[interpreter, debugger] abstraction for source position calculation.

src/frames.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.
 
 #include "src/frames.h"
 
 #include <sstream>
 
 #include "src/ast/ast.h"
 #include "src/ast/scopeinfo.h"
@@ skipping 779 matching lines @@
 
 void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) const {
   DCHECK(functions->length() == 0);
   functions->Add(function());
 }
 
 
 void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
   DCHECK(functions->length() == 0);
   Code* code_pointer = LookupCode();
-  int offset = static_cast<int>(pc() - code_pointer->address());
+  int offset = static_cast<int>(pc() - code_pointer->instruction_start());
   FrameSummary summary(receiver(),
                        function(),
                        code_pointer,
                        offset,
                        IsConstructor());
   functions->Add(summary);
 }
 
 
 int JavaScriptFrame::LookupExceptionHandlerInTable(
@@ skipping 79 matching lines @@
 void JavaScriptFrame::RestoreOperandStack(FixedArray* store) {
   int operands_count = store->length();
   DCHECK_LE(operands_count, ComputeOperandsCount());
   for (int i = 0; i < operands_count; i++) {
     DCHECK_EQ(GetOperand(i), isolate()->heap()->the_hole_value());
     Memory::Object_at(GetOperandSlot(i)) = store->get(i);
   }
 }
 
 
-FrameSummary::FrameSummary(Object* receiver, JSFunction* function, Code* code,
-                           int offset, bool is_constructor)
+FrameSummary::FrameSummary(Object* receiver, JSFunction* function,
+                           HeapObject* abstract_code, int code_offset,

[rmcilroy, 2016/01/22 19:16:34]

Is there a reason this can't be AbstractCode type.

[Yang, 2016/01/28 09:09:53]

It can be. But then the caller would have to do the casting. Done.

+                           bool is_constructor)
     : receiver_(receiver, function->GetIsolate()),
       function_(function),
-      code_(code),
-      offset_(offset),
+      abstract_code_(AbstractCode::cast(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_);
 }
 
 
 void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
   DCHECK(frames->length() == 0);
   DCHECK(is_optimized());
 
   // Delegate to JS frame in absence of turbofan deoptimization.
   // TODO(turbofan): Revisit once we support deoptimization across the board.
   if (LookupCode()->is_turbofanned() && function()->shared()->asm_function() &&
@@ skipping 58 matching lines @@
       } else {
         // The receiver is not in a stack slot nor in a literal.  We give up.
         it.Skip(Translation::NumberOfOperandsFor(opcode));
         // TODO(3029): Materializing a captured object (or duplicated
         // object) is hard, we return undefined for now. This breaks the
         // produced stack trace, as constructor frames aren't marked as
         // such anymore.
         receiver = isolate()->heap()->undefined_value();
       }
 
-      Code* const code = shared_info->code();
+      AbstractCode* abstract_code = shared_info->AbstractCode();
 
-      unsigned pc_offset;
+      int code_offset;

[rmcilroy, 2016/01/22 19:16:34]

Could this still be unsigned? It should never be negative right?

[Yang, 2016/01/28 09:09:53]

Done.

       if (frame_opcode == Translation::JS_FRAME) {
+        Code* code = abstract_code->GetCode();
         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);
+        DCHECK_LE(0, code_offset);
       } 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;

[rmcilroy, 2016/01/22 19:16:34]

Could this use GetBytecodeOffset now?

[Yang, 2016/01/28 09:09:53]

No. The frame object is still an OptimizedFrame. The translation does not offer
a bytecode offset from what I can see.

       }
-      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) {
       // The next encountered JS_FRAME will be marked as a constructor call.
       it.Skip(Translation::NumberOfOperandsFor(frame_opcode));
       DCHECK(!is_constructor);
       is_constructor = true;
     } else {
       // Skip over operands to advance to the next opcode.
       it.Skip(Translation::NumberOfOperandsFor(frame_opcode));
@@ skipping 123 matching lines @@
 
 void InterpretedFrame::PatchBytecodeOffset(int new_offset) {
   const int index = InterpreterFrameConstants::kBytecodeOffsetExpressionIndex;
   DCHECK_EQ(InterpreterFrameConstants::kBytecodeOffsetFromFp,
             StandardFrameConstants::kExpressionsOffset - index * kPointerSize);
   int raw_offset = new_offset + BytecodeArray::kHeaderSize - kHeapObjectTag;
   SetExpression(index, Smi::FromInt(raw_offset));
 }
 
 
+void InterpretedFrame::Summarize(List<FrameSummary>* functions) {
+  DCHECK(functions->length() == 0);
+  DCHECK_EQ(
+      isolate()->builtins()->builtin(Builtins::kInterpreterEntryTrampoline),
+      LookupCode());
+  FrameSummary summary(receiver(), function(),
+                       function()->shared()->bytecode_array(),
+                       GetBytecodeOffset(), IsConstructor());
+  functions->Add(summary);
+}
+
+
 int ArgumentsAdaptorFrame::GetNumberOfIncomingArguments() const {
   return Smi::cast(GetExpression(0))->value();
 }
 
 
 Address ArgumentsAdaptorFrame::GetCallerStackPointer() const {
   return fp() + StandardFrameConstants::kCallerSPOffset;
 }
 
 
@@ skipping 448 matching lines @@
   for (StackFrameIterator it(isolate); !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
     list.Add(frame, zone);
   }
   return list.ToVector();
 }
 
 
 }  // namespace internal
 }  // namespace v8