Prevent deopt when assigning double values to typed arrays

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index 3b01f5761227bdc393e7ad0a755192341f93b288..37582fdb3d8ad785ccc289d18e66eaf8ce2058e4 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -59,6 +59,8 @@ const char* Representation::Mnemonic() const {
     case kTagged: return "t";
     case kDouble: return "d";
     case kInteger32: return "i";
+    case kTruncatedInteger32: return "ti";
+    case kClampedRoundedUInteger8: return "cri";
     case kExternal: return "x";
     case kNumRepresentations:
       UNREACHABLE();
@@ -727,8 +729,6 @@ void HTypeofIs::PrintDataTo(StringStream* stream) {
 void HChange::PrintDataTo(StringStream* stream) {
   HUnaryOperation::PrintDataTo(stream);
   stream->Add(" %s to %s", from_.Mnemonic(), to().Mnemonic());
-
-  if (CanTruncateToInt32()) stream->Add(" truncating-int32");
   if (CheckFlag(kBailoutOnMinusZero)) stream->Add(" -0?");
 }
 
@@ -796,9 +796,11 @@ Range* HConstant::InferRange() {
 
 
 Range* HPhi::InferRange() {
-  if (representation().IsInteger32()) {
+  if (representation().IsInteger()) {
     if (block()->IsLoopHeader()) {
-      Range* range = new Range(kMinInt, kMaxInt);
+      Range* range = representation().IsClampedRoundedInteger8()
+          ? new Range(0, 255)
+          : new Range(kMinInt, kMaxInt);
       return range;
     } else {
       Range* range = OperandAt(0)->range()->Copy();
@@ -814,7 +816,7 @@ Range* HPhi::InferRange() {
 
 
 Range* HAdd::InferRange() {
-  if (representation().IsInteger32()) {
+  if (representation().IsInteger()) {
     Range* a = left()->range();
     Range* b = right()->range();
     Range* res = a->Copy();
@@ -831,7 +833,7 @@ Range* HAdd::InferRange() {
 
 
 Range* HSub::InferRange() {
-  if (representation().IsInteger32()) {
+  if (representation().IsInteger()) {
     Range* a = left()->range();
     Range* b = right()->range();
     Range* res = a->Copy();
@@ -847,7 +849,7 @@ Range* HSub::InferRange() {
 
 
 Range* HMul::InferRange() {
-  if (representation().IsInteger32()) {
+  if (representation().IsInteger()) {
     Range* a = left()->range();
     Range* b = right()->range();
     Range* res = a->Copy();
@@ -865,7 +867,7 @@ Range* HMul::InferRange() {
 
 
 Range* HDiv::InferRange() {
-  if (representation().IsInteger32()) {
+  if (representation().IsInteger()) {
     Range* result = new Range();
     if (left()->range()->CanBeMinusZero()) {
       result->set_can_be_minus_zero(true);
@@ -890,7 +892,7 @@ Range* HDiv::InferRange() {
 
 
 Range* HMod::InferRange() {
-  if (representation().IsInteger32()) {
+  if (representation().IsInteger()) {
     Range* a = left()->range();
     Range* result = new Range();
     if (a->CanBeMinusZero() || a->CanBeNegative()) {
@@ -1035,7 +1037,9 @@ HConstant::HConstant(Handle<Object> handle, Representation r)
 
 
 HConstant* HConstant::CopyToRepresentation(Representation r) const {
-  if (r.IsInteger32() && !has_int32_value_) return NULL;
+  if (r.IsInteger() && !has_int32_value_) return NULL;
+  if (r.IsClampedRoundedInteger8() &&
+      (int32_value_ > 255 || int32_value_ < 0)) return NULL;
   if (r.IsDouble() && !has_double_value_) return NULL;
   return new HConstant(handle_, r);
 }
@@ -1045,7 +1049,15 @@ HConstant* HConstant::CopyToTruncatedInt32() const {
   if (!has_double_value_) return NULL;
   int32_t truncated = NumberToInt32(*handle_);
   return new HConstant(FACTORY->NewNumberFromInt(truncated),
-                       Representation::Integer32());
+                       Representation::TruncatedInteger32());
+}
+
+
+HConstant* HConstant::CopyToClampedRoundedUInt8() const {
+  if (!has_double_value_) return NULL;
+  int32_t clamped_rounded = NumberToClampedUInt8(*handle_);
+  return new HConstant(FACTORY->NewNumberFromInt(clamped_rounded),
+                       Representation::ClampedRoundedUInteger8());
 }
 
 
@@ -1511,14 +1523,14 @@ HType HSar::CalculateInferredType() {
 HValue* HUnaryMathOperation::EnsureAndPropagateNotMinusZero(
     BitVector* visited) {
   visited->Add(id());
-  if (representation().IsInteger32() &&
-      !value()->representation().IsInteger32()) {
+  if (representation().IsInteger() &&
+      !value()->representation().IsInteger()) {
     if (value()->range() == NULL || value()->range()->CanBeMinusZero()) {
       SetFlag(kBailoutOnMinusZero);
     }
   }
-  if (RequiredInputRepresentation(0).IsInteger32() &&
-      representation().IsInteger32()) {
+  if (RequiredInputRepresentation(0).IsInteger() &&
+      representation().IsInteger()) {
     return value();
   }
   return NULL;
@@ -1528,12 +1540,14 @@ HValue* HUnaryMathOperation::EnsureAndPropagateNotMinusZero(
 
 HValue* HChange::EnsureAndPropagateNotMinusZero(BitVector* visited) {
   visited->Add(id());
-  if (from().IsInteger32()) return NULL;
-  if (CanTruncateToInt32()) return NULL;
+  if (from().IsInteger()) return NULL;
+  if (to().IsTruncatedInteger32() || to().IsClampedRoundedInteger8()) {
+    return NULL;
+  }
   if (value()->range() == NULL || value()->range()->CanBeMinusZero()) {
     SetFlag(kBailoutOnMinusZero);
   }
-  ASSERT(!from().IsInteger32() || !to().IsInteger32());
+  ASSERT(!from().IsInteger() || !to().IsInteger());
   return NULL;
 }