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Issue 144963003: A64: add missing files. (Closed) Base URL: https://v8.googlecode.com/svn/branches/experimental/a64
Patch Set: Created 6 years, 11 months ago
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1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Redistribution and use in source and binary forms, with or without
3 // modification, are permitted provided that the following conditions are
4 // met:
5 //
6 // * Redistributions of source code must retain the above copyright
7 // notice, this list of conditions and the following disclaimer.
8 // * Redistributions in binary form must reproduce the above
9 // copyright notice, this list of conditions and the following
10 // disclaimer in the documentation and/or other materials provided
11 // with the distribution.
12 // * Neither the name of Google Inc. nor the names of its
13 // contributors may be used to endorse or promote products derived
14 // from this software without specific prior written permission.
15 //
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28 #include "v8.h"
29
30 #if defined(V8_TARGET_ARCH_A64)
31
32 #include "a64/instructions-a64.h"
33 #include "a64/assembler-a64-inl.h"
34
35 namespace v8 {
36 namespace internal {
37
38
39 static uint64_t RotateRight(uint64_t value,
40 unsigned int rotate,
41 unsigned int width) {
42 ASSERT(width <= 64);
43 rotate &= 63;
44 return ((value & ((1UL << rotate) - 1UL)) << (width - rotate)) |
45 (value >> rotate);
46 }
47
48
49 static uint64_t RepeatBitsAcrossReg(unsigned reg_size,
50 uint64_t value,
51 unsigned width) {
52 ASSERT((width == 2) || (width == 4) || (width == 8) || (width == 16) ||
53 (width == 32));
54 ASSERT((reg_size == kWRegSize) || (reg_size == kXRegSize));
55 uint64_t result = value & ((1UL << width) - 1UL);
56 for (unsigned i = width; i < reg_size; i *= 2) {
57 result |= (result << i);
58 }
59 return result;
60 }
61
62
63 // Logical immediates can't encode zero, so a return value of zero is used to
64 // indicate a failure case. Specifically, where the constraints on imm_s are not
65 // met.
66 uint64_t Instruction::ImmLogical() {
67 unsigned reg_size = SixtyFourBits() ? kXRegSize : kWRegSize;
68 int64_t n = BitN();
69 int64_t imm_s = ImmSetBits();
70 int64_t imm_r = ImmRotate();
71
72 // An integer is constructed from the n, imm_s and imm_r bits according to
73 // the following table:
74 //
75 // N imms immr size S R
76 // 1 ssssss rrrrrr 64 UInt(ssssss) UInt(rrrrrr)
77 // 0 0sssss xrrrrr 32 UInt(sssss) UInt(rrrrr)
78 // 0 10ssss xxrrrr 16 UInt(ssss) UInt(rrrr)
79 // 0 110sss xxxrrr 8 UInt(sss) UInt(rrr)
80 // 0 1110ss xxxxrr 4 UInt(ss) UInt(rr)
81 // 0 11110s xxxxxr 2 UInt(s) UInt(r)
82 // (s bits must not be all set)
83 //
84 // A pattern is constructed of size bits, where the least significant S+1
85 // bits are set. The pattern is rotated right by R, and repeated across a
86 // 32 or 64-bit value, depending on destination register width.
87 //
88
89 if (n == 1) {
90 if (imm_s == 0x3F) {
91 return 0;
92 }
93 uint64_t bits = (1UL << (imm_s + 1)) - 1;
94 return RotateRight(bits, imm_r, 64);
95 } else {
96 if ((imm_s >> 1) == 0x1F) {
97 return 0;
98 }
99 for (int width = 0x20; width >= 0x2; width >>= 1) {
100 if ((imm_s & width) == 0) {
101 int mask = width - 1;
102 if ((imm_s & mask) == mask) {
103 return 0;
104 }
105 uint64_t bits = (1UL << ((imm_s & mask) + 1)) - 1;
106 return RepeatBitsAcrossReg(reg_size,
107 RotateRight(bits, imm_r & mask, width),
108 width);
109 }
110 }
111 }
112 UNREACHABLE();
113 return 0;
114 }
115
116
117 float Instruction::ImmFP32() {
118 // ImmFP: abcdefgh (8 bits)
119 // Single: aBbb.bbbc.defg.h000.0000.0000.0000.0000 (32 bits)
120 // where B is b ^ 1
121 uint32_t bits = ImmFP();
122 uint32_t bit7 = (bits >> 7) & 0x1;
123 uint32_t bit6 = (bits >> 6) & 0x1;
124 uint32_t bit5_to_0 = bits & 0x3f;
125 uint32_t result = (bit7 << 31) | ((32 - bit6) << 25) | (bit5_to_0 << 19);
126
127 return rawbits_to_float(result);
128 }
129
130
131 double Instruction::ImmFP64() {
132 // ImmFP: abcdefgh (8 bits)
133 // Double: aBbb.bbbb.bbcd.efgh.0000.0000.0000.0000
134 // 0000.0000.0000.0000.0000.0000.0000.0000 (64 bits)
135 // where B is b ^ 1
136 uint32_t bits = ImmFP();
137 uint64_t bit7 = (bits >> 7) & 0x1;
138 uint64_t bit6 = (bits >> 6) & 0x1;
139 uint64_t bit5_to_0 = bits & 0x3f;
140 uint64_t result = (bit7 << 63) | ((256 - bit6) << 54) | (bit5_to_0 << 48);
141
142 return rawbits_to_double(result);
143 }
144
145
146 LSDataSize CalcLSPairDataSize(LoadStorePairOp op) {
147 switch (op) {
148 case STP_x:
149 case LDP_x:
150 case STP_d:
151 case LDP_d: return LSDoubleWord;
152 default: return LSWord;
153 }
154 }
155
156
157 ptrdiff_t Instruction::ImmPCOffset() {
158 ptrdiff_t offset;
159 if (IsPCRelAddressing()) {
160 // PC-relative addressing. Only ADR is supported.
161 offset = ImmPCRel();
162 } else if (BranchType() != UnknownBranchType) {
163 // All PC-relative branches.
164 // Relative branch offsets are instruction-size-aligned.
165 offset = ImmBranch() << kInstructionSizeLog2;
166 } else {
167 // Load literal (offset from PC).
168 ASSERT(IsLdrLiteral());
169 // The offset is always shifted by 2 bits, even for loads to 64-bits
170 // registers.
171 offset = ImmLLiteral() << kInstructionSizeLog2;
172 }
173 return offset;
174 }
175
176
177 Instruction* Instruction::ImmPCOffsetTarget() {
178 return this + ImmPCOffset();
179 }
180
181
182 inline int Instruction::ImmBranch() const {
183 switch (BranchType()) {
184 case CondBranchType: return ImmCondBranch();
185 case UncondBranchType: return ImmUncondBranch();
186 case CompareBranchType: return ImmCmpBranch();
187 case TestBranchType: return ImmTestBranch();
188 default: UNREACHABLE();
189 }
190 return 0;
191 }
192
193
194 void Instruction::SetImmPCOffsetTarget(Instruction* target) {
195 if (IsPCRelAddressing()) {
196 SetPCRelImmTarget(target);
197 } else if (BranchType() != UnknownBranchType) {
198 SetBranchImmTarget(target);
199 } else {
200 SetImmLLiteral(target);
201 }
202 }
203
204
205 void Instruction::SetPCRelImmTarget(Instruction* target) {
206 // ADRP is not supported, so 'this' must point to an ADR instruction.
207 ASSERT(Mask(PCRelAddressingMask) == ADR);
208
209 Instr imm = Assembler::ImmPCRelAddress(target - this);
210
211 SetInstructionBits(Mask(~ImmPCRel_mask) | imm);
212 }
213
214
215 void Instruction::SetBranchImmTarget(Instruction* target) {
216 ASSERT(((target - this) & 3) == 0);
217 Instr branch_imm = 0;
218 uint32_t imm_mask = 0;
219 int offset = (target - this) >> kInstructionSizeLog2;
220 switch (BranchType()) {
221 case CondBranchType: {
222 branch_imm = Assembler::ImmCondBranch(offset);
223 imm_mask = ImmCondBranch_mask;
224 break;
225 }
226 case UncondBranchType: {
227 branch_imm = Assembler::ImmUncondBranch(offset);
228 imm_mask = ImmUncondBranch_mask;
229 break;
230 }
231 case CompareBranchType: {
232 branch_imm = Assembler::ImmCmpBranch(offset);
233 imm_mask = ImmCmpBranch_mask;
234 break;
235 }
236 case TestBranchType: {
237 branch_imm = Assembler::ImmTestBranch(offset);
238 imm_mask = ImmTestBranch_mask;
239 break;
240 }
241 default: UNREACHABLE();
242 }
243 SetInstructionBits(Mask(~imm_mask) | branch_imm);
244 }
245
246
247 void Instruction::SetImmLLiteral(Instruction* source) {
248 ASSERT(((source - this) & 3) == 0);
249 int offset = (source - this) >> kLiteralEntrySizeLog2;
250 Instr imm = Assembler::ImmLLiteral(offset);
251 Instr mask = ImmLLiteral_mask;
252
253 SetInstructionBits(Mask(~mask) | imm);
254 }
255
256
257 // TODO(jbramley): We can't put this inline in the class because things like
258 // xzr and Register are not defined in that header. Consider adding
259 // instructions-a64-inl.h to work around this.
260 bool InstructionSequence::IsInlineData() const {
261 // Inline data is encoded as a single movz instruction which writes to xzr
262 // (x31).
263 return IsMovz() && SixtyFourBits() && (Rd() == xzr.code());
264 // TODO(all): If we extend ::InlineData() to support bigger data, we need
265 // to update this method too.
266 }
267
268
269 // TODO(jbramley): We can't put this inline in the class because things like
270 // xzr and Register are not defined in that header. Consider adding
271 // instructions-a64-inl.h to work around this.
272 uint64_t InstructionSequence::InlineData() const {
273 ASSERT(IsInlineData());
274 uint64_t payload = ImmMoveWide();
275 // TODO(all): If we extend ::InlineData() to support bigger data, we need
276 // to update this method too.
277 return payload;
278 }
279
280
281 } } // namespace v8::internal
282
283 #endif // V8_TARGET_ARCH_A64
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