[runtime] Unify and simplify how frames are marked

src/debug/x64/debug-x64.cc

 // 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"
 
@@ skipping 93 matching lines @@
   // 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));
-
+  __ leap(rsp, Operand(rbp, FrameDropperFrameConstants::kFunctionOffset));
   __ Pop(rdi);  // Function.
+  __ addp(rsp,
+          Immediate(-FrameDropperFrameConstants::kCodeOffset));  // INTERNAL
+                                                                 // frame marker
+                                                                 // and code
   __ 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