CpuProfiler: replace raw position with SourcePosition for DeoptReason

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index f4299ed7170936fd0b2bb11da07c41840155effd..86d4b11aeb5d113d5f1adce63e07f341a183de6a 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -465,7 +465,7 @@ void RelocInfoWriter::Write(const RelocInfo* rinfo) {
     DCHECK(begin_pos - pos_ <= RelocInfo::kMaxCallSize);
   } else if (rmode == RelocInfo::CODE_TARGET_WITH_ID) {
     // Use signed delta-encoding for id.
-    DCHECK(static_cast<int>(rinfo->data()) == rinfo->data());
+    DCHECK_EQ(static_cast<int>(rinfo->data()), rinfo->data());
     int id_delta = static_cast<int>(rinfo->data()) - last_id_;
     // Check if delta is small enough to fit in a tagged byte.
     if (is_intn(id_delta, kSmallDataBits)) {
@@ -483,12 +483,12 @@ void RelocInfoWriter::Write(const RelocInfo* rinfo) {
     WriteTaggedData(rinfo->data(), kDeoptReasonTag);
   } else if (RelocInfo::IsPosition(rmode)) {
     // Use signed delta-encoding for position.
-    DCHECK(static_cast<int>(rinfo->data()) == rinfo->data());
+    DCHECK_EQ(static_cast<int>(rinfo->data()), rinfo->data());
     int pos_delta = static_cast<int>(rinfo->data()) - last_position_;
     if (rmode == RelocInfo::STATEMENT_POSITION) {
       WritePosition(pc_delta, pos_delta, rmode);
     } else {
-      DCHECK(rmode == RelocInfo::POSITION);
+      DCHECK_EQ(rmode, RelocInfo::POSITION);
       if (pc_delta != 0 || last_mode_ != RelocInfo::POSITION) {
         FlushPosition();
         next_position_candidate_pc_delta_ = pc_delta;
@@ -1656,9 +1656,11 @@ bool PositionsRecorder::WriteRecordedPositions() {
 // Platform specific but identical code for all the platforms.
 
 
-void Assembler::RecordDeoptReason(const int reason, const int raw_position) {
+void Assembler::RecordDeoptReason(const int reason,
+                                  const SourcePosition position) {
   if (FLAG_trace_deopt || isolate()->cpu_profiler()->is_profiling()) {
     EnsureSpace ensure_space(this);
+    int raw_position = position.IsUnknown() ? 0 : position.raw();

[yurys, 2015/02/27 10:35:24]

Can we change SourcePosition so that raw() value of SourcePosition::Unknown() is
0 and avoid this code? Otherwise we rely on the fact that position.raw() cannot
return 0 which is non-obvious.

[loislo, 2015/02/27 12:04:28]

We use RelocInfo::kNoPosition in many other places, so it'd be non-trivial to
fix. I'd rather do this in another patch.

     RecordRelocInfo(RelocInfo::POSITION, raw_position);
     RecordRelocInfo(RelocInfo::DEOPT_REASON, reason);
   }