Improve positions recording for calls.

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index ce90dceacbc9f8b0e3651efd5fb4f18f50cc6d24..7493673e8191f68e74fcbb6b465591897d832b3b 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -804,4 +804,53 @@ ExternalReference ExternalReference::debug_step_in_fp_address() {
 }
 #endif
 
+
+void PositionsRecorder::RecordPosition(int pos,
+                                       PositionRecordingType recording_type) {
+  ASSERT(pos != RelocInfo::kNoPosition);
+  ASSERT(pos >= 0);
+  current_position_ = pos;
+  current_position_recording_type_ = recording_type;
+}
+
+
+void PositionsRecorder::RecordStatementPosition(int pos) {
+  ASSERT(pos != RelocInfo::kNoPosition);
+  ASSERT(pos >= 0);
+  current_statement_position_ = pos;
+}
+
+
+bool PositionsRecorder::WriteRecordedPositions() {
+  bool written = false;
+
+  // Write the statement position if it is different from what was written last
+  // time.
+  if (current_statement_position_ != written_statement_position_) {
+    EnsureSpace ensure_space(assembler_);
+    assembler_->RecordRelocInfo(RelocInfo::STATEMENT_POSITION,
+                                current_statement_position_);
+    written_statement_position_ = current_statement_position_;
+    written = true;
+  }
+
+  // Write the position if it is different from what was written last time and
+  // also different from the written statement position or was forced.
+  if (current_position_ != written_position_ &&
+      (current_position_ != current_statement_position_ || !written) &&
+      (current_position_ != written_statement_position_
+       || current_position_recording_type_ == FORCED_POSITION)) {
+    EnsureSpace ensure_space(assembler_);
+    assembler_->RecordRelocInfo(RelocInfo::POSITION, current_position_);
+    written_position_ = current_position_;
+    written = true;
+  }
+
+  current_position_recording_type_ = NORMAL_POSITION;
+
+  // Return whether something was written.
+  return written;
+}
+
+
 } }  // namespace v8::internal