[debugger] introduce abstract interface for break location.

src/objects.cc

 // Copyright 2015 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/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <sstream>
 
@@ skipping 14480 matching lines @@
     if (target->is_inline_cache_stub()) {
       if (kind == NULL || *kind == target->kind()) {
         IC::Clear(this->GetIsolate(), info->pc(),
                   info->host()->constant_pool());
       }
     }
   }
 }
 
 int AbstractCode::SourcePosition(int offset) {
-  if (IsBytecodeArray()) return GetBytecodeArray()->SourcePosition(offset);
-  return GetCode()->SourcePosition(offset);
+  return IsBytecodeArray() ? GetBytecodeArray()->SourcePosition(offset)
+                           : GetCode()->SourcePosition(offset);
+}
+
+int AbstractCode::SourceStatementPosition(int offset) {
+  return IsBytecodeArray() ? GetBytecodeArray()->SourceStatementPosition(offset)
+                           : GetCode()->SourceStatementPosition(offset);
 }
 
 void SharedFunctionInfo::ClearTypeFeedbackInfo() {
   feedback_vector()->ClearSlots(this);
 }
 
 
 void SharedFunctionInfo::ClearTypeFeedbackInfoAtGCTime() {
   feedback_vector()->ClearSlotsAtGCTime(this);
 }
@@ skipping 674 matching lines @@
 
   os << "RelocInfo (size = " << relocation_size() << ")\n";
   for (RelocIterator it(this); !it.done(); it.next()) {
     it.rinfo()->Print(GetIsolate(), os);
   }
   os << "\n";
 }
 #endif  // ENABLE_DISASSEMBLER
 
 int BytecodeArray::SourcePosition(int offset) {
-  return interpreter::SourcePositionTableIterator::PositionFromBytecodeOffset(
-      this, offset);
+  int last_position = 0;
+  for (interpreter::SourcePositionTableIterator iterator(this);
+       !iterator.done() && iterator.bytecode_offset() <= offset;
+       iterator.Advance()) {
+    last_position = iterator.source_position();
+  }
+  return last_position;
+}
+
+int BytecodeArray::SourceStatementPosition(int offset) {
+  // First find the position as close as possible using all position
+  // information.
+  int position = SourcePosition(offset);
+  // Now find the closest statement position before the position.
+  int statement_position = 0;
+  interpreter::SourcePositionTableIterator iterator(this);
+  while (!iterator.done()) {
+    if (iterator.is_statement()) {
+      int p = iterator.source_position();
+      if (statement_position < p && p <= position) {
+        statement_position = p;
+      }
+    }
+    iterator.Advance();
+  }
+  return statement_position;
 }
 
 void BytecodeArray::Disassemble(std::ostream& os) {
   os << "Parameter count " << parameter_count() << "\n";
   os << "Frame size " << frame_size() << "\n";
   Vector<char> buf = Vector<char>::New(50);
 
   const uint8_t* first_bytecode_address = GetFirstBytecodeAddress();
   int bytecode_size = 0;
 
@@ skipping 4753 matching lines @@
   if (cell->value() != *new_value) {
     cell->set_value(*new_value);
     Isolate* isolate = cell->GetIsolate();
     cell->dependent_code()->DeoptimizeDependentCodeGroup(
         isolate, DependentCode::kPropertyCellChangedGroup);
   }
 }
 
 }  // namespace internal
 }  // namespace v8