VM: Fix bugs with missing deoptimization environment and int32x4 constructor

runtime/vm/intermediate_language.cc

Index: runtime/vm/intermediate_language.cc
diff --git a/runtime/vm/intermediate_language.cc b/runtime/vm/intermediate_language.cc
index 47e7dab5dd17252dab67b347c45110feb3f8fa34..e83f583bed0cf1dd57738d113bc0cafd450d938c 100644
--- a/runtime/vm/intermediate_language.cc
+++ b/runtime/vm/intermediate_language.cc
@@ -1257,6 +1257,22 @@ bool UnboxInt32Instr::CanDeoptimize() const {
 }
 
 
+bool UnboxUint32Instr::CanDeoptimize() const {
+  ASSERT(is_truncating());
+  if ((value()->Type()->ToCid() == kSmiCid) ||
+      (value()->Type()->ToCid() == kMintCid)) {
+    return false;
+  }
+  // Check input value's range.
+  Range* value_range = value()->definition()->range();
+  if (value_range != NULL &&

[Vyacheslav Egorov (Google), 2015/05/27 16:17:35]

no need for != NULL check. Fits does it for you (it calls IsUnknown which checks
for NULL)

you can just

return !RangeUtils::Fits(..., RangeBoundary::kRangeBoundaryInt64)

On the other hand RangeUtils::Fits(range, RangeBoundary::kRangeBoundaryInt64) is
equivalent to !Range::IsUnknown(range) because we never assign infinity ranges
to instructions, we only use them during range calculations. 

[Florian Schneider, 2015/05/28 08:11:09]

Done.

+      RangeUtils::Fits(value_range, RangeBoundary::kRangeBoundaryInt64)) {
+    return false;
+  }
+  return true;
+}
+
+
 bool BinaryInt32OpInstr::CanDeoptimize() const {
   switch (op_kind()) {
     case Token::kBIT_AND: