2 // Copyright 2011 the V8 project authors. All rights reserved.
3 // Redistribution and use in source and binary forms, with or without
4 // modification, are permitted provided that the following conditions are
7 // * Redistributions of source code must retain the above copyright
8 // notice, this list of conditions and the following disclaimer.
9 // * Redistributions in binary form must reproduce the above
10 // copyright notice, this list of conditions and the following
11 // disclaimer in the documentation and/or other materials provided
12 // with the distribution.
13 // * Neither the name of Google Inc. nor the names of its
14 // contributors may be used to endorse or promote products derived
15 // from this software without specific prior written permission.
17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 #include "deoptimizer.h"
33 #include "full-codegen.h"
34 #include "safepoint-table.h"
40 int Deoptimizer::patch_size() {
41 const int kCallInstructionSizeInWords = 4;
42 return kCallInstructionSizeInWords * Assembler::kInstrSize;
46 void Deoptimizer::PatchCodeForDeoptimization(Isolate* isolate, Code* code) {
47 Address code_start_address = code->instruction_start();
48 // Invalidate the relocation information, as it will become invalid by the
49 // code patching below, and is not needed any more.
50 code->InvalidateRelocation();
52 // For each LLazyBailout instruction insert a call to the corresponding
53 // deoptimization entry.
54 DeoptimizationInputData* deopt_data =
55 DeoptimizationInputData::cast(code->deoptimization_data());
57 Address prev_call_address = NULL;
59 for (int i = 0; i < deopt_data->DeoptCount(); i++) {
60 if (deopt_data->Pc(i)->value() == -1) continue;
61 Address call_address = code_start_address + deopt_data->Pc(i)->value();
62 Address deopt_entry = GetDeoptimizationEntry(isolate, i, LAZY);
63 int call_size_in_bytes = MacroAssembler::CallSize(deopt_entry,
65 int call_size_in_words = call_size_in_bytes / Assembler::kInstrSize;
66 ASSERT(call_size_in_bytes % Assembler::kInstrSize == 0);
67 ASSERT(call_size_in_bytes <= patch_size());
68 CodePatcher patcher(call_address, call_size_in_words);
69 patcher.masm()->Call(deopt_entry, RelocInfo::NONE32);
70 ASSERT(prev_call_address == NULL ||
71 call_address >= prev_call_address + patch_size());
72 ASSERT(call_address + patch_size() <= code->instruction_end());
75 prev_call_address = call_address;
81 void Deoptimizer::FillInputFrame(Address tos, JavaScriptFrame* frame) {
82 // Set the register values. The values are not important as there are no
83 // callee saved registers in JavaScript frames, so all registers are
84 // spilled. Registers fp and sp are set to the correct values though.
86 for (int i = 0; i < Register::kNumRegisters; i++) {
87 input_->SetRegister(i, i * 4);
89 input_->SetRegister(sp.code(), reinterpret_cast<intptr_t>(frame->sp()));
90 input_->SetRegister(fp.code(), reinterpret_cast<intptr_t>(frame->fp()));
91 for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); i++) {
92 input_->SetDoubleRegister(i, 0.0);
95 // Fill the frame content from the actual data on the frame.
96 for (unsigned i = 0; i < input_->GetFrameSize(); i += kPointerSize) {
97 input_->SetFrameSlot(i, Memory::uint32_at(tos + i));
102 void Deoptimizer::SetPlatformCompiledStubRegisters(
103 FrameDescription* output_frame, CodeStubInterfaceDescriptor* descriptor) {
104 ApiFunction function(descriptor->deoptimization_handler_);
105 ExternalReference xref(&function, ExternalReference::BUILTIN_CALL, isolate_);
106 intptr_t handler = reinterpret_cast<intptr_t>(xref.address());
107 int params = descriptor->GetHandlerParameterCount();
108 output_frame->SetRegister(s0.code(), params);
109 output_frame->SetRegister(s1.code(), (params - 1) * kPointerSize);
110 output_frame->SetRegister(s2.code(), handler);
114 void Deoptimizer::CopyDoubleRegisters(FrameDescription* output_frame) {
115 for (int i = 0; i < DoubleRegister::kMaxNumRegisters; ++i) {
116 double double_value = input_->GetDoubleRegister(i);
117 output_frame->SetDoubleRegister(i, double_value);
122 bool Deoptimizer::HasAlignmentPadding(JSFunction* function) {
123 // There is no dynamic alignment padding on MIPS in the input frame.
128 Code* Deoptimizer::NotifyStubFailureBuiltin() {
129 return isolate_->builtins()->builtin(Builtins::kNotifyStubFailureSaveDoubles);
136 // This code tries to be close to ia32 code so that any changes can be
138 void Deoptimizer::EntryGenerator::Generate() {
141 // Unlike on ARM we don't save all the registers, just the useful ones.
142 // For the rest, there are gaps on the stack, so the offsets remain the same.
143 const int kNumberOfRegisters = Register::kNumRegisters;
145 RegList restored_regs = kJSCallerSaved | kCalleeSaved;
146 RegList saved_regs = restored_regs | sp.bit() | ra.bit();
148 const int kDoubleRegsSize =
149 kDoubleSize * FPURegister::kMaxNumAllocatableRegisters;
151 // Save all FPU registers before messing with them.
152 __ Subu(sp, sp, Operand(kDoubleRegsSize));
153 for (int i = 0; i < FPURegister::kMaxNumAllocatableRegisters; ++i) {
154 FPURegister fpu_reg = FPURegister::FromAllocationIndex(i);
155 int offset = i * kDoubleSize;
156 __ sdc1(fpu_reg, MemOperand(sp, offset));
159 // Push saved_regs (needed to populate FrameDescription::registers_).
160 // Leave gaps for other registers.
161 __ Subu(sp, sp, kNumberOfRegisters * kPointerSize);
162 for (int16_t i = kNumberOfRegisters - 1; i >= 0; i--) {
163 if ((saved_regs & (1 << i)) != 0) {
164 __ sw(ToRegister(i), MemOperand(sp, kPointerSize * i));
168 const int kSavedRegistersAreaSize =
169 (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize;
171 // Get the bailout id from the stack.
172 __ lw(a2, MemOperand(sp, kSavedRegistersAreaSize));
174 // Get the address of the location in the code object (a3) (return
175 // address for lazy deoptimization) and compute the fp-to-sp delta in
178 // Correct one word for bailout id.
179 __ Addu(t0, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
183 // Allocate a new deoptimizer object.
184 // Pass four arguments in a0 to a3 and fifth & sixth arguments on stack.
185 __ PrepareCallCFunction(6, t1);
186 __ lw(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
187 __ li(a1, Operand(type())); // bailout type,
188 // a2: bailout id already loaded.
189 // a3: code address or 0 already loaded.
190 __ sw(t0, CFunctionArgumentOperand(5)); // Fp-to-sp delta.
191 __ li(t1, Operand(ExternalReference::isolate_address(isolate())));
192 __ sw(t1, CFunctionArgumentOperand(6)); // Isolate.
193 // Call Deoptimizer::New().
195 AllowExternalCallThatCantCauseGC scope(masm());
196 __ CallCFunction(ExternalReference::new_deoptimizer_function(isolate()), 6);
199 // Preserve "deoptimizer" object in register v0 and get the input
200 // frame descriptor pointer to a1 (deoptimizer->input_);
201 // Move deopt-obj to a0 for call to Deoptimizer::ComputeOutputFrames() below.
203 __ lw(a1, MemOperand(v0, Deoptimizer::input_offset()));
205 // Copy core registers into FrameDescription::registers_[kNumRegisters].
206 ASSERT(Register::kNumRegisters == kNumberOfRegisters);
207 for (int i = 0; i < kNumberOfRegisters; i++) {
208 int offset = (i * kPointerSize) + FrameDescription::registers_offset();
209 if ((saved_regs & (1 << i)) != 0) {
210 __ lw(a2, MemOperand(sp, i * kPointerSize));
211 __ sw(a2, MemOperand(a1, offset));
212 } else if (FLAG_debug_code) {
213 __ li(a2, kDebugZapValue);
214 __ sw(a2, MemOperand(a1, offset));
218 int double_regs_offset = FrameDescription::double_registers_offset();
219 // Copy FPU registers to
220 // double_registers_[DoubleRegister::kNumAllocatableRegisters]
221 for (int i = 0; i < FPURegister::NumAllocatableRegisters(); ++i) {
222 int dst_offset = i * kDoubleSize + double_regs_offset;
223 int src_offset = i * kDoubleSize + kNumberOfRegisters * kPointerSize;
224 __ ldc1(f0, MemOperand(sp, src_offset));
225 __ sdc1(f0, MemOperand(a1, dst_offset));
228 // Remove the bailout id and the saved registers from the stack.
229 __ Addu(sp, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
231 // Compute a pointer to the unwinding limit in register a2; that is
232 // the first stack slot not part of the input frame.
233 __ lw(a2, MemOperand(a1, FrameDescription::frame_size_offset()));
236 // Unwind the stack down to - but not including - the unwinding
237 // limit and copy the contents of the activation frame to the input
238 // frame description.
239 __ Addu(a3, a1, Operand(FrameDescription::frame_content_offset()));
241 Label pop_loop_header;
242 __ BranchShort(&pop_loop_header);
245 __ sw(t0, MemOperand(a3, 0));
246 __ addiu(a3, a3, sizeof(uint32_t));
247 __ bind(&pop_loop_header);
248 __ BranchShort(&pop_loop, ne, a2, Operand(sp));
250 // Compute the output frame in the deoptimizer.
251 __ push(a0); // Preserve deoptimizer object across call.
252 // a0: deoptimizer object; a1: scratch.
253 __ PrepareCallCFunction(1, a1);
254 // Call Deoptimizer::ComputeOutputFrames().
256 AllowExternalCallThatCantCauseGC scope(masm());
258 ExternalReference::compute_output_frames_function(isolate()), 1);
260 __ pop(a0); // Restore deoptimizer object (class Deoptimizer).
262 // Replace the current (input) frame with the output frames.
263 Label outer_push_loop, inner_push_loop,
264 outer_loop_header, inner_loop_header;
265 // Outer loop state: t0 = current "FrameDescription** output_",
266 // a1 = one past the last FrameDescription**.
267 __ lw(a1, MemOperand(a0, Deoptimizer::output_count_offset()));
268 __ lw(t0, MemOperand(a0, Deoptimizer::output_offset())); // t0 is output_.
269 __ sll(a1, a1, kPointerSizeLog2); // Count to offset.
270 __ addu(a1, t0, a1); // a1 = one past the last FrameDescription**.
271 __ jmp(&outer_loop_header);
272 __ bind(&outer_push_loop);
273 // Inner loop state: a2 = current FrameDescription*, a3 = loop index.
274 __ lw(a2, MemOperand(t0, 0)); // output_[ix]
275 __ lw(a3, MemOperand(a2, FrameDescription::frame_size_offset()));
276 __ jmp(&inner_loop_header);
277 __ bind(&inner_push_loop);
278 __ Subu(a3, a3, Operand(sizeof(uint32_t)));
279 __ Addu(t2, a2, Operand(a3));
280 __ lw(t3, MemOperand(t2, FrameDescription::frame_content_offset()));
282 __ bind(&inner_loop_header);
283 __ BranchShort(&inner_push_loop, ne, a3, Operand(zero_reg));
285 __ Addu(t0, t0, Operand(kPointerSize));
286 __ bind(&outer_loop_header);
287 __ BranchShort(&outer_push_loop, lt, t0, Operand(a1));
289 __ lw(a1, MemOperand(a0, Deoptimizer::input_offset()));
290 for (int i = 0; i < FPURegister::kMaxNumAllocatableRegisters; ++i) {
291 const FPURegister fpu_reg = FPURegister::FromAllocationIndex(i);
292 int src_offset = i * kDoubleSize + double_regs_offset;
293 __ ldc1(fpu_reg, MemOperand(a1, src_offset));
296 // Push state, pc, and continuation from the last output frame.
297 __ lw(t2, MemOperand(a2, FrameDescription::state_offset()));
300 __ lw(t2, MemOperand(a2, FrameDescription::pc_offset()));
302 __ lw(t2, MemOperand(a2, FrameDescription::continuation_offset()));
306 // Technically restoring 'at' should work unless zero_reg is also restored
307 // but it's safer to check for this.
308 ASSERT(!(at.bit() & restored_regs));
309 // Restore the registers from the last output frame.
311 for (int i = kNumberOfRegisters - 1; i >= 0; i--) {
312 int offset = (i * kPointerSize) + FrameDescription::registers_offset();
313 if ((restored_regs & (1 << i)) != 0) {
314 __ lw(ToRegister(i), MemOperand(at, offset));
318 __ InitializeRootRegister();
320 __ pop(at); // Get continuation, leave pc on stack.
323 __ stop("Unreachable.");
327 // Maximum size of a table entry generated below.
328 const int Deoptimizer::table_entry_size_ = 7 * Assembler::kInstrSize;
330 void Deoptimizer::TableEntryGenerator::GeneratePrologue() {
331 Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm());
333 // Create a sequence of deoptimization entries.
334 // Note that registers are still live when jumping to an entry.
336 __ bind(&table_start);
337 for (int i = 0; i < count(); i++) {
340 __ addiu(sp, sp, -1 * kPointerSize);
341 // Jump over the remaining deopt entries (including this one).
342 // This code is always reached by calling Jump, which puts the target (label
344 const int remaining_entries = (count() - i) * table_entry_size_;
345 __ Addu(t9, t9, remaining_entries);
346 // 'at' was clobbered so we can only load the current entry value here.
348 __ jr(t9); // Expose delay slot.
349 __ sw(at, MemOperand(sp, 0 * kPointerSize)); // In the delay slot.
351 // Pad the rest of the code.
352 while (table_entry_size_ > (masm()->SizeOfCodeGeneratedSince(&start))) {
356 ASSERT_EQ(table_entry_size_, masm()->SizeOfCodeGeneratedSince(&start));
359 ASSERT_EQ(masm()->SizeOfCodeGeneratedSince(&table_start),
360 count() * table_entry_size_);
364 void FrameDescription::SetCallerPc(unsigned offset, intptr_t value) {
365 SetFrameSlot(offset, value);
369 void FrameDescription::SetCallerFp(unsigned offset, intptr_t value) {
370 SetFrameSlot(offset, value);
377 } } // namespace v8::internal