[debugger] infrastructure for side-effect-free debug-evaluate.

src/arm64/macro-assembler-arm64.cc

 // Copyright 2013 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_ARM64
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 2348 matching lines @@
         // MAsm::InvokeFunctionCode and we can just fall through.
         B(done);
       }
     } else {
       Jump(adaptor, RelocInfo::CODE_TARGET);
     }
   }
   Bind(&regular_invoke);
 }
 
-
-void MacroAssembler::FloodFunctionIfStepping(Register fun, Register new_target,
-                                             const ParameterCount& expected,
-                                             const ParameterCount& actual) {
-  Label skip_flooding;
-  ExternalReference last_step_action =
-      ExternalReference::debug_last_step_action_address(isolate());
-  STATIC_ASSERT(StepFrame > StepIn);
-  Mov(x4, Operand(last_step_action));
+void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
+                                    const ParameterCount& expected,
+                                    const ParameterCount& actual) {
+  Label skip_hook;
+  ExternalReference debug_hook_active =
+      ExternalReference::debug_hook_on_function_call_address(isolate());
+  Mov(x4, Operand(debug_hook_active));
   Ldrsb(x4, MemOperand(x4));
-  CompareAndBranch(x4, Operand(StepIn), lt, &skip_flooding);
+  CompareAndBranch(x4, Operand(0), eq, &skip_hook);
   {
     FrameScope frame(this,
                      has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
     if (expected.is_reg()) {
       SmiTag(expected.reg());
       Push(expected.reg());
     }
     if (actual.is_reg()) {
       SmiTag(actual.reg());
       Push(actual.reg());
     }
     if (new_target.is_valid()) {
       Push(new_target);
     }
     Push(fun);
     Push(fun);
-    CallRuntime(Runtime::kDebugPrepareStepInIfStepping);
+    CallRuntime(Runtime::kDebugOnFunctionCall);
     Pop(fun);
     if (new_target.is_valid()) {
       Pop(new_target);
     }
     if (actual.is_reg()) {
       Pop(actual.reg());
       SmiUntag(actual.reg());
     }
     if (expected.is_reg()) {
       Pop(expected.reg());
       SmiUntag(expected.reg());
     }
   }
-  bind(&skip_flooding);
+  bind(&skip_hook);
 }
 
 
 void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
                                         const ParameterCount& expected,
                                         const ParameterCount& actual,
                                         InvokeFlag flag,
                                         const CallWrapper& call_wrapper) {
   // You can't call a function without a valid frame.
   DCHECK(flag == JUMP_FUNCTION || has_frame());
   DCHECK(function.is(x1));
   DCHECK_IMPLIES(new_target.is_valid(), new_target.is(x3));
 
-  FloodFunctionIfStepping(function, new_target, expected, actual);
+  if (call_wrapper.NeedsDebugHookCheck()) {
+    CheckDebugHook(function, new_target, expected, actual);
+  }
 
   // Clear the new.target register if not given.
   if (!new_target.is_valid()) {
     LoadRoot(x3, Heap::kUndefinedValueRootIndex);
   }
 
   Label done;
   bool definitely_mismatches = false;
   InvokePrologue(expected, actual, &done, flag, &definitely_mismatches,
                  call_wrapper);
@@ skipping 2233 matching lines @@
 }
 
 
 #undef __
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64