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
27static sljit_s32 load_immediate(struct sljit_compiler *compiler, sljit_s32 dst_r, sljit_sw imm, sljit_s32 tmp_r)
28{
29	sljit_sw high;
30
31	SLJIT_ASSERT(dst_r != tmp_r);
32
33	if (imm <= SIMM_MAX && imm >= SIMM_MIN)
34		return push_inst(compiler, ADDI | RD(dst_r) | RS1(TMP_ZERO) | IMM_I(imm));
35
36	if (imm <= 0x7fffffffl && imm >= S32_MIN) {
37		if (imm > S32_MAX) {
38			SLJIT_ASSERT((imm & 0x800) != 0);
39			FAIL_IF(push_inst(compiler, LUI | RD(dst_r) | (sljit_ins)0x80000000u));
40			return push_inst(compiler, XORI | RD(dst_r) | RS1(dst_r) | IMM_I(imm));
41		}
42
43		if ((imm & 0x800) != 0)
44			imm += 0x1000;
45
46		FAIL_IF(push_inst(compiler, LUI | RD(dst_r) | (sljit_ins)(imm & ~0xfff)));
47
48		if ((imm & 0xfff) == 0)
49			return SLJIT_SUCCESS;
50
51		return push_inst(compiler, ADDI | RD(dst_r) | RS1(dst_r) | IMM_I(imm));
52	}
53
54	/* Trailing zeroes could be used to produce shifted immediates. */
55
56	if (imm <= 0x7ffffffffffl && imm >= -0x80000000000l) {
57		high = imm >> 12;
58
59		if (imm & 0x800)
60			high = ~high;
61
62		if (high > S32_MAX) {
63			SLJIT_ASSERT((high & 0x800) != 0);
64			FAIL_IF(push_inst(compiler, LUI | RD(dst_r) | (sljit_ins)0x80000000u));
65			FAIL_IF(push_inst(compiler, XORI | RD(dst_r) | RS1(dst_r) | IMM_I(high)));
66		} else {
67			if ((high & 0x800) != 0)
68				high += 0x1000;
69
70			FAIL_IF(push_inst(compiler, LUI | RD(dst_r) | (sljit_ins)(high & ~0xfff)));
71
72			if ((high & 0xfff) != 0)
73				FAIL_IF(push_inst(compiler, ADDI | RD(dst_r) | RS1(dst_r) | IMM_I(high)));
74		}
75
76		FAIL_IF(push_inst(compiler, SLLI | RD(dst_r) | RS1(dst_r) | IMM_I(12)));
77
78		if ((imm & 0xfff) != 0)
79			return push_inst(compiler, XORI | RD(dst_r) | RS1(dst_r) | IMM_I(imm));
80
81		return SLJIT_SUCCESS;
82	}
83
84	high = imm >> 32;
85	imm = (sljit_s32)imm;
86
87	if ((imm & 0x80000000l) != 0)
88		high = ~high;
89
90	if (high <= 0x7ffff && high >= -0x80000) {
91		FAIL_IF(push_inst(compiler, LUI | RD(tmp_r) | (sljit_ins)(high << 12)));
92		high = 0x1000;
93	} else {
94		if ((high & 0x800) != 0)
95			high += 0x1000;
96
97		FAIL_IF(push_inst(compiler, LUI | RD(tmp_r) | (sljit_ins)(high & ~0xfff)));
98		high &= 0xfff;
99	}
100
101	if (imm <= SIMM_MAX && imm >= SIMM_MIN) {
102		FAIL_IF(push_inst(compiler, ADDI | RD(dst_r) | RS1(TMP_ZERO) | IMM_I(imm)));
103		imm = 0;
104	} else if (imm > S32_MAX) {
105		SLJIT_ASSERT((imm & 0x800) != 0);
106
107		FAIL_IF(push_inst(compiler, LUI | RD(dst_r) | (sljit_ins)0x80000000u));
108		imm = 0x1000 | (imm & 0xfff);
109	} else {
110		if ((imm & 0x800) != 0)
111			imm += 0x1000;
112
113		FAIL_IF(push_inst(compiler, LUI | RD(dst_r) | (sljit_ins)(imm & ~0xfff)));
114		imm &= 0xfff;
115	}
116
117	if ((high & 0xfff) != 0)
118		FAIL_IF(push_inst(compiler, ADDI | RD(tmp_r) | RS1(tmp_r) | IMM_I(high)));
119
120	if (imm & 0x1000)
121		FAIL_IF(push_inst(compiler, XORI | RD(dst_r) | RS1(dst_r) | IMM_I(imm)));
122	else if (imm != 0)
123		FAIL_IF(push_inst(compiler, ADDI | RD(dst_r) | RS1(dst_r) | IMM_I(imm)));
124
125	FAIL_IF(push_inst(compiler, SLLI | RD(tmp_r) | RS1(tmp_r) | IMM_I((high & 0x1000) ? 20 : 32)));
126	return push_inst(compiler, XOR | RD(dst_r) | RS1(dst_r) | RS2(tmp_r));
127}
128
129static SLJIT_INLINE sljit_s32 emit_const(struct sljit_compiler *compiler, sljit_s32 dst, sljit_sw init_value, sljit_ins last_ins)
130{
131	sljit_sw high;
132
133	if ((init_value & 0x800) != 0)
134		init_value += 0x1000;
135
136	high = init_value >> 32;
137
138	if ((init_value & 0x80000000l) != 0)
139		high = ~high;
140
141	if ((high & 0x800) != 0)
142		high += 0x1000;
143
144	FAIL_IF(push_inst(compiler, LUI | RD(TMP_REG3) | (sljit_ins)(high & ~0xfff)));
145	FAIL_IF(push_inst(compiler, ADDI | RD(TMP_REG3) | RS1(TMP_REG3) | IMM_I(high)));
146	FAIL_IF(push_inst(compiler, LUI | RD(dst) | (sljit_ins)(init_value & ~0xfff)));
147	FAIL_IF(push_inst(compiler, SLLI | RD(TMP_REG3) | RS1(TMP_REG3) | IMM_I(32)));
148	FAIL_IF(push_inst(compiler, XOR | RD(dst) | RS1(dst) | RS2(TMP_REG3)));
149	return push_inst(compiler, last_ins | RS1(dst) | IMM_I(init_value));
150}
151
152SLJIT_API_FUNC_ATTRIBUTE void sljit_set_jump_addr(sljit_uw addr, sljit_uw new_target, sljit_sw executable_offset)
153{
154	sljit_ins *inst = (sljit_ins*)addr;
155	sljit_sw high;
156	SLJIT_UNUSED_ARG(executable_offset);
157
158	if ((new_target & 0x800) != 0)
159		new_target += 0x1000;
160
161	high = (sljit_sw)new_target >> 32;
162
163	if ((new_target & 0x80000000l) != 0)
164		high = ~high;
165
166	if ((high & 0x800) != 0)
167		high += 0x1000;
168
169	SLJIT_UPDATE_WX_FLAGS(inst, inst + 5, 0);
170
171	SLJIT_ASSERT((inst[0] & 0x7f) == LUI);
172	inst[0] = (inst[0] & 0xfff) | (sljit_ins)(high & ~0xfff);
173	SLJIT_ASSERT((inst[1] & 0x707f) == ADDI);
174	inst[1] = (inst[1] & 0xfffff) | IMM_I(high);
175	SLJIT_ASSERT((inst[2] & 0x7f) == LUI);
176	inst[2] = (inst[2] & 0xfff) | (sljit_ins)((sljit_sw)new_target & ~0xfff);
177	SLJIT_ASSERT((inst[5] & 0x707f) == ADDI || (inst[5] & 0x707f) == JALR);
178	inst[5] = (inst[5] & 0xfffff) | IMM_I(new_target);
179	SLJIT_UPDATE_WX_FLAGS(inst, inst + 5, 1);
180
181	inst = (sljit_ins *)SLJIT_ADD_EXEC_OFFSET(inst, executable_offset);
182	SLJIT_CACHE_FLUSH(inst, inst + 5);
183}
184