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

runtime/vm/intermediate_language.h

 // 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.
 
 #ifndef VM_INTERMEDIATE_LANGUAGE_H_
 #define VM_INTERMEDIATE_LANGUAGE_H_
 
 #include "vm/allocation.h"
 #include "vm/ast.h"
 #include "vm/growable_array.h"
@@ skipping 496 matching lines @@
   M(Unbox)                                                                     \
   M(BoxInt64)                                                                  \
   M(UnboxInt64)                                                                \
   M(CaseInsensitiveCompareUC16)                                                \
   M(BinaryMintOp)                                                              \
   M(ShiftMintOp)                                                               \
   M(UnaryMintOp)                                                               \
   M(CheckArrayBound)                                                           \
   M(Constraint)                                                                \
   M(StringToCharCode)                                                          \
-  M(StringFromCharCode)                                                        \
+  M(OneByteStringFromCharCode)                                                 \
   M(StringInterpolate)                                                         \
   M(InvokeMathCFunction)                                                       \
   M(MergedMath)                                                                \
   M(GuardFieldClass)                                                           \
   M(GuardFieldLength)                                                          \
   M(IfThenElse)                                                                \
   M(BinaryFloat32x4Op)                                                         \
   M(Simd32x4Shuffle)                                                           \
   M(Simd32x4ShuffleMix)                                                        \
   M(Simd32x4GetSignMask)                                                       \
@@ skipping 3394 matching lines @@
  private:
   const intptr_t class_id_;
   const TokenPosition token_pos_;
   const intptr_t element_count_;
   Representation representation_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadCodeUnitsInstr);
 };
 
 
-class StringFromCharCodeInstr : public TemplateDefinition<1, NoThrow, Pure> {
+class OneByteStringFromCharCodeInstr
+    : public TemplateDefinition<1, NoThrow, Pure> {
  public:
-  StringFromCharCodeInstr(Value* char_code, intptr_t cid) : cid_(cid) {
-    ASSERT(char_code != NULL);
-    ASSERT(char_code->definition()->IsLoadIndexed());
-    ASSERT(char_code->definition()->AsLoadIndexed()->class_id() ==
-           kOneByteStringCid);
+  explicit OneByteStringFromCharCodeInstr(Value* char_code) {
     SetInputAt(0, char_code);
   }
 
-  DECLARE_INSTRUCTION(StringFromCharCode)
+  DECLARE_INSTRUCTION(OneByteStringFromCharCode)
   virtual CompileType ComputeType() const;
 
   Value* char_code() const { return inputs_[0]; }
 
   virtual bool CanDeoptimize() const { return false; }
 
   virtual bool AttributesEqual(Instruction* other) const {
-    return other->AsStringFromCharCode()->cid_ == cid_;
+    return true;
   }
 
  private:
-  const intptr_t cid_;
-
-  DISALLOW_COPY_AND_ASSIGN(StringFromCharCodeInstr);
+  DISALLOW_COPY_AND_ASSIGN(OneByteStringFromCharCodeInstr);
 };
 
 
 class StringToCharCodeInstr : public TemplateDefinition<1, NoThrow, Pure> {
  public:
   StringToCharCodeInstr(Value* str, intptr_t cid) : cid_(cid) {
     ASSERT(str != NULL);
     SetInputAt(0, str);
   }
 
@@ skipping 4293 matching lines @@
   LocationSummary* Name::MakeLocationSummary(Zone* zone, bool opt) const {    \
     UNIMPLEMENTED();                                                          \
     return NULL;                                                              \
   }                                                                           \
   void Name::EmitNativeCode(FlowGraphCompiler* compiler) { UNIMPLEMENTED(); }
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_