Removed the error message and minor changes.
[tinycc.git] / i386-gen.c
1 /*
2 * X86 code generator for TCC
3 *
4 * Copyright (c) 2001-2004 Fabrice Bellard
5 *
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.
10 *
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.
15 *
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
19 */
20
21 #ifdef TARGET_DEFS_ONLY
22
23 /* number of available registers */
24 #define NB_REGS 4
25 #define NB_ASM_REGS 8
26
27 /* a register can belong to several classes. The classes must be
28 sorted from more general to more precise (see gv2() code which does
29 assumptions on it). */
30 #define RC_INT 0x0001 /* generic integer register */
31 #define RC_FLOAT 0x0002 /* generic float register */
32 #define RC_EAX 0x0004
33 #define RC_ST0 0x0008
34 #define RC_ECX 0x0010
35 #define RC_EDX 0x0020
36 #define RC_IRET RC_EAX /* function return: integer register */
37 #define RC_LRET RC_EDX /* function return: second integer register */
38 #define RC_FRET RC_ST0 /* function return: float register */
39
40 /* pretty names for the registers */
41 enum {
42 TREG_EAX = 0,
43 TREG_ECX,
44 TREG_EDX,
45 TREG_ST0,
46 TREG_ESP = 4
47 };
48
49 /* return registers for function */
50 #define REG_IRET TREG_EAX /* single word int return register */
51 #define REG_LRET TREG_EDX /* second word return register (for long long) */
52 #define REG_FRET TREG_ST0 /* float return register */
53
54 /* defined if function parameters must be evaluated in reverse order */
55 #define INVERT_FUNC_PARAMS
56
57 /* defined if structures are passed as pointers. Otherwise structures
58 are directly pushed on stack. */
59 /* #define FUNC_STRUCT_PARAM_AS_PTR */
60
61 /* pointer size, in bytes */
62 #define PTR_SIZE 4
63
64 /* long double size and alignment, in bytes */
65 #define LDOUBLE_SIZE 12
66 #define LDOUBLE_ALIGN 4
67 /* maximum alignment (for aligned attribute support) */
68 #define MAX_ALIGN 8
69
70
71 #define psym oad
72
73 /******************************************************/
74 /* ELF defines */
75
76 #define EM_TCC_TARGET EM_386
77
78 /* relocation type for 32 bit data relocation */
79 #define R_DATA_32 R_386_32
80 #define R_DATA_PTR R_386_32
81 #define R_JMP_SLOT R_386_JMP_SLOT
82 #define R_COPY R_386_COPY
83
84 #define ELF_START_ADDR 0x08048000
85 #define ELF_PAGE_SIZE 0x1000
86
87 /******************************************************/
88 #else /* ! TARGET_DEFS_ONLY */
89 /******************************************************/
90 #include "tcc.h"
91
92 ST_DATA const int reg_classes[NB_REGS] = {
93 /* eax */ RC_INT | RC_EAX,
94 /* ecx */ RC_INT | RC_ECX,
95 /* edx */ RC_INT | RC_EDX,
96 /* st0 */ RC_FLOAT | RC_ST0,
97 };
98
99 static unsigned long func_sub_sp_offset;
100 static int func_ret_sub;
101 #ifdef CONFIG_TCC_BCHECK
102 static unsigned long func_bound_offset;
103 #endif
104
105 /* XXX: make it faster ? */
106 ST_FUNC void g(int c)
107 {
108 int ind1;
109 ind1 = ind + 1;
110 if (ind1 > cur_text_section->data_allocated)
111 section_realloc(cur_text_section, ind1);
112 cur_text_section->data[ind] = c;
113 ind = ind1;
114 }
115
116 ST_FUNC void o(unsigned int c)
117 {
118 while (c) {
119 g(c);
120 c = c >> 8;
121 }
122 }
123
124 ST_FUNC void gen_le16(int v)
125 {
126 g(v);
127 g(v >> 8);
128 }
129
130 ST_FUNC void gen_le32(int c)
131 {
132 g(c);
133 g(c >> 8);
134 g(c >> 16);
135 g(c >> 24);
136 }
137
138 /* output a symbol and patch all calls to it */
139 ST_FUNC void gsym_addr(int t, int a)
140 {
141 int n, *ptr;
142 while (t) {
143 ptr = (int *)(cur_text_section->data + t);
144 n = *ptr; /* next value */
145 *ptr = a - t - 4;
146 t = n;
147 }
148 }
149
150 ST_FUNC void gsym(int t)
151 {
152 gsym_addr(t, ind);
153 }
154
155 /* psym is used to put an instruction with a data field which is a
156 reference to a symbol. It is in fact the same as oad ! */
157 #define psym oad
158
159 /* instruction + 4 bytes data. Return the address of the data */
160 ST_FUNC int oad(int c, int s)
161 {
162 int ind1;
163
164 o(c);
165 ind1 = ind + 4;
166 if (ind1 > cur_text_section->data_allocated)
167 section_realloc(cur_text_section, ind1);
168 *(int *)(cur_text_section->data + ind) = s;
169 s = ind;
170 ind = ind1;
171 return s;
172 }
173
174 /* output constant with relocation if 'r & VT_SYM' is true */
175 ST_FUNC void gen_addr32(int r, Sym *sym, int c)
176 {
177 if (r & VT_SYM)
178 greloc(cur_text_section, sym, ind, R_386_32);
179 gen_le32(c);
180 }
181
182 ST_FUNC void gen_addrpc32(int r, Sym *sym, int c)
183 {
184 if (r & VT_SYM)
185 greloc(cur_text_section, sym, ind, R_386_PC32);
186 gen_le32(c - 4);
187 }
188
189 /* generate a modrm reference. 'op_reg' contains the addtionnal 3
190 opcode bits */
191 static void gen_modrm(int op_reg, int r, Sym *sym, int c)
192 {
193 op_reg = op_reg << 3;
194 if ((r & VT_VALMASK) == VT_CONST) {
195 /* constant memory reference */
196 o(0x05 | op_reg);
197 gen_addr32(r, sym, c);
198 } else if ((r & VT_VALMASK) == VT_LOCAL) {
199 /* currently, we use only ebp as base */
200 if (c == (char)c) {
201 /* short reference */
202 o(0x45 | op_reg);
203 g(c);
204 } else {
205 oad(0x85 | op_reg, c);
206 }
207 } else {
208 g(0x00 | op_reg | (r & VT_VALMASK));
209 }
210 }
211
212 /* load 'r' from value 'sv' */
213 ST_FUNC void load(int r, SValue *sv)
214 {
215 int v, t, ft, fc, fr;
216 SValue v1;
217
218 #ifdef TCC_TARGET_PE
219 SValue v2;
220 sv = pe_getimport(sv, &v2);
221 #endif
222
223 fr = sv->r;
224 ft = sv->type.t;
225 fc = sv->c.ul;
226
227 v = fr & VT_VALMASK;
228 if (fr & VT_LVAL) {
229 if (v == VT_LLOCAL) {
230 v1.type.t = VT_INT;
231 v1.r = VT_LOCAL | VT_LVAL;
232 v1.c.ul = fc;
233 fr = r;
234 if (!(reg_classes[fr] & RC_INT))
235 fr = get_reg(RC_INT);
236 load(fr, &v1);
237 }
238 if ((ft & VT_BTYPE) == VT_FLOAT) {
239 o(0xd9); /* flds */
240 r = 0;
241 } else if ((ft & VT_BTYPE) == VT_DOUBLE) {
242 o(0xdd); /* fldl */
243 r = 0;
244 } else if ((ft & VT_BTYPE) == VT_LDOUBLE) {
245 o(0xdb); /* fldt */
246 r = 5;
247 } else if ((ft & VT_TYPE) == VT_BYTE || (ft & VT_TYPE) == VT_BOOL) {
248 o(0xbe0f); /* movsbl */
249 } else if ((ft & VT_TYPE) == (VT_BYTE | VT_UNSIGNED)) {
250 o(0xb60f); /* movzbl */
251 } else if ((ft & VT_TYPE) == VT_SHORT) {
252 o(0xbf0f); /* movswl */
253 } else if ((ft & VT_TYPE) == (VT_SHORT | VT_UNSIGNED)) {
254 o(0xb70f); /* movzwl */
255 } else {
256 o(0x8b); /* movl */
257 }
258 gen_modrm(r, fr, sv->sym, fc);
259 } else {
260 if (v == VT_CONST) {
261 o(0xb8 + r); /* mov $xx, r */
262 gen_addr32(fr, sv->sym, fc);
263 } else if (v == VT_LOCAL) {
264 if (fc) {
265 o(0x8d); /* lea xxx(%ebp), r */
266 gen_modrm(r, VT_LOCAL, sv->sym, fc);
267 } else {
268 o(0x89);
269 o(0xe8 + r); /* mov %ebp, r */
270 }
271 } else if (v == VT_CMP) {
272 oad(0xb8 + r, 0); /* mov $0, r */
273 o(0x0f); /* setxx %br */
274 o(fc);
275 o(0xc0 + r);
276 } else if (v == VT_JMP || v == VT_JMPI) {
277 t = v & 1;
278 oad(0xb8 + r, t); /* mov $1, r */
279 o(0x05eb); /* jmp after */
280 gsym(fc);
281 oad(0xb8 + r, t ^ 1); /* mov $0, r */
282 } else if (v != r) {
283 o(0x89);
284 o(0xc0 + r + v * 8); /* mov v, r */
285 }
286 }
287 }
288
289 /* store register 'r' in lvalue 'v' */
290 ST_FUNC void store(int r, SValue *v)
291 {
292 int fr, bt, ft, fc;
293
294 #ifdef TCC_TARGET_PE
295 SValue v2;
296 v = pe_getimport(v, &v2);
297 #endif
298
299 ft = v->type.t;
300 fc = v->c.ul;
301 fr = v->r & VT_VALMASK;
302 bt = ft & VT_BTYPE;
303 /* XXX: incorrect if float reg to reg */
304 if (bt == VT_FLOAT) {
305 o(0xd9); /* fsts */
306 r = 2;
307 } else if (bt == VT_DOUBLE) {
308 o(0xdd); /* fstpl */
309 r = 2;
310 } else if (bt == VT_LDOUBLE) {
311 o(0xc0d9); /* fld %st(0) */
312 o(0xdb); /* fstpt */
313 r = 7;
314 } else {
315 if (bt == VT_SHORT)
316 o(0x66);
317 if (bt == VT_BYTE || bt == VT_BOOL)
318 o(0x88);
319 else
320 o(0x89);
321 }
322 if (fr == VT_CONST ||
323 fr == VT_LOCAL ||
324 (v->r & VT_LVAL)) {
325 gen_modrm(r, v->r, v->sym, fc);
326 } else if (fr != r) {
327 o(0xc0 + fr + r * 8); /* mov r, fr */
328 }
329 }
330
331 static void gadd_sp(int val)
332 {
333 if (val == (char)val) {
334 o(0xc483);
335 g(val);
336 } else {
337 oad(0xc481, val); /* add $xxx, %esp */
338 }
339 }
340
341 static void gen_static_call(int v)
342 {
343 Sym *sym;
344
345 sym = external_global_sym(v, &func_old_type, 0);
346 oad(0xe8, -4);
347 greloc(cur_text_section, sym, ind-4, R_386_PC32);
348 }
349
350 /* 'is_jmp' is '1' if it is a jump */
351 static void gcall_or_jmp(int is_jmp)
352 {
353 int r;
354 if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
355 /* constant case */
356 if (vtop->r & VT_SYM) {
357 /* relocation case */
358 greloc(cur_text_section, vtop->sym,
359 ind + 1, R_386_PC32);
360 } else {
361 /* put an empty PC32 relocation */
362 put_elf_reloc(symtab_section, cur_text_section,
363 ind + 1, R_386_PC32, 0);
364 }
365 oad(0xe8 + is_jmp, vtop->c.ul - 4); /* call/jmp im */
366 } else {
367 /* otherwise, indirect call */
368 r = gv(RC_INT);
369 o(0xff); /* call/jmp *r */
370 o(0xd0 + r + (is_jmp << 4));
371 }
372 }
373
374 static uint8_t fastcall_regs[3] = { TREG_EAX, TREG_EDX, TREG_ECX };
375 static uint8_t fastcallw_regs[2] = { TREG_ECX, TREG_EDX };
376
377 /* Return the number of registers needed to return the struct, or 0 if
378 returning via struct pointer. */
379 ST_FUNC int gfunc_sret(CType *vt, int variadic, CType *ret, int *ret_align)
380 {
381 #ifdef TCC_TARGET_PE
382 int size, align;
383
384 *ret_align = 1; // Never have to re-align return values for x86
385 size = type_size(vt, &align);
386 if (size > 8) {
387 return 0;
388 } else if (size > 4) {
389 ret->ref = NULL;
390 ret->t = VT_LLONG;
391 return 1;
392 } else {
393 ret->ref = NULL;
394 ret->t = VT_INT;
395 return 1;
396 }
397 #else
398 *ret_align = 1; // Never have to re-align return values for x86
399 return 0;
400 #endif
401 }
402
403 /* Generate function call. The function address is pushed first, then
404 all the parameters in call order. This functions pops all the
405 parameters and the function address. */
406 ST_FUNC void gfunc_call(int nb_args)
407 {
408 int size, align, r, args_size, i, func_call;
409 Sym *func_sym;
410
411 args_size = 0;
412 for(i = 0;i < nb_args; i++) {
413 if ((vtop->type.t & VT_BTYPE) == VT_STRUCT) {
414 size = type_size(&vtop->type, &align);
415 /* align to stack align size */
416 size = (size + 3) & ~3;
417 /* allocate the necessary size on stack */
418 oad(0xec81, size); /* sub $xxx, %esp */
419 /* generate structure store */
420 r = get_reg(RC_INT);
421 o(0x89); /* mov %esp, r */
422 o(0xe0 + r);
423 vset(&vtop->type, r | VT_LVAL, 0);
424 vswap();
425 vstore();
426 args_size += size;
427 } else if (is_float(vtop->type.t)) {
428 gv(RC_FLOAT); /* only one float register */
429 if ((vtop->type.t & VT_BTYPE) == VT_FLOAT)
430 size = 4;
431 else if ((vtop->type.t & VT_BTYPE) == VT_DOUBLE)
432 size = 8;
433 else
434 size = 12;
435 oad(0xec81, size); /* sub $xxx, %esp */
436 if (size == 12)
437 o(0x7cdb);
438 else
439 o(0x5cd9 + size - 4); /* fstp[s|l] 0(%esp) */
440 g(0x24);
441 g(0x00);
442 args_size += size;
443 } else {
444 /* simple type (currently always same size) */
445 /* XXX: implicit cast ? */
446 r = gv(RC_INT);
447 if ((vtop->type.t & VT_BTYPE) == VT_LLONG) {
448 size = 8;
449 o(0x50 + vtop->r2); /* push r */
450 } else {
451 size = 4;
452 }
453 o(0x50 + r); /* push r */
454 args_size += size;
455 }
456 vtop--;
457 }
458 save_regs(0); /* save used temporary registers */
459 func_sym = vtop->type.ref;
460 func_call = func_sym->a.func_call;
461 /* fast call case */
462 if ((func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) ||
463 func_call == FUNC_FASTCALLW) {
464 int fastcall_nb_regs;
465 uint8_t *fastcall_regs_ptr;
466 if (func_call == FUNC_FASTCALLW) {
467 fastcall_regs_ptr = fastcallw_regs;
468 fastcall_nb_regs = 2;
469 } else {
470 fastcall_regs_ptr = fastcall_regs;
471 fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
472 }
473 for(i = 0;i < fastcall_nb_regs; i++) {
474 if (args_size <= 0)
475 break;
476 o(0x58 + fastcall_regs_ptr[i]); /* pop r */
477 /* XXX: incorrect for struct/floats */
478 args_size -= 4;
479 }
480 }
481 #ifndef TCC_TARGET_PE
482 else if ((vtop->type.ref->type.t & VT_BTYPE) == VT_STRUCT)
483 args_size -= 4;
484 #endif
485 gcall_or_jmp(0);
486
487 if (args_size && func_call != FUNC_STDCALL)
488 gadd_sp(args_size);
489 vtop--;
490 }
491
492 #ifdef TCC_TARGET_PE
493 #define FUNC_PROLOG_SIZE 10
494 #else
495 #define FUNC_PROLOG_SIZE 9
496 #endif
497
498 /* generate function prolog of type 't' */
499 ST_FUNC void gfunc_prolog(CType *func_type)
500 {
501 int addr, align, size, func_call, fastcall_nb_regs;
502 int param_index, param_addr;
503 uint8_t *fastcall_regs_ptr;
504 Sym *sym;
505 CType *type;
506
507 sym = func_type->ref;
508 func_call = sym->a.func_call;
509 addr = 8;
510 loc = 0;
511 func_vc = 0;
512
513 if (func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) {
514 fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
515 fastcall_regs_ptr = fastcall_regs;
516 } else if (func_call == FUNC_FASTCALLW) {
517 fastcall_nb_regs = 2;
518 fastcall_regs_ptr = fastcallw_regs;
519 } else {
520 fastcall_nb_regs = 0;
521 fastcall_regs_ptr = NULL;
522 }
523 param_index = 0;
524
525 ind += FUNC_PROLOG_SIZE;
526 func_sub_sp_offset = ind;
527 /* if the function returns a structure, then add an
528 implicit pointer parameter */
529 func_vt = sym->type;
530 func_var = (sym->c == FUNC_ELLIPSIS);
531 #ifdef TCC_TARGET_PE
532 size = type_size(&func_vt,&align);
533 if (((func_vt.t & VT_BTYPE) == VT_STRUCT) && (size > 8)) {
534 #else
535 if ((func_vt.t & VT_BTYPE) == VT_STRUCT) {
536 #endif
537 /* XXX: fastcall case ? */
538 func_vc = addr;
539 addr += 4;
540 param_index++;
541 }
542 /* define parameters */
543 while ((sym = sym->next) != NULL) {
544 type = &sym->type;
545 size = type_size(type, &align);
546 size = (size + 3) & ~3;
547 #ifdef FUNC_STRUCT_PARAM_AS_PTR
548 /* structs are passed as pointer */
549 if ((type->t & VT_BTYPE) == VT_STRUCT) {
550 size = 4;
551 }
552 #endif
553 if (param_index < fastcall_nb_regs) {
554 /* save FASTCALL register */
555 loc -= 4;
556 o(0x89); /* movl */
557 gen_modrm(fastcall_regs_ptr[param_index], VT_LOCAL, NULL, loc);
558 param_addr = loc;
559 } else {
560 param_addr = addr;
561 addr += size;
562 }
563 sym_push(sym->v & ~SYM_FIELD, type,
564 VT_LOCAL | lvalue_type(type->t), param_addr);
565 param_index++;
566 }
567 func_ret_sub = 0;
568 /* pascal type call ? */
569 if (func_call == FUNC_STDCALL)
570 func_ret_sub = addr - 8;
571 #ifndef TCC_TARGET_PE
572 else if (func_vc)
573 func_ret_sub = 4;
574 #endif
575
576 #ifdef CONFIG_TCC_BCHECK
577 /* leave some room for bound checking code */
578 if (tcc_state->do_bounds_check) {
579 oad(0xb8, 0); /* lbound section pointer */
580 oad(0xb8, 0); /* call to function */
581 func_bound_offset = lbounds_section->data_offset;
582 }
583 #endif
584 }
585
586 /* generate function epilog */
587 ST_FUNC void gfunc_epilog(void)
588 {
589 int v, saved_ind;
590
591 #ifdef CONFIG_TCC_BCHECK
592 if (tcc_state->do_bounds_check
593 && func_bound_offset != lbounds_section->data_offset) {
594 int saved_ind;
595 int *bounds_ptr;
596 Sym *sym_data;
597 /* add end of table info */
598 bounds_ptr = section_ptr_add(lbounds_section, sizeof(int));
599 *bounds_ptr = 0;
600 /* generate bound local allocation */
601 saved_ind = ind;
602 ind = func_sub_sp_offset;
603 sym_data = get_sym_ref(&char_pointer_type, lbounds_section,
604 func_bound_offset, lbounds_section->data_offset);
605 greloc(cur_text_section, sym_data,
606 ind + 1, R_386_32);
607 oad(0xb8, 0); /* mov %eax, xxx */
608 gen_static_call(TOK___bound_local_new);
609
610 ind = saved_ind;
611 /* generate bound check local freeing */
612 o(0x5250); /* save returned value, if any */
613 greloc(cur_text_section, sym_data,
614 ind + 1, R_386_32);
615 oad(0xb8, 0); /* mov %eax, xxx */
616 gen_static_call(TOK___bound_local_delete);
617
618 o(0x585a); /* restore returned value, if any */
619 }
620 #endif
621 o(0xc9); /* leave */
622 if (func_ret_sub == 0) {
623 o(0xc3); /* ret */
624 } else {
625 o(0xc2); /* ret n */
626 g(func_ret_sub);
627 g(func_ret_sub >> 8);
628 }
629 /* align local size to word & save local variables */
630
631 v = (-loc + 3) & -4;
632 saved_ind = ind;
633 ind = func_sub_sp_offset - FUNC_PROLOG_SIZE;
634 #ifdef TCC_TARGET_PE
635 if (v >= 4096) {
636 oad(0xb8, v); /* mov stacksize, %eax */
637 gen_static_call(TOK___chkstk); /* call __chkstk, (does the stackframe too) */
638 } else
639 #endif
640 {
641 o(0xe58955); /* push %ebp, mov %esp, %ebp */
642 o(0xec81); /* sub esp, stacksize */
643 gen_le32(v);
644 #if FUNC_PROLOG_SIZE == 10
645 o(0x90); /* adjust to FUNC_PROLOG_SIZE */
646 #endif
647 }
648 ind = saved_ind;
649 }
650
651 /* generate a jump to a label */
652 ST_FUNC int gjmp(int t)
653 {
654 return psym(0xe9, t);
655 }
656
657 /* generate a jump to a fixed address */
658 ST_FUNC void gjmp_addr(int a)
659 {
660 int r;
661 r = a - ind - 2;
662 if (r == (char)r) {
663 g(0xeb);
664 g(r);
665 } else {
666 oad(0xe9, a - ind - 5);
667 }
668 }
669
670 /* generate a test. set 'inv' to invert test. Stack entry is popped */
671 ST_FUNC int gtst(int inv, int t)
672 {
673 int v, *p;
674
675 v = vtop->r & VT_VALMASK;
676 if (v == VT_CMP) {
677 /* fast case : can jump directly since flags are set */
678 g(0x0f);
679 t = psym((vtop->c.i - 16) ^ inv, t);
680 } else { /* VT_JMP || VT_JMPI */
681 /* && or || optimization */
682 if ((v & 1) == inv) {
683 /* insert vtop->c jump list in t */
684 p = &vtop->c.i;
685 while (*p != 0)
686 p = (int *)(cur_text_section->data + *p);
687 *p = t;
688 t = vtop->c.i;
689 } else {
690 t = gjmp(t);
691 gsym(vtop->c.i);
692 }
693 }
694 vtop--;
695 return t;
696 }
697
698 /* generate an integer binary operation */
699 ST_FUNC void gen_opi(int op)
700 {
701 int r, fr, opc, c;
702
703 switch(op) {
704 case '+':
705 case TOK_ADDC1: /* add with carry generation */
706 opc = 0;
707 gen_op8:
708 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
709 /* constant case */
710 vswap();
711 r = gv(RC_INT);
712 vswap();
713 c = vtop->c.i;
714 if (c == (char)c) {
715 /* generate inc and dec for smaller code */
716 if (c==1 && opc==0) {
717 o (0x40 | r); // inc
718 } else if (c==1 && opc==5) {
719 o (0x48 | r); // dec
720 } else {
721 o(0x83);
722 o(0xc0 | (opc << 3) | r);
723 g(c);
724 }
725 } else {
726 o(0x81);
727 oad(0xc0 | (opc << 3) | r, c);
728 }
729 } else {
730 gv2(RC_INT, RC_INT);
731 r = vtop[-1].r;
732 fr = vtop[0].r;
733 o((opc << 3) | 0x01);
734 o(0xc0 + r + fr * 8);
735 }
736 vtop--;
737 if (op >= TOK_ULT && op <= TOK_GT) {
738 vtop->r = VT_CMP;
739 vtop->c.i = op;
740 }
741 break;
742 case '-':
743 case TOK_SUBC1: /* sub with carry generation */
744 opc = 5;
745 goto gen_op8;
746 case TOK_ADDC2: /* add with carry use */
747 opc = 2;
748 goto gen_op8;
749 case TOK_SUBC2: /* sub with carry use */
750 opc = 3;
751 goto gen_op8;
752 case '&':
753 opc = 4;
754 goto gen_op8;
755 case '^':
756 opc = 6;
757 goto gen_op8;
758 case '|':
759 opc = 1;
760 goto gen_op8;
761 case '*':
762 gv2(RC_INT, RC_INT);
763 r = vtop[-1].r;
764 fr = vtop[0].r;
765 vtop--;
766 o(0xaf0f); /* imul fr, r */
767 o(0xc0 + fr + r * 8);
768 break;
769 case TOK_SHL:
770 opc = 4;
771 goto gen_shift;
772 case TOK_SHR:
773 opc = 5;
774 goto gen_shift;
775 case TOK_SAR:
776 opc = 7;
777 gen_shift:
778 opc = 0xc0 | (opc << 3);
779 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
780 /* constant case */
781 vswap();
782 r = gv(RC_INT);
783 vswap();
784 c = vtop->c.i & 0x1f;
785 o(0xc1); /* shl/shr/sar $xxx, r */
786 o(opc | r);
787 g(c);
788 } else {
789 /* we generate the shift in ecx */
790 gv2(RC_INT, RC_ECX);
791 r = vtop[-1].r;
792 o(0xd3); /* shl/shr/sar %cl, r */
793 o(opc | r);
794 }
795 vtop--;
796 break;
797 case '/':
798 case TOK_UDIV:
799 case TOK_PDIV:
800 case '%':
801 case TOK_UMOD:
802 case TOK_UMULL:
803 /* first operand must be in eax */
804 /* XXX: need better constraint for second operand */
805 gv2(RC_EAX, RC_ECX);
806 r = vtop[-1].r;
807 fr = vtop[0].r;
808 vtop--;
809 save_reg(TREG_EDX);
810 if (op == TOK_UMULL) {
811 o(0xf7); /* mul fr */
812 o(0xe0 + fr);
813 vtop->r2 = TREG_EDX;
814 r = TREG_EAX;
815 } else {
816 if (op == TOK_UDIV || op == TOK_UMOD) {
817 o(0xf7d231); /* xor %edx, %edx, div fr, %eax */
818 o(0xf0 + fr);
819 } else {
820 o(0xf799); /* cltd, idiv fr, %eax */
821 o(0xf8 + fr);
822 }
823 if (op == '%' || op == TOK_UMOD)
824 r = TREG_EDX;
825 else
826 r = TREG_EAX;
827 }
828 vtop->r = r;
829 break;
830 default:
831 opc = 7;
832 goto gen_op8;
833 }
834 }
835
836 /* generate a floating point operation 'v = t1 op t2' instruction. The
837 two operands are guaranted to have the same floating point type */
838 /* XXX: need to use ST1 too */
839 ST_FUNC void gen_opf(int op)
840 {
841 int a, ft, fc, swapped, r;
842
843 /* convert constants to memory references */
844 if ((vtop[-1].r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
845 vswap();
846 gv(RC_FLOAT);
847 vswap();
848 }
849 if ((vtop[0].r & (VT_VALMASK | VT_LVAL)) == VT_CONST)
850 gv(RC_FLOAT);
851
852 /* must put at least one value in the floating point register */
853 if ((vtop[-1].r & VT_LVAL) &&
854 (vtop[0].r & VT_LVAL)) {
855 vswap();
856 gv(RC_FLOAT);
857 vswap();
858 }
859 swapped = 0;
860 /* swap the stack if needed so that t1 is the register and t2 is
861 the memory reference */
862 if (vtop[-1].r & VT_LVAL) {
863 vswap();
864 swapped = 1;
865 }
866 if (op >= TOK_ULT && op <= TOK_GT) {
867 /* load on stack second operand */
868 load(TREG_ST0, vtop);
869 save_reg(TREG_EAX); /* eax is used by FP comparison code */
870 if (op == TOK_GE || op == TOK_GT)
871 swapped = !swapped;
872 else if (op == TOK_EQ || op == TOK_NE)
873 swapped = 0;
874 if (swapped)
875 o(0xc9d9); /* fxch %st(1) */
876 if (op == TOK_EQ || op == TOK_NE)
877 o(0xe9da); /* fucompp */
878 else
879 o(0xd9de); /* fcompp */
880 o(0xe0df); /* fnstsw %ax */
881 if (op == TOK_EQ) {
882 o(0x45e480); /* and $0x45, %ah */
883 o(0x40fC80); /* cmp $0x40, %ah */
884 } else if (op == TOK_NE) {
885 o(0x45e480); /* and $0x45, %ah */
886 o(0x40f480); /* xor $0x40, %ah */
887 op = TOK_NE;
888 } else if (op == TOK_GE || op == TOK_LE) {
889 o(0x05c4f6); /* test $0x05, %ah */
890 op = TOK_EQ;
891 } else {
892 o(0x45c4f6); /* test $0x45, %ah */
893 op = TOK_EQ;
894 }
895 vtop--;
896 vtop->r = VT_CMP;
897 vtop->c.i = op;
898 } else {
899 /* no memory reference possible for long double operations */
900 if ((vtop->type.t & VT_BTYPE) == VT_LDOUBLE) {
901 load(TREG_ST0, vtop);
902 swapped = !swapped;
903 }
904
905 switch(op) {
906 default:
907 case '+':
908 a = 0;
909 break;
910 case '-':
911 a = 4;
912 if (swapped)
913 a++;
914 break;
915 case '*':
916 a = 1;
917 break;
918 case '/':
919 a = 6;
920 if (swapped)
921 a++;
922 break;
923 }
924 ft = vtop->type.t;
925 fc = vtop->c.ul;
926 if ((ft & VT_BTYPE) == VT_LDOUBLE) {
927 o(0xde); /* fxxxp %st, %st(1) */
928 o(0xc1 + (a << 3));
929 } else {
930 /* if saved lvalue, then we must reload it */
931 r = vtop->r;
932 if ((r & VT_VALMASK) == VT_LLOCAL) {
933 SValue v1;
934 r = get_reg(RC_INT);
935 v1.type.t = VT_INT;
936 v1.r = VT_LOCAL | VT_LVAL;
937 v1.c.ul = fc;
938 load(r, &v1);
939 fc = 0;
940 }
941
942 if ((ft & VT_BTYPE) == VT_DOUBLE)
943 o(0xdc);
944 else
945 o(0xd8);
946 gen_modrm(a, r, vtop->sym, fc);
947 }
948 vtop--;
949 }
950 }
951
952 /* convert integers to fp 't' type. Must handle 'int', 'unsigned int'
953 and 'long long' cases. */
954 ST_FUNC void gen_cvt_itof(int t)
955 {
956 save_reg(TREG_ST0);
957 gv(RC_INT);
958 if ((vtop->type.t & VT_BTYPE) == VT_LLONG) {
959 /* signed long long to float/double/long double (unsigned case
960 is handled generically) */
961 o(0x50 + vtop->r2); /* push r2 */
962 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
963 o(0x242cdf); /* fildll (%esp) */
964 o(0x08c483); /* add $8, %esp */
965 } else if ((vtop->type.t & (VT_BTYPE | VT_UNSIGNED)) ==
966 (VT_INT | VT_UNSIGNED)) {
967 /* unsigned int to float/double/long double */
968 o(0x6a); /* push $0 */
969 g(0x00);
970 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
971 o(0x242cdf); /* fildll (%esp) */
972 o(0x08c483); /* add $8, %esp */
973 } else {
974 /* int to float/double/long double */
975 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
976 o(0x2404db); /* fildl (%esp) */
977 o(0x04c483); /* add $4, %esp */
978 }
979 vtop->r = TREG_ST0;
980 }
981
982 /* convert fp to int 't' type */
983 ST_FUNC void gen_cvt_ftoi(int t)
984 {
985 int bt = vtop->type.t & VT_BTYPE;
986 if (bt == VT_FLOAT)
987 vpush_global_sym(&func_old_type, TOK___fixsfdi);
988 else if (bt == VT_LDOUBLE)
989 vpush_global_sym(&func_old_type, TOK___fixxfdi);
990 else
991 vpush_global_sym(&func_old_type, TOK___fixdfdi);
992 vswap();
993 gfunc_call(1);
994 vpushi(0);
995 vtop->r = REG_IRET;
996 vtop->r2 = REG_LRET;
997 }
998
999 /* convert from one floating point type to another */
1000 ST_FUNC void gen_cvt_ftof(int t)
1001 {
1002 /* all we have to do on i386 is to put the float in a register */
1003 gv(RC_FLOAT);
1004 }
1005
1006 /* computed goto support */
1007 ST_FUNC void ggoto(void)
1008 {
1009 gcall_or_jmp(1);
1010 vtop--;
1011 }
1012
1013 /* bound check support functions */
1014 #ifdef CONFIG_TCC_BCHECK
1015
1016 /* generate a bounded pointer addition */
1017 ST_FUNC void gen_bounded_ptr_add(void)
1018 {
1019 /* prepare fast i386 function call (args in eax and edx) */
1020 gv2(RC_EAX, RC_EDX);
1021 /* save all temporary registers */
1022 vtop -= 2;
1023 save_regs(0);
1024 /* do a fast function call */
1025 gen_static_call(TOK___bound_ptr_add);
1026 /* returned pointer is in eax */
1027 vtop++;
1028 vtop->r = TREG_EAX | VT_BOUNDED;
1029 /* address of bounding function call point */
1030 vtop->c.ul = (cur_text_section->reloc->data_offset - sizeof(Elf32_Rel));
1031 }
1032
1033 /* patch pointer addition in vtop so that pointer dereferencing is
1034 also tested */
1035 ST_FUNC void gen_bounded_ptr_deref(void)
1036 {
1037 int func;
1038 int size, align;
1039 Elf32_Rel *rel;
1040 Sym *sym;
1041
1042 size = 0;
1043 /* XXX: put that code in generic part of tcc */
1044 if (!is_float(vtop->type.t)) {
1045 if (vtop->r & VT_LVAL_BYTE)
1046 size = 1;
1047 else if (vtop->r & VT_LVAL_SHORT)
1048 size = 2;
1049 }
1050 if (!size)
1051 size = type_size(&vtop->type, &align);
1052 switch(size) {
1053 case 1: func = TOK___bound_ptr_indir1; break;
1054 case 2: func = TOK___bound_ptr_indir2; break;
1055 case 4: func = TOK___bound_ptr_indir4; break;
1056 case 8: func = TOK___bound_ptr_indir8; break;
1057 case 12: func = TOK___bound_ptr_indir12; break;
1058 case 16: func = TOK___bound_ptr_indir16; break;
1059 default:
1060 tcc_error("unhandled size when dereferencing bounded pointer");
1061 func = 0;
1062 break;
1063 }
1064
1065 /* patch relocation */
1066 /* XXX: find a better solution ? */
1067 rel = (Elf32_Rel *)(cur_text_section->reloc->data + vtop->c.ul);
1068 sym = external_global_sym(func, &func_old_type, 0);
1069 if (!sym->c)
1070 put_extern_sym(sym, NULL, 0, 0);
1071 rel->r_info = ELF32_R_INFO(sym->c, ELF32_R_TYPE(rel->r_info));
1072 }
1073 #endif
1074
1075 /* Save the stack pointer onto the stack */
1076 ST_FUNC void gen_vla_sp_save(int addr) {
1077 /* mov %esp,addr(%ebp)*/
1078 o(0x89);
1079 gen_modrm(TREG_ESP, VT_LOCAL, NULL, addr);
1080 }
1081
1082 /* Restore the SP from a location on the stack */
1083 ST_FUNC void gen_vla_sp_restore(int addr) {
1084 o(0x8b);
1085 gen_modrm(TREG_ESP, VT_LOCAL, NULL, addr);
1086 }
1087
1088 /* Subtract from the stack pointer, and push the resulting value onto the stack */
1089 ST_FUNC void gen_vla_alloc(CType *type, int align) {
1090 #ifdef TCC_TARGET_PE
1091 /* alloca does more than just adjust %rsp on Windows */
1092 vpush_global_sym(&func_old_type, TOK_alloca);
1093 vswap(); /* Move alloca ref past allocation size */
1094 gfunc_call(1);
1095 vset(type, REG_IRET, 0);
1096 #else
1097 int r;
1098 r = gv(RC_INT); /* allocation size */
1099 /* sub r,%rsp */
1100 o(0x2b);
1101 o(0xe0 | r);
1102 /* We align to 16 bytes rather than align */
1103 /* and ~15, %esp */
1104 o(0xf0e483);
1105 /* mov %esp, r */
1106 o(0x89);
1107 o(0xe0 | r);
1108 vpop();
1109 vset(type, r, 0);
1110 #endif
1111 }
1112
1113 /* end of X86 code generator */
1114 /*************************************************************/
1115 #endif
1116 /*************************************************************/