Integrate the Irregexp Regular Expression Engine.

runtime/vm/flow_graph_range_analysis.cc

Index: runtime/vm/flow_graph_range_analysis.cc
diff --git a/runtime/vm/flow_graph_range_analysis.cc b/runtime/vm/flow_graph_range_analysis.cc
index 18487cc1281ab6d58b98657ca775564cef059c68..cf7c104fbc10257a022ca583b2b14cf63a8af15e 100644
--- a/runtime/vm/flow_graph_range_analysis.cc
+++ b/runtime/vm/flow_graph_range_analysis.cc
@@ -2825,6 +2825,22 @@ void LoadIndexedInstr::InferRange(RangeAnalysis* analysis, Range* range) {
 }
 
 
+void LoadCodeUnitsInstr::InferRange(RangeAnalysis* analysis, Range* range) {
+  ASSERT(class_id() == kOneByteStringCid ||
+         class_id() == kTwoByteStringCid);
+  switch (class_id()) {
+    case kOneByteStringCid:
+    case kTwoByteStringCid:
+      *range = Range(RangeBoundary::FromConstant(0),
+                     RangeBoundary::FromConstant(kMaxUint32));

[Ivan Posva, 2014/11/10 08:16:23]

Would we ever be loading 8 bytes at a time on 64-bit architectures?

[zerny-google, 2014/11/10 09:10:42]

No. The current LoadCodeUnitsInstr will pack at most 4 bytes (4x8 or 2x16)
regardless of architecture.

+      break;
+    default:
+      UNREACHABLE();
+      break;
+  }
+}
+
+
 void IfThenElseInstr::InferRange(RangeAnalysis* analysis, Range* range) {
   const intptr_t min = Utils::Minimum(if_true_, if_false_);
   const intptr_t max = Utils::Maximum(if_true_, if_false_);