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 /* ppc 32-bit arch dependent functions. */
28 
load_immediate(struct sljit_compiler * compiler,sljit_s32 reg,sljit_sw imm)29 static sljit_s32 load_immediate(struct sljit_compiler *compiler, sljit_s32 reg, sljit_sw imm)
30 {
31 	if (imm <= SIMM_MAX && imm >= SIMM_MIN)
32 		return push_inst(compiler, ADDI | D(reg) | A(0) | IMM(imm));
33 
34 	if (!(imm & ~0xffff))
35 		return push_inst(compiler, ORI | S(TMP_ZERO) | A(reg) | IMM(imm));
36 
37 	FAIL_IF(push_inst(compiler, ADDIS | D(reg) | A(0) | IMM(imm >> 16)));
38 	return (imm & 0xffff) ? push_inst(compiler, ORI | S(reg) | A(reg) | IMM(imm)) : SLJIT_SUCCESS;
39 }
40 
41 #define INS_CLEAR_LEFT(dst, src, from) \
42 	(RLWINM | S(src) | A(dst) | ((from) << 6) | (31 << 1))
43 
emit_single_op(struct sljit_compiler * compiler,sljit_s32 op,sljit_s32 flags,sljit_s32 dst,sljit_s32 src1,sljit_s32 src2)44 static SLJIT_INLINE sljit_s32 emit_single_op(struct sljit_compiler *compiler, sljit_s32 op, sljit_s32 flags,
45 	sljit_s32 dst, sljit_s32 src1, sljit_s32 src2)
46 {
47 	switch (op) {
48 	case SLJIT_MOV:
49 	case SLJIT_MOV_U32:
50 	case SLJIT_MOV_S32:
51 	case SLJIT_MOV_P:
52 		SLJIT_ASSERT(src1 == TMP_REG1);
53 		if (dst != src2)
54 			return push_inst(compiler, OR | S(src2) | A(dst) | B(src2));
55 		return SLJIT_SUCCESS;
56 
57 	case SLJIT_MOV_U8:
58 	case SLJIT_MOV_S8:
59 		SLJIT_ASSERT(src1 == TMP_REG1);
60 		if ((flags & (REG_DEST | REG2_SOURCE)) == (REG_DEST | REG2_SOURCE)) {
61 			if (op == SLJIT_MOV_S8)
62 				return push_inst(compiler, EXTSB | S(src2) | A(dst));
63 			return push_inst(compiler, INS_CLEAR_LEFT(dst, src2, 24));
64 		}
65 		else if ((flags & REG_DEST) && op == SLJIT_MOV_S8)
66 			return push_inst(compiler, EXTSB | S(src2) | A(dst));
67 		else {
68 			SLJIT_ASSERT(dst == src2);
69 		}
70 		return SLJIT_SUCCESS;
71 
72 	case SLJIT_MOV_U16:
73 	case SLJIT_MOV_S16:
74 		SLJIT_ASSERT(src1 == TMP_REG1);
75 		if ((flags & (REG_DEST | REG2_SOURCE)) == (REG_DEST | REG2_SOURCE)) {
76 			if (op == SLJIT_MOV_S16)
77 				return push_inst(compiler, EXTSH | S(src2) | A(dst));
78 			return push_inst(compiler, INS_CLEAR_LEFT(dst, src2, 16));
79 		}
80 		else {
81 			SLJIT_ASSERT(dst == src2);
82 		}
83 		return SLJIT_SUCCESS;
84 
85 	case SLJIT_NOT:
86 		SLJIT_ASSERT(src1 == TMP_REG1);
87 		return push_inst(compiler, NOR | RC(flags) | S(src2) | A(dst) | B(src2));
88 
89 	case SLJIT_NEG:
90 		SLJIT_ASSERT(src1 == TMP_REG1);
91 		/* Setting XER SO is not enough, CR SO is also needed. */
92 		return push_inst(compiler, NEG | OE((flags & ALT_FORM1) ? ALT_SET_FLAGS : 0) | RC(flags) | D(dst) | A(src2));
93 
94 	case SLJIT_CLZ:
95 		SLJIT_ASSERT(src1 == TMP_REG1);
96 		return push_inst(compiler, CNTLZW | S(src2) | A(dst));
97 
98 	case SLJIT_ADD:
99 		if (flags & ALT_FORM1) {
100 			/* Setting XER SO is not enough, CR SO is also needed. */
101 			return push_inst(compiler, ADD | OE(ALT_SET_FLAGS) | RC(ALT_SET_FLAGS) | D(dst) | A(src1) | B(src2));
102 		}
103 
104 		if (flags & ALT_FORM2) {
105 			/* Flags does not set: BIN_IMM_EXTS unnecessary. */
106 			SLJIT_ASSERT(src2 == TMP_REG2);
107 
108 			if (flags & ALT_FORM3)
109 				return push_inst(compiler, ADDIS | D(dst) | A(src1) | compiler->imm);
110 
111 			if (flags & ALT_FORM4) {
112 				FAIL_IF(push_inst(compiler, ADDIS | D(dst) | A(src1) | (((compiler->imm >> 16) & 0xffff) + ((compiler->imm >> 15) & 0x1))));
113 				src1 = dst;
114 			}
115 
116 			return push_inst(compiler, ADDI | D(dst) | A(src1) | (compiler->imm & 0xffff));
117 		}
118 		if (flags & ALT_FORM3) {
119 			SLJIT_ASSERT(src2 == TMP_REG2);
120 			return push_inst(compiler, ADDIC | D(dst) | A(src1) | compiler->imm);
121 		}
122 		if (!(flags & ALT_SET_FLAGS))
123 			return push_inst(compiler, ADD | D(dst) | A(src1) | B(src2));
124 		if (flags & ALT_FORM4)
125 			return push_inst(compiler, ADDC | RC(ALT_SET_FLAGS) | D(dst) | A(src1) | B(src2));
126 		return push_inst(compiler, ADD | RC(flags) | D(dst) | A(src1) | B(src2));
127 
128 	case SLJIT_ADDC:
129 		return push_inst(compiler, ADDE | D(dst) | A(src1) | B(src2));
130 
131 	case SLJIT_SUB:
132 		if (flags & ALT_FORM1) {
133 			if (flags & ALT_FORM2) {
134 				FAIL_IF(push_inst(compiler, CMPLI | CRD(0) | A(src1) | compiler->imm));
135 				if (!(flags & ALT_FORM3))
136 					return SLJIT_SUCCESS;
137 				return push_inst(compiler, ADDI | D(dst) | A(src1) | (-compiler->imm & 0xffff));
138 			}
139 			FAIL_IF(push_inst(compiler, CMPL | CRD(0) | A(src1) | B(src2)));
140 			if (!(flags & ALT_FORM3))
141 				return SLJIT_SUCCESS;
142 			return push_inst(compiler, SUBF | D(dst) | A(src2) | B(src1));
143 		}
144 
145 		if (flags & ALT_FORM2) {
146 			/* Setting XER SO is not enough, CR SO is also needed. */
147 			return push_inst(compiler, SUBF | OE(ALT_SET_FLAGS) | RC(ALT_SET_FLAGS) | D(dst) | A(src2) | B(src1));
148 		}
149 
150 		if (flags & ALT_FORM3) {
151 			/* Flags does not set: BIN_IMM_EXTS unnecessary. */
152 			SLJIT_ASSERT(src2 == TMP_REG2);
153 			return push_inst(compiler, SUBFIC | D(dst) | A(src1) | compiler->imm);
154 		}
155 
156 		if (flags & ALT_FORM4) {
157 			if (flags & ALT_FORM5) {
158 				SLJIT_ASSERT(src2 == TMP_REG2);
159 				return push_inst(compiler, CMPI | CRD(0) | A(src1) | compiler->imm);
160 			}
161 			return push_inst(compiler, CMP | CRD(0) | A(src1) | B(src2));
162 		}
163 
164 		if (!(flags & ALT_SET_FLAGS))
165 			return push_inst(compiler, SUBF | D(dst) | A(src2) | B(src1));
166 		if (flags & ALT_FORM5)
167 			return push_inst(compiler, SUBFC | RC(ALT_SET_FLAGS) | D(dst) | A(src2) | B(src1));
168 		return push_inst(compiler, SUBF | RC(flags) | D(dst) | A(src2) | B(src1));
169 
170 	case SLJIT_SUBC:
171 		return push_inst(compiler, SUBFE | D(dst) | A(src2) | B(src1));
172 
173 	case SLJIT_MUL:
174 		if (flags & ALT_FORM1) {
175 			SLJIT_ASSERT(src2 == TMP_REG2);
176 			return push_inst(compiler, MULLI | D(dst) | A(src1) | compiler->imm);
177 		}
178 		return push_inst(compiler, MULLW | OE(flags) | RC(flags) | D(dst) | A(src2) | B(src1));
179 
180 	case SLJIT_AND:
181 		if (flags & ALT_FORM1) {
182 			SLJIT_ASSERT(src2 == TMP_REG2);
183 			return push_inst(compiler, ANDI | S(src1) | A(dst) | compiler->imm);
184 		}
185 		if (flags & ALT_FORM2) {
186 			SLJIT_ASSERT(src2 == TMP_REG2);
187 			return push_inst(compiler, ANDIS | S(src1) | A(dst) | compiler->imm);
188 		}
189 		return push_inst(compiler, AND | RC(flags) | S(src1) | A(dst) | B(src2));
190 
191 	case SLJIT_OR:
192 		if (flags & ALT_FORM1) {
193 			SLJIT_ASSERT(src2 == TMP_REG2);
194 			return push_inst(compiler, ORI | S(src1) | A(dst) | compiler->imm);
195 		}
196 		if (flags & ALT_FORM2) {
197 			SLJIT_ASSERT(src2 == TMP_REG2);
198 			return push_inst(compiler, ORIS | S(src1) | A(dst) | compiler->imm);
199 		}
200 		if (flags & ALT_FORM3) {
201 			SLJIT_ASSERT(src2 == TMP_REG2);
202 			FAIL_IF(push_inst(compiler, ORI | S(src1) | A(dst) | IMM(compiler->imm)));
203 			return push_inst(compiler, ORIS | S(dst) | A(dst) | IMM(compiler->imm >> 16));
204 		}
205 		return push_inst(compiler, OR | RC(flags) | S(src1) | A(dst) | B(src2));
206 
207 	case SLJIT_XOR:
208 		if (flags & ALT_FORM1) {
209 			SLJIT_ASSERT(src2 == TMP_REG2);
210 			return push_inst(compiler, XORI | S(src1) | A(dst) | compiler->imm);
211 		}
212 		if (flags & ALT_FORM2) {
213 			SLJIT_ASSERT(src2 == TMP_REG2);
214 			return push_inst(compiler, XORIS | S(src1) | A(dst) | compiler->imm);
215 		}
216 		if (flags & ALT_FORM3) {
217 			SLJIT_ASSERT(src2 == TMP_REG2);
218 			FAIL_IF(push_inst(compiler, XORI | S(src1) | A(dst) | IMM(compiler->imm)));
219 			return push_inst(compiler, XORIS | S(dst) | A(dst) | IMM(compiler->imm >> 16));
220 		}
221 		return push_inst(compiler, XOR | RC(flags) | S(src1) | A(dst) | B(src2));
222 
223 	case SLJIT_SHL:
224 		if (flags & ALT_FORM1) {
225 			SLJIT_ASSERT(src2 == TMP_REG2);
226 			compiler->imm &= 0x1f;
227 			return push_inst(compiler, RLWINM | RC(flags) | S(src1) | A(dst) | (compiler->imm << 11) | ((31 - compiler->imm) << 1));
228 		}
229 		return push_inst(compiler, SLW | RC(flags) | S(src1) | A(dst) | B(src2));
230 
231 	case SLJIT_LSHR:
232 		if (flags & ALT_FORM1) {
233 			SLJIT_ASSERT(src2 == TMP_REG2);
234 			compiler->imm &= 0x1f;
235 			return push_inst(compiler, RLWINM | RC(flags) | S(src1) | A(dst) | (((32 - compiler->imm) & 0x1f) << 11) | (compiler->imm << 6) | (31 << 1));
236 		}
237 		return push_inst(compiler, SRW | RC(flags) | S(src1) | A(dst) | B(src2));
238 
239 	case SLJIT_ASHR:
240 		if (flags & ALT_FORM1) {
241 			SLJIT_ASSERT(src2 == TMP_REG2);
242 			compiler->imm &= 0x1f;
243 			return push_inst(compiler, SRAWI | RC(flags) | S(src1) | A(dst) | (compiler->imm << 11));
244 		}
245 		return push_inst(compiler, SRAW | RC(flags) | S(src1) | A(dst) | B(src2));
246 	}
247 
248 	SLJIT_UNREACHABLE();
249 	return SLJIT_SUCCESS;
250 }
251 
emit_const(struct sljit_compiler * compiler,sljit_s32 reg,sljit_sw init_value)252 static SLJIT_INLINE sljit_s32 emit_const(struct sljit_compiler *compiler, sljit_s32 reg, sljit_sw init_value)
253 {
254 	FAIL_IF(push_inst(compiler, ADDIS | D(reg) | A(0) | IMM(init_value >> 16)));
255 	return push_inst(compiler, ORI | S(reg) | A(reg) | IMM(init_value));
256 }
257 
sljit_set_jump_addr(sljit_uw addr,sljit_uw new_target,sljit_sw executable_offset)258 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_jump_addr(sljit_uw addr, sljit_uw new_target, sljit_sw executable_offset)
259 {
260 	sljit_ins *inst = (sljit_ins *)addr;
261 
262 	SLJIT_ASSERT((inst[0] & 0xfc1f0000) == ADDIS && (inst[1] & 0xfc000000) == ORI);
263 	inst[0] = (inst[0] & 0xffff0000) | ((new_target >> 16) & 0xffff);
264 	inst[1] = (inst[1] & 0xffff0000) | (new_target & 0xffff);
265 	inst = (sljit_ins *)SLJIT_ADD_EXEC_OFFSET(inst, executable_offset);
266 	SLJIT_CACHE_FLUSH(inst, inst + 2);
267 }
268 
sljit_set_const(sljit_uw addr,sljit_sw new_constant,sljit_sw executable_offset)269 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_const(sljit_uw addr, sljit_sw new_constant, sljit_sw executable_offset)
270 {
271 	sljit_ins *inst = (sljit_ins *)addr;
272 
273 	SLJIT_ASSERT((inst[0] & 0xfc1f0000) == ADDIS && (inst[1] & 0xfc000000) == ORI);
274 	inst[0] = (inst[0] & 0xffff0000) | ((new_constant >> 16) & 0xffff);
275 	inst[1] = (inst[1] & 0xffff0000) | (new_constant & 0xffff);
276 	inst = (sljit_ins *)SLJIT_ADD_EXEC_OFFSET(inst, executable_offset);
277 	SLJIT_CACHE_FLUSH(inst, inst + 2);
278 }
279