Fix a bug in SSA renaming introduced when using the RemoveFromGraph helper for removing instruction…

vm/intermediate_language.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/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
@@ skipping 514 matching lines @@
          successor()->IsBlockEntry());
   return successor() != NULL ? 1 : 0;
 }
 
 
 BlockEntryInstr* Instruction::SuccessorAt(intptr_t index) const {
   return successor()->AsBlockEntry();
 }
 
 
-void Instruction::RemoveFromGraph() {
+Instruction* Instruction::RemoveFromGraph() {
   ASSERT(!IsBlockEntry());
   ASSERT(!IsBranch());
   ASSERT(!IsThrow());
   ASSERT(!IsReturn());
   ASSERT(!IsReThrow());
   ASSERT(previous() != NULL);
   Instruction* next = successor();
   previous()->set_successor(next);
   if (next != NULL) {
     if (!next->IsBlockEntry()) {
       next->set_previous(previous());
     } else {
       // Removing the last instruction of a block.
       // Update last_instruction of the current basic block.
       Instruction* current = this;
       while (!current->IsBlockEntry()) {
         current = current->previous();
       }
       ASSERT(current->AsBlockEntry()->last_instruction() == this);
       current->AsBlockEntry()->set_last_instruction(previous());
     }
   }
   // Reset successor and previous instruction to indicate
   // that the instruction is removed from the graph.
   set_successor(NULL);
   set_previous(NULL);
+  return next;
 }
 
 
 intptr_t GraphEntryInstr::SuccessorCount() const {
   return 1 + catch_entries_.length();
 }
 
 
 BlockEntryInstr* GraphEntryInstr::SuccessorAt(intptr_t index) const {
   if (index == 0) return normal_entry_;
@@ skipping 764 matching lines @@
   const ExternalLabel label(closure_function.ToCString(), stub.EntryPoint());
   compiler->GenerateCall(token_pos(), try_index(), &label,
                          PcDescriptors::kOther);
   __ Drop(2);  // Discard type arguments and receiver.
 }
 
 
 #undef __
 
 }  // namespace dart