[interpreter, debugger] abstraction for source position calculation.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index bdf9a6c0f301a91f8abde905d738e49d2dba7ac7..312815f5eab4c6b8c4c759f39bd404610fd9e49f 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -14282,6 +14282,15 @@ void Code::ClearInlineCaches(Code::Kind* kind) {
 }
 
 
+int AbstractCode::SourcePosition(int offset) {
+  if (IsBytecodeArray()) return GetBytecodeArray()->SourcePosition(offset);
+  DCHECK(IsCode());
+  Code* code = GetCode();
+  Address pc = code->instruction_start() + offset;
+  return code->SourcePosition(pc);

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

Nit, could you make SourcePosition take the offset here to behave like
BytevodeArray (a TODO for a later CL is fine if it's invasive).

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

Done.

+}
+
+
 void SharedFunctionInfo::ClearTypeFeedbackInfo() {
   feedback_vector()->ClearSlots(this);
 }
@@ -14974,6 +14983,12 @@ void Code::Disassemble(const char* name, std::ostream& os) {  // NOLINT
 #endif  // ENABLE_DISASSEMBLER
 
 
+int BytecodeArray::SourcePosition(int offset) {
+  // TODO(yangguo): implement this.
+  return 0;
+}
+
+
 void BytecodeArray::Disassemble(std::ostream& os) {
   os << "Parameter count " << parameter_count() << "\n";
   os << "Frame size " << frame_size() << "\n";
@@ -19026,22 +19041,22 @@ bool JSWeakCollection::Delete(Handle<JSWeakCollection> weak_collection,
 }
 
 
-// Check if there is a break point at this code position.
-bool DebugInfo::HasBreakPoint(int code_position) {
-  // Get the break point info object for this code position.
-  Object* break_point_info = GetBreakPointInfo(code_position);
+// Check if there is a break point at this code offset.
+bool DebugInfo::HasBreakPoint(int code_offset) {
+  // Get the break point info object for this code offset.
+  Object* break_point_info = GetBreakPointInfo(code_offset);
 
   // If there is no break point info object or no break points in the break
-  // point info object there is no break point at this code position.
+  // point info object there is no break point at this code offset.
   if (break_point_info->IsUndefined()) return false;
   return BreakPointInfo::cast(break_point_info)->GetBreakPointCount() > 0;
 }
 
 
-// Get the break point info object for this code position.
-Object* DebugInfo::GetBreakPointInfo(int code_position) {
-  // Find the index of the break point info object for this code position.
-  int index = GetBreakPointInfoIndex(code_position);
+// Get the break point info object for this code offset.
+Object* DebugInfo::GetBreakPointInfo(int code_offset) {
+  // Find the index of the break point info object for this code offset.
+  int index = GetBreakPointInfoIndex(code_offset);
 
   // Return the break point info object if any.
   if (index == kNoBreakPointInfo) return GetHeap()->undefined_value();
@@ -19049,11 +19064,10 @@ Object* DebugInfo::GetBreakPointInfo(int code_position) {
 }
 
 
-// Clear a break point at the specified code position.
-void DebugInfo::ClearBreakPoint(Handle<DebugInfo> debug_info,
-                                int code_position,
+// Clear a break point at the specified code offset.
+void DebugInfo::ClearBreakPoint(Handle<DebugInfo> debug_info, int code_offset,
                                 Handle<Object> break_point_object) {
-  Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_position),
+  Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_offset),
                                   debug_info->GetIsolate());
   if (break_point_info->IsUndefined()) return;
   BreakPointInfo::ClearBreakPoint(
@@ -19062,13 +19076,11 @@ void DebugInfo::ClearBreakPoint(Handle<DebugInfo> debug_info,
 }
 
 
-void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info,
-                              int code_position,
-                              int source_position,
-                              int statement_position,
+void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info, int code_offset,
+                              int source_position, int statement_position,
                               Handle<Object> break_point_object) {
   Isolate* isolate = debug_info->GetIsolate();
-  Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_position),
+  Handle<Object> break_point_info(debug_info->GetBreakPointInfo(code_offset),
                                   isolate);
   if (!break_point_info->IsUndefined()) {
     BreakPointInfo::SetBreakPoint(
@@ -19077,7 +19089,7 @@ void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info,
     return;
   }
 
-  // Adding a new break point for a code position which did not have any
+  // Adding a new break point for a code offset which did not have any
   // break points before. Try to find a free slot.
   int index = kNoBreakPointInfo;
   for (int i = 0; i < debug_info->break_points()->length(); i++) {
@@ -19106,7 +19118,7 @@ void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info,
   // Allocate new BreakPointInfo object and set the break point.
   Handle<BreakPointInfo> new_break_point_info = Handle<BreakPointInfo>::cast(
       isolate->factory()->NewStruct(BREAK_POINT_INFO_TYPE));
-  new_break_point_info->set_code_position(code_position);
+  new_break_point_info->set_code_offset(code_offset);
   new_break_point_info->set_source_position(source_position);
   new_break_point_info->set_statement_position(statement_position);
   new_break_point_info->set_break_point_objects(
@@ -19116,9 +19128,9 @@ void DebugInfo::SetBreakPoint(Handle<DebugInfo> debug_info,
 }
 
 
-// Get the break point objects for a code position.
-Handle<Object> DebugInfo::GetBreakPointObjects(int code_position) {
-  Object* break_point_info = GetBreakPointInfo(code_position);
+// Get the break point objects for a code offset.
+Handle<Object> DebugInfo::GetBreakPointObjects(int code_offset) {
+  Object* break_point_info = GetBreakPointInfo(code_offset);
   if (break_point_info->IsUndefined()) {
     return GetIsolate()->factory()->undefined_value();
   }
@@ -19164,13 +19176,13 @@ Handle<Object> DebugInfo::FindBreakPointInfo(
 
 // Find the index of the break point info object for the specified code
 // position.
-int DebugInfo::GetBreakPointInfoIndex(int code_position) {
+int DebugInfo::GetBreakPointInfoIndex(int code_offset) {
   if (break_points()->IsUndefined()) return kNoBreakPointInfo;
   for (int i = 0; i < break_points()->length(); i++) {
     if (!break_points()->get(i)->IsUndefined()) {
       BreakPointInfo* break_point_info =
           BreakPointInfo::cast(break_points()->get(i));
-      if (break_point_info->code_position() == code_position) {
+      if (break_point_info->code_offset() == code_offset) {
         return i;
       }
     }