Add support for fixed parameters in SSA builder and fix a bug in the pre-order graph traversal.

vm/intermediate_language.h

 // 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.
 
 #ifndef VM_INTERMEDIATE_LANGUAGE_H_
 #define VM_INTERMEDIATE_LANGUAGE_H_
 
 #include "vm/allocation.h"
 #include "vm/ast.h"
 #include "vm/growable_array.h"
@@ skipping 1689 matching lines @@
   M(GraphEntry)                                                                \
   M(JoinEntry)                                                                 \
   M(TargetEntry)                                                               \
   M(Do)                                                                        \
   M(Bind)                                                                      \
   M(Phi)                                                                       \
   M(Return)                                                                    \
   M(Throw)                                                                     \
   M(ReThrow)                                                                   \
   M(Branch)                                                                    \
-  M(ParallelMove)
+  M(ParallelMove)                                                              \
+  M(Parameter)
 
 
 // Forward declarations for Instruction classes.
 class BlockEntryInstr;
 class FlowGraphBuilder;
 class Environment;
 
 #define FORWARD_DECLARATION(type) class type##Instr;
 FOR_EACH_INSTRUCTION(FORWARD_DECLARATION)
 #undef FORWARD_DECLARATION
@@ skipping 259 matching lines @@
       GrowableArray<BlockEntryInstr*>* preorder,
       GrowableArray<BlockEntryInstr*>* postorder,
       GrowableArray<intptr_t>* parent,
       GrowableArray<BitVector*>* assigned_vars,
       intptr_t variable_count);
 
   void AddCatchEntry(TargetEntryInstr* entry) { catch_entries_.Add(entry); }
 
   virtual void PrepareEntry(FlowGraphCompiler* compiler);
 
-  ZoneGrowableArray<Value*>* start_env() const { return start_env_; }
-  void set_start_env(ZoneGrowableArray<Value*>* env) { start_env_ = env; }
+  Environment* start_env() const { return start_env_; }
+  void set_start_env(Environment* env) { start_env_ = env; }
 
  private:
   TargetEntryInstr* normal_entry_;
   GrowableArray<TargetEntryInstr*> catch_entries_;
-  ZoneGrowableArray<Value*>* start_env_;
+  Environment* start_env_;
 
   DISALLOW_COPY_AND_ASSIGN(GraphEntryInstr);
 };
 
 
 class JoinEntryInstr : public BlockEntryInstr {
  public:
   JoinEntryInstr()
       : BlockEntryInstr(),
         predecessors_(2),  // Two is the assumed to be the common case.
@@ skipping 175 matching lines @@
 
   DECLARE_INSTRUCTION(Phi)
 
  private:
   GrowableArray<Value*> inputs_;
 
   DISALLOW_COPY_AND_ASSIGN(PhiInstr);
 };
 
 
+class ParameterInstr: public Definition {
+ public:
+  explicit ParameterInstr(intptr_t index) : index_(index) { }
+
+  intptr_t index() const { return index_; }
+
+  DECLARE_INSTRUCTION(Parameter)
+
+ private:
+  intptr_t index_;
+
+  DISALLOW_COPY_AND_ASSIGN(ParameterInstr);
+};
+
+
 class ReturnInstr : public InstructionWithInputs {
  public:
   ReturnInstr(intptr_t token_pos, Value* value)
       : InstructionWithInputs(), token_pos_(token_pos), value_(value) {
     ASSERT(value_ != NULL);
   }
 
   DECLARE_INSTRUCTION(Return)
 
   Value* value() const { return value_; }
@@ skipping 218 matching lines @@
   const GrowableArray<BlockEntryInstr*>& block_order_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FlowGraphVisitor);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_