Revert "Add predictability in CType initialization."
[tinycc.git] / i386-gen.c
blobc3f03c7809770a9ca7fb6888c761e6e5dbfdef28
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 4
25 #define NB_ASM_REGS 8
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 */
40 /* pretty names for the registers */
41 enum {
42 TREG_EAX = 0,
43 TREG_ECX,
44 TREG_EDX,
45 TREG_ST0,
48 /* return registers for function */
49 #define REG_IRET TREG_EAX /* single word int return register */
50 #define REG_LRET TREG_EDX /* second word return register (for long long) */
51 #define REG_FRET TREG_ST0 /* float return register */
53 /* defined if function parameters must be evaluated in reverse order */
54 #define INVERT_FUNC_PARAMS
56 /* defined if structures are passed as pointers. Otherwise structures
57 are directly pushed on stack. */
58 //#define FUNC_STRUCT_PARAM_AS_PTR
60 /* pointer size, in bytes */
61 #define PTR_SIZE 4
63 /* long double size and alignment, in bytes */
64 #define LDOUBLE_SIZE 12
65 #define LDOUBLE_ALIGN 4
66 /* maximum alignment (for aligned attribute support) */
67 #define MAX_ALIGN 8
70 #define psym oad
72 /******************************************************/
73 /* ELF defines */
75 #define EM_TCC_TARGET EM_386
77 /* relocation type for 32 bit data relocation */
78 #define R_DATA_32 R_386_32
79 #define R_DATA_PTR R_386_32
80 #define R_JMP_SLOT R_386_JMP_SLOT
81 #define R_COPY R_386_COPY
83 #define ELF_START_ADDR 0x08048000
84 #define ELF_PAGE_SIZE 0x1000
86 /******************************************************/
87 #else /* ! TARGET_DEFS_ONLY */
88 /******************************************************/
89 #include "tcc.h"
91 ST_DATA const int reg_classes[NB_REGS] = {
92 /* eax */ RC_INT | RC_EAX,
93 /* ecx */ RC_INT | RC_ECX,
94 /* edx */ RC_INT | RC_EDX,
95 /* st0 */ RC_FLOAT | RC_ST0,
98 static unsigned long func_sub_sp_offset;
99 static int func_ret_sub;
100 #ifdef CONFIG_TCC_BCHECK
101 static unsigned long func_bound_offset;
102 #endif
104 /* XXX: make it faster ? */
105 ST_FUNC void g(int c)
107 int ind1;
108 ind1 = ind + 1;
109 if (ind1 > cur_text_section->data_allocated)
110 section_realloc(cur_text_section, ind1);
111 cur_text_section->data[ind] = c;
112 ind = ind1;
115 ST_FUNC void o(unsigned int c)
117 while (c) {
118 g(c);
119 c = c >> 8;
123 ST_FUNC void gen_le16(int v)
125 g(v);
126 g(v >> 8);
129 ST_FUNC void gen_le32(int c)
131 g(c);
132 g(c >> 8);
133 g(c >> 16);
134 g(c >> 24);
137 /* output a symbol and patch all calls to it */
138 ST_FUNC void gsym_addr(int t, int a)
140 int n, *ptr;
141 while (t) {
142 ptr = (int *)(cur_text_section->data + t);
143 n = *ptr; /* next value */
144 *ptr = a - t - 4;
145 t = n;
149 ST_FUNC void gsym(int t)
151 gsym_addr(t, ind);
154 /* psym is used to put an instruction with a data field which is a
155 reference to a symbol. It is in fact the same as oad ! */
156 #define psym oad
158 /* instruction + 4 bytes data. Return the address of the data */
159 ST_FUNC int oad(int c, int s)
161 int ind1;
163 o(c);
164 ind1 = ind + 4;
165 if (ind1 > cur_text_section->data_allocated)
166 section_realloc(cur_text_section, ind1);
167 *(int *)(cur_text_section->data + ind) = s;
168 s = ind;
169 ind = ind1;
170 return s;
173 /* output constant with relocation if 'r & VT_SYM' is true */
174 ST_FUNC void gen_addr32(int r, Sym *sym, int c)
176 if (r & VT_SYM)
177 greloc(cur_text_section, sym, ind, R_386_32);
178 gen_le32(c);
181 ST_FUNC void gen_addrpc32(int r, Sym *sym, int c)
183 if (r & VT_SYM)
184 greloc(cur_text_section, sym, ind, R_386_PC32);
185 gen_le32(c - 4);
188 /* generate a modrm reference. 'op_reg' contains the addtionnal 3
189 opcode bits */
190 static void gen_modrm(int op_reg, int r, Sym *sym, int c)
192 op_reg = op_reg << 3;
193 if ((r & VT_VALMASK) == VT_CONST) {
194 /* constant memory reference */
195 o(0x05 | op_reg);
196 gen_addr32(r, sym, c);
197 } else if ((r & VT_VALMASK) == VT_LOCAL) {
198 /* currently, we use only ebp as base */
199 if (c == (char)c) {
200 /* short reference */
201 o(0x45 | op_reg);
202 g(c);
203 } else {
204 oad(0x85 | op_reg, c);
206 } else {
207 g(0x00 | op_reg | (r & VT_VALMASK));
211 /* load 'r' from value 'sv' */
212 ST_FUNC void load(int r, SValue *sv)
214 int v, t, ft, fc, fr;
215 SValue v1;
217 #ifdef TCC_TARGET_PE
218 SValue v2;
219 sv = pe_getimport(sv, &v2);
220 #endif
222 fr = sv->r;
223 ft = sv->type.t;
224 fc = sv->c.ul;
226 v = fr & VT_VALMASK;
227 if (fr & VT_LVAL) {
228 if (v == VT_LLOCAL) {
229 v1.type.t = VT_INT;
230 v1.r = VT_LOCAL | VT_LVAL;
231 v1.c.ul = fc;
232 fr = r;
233 if (!(reg_classes[fr] & RC_INT))
234 fr = get_reg(RC_INT);
235 load(fr, &v1);
237 if ((ft & VT_BTYPE) == VT_FLOAT) {
238 o(0xd9); /* flds */
239 r = 0;
240 } else if ((ft & VT_BTYPE) == VT_DOUBLE) {
241 o(0xdd); /* fldl */
242 r = 0;
243 } else if ((ft & VT_BTYPE) == VT_LDOUBLE) {
244 o(0xdb); /* fldt */
245 r = 5;
246 } else if ((ft & VT_TYPE) == VT_BYTE) {
247 o(0xbe0f); /* movsbl */
248 } else if ((ft & VT_TYPE) == (VT_BYTE | VT_UNSIGNED)) {
249 o(0xb60f); /* movzbl */
250 } else if ((ft & VT_TYPE) == VT_SHORT) {
251 o(0xbf0f); /* movswl */
252 } else if ((ft & VT_TYPE) == (VT_SHORT | VT_UNSIGNED)) {
253 o(0xb70f); /* movzwl */
254 } else {
255 o(0x8b); /* movl */
257 gen_modrm(r, fr, sv->sym, fc);
258 } else {
259 if (v == VT_CONST) {
260 o(0xb8 + r); /* mov $xx, r */
261 gen_addr32(fr, sv->sym, fc);
262 } else if (v == VT_LOCAL) {
263 if (fc) {
264 o(0x8d); /* lea xxx(%ebp), r */
265 gen_modrm(r, VT_LOCAL, sv->sym, fc);
266 } else {
267 o(0x89);
268 o(0xe8 + r); /* mov %ebp, r */
270 } else if (v == VT_CMP) {
271 oad(0xb8 + r, 0); /* mov $0, r */
272 o(0x0f); /* setxx %br */
273 o(fc);
274 o(0xc0 + r);
275 } else if (v == VT_JMP || v == VT_JMPI) {
276 t = v & 1;
277 oad(0xb8 + r, t); /* mov $1, r */
278 o(0x05eb); /* jmp after */
279 gsym(fc);
280 oad(0xb8 + r, t ^ 1); /* mov $0, r */
281 } else if (v != r) {
282 o(0x89);
283 o(0xc0 + r + v * 8); /* mov v, r */
288 /* store register 'r' in lvalue 'v' */
289 ST_FUNC void store(int r, SValue *v)
291 int fr, bt, ft, fc;
293 #ifdef TCC_TARGET_PE
294 SValue v2;
295 v = pe_getimport(v, &v2);
296 #endif
298 ft = v->type.t;
299 fc = v->c.ul;
300 fr = v->r & VT_VALMASK;
301 bt = ft & VT_BTYPE;
302 /* XXX: incorrect if float reg to reg */
303 if (bt == VT_FLOAT) {
304 o(0xd9); /* fsts */
305 r = 2;
306 } else if (bt == VT_DOUBLE) {
307 o(0xdd); /* fstpl */
308 r = 2;
309 } else if (bt == VT_LDOUBLE) {
310 o(0xc0d9); /* fld %st(0) */
311 o(0xdb); /* fstpt */
312 r = 7;
313 } else {
314 if (bt == VT_SHORT)
315 o(0x66);
316 if (bt == VT_BYTE || bt == VT_BOOL)
317 o(0x88);
318 else
319 o(0x89);
321 if (fr == VT_CONST ||
322 fr == VT_LOCAL ||
323 (v->r & VT_LVAL)) {
324 gen_modrm(r, v->r, v->sym, fc);
325 } else if (fr != r) {
326 o(0xc0 + fr + r * 8); /* mov r, fr */
330 static void gadd_sp(int val)
332 if (val == (char)val) {
333 o(0xc483);
334 g(val);
335 } else {
336 oad(0xc481, val); /* add $xxx, %esp */
340 /* 'is_jmp' is '1' if it is a jump */
341 static void gcall_or_jmp(int is_jmp)
343 int r;
344 if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
345 /* constant case */
346 if (vtop->r & VT_SYM) {
347 /* relocation case */
348 greloc(cur_text_section, vtop->sym,
349 ind + 1, R_386_PC32);
350 } else {
351 /* put an empty PC32 relocation */
352 put_elf_reloc(symtab_section, cur_text_section,
353 ind + 1, R_386_PC32, 0);
355 oad(0xe8 + is_jmp, vtop->c.ul - 4); /* call/jmp im */
356 } else {
357 /* otherwise, indirect call */
358 r = gv(RC_INT);
359 o(0xff); /* call/jmp *r */
360 o(0xd0 + r + (is_jmp << 4));
364 static uint8_t fastcall_regs[3] = { TREG_EAX, TREG_EDX, TREG_ECX };
365 static uint8_t fastcallw_regs[2] = { TREG_ECX, TREG_EDX };
367 /* Generate function call. The function address is pushed first, then
368 all the parameters in call order. This functions pops all the
369 parameters and the function address. */
370 ST_FUNC void gfunc_call(int nb_args)
372 int size, align, r, args_size, i, func_call;
373 Sym *func_sym;
375 args_size = 0;
376 for(i = 0;i < nb_args; i++) {
377 if ((vtop->type.t & VT_BTYPE) == VT_STRUCT) {
378 size = type_size(&vtop->type, &align);
379 /* align to stack align size */
380 size = (size + 3) & ~3;
381 /* allocate the necessary size on stack */
382 oad(0xec81, size); /* sub $xxx, %esp */
383 /* generate structure store */
384 r = get_reg(RC_INT);
385 o(0x89); /* mov %esp, r */
386 o(0xe0 + r);
387 vset(&vtop->type, r | VT_LVAL, 0);
388 vswap();
389 vstore();
390 args_size += size;
391 } else if (is_float(vtop->type.t)) {
392 gv(RC_FLOAT); /* only one float register */
393 if ((vtop->type.t & VT_BTYPE) == VT_FLOAT)
394 size = 4;
395 else if ((vtop->type.t & VT_BTYPE) == VT_DOUBLE)
396 size = 8;
397 else
398 size = 12;
399 oad(0xec81, size); /* sub $xxx, %esp */
400 if (size == 12)
401 o(0x7cdb);
402 else
403 o(0x5cd9 + size - 4); /* fstp[s|l] 0(%esp) */
404 g(0x24);
405 g(0x00);
406 args_size += size;
407 } else {
408 /* simple type (currently always same size) */
409 /* XXX: implicit cast ? */
410 r = gv(RC_INT);
411 if ((vtop->type.t & VT_BTYPE) == VT_LLONG) {
412 size = 8;
413 o(0x50 + vtop->r2); /* push r */
414 } else {
415 size = 4;
417 o(0x50 + r); /* push r */
418 args_size += size;
420 vtop--;
422 save_regs(0); /* save used temporary registers */
423 func_sym = vtop->type.ref;
424 func_call = FUNC_CALL(func_sym->r);
425 /* fast call case */
426 if ((func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) ||
427 func_call == FUNC_FASTCALLW) {
428 int fastcall_nb_regs;
429 uint8_t *fastcall_regs_ptr;
430 if (func_call == FUNC_FASTCALLW) {
431 fastcall_regs_ptr = fastcallw_regs;
432 fastcall_nb_regs = 2;
433 } else {
434 fastcall_regs_ptr = fastcall_regs;
435 fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
437 for(i = 0;i < fastcall_nb_regs; i++) {
438 if (args_size <= 0)
439 break;
440 o(0x58 + fastcall_regs_ptr[i]); /* pop r */
441 /* XXX: incorrect for struct/floats */
442 args_size -= 4;
445 gcall_or_jmp(0);
447 #ifdef TCC_TARGET_PE
448 if ((func_sym->type.t & VT_BTYPE) == VT_STRUCT)
449 args_size -= 4;
450 #endif
451 if (args_size && func_call != FUNC_STDCALL)
452 gadd_sp(args_size);
453 vtop--;
456 #ifdef TCC_TARGET_PE
457 #define FUNC_PROLOG_SIZE 10
458 #else
459 #define FUNC_PROLOG_SIZE 9
460 #endif
462 /* generate function prolog of type 't' */
463 ST_FUNC void gfunc_prolog(CType *func_type)
465 int addr, align, size, func_call, fastcall_nb_regs;
466 int param_index, param_addr;
467 uint8_t *fastcall_regs_ptr;
468 Sym *sym;
469 CType *type;
471 sym = func_type->ref;
472 func_call = FUNC_CALL(sym->r);
473 addr = 8;
474 loc = 0;
475 func_vc = 0;
477 if (func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) {
478 fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
479 fastcall_regs_ptr = fastcall_regs;
480 } else if (func_call == FUNC_FASTCALLW) {
481 fastcall_nb_regs = 2;
482 fastcall_regs_ptr = fastcallw_regs;
483 } else {
484 fastcall_nb_regs = 0;
485 fastcall_regs_ptr = NULL;
487 param_index = 0;
489 ind += FUNC_PROLOG_SIZE;
490 func_sub_sp_offset = ind;
491 /* if the function returns a structure, then add an
492 implicit pointer parameter */
493 func_vt = sym->type;
494 if ((func_vt.t & VT_BTYPE) == VT_STRUCT) {
495 /* XXX: fastcall case ? */
496 func_vc = addr;
497 addr += 4;
498 param_index++;
500 /* define parameters */
501 while ((sym = sym->next) != NULL) {
502 type = &sym->type;
503 size = type_size(type, &align);
504 size = (size + 3) & ~3;
505 #ifdef FUNC_STRUCT_PARAM_AS_PTR
506 /* structs are passed as pointer */
507 if ((type->t & VT_BTYPE) == VT_STRUCT) {
508 size = 4;
510 #endif
511 if (param_index < fastcall_nb_regs) {
512 /* save FASTCALL register */
513 loc -= 4;
514 o(0x89); /* movl */
515 gen_modrm(fastcall_regs_ptr[param_index], VT_LOCAL, NULL, loc);
516 param_addr = loc;
517 } else {
518 param_addr = addr;
519 addr += size;
521 sym_push(sym->v & ~SYM_FIELD, type,
522 VT_LOCAL | lvalue_type(type->t), param_addr);
523 param_index++;
525 func_ret_sub = 0;
526 /* pascal type call ? */
527 if (func_call == FUNC_STDCALL)
528 func_ret_sub = addr - 8;
529 #ifdef TCC_TARGET_PE
530 else if (func_vc)
531 func_ret_sub = 4;
532 #endif
534 #ifdef CONFIG_TCC_BCHECK
535 /* leave some room for bound checking code */
536 if (tcc_state->do_bounds_check) {
537 oad(0xb8, 0); /* lbound section pointer */
538 oad(0xb8, 0); /* call to function */
539 func_bound_offset = lbounds_section->data_offset;
541 #endif
544 /* generate function epilog */
545 ST_FUNC void gfunc_epilog(void)
547 int v, saved_ind;
549 #ifdef CONFIG_TCC_BCHECK
550 if (tcc_state->do_bounds_check
551 && func_bound_offset != lbounds_section->data_offset) {
552 int saved_ind;
553 int *bounds_ptr;
554 Sym *sym, *sym_data;
555 /* add end of table info */
556 bounds_ptr = section_ptr_add(lbounds_section, sizeof(int));
557 *bounds_ptr = 0;
558 /* generate bound local allocation */
559 saved_ind = ind;
560 ind = func_sub_sp_offset;
561 sym_data = get_sym_ref(&char_pointer_type, lbounds_section,
562 func_bound_offset, lbounds_section->data_offset);
563 greloc(cur_text_section, sym_data,
564 ind + 1, R_386_32);
565 oad(0xb8, 0); /* mov %eax, xxx */
566 sym = external_global_sym(TOK___bound_local_new, &func_old_type, 0);
567 greloc(cur_text_section, sym,
568 ind + 1, R_386_PC32);
569 oad(0xe8, -4);
570 ind = saved_ind;
571 /* generate bound check local freeing */
572 o(0x5250); /* save returned value, if any */
573 greloc(cur_text_section, sym_data,
574 ind + 1, R_386_32);
575 oad(0xb8, 0); /* mov %eax, xxx */
576 sym = external_global_sym(TOK___bound_local_delete, &func_old_type, 0);
577 greloc(cur_text_section, sym,
578 ind + 1, R_386_PC32);
579 oad(0xe8, -4);
580 o(0x585a); /* restore returned value, if any */
582 #endif
583 o(0xc9); /* leave */
584 if (func_ret_sub == 0) {
585 o(0xc3); /* ret */
586 } else {
587 o(0xc2); /* ret n */
588 g(func_ret_sub);
589 g(func_ret_sub >> 8);
591 /* align local size to word & save local variables */
593 v = (-loc + 3) & -4;
594 saved_ind = ind;
595 ind = func_sub_sp_offset - FUNC_PROLOG_SIZE;
596 #ifdef TCC_TARGET_PE
597 if (v >= 4096) {
598 Sym *sym = external_global_sym(TOK___chkstk, &func_old_type, 0);
599 oad(0xb8, v); /* mov stacksize, %eax */
600 oad(0xe8, -4); /* call __chkstk, (does the stackframe too) */
601 greloc(cur_text_section, sym, ind-4, R_386_PC32);
602 } else
603 #endif
605 o(0xe58955); /* push %ebp, mov %esp, %ebp */
606 o(0xec81); /* sub esp, stacksize */
607 gen_le32(v);
608 #if FUNC_PROLOG_SIZE == 10
609 o(0x90); /* adjust to FUNC_PROLOG_SIZE */
610 #endif
612 ind = saved_ind;
615 /* generate a jump to a label */
616 ST_FUNC int gjmp(int t)
618 return psym(0xe9, t);
621 /* generate a jump to a fixed address */
622 ST_FUNC void gjmp_addr(int a)
624 int r;
625 r = a - ind - 2;
626 if (r == (char)r) {
627 g(0xeb);
628 g(r);
629 } else {
630 oad(0xe9, a - ind - 5);
634 /* generate a test. set 'inv' to invert test. Stack entry is popped */
635 ST_FUNC int gtst(int inv, int t)
637 int v, *p;
639 v = vtop->r & VT_VALMASK;
640 if (v == VT_CMP) {
641 /* fast case : can jump directly since flags are set */
642 g(0x0f);
643 t = psym((vtop->c.i - 16) ^ inv, t);
644 } else if (v == VT_JMP || v == VT_JMPI) {
645 /* && or || optimization */
646 if ((v & 1) == inv) {
647 /* insert vtop->c jump list in t */
648 p = &vtop->c.i;
649 while (*p != 0)
650 p = (int *)(cur_text_section->data + *p);
651 *p = t;
652 t = vtop->c.i;
653 } else {
654 t = gjmp(t);
655 gsym(vtop->c.i);
657 } else {
658 if (is_float(vtop->type.t) ||
659 (vtop->type.t & VT_BTYPE) == VT_LLONG) {
660 vpushi(0);
661 gen_op(TOK_NE);
663 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
664 /* constant jmp optimization */
665 if ((vtop->c.i != 0) != inv)
666 t = gjmp(t);
667 } else {
668 v = gv(RC_INT);
669 o(0x85);
670 o(0xc0 + v * 9);
671 g(0x0f);
672 t = psym(0x85 ^ inv, t);
675 vtop--;
676 return t;
679 /* generate an integer binary operation */
680 ST_FUNC void gen_opi(int op)
682 int r, fr, opc, c;
684 switch(op) {
685 case '+':
686 case TOK_ADDC1: /* add with carry generation */
687 opc = 0;
688 gen_op8:
689 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
690 /* constant case */
691 vswap();
692 r = gv(RC_INT);
693 vswap();
694 c = vtop->c.i;
695 if (c == (char)c) {
696 /* generate inc and dec for smaller code */
697 if (c==1 && opc==0) {
698 o (0x40 | r); // inc
699 } else if (c==1 && opc==5) {
700 o (0x48 | r); // dec
701 } else {
702 o(0x83);
703 o(0xc0 | (opc << 3) | r);
704 g(c);
706 } else {
707 o(0x81);
708 oad(0xc0 | (opc << 3) | r, c);
710 } else {
711 gv2(RC_INT, RC_INT);
712 r = vtop[-1].r;
713 fr = vtop[0].r;
714 o((opc << 3) | 0x01);
715 o(0xc0 + r + fr * 8);
717 vtop--;
718 if (op >= TOK_ULT && op <= TOK_GT) {
719 vtop->r = VT_CMP;
720 vtop->c.i = op;
722 break;
723 case '-':
724 case TOK_SUBC1: /* sub with carry generation */
725 opc = 5;
726 goto gen_op8;
727 case TOK_ADDC2: /* add with carry use */
728 opc = 2;
729 goto gen_op8;
730 case TOK_SUBC2: /* sub with carry use */
731 opc = 3;
732 goto gen_op8;
733 case '&':
734 opc = 4;
735 goto gen_op8;
736 case '^':
737 opc = 6;
738 goto gen_op8;
739 case '|':
740 opc = 1;
741 goto gen_op8;
742 case '*':
743 gv2(RC_INT, RC_INT);
744 r = vtop[-1].r;
745 fr = vtop[0].r;
746 vtop--;
747 o(0xaf0f); /* imul fr, r */
748 o(0xc0 + fr + r * 8);
749 break;
750 case TOK_SHL:
751 opc = 4;
752 goto gen_shift;
753 case TOK_SHR:
754 opc = 5;
755 goto gen_shift;
756 case TOK_SAR:
757 opc = 7;
758 gen_shift:
759 opc = 0xc0 | (opc << 3);
760 if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
761 /* constant case */
762 vswap();
763 r = gv(RC_INT);
764 vswap();
765 c = vtop->c.i & 0x1f;
766 o(0xc1); /* shl/shr/sar $xxx, r */
767 o(opc | r);
768 g(c);
769 } else {
770 /* we generate the shift in ecx */
771 gv2(RC_INT, RC_ECX);
772 r = vtop[-1].r;
773 o(0xd3); /* shl/shr/sar %cl, r */
774 o(opc | r);
776 vtop--;
777 break;
778 case '/':
779 case TOK_UDIV:
780 case TOK_PDIV:
781 case '%':
782 case TOK_UMOD:
783 case TOK_UMULL:
784 /* first operand must be in eax */
785 /* XXX: need better constraint for second operand */
786 gv2(RC_EAX, RC_ECX);
787 r = vtop[-1].r;
788 fr = vtop[0].r;
789 vtop--;
790 save_reg(TREG_EDX);
791 if (op == TOK_UMULL) {
792 o(0xf7); /* mul fr */
793 o(0xe0 + fr);
794 vtop->r2 = TREG_EDX;
795 r = TREG_EAX;
796 } else {
797 if (op == TOK_UDIV || op == TOK_UMOD) {
798 o(0xf7d231); /* xor %edx, %edx, div fr, %eax */
799 o(0xf0 + fr);
800 } else {
801 o(0xf799); /* cltd, idiv fr, %eax */
802 o(0xf8 + fr);
804 if (op == '%' || op == TOK_UMOD)
805 r = TREG_EDX;
806 else
807 r = TREG_EAX;
809 vtop->r = r;
810 break;
811 default:
812 opc = 7;
813 goto gen_op8;
817 /* generate a floating point operation 'v = t1 op t2' instruction. The
818 two operands are guaranted to have the same floating point type */
819 /* XXX: need to use ST1 too */
820 ST_FUNC void gen_opf(int op)
822 int a, ft, fc, swapped, r;
824 /* convert constants to memory references */
825 if ((vtop[-1].r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
826 vswap();
827 gv(RC_FLOAT);
828 vswap();
830 if ((vtop[0].r & (VT_VALMASK | VT_LVAL)) == VT_CONST)
831 gv(RC_FLOAT);
833 /* must put at least one value in the floating point register */
834 if ((vtop[-1].r & VT_LVAL) &&
835 (vtop[0].r & VT_LVAL)) {
836 vswap();
837 gv(RC_FLOAT);
838 vswap();
840 swapped = 0;
841 /* swap the stack if needed so that t1 is the register and t2 is
842 the memory reference */
843 if (vtop[-1].r & VT_LVAL) {
844 vswap();
845 swapped = 1;
847 if (op >= TOK_ULT && op <= TOK_GT) {
848 /* load on stack second operand */
849 load(TREG_ST0, vtop);
850 save_reg(TREG_EAX); /* eax is used by FP comparison code */
851 if (op == TOK_GE || op == TOK_GT)
852 swapped = !swapped;
853 else if (op == TOK_EQ || op == TOK_NE)
854 swapped = 0;
855 if (swapped)
856 o(0xc9d9); /* fxch %st(1) */
857 o(0xe9da); /* fucompp */
858 o(0xe0df); /* fnstsw %ax */
859 if (op == TOK_EQ) {
860 o(0x45e480); /* and $0x45, %ah */
861 o(0x40fC80); /* cmp $0x40, %ah */
862 } else if (op == TOK_NE) {
863 o(0x45e480); /* and $0x45, %ah */
864 o(0x40f480); /* xor $0x40, %ah */
865 op = TOK_NE;
866 } else if (op == TOK_GE || op == TOK_LE) {
867 o(0x05c4f6); /* test $0x05, %ah */
868 op = TOK_EQ;
869 } else {
870 o(0x45c4f6); /* test $0x45, %ah */
871 op = TOK_EQ;
873 vtop--;
874 vtop->r = VT_CMP;
875 vtop->c.i = op;
876 } else {
877 /* no memory reference possible for long double operations */
878 if ((vtop->type.t & VT_BTYPE) == VT_LDOUBLE) {
879 load(TREG_ST0, vtop);
880 swapped = !swapped;
883 switch(op) {
884 default:
885 case '+':
886 a = 0;
887 break;
888 case '-':
889 a = 4;
890 if (swapped)
891 a++;
892 break;
893 case '*':
894 a = 1;
895 break;
896 case '/':
897 a = 6;
898 if (swapped)
899 a++;
900 break;
902 ft = vtop->type.t;
903 fc = vtop->c.ul;
904 if ((ft & VT_BTYPE) == VT_LDOUBLE) {
905 o(0xde); /* fxxxp %st, %st(1) */
906 o(0xc1 + (a << 3));
907 } else {
908 /* if saved lvalue, then we must reload it */
909 r = vtop->r;
910 if ((r & VT_VALMASK) == VT_LLOCAL) {
911 SValue v1;
912 r = get_reg(RC_INT);
913 v1.type.t = VT_INT;
914 v1.r = VT_LOCAL | VT_LVAL;
915 v1.c.ul = fc;
916 load(r, &v1);
917 fc = 0;
920 if ((ft & VT_BTYPE) == VT_DOUBLE)
921 o(0xdc);
922 else
923 o(0xd8);
924 gen_modrm(a, r, vtop->sym, fc);
926 vtop--;
930 /* convert integers to fp 't' type. Must handle 'int', 'unsigned int'
931 and 'long long' cases. */
932 ST_FUNC void gen_cvt_itof(int t)
934 save_reg(TREG_ST0);
935 gv(RC_INT);
936 if ((vtop->type.t & VT_BTYPE) == VT_LLONG) {
937 /* signed long long to float/double/long double (unsigned case
938 is handled generically) */
939 o(0x50 + vtop->r2); /* push r2 */
940 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
941 o(0x242cdf); /* fildll (%esp) */
942 o(0x08c483); /* add $8, %esp */
943 } else if ((vtop->type.t & (VT_BTYPE | VT_UNSIGNED)) ==
944 (VT_INT | VT_UNSIGNED)) {
945 /* unsigned int to float/double/long double */
946 o(0x6a); /* push $0 */
947 g(0x00);
948 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
949 o(0x242cdf); /* fildll (%esp) */
950 o(0x08c483); /* add $8, %esp */
951 } else {
952 /* int to float/double/long double */
953 o(0x50 + (vtop->r & VT_VALMASK)); /* push r */
954 o(0x2404db); /* fildl (%esp) */
955 o(0x04c483); /* add $4, %esp */
957 vtop->r = TREG_ST0;
960 /* convert fp to int 't' type */
961 /* XXX: handle long long case */
962 ST_FUNC void gen_cvt_ftoi(int t)
964 int r, r2, size;
965 Sym *sym;
966 CType ushort_type;
968 ushort_type.t = VT_SHORT | VT_UNSIGNED;
969 ushort_type.ref = 0;
971 gv(RC_FLOAT);
972 if (t != VT_INT)
973 size = 8;
974 else
975 size = 4;
977 o(0x2dd9); /* ldcw xxx */
978 sym = external_global_sym(TOK___tcc_int_fpu_control,
979 &ushort_type, VT_LVAL);
980 greloc(cur_text_section, sym,
981 ind, R_386_32);
982 gen_le32(0);
984 oad(0xec81, size); /* sub $xxx, %esp */
985 if (size == 4)
986 o(0x1cdb); /* fistpl */
987 else
988 o(0x3cdf); /* fistpll */
989 o(0x24);
990 o(0x2dd9); /* ldcw xxx */
991 sym = external_global_sym(TOK___tcc_fpu_control,
992 &ushort_type, VT_LVAL);
993 greloc(cur_text_section, sym,
994 ind, R_386_32);
995 gen_le32(0);
997 r = get_reg(RC_INT);
998 o(0x58 + r); /* pop r */
999 if (size == 8) {
1000 if (t == VT_LLONG) {
1001 vtop->r = r; /* mark reg as used */
1002 r2 = get_reg(RC_INT);
1003 o(0x58 + r2); /* pop r2 */
1004 vtop->r2 = r2;
1005 } else {
1006 o(0x04c483); /* add $4, %esp */
1009 vtop->r = r;
1012 /* convert from one floating point type to another */
1013 ST_FUNC void gen_cvt_ftof(int t)
1015 /* all we have to do on i386 is to put the float in a register */
1016 gv(RC_FLOAT);
1019 /* computed goto support */
1020 ST_FUNC void ggoto(void)
1022 gcall_or_jmp(1);
1023 vtop--;
1026 /* bound check support functions */
1027 #ifdef CONFIG_TCC_BCHECK
1029 /* generate a bounded pointer addition */
1030 ST_FUNC void gen_bounded_ptr_add(void)
1032 Sym *sym;
1034 /* prepare fast i386 function call (args in eax and edx) */
1035 gv2(RC_EAX, RC_EDX);
1036 /* save all temporary registers */
1037 vtop -= 2;
1038 save_regs(0);
1039 /* do a fast function call */
1040 sym = external_global_sym(TOK___bound_ptr_add, &func_old_type, 0);
1041 greloc(cur_text_section, sym,
1042 ind + 1, R_386_PC32);
1043 oad(0xe8, -4);
1044 /* returned pointer is in eax */
1045 vtop++;
1046 vtop->r = TREG_EAX | VT_BOUNDED;
1047 /* address of bounding function call point */
1048 vtop->c.ul = (cur_text_section->reloc->data_offset - sizeof(Elf32_Rel));
1051 /* patch pointer addition in vtop so that pointer dereferencing is
1052 also tested */
1053 ST_FUNC void gen_bounded_ptr_deref(void)
1055 int func;
1056 int size, align;
1057 Elf32_Rel *rel;
1058 Sym *sym;
1060 size = 0;
1061 /* XXX: put that code in generic part of tcc */
1062 if (!is_float(vtop->type.t)) {
1063 if (vtop->r & VT_LVAL_BYTE)
1064 size = 1;
1065 else if (vtop->r & VT_LVAL_SHORT)
1066 size = 2;
1068 if (!size)
1069 size = type_size(&vtop->type, &align);
1070 switch(size) {
1071 case 1: func = TOK___bound_ptr_indir1; break;
1072 case 2: func = TOK___bound_ptr_indir2; break;
1073 case 4: func = TOK___bound_ptr_indir4; break;
1074 case 8: func = TOK___bound_ptr_indir8; break;
1075 case 12: func = TOK___bound_ptr_indir12; break;
1076 case 16: func = TOK___bound_ptr_indir16; break;
1077 default:
1078 tcc_error("unhandled size when dereferencing bounded pointer");
1079 func = 0;
1080 break;
1083 /* patch relocation */
1084 /* XXX: find a better solution ? */
1085 rel = (Elf32_Rel *)(cur_text_section->reloc->data + vtop->c.ul);
1086 sym = external_global_sym(func, &func_old_type, 0);
1087 if (!sym->c)
1088 put_extern_sym(sym, NULL, 0, 0);
1089 rel->r_info = ELF32_R_INFO(sym->c, ELF32_R_TYPE(rel->r_info));
1091 #endif
1093 /* end of X86 code generator */
1094 /*************************************************************/
1095 #endif
1096 /*************************************************************/