VM: Optimized context allocation on all platforms.

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 697 matching lines @@
   M(BooleanNegate)                                                             \
   M(InstanceOf)                                                                \
   M(CreateArray)                                                               \
   M(AllocateObject)                                                            \
   M(LoadField)                                                                 \
   M(LoadUntagged)                                                              \
   M(LoadClassId)                                                               \
   M(InstantiateType)                                                           \
   M(InstantiateTypeArguments)                                                  \
   M(AllocateContext)                                                           \
+  M(AllocateUninitializedContext)                                              \
   M(CloneContext)                                                              \
   M(BinarySmiOp)                                                               \
   M(UnarySmiOp)                                                                \
   M(UnaryDoubleOp)                                                             \
   M(CheckStackOverflow)                                                        \
   M(SmiToDouble)                                                               \
   M(DoubleToInteger)                                                           \
   M(DoubleToSmi)                                                               \
   M(DoubleToDouble)                                                            \
   M(DoubleToFloat)                                                             \
@@ skipping 4230 matching lines @@
   virtual bool MayThrow() const { return false; }
 
  private:
   const intptr_t token_pos_;
   const intptr_t num_context_variables_;
 
   DISALLOW_COPY_AND_ASSIGN(AllocateContextInstr);
 };
 
 
+class AllocateUninitializedContextInstr : public TemplateDefinition<0> {
+ public:
+  AllocateUninitializedContextInstr(intptr_t token_pos,
+                                    intptr_t num_context_variables)
+      : token_pos_(token_pos),
+        num_context_variables_(num_context_variables) {}
+
+  DECLARE_INSTRUCTION(AllocateUninitializedContext)
+  virtual CompileType ComputeType() const;
+
+  virtual intptr_t token_pos() const { return token_pos_; }
+  intptr_t num_context_variables() const { return num_context_variables_; }
+
+  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; }
+
+ private:
+  const intptr_t token_pos_;
+  const intptr_t num_context_variables_;
+
+  DISALLOW_COPY_AND_ASSIGN(AllocateUninitializedContextInstr);
+};
+
+
 class CloneContextInstr : public TemplateDefinition<1> {
  public:
   CloneContextInstr(intptr_t token_pos, Value* context_value)
       : token_pos_(token_pos) {
     SetInputAt(0, context_value);
   }
 
   virtual intptr_t token_pos() const { return token_pos_; }
   Value* context_value() const { return inputs_[0]; }
 
@@ skipping 3651 matching lines @@
   ForwardInstructionIterator* current_iterator_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FlowGraphVisitor);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_