1 // Copyright 2011 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef V8_X87_CODE_STUBS_X87_H_
6 #define V8_X87_CODE_STUBS_X87_H_
12 void ArrayNativeCode(MacroAssembler* masm,
14 Label* call_generic_code);
17 class StringHelper : public AllStatic {
19 // Generate code for copying characters using the rep movs instruction.
20 // Copies ecx characters from esi to edi. Copying of overlapping regions is
22 static void GenerateCopyCharacters(MacroAssembler* masm,
27 String::Encoding encoding);
29 // Compares two flat one byte strings and returns result in eax.
30 static void GenerateCompareFlatOneByteStrings(MacroAssembler* masm,
31 Register left, Register right,
36 // Compares two flat one byte strings for equality and returns result in eax.
37 static void GenerateFlatOneByteStringEquals(MacroAssembler* masm,
38 Register left, Register right,
43 static void GenerateOneByteCharsCompareLoop(
44 MacroAssembler* masm, Register left, Register right, Register length,
45 Register scratch, Label* chars_not_equal,
46 Label::Distance chars_not_equal_near = Label::kFar);
48 DISALLOW_IMPLICIT_CONSTRUCTORS(StringHelper);
52 class NameDictionaryLookupStub: public PlatformCodeStub {
54 enum LookupMode { POSITIVE_LOOKUP, NEGATIVE_LOOKUP };
56 NameDictionaryLookupStub(Isolate* isolate, Register dictionary,
57 Register result, Register index, LookupMode mode)
58 : PlatformCodeStub(isolate) {
59 minor_key_ = DictionaryBits::encode(dictionary.code()) |
60 ResultBits::encode(result.code()) |
61 IndexBits::encode(index.code()) | LookupModeBits::encode(mode);
64 static void GenerateNegativeLookup(MacroAssembler* masm,
71 static void GeneratePositiveLookup(MacroAssembler* masm,
79 bool SometimesSetsUpAFrame() override { return false; }
82 static const int kInlinedProbes = 4;
83 static const int kTotalProbes = 20;
85 static const int kCapacityOffset =
86 NameDictionary::kHeaderSize +
87 NameDictionary::kCapacityIndex * kPointerSize;
89 static const int kElementsStartOffset =
90 NameDictionary::kHeaderSize +
91 NameDictionary::kElementsStartIndex * kPointerSize;
93 Register dictionary() const {
94 return Register::from_code(DictionaryBits::decode(minor_key_));
97 Register result() const {
98 return Register::from_code(ResultBits::decode(minor_key_));
101 Register index() const {
102 return Register::from_code(IndexBits::decode(minor_key_));
105 LookupMode mode() const { return LookupModeBits::decode(minor_key_); }
107 class DictionaryBits: public BitField<int, 0, 3> {};
108 class ResultBits: public BitField<int, 3, 3> {};
109 class IndexBits: public BitField<int, 6, 3> {};
110 class LookupModeBits: public BitField<LookupMode, 9, 1> {};
112 DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
113 DEFINE_PLATFORM_CODE_STUB(NameDictionaryLookup, PlatformCodeStub);
117 class RecordWriteStub: public PlatformCodeStub {
119 RecordWriteStub(Isolate* isolate, Register object, Register value,
120 Register address, RememberedSetAction remembered_set_action,
121 SaveFPRegsMode fp_mode)
122 : PlatformCodeStub(isolate),
123 regs_(object, // An input reg.
124 address, // An input reg.
125 value) { // One scratch reg.
126 minor_key_ = ObjectBits::encode(object.code()) |
127 ValueBits::encode(value.code()) |
128 AddressBits::encode(address.code()) |
129 RememberedSetActionBits::encode(remembered_set_action) |
130 SaveFPRegsModeBits::encode(fp_mode);
133 RecordWriteStub(uint32_t key, Isolate* isolate)
134 : PlatformCodeStub(key, isolate), regs_(object(), address(), value()) {}
139 INCREMENTAL_COMPACTION
142 bool SometimesSetsUpAFrame() override { return false; }
144 static const byte kTwoByteNopInstruction = 0x3c; // Cmpb al, #imm8.
145 static const byte kTwoByteJumpInstruction = 0xeb; // Jmp #imm8.
147 static const byte kFiveByteNopInstruction = 0x3d; // Cmpl eax, #imm32.
148 static const byte kFiveByteJumpInstruction = 0xe9; // Jmp #imm32.
150 static Mode GetMode(Code* stub) {
151 byte first_instruction = stub->instruction_start()[0];
152 byte second_instruction = stub->instruction_start()[2];
154 if (first_instruction == kTwoByteJumpInstruction) {
158 DCHECK(first_instruction == kTwoByteNopInstruction);
160 if (second_instruction == kFiveByteJumpInstruction) {
161 return INCREMENTAL_COMPACTION;
164 DCHECK(second_instruction == kFiveByteNopInstruction);
166 return STORE_BUFFER_ONLY;
169 static void Patch(Code* stub, Mode mode) {
171 case STORE_BUFFER_ONLY:
172 DCHECK(GetMode(stub) == INCREMENTAL ||
173 GetMode(stub) == INCREMENTAL_COMPACTION);
174 stub->instruction_start()[0] = kTwoByteNopInstruction;
175 stub->instruction_start()[2] = kFiveByteNopInstruction;
178 DCHECK(GetMode(stub) == STORE_BUFFER_ONLY);
179 stub->instruction_start()[0] = kTwoByteJumpInstruction;
181 case INCREMENTAL_COMPACTION:
182 DCHECK(GetMode(stub) == STORE_BUFFER_ONLY);
183 stub->instruction_start()[0] = kTwoByteNopInstruction;
184 stub->instruction_start()[2] = kFiveByteJumpInstruction;
187 DCHECK(GetMode(stub) == mode);
188 Assembler::FlushICache(stub->GetIsolate(), stub->instruction_start(), 7);
191 DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
194 // This is a helper class for freeing up 3 scratch registers, where the third
195 // is always ecx (needed for shift operations). The input is two registers
196 // that must be preserved and one scratch register provided by the caller.
197 class RegisterAllocation {
199 RegisterAllocation(Register object,
202 : object_orig_(object),
203 address_orig_(address),
204 scratch0_orig_(scratch0),
207 scratch0_(scratch0) {
208 DCHECK(!AreAliased(scratch0, object, address, no_reg));
209 scratch1_ = GetRegThatIsNotEcxOr(object_, address_, scratch0_);
210 if (scratch0.is(ecx)) {
211 scratch0_ = GetRegThatIsNotEcxOr(object_, address_, scratch1_);
213 if (object.is(ecx)) {
214 object_ = GetRegThatIsNotEcxOr(address_, scratch0_, scratch1_);
216 if (address.is(ecx)) {
217 address_ = GetRegThatIsNotEcxOr(object_, scratch0_, scratch1_);
219 DCHECK(!AreAliased(scratch0_, object_, address_, ecx));
222 void Save(MacroAssembler* masm) {
223 DCHECK(!address_orig_.is(object_));
224 DCHECK(object_.is(object_orig_) || address_.is(address_orig_));
225 DCHECK(!AreAliased(object_, address_, scratch1_, scratch0_));
226 DCHECK(!AreAliased(object_orig_, address_, scratch1_, scratch0_));
227 DCHECK(!AreAliased(object_, address_orig_, scratch1_, scratch0_));
228 // We don't have to save scratch0_orig_ because it was given to us as
229 // a scratch register. But if we had to switch to a different reg then
230 // we should save the new scratch0_.
231 if (!scratch0_.is(scratch0_orig_)) masm->push(scratch0_);
232 if (!ecx.is(scratch0_orig_) &&
233 !ecx.is(object_orig_) &&
234 !ecx.is(address_orig_)) {
237 masm->push(scratch1_);
238 if (!address_.is(address_orig_)) {
239 masm->push(address_);
240 masm->mov(address_, address_orig_);
242 if (!object_.is(object_orig_)) {
244 masm->mov(object_, object_orig_);
248 void Restore(MacroAssembler* masm) {
249 // These will have been preserved the entire time, so we just need to move
250 // them back. Only in one case is the orig_ reg different from the plain
251 // one, since only one of them can alias with ecx.
252 if (!object_.is(object_orig_)) {
253 masm->mov(object_orig_, object_);
256 if (!address_.is(address_orig_)) {
257 masm->mov(address_orig_, address_);
260 masm->pop(scratch1_);
261 if (!ecx.is(scratch0_orig_) &&
262 !ecx.is(object_orig_) &&
263 !ecx.is(address_orig_)) {
266 if (!scratch0_.is(scratch0_orig_)) masm->pop(scratch0_);
269 // If we have to call into C then we need to save and restore all caller-
270 // saved registers that were not already preserved. The caller saved
271 // registers are eax, ecx and edx. The three scratch registers (incl. ecx)
272 // will be restored by other means so we don't bother pushing them here.
273 void SaveCallerSaveRegisters(MacroAssembler* masm, SaveFPRegsMode mode) {
274 if (!scratch0_.is(eax) && !scratch1_.is(eax)) masm->push(eax);
275 if (!scratch0_.is(edx) && !scratch1_.is(edx)) masm->push(edx);
276 if (mode == kSaveFPRegs) {
277 // Save FPU state in m108byte.
278 masm->sub(esp, Immediate(108));
279 masm->fnsave(Operand(esp, 0));
283 inline void RestoreCallerSaveRegisters(MacroAssembler* masm,
284 SaveFPRegsMode mode) {
285 if (mode == kSaveFPRegs) {
286 // Restore FPU state in m108byte.
287 masm->frstor(Operand(esp, 0));
288 masm->add(esp, Immediate(108));
290 if (!scratch0_.is(edx) && !scratch1_.is(edx)) masm->pop(edx);
291 if (!scratch0_.is(eax) && !scratch1_.is(eax)) masm->pop(eax);
294 inline Register object() { return object_; }
295 inline Register address() { return address_; }
296 inline Register scratch0() { return scratch0_; }
297 inline Register scratch1() { return scratch1_; }
300 Register object_orig_;
301 Register address_orig_;
302 Register scratch0_orig_;
307 // Third scratch register is always ecx.
309 Register GetRegThatIsNotEcxOr(Register r1,
312 for (int i = 0; i < Register::NumAllocatableRegisters(); i++) {
313 Register candidate = Register::FromAllocationIndex(i);
314 if (candidate.is(ecx)) continue;
315 if (candidate.is(r1)) continue;
316 if (candidate.is(r2)) continue;
317 if (candidate.is(r3)) continue;
323 friend class RecordWriteStub;
326 enum OnNoNeedToInformIncrementalMarker {
327 kReturnOnNoNeedToInformIncrementalMarker,
328 kUpdateRememberedSetOnNoNeedToInformIncrementalMarker
331 inline Major MajorKey() const final { return RecordWrite; }
333 void Generate(MacroAssembler* masm) override;
334 void GenerateIncremental(MacroAssembler* masm, Mode mode);
335 void CheckNeedsToInformIncrementalMarker(
336 MacroAssembler* masm,
337 OnNoNeedToInformIncrementalMarker on_no_need,
339 void InformIncrementalMarker(MacroAssembler* masm);
341 void Activate(Code* code) override {
342 code->GetHeap()->incremental_marking()->ActivateGeneratedStub(code);
345 Register object() const {
346 return Register::from_code(ObjectBits::decode(minor_key_));
349 Register value() const {
350 return Register::from_code(ValueBits::decode(minor_key_));
353 Register address() const {
354 return Register::from_code(AddressBits::decode(minor_key_));
357 RememberedSetAction remembered_set_action() const {
358 return RememberedSetActionBits::decode(minor_key_);
361 SaveFPRegsMode save_fp_regs_mode() const {
362 return SaveFPRegsModeBits::decode(minor_key_);
365 class ObjectBits: public BitField<int, 0, 3> {};
366 class ValueBits: public BitField<int, 3, 3> {};
367 class AddressBits: public BitField<int, 6, 3> {};
368 class RememberedSetActionBits: public BitField<RememberedSetAction, 9, 1> {};
369 class SaveFPRegsModeBits : public BitField<SaveFPRegsMode, 10, 1> {};
371 RegisterAllocation regs_;
373 DISALLOW_COPY_AND_ASSIGN(RecordWriteStub);
377 } // namespace internal
380 #endif // V8_X87_CODE_STUBS_X87_H_