tccasm: synch C and asm symtab tighter
[tinycc.git] / i386-gen.c
blobb9c3599fd8fc4157f8281bd20484e5867e8fd4c5
1 /*
2 * X86 code generator for TCC
3 *
4 * Copyright (c) 2001-2004 Fabrice Bellard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #ifdef TARGET_DEFS_ONLY
23 /* number of available registers */
24 #define NB_REGS 5
25 #define NB_ASM_REGS 8
26 #define CONFIG_TCC_ASM
28 /* a register can belong to several classes. The classes must be
29 sorted from more general to more precise (see gv2() code which does
30 assumptions on it). */
31 #define RC_INT 0x0001 /* generic integer register */
32 #define RC_FLOAT 0x0002 /* generic float register */
33 #define RC_EAX 0x0004
34 #define RC_ST0 0x0008
35 #define RC_ECX 0x0010
36 #define RC_EDX 0x0020
37 #define RC_EBX 0x0040
39 #define RC_IRET RC_EAX /* function return: integer register */
40 #define RC_LRET RC_EDX /* function return: second integer register */
41 #define RC_FRET RC_ST0 /* function return: float register */
43 /* pretty names for the registers */
44 enum {
45 TREG_EAX = 0,
46 TREG_ECX,
47 TREG_EDX,
48 TREG_EBX,
49 TREG_ST0,
50 TREG_ESP = 4
53 /* return registers for function */
54 #define REG_IRET TREG_EAX /* single word int return register */
55 #define REG_LRET TREG_EDX /* second word return register (for long long) */
56 #define REG_FRET TREG_ST0 /* float return register */
58 /* defined if function parameters must be evaluated in reverse order */
59 #define INVERT_FUNC_PARAMS
61 /* defined if structures are passed as pointers. Otherwise structures
62 are directly pushed on stack. */
63 /* #define FUNC_STRUCT_PARAM_AS_PTR */
65 /* pointer size, in bytes */
66 #define PTR_SIZE 4
68 /* long double size and alignment, in bytes */
69 #define LDOUBLE_SIZE 12
70 #define LDOUBLE_ALIGN 4
71 /* maximum alignment (for aligned attribute support) */
72 #define MAX_ALIGN 8
74 /******************************************************/
75 #else /* ! TARGET_DEFS_ONLY */
76 /******************************************************/
77 #include "tcc.h"
79 /* define to 1/0 to [not] have EBX as 4th register */
80 #define USE_EBX 0
82 ST_DATA const int reg_classes[NB_REGS] = {
83 /* eax */ RC_INT | RC_EAX,
84 /* ecx */ RC_INT | RC_ECX,
85 /* edx */ RC_INT | RC_EDX,
86 /* ebx */ (RC_INT | RC_EBX) * USE_EBX,
87 /* st0 */ RC_FLOAT | RC_ST0,
90 static unsigned long func_sub_sp_offset;
91 static int func_ret_sub;
92 #ifdef CONFIG_TCC_BCHECK
93 static addr_t func_bound_offset;
94 static unsigned long func_bound_ind;
95 #endif
97 /* XXX: make it faster ? */
98 ST_FUNC void g(int c)
100 int ind1;
101 if (nocode_wanted)
102 return;
103 ind1 = ind + 1;
104 if (ind1 > cur_text_section->data_allocated)
105 section_realloc(cur_text_section, ind1);
106 cur_text_section->data[ind] = c;
107 ind = ind1;
110 ST_FUNC void o(unsigned int c)
112 while (c) {
113 g(c);
114 c = c >> 8;
118 ST_FUNC void gen_le16(int v)
120 g(v);
121 g(v >> 8);
124 ST_FUNC void gen_le32(int c)
126 g(c);
127 g(c >> 8);
128 g(c >> 16);
129 g(c >> 24);
132 /* output a symbol and patch all calls to it */
133 ST_FUNC void gsym_addr(int t, int a)
135 while (t) {
136 unsigned char *ptr = cur_text_section->data + t;
137 uint32_t n = read32le(ptr); /* next value */
138 write32le(ptr, a - t - 4);
139 t = n;
143 ST_FUNC void gsym(int t)
145 gsym_addr(t, ind);
148 /* instruction + 4 bytes data. Return the address of the data */
149 static int oad(int c, int s)
151 int t;
152 if (nocode_wanted)
153 return s;
154 o(c);
155 t = ind;
156 gen_le32(s);
157 return t;
160 /* generate jmp to a label */
161 #define gjmp2(instr,lbl) oad(instr,lbl)
163 /* output constant with relocation if 'r & VT_SYM' is true */
164 ST_FUNC void gen_addr32(int r, Sym *sym, int c)
166 if (r & VT_SYM)
167 greloc(cur_text_section, sym, ind, R_386_32);
168 gen_le32(c);
171 ST_FUNC void gen_addrpc32(int r, Sym *sym, int c)
173 if (r & VT_SYM)
174 greloc(cur_text_section, sym, ind, R_386_PC32);
175 gen_le32(c - 4);
178 /* generate a modrm reference. 'op_reg' contains the additional 3
179 opcode bits */
180 static void gen_modrm(int op_reg, int r, Sym *sym, int c)
182 op_reg = op_reg << 3;
183 if ((r & VT_VALMASK) == VT_CONST) {
184 /* constant memory reference */
185 o(0x05 | op_reg);
186 gen_addr32(r, sym, c);
187 } else if ((r & VT_VALMASK) == VT_LOCAL) {
188 /* currently, we use only ebp as base */
189 if (c == (char)c) {
190 /* short reference */
191 o(0x45 | op_reg);
192 g(c);
193 } else {
194 oad(0x85 | op_reg, c);
196 } else {
197 g(0x00 | op_reg | (r & VT_VALMASK));
201 /* load 'r' from value 'sv' */
202 ST_FUNC void load(int r, SValue *sv)
204 int v, t, ft, fc, fr;
205 SValue v1;
207 #ifdef TCC_TARGET_PE
208 SValue v2;
209 sv = pe_getimport(sv, &v2);
210 #endif
212 fr = sv->r;
213 ft = sv->type.t & ~VT_DEFSIGN;
214 fc = sv->c.i;
216 ft &= ~(VT_VOLATILE | VT_CONSTANT);
218 v = fr & VT_VALMASK;
219 if (fr & VT_LVAL) {
220 if (v == VT_LLOCAL) {
221 v1.type.t = VT_INT;
222 v1.r = VT_LOCAL | VT_LVAL;
223 v1.c.i = fc;
224 fr = r;
225 if (!(reg_classes[fr] & RC_INT))
226 fr = get_reg(RC_INT);
227 load(fr, &v1);
229 if ((ft & VT_BTYPE) == VT_FLOAT) {
230 o(0xd9); /* flds */
231 r = 0;
232 } else if ((ft & VT_BTYPE) == VT_DOUBLE) {
233 o(0xdd); /* fldl */
234 r = 0;
235 } else if ((ft & VT_BTYPE) == VT_LDOUBLE) {
236 o(0xdb); /* fldt */
237 r = 5;
238 } else if ((ft & VT_TYPE) == VT_BYTE || (ft & VT_TYPE) == VT_BOOL) {
239 o(0xbe0f); /* movsbl */
240 } else if ((ft & VT_TYPE) == (VT_BYTE | VT_UNSIGNED)) {
241 o(0xb60f); /* movzbl */
242 } else if ((ft & VT_TYPE) == VT_SHORT) {
243 o(0xbf0f); /* movswl */
244 } else if ((ft & VT_TYPE) == (VT_SHORT | VT_UNSIGNED)) {
245 o(0xb70f); /* movzwl */
246 } else {
247 o(0x8b); /* movl */
249 gen_modrm(r, fr, sv->sym, fc);
250 } else {
251 if (v == VT_CONST) {
252 o(0xb8 + r); /* mov $xx, r */
253 gen_addr32(fr, sv->sym, fc);
254 } else if (v == VT_LOCAL) {
255 if (fc) {
256 o(0x8d); /* lea xxx(%ebp), r */
257 gen_modrm(r, VT_LOCAL, sv->sym, fc);
258 } else {
259 o(0x89);
260 o(0xe8 + r); /* mov %ebp, r */
262 } else if (v == VT_CMP) {
263 oad(0xb8 + r, 0); /* mov $0, r */
264 o(0x0f); /* setxx %br */
265 o(fc);
266 o(0xc0 + r);
267 } else if (v == VT_JMP || v == VT_JMPI) {
268 t = v & 1;
269 oad(0xb8 + r, t); /* mov $1, r */
270 o(0x05eb); /* jmp after */
271 gsym(fc);
272 oad(0xb8 + r, t ^ 1); /* mov $0, r */
273 } else if (v != r) {
274 o(0x89);
275 o(0xc0 + r + v * 8); /* mov v, r */
280 /* store register 'r' in lvalue 'v' */
281 ST_FUNC void store(int r, SValue *v)
283 int fr, bt, ft, fc;
285 #ifdef TCC_TARGET_PE
286 SValue v2;
287 v = pe_getimport(v, &v2);
288 #endif
290 ft = v->type.t;
291 fc = v->c.i;
292 fr = v->r & VT_VALMASK;
293 ft &= ~(VT_VOLATILE | VT_CONSTANT);
294 bt = ft & VT_BTYPE;
295 /* XXX: incorrect if float reg to reg */
296 if (bt == VT_FLOAT) {
297 o(0xd9); /* fsts */
298 r = 2;
299 } else if (bt == VT_DOUBLE) {
300 o(0xdd); /* fstpl */
301 r = 2;
302 } else if (bt == VT_LDOUBLE) {
303 o(0xc0d9); /* fld %st(0) */
304 o(0xdb); /* fstpt */
305 r = 7;
306 } else {
307 if (bt == VT_SHORT)
308 o(0x66);
309 if (bt == VT_BYTE || bt == VT_BOOL)
310 o(0x88);
311 else
312 o(0x89);
314 if (fr == VT_CONST ||
315 fr == VT_LOCAL ||
316 (v->r & VT_LVAL)) {
317 gen_modrm(r, v->r, v->sym, fc);
318 } else if (fr != r) {
319 o(0xc0 + fr + r * 8); /* mov r, fr */
323 static void gadd_sp(int val)
325 if (val == (char)val) {
326 o(0xc483);
327 g(val);
328 } else {
329 oad(0xc481, val); /* add $xxx, %esp */
333 #if defined CONFIG_TCC_BCHECK || defined TCC_TARGET_PE
334 static void gen_static_call(int v)
336 Sym *sym;
338 sym = external_global_sym(v, &func_old_type, 0);
339 oad(0xe8, -4);
340 greloc(cur_text_section, sym, ind-4, R_386_PC32);
342 #endif
344 /* 'is_jmp' is '1' if it is a jump */
345 static void gcall_or_jmp(int is_jmp)
347 int r;
348 if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST && (vtop->r & VT_SYM)) {
349 /* constant and relocation case */
350 greloc(cur_text_section, vtop->sym, ind + 1, R_386_PC32);
351 oad(0xe8 + is_jmp, vtop->c.i - 4); /* call/jmp im */
352 } else {
353 /* otherwise, indirect call */
354 r = gv(RC_INT);
355 o(0xff); /* call/jmp *r */
356 o(0xd0 + r + (is_jmp << 4));
358 if (!is_jmp) {
359 int rt;
360 /* extend the return value to the whole register if necessary
361 visual studio and gcc do not always set the whole eax register
362 when assigning the return value of a function */
363 rt = vtop->type.ref->type.t;
364 switch (rt & VT_BTYPE) {
365 case VT_BYTE:
366 if (rt & VT_UNSIGNED) {
367 o(0xc0b60f); /* movzx %al, %eax */
369 else {
370 o(0xc0be0f); /* movsx %al, %eax */
372 break;
373 case VT_SHORT:
374 if (rt & VT_UNSIGNED) {
375 o(0xc0b70f); /* movzx %ax, %eax */
377 else {
378 o(0xc0bf0f); /* movsx %ax, %eax */
380 break;
381 default:
382 break;
387 static uint8_t fastcall_regs[3] = { TREG_EAX, TREG_EDX, TREG_ECX };
388 static uint8_t fastcallw_regs[2] = { TREG_ECX, TREG_EDX };
390 /* Return the number of registers needed to return the struct, or 0 if
391 returning via struct pointer. */
392 ST_FUNC int gfunc_sret(CType *vt, int variadic, CType *ret, int *ret_align, int *regsize)
394 #ifdef TCC_TARGET_PE
395 int size, align;
396 *ret_align = 1; // Never have to re-align return values for x86
397 *regsize = 4;
398 size = type_size(vt, &align);
399 if (size > 8 || (size & (size - 1)))
400 return 0;
401 if (size == 8)
402 ret->t = VT_LLONG;
403 else if (size == 4)
404 ret->t = VT_INT;
405 else if (size == 2)
406 ret->t = VT_SHORT;
407 else
408 ret->t = VT_BYTE;
409 ret->ref = NULL;
410 return 1;
411 #else
412 *ret_align = 1; // Never have to re-align return values for x86
413 return 0;
414 #endif
417 /* Generate function call. The function address is pushed first, then
418 all the parameters in call order. This functions pops all the
419 parameters and the function address. */
420 ST_FUNC void gfunc_call(int nb_args)
422 int size, align, r, args_size, i, func_call;
423 Sym *func_sym;
425 args_size = 0;
426 for(i = 0;i < nb_args; i++) {
427 if ((vtop->type.t & VT_BTYPE) == VT_STRUCT) {
428 size = type_size(&vtop->type, &align);
429 /* align to stack align size */
430 size = (size + 3) & ~3;
431 /* allocate the necessary size on stack */
432 oad(0xec81, size); /* sub $xxx, %esp */
433 /* generate structure store */
434 r = get_reg(RC_INT);
435 o(0x89); /* mov %esp, r */
436 o(0xe0 + r);
437 vset(&vtop->type, r | VT_LVAL, 0);
438 vswap();
439 vstore();
440 args_size += size;
441 } else if (is_float(vtop->type.t)) {
442 gv(RC_FLOAT); /* only one float register */
443 if ((vtop->type.t & VT_BTYPE) == VT_FLOAT)
444 size = 4;
445 else if ((vtop->type.t & VT_BTYPE) == VT_DOUBLE)
446 size = 8;
447 else
448 size = 12;
449 oad(0xec81, size); /* sub $xxx, %esp */
450 if (size == 12)
451 o(0x7cdb);
452 else
453 o(0x5cd9 + size - 4); /* fstp[s|l] 0(%esp) */
454 g(0x24);
455 g(0x00);
456 args_size += size;
457 } else {
458 /* simple type (currently always same size) */
459 /* XXX: implicit cast ? */
460 r = gv(RC_INT);
461 if ((vtop->type.t & VT_BTYPE) == VT_LLONG) {
462 size = 8;
463 o(0x50 + vtop->r2); /* push r */
464 } else {
465 size = 4;
467 o(0x50 + r); /* push r */
468 args_size += size;
470 vtop--;
472 save_regs(0); /* save used temporary registers */
473 func_sym = vtop->type.ref;
474 func_call = func_sym->f.func_call;
475 /* fast call case */
476 if ((func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) ||
477 func_call == FUNC_FASTCALLW) {
478 int fastcall_nb_regs;
479 uint8_t *fastcall_regs_ptr;
480 if (func_call == FUNC_FASTCALLW) {
481 fastcall_regs_ptr = fastcallw_regs;
482 fastcall_nb_regs = 2;
483 } else {
484 fastcall_regs_ptr = fastcall_regs;
485 fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
487 for(i = 0;i < fastcall_nb_regs; i++) {
488 if (args_size <= 0)
489 break;
490 o(0x58 + fastcall_regs_ptr[i]); /* pop r */
491 /* XXX: incorrect for struct/floats */
492 args_size -= 4;
495 #ifndef TCC_TARGET_PE
496 else if ((vtop->type.ref->type.t & VT_BTYPE) == VT_STRUCT)
497 args_size -= 4;
498 #endif
499 gcall_or_jmp(0);
501 if (args_size && func_call != FUNC_STDCALL && func_call != FUNC_FASTCALLW)
502 gadd_sp(args_size);
503 vtop--;
506 #ifdef TCC_TARGET_PE
507 #define FUNC_PROLOG_SIZE (10 + USE_EBX)
508 #else
509 #define FUNC_PROLOG_SIZE (9 + USE_EBX)
510 #endif
512 /* generate function prolog of type 't' */
513 ST_FUNC void gfunc_prolog(CType *func_type)
515 int addr, align, size, func_call, fastcall_nb_regs;
516 int param_index, param_addr;
517 uint8_t *fastcall_regs_ptr;
518 Sym *sym;
519 CType *type;
521 sym = func_type->ref;
522 func_call = sym->f.func_call;
523 addr = 8;
524 loc = 0;
525 func_vc = 0;
527 if (func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) {
528 fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
529 fastcall_regs_ptr = fastcall_regs;
530 } else if (func_call == FUNC_FASTCALLW) {
531 fastcall_nb_regs = 2;
532 fastcall_regs_ptr = fastcallw_regs;
533 } else {
534 fastcall_nb_regs = 0;
535 fastcall_regs_ptr = NULL;
537 param_index = 0;
539 ind += FUNC_PROLOG_SIZE;
540 func_sub_sp_offset = ind;
541 /* if the function returns a structure, then add an
542 implicit pointer parameter */
543 func_vt = sym->type;
544 func_var = (sym->f.func_type == FUNC_ELLIPSIS);
545 #ifdef TCC_TARGET_PE
546 size = type_size(&func_vt,&align);
547 if (((func_vt.t & VT_BTYPE) == VT_STRUCT)
548 && (size > 8 || (size & (size - 1)))) {
549 #else
550 if ((func_vt.t & VT_BTYPE) == VT_STRUCT) {
551 #endif
552 /* XXX: fastcall case ? */
553 func_vc = addr;
554 addr += 4;
555 param_index++;
557 /* define parameters */
558 while ((sym = sym->next) != NULL) {
559 type = &sym->type;
560 size = type_size(type, &align);
561 size = (size + 3) & ~3;
562 #ifdef FUNC_STRUCT_PARAM_AS_PTR
563 /* structs are passed as pointer */
564 if ((type->t & VT_BTYPE) == VT_STRUCT) {
565 size = 4;
567 #endif
568 if (param_index < fastcall_nb_regs) {
569 /* save FASTCALL register */
570 loc -= 4;
571 o(0x89); /* movl */
572 gen_modrm(fastcall_regs_ptr[param_index], VT_LOCAL, NULL, loc);
573 param_addr = loc;
574 } else {
575 param_addr = addr;
576 addr += size;
578 sym_push(sym->v & ~SYM_FIELD, type,
579 VT_LOCAL | lvalue_type(type->t), param_addr);
580 param_index++;
582 func_ret_sub = 0;
583 /* pascal type call or fastcall ? */
584 if (func_call == FUNC_STDCALL || func_call == FUNC_FASTCALLW)
585 func_ret_sub = addr - 8;
586 #ifndef TCC_TARGET_PE
587 else if (func_vc)
588 func_ret_sub = 4;
589 #endif
591 #ifdef CONFIG_TCC_BCHECK
592 /* leave some room for bound checking code */
593 if (tcc_state->do_bounds_check) {
594 func_bound_offset = lbounds_section->data_offset;
595 func_bound_ind = ind;
596 oad(0xb8, 0); /* lbound section pointer */
597 oad(0xb8, 0); /* call to function */
599 #endif
602 /* generate function epilog */
603 ST_FUNC void gfunc_epilog(void)
605 addr_t v, saved_ind;
607 #ifdef CONFIG_TCC_BCHECK
608 if (tcc_state->do_bounds_check
609 && func_bound_offset != lbounds_section->data_offset) {
610 addr_t saved_ind;
611 addr_t *bounds_ptr;
612 Sym *sym_data;
614 /* add end of table info */
615 bounds_ptr = section_ptr_add(lbounds_section, sizeof(addr_t));
616 *bounds_ptr = 0;
618 /* generate bound local allocation */
619 saved_ind = ind;
620 ind = func_bound_ind;
621 sym_data = get_sym_ref(&char_pointer_type, lbounds_section,
622 func_bound_offset, lbounds_section->data_offset);
623 greloc(cur_text_section, sym_data,
624 ind + 1, R_386_32);
625 oad(0xb8, 0); /* mov %eax, xxx */
626 gen_static_call(TOK___bound_local_new);
627 ind = saved_ind;
629 /* generate bound check local freeing */
630 o(0x5250); /* save returned value, if any */
631 greloc(cur_text_section, sym_data, ind + 1, R_386_32);
632 oad(0xb8, 0); /* mov %eax, xxx */
633 gen_static_call(TOK___bound_local_delete);
634 o(0x585a); /* restore returned value, if any */
636 #endif
638 /* align local size to word & save local variables */
639 v = (-loc + 3) & -4;
641 #if USE_EBX
642 o(0x8b);
643 gen_modrm(TREG_EBX, VT_LOCAL, NULL, -(v+4));
644 #endif
646 o(0xc9); /* leave */
647 if (func_ret_sub == 0) {
648 o(0xc3); /* ret */
649 } else {
650 o(0xc2); /* ret n */
651 g(func_ret_sub);
652 g(func_ret_sub >> 8);
654 saved_ind = ind;
655 ind = func_sub_sp_offset - FUNC_PROLOG_SIZE;
656 #ifdef TCC_TARGET_PE
657 if (v >= 4096) {
658 oad(0xb8, v); /* mov stacksize, %eax */
659 gen_static_call(TOK___chkstk); /* call __chkstk, (does the stackframe too) */
660 } else
661 #endif
663 o(0xe58955); /* push %ebp, mov %esp, %ebp */
664 o(0xec81); /* sub esp, stacksize */
665 gen_le32(v);
666 #ifdef TCC_TARGET_PE
667 o(0x90); /* adjust to FUNC_PROLOG_SIZE */
668 #endif
670 o(0x53 * USE_EBX); /* push ebx */
671 ind = saved_ind;
674 /* generate a jump to a label */
675 ST_FUNC int gjmp(int t)
677 return gjmp2(0xe9, t);
680 /* generate a jump to a fixed address */
681 ST_FUNC void gjmp_addr(int a)
683 int r;
684 r = a - ind - 2;
685 if (r == (char)r) {
686 g(0xeb);
687 g(r);
688 } else {
689 oad(0xe9, a - ind - 5);
693 ST_FUNC void gtst_addr(int inv, int a)
695 int v = vtop->r & VT_VALMASK;
696 if (v == VT_CMP) {
697 inv ^= (vtop--)->c.i;
698 a -= ind + 2;
699 if (a == (char)a) {
700 g(inv - 32);
701 g(a);
702 } else {
703 g(0x0f);
704 oad(inv - 16, a - 4);
706 } else if ((v & ~1) == VT_JMP) {
707 if ((v & 1) != inv) {
708 gjmp_addr(a);
709 gsym(vtop->c.i);
710 } else {
711 gsym(vtop->c.i);
712 o(0x05eb);
713 gjmp_addr(a);
715 vtop--;
719 /* generate a test. set 'inv' to invert test. Stack entry is popped */
720 ST_FUNC int gtst(int inv, int t)
722 int v = vtop->r & VT_VALMASK;
723 if (nocode_wanted) {
725 } else if (v == VT_CMP) {
726 /* fast case : can jump directly since flags are set */
727 g(0x0f);
728 t = gjmp2((vtop->c.i - 16) ^ inv, t);
729 } else if (v == VT_JMP || v == VT_JMPI) {
730 /* && or || optimization */
731 if ((v & 1) == inv) {
732 /* insert vtop->c jump list in t */
733 uint32_t n1, n = vtop->c.i;
734 if (n) {
735 while ((n1 = read32le(cur_text_section->data + n)))
736 n = n1;
737 write32le(cur_text_section->data + n, t);
738 t = vtop->c.i;
740 } else {
741 t = gjmp(t);
742 gsym(vtop->c.i);
745 vtop--;
746 return t;
749 /* generate an integer binary operation */
750 ST_FUNC void gen_opi(int op)
752 int r, fr, opc, c;
754 switch(op) {
755 case '+':
756 case TOK_ADDC1: /* add with carry generation */
757 opc = 0;
758 gen_op8:
759 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
760 /* constant case */
761 vswap();
762 r = gv(RC_INT);
763 vswap();
764 c = vtop->c.i;
765 if (c == (char)c) {
766 /* generate inc and dec for smaller code */
767 if (c==1 && opc==0 && op != TOK_ADDC1) {
768 o (0x40 | r); // inc
769 } else if (c==1 && opc==5 && op != TOK_SUBC1) {
770 o (0x48 | r); // dec
771 } else {
772 o(0x83);
773 o(0xc0 | (opc << 3) | r);
774 g(c);
776 } else {
777 o(0x81);
778 oad(0xc0 | (opc << 3) | r, c);
780 } else {
781 gv2(RC_INT, RC_INT);
782 r = vtop[-1].r;
783 fr = vtop[0].r;
784 o((opc << 3) | 0x01);
785 o(0xc0 + r + fr * 8);
787 vtop--;
788 if (op >= TOK_ULT && op <= TOK_GT) {
789 vtop->r = VT_CMP;
790 vtop->c.i = op;
792 break;
793 case '-':
794 case TOK_SUBC1: /* sub with carry generation */
795 opc = 5;
796 goto gen_op8;
797 case TOK_ADDC2: /* add with carry use */
798 opc = 2;
799 goto gen_op8;
800 case TOK_SUBC2: /* sub with carry use */
801 opc = 3;
802 goto gen_op8;
803 case '&':
804 opc = 4;
805 goto gen_op8;
806 case '^':
807 opc = 6;
808 goto gen_op8;
809 case '|':
810 opc = 1;
811 goto gen_op8;
812 case '*':
813 gv2(RC_INT, RC_INT);
814 r = vtop[-1].r;
815 fr = vtop[0].r;
816 vtop--;
817 o(0xaf0f); /* imul fr, r */
818 o(0xc0 + fr + r * 8);
819 break;
820 case TOK_SHL:
821 opc = 4;
822 goto gen_shift;
823 case TOK_SHR:
824 opc = 5;
825 goto gen_shift;
826 case TOK_SAR:
827 opc = 7;
828 gen_shift:
829 opc = 0xc0 | (opc << 3);
830 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
831 /* constant case */
832 vswap();
833 r = gv(RC_INT);
834 vswap();
835 c = vtop->c.i & 0x1f;
836 o(0xc1); /* shl/shr/sar $xxx, r */
837 o(opc | r);
838 g(c);
839 } else {
840 /* we generate the shift in ecx */
841 gv2(RC_INT, RC_ECX);
842 r = vtop[-1].r;
843 o(0xd3); /* shl/shr/sar %cl, r */
844 o(opc | r);
846 vtop--;
847 break;
848 case '/':
849 case TOK_UDIV:
850 case TOK_PDIV:
851 case '%':
852 case TOK_UMOD:
853 case TOK_UMULL:
854 /* first operand must be in eax */
855 /* XXX: need better constraint for second operand */
856 gv2(RC_EAX, RC_ECX);
857 r = vtop[-1].r;
858 fr = vtop[0].r;
859 vtop--;
860 save_reg(TREG_EDX);
861 /* save EAX too if used otherwise */
862 save_reg_upstack(TREG_EAX, 1);
863 if (op == TOK_UMULL) {
864 o(0xf7); /* mul fr */
865 o(0xe0 + fr);
866 vtop->r2 = TREG_EDX;
867 r = TREG_EAX;
868 } else {
869 if (op == TOK_UDIV || op == TOK_UMOD) {
870 o(0xf7d231); /* xor %edx, %edx, div fr, %eax */
871 o(0xf0 + fr);
872 } else {
873 o(0xf799); /* cltd, idiv fr, %eax */
874 o(0xf8 + fr);
876 if (op == '%' || op == TOK_UMOD)
877 r = TREG_EDX;
878 else
879 r = TREG_EAX;
881 vtop->r = r;
882 break;
883 default:
884 opc = 7;
885 goto gen_op8;
889 /* generate a floating point operation 'v = t1 op t2' instruction. The
890 two operands are guaranteed to have the same floating point type */
891 /* XXX: need to use ST1 too */
892 ST_FUNC void gen_opf(int op)
894 int a, ft, fc, swapped, r;
896 /* convert constants to memory references */
897 if ((vtop[-1].r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
898 vswap();
899 gv(RC_FLOAT);
900 vswap();
902 if ((vtop[0].r & (VT_VALMASK | VT_LVAL)) == VT_CONST)
903 gv(RC_FLOAT);
905 /* must put at least one value in the floating point register */
906 if ((vtop[-1].r & VT_LVAL) &&
907 (vtop[0].r & VT_LVAL)) {
908 vswap();
909 gv(RC_FLOAT);
910 vswap();
912 swapped = 0;
913 /* swap the stack if needed so that t1 is the register and t2 is
914 the memory reference */
915 if (vtop[-1].r & VT_LVAL) {
916 vswap();
917 swapped = 1;
919 if (op >= TOK_ULT && op <= TOK_GT) {
920 /* load on stack second operand */
921 load(TREG_ST0, vtop);
922 save_reg(TREG_EAX); /* eax is used by FP comparison code */
923 if (op == TOK_GE || op == TOK_GT)
924 swapped = !swapped;
925 else if (op == TOK_EQ || op == TOK_NE)
926 swapped = 0;
927 if (swapped)
928 o(0xc9d9); /* fxch %st(1) */
929 if (op == TOK_EQ || op == TOK_NE)
930 o(0xe9da); /* fucompp */
931 else
932 o(0xd9de); /* fcompp */
933 o(0xe0df); /* fnstsw %ax */
934 if (op == TOK_EQ) {
935 o(0x45e480); /* and $0x45, %ah */
936 o(0x40fC80); /* cmp $0x40, %ah */
937 } else if (op == TOK_NE) {
938 o(0x45e480); /* and $0x45, %ah */
939 o(0x40f480); /* xor $0x40, %ah */
940 op = TOK_NE;
941 } else if (op == TOK_GE || op == TOK_LE) {
942 o(0x05c4f6); /* test $0x05, %ah */
943 op = TOK_EQ;
944 } else {
945 o(0x45c4f6); /* test $0x45, %ah */
946 op = TOK_EQ;
948 vtop--;
949 vtop->r = VT_CMP;
950 vtop->c.i = op;
951 } else {
952 /* no memory reference possible for long double operations */
953 if ((vtop->type.t & VT_BTYPE) == VT_LDOUBLE) {
954 load(TREG_ST0, vtop);
955 swapped = !swapped;
958 switch(op) {
959 default:
960 case '+':
961 a = 0;
962 break;
963 case '-':
964 a = 4;
965 if (swapped)
966 a++;
967 break;
968 case '*':
969 a = 1;
970 break;
971 case '/':
972 a = 6;
973 if (swapped)
974 a++;
975 break;
977 ft = vtop->type.t;
978 fc = vtop->c.i;
979 if ((ft & VT_BTYPE) == VT_LDOUBLE) {
980 o(0xde); /* fxxxp %st, %st(1) */
981 o(0xc1 + (a << 3));
982 } else {
983 /* if saved lvalue, then we must reload it */
984 r = vtop->r;
985 if ((r & VT_VALMASK) == VT_LLOCAL) {
986 SValue v1;
987 r = get_reg(RC_INT);
988 v1.type.t = VT_INT;
989 v1.r = VT_LOCAL | VT_LVAL;
990 v1.c.i = fc;
991 load(r, &v1);
992 fc = 0;
995 if ((ft & VT_BTYPE) == VT_DOUBLE)
996 o(0xdc);
997 else
998 o(0xd8);
999 gen_modrm(a, r, vtop->sym, fc);
1001 vtop--;
1005 /* convert integers to fp 't' type. Must handle 'int', 'unsigned int'
1006 and 'long long' cases. */
1007 ST_FUNC void gen_cvt_itof(int t)
1009 save_reg(TREG_ST0);
1010 gv(RC_INT);
1011 if ((vtop->type.t & VT_BTYPE) == VT_LLONG) {
1012 /* signed long long to float/double/long double (unsigned case
1013 is handled generically) */
1014 o(0x50 + vtop->r2); /* push r2 */
1015 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
1016 o(0x242cdf); /* fildll (%esp) */
1017 o(0x08c483); /* add $8, %esp */
1018 } else if ((vtop->type.t & (VT_BTYPE | VT_UNSIGNED)) ==
1019 (VT_INT | VT_UNSIGNED)) {
1020 /* unsigned int to float/double/long double */
1021 o(0x6a); /* push $0 */
1022 g(0x00);
1023 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
1024 o(0x242cdf); /* fildll (%esp) */
1025 o(0x08c483); /* add $8, %esp */
1026 } else {
1027 /* int to float/double/long double */
1028 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
1029 o(0x2404db); /* fildl (%esp) */
1030 o(0x04c483); /* add $4, %esp */
1032 vtop->r = TREG_ST0;
1035 /* convert fp to int 't' type */
1036 ST_FUNC void gen_cvt_ftoi(int t)
1038 int bt = vtop->type.t & VT_BTYPE;
1039 if (bt == VT_FLOAT)
1040 vpush_global_sym(&func_old_type, TOK___fixsfdi);
1041 else if (bt == VT_LDOUBLE)
1042 vpush_global_sym(&func_old_type, TOK___fixxfdi);
1043 else
1044 vpush_global_sym(&func_old_type, TOK___fixdfdi);
1045 vswap();
1046 gfunc_call(1);
1047 vpushi(0);
1048 vtop->r = REG_IRET;
1049 vtop->r2 = REG_LRET;
1052 /* convert from one floating point type to another */
1053 ST_FUNC void gen_cvt_ftof(int t)
1055 /* all we have to do on i386 is to put the float in a register */
1056 gv(RC_FLOAT);
1059 /* computed goto support */
1060 ST_FUNC void ggoto(void)
1062 gcall_or_jmp(1);
1063 vtop--;
1066 /* bound check support functions */
1067 #ifdef CONFIG_TCC_BCHECK
1069 /* generate a bounded pointer addition */
1070 ST_FUNC void gen_bounded_ptr_add(void)
1072 /* prepare fast i386 function call (args in eax and edx) */
1073 gv2(RC_EAX, RC_EDX);
1074 /* save all temporary registers */
1075 vtop -= 2;
1076 save_regs(0);
1077 /* do a fast function call */
1078 gen_static_call(TOK___bound_ptr_add);
1079 /* returned pointer is in eax */
1080 vtop++;
1081 vtop->r = TREG_EAX | VT_BOUNDED;
1082 /* address of bounding function call point */
1083 vtop->c.i = (cur_text_section->reloc->data_offset - sizeof(Elf32_Rel));
1086 /* patch pointer addition in vtop so that pointer dereferencing is
1087 also tested */
1088 ST_FUNC void gen_bounded_ptr_deref(void)
1090 addr_t func;
1091 int size, align;
1092 Elf32_Rel *rel;
1093 Sym *sym;
1095 size = 0;
1096 /* XXX: put that code in generic part of tcc */
1097 if (!is_float(vtop->type.t)) {
1098 if (vtop->r & VT_LVAL_BYTE)
1099 size = 1;
1100 else if (vtop->r & VT_LVAL_SHORT)
1101 size = 2;
1103 if (!size)
1104 size = type_size(&vtop->type, &align);
1105 switch(size) {
1106 case 1: func = TOK___bound_ptr_indir1; break;
1107 case 2: func = TOK___bound_ptr_indir2; break;
1108 case 4: func = TOK___bound_ptr_indir4; break;
1109 case 8: func = TOK___bound_ptr_indir8; break;
1110 case 12: func = TOK___bound_ptr_indir12; break;
1111 case 16: func = TOK___bound_ptr_indir16; break;
1112 default:
1113 tcc_error("unhandled size when dereferencing bounded pointer");
1114 func = 0;
1115 break;
1118 /* patch relocation */
1119 /* XXX: find a better solution ? */
1120 rel = (Elf32_Rel *)(cur_text_section->reloc->data + vtop->c.i);
1121 sym = external_global_sym(func, &func_old_type, 0);
1122 if (!sym->c)
1123 put_extern_sym(sym, NULL, 0, 0);
1124 rel->r_info = ELF32_R_INFO(sym->c, ELF32_R_TYPE(rel->r_info));
1126 #endif
1128 /* Save the stack pointer onto the stack */
1129 ST_FUNC void gen_vla_sp_save(int addr) {
1130 /* mov %esp,addr(%ebp)*/
1131 o(0x89);
1132 gen_modrm(TREG_ESP, VT_LOCAL, NULL, addr);
1135 /* Restore the SP from a location on the stack */
1136 ST_FUNC void gen_vla_sp_restore(int addr) {
1137 o(0x8b);
1138 gen_modrm(TREG_ESP, VT_LOCAL, NULL, addr);
1141 /* Subtract from the stack pointer, and push the resulting value onto the stack */
1142 ST_FUNC void gen_vla_alloc(CType *type, int align) {
1143 #ifdef TCC_TARGET_PE
1144 /* alloca does more than just adjust %rsp on Windows */
1145 vpush_global_sym(&func_old_type, TOK_alloca);
1146 vswap(); /* Move alloca ref past allocation size */
1147 gfunc_call(1);
1148 #else
1149 int r;
1150 r = gv(RC_INT); /* allocation size */
1151 /* sub r,%rsp */
1152 o(0x2b);
1153 o(0xe0 | r);
1154 /* We align to 16 bytes rather than align */
1155 /* and ~15, %esp */
1156 o(0xf0e483);
1157 vpop();
1158 #endif
1161 /* end of X86 code generator */
1162 /*************************************************************/
1163 #endif
1164 /*************************************************************/