Recognize Math's min and max function for doubles and inline the operation.

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 562 matching lines @@
   M(SmiToDouble)                                                               \
   M(DoubleToInteger)                                                           \
   M(DoubleToSmi)                                                               \
   M(DoubleToDouble)                                                            \
   M(CheckClass)                                                                \
   M(CheckSmi)                                                                  \
   M(Constant)                                                                  \
   M(CheckEitherNonSmi)                                                         \
   M(BinaryDoubleOp)                                                            \
   M(MathSqrt)                                                                  \
+  M(MathMinMax)                                                                \
   M(UnboxDouble)                                                               \
   M(BoxDouble)                                                                 \
   M(BoxFloat32x4)                                                              \
   M(UnboxFloat32x4)                                                            \
   M(BoxUint32x4)                                                               \
   M(UnboxUint32x4)                                                             \
   M(UnboxInteger)                                                              \
   M(BoxInteger)                                                                \
   M(BinaryMintOp)                                                              \
   M(ShiftMintOp)                                                               \
@@ skipping 308 matching lines @@
   friend class Uint32x4SetFlagInstr;
   friend class Uint32x4SelectInstr;
   friend class Uint32x4ToFloat32x4Instr;
   friend class BinaryUint32x4OpInstr;
   friend class BinaryMintOpInstr;
   friend class BinarySmiOpInstr;
   friend class UnarySmiOpInstr;
   friend class ShiftMintOpInstr;
   friend class UnaryMintOpInstr;
   friend class MathSqrtInstr;
+  friend class MathMinMaxInstr;
   friend class CheckClassInstr;
   friend class GuardFieldInstr;
   friend class CheckSmiInstr;
   friend class CheckArrayBoundInstr;
   friend class CheckEitherNonSmiInstr;
   friend class LICM;
   friend class DoubleToSmiInstr;
   friend class DoubleToDoubleInstr;
   friend class InvokeMathCFunctionInstr;
   friend class FlowGraphOptimizer;
@@ skipping 3704 matching lines @@
   virtual EffectSet Dependencies() const { return EffectSet::None(); }
   virtual bool AttributesEqual(Instruction* other) const { return true; }
 
   virtual bool MayThrow() const { return false; }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MathSqrtInstr);
 };
 
 
+// Represents Math's static min and max functions.
+class MathMinMaxInstr : public TemplateDefinition<2> {
+ public:
+  MathMinMaxInstr(MethodRecognizer::Kind op_kind,
+                  Value* left_value,
+                  Value* right_value,
+                  intptr_t deopt_id,
+                  intptr_t result_cid)
+      : op_kind_(op_kind), result_cid_(result_cid) {
+    ASSERT((result_cid == kSmiCid) || (result_cid == kDoubleCid));
+    SetInputAt(0, left_value);
+    SetInputAt(1, right_value);
+    deopt_id_ = deopt_id;
+  }
+
+  MethodRecognizer::Kind op_kind() const { return op_kind_; }
+
+  Value* left() const { return inputs_[0]; }
+  Value* right() const { return inputs_[1]; }
+
+  intptr_t result_cid() const { return result_cid_; }
+
+  virtual bool CanDeoptimize() const { return false; }
+
+  virtual Representation representation() const {
+    if (result_cid() == kSmiCid) {
+      return kTagged;
+    }
+    ASSERT(result_cid() == kDoubleCid);
+    return kUnboxedDouble;
+  }
+
+  virtual Representation RequiredInputRepresentation(intptr_t idx) const {
+    if (result_cid() == kSmiCid) {
+      return kTagged;
+    }
+    ASSERT(result_cid() == kDoubleCid);
+    return kUnboxedDouble;
+  }
+
+  virtual intptr_t DeoptimizationTarget() const {
+    // Direct access since this instruction cannot deoptimize, and the deopt-id
+    // was inherited from another instruction that could deoptimize.
+    return deopt_id_;
+  }
+
+  DECLARE_INSTRUCTION(MathMinMax)
+  virtual CompileType ComputeType() const;
+  virtual bool AllowsCSE() const { return true; }
+  virtual EffectSet Effects() const { return EffectSet::None(); }
+  virtual EffectSet Dependencies() const { return EffectSet::None(); }
+  virtual bool AttributesEqual(Instruction* other) const;
+
+  virtual bool MayThrow() const { return false; }
+
+ private:
+  const MethodRecognizer::Kind op_kind_;
+  const intptr_t result_cid_;
+
+  DISALLOW_COPY_AND_ASSIGN(MathMinMaxInstr);
+};
+
+
 class BinaryDoubleOpInstr : public TemplateDefinition<2> {
  public:
   BinaryDoubleOpInstr(Token::Kind op_kind,
                       Value* left,
                       Value* right,
                       intptr_t deopt_id)
       : op_kind_(op_kind) {
     SetInputAt(0, left);
     SetInputAt(1, right);
     // Overrided generated deopt_id.
@@ skipping 1851 matching lines @@
   ForwardInstructionIterator* current_iterator_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FlowGraphVisitor);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_