[interpreter, debugger] abstraction for source position calculation.

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index 1b503065245c981807dd8f160d2fd6e09dbc0493..4e499455f7eabb15295ba0c5f4e7e0bc19f5c900 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -801,12 +801,10 @@ void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) const {
 
 void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
   DCHECK(functions->length() == 0);
-  Code* code_pointer = LookupCode();
-  int offset = static_cast<int>(pc() - code_pointer->address());
-  FrameSummary summary(receiver(),
-                       function(),
-                       code_pointer,
-                       offset,
+  Code* code = LookupCode();
+  int offset = static_cast<int>(pc() - code->instruction_start());
+  AbstractCode* abstract_code = AbstractCode::cast(code);
+  FrameSummary summary(receiver(), function(), abstract_code, offset,
                        IsConstructor());
   functions->Add(summary);
 }
@@ -831,7 +829,7 @@ void JavaScriptFrame::PrintFunctionAndOffset(JSFunction* function, Code* code,
   PrintF(file, "+%d", code_offset);
   if (print_line_number) {
     SharedFunctionInfo* shared = function->shared();
-    int source_pos = code->SourcePosition(pc);
+    int source_pos = code->SourcePosition(code_offset);
     Object* maybe_script = shared->script();
     if (maybe_script->IsScript()) {
       Script* script = Script::cast(maybe_script);
@@ -901,26 +899,30 @@ void JavaScriptFrame::RestoreOperandStack(FixedArray* store) {
   }
 }
 
-
-FrameSummary::FrameSummary(Object* receiver, JSFunction* function, Code* code,
-                           int offset, bool is_constructor)
+FrameSummary::FrameSummary(Object* receiver, JSFunction* function,
+                           AbstractCode* abstract_code, int code_offset,
+                           bool is_constructor)
     : receiver_(receiver, function->GetIsolate()),
       function_(function),
-      code_(code),
-      offset_(offset),
+      abstract_code_(abstract_code),
+      code_offset_(code_offset),
       is_constructor_(is_constructor) {}
 
-
 void FrameSummary::Print() {
   PrintF("receiver: ");
   receiver_->ShortPrint();
   PrintF("\nfunction: ");
   function_->shared()->DebugName()->ShortPrint();
   PrintF("\ncode: ");
-  code_->ShortPrint();
-  if (code_->kind() == Code::FUNCTION) PrintF(" NON-OPT");
-  if (code_->kind() == Code::OPTIMIZED_FUNCTION) PrintF(" OPT");
-  PrintF("\npc: %d\n", offset_);
+  abstract_code_->ShortPrint();
+  if (abstract_code_->IsCode()) {
+    Code* code = abstract_code_->GetCode();
+    if (code->kind() == Code::FUNCTION) PrintF(" UNOPT ");
+    if (code->kind() == Code::OPTIMIZED_FUNCTION) PrintF(" OPT ");
+  } else {
+    PrintF(" BYTECODE ");
+  }
+  PrintF("\npc: %d\n", code_offset_);
 }
 
 
@@ -999,24 +1001,26 @@ void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
         receiver = isolate()->heap()->undefined_value();
       }
 
-      Code* const code = shared_info->code();
+      AbstractCode* abstract_code;
 
-      unsigned pc_offset;
+      unsigned code_offset;
       if (frame_opcode == Translation::JS_FRAME) {
+        Code* code = shared_info->code();
         DeoptimizationOutputData* const output_data =
             DeoptimizationOutputData::cast(code->deoptimization_data());
         unsigned const entry =
             Deoptimizer::GetOutputInfo(output_data, ast_id, shared_info);
-        pc_offset =
-            FullCodeGenerator::PcField::decode(entry) + Code::kHeaderSize;
-        DCHECK_NE(0U, pc_offset);
+        code_offset = FullCodeGenerator::PcField::decode(entry);
+        abstract_code = AbstractCode::cast(code);
       } else {
         // TODO(rmcilroy): Modify FrameSummary to enable us to summarize
         // based on the BytecodeArray and bytecode offset.
         DCHECK_EQ(frame_opcode, Translation::INTERPRETED_FRAME);
-        pc_offset = 0;
+        code_offset = 0;
+        abstract_code = AbstractCode::cast(shared_info->bytecode_array());
       }
-      FrameSummary summary(receiver, function, code, pc_offset, is_constructor);
+      FrameSummary summary(receiver, function, abstract_code, code_offset,
+                           is_constructor);
       frames->Add(summary);
       is_constructor = false;
     } else if (frame_opcode == Translation::CONSTRUCT_STUB_FRAME) {
@@ -1159,6 +1163,14 @@ void InterpretedFrame::PatchBytecodeOffset(int new_offset) {
   SetExpression(index, Smi::FromInt(raw_offset));
 }
 
+void InterpretedFrame::Summarize(List<FrameSummary>* functions) {
+  DCHECK(functions->length() == 0);
+  AbstractCode* abstract_code =
+      AbstractCode::cast(function()->shared()->bytecode_array());
+  FrameSummary summary(receiver(), function(), abstract_code,
+                       GetBytecodeOffset(), IsConstructor());
+  functions->Add(summary);
+}
 
 int ArgumentsAdaptorFrame::GetNumberOfIncomingArguments() const {
   return Smi::cast(GetExpression(0))->value();
@@ -1244,7 +1256,8 @@ void JavaScriptFrame::Print(StringStream* accumulator,
     Address pc = this->pc();
     if (code != NULL && code->kind() == Code::FUNCTION &&
         pc >= code->instruction_start() && pc < code->instruction_end()) {
-      int source_pos = code->SourcePosition(pc);
+      int offset = static_cast<int>(pc - code->instruction_start());
+      int source_pos = code->SourcePosition(offset);
       int line = script->GetLineNumber(source_pos) + 1;
       accumulator->Add(":%d", line);
     } else {