// Copyright 2011 the V8 project authors. All rights reserved. // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #include "v8.h" #include "codegen.h" #include "deoptimizer.h" #include "full-codegen.h" #include "safepoint-table.h" namespace v8 { namespace internal { int Deoptimizer::table_entry_size_ = 16; int Deoptimizer::patch_size() { const int kCallInstructionSizeInWords = 3; return kCallInstructionSizeInWords * Assembler::kInstrSize; } void Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(Handle code) { // Nothing to do. No new relocation information is written for lazy // deoptimization on ARM. } void Deoptimizer::DeoptimizeFunction(JSFunction* function) { AssertNoAllocation no_allocation; if (!function->IsOptimized()) return; // Get the optimized code. Code* code = function->code(); // Invalidate the relocation information, as it will become invalid by the // code patching below, and is not needed any more. code->InvalidateRelocation(); // For each return after a safepoint insert an absolute call to the // corresponding deoptimization entry. ASSERT(patch_size() % Assembler::kInstrSize == 0); int call_size_in_words = patch_size() / Assembler::kInstrSize; unsigned last_pc_offset = 0; SafepointTable table(function->code()); for (unsigned i = 0; i < table.length(); i++) { unsigned pc_offset = table.GetPcOffset(i); SafepointEntry safepoint_entry = table.GetEntry(i); int deoptimization_index = safepoint_entry.deoptimization_index(); int gap_code_size = safepoint_entry.gap_code_size(); // Check that we did not shoot past next safepoint. // TODO(srdjan): How do we guarantee that safepoint code does not // overlap other safepoint patching code? CHECK(pc_offset >= last_pc_offset); #ifdef DEBUG // Destroy the code which is not supposed to be run again. int instructions = (pc_offset - last_pc_offset) / Assembler::kInstrSize; CodePatcher destroyer(code->instruction_start() + last_pc_offset, instructions); for (int x = 0; x < instructions; x++) { destroyer.masm()->bkpt(0); } #endif last_pc_offset = pc_offset; if (deoptimization_index != Safepoint::kNoDeoptimizationIndex) { last_pc_offset += gap_code_size; CodePatcher patcher(code->instruction_start() + last_pc_offset, call_size_in_words); Address deoptimization_entry = Deoptimizer::GetDeoptimizationEntry( deoptimization_index, Deoptimizer::LAZY); patcher.masm()->Call(deoptimization_entry, RelocInfo::NONE); last_pc_offset += patch_size(); } } #ifdef DEBUG // Destroy the code which is not supposed to be run again. int instructions = (code->safepoint_table_offset() - last_pc_offset) / Assembler::kInstrSize; CodePatcher destroyer(code->instruction_start() + last_pc_offset, instructions); for (int x = 0; x < instructions; x++) { destroyer.masm()->bkpt(0); } #endif // Add the deoptimizing code to the list. DeoptimizingCodeListNode* node = new DeoptimizingCodeListNode(code); node->set_next(deoptimizing_code_list_); deoptimizing_code_list_ = node; // Set the code for the function to non-optimized version. function->ReplaceCode(function->shared()->code()); if (FLAG_trace_deopt) { PrintF("[forced deoptimization: "); function->PrintName(); PrintF(" / %x]\n", reinterpret_cast(function)); } } void Deoptimizer::PatchStackCheckCodeAt(Address pc_after, Code* check_code, Code* replacement_code) { const int kInstrSize = Assembler::kInstrSize; // The call of the stack guard check has the following form: // e1 5d 00 0c cmp sp, // 2a 00 00 01 bcs ok // e5 9f c? ?? ldr ip, [pc, ] // e1 2f ff 3c blx ip ASSERT(Memory::int32_at(pc_after - kInstrSize) == (al | B24 | B21 | 15*B16 | 15*B12 | 15*B8 | BLX | ip.code())); ASSERT(Assembler::IsLdrPcImmediateOffset( Assembler::instr_at(pc_after - 2 * kInstrSize))); // We patch the code to the following form: // e1 5d 00 0c cmp sp, // e1 a0 00 00 mov r0, r0 (NOP) // e5 9f c? ?? ldr ip, [pc, ] // e1 2f ff 3c blx ip // and overwrite the constant containing the // address of the stack check stub. // Replace conditional jump with NOP. CodePatcher patcher(pc_after - 3 * kInstrSize, 1); patcher.masm()->nop(); // Replace the stack check address in the constant pool // with the entry address of the replacement code. uint32_t stack_check_address_offset = Memory::uint16_at(pc_after - 2 * kInstrSize) & 0xfff; Address stack_check_address_pointer = pc_after + stack_check_address_offset; ASSERT(Memory::uint32_at(stack_check_address_pointer) == reinterpret_cast(check_code->entry())); Memory::uint32_at(stack_check_address_pointer) = reinterpret_cast(replacement_code->entry()); } void Deoptimizer::RevertStackCheckCodeAt(Address pc_after, Code* check_code, Code* replacement_code) { const int kInstrSize = Assembler::kInstrSize; ASSERT(Memory::uint32_at(pc_after - kInstrSize) == 0xe12fff3c); ASSERT(Memory::uint8_at(pc_after - kInstrSize - 1) == 0xe5); ASSERT(Memory::uint8_at(pc_after - kInstrSize - 2) == 0x9f); // Replace NOP with conditional jump. CodePatcher patcher(pc_after - 3 * kInstrSize, 1); patcher.masm()->b(+4, cs); // Replace the stack check address in the constant pool // with the entry address of the replacement code. uint32_t stack_check_address_offset = Memory::uint16_at(pc_after - 2 * kInstrSize) & 0xfff; Address stack_check_address_pointer = pc_after + stack_check_address_offset; ASSERT(Memory::uint32_at(stack_check_address_pointer) == reinterpret_cast(replacement_code->entry())); Memory::uint32_at(stack_check_address_pointer) = reinterpret_cast(check_code->entry()); } static int LookupBailoutId(DeoptimizationInputData* data, unsigned ast_id) { ByteArray* translations = data->TranslationByteArray(); int length = data->DeoptCount(); for (int i = 0; i < length; i++) { if (static_cast(data->AstId(i)->value()) == ast_id) { TranslationIterator it(translations, data->TranslationIndex(i)->value()); int value = it.Next(); ASSERT(Translation::BEGIN == static_cast(value)); // Read the number of frames. value = it.Next(); if (value == 1) return i; } } UNREACHABLE(); return -1; } void Deoptimizer::DoComputeOsrOutputFrame() { DeoptimizationInputData* data = DeoptimizationInputData::cast( optimized_code_->deoptimization_data()); unsigned ast_id = data->OsrAstId()->value(); int bailout_id = LookupBailoutId(data, ast_id); unsigned translation_index = data->TranslationIndex(bailout_id)->value(); ByteArray* translations = data->TranslationByteArray(); TranslationIterator iterator(translations, translation_index); Translation::Opcode opcode = static_cast(iterator.Next()); ASSERT(Translation::BEGIN == opcode); USE(opcode); int count = iterator.Next(); ASSERT(count == 1); USE(count); opcode = static_cast(iterator.Next()); USE(opcode); ASSERT(Translation::FRAME == opcode); unsigned node_id = iterator.Next(); USE(node_id); ASSERT(node_id == ast_id); JSFunction* function = JSFunction::cast(ComputeLiteral(iterator.Next())); USE(function); ASSERT(function == function_); unsigned height = iterator.Next(); unsigned height_in_bytes = height * kPointerSize; USE(height_in_bytes); unsigned fixed_size = ComputeFixedSize(function_); unsigned input_frame_size = input_->GetFrameSize(); ASSERT(fixed_size + height_in_bytes == input_frame_size); unsigned stack_slot_size = optimized_code_->stack_slots() * kPointerSize; unsigned outgoing_height = data->ArgumentsStackHeight(bailout_id)->value(); unsigned outgoing_size = outgoing_height * kPointerSize; unsigned output_frame_size = fixed_size + stack_slot_size + outgoing_size; ASSERT(outgoing_size == 0); // OSR does not happen in the middle of a call. if (FLAG_trace_osr) { PrintF("[on-stack replacement: begin 0x%08" V8PRIxPTR " ", reinterpret_cast(function_)); function_->PrintName(); PrintF(" => node=%u, frame=%d->%d]\n", ast_id, input_frame_size, output_frame_size); } // There's only one output frame in the OSR case. output_count_ = 1; output_ = new FrameDescription*[1]; output_[0] = new(output_frame_size) FrameDescription( output_frame_size, function_); // Clear the incoming parameters in the optimized frame to avoid // confusing the garbage collector. unsigned output_offset = output_frame_size - kPointerSize; int parameter_count = function_->shared()->formal_parameter_count() + 1; for (int i = 0; i < parameter_count; ++i) { output_[0]->SetFrameSlot(output_offset, 0); output_offset -= kPointerSize; } // Translate the incoming parameters. This may overwrite some of the // incoming argument slots we've just cleared. int input_offset = input_frame_size - kPointerSize; bool ok = true; int limit = input_offset - (parameter_count * kPointerSize); while (ok && input_offset > limit) { ok = DoOsrTranslateCommand(&iterator, &input_offset); } // There are no translation commands for the caller's pc and fp, the // context, and the function. Set them up explicitly. for (int i = 0; ok && i < 4; i++) { uint32_t input_value = input_->GetFrameSlot(input_offset); if (FLAG_trace_osr) { PrintF(" [sp + %d] <- 0x%08x ; [sp + %d] (fixed part)\n", output_offset, input_value, input_offset); } output_[0]->SetFrameSlot(output_offset, input_->GetFrameSlot(input_offset)); input_offset -= kPointerSize; output_offset -= kPointerSize; } // Translate the rest of the frame. while (ok && input_offset >= 0) { ok = DoOsrTranslateCommand(&iterator, &input_offset); } // If translation of any command failed, continue using the input frame. if (!ok) { delete output_[0]; output_[0] = input_; output_[0]->SetPc(reinterpret_cast(from_)); } else { // Setup the frame pointer and the context pointer. output_[0]->SetRegister(fp.code(), input_->GetRegister(fp.code())); output_[0]->SetRegister(cp.code(), input_->GetRegister(cp.code())); unsigned pc_offset = data->OsrPcOffset()->value(); uint32_t pc = reinterpret_cast( optimized_code_->entry() + pc_offset); output_[0]->SetPc(pc); } Code* continuation = Builtins::builtin(Builtins::NotifyOSR); output_[0]->SetContinuation( reinterpret_cast(continuation->entry())); if (FLAG_trace_osr) { PrintF("[on-stack replacement translation %s: 0x%08" V8PRIxPTR " ", ok ? "finished" : "aborted", reinterpret_cast(function)); function->PrintName(); PrintF(" => pc=0x%0x]\n", output_[0]->GetPc()); } } // This code is very similar to ia32 code, but relies on register names (fp, sp) // and how the frame is laid out. void Deoptimizer::DoComputeFrame(TranslationIterator* iterator, int frame_index) { // Read the ast node id, function, and frame height for this output frame. Translation::Opcode opcode = static_cast(iterator->Next()); USE(opcode); ASSERT(Translation::FRAME == opcode); int node_id = iterator->Next(); JSFunction* function = JSFunction::cast(ComputeLiteral(iterator->Next())); unsigned height = iterator->Next(); unsigned height_in_bytes = height * kPointerSize; if (FLAG_trace_deopt) { PrintF(" translating "); function->PrintName(); PrintF(" => node=%d, height=%d\n", node_id, height_in_bytes); } // The 'fixed' part of the frame consists of the incoming parameters and // the part described by JavaScriptFrameConstants. unsigned fixed_frame_size = ComputeFixedSize(function); unsigned input_frame_size = input_->GetFrameSize(); unsigned output_frame_size = height_in_bytes + fixed_frame_size; // Allocate and store the output frame description. FrameDescription* output_frame = new(output_frame_size) FrameDescription(output_frame_size, function); bool is_bottommost = (0 == frame_index); bool is_topmost = (output_count_ - 1 == frame_index); ASSERT(frame_index >= 0 && frame_index < output_count_); ASSERT(output_[frame_index] == NULL); output_[frame_index] = output_frame; // The top address for the bottommost output frame can be computed from // the input frame pointer and the output frame's height. For all // subsequent output frames, it can be computed from the previous one's // top address and the current frame's size. uint32_t top_address; if (is_bottommost) { // 2 = context and function in the frame. top_address = input_->GetRegister(fp.code()) - (2 * kPointerSize) - height_in_bytes; } else { top_address = output_[frame_index - 1]->GetTop() - output_frame_size; } output_frame->SetTop(top_address); // Compute the incoming parameter translation. int parameter_count = function->shared()->formal_parameter_count() + 1; unsigned output_offset = output_frame_size; unsigned input_offset = input_frame_size; for (int i = 0; i < parameter_count; ++i) { output_offset -= kPointerSize; DoTranslateCommand(iterator, frame_index, output_offset); } input_offset -= (parameter_count * kPointerSize); // There are no translation commands for the caller's pc and fp, the // context, and the function. Synthesize their values and set them up // explicitly. // // The caller's pc for the bottommost output frame is the same as in the // input frame. For all subsequent output frames, it can be read from the // previous one. This frame's pc can be computed from the non-optimized // function code and AST id of the bailout. output_offset -= kPointerSize; input_offset -= kPointerSize; intptr_t value; if (is_bottommost) { value = input_->GetFrameSlot(input_offset); } else { value = output_[frame_index - 1]->GetPc(); } output_frame->SetFrameSlot(output_offset, value); if (FLAG_trace_deopt) { PrintF(" 0x%08x: [top + %d] <- 0x%08x ; caller's pc\n", top_address + output_offset, output_offset, value); } // The caller's frame pointer for the bottommost output frame is the same // as in the input frame. For all subsequent output frames, it can be // read from the previous one. Also compute and set this frame's frame // pointer. output_offset -= kPointerSize; input_offset -= kPointerSize; if (is_bottommost) { value = input_->GetFrameSlot(input_offset); } else { value = output_[frame_index - 1]->GetFp(); } output_frame->SetFrameSlot(output_offset, value); intptr_t fp_value = top_address + output_offset; ASSERT(!is_bottommost || input_->GetRegister(fp.code()) == fp_value); output_frame->SetFp(fp_value); if (is_topmost) { output_frame->SetRegister(fp.code(), fp_value); } if (FLAG_trace_deopt) { PrintF(" 0x%08x: [top + %d] <- 0x%08x ; caller's fp\n", fp_value, output_offset, value); } // For the bottommost output frame the context can be gotten from the input // frame. For all subsequent output frames it can be gotten from the function // so long as we don't inline functions that need local contexts. output_offset -= kPointerSize; input_offset -= kPointerSize; if (is_bottommost) { value = input_->GetFrameSlot(input_offset); } else { value = reinterpret_cast(function->context()); } output_frame->SetFrameSlot(output_offset, value); if (is_topmost) { output_frame->SetRegister(cp.code(), value); } if (FLAG_trace_deopt) { PrintF(" 0x%08x: [top + %d] <- 0x%08x ; context\n", top_address + output_offset, output_offset, value); } // The function was mentioned explicitly in the BEGIN_FRAME. output_offset -= kPointerSize; input_offset -= kPointerSize; value = reinterpret_cast(function); // The function for the bottommost output frame should also agree with the // input frame. ASSERT(!is_bottommost || input_->GetFrameSlot(input_offset) == value); output_frame->SetFrameSlot(output_offset, value); if (FLAG_trace_deopt) { PrintF(" 0x%08x: [top + %d] <- 0x%08x ; function\n", top_address + output_offset, output_offset, value); } // Translate the rest of the frame. for (unsigned i = 0; i < height; ++i) { output_offset -= kPointerSize; DoTranslateCommand(iterator, frame_index, output_offset); } ASSERT(0 == output_offset); // Compute this frame's PC, state, and continuation. Code* non_optimized_code = function->shared()->code(); FixedArray* raw_data = non_optimized_code->deoptimization_data(); DeoptimizationOutputData* data = DeoptimizationOutputData::cast(raw_data); Address start = non_optimized_code->instruction_start(); unsigned pc_and_state = GetOutputInfo(data, node_id, function->shared()); unsigned pc_offset = FullCodeGenerator::PcField::decode(pc_and_state); uint32_t pc_value = reinterpret_cast(start + pc_offset); output_frame->SetPc(pc_value); if (is_topmost) { output_frame->SetRegister(pc.code(), pc_value); } FullCodeGenerator::State state = FullCodeGenerator::StateField::decode(pc_and_state); output_frame->SetState(Smi::FromInt(state)); // Set the continuation for the topmost frame. if (is_topmost) { Code* continuation = (bailout_type_ == EAGER) ? Builtins::builtin(Builtins::NotifyDeoptimized) : Builtins::builtin(Builtins::NotifyLazyDeoptimized); output_frame->SetContinuation( reinterpret_cast(continuation->entry())); } if (output_count_ - 1 == frame_index) iterator->Done(); } #define __ masm()-> // This code tries to be close to ia32 code so that any changes can be // easily ported. void Deoptimizer::EntryGenerator::Generate() { GeneratePrologue(); CpuFeatures::Scope scope(VFP3); // 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::kNumAllocatableRegisters; // Save all general purpose registers before messing with them. __ sub(sp, sp, Operand(kDoubleRegsSize)); for (int i = 0; i < DwVfpRegister::kNumAllocatableRegisters; ++i) { DwVfpRegister vfp_reg = DwVfpRegister::FromAllocationIndex(i); int offset = i * kDoubleSize; __ vstr(vfp_reg, sp, offset); } // Push all 16 registers (needed to populate FrameDescription::registers_). __ stm(db_w, sp, restored_regs | sp.bit() | lr.bit() | pc.bit()); 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 if possible (r3) (return // address for lazy deoptimization) and compute the fp-to-sp delta in // register r4. if (type() == EAGER) { __ mov(r3, Operand(0)); // Correct one word for bailout id. __ add(r4, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize))); } else if (type() == OSR) { __ mov(r3, lr); // Correct one word for bailout id. __ add(r4, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize))); } else { __ mov(r3, lr); // Correct two words for bailout id and return address. __ add(r4, sp, Operand(kSavedRegistersAreaSize + (2 * kPointerSize))); } __ sub(r4, fp, r4); // Allocate a new deoptimizer object. // Pass four arguments in r0 to r3 and fifth argument on stack. __ PrepareCallCFunction(5, r5); __ ldr(r0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset)); __ 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. // Call Deoptimizer::New(). __ CallCFunction(ExternalReference::new_deoptimizer_function(), 5); // 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]. ASSERT(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::kNumAllocatableRegisters] int double_regs_offset = FrameDescription::double_registers_offset(); for (int i = 0; i < DwVfpRegister::kNumAllocatableRegisters; ++i) { int dst_offset = i * kDoubleSize + double_regs_offset; int src_offset = i * kDoubleSize + kNumberOfRegisters * kPointerSize; __ vldr(d0, sp, src_offset); __ vstr(d0, r1, dst_offset); } // Remove the bailout id, eventually return address, and the saved registers // from the stack. if (type() == EAGER || type() == OSR) { __ add(sp, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize))); } else { __ add(sp, sp, Operand(kSavedRegistersAreaSize + (2 * 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; __ bind(&pop_loop); __ pop(r4); __ str(r4, MemOperand(r3, 0)); __ add(r3, r3, Operand(sizeof(uint32_t))); __ 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(). __ CallCFunction(ExternalReference::compute_output_frames_function(), 1); __ pop(r0); // Restore deoptimizer object (class Deoptimizer). // Replace the current (input) frame with the output frames. Label outer_push_loop, inner_push_loop; // Outer loop state: r0 = current "FrameDescription** output_", // r1 = one past the last FrameDescription**. __ ldr(r1, MemOperand(r0, Deoptimizer::output_count_offset())); __ ldr(r0, MemOperand(r0, Deoptimizer::output_offset())); // r0 is output_. __ add(r1, r0, Operand(r1, LSL, 2)); __ bind(&outer_push_loop); // Inner loop state: r2 = current FrameDescription*, r3 = loop index. __ ldr(r2, MemOperand(r0, 0)); // output_[ix] __ ldr(r3, MemOperand(r2, FrameDescription::frame_size_offset())); __ bind(&inner_push_loop); __ sub(r3, r3, Operand(sizeof(uint32_t))); // __ add(r6, r2, Operand(r3, LSL, 1)); __ add(r6, r2, Operand(r3)); __ ldr(r7, MemOperand(r6, FrameDescription::frame_content_offset())); __ push(r7); __ cmp(r3, Operand(0)); __ b(ne, &inner_push_loop); // test for gt? __ add(r0, r0, Operand(kPointerSize)); __ cmp(r0, r1); __ b(lt, &outer_push_loop); // Push state, pc, and continuation from the last output frame. if (type() != OSR) { __ 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 // Set up the roots register. ExternalReference roots_address = ExternalReference::roots_address(); __ mov(r10, Operand(roots_address)); __ pop(ip); // remove pc __ pop(r7); // get continuation, leave pc on stack __ pop(lr); __ Jump(r7); __ stop("Unreachable."); } void Deoptimizer::TableEntryGenerator::GeneratePrologue() { // Create a sequence of deoptimization entries. Note that any // registers may be still live. Label done; for (int i = 0; i < count(); i++) { int start = masm()->pc_offset(); USE(start); if (type() == EAGER) { __ nop(); } else { // Emulate ia32 like call by pushing return address to stack. __ push(lr); } __ mov(ip, Operand(i)); __ push(ip); __ b(&done); ASSERT(masm()->pc_offset() - start == table_entry_size_); } __ bind(&done); } #undef __ } } // namespace v8::internal