| // 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_ARM |
| |
| #include "src/codegen.h" |
| #include "src/debug/debug.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| #define __ ACCESS_MASM(masm) |
| |
| |
| void EmitDebugBreakSlot(MacroAssembler* masm) { |
| Label check_size; |
| __ bind(&check_size); |
| for (int i = 0; i < Assembler::kDebugBreakSlotInstructions; i++) { |
| __ nop(MacroAssembler::DEBUG_BREAK_NOP); |
| } |
| DCHECK_EQ(Assembler::kDebugBreakSlotInstructions, |
| masm->InstructionsGeneratedSince(&check_size)); |
| } |
| |
| |
| void DebugCodegen::GenerateSlot(MacroAssembler* masm, RelocInfo::Mode mode) { |
| // Generate enough nop's to make space for a call instruction. Avoid emitting |
| // the constant pool in the debug break slot code. |
| Assembler::BlockConstPoolScope block_const_pool(masm); |
| masm->RecordDebugBreakSlot(mode); |
| EmitDebugBreakSlot(masm); |
| } |
| |
| |
| void DebugCodegen::ClearDebugBreakSlot(Isolate* isolate, Address pc) { |
| CodePatcher patcher(isolate, pc, Assembler::kDebugBreakSlotInstructions); |
| EmitDebugBreakSlot(patcher.masm()); |
| } |
| |
| |
| void DebugCodegen::PatchDebugBreakSlot(Isolate* isolate, Address pc, |
| Handle<Code> code) { |
| DCHECK_EQ(Code::BUILTIN, code->kind()); |
| CodePatcher patcher(isolate, pc, Assembler::kDebugBreakSlotInstructions); |
| // Patch the code changing the debug break slot code from |
| // mov r2, r2 |
| // mov r2, r2 |
| // mov r2, r2 |
| // mov r2, r2 |
| // to a call to the debug break slot code. |
| // ldr ip, [pc, #0] |
| // b skip |
| // <debug break slot code entry point address> |
| // skip: |
| // blx ip |
| Label skip_constant; |
| patcher.masm()->ldr(ip, MemOperand(v8::internal::pc, 0)); |
| patcher.masm()->b(&skip_constant); |
| patcher.Emit(code->entry()); |
| patcher.masm()->bind(&skip_constant); |
| patcher.masm()->blx(ip); |
| } |
| |
| |
| void DebugCodegen::GenerateDebugBreakStub(MacroAssembler* masm, |
| DebugBreakCallHelperMode mode) { |
| __ RecordComment("Debug break"); |
| { |
| FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL); |
| |
| // Load padding words on stack. |
| __ mov(ip, Operand(Smi::FromInt(LiveEdit::kFramePaddingValue))); |
| for (int i = 0; i < LiveEdit::kFramePaddingInitialSize; i++) { |
| __ push(ip); |
| } |
| __ mov(ip, Operand(Smi::FromInt(LiveEdit::kFramePaddingInitialSize))); |
| __ push(ip); |
| |
| if (mode == SAVE_RESULT_REGISTER) __ push(r0); |
| |
| __ mov(r0, Operand::Zero()); // no arguments |
| __ mov(r1, |
| Operand(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)}; |
| __ mov(reg, Operand(kDebugZapValue)); |
| } |
| } |
| |
| if (mode == SAVE_RESULT_REGISTER) __ pop(r0); |
| |
| // Don't bother removing padding bytes pushed on the stack |
| // as the frame is going to be restored right away. |
| |
| // Leave the internal frame. |
| } |
| |
| // 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()); |
| __ mov(ip, Operand(after_break_target)); |
| __ ldr(ip, MemOperand(ip)); |
| __ Jump(ip); |
| } |
| |
| |
| void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) { |
| // Load the function pointer off of our current stack frame. |
| __ ldr(r1, MemOperand(fp, |
| StandardFrameConstants::kConstantPoolOffset - kPointerSize)); |
| |
| // Pop return address, frame and constant pool pointer (if |
| // FLAG_enable_embedded_constant_pool). |
| __ LeaveFrame(StackFrame::INTERNAL); |
| |
| ParameterCount dummy(0); |
| __ FloodFunctionIfStepping(r1, no_reg, dummy, dummy); |
| |
| { ConstantPoolUnavailableScope constant_pool_unavailable(masm); |
| // Load context from the function. |
| __ ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset)); |
| |
| // Clear new.target as a safety measure. |
| __ LoadRoot(r3, Heap::kUndefinedValueRootIndex); |
| |
| // Get function code. |
| __ ldr(ip, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset)); |
| __ ldr(ip, FieldMemOperand(ip, SharedFunctionInfo::kCodeOffset)); |
| __ add(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag)); |
| |
| // Re-run JSFunction, r1 is function, cp is context. |
| __ Jump(ip); |
| } |
| } |
| |
| |
| const bool LiveEdit::kFrameDropperSupported = true; |
| |
| #undef __ |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_TARGET_ARCH_ARM |