1 /*
2  *    Stack-less Just-In-Time compiler
3  *
4  *    Copyright 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 /* mips 32-bit arch dependent functions. */
28 
load_immediate(struct sljit_compiler * compiler,sljit_s32 dst_ar,sljit_sw imm)29 static sljit_s32 load_immediate(struct sljit_compiler *compiler, sljit_s32 dst_ar, sljit_sw imm)
30 {
31 	if (!(imm & ~0xffff))
32 		return push_inst(compiler, ORI | SA(0) | TA(dst_ar) | IMM(imm), dst_ar);
33 
34 	if (imm < 0 && imm >= SIMM_MIN)
35 		return push_inst(compiler, ADDIU | SA(0) | TA(dst_ar) | IMM(imm), dst_ar);
36 
37 	FAIL_IF(push_inst(compiler, LUI | TA(dst_ar) | IMM(imm >> 16), dst_ar));
38 	return (imm & 0xffff) ? push_inst(compiler, ORI | SA(dst_ar) | TA(dst_ar) | IMM(imm), dst_ar) : SLJIT_SUCCESS;
39 }
40 
41 #define EMIT_LOGICAL(op_imm, op_norm) \
42 	if (flags & SRC2_IMM) { \
43 		if (op & SLJIT_SET_Z) \
44 			FAIL_IF(push_inst(compiler, op_imm | S(src1) | TA(EQUAL_FLAG) | IMM(src2), EQUAL_FLAG)); \
45 		if (!(flags & UNUSED_DEST)) \
46 			FAIL_IF(push_inst(compiler, op_imm | S(src1) | T(dst) | IMM(src2), DR(dst))); \
47 	} \
48 	else { \
49 		if (op & SLJIT_SET_Z) \
50 			FAIL_IF(push_inst(compiler, op_norm | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG)); \
51 		if (!(flags & UNUSED_DEST)) \
52 			FAIL_IF(push_inst(compiler, op_norm | S(src1) | T(src2) | D(dst), DR(dst))); \
53 	}
54 
55 #define EMIT_SHIFT(op_imm, op_v) \
56 	if (flags & SRC2_IMM) { \
57 		if (op & SLJIT_SET_Z) \
58 			FAIL_IF(push_inst(compiler, op_imm | T(src1) | DA(EQUAL_FLAG) | SH_IMM(src2), EQUAL_FLAG)); \
59 		if (!(flags & UNUSED_DEST)) \
60 			FAIL_IF(push_inst(compiler, op_imm | T(src1) | D(dst) | SH_IMM(src2), DR(dst))); \
61 	} \
62 	else { \
63 		if (op & SLJIT_SET_Z) \
64 			FAIL_IF(push_inst(compiler, op_v | S(src2) | T(src1) | DA(EQUAL_FLAG), EQUAL_FLAG)); \
65 		if (!(flags & UNUSED_DEST)) \
66 			FAIL_IF(push_inst(compiler, op_v | S(src2) | T(src1) | D(dst), DR(dst))); \
67 	}
68 
emit_single_op(struct sljit_compiler * compiler,sljit_s32 op,sljit_s32 flags,sljit_s32 dst,sljit_s32 src1,sljit_sw src2)69 static SLJIT_INLINE sljit_s32 emit_single_op(struct sljit_compiler *compiler, sljit_s32 op, sljit_s32 flags,
70 	sljit_s32 dst, sljit_s32 src1, sljit_sw src2)
71 {
72 	sljit_s32 is_overflow, is_carry, is_handled;
73 
74 	switch (GET_OPCODE(op)) {
75 	case SLJIT_MOV:
76 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
77 		if (dst != src2)
78 			return push_inst(compiler, ADDU | S(src2) | TA(0) | D(dst), DR(dst));
79 		return SLJIT_SUCCESS;
80 
81 	case SLJIT_MOV_U8:
82 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
83 		if ((flags & (REG_DEST | REG2_SOURCE)) == (REG_DEST | REG2_SOURCE))
84 			return push_inst(compiler, ANDI | S(src2) | T(dst) | IMM(0xff), DR(dst));
85 		SLJIT_ASSERT(dst == src2);
86 		return SLJIT_SUCCESS;
87 
88 	case SLJIT_MOV_S8:
89 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
90 		if ((flags & (REG_DEST | REG2_SOURCE)) == (REG_DEST | REG2_SOURCE)) {
91 #if (defined SLJIT_MIPS_REV && SLJIT_MIPS_REV >= 1)
92 			return push_inst(compiler, SEB | T(src2) | D(dst), DR(dst));
93 #else /* SLJIT_MIPS_REV < 1 */
94 			FAIL_IF(push_inst(compiler, SLL | T(src2) | D(dst) | SH_IMM(24), DR(dst)));
95 			return push_inst(compiler, SRA | T(dst) | D(dst) | SH_IMM(24), DR(dst));
96 #endif /* SLJIT_MIPS_REV >= 1 */
97 		}
98 		SLJIT_ASSERT(dst == src2);
99 		return SLJIT_SUCCESS;
100 
101 	case SLJIT_MOV_U16:
102 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
103 		if ((flags & (REG_DEST | REG2_SOURCE)) == (REG_DEST | REG2_SOURCE))
104 			return push_inst(compiler, ANDI | S(src2) | T(dst) | IMM(0xffff), DR(dst));
105 		SLJIT_ASSERT(dst == src2);
106 		return SLJIT_SUCCESS;
107 
108 	case SLJIT_MOV_S16:
109 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
110 		if ((flags & (REG_DEST | REG2_SOURCE)) == (REG_DEST | REG2_SOURCE)) {
111 #if (defined SLJIT_MIPS_REV && SLJIT_MIPS_REV >= 1)
112 			return push_inst(compiler, SEH | T(src2) | D(dst), DR(dst));
113 #else /* SLJIT_MIPS_REV < 1 */
114 			FAIL_IF(push_inst(compiler, SLL | T(src2) | D(dst) | SH_IMM(16), DR(dst)));
115 			return push_inst(compiler, SRA | T(dst) | D(dst) | SH_IMM(16), DR(dst));
116 #endif /* SLJIT_MIPS_REV >= 1 */
117 		}
118 		SLJIT_ASSERT(dst == src2);
119 		return SLJIT_SUCCESS;
120 
121 	case SLJIT_NOT:
122 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
123 		if (op & SLJIT_SET_Z)
124 			FAIL_IF(push_inst(compiler, NOR | S(src2) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
125 		if (!(flags & UNUSED_DEST))
126 			FAIL_IF(push_inst(compiler, NOR | S(src2) | T(src2) | D(dst), DR(dst)));
127 		return SLJIT_SUCCESS;
128 
129 	case SLJIT_CLZ:
130 		SLJIT_ASSERT(src1 == TMP_REG1 && !(flags & SRC2_IMM));
131 #if (defined SLJIT_MIPS_REV && SLJIT_MIPS_REV >= 1)
132 		if (op & SLJIT_SET_Z)
133 			FAIL_IF(push_inst(compiler, CLZ | S(src2) | TA(EQUAL_FLAG) | DA(EQUAL_FLAG), EQUAL_FLAG));
134 		if (!(flags & UNUSED_DEST))
135 			FAIL_IF(push_inst(compiler, CLZ | S(src2) | T(dst) | D(dst), DR(dst)));
136 #else /* SLJIT_MIPS_REV < 1 */
137 		if (SLJIT_UNLIKELY(flags & UNUSED_DEST)) {
138 			FAIL_IF(push_inst(compiler, SRL | T(src2) | DA(EQUAL_FLAG) | SH_IMM(31), EQUAL_FLAG));
139 			return push_inst(compiler, XORI | SA(EQUAL_FLAG) | TA(EQUAL_FLAG) | IMM(1), EQUAL_FLAG);
140 		}
141 		/* Nearly all instructions are unmovable in the following sequence. */
142 		FAIL_IF(push_inst(compiler, ADDU | S(src2) | TA(0) | D(TMP_REG1), DR(TMP_REG1)));
143 		/* Check zero. */
144 		FAIL_IF(push_inst(compiler, BEQ | S(TMP_REG1) | TA(0) | IMM(5), UNMOVABLE_INS));
145 		FAIL_IF(push_inst(compiler, ORI | SA(0) | T(dst) | IMM(32), UNMOVABLE_INS));
146 		FAIL_IF(push_inst(compiler, ADDIU | SA(0) | T(dst) | IMM(-1), DR(dst)));
147 		/* Loop for searching the highest bit. */
148 		FAIL_IF(push_inst(compiler, ADDIU | S(dst) | T(dst) | IMM(1), DR(dst)));
149 		FAIL_IF(push_inst(compiler, BGEZ | S(TMP_REG1) | IMM(-2), UNMOVABLE_INS));
150 		FAIL_IF(push_inst(compiler, SLL | T(TMP_REG1) | D(TMP_REG1) | SH_IMM(1), UNMOVABLE_INS));
151 #endif /* SLJIT_MIPS_REV >= 1 */
152 		return SLJIT_SUCCESS;
153 
154 	case SLJIT_ADD:
155 		is_overflow = GET_FLAG_TYPE(op) == SLJIT_OVERFLOW;
156 		is_carry = GET_FLAG_TYPE(op) == GET_FLAG_TYPE(SLJIT_SET_CARRY);
157 
158 		if (flags & SRC2_IMM) {
159 			if (is_overflow) {
160 				if (src2 >= 0)
161 					FAIL_IF(push_inst(compiler, OR | S(src1) | T(src1) | DA(EQUAL_FLAG), EQUAL_FLAG));
162 				else
163 					FAIL_IF(push_inst(compiler, NOR | S(src1) | T(src1) | DA(EQUAL_FLAG), EQUAL_FLAG));
164 			}
165 			else if (op & SLJIT_SET_Z)
166 				FAIL_IF(push_inst(compiler, ADDIU | S(src1) | TA(EQUAL_FLAG) | IMM(src2), EQUAL_FLAG));
167 
168 			if (is_overflow || is_carry) {
169 				if (src2 >= 0)
170 					FAIL_IF(push_inst(compiler, ORI | S(src1) | TA(OTHER_FLAG) | IMM(src2), OTHER_FLAG));
171 				else {
172 					FAIL_IF(push_inst(compiler, ADDIU | SA(0) | TA(OTHER_FLAG) | IMM(src2), OTHER_FLAG));
173 					FAIL_IF(push_inst(compiler, OR | S(src1) | TA(OTHER_FLAG) | DA(OTHER_FLAG), OTHER_FLAG));
174 				}
175 			}
176 			/* dst may be the same as src1 or src2. */
177 			if (!(flags & UNUSED_DEST) || (op & VARIABLE_FLAG_MASK))
178 				FAIL_IF(push_inst(compiler, ADDIU | S(src1) | T(dst) | IMM(src2), DR(dst)));
179 		}
180 		else {
181 			if (is_overflow)
182 				FAIL_IF(push_inst(compiler, XOR | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
183 			else if (op & SLJIT_SET_Z)
184 				FAIL_IF(push_inst(compiler, ADDU | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
185 
186 			if (is_overflow || is_carry)
187 				FAIL_IF(push_inst(compiler, OR | S(src1) | T(src2) | DA(OTHER_FLAG), OTHER_FLAG));
188 			/* dst may be the same as src1 or src2. */
189 			if (!(flags & UNUSED_DEST) || (op & VARIABLE_FLAG_MASK))
190 				FAIL_IF(push_inst(compiler, ADDU | S(src1) | T(src2) | D(dst), DR(dst)));
191 		}
192 
193 		/* a + b >= a | b (otherwise, the carry should be set to 1). */
194 		if (is_overflow || is_carry)
195 			FAIL_IF(push_inst(compiler, SLTU | S(dst) | TA(OTHER_FLAG) | DA(OTHER_FLAG), OTHER_FLAG));
196 		if (!is_overflow)
197 			return SLJIT_SUCCESS;
198 		FAIL_IF(push_inst(compiler, SLL | TA(OTHER_FLAG) | D(TMP_REG1) | SH_IMM(31), DR(TMP_REG1)));
199 		FAIL_IF(push_inst(compiler, XOR | S(TMP_REG1) | TA(EQUAL_FLAG) | DA(EQUAL_FLAG), EQUAL_FLAG));
200 		FAIL_IF(push_inst(compiler, XOR | S(dst) | TA(EQUAL_FLAG) | DA(OTHER_FLAG), OTHER_FLAG));
201 		if (op & SLJIT_SET_Z)
202 			FAIL_IF(push_inst(compiler, ADDU | S(dst) | TA(0) | DA(EQUAL_FLAG), EQUAL_FLAG));
203 		return push_inst(compiler, SRL | TA(OTHER_FLAG) | DA(OTHER_FLAG) | SH_IMM(31), OTHER_FLAG);
204 
205 	case SLJIT_ADDC:
206 		is_carry = GET_FLAG_TYPE(op) == GET_FLAG_TYPE(SLJIT_SET_CARRY);
207 
208 		if (flags & SRC2_IMM) {
209 			if (is_carry) {
210 				if (src2 >= 0)
211 					FAIL_IF(push_inst(compiler, ORI | S(src1) | TA(EQUAL_FLAG) | IMM(src2), EQUAL_FLAG));
212 				else {
213 					FAIL_IF(push_inst(compiler, ADDIU | SA(0) | TA(EQUAL_FLAG) | IMM(src2), EQUAL_FLAG));
214 					FAIL_IF(push_inst(compiler, OR | S(src1) | TA(EQUAL_FLAG) | DA(EQUAL_FLAG), EQUAL_FLAG));
215 				}
216 			}
217 			FAIL_IF(push_inst(compiler, ADDIU | S(src1) | T(dst) | IMM(src2), DR(dst)));
218 		} else {
219 			if (is_carry)
220 				FAIL_IF(push_inst(compiler, OR | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
221 			/* dst may be the same as src1 or src2. */
222 			FAIL_IF(push_inst(compiler, ADDU | S(src1) | T(src2) | D(dst), DR(dst)));
223 		}
224 		if (is_carry)
225 			FAIL_IF(push_inst(compiler, SLTU | S(dst) | TA(EQUAL_FLAG) | DA(EQUAL_FLAG), EQUAL_FLAG));
226 
227 		FAIL_IF(push_inst(compiler, ADDU | S(dst) | TA(OTHER_FLAG) | D(dst), DR(dst)));
228 		if (!is_carry)
229 			return SLJIT_SUCCESS;
230 
231 		/* Set ULESS_FLAG (dst == 0) && (OTHER_FLAG == 1). */
232 		FAIL_IF(push_inst(compiler, SLTU | S(dst) | TA(OTHER_FLAG) | DA(OTHER_FLAG), OTHER_FLAG));
233 		/* Set carry flag. */
234 		return push_inst(compiler, OR | SA(OTHER_FLAG) | TA(EQUAL_FLAG) | DA(OTHER_FLAG), OTHER_FLAG);
235 
236 	case SLJIT_SUB:
237 		if ((flags & SRC2_IMM) && src2 == SIMM_MIN) {
238 			FAIL_IF(push_inst(compiler, ADDIU | SA(0) | T(TMP_REG2) | IMM(src2), DR(TMP_REG2)));
239 			src2 = TMP_REG2;
240 			flags &= ~SRC2_IMM;
241 		}
242 
243 		is_handled = 0;
244 
245 		if (flags & SRC2_IMM) {
246 			if (GET_FLAG_TYPE(op) == SLJIT_LESS || GET_FLAG_TYPE(op) == SLJIT_GREATER_EQUAL) {
247 				FAIL_IF(push_inst(compiler, SLTIU | S(src1) | TA(OTHER_FLAG) | IMM(src2), OTHER_FLAG));
248 				is_handled = 1;
249 			}
250 			else if (GET_FLAG_TYPE(op) == SLJIT_SIG_LESS || GET_FLAG_TYPE(op) == SLJIT_SIG_GREATER_EQUAL) {
251 				FAIL_IF(push_inst(compiler, SLTI | S(src1) | TA(OTHER_FLAG) | IMM(src2), OTHER_FLAG));
252 				is_handled = 1;
253 			}
254 		}
255 
256 		if (!is_handled && GET_FLAG_TYPE(op) >= SLJIT_LESS && GET_FLAG_TYPE(op) <= SLJIT_SIG_LESS_EQUAL) {
257 			is_handled = 1;
258 
259 			if (flags & SRC2_IMM) {
260 				FAIL_IF(push_inst(compiler, ADDIU | SA(0) | T(TMP_REG2) | IMM(src2), DR(TMP_REG2)));
261 				src2 = TMP_REG2;
262 				flags &= ~SRC2_IMM;
263 			}
264 
265 			if (GET_FLAG_TYPE(op) == SLJIT_LESS || GET_FLAG_TYPE(op) == SLJIT_GREATER_EQUAL) {
266 				FAIL_IF(push_inst(compiler, SLTU | S(src1) | T(src2) | DA(OTHER_FLAG), OTHER_FLAG));
267 			}
268 			else if (GET_FLAG_TYPE(op) == SLJIT_GREATER || GET_FLAG_TYPE(op) == SLJIT_LESS_EQUAL)
269 			{
270 				FAIL_IF(push_inst(compiler, SLTU | S(src2) | T(src1) | DA(OTHER_FLAG), OTHER_FLAG));
271 			}
272 			else if (GET_FLAG_TYPE(op) == SLJIT_SIG_LESS || GET_FLAG_TYPE(op) == SLJIT_SIG_GREATER_EQUAL) {
273 				FAIL_IF(push_inst(compiler, SLT | S(src1) | T(src2) | DA(OTHER_FLAG), OTHER_FLAG));
274 			}
275 			else if (GET_FLAG_TYPE(op) == SLJIT_SIG_GREATER || GET_FLAG_TYPE(op) == SLJIT_SIG_LESS_EQUAL)
276 			{
277 				FAIL_IF(push_inst(compiler, SLT | S(src2) | T(src1) | DA(OTHER_FLAG), OTHER_FLAG));
278 			}
279 		}
280 
281 		if (is_handled) {
282 			if (flags & SRC2_IMM) {
283 				if (op & SLJIT_SET_Z)
284 					FAIL_IF(push_inst(compiler, ADDIU | S(src1) | TA(EQUAL_FLAG) | IMM(-src2), EQUAL_FLAG));
285 				if (!(flags & UNUSED_DEST))
286 					return push_inst(compiler, ADDIU | S(src1) | T(dst) | IMM(-src2), DR(dst));
287 			}
288 			else {
289 				if (op & SLJIT_SET_Z)
290 					FAIL_IF(push_inst(compiler, SUBU | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
291 				if (!(flags & UNUSED_DEST))
292 					return push_inst(compiler, SUBU | S(src1) | T(src2) | D(dst), DR(dst));
293 			}
294 			return SLJIT_SUCCESS;
295 		}
296 
297 		is_overflow = GET_FLAG_TYPE(op) == SLJIT_OVERFLOW;
298 		is_carry = GET_FLAG_TYPE(op) == GET_FLAG_TYPE(SLJIT_SET_CARRY);
299 
300 		if (flags & SRC2_IMM) {
301 			if (is_overflow) {
302 				if (src2 >= 0)
303 					FAIL_IF(push_inst(compiler, OR | S(src1) | T(src1) | DA(EQUAL_FLAG), EQUAL_FLAG));
304 				else
305 					FAIL_IF(push_inst(compiler, NOR | S(src1) | T(src1) | DA(EQUAL_FLAG), EQUAL_FLAG));
306 			}
307 			else if (op & SLJIT_SET_Z)
308 				FAIL_IF(push_inst(compiler, ADDIU | S(src1) | TA(EQUAL_FLAG) | IMM(-src2), EQUAL_FLAG));
309 
310 			if (is_overflow || is_carry)
311 				FAIL_IF(push_inst(compiler, SLTIU | S(src1) | TA(OTHER_FLAG) | IMM(src2), OTHER_FLAG));
312 			/* dst may be the same as src1 or src2. */
313 			if (!(flags & UNUSED_DEST) || (op & VARIABLE_FLAG_MASK))
314 				FAIL_IF(push_inst(compiler, ADDIU | S(src1) | T(dst) | IMM(-src2), DR(dst)));
315 		}
316 		else {
317 			if (is_overflow)
318 				FAIL_IF(push_inst(compiler, XOR | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
319 			else if (op & SLJIT_SET_Z)
320 				FAIL_IF(push_inst(compiler, SUBU | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
321 
322 			if (is_overflow || is_carry)
323 				FAIL_IF(push_inst(compiler, SLTU | S(src1) | T(src2) | DA(OTHER_FLAG), OTHER_FLAG));
324 			/* dst may be the same as src1 or src2. */
325 			if (!(flags & UNUSED_DEST) || (op & VARIABLE_FLAG_MASK))
326 				FAIL_IF(push_inst(compiler, SUBU | S(src1) | T(src2) | D(dst), DR(dst)));
327 		}
328 
329 		if (!is_overflow)
330 			return SLJIT_SUCCESS;
331 		FAIL_IF(push_inst(compiler, SLL | TA(OTHER_FLAG) | D(TMP_REG1) | SH_IMM(31), DR(TMP_REG1)));
332 		FAIL_IF(push_inst(compiler, XOR | S(TMP_REG1) | TA(EQUAL_FLAG) | DA(EQUAL_FLAG), EQUAL_FLAG));
333 		FAIL_IF(push_inst(compiler, XOR | S(dst) | TA(EQUAL_FLAG) | DA(OTHER_FLAG), OTHER_FLAG));
334 		if (op & SLJIT_SET_Z)
335 			FAIL_IF(push_inst(compiler, ADDU | S(dst) | TA(0) | DA(EQUAL_FLAG), EQUAL_FLAG));
336 		return push_inst(compiler, SRL | TA(OTHER_FLAG) | DA(OTHER_FLAG) | SH_IMM(31), OTHER_FLAG);
337 
338 	case SLJIT_SUBC:
339 		if ((flags & SRC2_IMM) && src2 == SIMM_MIN) {
340 			FAIL_IF(push_inst(compiler, ADDIU | SA(0) | T(TMP_REG2) | IMM(src2), DR(TMP_REG2)));
341 			src2 = TMP_REG2;
342 			flags &= ~SRC2_IMM;
343 		}
344 
345 		is_carry = GET_FLAG_TYPE(op) == GET_FLAG_TYPE(SLJIT_SET_CARRY);
346 
347 		if (flags & SRC2_IMM) {
348 			if (is_carry)
349 				FAIL_IF(push_inst(compiler, SLTIU | S(src1) | TA(EQUAL_FLAG) | IMM(src2), EQUAL_FLAG));
350 			/* dst may be the same as src1 or src2. */
351 			FAIL_IF(push_inst(compiler, ADDIU | S(src1) | T(dst) | IMM(-src2), DR(dst)));
352 		}
353 		else {
354 			if (is_carry)
355 				FAIL_IF(push_inst(compiler, SLTU | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
356 			/* dst may be the same as src1 or src2. */
357 			FAIL_IF(push_inst(compiler, SUBU | S(src1) | T(src2) | D(dst), DR(dst)));
358 		}
359 
360 		if (is_carry)
361 			FAIL_IF(push_inst(compiler, SLTU | S(dst) | TA(OTHER_FLAG) | D(TMP_REG1), DR(TMP_REG1)));
362 
363 		FAIL_IF(push_inst(compiler, SUBU | S(dst) | TA(OTHER_FLAG) | D(dst), DR(dst)));
364 		return (is_carry) ? push_inst(compiler, OR | SA(EQUAL_FLAG) | T(TMP_REG1) | DA(OTHER_FLAG), OTHER_FLAG) : SLJIT_SUCCESS;
365 
366 	case SLJIT_MUL:
367 		SLJIT_ASSERT(!(flags & SRC2_IMM));
368 
369 		if (GET_FLAG_TYPE(op) != SLJIT_OVERFLOW) {
370 #if (defined SLJIT_MIPS_REV && SLJIT_MIPS_REV >= 1)
371 			return push_inst(compiler, MUL | S(src1) | T(src2) | D(dst), DR(dst));
372 #else /* SLJIT_MIPS_REV < 1 */
373 			FAIL_IF(push_inst(compiler, MULT | S(src1) | T(src2), MOVABLE_INS));
374 			return push_inst(compiler, MFLO | D(dst), DR(dst));
375 #endif /* SLJIT_MIPS_REV >= 1 */
376 		}
377 
378 #if (defined SLJIT_MIPS_REV && SLJIT_MIPS_REV >= 6)
379 		FAIL_IF(push_inst(compiler, MUL | S(src1) | T(src2) | D(dst), DR(dst)));
380 		FAIL_IF(push_inst(compiler, MUH | S(src1) | T(src2) | DA(EQUAL_FLAG), EQUAL_FLAG));
381 #else /* SLJIT_MIPS_REV < 6 */
382 		FAIL_IF(push_inst(compiler, MULT | S(src1) | T(src2), MOVABLE_INS));
383 		FAIL_IF(push_inst(compiler, MFHI | DA(EQUAL_FLAG), EQUAL_FLAG));
384 		FAIL_IF(push_inst(compiler, MFLO | D(dst), DR(dst)));
385 #endif /* SLJIT_MIPS_REV >= 6 */
386 		FAIL_IF(push_inst(compiler, SRA | T(dst) | DA(OTHER_FLAG) | SH_IMM(31), OTHER_FLAG));
387 		return push_inst(compiler, SUBU | SA(EQUAL_FLAG) | TA(OTHER_FLAG) | DA(OTHER_FLAG), OTHER_FLAG);
388 
389 	case SLJIT_AND:
390 		EMIT_LOGICAL(ANDI, AND);
391 		return SLJIT_SUCCESS;
392 
393 	case SLJIT_OR:
394 		EMIT_LOGICAL(ORI, OR);
395 		return SLJIT_SUCCESS;
396 
397 	case SLJIT_XOR:
398 		EMIT_LOGICAL(XORI, XOR);
399 		return SLJIT_SUCCESS;
400 
401 	case SLJIT_SHL:
402 		EMIT_SHIFT(SLL, SLLV);
403 		return SLJIT_SUCCESS;
404 
405 	case SLJIT_LSHR:
406 		EMIT_SHIFT(SRL, SRLV);
407 		return SLJIT_SUCCESS;
408 
409 	case SLJIT_ASHR:
410 		EMIT_SHIFT(SRA, SRAV);
411 		return SLJIT_SUCCESS;
412 	}
413 
414 	SLJIT_UNREACHABLE();
415 	return SLJIT_SUCCESS;
416 }
417 
emit_const(struct sljit_compiler * compiler,sljit_s32 dst,sljit_sw init_value)418 static SLJIT_INLINE sljit_s32 emit_const(struct sljit_compiler *compiler, sljit_s32 dst, sljit_sw init_value)
419 {
420 	FAIL_IF(push_inst(compiler, LUI | T(dst) | IMM(init_value >> 16), DR(dst)));
421 	return push_inst(compiler, ORI | S(dst) | T(dst) | IMM(init_value), DR(dst));
422 }
423 
sljit_set_jump_addr(sljit_uw addr,sljit_uw new_target,sljit_sw executable_offset)424 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_jump_addr(sljit_uw addr, sljit_uw new_target, sljit_sw executable_offset)
425 {
426 	sljit_ins *inst = (sljit_ins *)addr;
427 	SLJIT_UNUSED_ARG(executable_offset);
428 
429 	SLJIT_UPDATE_WX_FLAGS(inst, inst + 2, 0);
430 	SLJIT_ASSERT((inst[0] & 0xffe00000) == LUI && (inst[1] & 0xfc000000) == ORI);
431 	inst[0] = (inst[0] & 0xffff0000) | ((new_target >> 16) & 0xffff);
432 	inst[1] = (inst[1] & 0xffff0000) | (new_target & 0xffff);
433 	SLJIT_UPDATE_WX_FLAGS(inst, inst + 2, 1);
434 	inst = (sljit_ins *)SLJIT_ADD_EXEC_OFFSET(inst, executable_offset);
435 	SLJIT_CACHE_FLUSH(inst, inst + 2);
436 }
437 
sljit_set_const(sljit_uw addr,sljit_sw new_constant,sljit_sw executable_offset)438 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_const(sljit_uw addr, sljit_sw new_constant, sljit_sw executable_offset)
439 {
440 	sljit_set_jump_addr(addr, (sljit_uw)new_constant, executable_offset);
441 }
442 
call_with_args(struct sljit_compiler * compiler,sljit_s32 arg_types,sljit_ins * ins_ptr,sljit_u32 * extra_space)443 static sljit_s32 call_with_args(struct sljit_compiler *compiler, sljit_s32 arg_types, sljit_ins *ins_ptr, sljit_u32 *extra_space)
444 {
445 	sljit_u32 is_tail_call = *extra_space & SLJIT_CALL_RETURN;
446 	sljit_u32 offset = 0;
447 	sljit_s32 float_arg_count = 0;
448 	sljit_s32 word_arg_count = 0;
449 	sljit_s32 types = 0;
450 	sljit_ins prev_ins = NOP;
451 	sljit_ins ins = NOP;
452 	sljit_u8 offsets[4];
453 	sljit_u8 *offsets_ptr = offsets;
454 
455 	SLJIT_ASSERT(reg_map[TMP_REG1] == 4 && freg_map[TMP_FREG1] == 12);
456 
457 	arg_types >>= SLJIT_ARG_SHIFT;
458 
459 	/* See ABI description in sljit_emit_enter. */
460 
461 	while (arg_types) {
462 		types = (types << SLJIT_ARG_SHIFT) | (arg_types & SLJIT_ARG_MASK);
463 		*offsets_ptr = (sljit_u8)offset;
464 
465 		switch (arg_types & SLJIT_ARG_MASK) {
466 		case SLJIT_ARG_TYPE_F64:
467 			if (offset & 0x7) {
468 				offset += sizeof(sljit_sw);
469 				*offsets_ptr = (sljit_u8)offset;
470 			}
471 
472 			if (word_arg_count == 0 && float_arg_count <= 1)
473 				*offsets_ptr = (sljit_u8)(254 + float_arg_count);
474 
475 			offset += sizeof(sljit_f64);
476 			float_arg_count++;
477 			break;
478 		case SLJIT_ARG_TYPE_F32:
479 			if (word_arg_count == 0 && float_arg_count <= 1)
480 				*offsets_ptr = (sljit_u8)(254 + float_arg_count);
481 
482 			offset += sizeof(sljit_f32);
483 			float_arg_count++;
484 			break;
485 		default:
486 			offset += sizeof(sljit_sw);
487 			word_arg_count++;
488 			break;
489 		}
490 
491 		arg_types >>= SLJIT_ARG_SHIFT;
492 		offsets_ptr++;
493 	}
494 
495 	/* Stack is aligned to 16 bytes. */
496 	SLJIT_ASSERT(offset <= 8 * sizeof(sljit_sw));
497 
498 	if (offset > 4 * sizeof(sljit_sw) && (!is_tail_call || offset > compiler->args_size)) {
499 		if (is_tail_call) {
500 			offset = (offset + sizeof(sljit_sw) + 15) & ~(sljit_uw)0xf;
501 			FAIL_IF(emit_stack_frame_release(compiler, (sljit_s32)offset, &prev_ins));
502 			*extra_space = offset;
503 		} else {
504 			FAIL_IF(push_inst(compiler, ADDIU | S(SLJIT_SP) | T(SLJIT_SP) | IMM(-16), DR(SLJIT_SP)));
505 			*extra_space = 16;
506 		}
507 	} else {
508 		if (is_tail_call)
509 			FAIL_IF(emit_stack_frame_release(compiler, 0, &prev_ins));
510 		*extra_space = 0;
511 	}
512 
513 	while (types) {
514 		--offsets_ptr;
515 
516 		switch (types & SLJIT_ARG_MASK) {
517 		case SLJIT_ARG_TYPE_F64:
518 			if (*offsets_ptr < 4 * sizeof (sljit_sw)) {
519 				if (prev_ins != NOP)
520 					FAIL_IF(push_inst(compiler, prev_ins, MOVABLE_INS));
521 
522 				/* Must be preceded by at least one other argument,
523 				 * and its starting offset must be 8 because of alignment. */
524 				SLJIT_ASSERT((*offsets_ptr >> 2) == 2);
525 
526 				prev_ins = MFC1 | TA(6) | FS(float_arg_count) | (1 << 11);
527 				ins = MFC1 | TA(7) | FS(float_arg_count);
528 			} else if (*offsets_ptr < 254)
529 				ins = SDC1 | S(SLJIT_SP) | FT(float_arg_count) | IMM(*offsets_ptr);
530 			else if (*offsets_ptr == 254)
531 				ins = MOV_S | FMT_D | FS(SLJIT_FR0) | FD(TMP_FREG1);
532 
533 			float_arg_count--;
534 			break;
535 		case SLJIT_ARG_TYPE_F32:
536 			if (*offsets_ptr < 4 * sizeof (sljit_sw))
537 				ins = MFC1 | TA(4 + (*offsets_ptr >> 2)) | FS(float_arg_count);
538 			else if (*offsets_ptr < 254)
539 				ins = SWC1 | S(SLJIT_SP) | FT(float_arg_count) | IMM(*offsets_ptr);
540 			else if (*offsets_ptr == 254)
541 				ins = MOV_S | FMT_S | FS(SLJIT_FR0) | FD(TMP_FREG1);
542 
543 			float_arg_count--;
544 			break;
545 		default:
546 			if (*offsets_ptr >= 4 * sizeof (sljit_sw))
547 				ins = SW | S(SLJIT_SP) | T(word_arg_count) | IMM(*offsets_ptr);
548 			else if ((*offsets_ptr >> 2) != word_arg_count - 1)
549 				ins = ADDU | S(word_arg_count) | TA(0) | DA(4 + (*offsets_ptr >> 2));
550 			else if (*offsets_ptr == 0)
551 				ins = ADDU | S(SLJIT_R0) | TA(0) | DA(4);
552 
553 			word_arg_count--;
554 			break;
555 		}
556 
557 		if (ins != NOP) {
558 			if (prev_ins != NOP)
559 				FAIL_IF(push_inst(compiler, prev_ins, MOVABLE_INS));
560 			prev_ins = ins;
561 			ins = NOP;
562 		}
563 
564 		types >>= SLJIT_ARG_SHIFT;
565 	}
566 
567 	*ins_ptr = prev_ins;
568 
569 	return SLJIT_SUCCESS;
570 }
571 
sljit_emit_call(struct sljit_compiler * compiler,sljit_s32 type,sljit_s32 arg_types)572 SLJIT_API_FUNC_ATTRIBUTE struct sljit_jump* sljit_emit_call(struct sljit_compiler *compiler, sljit_s32 type,
573 	sljit_s32 arg_types)
574 {
575 	struct sljit_jump *jump;
576 	sljit_u32 extra_space = (sljit_u32)type;
577 	sljit_ins ins;
578 
579 	CHECK_ERROR_PTR();
580 	CHECK_PTR(check_sljit_emit_call(compiler, type, arg_types));
581 
582 	jump = (struct sljit_jump*)ensure_abuf(compiler, sizeof(struct sljit_jump));
583 	PTR_FAIL_IF(!jump);
584 	set_jump(jump, compiler, type & SLJIT_REWRITABLE_JUMP);
585 
586 	PTR_FAIL_IF(call_with_args(compiler, arg_types, &ins, &extra_space));
587 
588 	SLJIT_ASSERT(DR(PIC_ADDR_REG) == 25 && PIC_ADDR_REG == TMP_REG2);
589 
590 	PTR_FAIL_IF(emit_const(compiler, PIC_ADDR_REG, 0));
591 
592 	if (!(type & SLJIT_CALL_RETURN) || extra_space > 0) {
593 		jump->flags |= IS_JAL | IS_CALL;
594 		PTR_FAIL_IF(push_inst(compiler, JALR | S(PIC_ADDR_REG) | DA(RETURN_ADDR_REG), UNMOVABLE_INS));
595 	} else
596 		PTR_FAIL_IF(push_inst(compiler, JR | S(PIC_ADDR_REG), UNMOVABLE_INS));
597 
598 	jump->addr = compiler->size;
599 	PTR_FAIL_IF(push_inst(compiler, ins, UNMOVABLE_INS));
600 
601 	if (extra_space == 0)
602 		return jump;
603 
604 	if (type & SLJIT_CALL_RETURN)
605 		PTR_FAIL_IF(emit_op_mem(compiler, WORD_DATA | LOAD_DATA, RETURN_ADDR_REG,
606 			SLJIT_MEM1(SLJIT_SP), (sljit_sw)(extra_space - sizeof(sljit_sw))));
607 
608 	if (type & SLJIT_CALL_RETURN)
609 		PTR_FAIL_IF(push_inst(compiler, JR | SA(RETURN_ADDR_REG), UNMOVABLE_INS));
610 
611 	PTR_FAIL_IF(push_inst(compiler, ADDIU | S(SLJIT_SP) | T(SLJIT_SP) | IMM(extra_space),
612 		(type & SLJIT_CALL_RETURN) ? UNMOVABLE_INS : DR(SLJIT_SP)));
613 	return jump;
614 }
615 
sljit_emit_icall(struct sljit_compiler * compiler,sljit_s32 type,sljit_s32 arg_types,sljit_s32 src,sljit_sw srcw)616 SLJIT_API_FUNC_ATTRIBUTE sljit_s32 sljit_emit_icall(struct sljit_compiler *compiler, sljit_s32 type,
617 	sljit_s32 arg_types,
618 	sljit_s32 src, sljit_sw srcw)
619 {
620 	sljit_u32 extra_space = (sljit_u32)type;
621 	sljit_ins ins;
622 
623 	CHECK_ERROR();
624 	CHECK(check_sljit_emit_icall(compiler, type, arg_types, src, srcw));
625 
626 	SLJIT_ASSERT(DR(PIC_ADDR_REG) == 25 && PIC_ADDR_REG == TMP_REG2);
627 
628 	if (src & SLJIT_IMM)
629 		FAIL_IF(load_immediate(compiler, DR(PIC_ADDR_REG), srcw));
630 	else if (FAST_IS_REG(src))
631 		FAIL_IF(push_inst(compiler, ADDU | S(src) | TA(0) | D(PIC_ADDR_REG), DR(PIC_ADDR_REG)));
632 	else if (src & SLJIT_MEM) {
633 		ADJUST_LOCAL_OFFSET(src, srcw);
634 		FAIL_IF(emit_op_mem(compiler, WORD_DATA | LOAD_DATA, DR(PIC_ADDR_REG), src, srcw));
635 	}
636 
637 	FAIL_IF(call_with_args(compiler, arg_types, &ins, &extra_space));
638 
639 	/* Register input. */
640 	if (!(type & SLJIT_CALL_RETURN) || extra_space > 0)
641 		FAIL_IF(push_inst(compiler, JALR | S(PIC_ADDR_REG) | DA(RETURN_ADDR_REG), UNMOVABLE_INS));
642 	else
643 		FAIL_IF(push_inst(compiler, JR | S(PIC_ADDR_REG), UNMOVABLE_INS));
644 	FAIL_IF(push_inst(compiler, ins, UNMOVABLE_INS));
645 
646 	if (extra_space == 0)
647 		return SLJIT_SUCCESS;
648 
649 	if (type & SLJIT_CALL_RETURN)
650 		FAIL_IF(emit_op_mem(compiler, WORD_DATA | LOAD_DATA, RETURN_ADDR_REG,
651 			SLJIT_MEM1(SLJIT_SP), (sljit_sw)(extra_space - sizeof(sljit_sw))));
652 
653 	if (type & SLJIT_CALL_RETURN)
654 		FAIL_IF(push_inst(compiler, JR | SA(RETURN_ADDR_REG), UNMOVABLE_INS));
655 
656 	return push_inst(compiler, ADDIU | S(SLJIT_SP) | T(SLJIT_SP) | IMM(extra_space),
657 		(type & SLJIT_CALL_RETURN) ? UNMOVABLE_INS : DR(SLJIT_SP));
658 }
659