Add alias identity information to array allocations.

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 1688 matching lines @@
   const intptr_t catch_try_index_;
   GrowableArray<Definition*> initial_definitions_;
   const LocalVariable& exception_var_;
   const LocalVariable& stacktrace_var_;
   const bool needs_stacktrace_;
 
   DISALLOW_COPY_AND_ASSIGN(CatchBlockEntryInstr);
 };
 
 
+// If the result of the allocation is not stored into any field, passed
+// as an argument or used in a phi then it can't alias with any other
+// SSA value.
+enum AliasIdentity {
+  kIdentityUnknown,
+  kIdentityAliased,
+  kIdentityNotAliased
+};
+
+
 // Abstract super-class of all instructions that define a value (Bind, Phi).
 class Definition : public Instruction {
  public:
   enum UseKind { kEffect, kValue };
 
   Definition();
 
   virtual Definition* AsDefinition() { return this; }
 
   bool IsComparison() { return (AsComparison() != NULL); }
@@ skipping 117 matching lines @@
     return this;
   }
 
   void SetReplacement(Definition* other) {
     ASSERT(ssa_temp_index_ >= 0);
     ASSERT(WasEliminated());
     ssa_temp_index_ = kReplacementMarker;
     temp_index_ = reinterpret_cast<intptr_t>(other);
   }
 
+  virtual AliasIdentity Identity() const {
+    // Only implemented for allocation instructions.
+    UNREACHABLE();
+    return kIdentityUnknown;
+  }
+
+  virtual void SetIdentity(AliasIdentity identity) {
+    UNREACHABLE();
+  }
+
  protected:
   friend class RangeAnalysis;
   friend class Value;
 
   Range* range_;
   CompileType* type_;
 
  private:
   intptr_t temp_index_;
   intptr_t ssa_temp_index_;
@@ skipping 1402 matching lines @@
                   const Array& argument_names,
                   ZoneGrowableArray<PushArgumentInstr*>* arguments,
                   const Array& ic_data_array)
       : ic_data_(GetICData(ic_data_array)),
         token_pos_(token_pos),
         function_(function),
         argument_names_(argument_names),
         arguments_(arguments),
         result_cid_(kDynamicCid),
         is_known_list_constructor_(false),
-        is_native_list_factory_(false) {
+        is_native_list_factory_(false),
+        identity_(kIdentityUnknown) {
     ASSERT(function.IsZoneHandle());
     ASSERT(argument_names.IsZoneHandle() ||  argument_names.InVMHeap());
   }
 
   // ICData for static calls carries call count.
   const ICData* ic_data() const { return ic_data_; }
   bool HasICData() const {
     return (ic_data() != NULL) && !ic_data()->IsNull();
   }
 
@@ skipping 25 matching lines @@
     is_known_list_constructor_ = value;
   }
 
   bool is_native_list_factory() const { return is_native_list_factory_; }
   void set_is_native_list_factory(bool value) {
     is_native_list_factory_ = value;
   }
 
   virtual bool MayThrow() const { return true; }
 
+  virtual AliasIdentity Identity() const { return identity_; }
+  virtual void SetIdentity(AliasIdentity identity) { identity_ = identity; }
+
  private:
   const ICData* ic_data_;
   const intptr_t token_pos_;
   const Function& function_;
   const Array& argument_names_;
   ZoneGrowableArray<PushArgumentInstr*>* arguments_;
   intptr_t result_cid_;  // For some library functions we know the result.
 
   // 'True' for recognized list constructors.
   bool is_known_list_constructor_;
   bool is_native_list_factory_;
 
+  AliasIdentity identity_;
+
   DISALLOW_COPY_AND_ASSIGN(StaticCallInstr);
 };
 
 
 class LoadLocalInstr : public TemplateDefinition<0> {
  public:
   explicit LoadLocalInstr(const LocalVariable& local)
       : local_(local), is_last_(false) { }
 
   DECLARE_INSTRUCTION(LoadLocal)
@@ skipping 694 matching lines @@
 
 
 class AllocateObjectInstr : public TemplateDefinition<0> {
  public:
   AllocateObjectInstr(intptr_t token_pos,
                       const Class& cls,
                       ZoneGrowableArray<PushArgumentInstr*>* arguments)
       : token_pos_(token_pos),
         cls_(cls),
         arguments_(arguments),
-        identity_(kUnknown),
+        identity_(kIdentityUnknown),
         closure_function_(Function::ZoneHandle()) {
     // Either no arguments or one type-argument and one instantiator.
     ASSERT(arguments->is_empty() || (arguments->length() == 1));
   }
 
   DECLARE_INSTRUCTION(AllocateObject)
   virtual CompileType ComputeType() const;
 
   virtual intptr_t ArgumentCount() const { return arguments_->length(); }
   virtual PushArgumentInstr* PushArgumentAt(intptr_t index) const {
     return (*arguments_)[index];
   }
 
   const Class& cls() const { return cls_; }
   intptr_t token_pos() const { return token_pos_; }
 
   const Function& closure_function() const { return closure_function_; }
   void set_closure_function(const Function& function) {
     closure_function_ ^= function.raw();
   }
 
   virtual void PrintOperandsTo(BufferFormatter* f) const;
 
   virtual bool CanDeoptimize() const { return false; }
 
   virtual EffectSet Effects() const { return EffectSet::None(); }
 
   virtual bool MayThrow() const { return false; }
 
-  // If the result of the allocation is not stored into any field, passed
-  // as an argument or used in a phi then it can't alias with any other
-  // SSA value.
-  enum Identity {
-    kUnknown,
-    kAliased,
-    kNotAliased
-  };
-
-  Identity identity() const { return identity_; }
-  void set_identity(Identity identity) { identity_ = identity; }
+  virtual AliasIdentity Identity() const { return identity_; }
+  virtual void SetIdentity(AliasIdentity identity) { identity_ = identity; }
 
  private:
   const intptr_t token_pos_;
   const Class& cls_;
   ZoneGrowableArray<PushArgumentInstr*>* const arguments_;
-  Identity identity_;
+  AliasIdentity identity_;
   Function& closure_function_;
 
   DISALLOW_COPY_AND_ASSIGN(AllocateObjectInstr);
 };
 
 
 // This instruction captures the state of the object which had its allocation
 // removed during the AllocationSinking pass.
 // It does not produce any real code only deoptimization information.
 class MaterializeObjectInstr : public Definition {
@@ skipping 60 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(MaterializeObjectInstr);
 };
 
 
 class CreateArrayInstr : public TemplateDefinition<2> {
  public:
   CreateArrayInstr(intptr_t token_pos,
                    Value* element_type,
                    Value* num_elements)
-      : token_pos_(token_pos) {
+      : token_pos_(token_pos), identity_(kIdentityUnknown)  {
     SetInputAt(kElementTypePos, element_type);
     SetInputAt(kLengthPos, num_elements);
   }
 
   enum {
     kElementTypePos = 0,
     kLengthPos = 1
   };
 
   DECLARE_INSTRUCTION(CreateArray)
   virtual CompileType ComputeType() const;
 
 
   intptr_t token_pos() const { return token_pos_; }
   Value* element_type() const { return inputs_[kElementTypePos]; }
   Value* num_elements() const { return inputs_[kLengthPos]; }
 
   virtual void PrintOperandsTo(BufferFormatter* f) const;
 
   virtual bool CanDeoptimize() const { return false; }
 
   virtual EffectSet Effects() const { return EffectSet::None(); }
 
   virtual bool MayThrow() const { return false; }
 
+  virtual AliasIdentity Identity() const { return identity_; }
+  virtual void SetIdentity(AliasIdentity identity) { identity_ = identity; }
+
  private:
   const intptr_t token_pos_;
+  AliasIdentity identity_;
 
   DISALLOW_COPY_AND_ASSIGN(CreateArrayInstr);
 };
 
 
 class LoadUntaggedInstr : public TemplateDefinition<1> {
  public:
   LoadUntaggedInstr(Value* object, intptr_t offset) : offset_(offset) {
     SetInputAt(0, object);
   }
@@ skipping 3351 matching lines @@
   ForwardInstructionIterator* current_iterator_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FlowGraphVisitor);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_