Support use of external strings as inputs to LoadCodeUnitsInstr.

runtime/vm/regexp_assembler.h

 // Copyright (c) 2014, 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_REGEXP_ASSEMBLER_H_
 #define VM_REGEXP_ASSEMBLER_H_
 
 #include "vm/assembler.h"
 #include "vm/intermediate_language.h"
 #include "vm/object.h"
@@ skipping 451 matching lines @@
 
   PushArgumentInstr* PushArgument(Value* value);
   PushArgumentInstr* PushLocal(LocalVariable* local);
 
   // Load a number of characters at the given offset from the
   // current position, into the current-character register.
   void LoadCurrentCharacterUnchecked(intptr_t cp_offset,
                                      intptr_t character_count);
 
   // Returns the character within the passed string at the specified index.
-  Value* CharacterAt(Definition* index);
+  Value* CharacterAt(LocalVariable* index);
 
   // Load a number of characters starting from index in the pattern string.
-  Value* LoadCodeUnitsAt(Value* pattern,
-                         Value* index,
-                         intptr_t character_count);
+  Value* LoadCodeUnitsAt(LocalVariable* index, intptr_t character_count);
 
   // Check whether preemption has been requested.
   void CheckPreemption();
 
   // Byte size of chars in the string to match (decided by the Mode argument)
   inline intptr_t char_size() { return static_cast<int>(mode_); }
 
   // Equivalent to a conditional branch to the label, unless the label
   // is NULL, in which case it is a conditional Backtrack.
   void BranchOrBacktrack(ComparisonInstr* comparison,
@@ skipping 111 matching lines @@
   // The start index within the string, passed as a function parameter.
   LocalVariable* start_index_param_;
 
   // An assortment of utility variables.
   LocalVariable* capture_length_;
   LocalVariable* match_start_index_;
   LocalVariable* capture_start_index_;
   LocalVariable* match_end_index_;
   LocalVariable* char_in_capture_;
   LocalVariable* char_in_match_;
+  LocalVariable* index_temp_;
 
   LocalVariable* result_;
 
   // Stored positions containing group bounds. Generated as needed.
   const intptr_t position_registers_count_;
   GrowableArray<LocalVariable*> position_registers_;
 
   // The actual array object used as the stack.
   GrowableObjectArray& stack_array_;
 
   IdAllocator block_id_;
   IdAllocator temp_id_;
   IdAllocator arg_id_;
   IdAllocator local_id_;
   IdAllocator indirect_id_;
 };
 
 
 }  // namespace dart
 
 #endif  // VM_REGEXP_ASSEMBLER_H_