Remove StringCharCodeAtInstr and handle it as part of LoadIndexed.

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2012, 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/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
@@ skipping 1202 matching lines @@
       }
       InlineStringIsEmptyGetter(call);
       return true;
     default:
       ASSERT(recognized_kind == MethodRecognizer::kUnknown);
   }
   return false;
 }
 
 
-StringCharCodeAtInstr* FlowGraphOptimizer::BuildStringCharCodeAt(
+LoadIndexedInstr* FlowGraphOptimizer::BuildStringCharCodeAt(
     InstanceCallInstr* call,
     intptr_t cid) {
   Value* str = call->ArgumentAt(0)->value();
   Value* index = call->ArgumentAt(1)->value();
   AddCheckClass(call, str->Copy());
   InsertBefore(call,
                new CheckSmiInstr(index->Copy(), call->deopt_id()),
                call->env(),
                Definition::kEffect);
   // If both index and string are constants, then do a compile-time check.
@@ skipping 12 matching lines @@
   if (!skip_check) {
     // Insert bounds check.
     InsertBefore(call,
                  new CheckArrayBoundInstr(str->Copy(),
                                           index->Copy(),
                                           cid,
                                           call),
                  call->env(),
                  Definition::kEffect);
   }
-  return new StringCharCodeAtInstr(str, index, cid);
+  return new LoadIndexedInstr(str, index, cid);
 }
 
 
 // Inline only simple, frequently called core library methods.
 bool FlowGraphOptimizer::TryInlineInstanceMethod(InstanceCallInstr* call) {
   ASSERT(call->HasICData());
   const ICData& ic_data = *call->ic_data();
   if ((ic_data.NumberOfChecks() == 0) || !ic_data.HasOneTarget()) {
     // No type feedback collected or multiple targets found.
     return false;
   }
   Function& target = Function::Handle();
   GrowableArray<intptr_t> class_ids;
   ic_data.GetCheckAt(0, &class_ids, &target);
   MethodRecognizer::Kind recognized_kind =
       MethodRecognizer::RecognizeKind(target);
   if ((recognized_kind == MethodRecognizer::kStringBaseCharCodeAt) &&
       (ic_data.NumberOfChecks() == 1) &&
       ((class_ids[0] == kOneByteStringCid) ||
        (class_ids[0] == kTwoByteStringCid))) {
-    StringCharCodeAtInstr* instr = BuildStringCharCodeAt(call, class_ids[0]);
+    LoadIndexedInstr* instr = BuildStringCharCodeAt(call, class_ids[0]);
     call->ReplaceWith(instr, current_iterator());
     RemovePushArguments(call);
     return true;
   }
   if ((recognized_kind == MethodRecognizer::kStringBaseCharAt) &&
       (ic_data.NumberOfChecks() == 1) &&
       (class_ids[0] == kOneByteStringCid)) {
     // TODO(fschneider): Handle TwoByteString.
-    StringCharCodeAtInstr* load_char_code =
+    LoadIndexedInstr* load_char_code =
         BuildStringCharCodeAt(call, class_ids[0]);
     InsertBefore(call, load_char_code, NULL, Definition::kValue);
     StringFromCharCodeInstr* char_at =
         new StringFromCharCodeInstr(new Value(load_char_code),
                                     kOneByteStringCid);
     call->ReplaceWith(char_at, current_iterator());
     RemovePushArguments(call);
     return true;
   }
 
@@ skipping 2732 matching lines @@
     }
   }
 }
 
 
 void ConstantPropagator::VisitNativeCall(NativeCallInstr* instr) {
   SetValue(instr, non_constant_);
 }
 
 
-void ConstantPropagator::VisitStringCharCodeAt(StringCharCodeAtInstr* instr) {
-  SetValue(instr, non_constant_);
-}
-
-
 void ConstantPropagator::VisitStringFromCharCode(
     StringFromCharCodeInstr* instr) {
   SetValue(instr, non_constant_);
 }
 
 
 void ConstantPropagator::VisitLoadIndexed(LoadIndexedInstr* instr) {
   SetValue(instr, non_constant_);
 }
 
@@ skipping 465 matching lines @@
 
   if (FLAG_trace_constant_propagation) {
     OS::Print("\n==== After constant propagation ====\n");
     FlowGraphPrinter printer(*graph_);
     printer.PrintBlocks();
   }
 }
 
 
 }  // namespace dart