mikepaul-LuaJIT/src/buildvm_asm.c
Mike Pall 43f1e13470 Integrate MinGW build with DWARF2 exception handling.
Only works with DWARF2-enabled GCC 4.x (not the default MinGW GCC).
Fix fastcall symbol names for COFF assembler output.
Add DWARF2 unwind info to COFF assembler output.
Use COFF assembler mode for MinGW builds.
Always enable the DWARF2 handler if compiled with GCC.
2010-01-22 01:56:49 +01:00

235 lines
6.0 KiB
C

/*
** LuaJIT VM builder: Assembler source code emitter.
** Copyright (C) 2005-2010 Mike Pall. See Copyright Notice in luajit.h
*/
#include "buildvm.h"
#include "lj_bc.h"
/* ------------------------------------------------------------------------ */
/* Emit bytes piecewise as assembler text. */
static void emit_asm_bytes(BuildCtx *ctx, uint8_t *p, int n)
{
int i;
for (i = 0; i < n; i++) {
if ((i & 15) == 0)
fprintf(ctx->fp, "\t.byte %d", p[i]);
else
fprintf(ctx->fp, ",%d", p[i]);
if ((i & 15) == 15) putc('\n', ctx->fp);
}
if ((n & 15) != 0) putc('\n', ctx->fp);
}
/* Emit relocation */
static void emit_asm_reloc(BuildCtx *ctx, int type, const char *sym)
{
switch (ctx->mode) {
case BUILD_elfasm:
if (type)
fprintf(ctx->fp, "\t.long %s-.-4\n", sym);
else
fprintf(ctx->fp, "\t.long %s\n", sym);
break;
case BUILD_coffasm:
fprintf(ctx->fp, "\t.def %s; .scl 3; .type 32; .endef\n", sym);
if (type)
fprintf(ctx->fp, "\t.long %s-.-4\n", sym);
else
fprintf(ctx->fp, "\t.long %s\n", sym);
break;
default: /* BUILD_machasm for relative relocations handled below. */
fprintf(ctx->fp, "\t.long %s\n", sym);
break;
}
}
static const char *const jccnames[] = {
"jo", "jno", "jb", "jnb", "jz", "jnz", "jbe", "ja",
"js", "jns", "jpe", "jpo", "jl", "jge", "jle", "jg"
};
/* Emit relocation for the incredibly stupid OSX assembler. */
static void emit_asm_reloc_mach(BuildCtx *ctx, uint8_t *cp, int n,
const char *sym)
{
const char *opname = NULL;
if (--n < 0) goto err;
if (cp[n] == 0xe8) {
opname = "call";
} else if (cp[n] == 0xe9) {
opname = "jmp";
} else if (cp[n] >= 0x80 && cp[n] <= 0x8f && n > 0 && cp[n-1] == 0x0f) {
opname = jccnames[cp[n]-0x80];
n--;
} else {
err:
fprintf(stderr, "Error: unsupported opcode for %s symbol relocation.\n",
sym);
exit(1);
}
emit_asm_bytes(ctx, cp, n);
fprintf(ctx->fp, "\t%s %s\n", opname, sym);
}
/* Emit an assembler label. */
static void emit_asm_label(BuildCtx *ctx, const char *name, int size, int isfunc)
{
switch (ctx->mode) {
case BUILD_elfasm:
fprintf(ctx->fp,
"\n\t.globl %s\n"
"\t.hidden %s\n"
"\t.type %s, @%s\n"
"\t.size %s, %d\n"
"%s:\n",
name, name, name, isfunc ? "function" : "object", name, size, name);
break;
case BUILD_coffasm:
fprintf(ctx->fp, "\n\t.globl %s\n", name);
if (isfunc)
fprintf(ctx->fp, "\t.def %s; .scl 3; .type 32; .endef\n", name);
fprintf(ctx->fp, "%s:\n", name);
break;
case BUILD_machasm:
fprintf(ctx->fp,
"\n\t.private_extern %s\n"
"%s:\n", name, name);
break;
default:
break;
}
}
/* Emit alignment. */
static void emit_asm_align(BuildCtx *ctx, int bits)
{
switch (ctx->mode) {
case BUILD_elfasm:
case BUILD_coffasm:
fprintf(ctx->fp, "\t.p2align %d\n", bits);
break;
case BUILD_machasm:
fprintf(ctx->fp, "\t.align %d\n", bits);
break;
default:
break;
}
}
/* ------------------------------------------------------------------------ */
/* Emit assembler source code. */
void emit_asm(BuildCtx *ctx)
{
char name[80];
int32_t prev;
int i, pi, rel;
#if LJ_64
const char *symprefix = ctx->mode == BUILD_machasm ? "_" : "";
int keepfc = 0;
#else
const char *symprefix = ctx->mode != BUILD_elfasm ? "_" : "";
/* Keep fastcall suffix for COFF on WIN32. */
int keepfc = (ctx->mode == BUILD_coffasm);
#endif
fprintf(ctx->fp, "\t.file \"buildvm_%s.dasc\"\n", ctx->dasm_arch);
fprintf(ctx->fp, "\t.text\n");
emit_asm_align(ctx, 4);
sprintf(name, "%s" LABEL_ASM_BEGIN, symprefix);
emit_asm_label(ctx, name, 0, 0);
if (ctx->mode != BUILD_machasm)
fprintf(ctx->fp, ".Lbegin:\n");
i = 0;
do {
pi = ctx->perm[i++];
prev = ctx->sym_ofs[pi];
} while (prev < 0); /* Skip the _Z symbols. */
for (rel = 0; i <= ctx->nsym; i++) {
int ni = ctx->perm[i];
int32_t next = ctx->sym_ofs[ni];
int size = (int)(next - prev);
int32_t stop = next;
if (pi >= ctx->npc) {
char *p;
sprintf(name, "%s" LABEL_PREFIX "%s", symprefix,
ctx->globnames[pi-ctx->npc]);
p = strchr(name, '@');
if (p) { if (keepfc) name[0] = '@'; else *p = '\0'; }
emit_asm_label(ctx, name, size, 1);
#if LJ_HASJIT
} else {
#else
} else if (!(pi == BC_JFORI || pi == BC_JFORL || pi == BC_JITERL ||
pi == BC_JLOOP || pi == BC_IFORL || pi == BC_IITERL ||
pi == BC_ILOOP)) {
#endif
sprintf(name, "%s" LABEL_PREFIX_BC "%s", symprefix, bc_names[pi]);
emit_asm_label(ctx, name, size, 1);
}
while (rel < ctx->nreloc && ctx->reloc[rel].ofs < stop) {
BuildReloc *r = &ctx->reloc[rel];
int n = r->ofs - prev;
char *p;
sprintf(name, "%s%s", symprefix, ctx->extnames[r->sym]);
p = strchr(name, '@');
if (p) { if (keepfc) name[0] = '@'; else *p = '\0'; }
if (ctx->mode == BUILD_machasm && r->type != 0) {
emit_asm_reloc_mach(ctx, ctx->code+prev, n, name);
} else {
emit_asm_bytes(ctx, ctx->code+prev, n);
emit_asm_reloc(ctx, r->type, name);
}
prev += n+4;
rel++;
}
emit_asm_bytes(ctx, ctx->code+prev, stop-prev);
prev = next;
pi = ni;
}
switch (ctx->mode) {
case BUILD_elfasm:
fprintf(ctx->fp, "\n\t.section .rodata\n");
break;
case BUILD_coffasm:
fprintf(ctx->fp, "\n\t.section .rdata,\"dr\"\n");
break;
case BUILD_machasm:
fprintf(ctx->fp, "\n\t.const\n");
break;
default:
break;
}
emit_asm_align(ctx, 5);
sprintf(name, "%s" LABEL_OP_OFS, symprefix);
emit_asm_label(ctx, name, 2*ctx->npc, 0);
for (i = 0; i < ctx->npc; i++)
fprintf(ctx->fp, "\t.short %d\n", ctx->sym_ofs[i]);
fprintf(ctx->fp, "\n");
switch (ctx->mode) {
case BUILD_elfasm:
fprintf(ctx->fp, "\t.section .note.GNU-stack,\"\",@progbits\n");
/* fallthrough */
case BUILD_coffasm:
fprintf(ctx->fp, "\t.ident \"%s\"\n", ctx->dasm_ident);
break;
case BUILD_machasm:
fprintf(ctx->fp,
"\t.cstring\n"
"\t.ascii \"%s\\0\"\n", ctx->dasm_ident);
break;
default:
break;
}
fprintf(ctx->fp, "\n");
}