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 		SLJIT_ASSERT(!(flags & ALT_FORM4));
123 		if (!(flags & ALT_SET_FLAGS))
124 			return push_inst(compiler, ADD | D(dst) | A(src1) | B(src2));
125 		if (flags & ALT_FORM5)
126 			return push_inst(compiler, ADDC | RC(ALT_SET_FLAGS) | D(dst) | A(src1) | B(src2));
127 		return push_inst(compiler, ADD | RC(flags) | D(dst) | A(src1) | B(src2));
128 
129 	case SLJIT_ADDC:
130 		return push_inst(compiler, ADDE | D(dst) | A(src1) | B(src2));
131 
132 	case SLJIT_SUB:
133 		if (flags & ALT_FORM1) {
134 			if (flags & ALT_FORM2) {
135 				FAIL_IF(push_inst(compiler, CMPLI | CRD(0) | A(src1) | compiler->imm));
136 				if (!(flags & ALT_FORM3))
137 					return SLJIT_SUCCESS;
138 				return push_inst(compiler, ADDI | D(dst) | A(src1) | (-compiler->imm & 0xffff));
139 			}
140 			FAIL_IF(push_inst(compiler, CMPL | CRD(0) | A(src1) | B(src2)));
141 			if (!(flags & ALT_FORM3))
142 				return SLJIT_SUCCESS;
143 			return push_inst(compiler, SUBF | D(dst) | A(src2) | B(src1));
144 		}
145 
146 		if (flags & ALT_FORM2) {
147 			if (flags & ALT_FORM3) {
148 				FAIL_IF(push_inst(compiler, CMPI | CRD(0) | A(src1) | compiler->imm));
149 				if (!(flags & ALT_FORM4))
150 					return SLJIT_SUCCESS;
151 				return push_inst(compiler, ADDI | D(dst) | A(src1) | (-compiler->imm & 0xffff));
152 			}
153 			FAIL_IF(push_inst(compiler, CMP | CRD(0) | A(src1) | B(src2)));
154 			if (!(flags & ALT_FORM4))
155 				return SLJIT_SUCCESS;
156 			return push_inst(compiler, SUBF | D(dst) | A(src2) | B(src1));
157 		}
158 
159 		if (flags & ALT_FORM3) {
160 			/* Setting XER SO is not enough, CR SO is also needed. */
161 			return push_inst(compiler, SUBF | OE(ALT_SET_FLAGS) | RC(ALT_SET_FLAGS) | D(dst) | A(src2) | B(src1));
162 		}
163 
164 		if (flags & ALT_FORM4) {
165 			/* Flags does not set: BIN_IMM_EXTS unnecessary. */
166 			SLJIT_ASSERT(src2 == TMP_REG2);
167 			return push_inst(compiler, SUBFIC | D(dst) | A(src1) | compiler->imm);
168 		}
169 
170 		if (!(flags & ALT_SET_FLAGS))
171 			return push_inst(compiler, SUBF | D(dst) | A(src2) | B(src1));
172 		if (flags & ALT_FORM5)
173 			return push_inst(compiler, SUBFC | RC(ALT_SET_FLAGS) | D(dst) | A(src2) | B(src1));
174 		return push_inst(compiler, SUBF | RC(flags) | D(dst) | A(src2) | B(src1));
175 
176 	case SLJIT_SUBC:
177 		return push_inst(compiler, SUBFE | D(dst) | A(src2) | B(src1));
178 
179 	case SLJIT_MUL:
180 		if (flags & ALT_FORM1) {
181 			SLJIT_ASSERT(src2 == TMP_REG2);
182 			return push_inst(compiler, MULLI | D(dst) | A(src1) | compiler->imm);
183 		}
184 		return push_inst(compiler, MULLW | OE(flags) | RC(flags) | D(dst) | A(src2) | B(src1));
185 
186 	case SLJIT_AND:
187 		if (flags & ALT_FORM1) {
188 			SLJIT_ASSERT(src2 == TMP_REG2);
189 			return push_inst(compiler, ANDI | S(src1) | A(dst) | compiler->imm);
190 		}
191 		if (flags & ALT_FORM2) {
192 			SLJIT_ASSERT(src2 == TMP_REG2);
193 			return push_inst(compiler, ANDIS | S(src1) | A(dst) | compiler->imm);
194 		}
195 		return push_inst(compiler, AND | RC(flags) | S(src1) | A(dst) | B(src2));
196 
197 	case SLJIT_OR:
198 		if (flags & ALT_FORM1) {
199 			SLJIT_ASSERT(src2 == TMP_REG2);
200 			return push_inst(compiler, ORI | S(src1) | A(dst) | compiler->imm);
201 		}
202 		if (flags & ALT_FORM2) {
203 			SLJIT_ASSERT(src2 == TMP_REG2);
204 			return push_inst(compiler, ORIS | S(src1) | A(dst) | compiler->imm);
205 		}
206 		if (flags & ALT_FORM3) {
207 			SLJIT_ASSERT(src2 == TMP_REG2);
208 			FAIL_IF(push_inst(compiler, ORI | S(src1) | A(dst) | IMM(compiler->imm)));
209 			return push_inst(compiler, ORIS | S(dst) | A(dst) | IMM(compiler->imm >> 16));
210 		}
211 		return push_inst(compiler, OR | RC(flags) | S(src1) | A(dst) | B(src2));
212 
213 	case SLJIT_XOR:
214 		if (flags & ALT_FORM1) {
215 			SLJIT_ASSERT(src2 == TMP_REG2);
216 			return push_inst(compiler, XORI | S(src1) | A(dst) | compiler->imm);
217 		}
218 		if (flags & ALT_FORM2) {
219 			SLJIT_ASSERT(src2 == TMP_REG2);
220 			return push_inst(compiler, XORIS | S(src1) | A(dst) | compiler->imm);
221 		}
222 		if (flags & ALT_FORM3) {
223 			SLJIT_ASSERT(src2 == TMP_REG2);
224 			FAIL_IF(push_inst(compiler, XORI | S(src1) | A(dst) | IMM(compiler->imm)));
225 			return push_inst(compiler, XORIS | S(dst) | A(dst) | IMM(compiler->imm >> 16));
226 		}
227 		return push_inst(compiler, XOR | RC(flags) | S(src1) | A(dst) | B(src2));
228 
229 	case SLJIT_SHL:
230 		if (flags & ALT_FORM1) {
231 			SLJIT_ASSERT(src2 == TMP_REG2);
232 			compiler->imm &= 0x1f;
233 			return push_inst(compiler, RLWINM | RC(flags) | S(src1) | A(dst) | (compiler->imm << 11) | ((31 - compiler->imm) << 1));
234 		}
235 		return push_inst(compiler, SLW | RC(flags) | S(src1) | A(dst) | B(src2));
236 
237 	case SLJIT_LSHR:
238 		if (flags & ALT_FORM1) {
239 			SLJIT_ASSERT(src2 == TMP_REG2);
240 			compiler->imm &= 0x1f;
241 			return push_inst(compiler, RLWINM | RC(flags) | S(src1) | A(dst) | (((32 - compiler->imm) & 0x1f) << 11) | (compiler->imm << 6) | (31 << 1));
242 		}
243 		return push_inst(compiler, SRW | RC(flags) | S(src1) | A(dst) | B(src2));
244 
245 	case SLJIT_ASHR:
246 		if (flags & ALT_FORM1) {
247 			SLJIT_ASSERT(src2 == TMP_REG2);
248 			compiler->imm &= 0x1f;
249 			return push_inst(compiler, SRAWI | RC(flags) | S(src1) | A(dst) | (compiler->imm << 11));
250 		}
251 		return push_inst(compiler, SRAW | RC(flags) | S(src1) | A(dst) | B(src2));
252 	}
253 
254 	SLJIT_UNREACHABLE();
255 	return SLJIT_SUCCESS;
256 }
257 
emit_const(struct sljit_compiler * compiler,sljit_s32 reg,sljit_sw init_value)258 static SLJIT_INLINE sljit_s32 emit_const(struct sljit_compiler *compiler, sljit_s32 reg, sljit_sw init_value)
259 {
260 	FAIL_IF(push_inst(compiler, ADDIS | D(reg) | A(0) | IMM(init_value >> 16)));
261 	return push_inst(compiler, ORI | S(reg) | A(reg) | IMM(init_value));
262 }
263 
sljit_set_jump_addr(sljit_uw addr,sljit_uw new_target,sljit_sw executable_offset)264 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_jump_addr(sljit_uw addr, sljit_uw new_target, sljit_sw executable_offset)
265 {
266 	sljit_ins *inst = (sljit_ins *)addr;
267 	SLJIT_UNUSED_ARG(executable_offset);
268 
269 	SLJIT_UPDATE_WX_FLAGS(inst, inst + 2, 0);
270 	SLJIT_ASSERT((inst[0] & 0xfc1f0000) == ADDIS && (inst[1] & 0xfc000000) == ORI);
271 	inst[0] = (inst[0] & 0xffff0000) | ((new_target >> 16) & 0xffff);
272 	inst[1] = (inst[1] & 0xffff0000) | (new_target & 0xffff);
273 	SLJIT_UPDATE_WX_FLAGS(inst, inst + 2, 1);
274 	inst = (sljit_ins *)SLJIT_ADD_EXEC_OFFSET(inst, executable_offset);
275 	SLJIT_CACHE_FLUSH(inst, inst + 2);
276 }
277 
sljit_set_const(sljit_uw addr,sljit_sw new_constant,sljit_sw executable_offset)278 SLJIT_API_FUNC_ATTRIBUTE void sljit_set_const(sljit_uw addr, sljit_sw new_constant, sljit_sw executable_offset)
279 {
280 	sljit_set_jump_addr(addr, new_constant, executable_offset);
281 }
282