| // Copyright 2012 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "src/codegen.h" |
| #include "src/deoptimizer.h" |
| #include "src/full-codegen/full-codegen.h" |
| #include "src/register-configuration.h" |
| #include "src/safepoint-table.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| const int Deoptimizer::table_entry_size_ = 8; |
| |
| |
| int Deoptimizer::patch_size() { |
| const int kCallInstructionSizeInWords = 3; |
| return kCallInstructionSizeInWords * Assembler::kInstrSize; |
| } |
| |
| |
| void Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(Handle<Code> code) { |
| // Empty because there is no need for relocation information for the code |
| // patching in Deoptimizer::PatchCodeForDeoptimization below. |
| } |
| |
| |
| void Deoptimizer::PatchCodeForDeoptimization(Isolate* isolate, Code* code) { |
| Address code_start_address = code->instruction_start(); |
| // Invalidate the relocation information, as it will become invalid by the |
| // code patching below, and is not needed any more. |
| code->InvalidateRelocation(); |
| |
| if (FLAG_zap_code_space) { |
| // Fail hard and early if we enter this code object again. |
| byte* pointer = code->FindCodeAgeSequence(); |
| if (pointer != NULL) { |
| pointer += kNoCodeAgeSequenceLength; |
| } else { |
| pointer = code->instruction_start(); |
| } |
| CodePatcher patcher(isolate, pointer, 1); |
| patcher.masm()->bkpt(0); |
| |
| DeoptimizationInputData* data = |
| DeoptimizationInputData::cast(code->deoptimization_data()); |
| int osr_offset = data->OsrPcOffset()->value(); |
| if (osr_offset > 0) { |
| CodePatcher osr_patcher(isolate, code->instruction_start() + osr_offset, |
| 1); |
| osr_patcher.masm()->bkpt(0); |
| } |
| } |
| |
| DeoptimizationInputData* deopt_data = |
| DeoptimizationInputData::cast(code->deoptimization_data()); |
| #ifdef DEBUG |
| Address prev_call_address = NULL; |
| #endif |
| // For each LLazyBailout instruction insert a call to the corresponding |
| // deoptimization entry. |
| for (int i = 0; i < deopt_data->DeoptCount(); i++) { |
| if (deopt_data->Pc(i)->value() == -1) continue; |
| Address call_address = code_start_address + deopt_data->Pc(i)->value(); |
| Address deopt_entry = GetDeoptimizationEntry(isolate, i, LAZY); |
| // We need calls to have a predictable size in the unoptimized code, but |
| // this is optimized code, so we don't have to have a predictable size. |
| int call_size_in_bytes = |
| MacroAssembler::CallSizeNotPredictableCodeSize(isolate, |
| deopt_entry, |
| RelocInfo::NONE32); |
| int call_size_in_words = call_size_in_bytes / Assembler::kInstrSize; |
| DCHECK(call_size_in_bytes % Assembler::kInstrSize == 0); |
| DCHECK(call_size_in_bytes <= patch_size()); |
| CodePatcher patcher(isolate, call_address, call_size_in_words); |
| patcher.masm()->Call(deopt_entry, RelocInfo::NONE32); |
| DCHECK(prev_call_address == NULL || |
| call_address >= prev_call_address + patch_size()); |
| DCHECK(call_address + patch_size() <= code->instruction_end()); |
| #ifdef DEBUG |
| prev_call_address = call_address; |
| #endif |
| } |
| } |
| |
| |
| void Deoptimizer::SetPlatformCompiledStubRegisters( |
| FrameDescription* output_frame, CodeStubDescriptor* descriptor) { |
| ApiFunction function(descriptor->deoptimization_handler()); |
| ExternalReference xref(&function, ExternalReference::BUILTIN_CALL, isolate_); |
| intptr_t handler = reinterpret_cast<intptr_t>(xref.address()); |
| int params = descriptor->GetHandlerParameterCount(); |
| output_frame->SetRegister(r0.code(), params); |
| output_frame->SetRegister(r1.code(), handler); |
| } |
| |
| |
| void Deoptimizer::CopyDoubleRegisters(FrameDescription* output_frame) { |
| for (int i = 0; i < DwVfpRegister::kMaxNumRegisters; ++i) { |
| double double_value = input_->GetDoubleRegister(i); |
| output_frame->SetDoubleRegister(i, double_value); |
| } |
| } |
| |
| #define __ masm()-> |
| |
| // This code tries to be close to ia32 code so that any changes can be |
| // easily ported. |
| void Deoptimizer::TableEntryGenerator::Generate() { |
| GeneratePrologue(); |
| |
| // Save all general purpose registers before messing with them. |
| const int kNumberOfRegisters = Register::kNumRegisters; |
| |
| // Everything but pc, lr and ip which will be saved but not restored. |
| RegList restored_regs = kJSCallerSaved | kCalleeSaved | ip.bit(); |
| |
| const int kDoubleRegsSize = kDoubleSize * DwVfpRegister::kMaxNumRegisters; |
| |
| // Save all allocatable VFP registers before messing with them. |
| DCHECK(kDoubleRegZero.code() == 14); |
| DCHECK(kScratchDoubleReg.code() == 15); |
| |
| // Check CPU flags for number of registers, setting the Z condition flag. |
| __ CheckFor32DRegs(ip); |
| |
| // Push registers d0-d15, and possibly d16-d31, on the stack. |
| // If d16-d31 are not pushed, decrease the stack pointer instead. |
| __ vstm(db_w, sp, d16, d31, ne); |
| __ sub(sp, sp, Operand(16 * kDoubleSize), LeaveCC, eq); |
| __ vstm(db_w, sp, d0, d15); |
| |
| // Push all 16 registers (needed to populate FrameDescription::registers_). |
| // TODO(1588) Note that using pc with stm is deprecated, so we should perhaps |
| // handle this a bit differently. |
| __ stm(db_w, sp, restored_regs | sp.bit() | lr.bit() | pc.bit()); |
| |
| __ mov(ip, Operand(ExternalReference(Isolate::kCEntryFPAddress, isolate()))); |
| __ str(fp, MemOperand(ip)); |
| |
| const int kSavedRegistersAreaSize = |
| (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize; |
| |
| // Get the bailout id from the stack. |
| __ ldr(r2, MemOperand(sp, kSavedRegistersAreaSize)); |
| |
| // Get the address of the location in the code object (r3) (return |
| // address for lazy deoptimization) and compute the fp-to-sp delta in |
| // register r4. |
| __ mov(r3, lr); |
| // Correct one word for bailout id. |
| __ add(r4, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize))); |
| __ sub(r4, fp, r4); |
| |
| // Allocate a new deoptimizer object. |
| // Pass four arguments in r0 to r3 and fifth argument on stack. |
| __ PrepareCallCFunction(6, r5); |
| __ mov(r0, Operand(0)); |
| Label context_check; |
| __ ldr(r1, MemOperand(fp, CommonFrameConstants::kContextOrFrameTypeOffset)); |
| __ JumpIfSmi(r1, &context_check); |
| __ ldr(r0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset)); |
| __ bind(&context_check); |
| __ mov(r1, Operand(type())); // bailout type, |
| // r2: bailout id already loaded. |
| // r3: code address or 0 already loaded. |
| __ str(r4, MemOperand(sp, 0 * kPointerSize)); // Fp-to-sp delta. |
| __ mov(r5, Operand(ExternalReference::isolate_address(isolate()))); |
| __ str(r5, MemOperand(sp, 1 * kPointerSize)); // Isolate. |
| // Call Deoptimizer::New(). |
| { |
| AllowExternalCallThatCantCauseGC scope(masm()); |
| __ CallCFunction(ExternalReference::new_deoptimizer_function(isolate()), 6); |
| } |
| |
| // Preserve "deoptimizer" object in register r0 and get the input |
| // frame descriptor pointer to r1 (deoptimizer->input_); |
| __ ldr(r1, MemOperand(r0, Deoptimizer::input_offset())); |
| |
| // Copy core registers into FrameDescription::registers_[kNumRegisters]. |
| DCHECK(Register::kNumRegisters == kNumberOfRegisters); |
| for (int i = 0; i < kNumberOfRegisters; i++) { |
| int offset = (i * kPointerSize) + FrameDescription::registers_offset(); |
| __ ldr(r2, MemOperand(sp, i * kPointerSize)); |
| __ str(r2, MemOperand(r1, offset)); |
| } |
| |
| // Copy VFP registers to |
| // double_registers_[DoubleRegister::kMaxNumAllocatableRegisters] |
| int double_regs_offset = FrameDescription::double_registers_offset(); |
| const RegisterConfiguration* config = |
| RegisterConfiguration::ArchDefault(RegisterConfiguration::CRANKSHAFT); |
| for (int i = 0; i < config->num_allocatable_double_registers(); ++i) { |
| int code = config->GetAllocatableDoubleCode(i); |
| int dst_offset = code * kDoubleSize + double_regs_offset; |
| int src_offset = code * kDoubleSize + kNumberOfRegisters * kPointerSize; |
| __ vldr(d0, sp, src_offset); |
| __ vstr(d0, r1, dst_offset); |
| } |
| |
| // Remove the bailout id and the saved registers from the stack. |
| __ add(sp, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize))); |
| |
| // Compute a pointer to the unwinding limit in register r2; that is |
| // the first stack slot not part of the input frame. |
| __ ldr(r2, MemOperand(r1, FrameDescription::frame_size_offset())); |
| __ add(r2, r2, sp); |
| |
| // Unwind the stack down to - but not including - the unwinding |
| // limit and copy the contents of the activation frame to the input |
| // frame description. |
| __ add(r3, r1, Operand(FrameDescription::frame_content_offset())); |
| Label pop_loop; |
| Label pop_loop_header; |
| __ b(&pop_loop_header); |
| __ bind(&pop_loop); |
| __ pop(r4); |
| __ str(r4, MemOperand(r3, 0)); |
| __ add(r3, r3, Operand(sizeof(uint32_t))); |
| __ bind(&pop_loop_header); |
| __ cmp(r2, sp); |
| __ b(ne, &pop_loop); |
| |
| // Compute the output frame in the deoptimizer. |
| __ push(r0); // Preserve deoptimizer object across call. |
| // r0: deoptimizer object; r1: scratch. |
| __ PrepareCallCFunction(1, r1); |
| // Call Deoptimizer::ComputeOutputFrames(). |
| { |
| AllowExternalCallThatCantCauseGC scope(masm()); |
| __ CallCFunction( |
| ExternalReference::compute_output_frames_function(isolate()), 1); |
| } |
| __ pop(r0); // Restore deoptimizer object (class Deoptimizer). |
| |
| __ ldr(sp, MemOperand(r0, Deoptimizer::caller_frame_top_offset())); |
| |
| // Replace the current (input) frame with the output frames. |
| Label outer_push_loop, inner_push_loop, |
| outer_loop_header, inner_loop_header; |
| // Outer loop state: r4 = current "FrameDescription** output_", |
| // r1 = one past the last FrameDescription**. |
| __ ldr(r1, MemOperand(r0, Deoptimizer::output_count_offset())); |
| __ ldr(r4, MemOperand(r0, Deoptimizer::output_offset())); // r4 is output_. |
| __ add(r1, r4, Operand(r1, LSL, 2)); |
| __ jmp(&outer_loop_header); |
| __ bind(&outer_push_loop); |
| // Inner loop state: r2 = current FrameDescription*, r3 = loop index. |
| __ ldr(r2, MemOperand(r4, 0)); // output_[ix] |
| __ ldr(r3, MemOperand(r2, FrameDescription::frame_size_offset())); |
| __ jmp(&inner_loop_header); |
| __ bind(&inner_push_loop); |
| __ sub(r3, r3, Operand(sizeof(uint32_t))); |
| __ add(r6, r2, Operand(r3)); |
| __ ldr(r6, MemOperand(r6, FrameDescription::frame_content_offset())); |
| __ push(r6); |
| __ bind(&inner_loop_header); |
| __ cmp(r3, Operand::Zero()); |
| __ b(ne, &inner_push_loop); // test for gt? |
| __ add(r4, r4, Operand(kPointerSize)); |
| __ bind(&outer_loop_header); |
| __ cmp(r4, r1); |
| __ b(lt, &outer_push_loop); |
| |
| // Check CPU flags for number of registers, setting the Z condition flag. |
| __ CheckFor32DRegs(ip); |
| |
| __ ldr(r1, MemOperand(r0, Deoptimizer::input_offset())); |
| for (int i = 0; i < config->num_allocatable_double_registers(); ++i) { |
| int code = config->GetAllocatableDoubleCode(i); |
| DwVfpRegister reg = DwVfpRegister::from_code(code); |
| int src_offset = code * kDoubleSize + double_regs_offset; |
| __ vldr(reg, r1, src_offset); |
| } |
| |
| // Push state, pc, and continuation from the last output frame. |
| __ ldr(r6, MemOperand(r2, FrameDescription::state_offset())); |
| __ push(r6); |
| __ ldr(r6, MemOperand(r2, FrameDescription::pc_offset())); |
| __ push(r6); |
| __ ldr(r6, MemOperand(r2, FrameDescription::continuation_offset())); |
| __ push(r6); |
| |
| // Push the registers from the last output frame. |
| for (int i = kNumberOfRegisters - 1; i >= 0; i--) { |
| int offset = (i * kPointerSize) + FrameDescription::registers_offset(); |
| __ ldr(r6, MemOperand(r2, offset)); |
| __ push(r6); |
| } |
| |
| // Restore the registers from the stack. |
| __ ldm(ia_w, sp, restored_regs); // all but pc registers. |
| __ pop(ip); // remove sp |
| __ pop(ip); // remove lr |
| |
| __ InitializeRootRegister(); |
| |
| __ pop(ip); // remove pc |
| __ pop(ip); // get continuation, leave pc on stack |
| __ pop(lr); |
| __ Jump(ip); |
| __ stop("Unreachable."); |
| } |
| |
| |
| void Deoptimizer::TableEntryGenerator::GeneratePrologue() { |
| // Create a sequence of deoptimization entries. |
| // Note that registers are still live when jumping to an entry. |
| Label done; |
| for (int i = 0; i < count(); i++) { |
| int start = masm()->pc_offset(); |
| USE(start); |
| __ mov(ip, Operand(i)); |
| __ b(&done); |
| DCHECK(masm()->pc_offset() - start == table_entry_size_); |
| } |
| __ bind(&done); |
| __ push(ip); |
| } |
| |
| |
| void FrameDescription::SetCallerPc(unsigned offset, intptr_t value) { |
| SetFrameSlot(offset, value); |
| } |
| |
| |
| void FrameDescription::SetCallerFp(unsigned offset, intptr_t value) { |
| SetFrameSlot(offset, value); |
| } |
| |
| |
| void FrameDescription::SetCallerConstantPool(unsigned offset, intptr_t value) { |
| DCHECK(FLAG_enable_embedded_constant_pool); |
| SetFrameSlot(offset, value); |
| } |
| |
| |
| #undef __ |
| |
| } // namespace internal |
| } // namespace v8 |