| // 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_X64 |
| |
| #include "src/assembler.h" |
| #include "src/codegen.h" |
| #include "src/debug/debug.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); |
| Label check_codesize; |
| patcher.masm()->bind(&check_codesize); |
| patcher.masm()->movp(kScratchRegister, reinterpret_cast<void*>(code->entry()), |
| Assembler::RelocInfoNone()); |
| patcher.masm()->call(kScratchRegister); |
| // 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(Smi::FromInt(LiveEdit::kFramePaddingValue)); |
| } |
| __ Push(Smi::FromInt(LiveEdit::kFramePaddingInitialSize)); |
| |
| if (mode == SAVE_RESULT_REGISTER) __ Push(rax); |
| |
| __ Set(rax, 0); // No arguments (argc == 0). |
| __ Move(rbx, 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)}; |
| __ Set(reg, kDebugZapValue); |
| } |
| } |
| |
| if (mode == SAVE_RESULT_REGISTER) __ Pop(rax); |
| |
| // Read current padding counter and skip corresponding number of words. |
| __ Pop(kScratchRegister); |
| __ SmiToInteger32(kScratchRegister, kScratchRegister); |
| __ leap(rsp, Operand(rsp, kScratchRegister, times_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. |
| __ addp(rsp, Immediate(kPCOnStackSize)); |
| |
| // 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()); |
| __ Move(kScratchRegister, after_break_target); |
| __ Jump(Operand(kScratchRegister, 0)); |
| } |
| |
| |
| void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) { |
| // We do not know our frame height, but set rsp based on rbp. |
| __ leap(rsp, Operand(rbp, -1 * kPointerSize)); |
| |
| __ Pop(rdi); // Function. |
| __ popq(rbp); |
| |
| ParameterCount dummy(0); |
| __ FloodFunctionIfStepping(rdi, no_reg, dummy, dummy); |
| |
| // Load context from the function. |
| __ movp(rsi, FieldOperand(rdi, JSFunction::kContextOffset)); |
| |
| // Clear new.target as a safety measure. |
| __ LoadRoot(rdx, Heap::kUndefinedValueRootIndex); |
| |
| // Get function code. |
| __ movp(rbx, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset)); |
| __ movp(rbx, FieldOperand(rbx, SharedFunctionInfo::kCodeOffset)); |
| __ leap(rbx, FieldOperand(rbx, Code::kHeaderSize)); |
| |
| // Re-run JSFunction, rdi is function, rsi is context. |
| __ jmp(rbx); |
| } |
| |
| const bool LiveEdit::kFrameDropperSupported = true; |
| |
| #undef __ |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_TARGET_ARCH_X64 |