assert(node->kind == AST_LVAR);
if (node->lvarinit)
emit_decl_init(node->lvarinit, node->loff, node->ty->size);
node->lvarinit = NULL;
}
static void emit_assign_struct_ref(Node *struc, Type *field, int off) {
SAVE;
switch (struc->kind) {
case AST_LVAR:
ensure_lvar_init(struc);
emit_lsave(field, struc->loff + field->offset + off);
break;
case AST_GVAR:
emit_gsave(struc->glabel, field, field->offset + off);
break;
case AST_STRUCT_REF:
emit_assign_struct_ref(struc->struc, field, off + struc->ty->offset);
break;
case AST_DEREF:
push("rax");
emit_expr(struc->operand);
do_emit_assign_deref(field, field->offset + off);
break;
default:
error("internal error: %s", node2s(struc));
}
}
static void emit_load_struct_ref(Node *struc, Type *field, int off) {
SAVE;
switch (struc->kind) {
case AST_LVAR:
ensure_lvar_init(struc);
emit_lload(field, "rbp", struc->loff + field->offset + off);
break;
case AST_GVAR:
emit_gload(field, struc->glabel, field->offset + off);
break;
case AST_STRUCT_REF:
emit_load_struct_ref(struc->struc, field, struc->ty->offset + off);
break;
case AST_DEREF:
emit_expr(struc->operand);
emit_lload(field, "rax", field->offset + off);
break;
default:
error("internal error: %s", node2s(struc));
}
}
static void emit_store(Node *var) {
SAVE;
switch (var->kind) {
case AST_DEREF: emit_assign_deref(var); break;
case AST_STRUCT_REF: emit_assign_struct_ref(var->struc, var->ty, 0); break;
case AST_LVAR:
ensure_lvar_init(var);
emit_lsave(var->ty, var->loff);
break;
case AST_GVAR: emit_gsave(var->glabel, var->ty, 0); break;
default: error("internal error");
}
}
static void emit_to_bool(Type *ty) {
SAVE;
if (is_flotype(ty)) {
push_xmm(1);
emit("xorpd #xmm1, #xmm1");
emit("%s #xmm1, #xmm0", (ty->kind == KIND_FLOAT) ? "ucomiss" : "ucomisd");
emit("setne #al");
pop_xmm(1);
} else {
emit("cmp $0, #rax");
emit("setne #al");
}
emit("movzb #al, #eax");
}
static void emit_comp(char *inst, char *usiginst, Node *node) {
SAVE;
if (is_flotype(node->left->ty)) {
emit_expr(node->left);
push_xmm(0);
emit_expr(node->right);
pop_xmm(1);
if (node->left->ty->kind == KIND_FLOAT)
emit("ucomiss #xmm0, #xmm1");
else
emit("ucomisd #xmm0, #xmm1");
} else {
emit_expr(node->left);
push("rax");
emit_expr(node->right);
pop("rcx");
int kind = node->left->ty->kind;
if (kind == KIND_LONG || kind == KIND_LLONG)
emit("cmp #rax, #rcx");
else
emit("cmp #eax, #ecx");
}
if (is_flotype(node->left->ty) || node->left->ty->usig)
emit("%s #al", usiginst);
else
emit("%s #al", inst);
emit("movzb #al, #eax");
}
static void emit_binop_int_arith(Node *node) {
SAVE;
char *op = NULL;
switch (node->kind) {
case '+': op = "add"; break;
case '-': op = "sub"; break;
case '*': op = "imul"; break;
case '^': op = "xor"; break;
case OP_SAL: op = "sal"; break;
case OP_SAR: op = "sar"; break;
case OP_SHR: op = "shr"; break;
case '/': case '%': break;
default: error("invalid operator '%d'", node->kind);
}
emit_expr(node->left);
push("rax");
emit_expr(node->right);
emit("mov #rax, #rcx");
pop("rax");
if (node->kind == '/' || node->kind == '%') {
if (node->ty->usig) {
emit("xor #edx, #edx");
emit("div #rcx");
} else {
emit("cqto");
emit("idiv #rcx");
}
if (node->kind == '%')
emit("mov #edx, #eax");
} else if (node->kind == OP_SAL || node->kind == OP_SAR || node->kind == OP_SHR) {
emit("%s #cl, #%s", op, get_int_reg(node->left->ty, 'a'));
} else {
emit("%s #rcx, #rax", op);
}
}
static void emit_binop_float_arith(Node *node) {
SAVE;
char *op;
bool isdouble = (node->ty->kind == KIND_DOUBLE);
switch (node->kind) {
case '+': op = (isdouble ? "addsd" : "addss"); break;
case '-': op = (isdouble ? "subsd" : "subss"); break;
case '*': op = (isdouble ? "mulsd" : "mulss"); break;
case '/': op = (isdouble ? "divsd" : "divss"); break;
default: error("invalid operator '%d'", node->kind);
}
emit_expr(node->left);
push_xmm(0);
emit_expr(node->right);
emit("%s #xmm0, #xmm1", (isdouble ? "movsd" : "movss"));
pop_xmm(0);
emit("%s #xmm1, #xmm0", op);
}
static void emit_load_convert(Type *to, Type *from) {
SAVE;
if (is_inttype(from) && to->kind == KIND_FLOAT)
emit("cvtsi2ss #eax, #xmm0");
else if (is_inttype(from) && to->kind == KIND_DOUBLE)
emit("cvtsi2sd #eax, #xmm0");
else if (from->kind == KIND_FLOAT && to->kind == KIND_DOUBLE)
emit("cvtps2pd #xmm0, #xmm0");
else if ((from->kind == KIND_DOUBLE || from->kind == KIND_LDOUBLE) && to->kind == KIND_FLOAT)
emit("cvtpd2ps #xmm0, #xmm0");
else if (to->kind == KIND_BOOL)
emit_to_bool(from);
else if (is_inttype(from) && is_inttype(to))
emit_intcast(from);
else if (is_inttype(to))
emit_toint(from);
}
static void emit_ret() {
SAVE;
emit("leave");
emit("ret");
}
static void emit_binop(Node *node) {
SAVE;
if (node->ty->kind == KIND_PTR) {
emit_pointer_arith(node->kind, node->left, node->right);
return;
}
switch (node->kind) {
case '<': emit_comp("setl", "setb", node); return;
case OP_EQ: emit_comp("sete", "sete", node); return;
case OP_LE: emit_comp("setle", "setna", node); return;
case OP_NE: emit_comp("setne", "setne", node); return;
}
if (is_inttype(node->ty))
emit_binop_int_arith(node);
else if (is_flotype(node->ty))
emit_binop_float_arith(node);
else
error("internal error: %s", node2s(node));
}
static void emit_save_literal(Node *node, Type *totype, int off) {
switch (totype->kind) {
case KIND_BOOL: emit("movb $%d, %d(#rbp)", !!node->ival, off); break;
case KIND_CHAR: emit("movb $%d, %d(#rbp)", node->ival, off); break;
case KIND_SHORT: emit("movw $%d, %d(#rbp)", node->ival, off); break;
case KIND_INT: emit("movl $%d, %d(#rbp)", node->ival, off); break;
case KIND_LONG:
case KIND_LLONG:
case KIND_PTR: {
emit("movl $%lu, %d(#rbp)", ((uint64_t)node->ival) & ((1L << 32) - 1), off);
emit("movl $%lu, %d(#rbp)", ((uint64_t)node->ival) >> 32, off + 4);
break;
}
case KIND_FLOAT: {
float fval = node->fval;
emit("movl $%u, %d(#rbp)", *(uint32_t *)&fval, off);
break;
}
case KIND_DOUBLE:
case KIND_LDOUBLE: {
emit("movl $%lu, %d(#rbp)", *(uint64_t *)&node->fval & ((1L << 32) - 1), off);
emit("movl $%lu, %d(#rbp)", *(uint64_t *)&node->fval >> 32, off + 4);
break;
}
default:
error("internal error: <%s> <%s> <%d>", node2s(node), ty2s(totype), off);
}
}
static void emit_addr(Node *node) {
switch (node->kind) {
case AST_LVAR:
ensure_lvar_init(node);
emit("lea %d(#rbp), #rax", node->loff);
break;
case AST_GVAR:
emit("lea %s(#rip), #rax", node->glabel);
break;
case AST_DEREF:
emit_expr(node->operand);
break;
case AST_STRUCT_REF:
emit_addr(node->struc);
emit("add $%d, #rax", node->ty->offset);
break;
case AST_FUNCDESG:
emit("lea %s(#rip), #rax", node->fname);
break;
default:
error("internal error: %s", node2s(node));
}
}
static void emit_copy_struct(Node *left, Node *right) {
push("rcx");
push("r11");
emit_addr(right);
emit("mov #rax, #rcx");
emit_addr(left);
int i = 0;
for (; i < left->ty->size; i += 8) {
emit("movq %d(#rcx), #r11", i);
emit("movq #r11, %d(#rax)", i);
}
for (; i < left->ty->size; i += 4) {
emit("movl %d(#rcx), #r11", i);
emit("movl #r11, %d(#rax)", i);
}
for (; i < left->ty->size; i++) {
emit("movb %d(#rcx), #r11", i);
emit("movb #r11, %d(#rax)", i);
}
pop("r11");
pop("rcx");
}
static int cmpinit(const void *x, const void *y) {
Node *a = *(Node **)x;
Node *b = *(Node **)y;
return a->initoff - b->initoff;
}
static void emit_fill_holes(Vector *inits, int off, int totalsize) {
// If at least one of the fields in a variable are initialized,
// unspecified fields has to be initialized with 0.
int len = vec_len(inits);
Node **buf = malloc(len * sizeof(Node *));
for (int i = 0; i < len; i++)
buf[i] = vec_get(inits, i);
qsort(buf, len, sizeof(Node *), cmpinit);
int lastend = 0;
for (int i = 0; i < len; i++) {
Node *node = buf[i];
if (lastend < node->initoff)
emit_zero_filler(lastend + off, node->initoff + off);
lastend = node->initoff + node->totype->size;
}
emit_zero_filler(lastend + off, totalsize + off);
}
static void emit_decl_init(Vector *inits, int off, int totalsize) {
emit_fill_holes(inits, off, totalsize);
for (int i = 0; i < vec_len(inits); i++) {
Node *node = vec_get(inits, i);
assert(node->kind == AST_INIT);
bool isbitfield = (node->totype->bitsize > 0);
if (node->initval->kind == AST_LITERAL && !isbitfield) {
emit_save_literal(node->initval, node->totype, node->initoff + off);
} else {
emit_expr(node->initval);
emit_lsave(node->totype, node->initoff + off);
}
}
}
static void emit_pre_inc_dec(Node *node, char *op) {
emit_expr(node->operand);
emit("%s $%d, #rax", op, node->ty->ptr ? node->ty->ptr->size : 1);
emit_store(node->operand);
}
static void emit_post_inc_dec(Node *node, char *op) {
SAVE;
emit_expr(node->operand);
push("rax");
emit("%s $%d, #rax", op, node->ty->ptr ? node->ty->ptr->size : 1);
emit_store(node->operand);
pop("rax");
}
static void set_reg_nums(Vector *args) {
numgp = numfp = 0;
for (int i = 0; i < vec_len(args); i++) {
Node *arg = vec_get(args, i);
if (is_flotype(arg->ty))
numfp++;
else
numgp++;
}
}
static void emit_je(char *label) {
emit("test #rax, #rax");
emit("je %s", label);
}
static void emit_label(char *label) {
emit("%s:", label);
}
static void emit_jmp(char *label) {
emit("jmp %s", label);
}
static void emit_literal(Node *node) {
SAVE;
switch (node->ty->kind) {
case KIND_BOOL:
case KIND_CHAR:
case KIND_SHORT:
emit("mov $%u, #rax", node->ival);
break;
case KIND_INT:
emit("mov $%u, #rax", node->ival);
break;
case KIND_LONG:
case KIND_LLONG: {
emit("mov $%lu, #rax", node->ival);
break;
}
case KIND_FLOAT: {
if (!node->flabel) {
node->flabel = make_label();
float fval = node->fval;
emit_noindent(".data");
emit_label(node->flabel);
emit(".long %d", *(uint32_t *)&fval);
emit_noindent(".text");
}
emit("movss %s(#rip), #xmm0", node->flabel);
break;
}
case KIND_DOUBLE:
case KIND_LDOUBLE: {
if (!node->flabel) {
node->flabel = make_label();
emit_noindent(".data");
emit_label(node->flabel);
emit(".quad %lu", *(uint64_t *)&node->fval);
emit_noindent(".text");
}
emit("movsd %s(#rip), #xmm0", node->flabel);
break;
}
case KIND_ARRAY: {
if (!node->slabel) {
node->slabel = make_label();
emit_noindent(".data");
emit_label(node->slabel);
emit(".string \"%s\"", quote_cstring_len(node->sval, node->ty->size - 1));
emit_noindent(".text");
}
emit("lea %s(#rip), #rax", node->slabel);
break;
}
default:
error("internal error");
}
}
static char **split(char *buf) {
char *p = buf;
int len = 1;
while (*p) {
if (p[0] == '\r' && p[1] == '\n') {
len++;
p += 2;
continue;
}
if (p[0] == '\r' || p[0] == '\n')
len++;
p++;
}
p = buf;
char **r = malloc(sizeof(char *) * len + 1);
int i = 0;
while (*p) {
if (p[0] == '\r' && p[1] == '\n') {
p[0] = '\0';
p += 2;
r[i++] = p;
continue;
}
if (p[0] == '\r' || p[0] == '\n') {
p[0] = '\0';
r[i++] = p + 1;
}
p++;
}
r[i] = NULL;
return r;
}
static char **read_source_file(char *file) {
FILE *fp = fopen(file, "r");
if (!fp)
return NULL;
struct stat st;
fstat(fileno(fp), &st);
char *buf = malloc(st.st_size + 1);
if (fread(buf, 1, st.st_size, fp) != st.st_size) {
fclose(fp);
return NULL;
}
fclose(fp);
buf[st.st_size] = '\0';
return split(buf);
}
static void maybe_print_source_line(char *file, int line) {
if (!dumpsource)
return;
char **lines = map_get(source_lines, file);
if (!lines) {
lines = read_source_file(file);
if (!lines)
return;
map_put(source_lines, file, lines);
}
int len = 0;
for (char **p = lines; *p; p++)
len++;
emit_nostack("# %s", lines[line - 1]);
}
static void maybe_print_source_loc(Node *node) {
if (!node->sourceLoc)
return;
char *file = node->sourceLoc->file;
long fileno = (long)map_get(source_files, file);
if (!fileno) {
fileno = map_len(source_files) + 1;
map_put(source_files, file, (void *)fileno);
emit(".file %ld \"%s\"", fileno, quote_cstring(file));
}
char *loc = format(".loc %ld %d 0", fileno, node->sourceLoc->line);
if (strcmp(loc, last_loc)) {
emit("%s", loc);
maybe_print_source_line(file, node->sourceLoc->line);
}
last_loc = loc;
}
static void emit_lvar(Node *node) {
SAVE;
ensure_lvar_init(node);
emit_lload(node->ty, "rbp", node->loff);
}
static void emit_gvar(Node *node) {
SAVE;
emit_gload(node->ty, node->glabel, 0);
}
static void emit_builtin_return_address(Node *node) {
push("r11");
assert(vec_len(node->args) == 1);
emit_expr(vec_head(node->args));
char *loop = make_label();
char *end = make_label();
emit("mov #rbp, #r11");
emit_label(loop);
emit("test #rax, #rax");
emit("jz %s", end);
emit("mov (#r11), #r11");
emit("sub $1, #rax");
emit_jmp(loop);
emit_label(end);
emit("mov 8(#r11), #rax");
pop("r11");
}
// Set the register class for parameter passing to RAX.
// 0 is INTEGER, 1 is SSE, 2 is MEMORY.
static void emit_builtin_reg_class(Node *node) {
Node *arg = vec_get(node->args, 0);
assert(arg->ty->kind == KIND_PTR);
Type *ty = arg->ty->ptr;
if (ty->kind == KIND_STRUCT)
emit("mov $2, #eax");
else if (is_flotype(ty))
emit("mov $1, #eax");
else
emit("mov $0, #eax");
}
static void emit_builtin_va_start(Node *node) {
SAVE;
assert(vec_len(node->args) == 1);
emit_expr(vec_head(node->args));
push("rcx");
emit("movl $%d, (#rax)", numgp * 8);
emit("movl $%d, 4(#rax)", 48 + numfp * 16);
emit("lea %d(#rbp), #rcx", -REGAREA_SIZE);
emit("mov #rcx, 16(#rax)");
pop("rcx");
}
static bool maybe_emit_builtin(Node *node) {
SAVE;
if (!strcmp("__builtin_return_address", node->fname)) {
emit_builtin_return_address(node);
return true;
}
if (!strcmp("__builtin_reg_class", node->fname)) {
emit_builtin_reg_class(node);
return true;
}
if (!strcmp("__builtin_va_start", node->fname)) {
emit_builtin_va_start(node);
return true;
}
return false;
}
static void classify_args(Vector *ints, Vector *floats, Vector *rest, Vector *args) {
SAVE;
int ireg = 0, xreg = 0;
int imax = 6, xmax = 8;
for (int i = 0; i < vec_len(args); i++) {
Node *v = vec_get(args, i);
if (v->ty->kind == KIND_STRUCT)
vec_push(rest, v);
else if (is_flotype(v->ty))
vec_push((xreg++ < xmax) ? floats : rest, v);
else
vec_push((ireg++ < imax) ? ints : rest, v);
}
}
static void save_arg_regs(int nints, int nfloats) {
SAVE;
assert(nints <= 6);
assert(nfloats <= 8);
for (int i = 0; i < nints; i++)
push(REGS[i]);
for (int i = 1; i < nfloats; i++)
push_xmm(i);
}
static void restore_arg_regs(int nints, int nfloats) {
SAVE;
for (int i = nfloats - 1; i > 0; i--)
pop_xmm(i);
for (int i = nints - 1; i >= 0; i--)
pop(REGS[i]);
}
static int emit_args(Vector *vals) {
SAVE;
int r = 0;
for (int i = 0; i < vec_len(vals); i++) {
Node *v = vec_get(vals, i);
if (v->ty->kind == KIND_STRUCT) {
emit_addr(v);
r += push_struct(v->ty->size);
} else if (is_flotype(v->ty)) {
emit_expr(v);
push_xmm(0);
r += 8;
} else {
emit_expr(v);
push("rax");
r += 8;
}
}
return r;
}
static void pop_int_args(int nints) {
SAVE;
for (int i = nints - 1; i >= 0; i--)
pop(REGS[i]);
}
static void pop_float_args(int nfloats) {
SAVE;
for (int i = nfloats - 1; i >= 0; i--)
pop_xmm(i);
}
static void maybe_booleanize_retval(Type *ty) {
if (ty->kind == KIND_BOOL) {
emit("movzx #al, #rax");
}
}
static void emit_func_call(Node *node) {