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Diffstat (limited to 'chromium/v8/src/x87/deoptimizer-x87.cc')
| -rw-r--r-- | chromium/v8/src/x87/deoptimizer-x87.cc | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/chromium/v8/src/x87/deoptimizer-x87.cc b/chromium/v8/src/x87/deoptimizer-x87.cc new file mode 100644 index 00000000000..36d66497c8d --- /dev/null +++ b/chromium/v8/src/x87/deoptimizer-x87.cc @@ -0,0 +1,406 @@ +// 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/v8.h" + +#if V8_TARGET_ARCH_X87 + +#include "src/codegen.h" +#include "src/deoptimizer.h" +#include "src/full-codegen.h" +#include "src/safepoint-table.h" + +namespace v8 { +namespace internal { + +const int Deoptimizer::table_entry_size_ = 10; + + +int Deoptimizer::patch_size() { + return Assembler::kCallInstructionLength; +} + + +void Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(Handle<Code> code) { + Isolate* isolate = code->GetIsolate(); + HandleScope scope(isolate); + + // Compute the size of relocation information needed for the code + // patching in Deoptimizer::DeoptimizeFunction. + int min_reloc_size = 0; + int prev_pc_offset = 0; + DeoptimizationInputData* deopt_data = + DeoptimizationInputData::cast(code->deoptimization_data()); + for (int i = 0; i < deopt_data->DeoptCount(); i++) { + int pc_offset = deopt_data->Pc(i)->value(); + if (pc_offset == -1) continue; + ASSERT_GE(pc_offset, prev_pc_offset); + int pc_delta = pc_offset - prev_pc_offset; + // We use RUNTIME_ENTRY reloc info which has a size of 2 bytes + // if encodable with small pc delta encoding and up to 6 bytes + // otherwise. + if (pc_delta <= RelocInfo::kMaxSmallPCDelta) { + min_reloc_size += 2; + } else { + min_reloc_size += 6; + } + prev_pc_offset = pc_offset; + } + + // If the relocation information is not big enough we create a new + // relocation info object that is padded with comments to make it + // big enough for lazy doptimization. + int reloc_length = code->relocation_info()->length(); + if (min_reloc_size > reloc_length) { + int comment_reloc_size = RelocInfo::kMinRelocCommentSize; + // Padding needed. + int min_padding = min_reloc_size - reloc_length; + // Number of comments needed to take up at least that much space. + int additional_comments = + (min_padding + comment_reloc_size - 1) / comment_reloc_size; + // Actual padding size. + int padding = additional_comments * comment_reloc_size; + // Allocate new relocation info and copy old relocation to the end + // of the new relocation info array because relocation info is + // written and read backwards. + Factory* factory = isolate->factory(); + Handle<ByteArray> new_reloc = + factory->NewByteArray(reloc_length + padding, TENURED); + MemCopy(new_reloc->GetDataStartAddress() + padding, + code->relocation_info()->GetDataStartAddress(), reloc_length); + // Create a relocation writer to write the comments in the padding + // space. Use position 0 for everything to ensure short encoding. + RelocInfoWriter reloc_info_writer( + new_reloc->GetDataStartAddress() + padding, 0); + intptr_t comment_string + = reinterpret_cast<intptr_t>(RelocInfo::kFillerCommentString); + RelocInfo rinfo(0, RelocInfo::COMMENT, comment_string, NULL); + for (int i = 0; i < additional_comments; ++i) { +#ifdef DEBUG + byte* pos_before = reloc_info_writer.pos(); +#endif + reloc_info_writer.Write(&rinfo); + ASSERT(RelocInfo::kMinRelocCommentSize == + pos_before - reloc_info_writer.pos()); + } + // Replace relocation information on the code object. + code->set_relocation_info(*new_reloc); + } +} + + +void Deoptimizer::PatchCodeForDeoptimization(Isolate* isolate, Code* code) { + Address code_start_address = code->instruction_start(); + + 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(pointer, 1); + patcher.masm()->int3(); + + DeoptimizationInputData* data = + DeoptimizationInputData::cast(code->deoptimization_data()); + int osr_offset = data->OsrPcOffset()->value(); + if (osr_offset > 0) { + CodePatcher osr_patcher(code->instruction_start() + osr_offset, 1); + osr_patcher.masm()->int3(); + } + } + + // We will overwrite the code's relocation info in-place. Relocation info + // is written backward. The relocation info is the payload of a byte + // array. Later on we will slide this to the start of the byte array and + // create a filler object in the remaining space. + ByteArray* reloc_info = code->relocation_info(); + Address reloc_end_address = reloc_info->address() + reloc_info->Size(); + RelocInfoWriter reloc_info_writer(reloc_end_address, code_start_address); + + // Since the call is a relative encoding, write new + // reloc info. We do not need any of the existing reloc info because the + // existing code will not be used again (we zap it in debug builds). + // + // Emit call to lazy deoptimization at all lazy deopt points. + DeoptimizationInputData* deopt_data = + DeoptimizationInputData::cast(code->deoptimization_data()); + SharedFunctionInfo* shared = + SharedFunctionInfo::cast(deopt_data->SharedFunctionInfo()); + shared->EvictFromOptimizedCodeMap(code, "deoptimized code"); +#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; + // Patch lazy deoptimization entry. + Address call_address = code_start_address + deopt_data->Pc(i)->value(); + CodePatcher patcher(call_address, patch_size()); + Address deopt_entry = GetDeoptimizationEntry(isolate, i, LAZY); + patcher.masm()->call(deopt_entry, RelocInfo::NONE32); + // We use RUNTIME_ENTRY for deoptimization bailouts. + RelocInfo rinfo(call_address + 1, // 1 after the call opcode. + RelocInfo::RUNTIME_ENTRY, + reinterpret_cast<intptr_t>(deopt_entry), + NULL); + reloc_info_writer.Write(&rinfo); + ASSERT_GE(reloc_info_writer.pos(), + reloc_info->address() + ByteArray::kHeaderSize); + ASSERT(prev_call_address == NULL || + call_address >= prev_call_address + patch_size()); + ASSERT(call_address + patch_size() <= code->instruction_end()); +#ifdef DEBUG + prev_call_address = call_address; +#endif + } + + // Move the relocation info to the beginning of the byte array. + int new_reloc_size = reloc_end_address - reloc_info_writer.pos(); + MemMove(code->relocation_start(), reloc_info_writer.pos(), new_reloc_size); + + // The relocation info is in place, update the size. + reloc_info->set_length(new_reloc_size); + + // Handle the junk part after the new relocation info. We will create + // a non-live object in the extra space at the end of the former reloc info. + Address junk_address = reloc_info->address() + reloc_info->Size(); + ASSERT(junk_address <= reloc_end_address); + isolate->heap()->CreateFillerObjectAt(junk_address, + reloc_end_address - junk_address); +} + + +void Deoptimizer::FillInputFrame(Address tos, JavaScriptFrame* frame) { + // Set the register values. The values are not important as there are no + // callee saved registers in JavaScript frames, so all registers are + // spilled. Registers ebp and esp are set to the correct values though. + + for (int i = 0; i < Register::kNumRegisters; i++) { + input_->SetRegister(i, i * 4); + } + input_->SetRegister(esp.code(), reinterpret_cast<intptr_t>(frame->sp())); + input_->SetRegister(ebp.code(), reinterpret_cast<intptr_t>(frame->fp())); + for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); i++) { + input_->SetDoubleRegister(i, 0.0); + } + + // Fill the frame content from the actual data on the frame. + for (unsigned i = 0; i < input_->GetFrameSize(); i += kPointerSize) { + input_->SetFrameSlot(i, Memory::uint32_at(tos + i)); + } +} + + +void Deoptimizer::SetPlatformCompiledStubRegisters( + FrameDescription* output_frame, CodeStubInterfaceDescriptor* descriptor) { + intptr_t handler = + reinterpret_cast<intptr_t>(descriptor->deoptimization_handler_); + int params = descriptor->GetHandlerParameterCount(); + output_frame->SetRegister(eax.code(), params); + output_frame->SetRegister(ebx.code(), handler); +} + + +void Deoptimizer::CopyDoubleRegisters(FrameDescription* output_frame) { + // Do nothing for X87. + return; +} + + +bool Deoptimizer::HasAlignmentPadding(JSFunction* function) { + int parameter_count = function->shared()->formal_parameter_count() + 1; + unsigned input_frame_size = input_->GetFrameSize(); + unsigned alignment_state_offset = + input_frame_size - parameter_count * kPointerSize - + StandardFrameConstants::kFixedFrameSize - + kPointerSize; + ASSERT(JavaScriptFrameConstants::kDynamicAlignmentStateOffset == + JavaScriptFrameConstants::kLocal0Offset); + int32_t alignment_state = input_->GetFrameSlot(alignment_state_offset); + return (alignment_state == kAlignmentPaddingPushed); +} + + +#define __ masm()-> + +void Deoptimizer::EntryGenerator::Generate() { + GeneratePrologue(); + + // Save all general purpose registers before messing with them. + const int kNumberOfRegisters = Register::kNumRegisters; + __ pushad(); + + const int kSavedRegistersAreaSize = kNumberOfRegisters * kPointerSize; + + // Get the bailout id from the stack. + __ mov(ebx, Operand(esp, kSavedRegistersAreaSize)); + + // Get the address of the location in the code object + // and compute the fp-to-sp delta in register edx. + __ mov(ecx, Operand(esp, kSavedRegistersAreaSize + 1 * kPointerSize)); + __ lea(edx, Operand(esp, kSavedRegistersAreaSize + 2 * kPointerSize)); + + __ sub(edx, ebp); + __ neg(edx); + + // Allocate a new deoptimizer object. + __ PrepareCallCFunction(6, eax); + __ mov(eax, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset)); + __ mov(Operand(esp, 0 * kPointerSize), eax); // Function. + __ mov(Operand(esp, 1 * kPointerSize), Immediate(type())); // Bailout type. + __ mov(Operand(esp, 2 * kPointerSize), ebx); // Bailout id. + __ mov(Operand(esp, 3 * kPointerSize), ecx); // Code address or 0. + __ mov(Operand(esp, 4 * kPointerSize), edx); // Fp-to-sp delta. + __ mov(Operand(esp, 5 * kPointerSize), + Immediate(ExternalReference::isolate_address(isolate()))); + { + AllowExternalCallThatCantCauseGC scope(masm()); + __ CallCFunction(ExternalReference::new_deoptimizer_function(isolate()), 6); + } + + // Preserve deoptimizer object in register eax and get the input + // frame descriptor pointer. + __ mov(ebx, Operand(eax, Deoptimizer::input_offset())); + + // Fill in the input registers. + for (int i = kNumberOfRegisters - 1; i >= 0; i--) { + int offset = (i * kPointerSize) + FrameDescription::registers_offset(); + __ pop(Operand(ebx, offset)); + } + + // Clear FPU all exceptions. + // TODO(ulan): Find out why the TOP register is not zero here in some cases, + // and check that the generated code never deoptimizes with unbalanced stack. + __ fnclex(); + + // Remove the bailout id, return address and the double registers. + __ add(esp, Immediate(2 * kPointerSize)); + + // Compute a pointer to the unwinding limit in register ecx; that is + // the first stack slot not part of the input frame. + __ mov(ecx, Operand(ebx, FrameDescription::frame_size_offset())); + __ add(ecx, esp); + + // Unwind the stack down to - but not including - the unwinding + // limit and copy the contents of the activation frame to the input + // frame description. + __ lea(edx, Operand(ebx, FrameDescription::frame_content_offset())); + Label pop_loop_header; + __ jmp(&pop_loop_header); + Label pop_loop; + __ bind(&pop_loop); + __ pop(Operand(edx, 0)); + __ add(edx, Immediate(sizeof(uint32_t))); + __ bind(&pop_loop_header); + __ cmp(ecx, esp); + __ j(not_equal, &pop_loop); + + // Compute the output frame in the deoptimizer. + __ push(eax); + __ PrepareCallCFunction(1, ebx); + __ mov(Operand(esp, 0 * kPointerSize), eax); + { + AllowExternalCallThatCantCauseGC scope(masm()); + __ CallCFunction( + ExternalReference::compute_output_frames_function(isolate()), 1); + } + __ pop(eax); + + // If frame was dynamically aligned, pop padding. + Label no_padding; + __ cmp(Operand(eax, Deoptimizer::has_alignment_padding_offset()), + Immediate(0)); + __ j(equal, &no_padding); + __ pop(ecx); + if (FLAG_debug_code) { + __ cmp(ecx, Immediate(kAlignmentZapValue)); + __ Assert(equal, kAlignmentMarkerExpected); + } + __ bind(&no_padding); + + // Replace the current frame with the output frames. + Label outer_push_loop, inner_push_loop, + outer_loop_header, inner_loop_header; + // Outer loop state: eax = current FrameDescription**, edx = one past the + // last FrameDescription**. + __ mov(edx, Operand(eax, Deoptimizer::output_count_offset())); + __ mov(eax, Operand(eax, Deoptimizer::output_offset())); + __ lea(edx, Operand(eax, edx, times_4, 0)); + __ jmp(&outer_loop_header); + __ bind(&outer_push_loop); + // Inner loop state: ebx = current FrameDescription*, ecx = loop index. + __ mov(ebx, Operand(eax, 0)); + __ mov(ecx, Operand(ebx, FrameDescription::frame_size_offset())); + __ jmp(&inner_loop_header); + __ bind(&inner_push_loop); + __ sub(ecx, Immediate(sizeof(uint32_t))); + __ push(Operand(ebx, ecx, times_1, FrameDescription::frame_content_offset())); + __ bind(&inner_loop_header); + __ test(ecx, ecx); + __ j(not_zero, &inner_push_loop); + __ add(eax, Immediate(kPointerSize)); + __ bind(&outer_loop_header); + __ cmp(eax, edx); + __ j(below, &outer_push_loop); + + // Push state, pc, and continuation from the last output frame. + __ push(Operand(ebx, FrameDescription::state_offset())); + __ push(Operand(ebx, FrameDescription::pc_offset())); + __ push(Operand(ebx, FrameDescription::continuation_offset())); + + + // Push the registers from the last output frame. + for (int i = 0; i < kNumberOfRegisters; i++) { + int offset = (i * kPointerSize) + FrameDescription::registers_offset(); + __ push(Operand(ebx, offset)); + } + + // Restore the registers from the stack. + __ popad(); + + // Return to the continuation point. + __ ret(0); +} + + +void Deoptimizer::TableEntryGenerator::GeneratePrologue() { + // Create a sequence of deoptimization entries. + Label done; + for (int i = 0; i < count(); i++) { + int start = masm()->pc_offset(); + USE(start); + __ push_imm32(i); + __ jmp(&done); + ASSERT(masm()->pc_offset() - start == table_entry_size_); + } + __ bind(&done); +} + + +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) { + // No out-of-line constant pool support. + UNREACHABLE(); +} + + +#undef __ + + +} } // namespace v8::internal + +#endif // V8_TARGET_ARCH_X87 |