1 /*
2 * Stack-less Just-In-Time compiler
3 *
4 * Copyright 2009-2012 Zoltan Herczeg (hzmester@freemail.hu). All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without modification, are
7 * permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright notice, this list of
10 * conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
13 * of conditions and the following disclaimer in the documentation and/or other materials
14 * provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
19 * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
21 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
22 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
24 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 /* x86 32-bit arch dependent functions. */
28
emit_do_imm(struct sljit_compiler * compiler,sljit_ub opcode,sljit_sw imm)29 static sljit_si emit_do_imm(struct sljit_compiler *compiler, sljit_ub opcode, sljit_sw imm)
30 {
31 sljit_ub *inst;
32
33 inst = (sljit_ub*)ensure_buf(compiler, 1 + 1 + sizeof(sljit_sw));
34 FAIL_IF(!inst);
35 INC_SIZE(1 + sizeof(sljit_sw));
36 *inst++ = opcode;
37 *(sljit_sw*)inst = imm;
38 return SLJIT_SUCCESS;
39 }
40
generate_far_jump_code(struct sljit_jump * jump,sljit_ub * code_ptr,sljit_si type)41 static sljit_ub* generate_far_jump_code(struct sljit_jump *jump, sljit_ub *code_ptr, sljit_si type)
42 {
43 if (type == SLJIT_JUMP) {
44 *code_ptr++ = JMP_i32;
45 jump->addr++;
46 }
47 else if (type >= SLJIT_FAST_CALL) {
48 *code_ptr++ = CALL_i32;
49 jump->addr++;
50 }
51 else {
52 *code_ptr++ = GROUP_0F;
53 *code_ptr++ = get_jump_code(type);
54 jump->addr += 2;
55 }
56
57 if (jump->flags & JUMP_LABEL)
58 jump->flags |= PATCH_MW;
59 else
60 *(sljit_sw*)code_ptr = jump->u.target - (jump->addr + 4);
61 code_ptr += 4;
62
63 return code_ptr;
64 }
65
sljit_emit_enter(struct sljit_compiler * compiler,sljit_si options,sljit_si args,sljit_si scratches,sljit_si saveds,sljit_si fscratches,sljit_si fsaveds,sljit_si local_size)66 SLJIT_API_FUNC_ATTRIBUTE sljit_si sljit_emit_enter(struct sljit_compiler *compiler,
67 sljit_si options, sljit_si args, sljit_si scratches, sljit_si saveds,
68 sljit_si fscratches, sljit_si fsaveds, sljit_si local_size)
69 {
70 sljit_si size;
71 sljit_ub *inst;
72
73 CHECK_ERROR();
74 check_sljit_emit_enter(compiler, options, args, scratches, saveds, fscratches, fsaveds, local_size);
75
76 compiler->options = options;
77 compiler->scratches = scratches;
78 compiler->saveds = saveds;
79 compiler->fscratches = fscratches;
80 compiler->fsaveds = fsaveds;
81 compiler->args = args;
82 compiler->flags_saved = 0;
83 #if (defined SLJIT_DEBUG && SLJIT_DEBUG)
84 compiler->logical_local_size = local_size;
85 #endif
86
87 size = 1 + (scratches > 7 ? (scratches - 7) : 0) + (saveds <= 3 ? saveds : 3);
88 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
89 size += (args > 0 ? (args * 2) : 0) + (args > 2 ? 2 : 0);
90 #else
91 size += (args > 0 ? (2 + args * 3) : 0);
92 #endif
93 inst = (sljit_ub*)ensure_buf(compiler, 1 + size);
94 FAIL_IF(!inst);
95
96 INC_SIZE(size);
97 PUSH_REG(reg_map[TMP_REG1]);
98 #if !(defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
99 if (args > 0) {
100 *inst++ = MOV_r_rm;
101 *inst++ = MOD_REG | (reg_map[TMP_REG1] << 3) | 0x4 /* esp */;
102 }
103 #endif
104 if (saveds > 2 || scratches > 7)
105 PUSH_REG(reg_map[SLJIT_S2]);
106 if (saveds > 1 || scratches > 8)
107 PUSH_REG(reg_map[SLJIT_S1]);
108 if (saveds > 0 || scratches > 9)
109 PUSH_REG(reg_map[SLJIT_S0]);
110
111 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
112 if (args > 0) {
113 *inst++ = MOV_r_rm;
114 *inst++ = MOD_REG | (reg_map[SLJIT_S0] << 3) | reg_map[SLJIT_R2];
115 }
116 if (args > 1) {
117 *inst++ = MOV_r_rm;
118 *inst++ = MOD_REG | (reg_map[SLJIT_S1] << 3) | reg_map[SLJIT_R1];
119 }
120 if (args > 2) {
121 *inst++ = MOV_r_rm;
122 *inst++ = MOD_DISP8 | (reg_map[SLJIT_S2] << 3) | 0x4 /* esp */;
123 *inst++ = 0x24;
124 *inst++ = sizeof(sljit_sw) * (3 + 2); /* saveds >= 3 as well. */
125 }
126 #else
127 if (args > 0) {
128 *inst++ = MOV_r_rm;
129 *inst++ = MOD_DISP8 | (reg_map[SLJIT_S0] << 3) | reg_map[TMP_REG1];
130 *inst++ = sizeof(sljit_sw) * 2;
131 }
132 if (args > 1) {
133 *inst++ = MOV_r_rm;
134 *inst++ = MOD_DISP8 | (reg_map[SLJIT_S1] << 3) | reg_map[TMP_REG1];
135 *inst++ = sizeof(sljit_sw) * 3;
136 }
137 if (args > 2) {
138 *inst++ = MOV_r_rm;
139 *inst++ = MOD_DISP8 | (reg_map[SLJIT_S2] << 3) | reg_map[TMP_REG1];
140 *inst++ = sizeof(sljit_sw) * 4;
141 }
142 #endif
143
144 SLJIT_COMPILE_ASSERT(FIXED_LOCALS_OFFSET >= (2 + 4) * sizeof(sljit_uw), require_at_least_two_words);
145 #if defined(__APPLE__)
146 /* Ignore pushed registers and FIXED_LOCALS_OFFSET when
147 computing the aligned local size. */
148 saveds = (2 + (scratches > 7 ? (scratches - 7) : 0) + (saveds <= 3 ? saveds : 3)) * sizeof(sljit_uw);
149 local_size = ((FIXED_LOCALS_OFFSET + saveds + local_size + 15) & ~15) - saveds;
150 #else
151 local_size = FIXED_LOCALS_OFFSET + ((local_size + sizeof(sljit_uw) - 1) & ~(sizeof(sljit_uw) - 1));
152 #endif
153
154 compiler->local_size = local_size;
155 #ifdef _WIN32
156 if (local_size > 1024) {
157 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
158 FAIL_IF(emit_do_imm(compiler, MOV_r_i32 + reg_map[SLJIT_R0], local_size));
159 #else
160 local_size -= FIXED_LOCALS_OFFSET;
161 FAIL_IF(emit_do_imm(compiler, MOV_r_i32 + reg_map[SLJIT_R0], local_size));
162 FAIL_IF(emit_non_cum_binary(compiler, SUB_r_rm, SUB_rm_r, SUB, SUB_EAX_i32,
163 SLJIT_SP, 0, SLJIT_SP, 0, SLJIT_IMM, FIXED_LOCALS_OFFSET));
164 #endif
165 FAIL_IF(sljit_emit_ijump(compiler, SLJIT_CALL1, SLJIT_IMM, SLJIT_FUNC_OFFSET(sljit_grow_stack)));
166 }
167 #endif
168
169 SLJIT_ASSERT(local_size > 0);
170 return emit_non_cum_binary(compiler, SUB_r_rm, SUB_rm_r, SUB, SUB_EAX_i32,
171 SLJIT_SP, 0, SLJIT_SP, 0, SLJIT_IMM, local_size);
172 }
173
sljit_set_context(struct sljit_compiler * compiler,sljit_si options,sljit_si args,sljit_si scratches,sljit_si saveds,sljit_si fscratches,sljit_si fsaveds,sljit_si local_size)174 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_context(struct sljit_compiler *compiler,
175 sljit_si options, sljit_si args, sljit_si scratches, sljit_si saveds,
176 sljit_si fscratches, sljit_si fsaveds, sljit_si local_size)
177 {
178 CHECK_ERROR_VOID();
179 check_sljit_set_context(compiler, options, args, scratches, saveds, fscratches, fsaveds, local_size);
180
181 compiler->options = options;
182 compiler->scratches = scratches;
183 compiler->saveds = saveds;
184 compiler->fscratches = fscratches;
185 compiler->fsaveds = fsaveds;
186 compiler->args = args;
187 #if (defined SLJIT_DEBUG && SLJIT_DEBUG)
188 compiler->logical_local_size = local_size;
189 #endif
190
191 #if defined(__APPLE__)
192 saveds = (2 + (scratches > 7 ? (scratches - 7) : 0) + (saveds <= 3 ? saveds : 3)) * sizeof(sljit_uw);
193 compiler->local_size = ((FIXED_LOCALS_OFFSET + saveds + local_size + 15) & ~15) - saveds;
194 #else
195 compiler->local_size = FIXED_LOCALS_OFFSET + ((local_size + sizeof(sljit_uw) - 1) & ~(sizeof(sljit_uw) - 1));
196 #endif
197 }
198
sljit_emit_return(struct sljit_compiler * compiler,sljit_si op,sljit_si src,sljit_sw srcw)199 SLJIT_API_FUNC_ATTRIBUTE sljit_si sljit_emit_return(struct sljit_compiler *compiler, sljit_si op, sljit_si src, sljit_sw srcw)
200 {
201 sljit_si size;
202 sljit_ub *inst;
203
204 CHECK_ERROR();
205 check_sljit_emit_return(compiler, op, src, srcw);
206 SLJIT_ASSERT(compiler->args >= 0);
207
208 compiler->flags_saved = 0;
209 FAIL_IF(emit_mov_before_return(compiler, op, src, srcw));
210
211 SLJIT_ASSERT(compiler->local_size > 0);
212 FAIL_IF(emit_cum_binary(compiler, ADD_r_rm, ADD_rm_r, ADD, ADD_EAX_i32,
213 SLJIT_SP, 0, SLJIT_SP, 0, SLJIT_IMM, compiler->local_size));
214
215 size = 2 + (compiler->scratches > 7 ? (compiler->scratches - 7) : 0) +
216 (compiler->saveds <= 3 ? compiler->saveds : 3);
217 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
218 if (compiler->args > 2)
219 size += 2;
220 #else
221 if (compiler->args > 0)
222 size += 2;
223 #endif
224 inst = (sljit_ub*)ensure_buf(compiler, 1 + size);
225 FAIL_IF(!inst);
226
227 INC_SIZE(size);
228
229 if (compiler->saveds > 0 || compiler->scratches > 9)
230 POP_REG(reg_map[SLJIT_S0]);
231 if (compiler->saveds > 1 || compiler->scratches > 8)
232 POP_REG(reg_map[SLJIT_S1]);
233 if (compiler->saveds > 2 || compiler->scratches > 7)
234 POP_REG(reg_map[SLJIT_S2]);
235 POP_REG(reg_map[TMP_REG1]);
236 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
237 if (compiler->args > 2)
238 RET_I16(sizeof(sljit_sw));
239 else
240 RET();
241 #else
242 RET();
243 #endif
244
245 return SLJIT_SUCCESS;
246 }
247
248 /* --------------------------------------------------------------------- */
249 /* Operators */
250 /* --------------------------------------------------------------------- */
251
252 /* Size contains the flags as well. */
emit_x86_instruction(struct sljit_compiler * compiler,sljit_si size,sljit_si a,sljit_sw imma,sljit_si b,sljit_sw immb)253 static sljit_ub* emit_x86_instruction(struct sljit_compiler *compiler, sljit_si size,
254 /* The register or immediate operand. */
255 sljit_si a, sljit_sw imma,
256 /* The general operand (not immediate). */
257 sljit_si b, sljit_sw immb)
258 {
259 sljit_ub *inst;
260 sljit_ub *buf_ptr;
261 sljit_si flags = size & ~0xf;
262 sljit_si inst_size;
263
264 /* Both cannot be switched on. */
265 SLJIT_ASSERT((flags & (EX86_BIN_INS | EX86_SHIFT_INS)) != (EX86_BIN_INS | EX86_SHIFT_INS));
266 /* Size flags not allowed for typed instructions. */
267 SLJIT_ASSERT(!(flags & (EX86_BIN_INS | EX86_SHIFT_INS)) || (flags & (EX86_BYTE_ARG | EX86_HALF_ARG)) == 0);
268 /* Both size flags cannot be switched on. */
269 SLJIT_ASSERT((flags & (EX86_BYTE_ARG | EX86_HALF_ARG)) != (EX86_BYTE_ARG | EX86_HALF_ARG));
270 /* SSE2 and immediate is not possible. */
271 SLJIT_ASSERT(!(a & SLJIT_IMM) || !(flags & EX86_SSE2));
272 SLJIT_ASSERT((flags & (EX86_PREF_F2 | EX86_PREF_F3)) != (EX86_PREF_F2 | EX86_PREF_F3)
273 && (flags & (EX86_PREF_F2 | EX86_PREF_66)) != (EX86_PREF_F2 | EX86_PREF_66)
274 && (flags & (EX86_PREF_F3 | EX86_PREF_66)) != (EX86_PREF_F3 | EX86_PREF_66));
275
276 size &= 0xf;
277 inst_size = size;
278
279 if (flags & (EX86_PREF_F2 | EX86_PREF_F3))
280 inst_size++;
281 if (flags & EX86_PREF_66)
282 inst_size++;
283
284 /* Calculate size of b. */
285 inst_size += 1; /* mod r/m byte. */
286 if (b & SLJIT_MEM) {
287 if ((b & REG_MASK) == SLJIT_UNUSED)
288 inst_size += sizeof(sljit_sw);
289 else if (immb != 0 && !(b & OFFS_REG_MASK)) {
290 /* Immediate operand. */
291 if (immb <= 127 && immb >= -128)
292 inst_size += sizeof(sljit_sb);
293 else
294 inst_size += sizeof(sljit_sw);
295 }
296
297 if ((b & REG_MASK) == SLJIT_SP && !(b & OFFS_REG_MASK))
298 b |= TO_OFFS_REG(SLJIT_SP);
299
300 if ((b & OFFS_REG_MASK) != SLJIT_UNUSED)
301 inst_size += 1; /* SIB byte. */
302 }
303
304 /* Calculate size of a. */
305 if (a & SLJIT_IMM) {
306 if (flags & EX86_BIN_INS) {
307 if (imma <= 127 && imma >= -128) {
308 inst_size += 1;
309 flags |= EX86_BYTE_ARG;
310 } else
311 inst_size += 4;
312 }
313 else if (flags & EX86_SHIFT_INS) {
314 imma &= 0x1f;
315 if (imma != 1) {
316 inst_size ++;
317 flags |= EX86_BYTE_ARG;
318 }
319 } else if (flags & EX86_BYTE_ARG)
320 inst_size++;
321 else if (flags & EX86_HALF_ARG)
322 inst_size += sizeof(short);
323 else
324 inst_size += sizeof(sljit_sw);
325 }
326 else
327 SLJIT_ASSERT(!(flags & EX86_SHIFT_INS) || a == SLJIT_PREF_SHIFT_REG);
328
329 inst = (sljit_ub*)ensure_buf(compiler, 1 + inst_size);
330 PTR_FAIL_IF(!inst);
331
332 /* Encoding the byte. */
333 INC_SIZE(inst_size);
334 if (flags & EX86_PREF_F2)
335 *inst++ = 0xf2;
336 if (flags & EX86_PREF_F3)
337 *inst++ = 0xf3;
338 if (flags & EX86_PREF_66)
339 *inst++ = 0x66;
340
341 buf_ptr = inst + size;
342
343 /* Encode mod/rm byte. */
344 if (!(flags & EX86_SHIFT_INS)) {
345 if ((flags & EX86_BIN_INS) && (a & SLJIT_IMM))
346 *inst = (flags & EX86_BYTE_ARG) ? GROUP_BINARY_83 : GROUP_BINARY_81;
347
348 if ((a & SLJIT_IMM) || (a == 0))
349 *buf_ptr = 0;
350 else if (!(flags & EX86_SSE2_OP1))
351 *buf_ptr = reg_map[a] << 3;
352 else
353 *buf_ptr = a << 3;
354 }
355 else {
356 if (a & SLJIT_IMM) {
357 if (imma == 1)
358 *inst = GROUP_SHIFT_1;
359 else
360 *inst = GROUP_SHIFT_N;
361 } else
362 *inst = GROUP_SHIFT_CL;
363 *buf_ptr = 0;
364 }
365
366 if (!(b & SLJIT_MEM))
367 *buf_ptr++ |= MOD_REG + ((!(flags & EX86_SSE2_OP2)) ? reg_map[b] : b);
368 else if ((b & REG_MASK) != SLJIT_UNUSED) {
369 if ((b & OFFS_REG_MASK) == SLJIT_UNUSED || (b & OFFS_REG_MASK) == TO_OFFS_REG(SLJIT_SP)) {
370 if (immb != 0) {
371 if (immb <= 127 && immb >= -128)
372 *buf_ptr |= 0x40;
373 else
374 *buf_ptr |= 0x80;
375 }
376
377 if ((b & OFFS_REG_MASK) == SLJIT_UNUSED)
378 *buf_ptr++ |= reg_map[b & REG_MASK];
379 else {
380 *buf_ptr++ |= 0x04;
381 *buf_ptr++ = reg_map[b & REG_MASK] | (reg_map[OFFS_REG(b)] << 3);
382 }
383
384 if (immb != 0) {
385 if (immb <= 127 && immb >= -128)
386 *buf_ptr++ = immb; /* 8 bit displacement. */
387 else {
388 *(sljit_sw*)buf_ptr = immb; /* 32 bit displacement. */
389 buf_ptr += sizeof(sljit_sw);
390 }
391 }
392 }
393 else {
394 *buf_ptr++ |= 0x04;
395 *buf_ptr++ = reg_map[b & REG_MASK] | (reg_map[OFFS_REG(b)] << 3) | (immb << 6);
396 }
397 }
398 else {
399 *buf_ptr++ |= 0x05;
400 *(sljit_sw*)buf_ptr = immb; /* 32 bit displacement. */
401 buf_ptr += sizeof(sljit_sw);
402 }
403
404 if (a & SLJIT_IMM) {
405 if (flags & EX86_BYTE_ARG)
406 *buf_ptr = imma;
407 else if (flags & EX86_HALF_ARG)
408 *(short*)buf_ptr = imma;
409 else if (!(flags & EX86_SHIFT_INS))
410 *(sljit_sw*)buf_ptr = imma;
411 }
412
413 return !(flags & EX86_SHIFT_INS) ? inst : (inst + 1);
414 }
415
416 /* --------------------------------------------------------------------- */
417 /* Call / return instructions */
418 /* --------------------------------------------------------------------- */
419
call_with_args(struct sljit_compiler * compiler,sljit_si type)420 static SLJIT_INLINE sljit_si call_with_args(struct sljit_compiler *compiler, sljit_si type)
421 {
422 sljit_ub *inst;
423
424 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
425 inst = (sljit_ub*)ensure_buf(compiler, type >= SLJIT_CALL3 ? 1 + 2 + 1 : 1 + 2);
426 FAIL_IF(!inst);
427 INC_SIZE(type >= SLJIT_CALL3 ? 2 + 1 : 2);
428
429 if (type >= SLJIT_CALL3)
430 PUSH_REG(reg_map[SLJIT_R2]);
431 *inst++ = MOV_r_rm;
432 *inst++ = MOD_REG | (reg_map[SLJIT_R2] << 3) | reg_map[SLJIT_R0];
433 #else
434 inst = (sljit_ub*)ensure_buf(compiler, 1 + 4 * (type - SLJIT_CALL0));
435 FAIL_IF(!inst);
436 INC_SIZE(4 * (type - SLJIT_CALL0));
437
438 *inst++ = MOV_rm_r;
439 *inst++ = MOD_DISP8 | (reg_map[SLJIT_R0] << 3) | 0x4 /* SIB */;
440 *inst++ = (0x4 /* none*/ << 3) | reg_map[SLJIT_SP];
441 *inst++ = 0;
442 if (type >= SLJIT_CALL2) {
443 *inst++ = MOV_rm_r;
444 *inst++ = MOD_DISP8 | (reg_map[SLJIT_R1] << 3) | 0x4 /* SIB */;
445 *inst++ = (0x4 /* none*/ << 3) | reg_map[SLJIT_SP];
446 *inst++ = sizeof(sljit_sw);
447 }
448 if (type >= SLJIT_CALL3) {
449 *inst++ = MOV_rm_r;
450 *inst++ = MOD_DISP8 | (reg_map[SLJIT_R2] << 3) | 0x4 /* SIB */;
451 *inst++ = (0x4 /* none*/ << 3) | reg_map[SLJIT_SP];
452 *inst++ = 2 * sizeof(sljit_sw);
453 }
454 #endif
455 return SLJIT_SUCCESS;
456 }
457
sljit_emit_fast_enter(struct sljit_compiler * compiler,sljit_si dst,sljit_sw dstw)458 SLJIT_API_FUNC_ATTRIBUTE sljit_si sljit_emit_fast_enter(struct sljit_compiler *compiler, sljit_si dst, sljit_sw dstw)
459 {
460 sljit_ub *inst;
461
462 CHECK_ERROR();
463 check_sljit_emit_fast_enter(compiler, dst, dstw);
464 ADJUST_LOCAL_OFFSET(dst, dstw);
465
466 CHECK_EXTRA_REGS(dst, dstw, (void)0);
467
468 /* For UNUSED dst. Uncommon, but possible. */
469 if (dst == SLJIT_UNUSED)
470 dst = TMP_REG1;
471
472 if (FAST_IS_REG(dst)) {
473 /* Unused dest is possible here. */
474 inst = (sljit_ub*)ensure_buf(compiler, 1 + 1);
475 FAIL_IF(!inst);
476
477 INC_SIZE(1);
478 POP_REG(reg_map[dst]);
479 return SLJIT_SUCCESS;
480 }
481
482 /* Memory. */
483 inst = emit_x86_instruction(compiler, 1, 0, 0, dst, dstw);
484 FAIL_IF(!inst);
485 *inst++ = POP_rm;
486 return SLJIT_SUCCESS;
487 }
488
sljit_emit_fast_return(struct sljit_compiler * compiler,sljit_si src,sljit_sw srcw)489 SLJIT_API_FUNC_ATTRIBUTE sljit_si sljit_emit_fast_return(struct sljit_compiler *compiler, sljit_si src, sljit_sw srcw)
490 {
491 sljit_ub *inst;
492
493 CHECK_ERROR();
494 check_sljit_emit_fast_return(compiler, src, srcw);
495 ADJUST_LOCAL_OFFSET(src, srcw);
496
497 CHECK_EXTRA_REGS(src, srcw, (void)0);
498
499 if (FAST_IS_REG(src)) {
500 inst = (sljit_ub*)ensure_buf(compiler, 1 + 1 + 1);
501 FAIL_IF(!inst);
502
503 INC_SIZE(1 + 1);
504 PUSH_REG(reg_map[src]);
505 }
506 else if (src & SLJIT_MEM) {
507 inst = emit_x86_instruction(compiler, 1, 0, 0, src, srcw);
508 FAIL_IF(!inst);
509 *inst++ = GROUP_FF;
510 *inst |= PUSH_rm;
511
512 inst = (sljit_ub*)ensure_buf(compiler, 1 + 1);
513 FAIL_IF(!inst);
514 INC_SIZE(1);
515 }
516 else {
517 /* SLJIT_IMM. */
518 inst = (sljit_ub*)ensure_buf(compiler, 1 + 5 + 1);
519 FAIL_IF(!inst);
520
521 INC_SIZE(5 + 1);
522 *inst++ = PUSH_i32;
523 *(sljit_sw*)inst = srcw;
524 inst += sizeof(sljit_sw);
525 }
526
527 RET();
528 return SLJIT_SUCCESS;
529 }
530