VM: Optimized code for all of [External]{One|Two}ByteString::codeUnitAt.

runtime/vm/constant_propagator.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/constant_propagator.h"
 
 #include "vm/bit_vector.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/flow_graph_range_analysis.h"
@@ skipping 586 matching lines @@
 void ConstantPropagator::VisitNativeCall(NativeCallInstr* instr) {
   SetValue(instr, non_constant_);
 }
 
 
 void ConstantPropagator::VisitDebugStepCheck(DebugStepCheckInstr* instr) {
   // Nothing to do.
 }
 
 
-void ConstantPropagator::VisitStringFromCharCode(
-    StringFromCharCodeInstr* instr) {
+void ConstantPropagator::VisitOneByteStringFromCharCode(
+    OneByteStringFromCharCodeInstr* instr) {
   const Object& o = instr->char_code()->definition()->constant_value();
   if (o.IsNull() || IsNonConstant(o)) {
     SetValue(instr, non_constant_);
   } else if (IsConstant(o)) {
     const intptr_t ch_code = Smi::Cast(o).Value();
     ASSERT(ch_code >= 0);
     if (ch_code < Symbols::kMaxOneCharCodeSymbol) {
       RawString** table = Symbols::PredefinedAddress();
       SetValue(instr, String::ZoneHandle(Z, table[ch_code]));
     } else {
@@ skipping 1061 matching lines @@
   graph_->MergeBlocks();
   GrowableArray<BitVector*> dominance_frontier;
   graph_->ComputeDominators(&dominance_frontier);
 
   if (FLAG_trace_constant_propagation) {
     FlowGraphPrinter::PrintGraph("After CP", graph_);
   }
 }
 
 }  // namespace dart