X87: [debugger] infrastructure for side-effect-free debug-evaluate.

  port aa75904e (r42270)

  original commit message:

BUG=

Review-Url: https://codereview.chromium.org/2626043005
Cr-Commit-Position: refs/heads/master@{#42352}

src/builtins/x87/builtins-x87.cc

@@ -393,11 +393,10 @@ void Builtins::Generate_ResumeGeneratorTrampoline(MacroAssembler* masm) {
   // Flood function if we are stepping.
   Label prepare_step_in_if_stepping, prepare_step_in_suspended_generator;
   Label stepping_prepared;
-  ExternalReference last_step_action =
-      ExternalReference::debug_last_step_action_address(masm->isolate());
-  STATIC_ASSERT(StepFrame > StepIn);
-  __ cmpb(Operand::StaticVariable(last_step_action), Immediate(StepIn));
-  __ j(greater_equal, &prepare_step_in_if_stepping);
+  ExternalReference debug_hook =
+      ExternalReference::debug_hook_on_function_call_address(masm->isolate());
+  __ cmpb(Operand::StaticVariable(debug_hook), Immediate(0));
+  __ j(not_equal, &prepare_step_in_if_stepping);
 
   // Flood function if we need to continue stepping in the suspended generator.
   ExternalReference debug_suspended_generator =
@@ -465,7 +464,7 @@ void Builtins::Generate_ResumeGeneratorTrampoline(MacroAssembler* masm) {
     __ Push(ebx);
     __ Push(edx);
     __ Push(edi);
-    __ CallRuntime(Runtime::kDebugPrepareStepInIfStepping);
+    __ CallRuntime(Runtime::kDebugOnFunctionCall);
     __ Pop(edx);
     __ Pop(ebx);
     __ mov(edi, FieldOperand(ebx, JSGeneratorObject::kFunctionOffset));

src/debug/x87/debug-x87.cc

@@ -129,7 +129,7 @@ void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) {
   __ pop(ebp);
 
   ParameterCount dummy(0);
-  __ FloodFunctionIfStepping(edi, no_reg, dummy, dummy);
+  __ CheckDebugHook(edi, no_reg, dummy, dummy);
 
   // Load context from the function.
   __ mov(esi, FieldOperand(edi, JSFunction::kContextOffset));

src/x87/macro-assembler-x87.cc

@@ -1879,16 +1879,14 @@ void MacroAssembler::InvokePrologue(const ParameterCount& expected,
   }
 }
 
-
-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);
-  cmpb(Operand::StaticVariable(last_step_action), Immediate(StepIn));
-  j(less, &skip_flooding);
+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());
+  cmpb(Operand::StaticVariable(debug_hook_active), Immediate(0));
+  j(equal, &skip_hook);
   {
     FrameScope frame(this,
                      has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
@@ -1905,7 +1903,7 @@ void MacroAssembler::FloodFunctionIfStepping(Register fun, Register new_target,
     }
     Push(fun);
     Push(fun);
-    CallRuntime(Runtime::kDebugPrepareStepInIfStepping);
+    CallRuntime(Runtime::kDebugOnFunctionCall);
     Pop(fun);
     if (new_target.is_valid()) {
       Pop(new_target);
@@ -1919,7 +1917,7 @@ void MacroAssembler::FloodFunctionIfStepping(Register fun, Register new_target,
       SmiUntag(expected.reg());
     }
   }
-  bind(&skip_flooding);
+  bind(&skip_hook);
 }
 
 
@@ -1933,8 +1931,8 @@ void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
   DCHECK(function.is(edi));
   DCHECK_IMPLIES(new_target.is_valid(), new_target.is(edx));
 
-  if (call_wrapper.NeedsDebugStepCheck()) {
-    FloodFunctionIfStepping(function, new_target, expected, actual);
+  if (call_wrapper.NeedsDebugHookCheck()) {
+    CheckDebugHook(function, new_target, expected, actual);
   }
 
   // Clear the new.target register if not given.

src/x87/macro-assembler-x87.h

@@ -332,9 +332,10 @@ class MacroAssembler: public Assembler {
                           const ParameterCount& actual, InvokeFlag flag,
                           const CallWrapper& call_wrapper);
 
-  void FloodFunctionIfStepping(Register fun, Register new_target,
-                               const ParameterCount& expected,
-                               const ParameterCount& actual);
+  // On function call, call into the debugger if necessary.
+  void CheckDebugHook(Register fun, Register new_target,
+                      const ParameterCount& expected,
+                      const ParameterCount& actual);
 
   // Invoke the JavaScript function in the given register. Changes the
   // current context to the context in the function before invoking.