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sljitNativeX86_32.c revision 1.2.2.4
      1 /*	$NetBSD: sljitNativeX86_32.c,v 1.2.2.4 2017/12/03 11:38:04 jdolecek Exp $	*/
      2 
      3 /*
      4  *    Stack-less Just-In-Time compiler
      5  *
      6  *    Copyright 2009-2012 Zoltan Herczeg (hzmester (at) freemail.hu). All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without modification, are
      9  * permitted provided that the following conditions are met:
     10  *
     11  *   1. Redistributions of source code must retain the above copyright notice, this list of
     12  *      conditions and the following disclaimer.
     13  *
     14  *   2. Redistributions in binary form must reproduce the above copyright notice, this list
     15  *      of conditions and the following disclaimer in the documentation and/or other materials
     16  *      provided with the distribution.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY
     19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
     21  * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
     22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
     23  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
     24  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
     26  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 /* x86 32-bit arch dependent functions. */
     30 
     31 static sljit_s32 emit_do_imm(struct sljit_compiler *compiler, sljit_u8 opcode, sljit_sw imm)
     32 {
     33 	sljit_u8 *inst;
     34 
     35 	inst = (sljit_u8*)ensure_buf(compiler, 1 + 1 + sizeof(sljit_sw));
     36 	FAIL_IF(!inst);
     37 	INC_SIZE(1 + sizeof(sljit_sw));
     38 	*inst++ = opcode;
     39 	*(sljit_sw*)inst = imm;
     40 	return SLJIT_SUCCESS;
     41 }
     42 
     43 static sljit_u8* generate_far_jump_code(struct sljit_jump *jump, sljit_u8 *code_ptr, sljit_s32 type)
     44 {
     45 	if (type == SLJIT_JUMP) {
     46 		*code_ptr++ = JMP_i32;
     47 		jump->addr++;
     48 	}
     49 	else if (type >= SLJIT_FAST_CALL) {
     50 		*code_ptr++ = CALL_i32;
     51 		jump->addr++;
     52 	}
     53 	else {
     54 		*code_ptr++ = GROUP_0F;
     55 		*code_ptr++ = get_jump_code(type);
     56 		jump->addr += 2;
     57 	}
     58 
     59 	if (jump->flags & JUMP_LABEL)
     60 		jump->flags |= PATCH_MW;
     61 	else
     62 		*(sljit_sw*)code_ptr = jump->u.target - (jump->addr + 4);
     63 	code_ptr += 4;
     64 
     65 	return code_ptr;
     66 }
     67 
     68 SLJIT_API_FUNC_ATTRIBUTE sljit_s32 sljit_emit_enter(struct sljit_compiler *compiler,
     69 	sljit_s32 options, sljit_s32 args, sljit_s32 scratches, sljit_s32 saveds,
     70 	sljit_s32 fscratches, sljit_s32 fsaveds, sljit_s32 local_size)
     71 {
     72 	sljit_s32 size;
     73 	sljit_u8 *inst;
     74 
     75 	CHECK_ERROR();
     76 	CHECK(check_sljit_emit_enter(compiler, options, args, scratches, saveds, fscratches, fsaveds, local_size));
     77 	set_emit_enter(compiler, options, args, scratches, saveds, fscratches, fsaveds, local_size);
     78 
     79 	compiler->args = args;
     80 	compiler->flags_saved = 0;
     81 
     82 	size = 1 + (scratches > 7 ? (scratches - 7) : 0) + (saveds <= 3 ? saveds : 3);
     83 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
     84 	size += (args > 0 ? (args * 2) : 0) + (args > 2 ? 2 : 0);
     85 #else
     86 	size += (args > 0 ? (2 + args * 3) : 0);
     87 #endif
     88 	inst = (sljit_u8*)ensure_buf(compiler, 1 + size);
     89 	FAIL_IF(!inst);
     90 
     91 	INC_SIZE(size);
     92 	PUSH_REG(reg_map[TMP_REG1]);
     93 #if !(defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
     94 	if (args > 0) {
     95 		*inst++ = MOV_r_rm;
     96 		*inst++ = MOD_REG | (reg_map[TMP_REG1] << 3) | 0x4 /* esp */;
     97 	}
     98 #endif
     99 	if (saveds > 2 || scratches > 7)
    100 		PUSH_REG(reg_map[SLJIT_S2]);
    101 	if (saveds > 1 || scratches > 8)
    102 		PUSH_REG(reg_map[SLJIT_S1]);
    103 	if (saveds > 0 || scratches > 9)
    104 		PUSH_REG(reg_map[SLJIT_S0]);
    105 
    106 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
    107 	if (args > 0) {
    108 		*inst++ = MOV_r_rm;
    109 		*inst++ = MOD_REG | (reg_map[SLJIT_S0] << 3) | reg_map[SLJIT_R2];
    110 	}
    111 	if (args > 1) {
    112 		*inst++ = MOV_r_rm;
    113 		*inst++ = MOD_REG | (reg_map[SLJIT_S1] << 3) | reg_map[SLJIT_R1];
    114 	}
    115 	if (args > 2) {
    116 		*inst++ = MOV_r_rm;
    117 		*inst++ = MOD_DISP8 | (reg_map[SLJIT_S2] << 3) | 0x4 /* esp */;
    118 		*inst++ = 0x24;
    119 		*inst++ = sizeof(sljit_sw) * (3 + 2); /* saveds >= 3 as well. */
    120 	}
    121 #else
    122 	if (args > 0) {
    123 		*inst++ = MOV_r_rm;
    124 		*inst++ = MOD_DISP8 | (reg_map[SLJIT_S0] << 3) | reg_map[TMP_REG1];
    125 		*inst++ = sizeof(sljit_sw) * 2;
    126 	}
    127 	if (args > 1) {
    128 		*inst++ = MOV_r_rm;
    129 		*inst++ = MOD_DISP8 | (reg_map[SLJIT_S1] << 3) | reg_map[TMP_REG1];
    130 		*inst++ = sizeof(sljit_sw) * 3;
    131 	}
    132 	if (args > 2) {
    133 		*inst++ = MOV_r_rm;
    134 		*inst++ = MOD_DISP8 | (reg_map[SLJIT_S2] << 3) | reg_map[TMP_REG1];
    135 		*inst++ = sizeof(sljit_sw) * 4;
    136 	}
    137 #endif
    138 
    139 	SLJIT_COMPILE_ASSERT(SLJIT_LOCALS_OFFSET >= (2 + 4) * sizeof(sljit_uw), require_at_least_two_words);
    140 #if defined(__APPLE__)
    141 	/* Ignore pushed registers and SLJIT_LOCALS_OFFSET when computing the aligned local size. */
    142 	saveds = (2 + (scratches > 7 ? (scratches - 7) : 0) + (saveds <= 3 ? saveds : 3)) * sizeof(sljit_uw);
    143 	local_size = ((SLJIT_LOCALS_OFFSET + saveds + local_size + 15) & ~15) - saveds;
    144 #else
    145 	if (options & SLJIT_DOUBLE_ALIGNMENT) {
    146 		local_size = SLJIT_LOCALS_OFFSET + ((local_size + 7) & ~7);
    147 
    148 		inst = (sljit_u8*)ensure_buf(compiler, 1 + 17);
    149 		FAIL_IF(!inst);
    150 
    151 		INC_SIZE(17);
    152 		inst[0] = MOV_r_rm;
    153 		inst[1] = MOD_REG | (reg_map[TMP_REG1] << 3) | reg_map[SLJIT_SP];
    154 		inst[2] = GROUP_F7;
    155 		inst[3] = MOD_REG | (0 << 3) | reg_map[SLJIT_SP];
    156 		*(sljit_sw*)(inst + 4) = 0x4;
    157 		inst[8] = JNE_i8;
    158 		inst[9] = 6;
    159 		inst[10] = GROUP_BINARY_81;
    160 		inst[11] = MOD_REG | (5 << 3) | reg_map[SLJIT_SP];
    161 		*(sljit_sw*)(inst + 12) = 0x4;
    162 		inst[16] = PUSH_r + reg_map[TMP_REG1];
    163 	}
    164 	else
    165 		local_size = SLJIT_LOCALS_OFFSET + ((local_size + 3) & ~3);
    166 #endif
    167 
    168 	compiler->local_size = local_size;
    169 #ifdef _WIN32
    170 	if (local_size > 1024) {
    171 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
    172 		FAIL_IF(emit_do_imm(compiler, MOV_r_i32 + reg_map[SLJIT_R0], local_size));
    173 #else
    174 		local_size -= SLJIT_LOCALS_OFFSET;
    175 		FAIL_IF(emit_do_imm(compiler, MOV_r_i32 + reg_map[SLJIT_R0], local_size));
    176 		FAIL_IF(emit_non_cum_binary(compiler, SUB_r_rm, SUB_rm_r, SUB, SUB_EAX_i32,
    177 			SLJIT_SP, 0, SLJIT_SP, 0, SLJIT_IMM, SLJIT_LOCALS_OFFSET));
    178 #endif
    179 		FAIL_IF(sljit_emit_ijump(compiler, SLJIT_CALL1, SLJIT_IMM, SLJIT_FUNC_OFFSET(sljit_grow_stack)));
    180 	}
    181 #endif
    182 
    183 	SLJIT_ASSERT(local_size > 0);
    184 	return emit_non_cum_binary(compiler, SUB_r_rm, SUB_rm_r, SUB, SUB_EAX_i32,
    185 		SLJIT_SP, 0, SLJIT_SP, 0, SLJIT_IMM, local_size);
    186 }
    187 
    188 SLJIT_API_FUNC_ATTRIBUTE sljit_s32 sljit_set_context(struct sljit_compiler *compiler,
    189 	sljit_s32 options, sljit_s32 args, sljit_s32 scratches, sljit_s32 saveds,
    190 	sljit_s32 fscratches, sljit_s32 fsaveds, sljit_s32 local_size)
    191 {
    192 	CHECK_ERROR();
    193 	CHECK(check_sljit_set_context(compiler, options, args, scratches, saveds, fscratches, fsaveds, local_size));
    194 	set_set_context(compiler, options, args, scratches, saveds, fscratches, fsaveds, local_size);
    195 
    196 	compiler->args = args;
    197 
    198 #if defined(__APPLE__)
    199 	saveds = (2 + (scratches > 7 ? (scratches - 7) : 0) + (saveds <= 3 ? saveds : 3)) * sizeof(sljit_uw);
    200 	compiler->local_size = ((SLJIT_LOCALS_OFFSET + saveds + local_size + 15) & ~15) - saveds;
    201 #else
    202 	if (options & SLJIT_DOUBLE_ALIGNMENT)
    203 		compiler->local_size = SLJIT_LOCALS_OFFSET + ((local_size + 7) & ~7);
    204 	else
    205 		compiler->local_size = SLJIT_LOCALS_OFFSET + ((local_size + 3) & ~3);
    206 #endif
    207 	return SLJIT_SUCCESS;
    208 }
    209 
    210 SLJIT_API_FUNC_ATTRIBUTE sljit_s32 sljit_emit_return(struct sljit_compiler *compiler, sljit_s32 op, sljit_s32 src, sljit_sw srcw)
    211 {
    212 	sljit_s32 size;
    213 	sljit_u8 *inst;
    214 
    215 	CHECK_ERROR();
    216 	CHECK(check_sljit_emit_return(compiler, op, src, srcw));
    217 	SLJIT_ASSERT(compiler->args >= 0);
    218 
    219 	compiler->flags_saved = 0;
    220 	FAIL_IF(emit_mov_before_return(compiler, op, src, srcw));
    221 
    222 	SLJIT_ASSERT(compiler->local_size > 0);
    223 	FAIL_IF(emit_cum_binary(compiler, ADD_r_rm, ADD_rm_r, ADD, ADD_EAX_i32,
    224 		SLJIT_SP, 0, SLJIT_SP, 0, SLJIT_IMM, compiler->local_size));
    225 
    226 #if !defined(__APPLE__)
    227 	if (compiler->options & SLJIT_DOUBLE_ALIGNMENT) {
    228 		inst = (sljit_u8*)ensure_buf(compiler, 1 + 3);
    229 		FAIL_IF(!inst);
    230 
    231 		INC_SIZE(3);
    232 		inst[0] = MOV_r_rm;
    233 		inst[1] = (reg_map[SLJIT_SP] << 3) | 0x4 /* SIB */;
    234 		inst[2] = (4 << 3) | reg_map[SLJIT_SP];
    235 	}
    236 #endif
    237 
    238 	size = 2 + (compiler->scratches > 7 ? (compiler->scratches - 7) : 0) +
    239 		(compiler->saveds <= 3 ? compiler->saveds : 3);
    240 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
    241 	if (compiler->args > 2)
    242 		size += 2;
    243 #else
    244 	if (compiler->args > 0)
    245 		size += 2;
    246 #endif
    247 	inst = (sljit_u8*)ensure_buf(compiler, 1 + size);
    248 	FAIL_IF(!inst);
    249 
    250 	INC_SIZE(size);
    251 
    252 	if (compiler->saveds > 0 || compiler->scratches > 9)
    253 		POP_REG(reg_map[SLJIT_S0]);
    254 	if (compiler->saveds > 1 || compiler->scratches > 8)
    255 		POP_REG(reg_map[SLJIT_S1]);
    256 	if (compiler->saveds > 2 || compiler->scratches > 7)
    257 		POP_REG(reg_map[SLJIT_S2]);
    258 	POP_REG(reg_map[TMP_REG1]);
    259 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
    260 	if (compiler->args > 2)
    261 		RET_I16(sizeof(sljit_sw));
    262 	else
    263 		RET();
    264 #else
    265 	RET();
    266 #endif
    267 
    268 	return SLJIT_SUCCESS;
    269 }
    270 
    271 /* --------------------------------------------------------------------- */
    272 /*  Operators                                                            */
    273 /* --------------------------------------------------------------------- */
    274 
    275 /* Size contains the flags as well. */
    276 static sljit_u8* emit_x86_instruction(struct sljit_compiler *compiler, sljit_s32 size,
    277 	/* The register or immediate operand. */
    278 	sljit_s32 a, sljit_sw imma,
    279 	/* The general operand (not immediate). */
    280 	sljit_s32 b, sljit_sw immb)
    281 {
    282 	sljit_u8 *inst;
    283 	sljit_u8 *buf_ptr;
    284 	sljit_s32 flags = size & ~0xf;
    285 	sljit_s32 inst_size;
    286 
    287 	/* Both cannot be switched on. */
    288 	SLJIT_ASSERT((flags & (EX86_BIN_INS | EX86_SHIFT_INS)) != (EX86_BIN_INS | EX86_SHIFT_INS));
    289 	/* Size flags not allowed for typed instructions. */
    290 	SLJIT_ASSERT(!(flags & (EX86_BIN_INS | EX86_SHIFT_INS)) || (flags & (EX86_BYTE_ARG | EX86_HALF_ARG)) == 0);
    291 	/* Both size flags cannot be switched on. */
    292 	SLJIT_ASSERT((flags & (EX86_BYTE_ARG | EX86_HALF_ARG)) != (EX86_BYTE_ARG | EX86_HALF_ARG));
    293 	/* SSE2 and immediate is not possible. */
    294 	SLJIT_ASSERT(!(a & SLJIT_IMM) || !(flags & EX86_SSE2));
    295 	SLJIT_ASSERT((flags & (EX86_PREF_F2 | EX86_PREF_F3)) != (EX86_PREF_F2 | EX86_PREF_F3)
    296 		&& (flags & (EX86_PREF_F2 | EX86_PREF_66)) != (EX86_PREF_F2 | EX86_PREF_66)
    297 		&& (flags & (EX86_PREF_F3 | EX86_PREF_66)) != (EX86_PREF_F3 | EX86_PREF_66));
    298 
    299 	size &= 0xf;
    300 	inst_size = size;
    301 
    302 	if (flags & (EX86_PREF_F2 | EX86_PREF_F3))
    303 		inst_size++;
    304 	if (flags & EX86_PREF_66)
    305 		inst_size++;
    306 
    307 	/* Calculate size of b. */
    308 	inst_size += 1; /* mod r/m byte. */
    309 	if (b & SLJIT_MEM) {
    310 		if ((b & REG_MASK) == SLJIT_UNUSED)
    311 			inst_size += sizeof(sljit_sw);
    312 		else if (immb != 0 && !(b & OFFS_REG_MASK)) {
    313 			/* Immediate operand. */
    314 			if (immb <= 127 && immb >= -128)
    315 				inst_size += sizeof(sljit_s8);
    316 			else
    317 				inst_size += sizeof(sljit_sw);
    318 		}
    319 
    320 		if ((b & REG_MASK) == SLJIT_SP && !(b & OFFS_REG_MASK))
    321 			b |= TO_OFFS_REG(SLJIT_SP);
    322 
    323 		if ((b & OFFS_REG_MASK) != SLJIT_UNUSED)
    324 			inst_size += 1; /* SIB byte. */
    325 	}
    326 
    327 	/* Calculate size of a. */
    328 	if (a & SLJIT_IMM) {
    329 		if (flags & EX86_BIN_INS) {
    330 			if (imma <= 127 && imma >= -128) {
    331 				inst_size += 1;
    332 				flags |= EX86_BYTE_ARG;
    333 			} else
    334 				inst_size += 4;
    335 		}
    336 		else if (flags & EX86_SHIFT_INS) {
    337 			imma &= 0x1f;
    338 			if (imma != 1) {
    339 				inst_size ++;
    340 				flags |= EX86_BYTE_ARG;
    341 			}
    342 		} else if (flags & EX86_BYTE_ARG)
    343 			inst_size++;
    344 		else if (flags & EX86_HALF_ARG)
    345 			inst_size += sizeof(short);
    346 		else
    347 			inst_size += sizeof(sljit_sw);
    348 	}
    349 	else
    350 		SLJIT_ASSERT(!(flags & EX86_SHIFT_INS) || a == SLJIT_PREF_SHIFT_REG);
    351 
    352 	inst = (sljit_u8*)ensure_buf(compiler, 1 + inst_size);
    353 	PTR_FAIL_IF(!inst);
    354 
    355 	/* Encoding the byte. */
    356 	INC_SIZE(inst_size);
    357 	if (flags & EX86_PREF_F2)
    358 		*inst++ = 0xf2;
    359 	if (flags & EX86_PREF_F3)
    360 		*inst++ = 0xf3;
    361 	if (flags & EX86_PREF_66)
    362 		*inst++ = 0x66;
    363 
    364 	buf_ptr = inst + size;
    365 
    366 	/* Encode mod/rm byte. */
    367 	if (!(flags & EX86_SHIFT_INS)) {
    368 		if ((flags & EX86_BIN_INS) && (a & SLJIT_IMM))
    369 			*inst = (flags & EX86_BYTE_ARG) ? GROUP_BINARY_83 : GROUP_BINARY_81;
    370 
    371 		if ((a & SLJIT_IMM) || (a == 0))
    372 			*buf_ptr = 0;
    373 		else if (!(flags & EX86_SSE2_OP1))
    374 			*buf_ptr = reg_map[a] << 3;
    375 		else
    376 			*buf_ptr = a << 3;
    377 	}
    378 	else {
    379 		if (a & SLJIT_IMM) {
    380 			if (imma == 1)
    381 				*inst = GROUP_SHIFT_1;
    382 			else
    383 				*inst = GROUP_SHIFT_N;
    384 		} else
    385 			*inst = GROUP_SHIFT_CL;
    386 		*buf_ptr = 0;
    387 	}
    388 
    389 	if (!(b & SLJIT_MEM))
    390 		*buf_ptr++ |= MOD_REG + ((!(flags & EX86_SSE2_OP2)) ? reg_map[b] : b);
    391 	else if ((b & REG_MASK) != SLJIT_UNUSED) {
    392 		if ((b & OFFS_REG_MASK) == SLJIT_UNUSED || (b & OFFS_REG_MASK) == TO_OFFS_REG(SLJIT_SP)) {
    393 			if (immb != 0) {
    394 				if (immb <= 127 && immb >= -128)
    395 					*buf_ptr |= 0x40;
    396 				else
    397 					*buf_ptr |= 0x80;
    398 			}
    399 
    400 			if ((b & OFFS_REG_MASK) == SLJIT_UNUSED)
    401 				*buf_ptr++ |= reg_map[b & REG_MASK];
    402 			else {
    403 				*buf_ptr++ |= 0x04;
    404 				*buf_ptr++ = reg_map[b & REG_MASK] | (reg_map[OFFS_REG(b)] << 3);
    405 			}
    406 
    407 			if (immb != 0) {
    408 				if (immb <= 127 && immb >= -128)
    409 					*buf_ptr++ = immb; /* 8 bit displacement. */
    410 				else {
    411 					*(sljit_sw*)buf_ptr = immb; /* 32 bit displacement. */
    412 					buf_ptr += sizeof(sljit_sw);
    413 				}
    414 			}
    415 		}
    416 		else {
    417 			*buf_ptr++ |= 0x04;
    418 			*buf_ptr++ = reg_map[b & REG_MASK] | (reg_map[OFFS_REG(b)] << 3) | (immb << 6);
    419 		}
    420 	}
    421 	else {
    422 		*buf_ptr++ |= 0x05;
    423 		*(sljit_sw*)buf_ptr = immb; /* 32 bit displacement. */
    424 		buf_ptr += sizeof(sljit_sw);
    425 	}
    426 
    427 	if (a & SLJIT_IMM) {
    428 		if (flags & EX86_BYTE_ARG)
    429 			*buf_ptr = imma;
    430 		else if (flags & EX86_HALF_ARG)
    431 			*(short*)buf_ptr = imma;
    432 		else if (!(flags & EX86_SHIFT_INS))
    433 			*(sljit_sw*)buf_ptr = imma;
    434 	}
    435 
    436 	return !(flags & EX86_SHIFT_INS) ? inst : (inst + 1);
    437 }
    438 
    439 /* --------------------------------------------------------------------- */
    440 /*  Call / return instructions                                           */
    441 /* --------------------------------------------------------------------- */
    442 
    443 static SLJIT_INLINE sljit_s32 call_with_args(struct sljit_compiler *compiler, sljit_s32 type)
    444 {
    445 	sljit_u8 *inst;
    446 
    447 #if (defined SLJIT_X86_32_FASTCALL && SLJIT_X86_32_FASTCALL)
    448 	inst = (sljit_u8*)ensure_buf(compiler, type >= SLJIT_CALL3 ? 1 + 2 + 1 : 1 + 2);
    449 	FAIL_IF(!inst);
    450 	INC_SIZE(type >= SLJIT_CALL3 ? 2 + 1 : 2);
    451 
    452 	if (type >= SLJIT_CALL3)
    453 		PUSH_REG(reg_map[SLJIT_R2]);
    454 	*inst++ = MOV_r_rm;
    455 	*inst++ = MOD_REG | (reg_map[SLJIT_R2] << 3) | reg_map[SLJIT_R0];
    456 #else
    457 	inst = (sljit_u8*)ensure_buf(compiler, 1 + 4 * (type - SLJIT_CALL0));
    458 	FAIL_IF(!inst);
    459 	INC_SIZE(4 * (type - SLJIT_CALL0));
    460 
    461 	*inst++ = MOV_rm_r;
    462 	*inst++ = MOD_DISP8 | (reg_map[SLJIT_R0] << 3) | 0x4 /* SIB */;
    463 	*inst++ = (0x4 /* none*/ << 3) | reg_map[SLJIT_SP];
    464 	*inst++ = 0;
    465 	if (type >= SLJIT_CALL2) {
    466 		*inst++ = MOV_rm_r;
    467 		*inst++ = MOD_DISP8 | (reg_map[SLJIT_R1] << 3) | 0x4 /* SIB */;
    468 		*inst++ = (0x4 /* none*/ << 3) | reg_map[SLJIT_SP];
    469 		*inst++ = sizeof(sljit_sw);
    470 	}
    471 	if (type >= SLJIT_CALL3) {
    472 		*inst++ = MOV_rm_r;
    473 		*inst++ = MOD_DISP8 | (reg_map[SLJIT_R2] << 3) | 0x4 /* SIB */;
    474 		*inst++ = (0x4 /* none*/ << 3) | reg_map[SLJIT_SP];
    475 		*inst++ = 2 * sizeof(sljit_sw);
    476 	}
    477 #endif
    478 	return SLJIT_SUCCESS;
    479 }
    480 
    481 SLJIT_API_FUNC_ATTRIBUTE sljit_s32 sljit_emit_fast_enter(struct sljit_compiler *compiler, sljit_s32 dst, sljit_sw dstw)
    482 {
    483 	sljit_u8 *inst;
    484 
    485 	CHECK_ERROR();
    486 	CHECK(check_sljit_emit_fast_enter(compiler, dst, dstw));
    487 	ADJUST_LOCAL_OFFSET(dst, dstw);
    488 
    489 	CHECK_EXTRA_REGS(dst, dstw, (void)0);
    490 
    491 	/* For UNUSED dst. Uncommon, but possible. */
    492 	if (dst == SLJIT_UNUSED)
    493 		dst = TMP_REG1;
    494 
    495 	if (FAST_IS_REG(dst)) {
    496 		/* Unused dest is possible here. */
    497 		inst = (sljit_u8*)ensure_buf(compiler, 1 + 1);
    498 		FAIL_IF(!inst);
    499 
    500 		INC_SIZE(1);
    501 		POP_REG(reg_map[dst]);
    502 		return SLJIT_SUCCESS;
    503 	}
    504 
    505 	/* Memory. */
    506 	inst = emit_x86_instruction(compiler, 1, 0, 0, dst, dstw);
    507 	FAIL_IF(!inst);
    508 	*inst++ = POP_rm;
    509 	return SLJIT_SUCCESS;
    510 }
    511 
    512 SLJIT_API_FUNC_ATTRIBUTE sljit_s32 sljit_emit_fast_return(struct sljit_compiler *compiler, sljit_s32 src, sljit_sw srcw)
    513 {
    514 	sljit_u8 *inst;
    515 
    516 	CHECK_ERROR();
    517 	CHECK(check_sljit_emit_fast_return(compiler, src, srcw));
    518 	ADJUST_LOCAL_OFFSET(src, srcw);
    519 
    520 	CHECK_EXTRA_REGS(src, srcw, (void)0);
    521 
    522 	if (FAST_IS_REG(src)) {
    523 		inst = (sljit_u8*)ensure_buf(compiler, 1 + 1 + 1);
    524 		FAIL_IF(!inst);
    525 
    526 		INC_SIZE(1 + 1);
    527 		PUSH_REG(reg_map[src]);
    528 	}
    529 	else if (src & SLJIT_MEM) {
    530 		inst = emit_x86_instruction(compiler, 1, 0, 0, src, srcw);
    531 		FAIL_IF(!inst);
    532 		*inst++ = GROUP_FF;
    533 		*inst |= PUSH_rm;
    534 
    535 		inst = (sljit_u8*)ensure_buf(compiler, 1 + 1);
    536 		FAIL_IF(!inst);
    537 		INC_SIZE(1);
    538 	}
    539 	else {
    540 		/* SLJIT_IMM. */
    541 		inst = (sljit_u8*)ensure_buf(compiler, 1 + 5 + 1);
    542 		FAIL_IF(!inst);
    543 
    544 		INC_SIZE(5 + 1);
    545 		*inst++ = PUSH_i32;
    546 		*(sljit_sw*)inst = srcw;
    547 		inst += sizeof(sljit_sw);
    548 	}
    549 
    550 	RET();
    551 	return SLJIT_SUCCESS;
    552 }
    553