Merge RawICData::range_feedback_ field into RawICData::state_bits_.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index facb353a658d6d886661463081d5558a84260587..d6cf78eb81f1a3ed9e36c8606ac0b3ee80b72175 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -11434,12 +11434,15 @@ void ICData::SetDeoptReasons(uint32_t reasons) const {
 
 
 bool ICData::HasDeoptReason(DeoptReasonId reason) const {
+  ASSERT(reason <= kLastRecordedDeoptReason);
   return (DeoptReasons() & (1 << reason)) != 0;
 }
 
 
 void ICData::AddDeoptReason(DeoptReasonId reason) const {
-  SetDeoptReasons(DeoptReasons() | (1 << reason));
+  if (reason <= kLastRecordedDeoptReason) {

[zra, 2014/12/15 20:57:38]

Why is this not an assert?

[Vyacheslav Egorov (Google), 2014/12/15 21:02:21]

Caller (deoptimizer) can try to add deopt reason which we don't care about -
this is fine, we just drop it to the floor.

On the other hand if optimizer is checking (via HasDeoptReason) for a deopt
reason, which we don't record, then this is a bug. Because reason has to be
recordable for HasDeoptReason to make sense.

That's why this is guarded with an if and the other one is an assert.

Alternatively I could move this *if* to the caller (deoptimizer), but that felt
like a wrong place.

WDYT? 

[zra, 2014/12/15 21:04:58]

Makes sense. I think it's fine as-is. Thanks!

+    SetDeoptReasons(DeoptReasons() | (1 << reason));
+  }
 }
 
 
@@ -11472,11 +11475,6 @@ bool ICData::MayCheckForJSWarning() const {
 }
 
 
-void ICData::set_range_feedback(uint32_t feedback) {
-  StoreNonPointer(&raw_ptr()->range_feedback_, feedback);
-}
-
-
 void ICData::set_state_bits(uint32_t bits) const {
   StoreNonPointer(&raw_ptr()->state_bits_, bits);
 }
@@ -11932,7 +11930,6 @@ RawICData* ICData::New(const Function& owner,
   result.set_arguments_descriptor(arguments_descriptor);
   result.set_deopt_id(deopt_id);
   result.set_state_bits(0);
-  result.set_range_feedback(0);
   result.SetNumArgsTested(num_args_tested);
   // Number of array elements in one test entry.
   intptr_t len = result.TestEntryLength();
@@ -12013,8 +12010,10 @@ bool ICData::HasRangeFeedback() const {
 
 ICData::RangeFeedback ICData::DecodeRangeFeedbackAt(intptr_t idx) const {
   ASSERT((0 <= idx) && (idx < 3));
+  const uint32_t raw_feedback =
+      RangeFeedbackBits::decode(raw_ptr()->state_bits_);
   const uint32_t feedback =
-      (range_feedback() >> (idx * kBitsPerRangeFeedback)) & kRangeFeedbackMask;
+      (raw_feedback >> (idx * kBitsPerRangeFeedback)) & kRangeFeedbackMask;
   if ((feedback & kInt64RangeBit) != 0) {
     return kInt64Range;
   }