| // 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. |
| |
| #if V8_TARGET_ARCH_IA32 |
| |
| #include "src/codegen.h" |
| #include "src/debug/debug.h" |
| #include "src/ia32/frames-ia32.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| #define __ ACCESS_MASM(masm) |
| |
| |
| void EmitDebugBreakSlot(MacroAssembler* masm) { |
| Label check_codesize; |
| __ bind(&check_codesize); |
| __ Nop(Assembler::kDebugBreakSlotLength); |
| DCHECK_EQ(Assembler::kDebugBreakSlotLength, |
| masm->SizeOfCodeGeneratedSince(&check_codesize)); |
| } |
| |
| |
| void DebugCodegen::GenerateSlot(MacroAssembler* masm, RelocInfo::Mode mode) { |
| // Generate enough nop's to make space for a call instruction. |
| masm->RecordDebugBreakSlot(mode); |
| EmitDebugBreakSlot(masm); |
| } |
| |
| |
| void DebugCodegen::ClearDebugBreakSlot(Isolate* isolate, Address pc) { |
| CodePatcher patcher(isolate, pc, Assembler::kDebugBreakSlotLength); |
| EmitDebugBreakSlot(patcher.masm()); |
| } |
| |
| |
| void DebugCodegen::PatchDebugBreakSlot(Isolate* isolate, Address pc, |
| Handle<Code> code) { |
| DCHECK_EQ(Code::BUILTIN, code->kind()); |
| static const int kSize = Assembler::kDebugBreakSlotLength; |
| CodePatcher patcher(isolate, pc, kSize); |
| |
| // Add a label for checking the size of the code used for returning. |
| Label check_codesize; |
| patcher.masm()->bind(&check_codesize); |
| patcher.masm()->call(code->entry(), RelocInfo::NONE32); |
| // Check that the size of the code generated is as expected. |
| DCHECK_EQ(kSize, patcher.masm()->SizeOfCodeGeneratedSince(&check_codesize)); |
| } |
| |
| bool DebugCodegen::DebugBreakSlotIsPatched(Address pc) { |
| return !Assembler::IsNop(pc); |
| } |
| |
| void DebugCodegen::GenerateDebugBreakStub(MacroAssembler* masm, |
| DebugBreakCallHelperMode mode) { |
| __ RecordComment("Debug break"); |
| |
| // Enter an internal frame. |
| { |
| FrameScope scope(masm, StackFrame::INTERNAL); |
| |
| // Load padding words on stack. |
| for (int i = 0; i < LiveEdit::kFramePaddingInitialSize; i++) { |
| __ push(Immediate(Smi::FromInt(LiveEdit::kFramePaddingValue))); |
| } |
| __ push(Immediate(Smi::FromInt(LiveEdit::kFramePaddingInitialSize))); |
| |
| // Push arguments for DebugBreak call. |
| if (mode == SAVE_RESULT_REGISTER) { |
| // Break on return. |
| __ push(eax); |
| } else { |
| // Non-return breaks. |
| __ Push(masm->isolate()->factory()->the_hole_value()); |
| } |
| __ Move(eax, Immediate(1)); |
| __ mov(ebx, |
| Immediate(ExternalReference( |
| Runtime::FunctionForId(Runtime::kDebugBreak), masm->isolate()))); |
| |
| CEntryStub ceb(masm->isolate(), 1); |
| __ CallStub(&ceb); |
| |
| if (FLAG_debug_code) { |
| for (int i = 0; i < kNumJSCallerSaved; ++i) { |
| Register reg = {JSCallerSavedCode(i)}; |
| // Do not clobber eax if mode is SAVE_RESULT_REGISTER. It will |
| // contain return value of the function. |
| if (!(reg.is(eax) && (mode == SAVE_RESULT_REGISTER))) { |
| __ Move(reg, Immediate(kDebugZapValue)); |
| } |
| } |
| } |
| |
| __ pop(ebx); |
| // We divide stored value by 2 (untagging) and multiply it by word's size. |
| STATIC_ASSERT(kSmiTagSize == 1 && kSmiShiftSize == 0); |
| __ lea(esp, Operand(esp, ebx, times_half_pointer_size, 0)); |
| |
| // Get rid of the internal frame. |
| } |
| |
| // This call did not replace a call , so there will be an unwanted |
| // return address left on the stack. Here we get rid of that. |
| __ add(esp, Immediate(kPointerSize)); |
| |
| // Now that the break point has been handled, resume normal execution by |
| // jumping to the target address intended by the caller and that was |
| // overwritten by the address of DebugBreakXXX. |
| ExternalReference after_break_target = |
| ExternalReference::debug_after_break_target_address(masm->isolate()); |
| __ jmp(Operand::StaticVariable(after_break_target)); |
| } |
| |
| |
| void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) { |
| // We do not know our frame height, but set esp based on ebp. |
| __ lea(esp, Operand(ebp, FrameDropperFrameConstants::kFunctionOffset)); |
| __ pop(edi); // Function. |
| __ add(esp, Immediate(-FrameDropperFrameConstants::kCodeOffset)); // INTERNAL |
| // frame |
| // marker |
| // and code |
| __ pop(ebp); |
| |
| ParameterCount dummy(0); |
| __ FloodFunctionIfStepping(edi, no_reg, dummy, dummy); |
| |
| // Load context from the function. |
| __ mov(esi, FieldOperand(edi, JSFunction::kContextOffset)); |
| |
| // Clear new.target register as a safety measure. |
| __ mov(edx, masm->isolate()->factory()->undefined_value()); |
| |
| // Get function code. |
| __ mov(ebx, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset)); |
| __ mov(ebx, FieldOperand(ebx, SharedFunctionInfo::kCodeOffset)); |
| __ lea(ebx, FieldOperand(ebx, Code::kHeaderSize)); |
| |
| // Re-run JSFunction, edi is function, esi is context. |
| __ jmp(ebx); |
| } |
| |
| |
| const bool LiveEdit::kFrameDropperSupported = true; |
| |
| #undef __ |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_TARGET_ARCH_IA32 |