[hydrogen] optimize switch with string clauses

src/hydrogen-instructions.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 100 matching lines @@
   V(Goto)                                      \
   V(HasCachedArrayIndexAndBranch)              \
   V(HasInstanceTypeAndBranch)                  \
   V(In)                                        \
   V(InstanceOf)                                \
   V(InstanceOfKnownGlobal)                     \
   V(InvokeFunction)                            \
   V(IsConstructCallAndBranch)                  \
   V(IsNilAndBranch)                            \
   V(IsObjectAndBranch)                         \
+  V(IsStringAndBranch)                         \
   V(IsSmiAndBranch)                            \
   V(IsUndetectableAndBranch)                   \
+  V(CompareGenericAndBranch)                   \
   V(JSArrayLength)                             \
   V(LeaveInlined)                              \
   V(LoadContextSlot)                           \
   V(LoadElements)                              \
   V(LoadExternalArrayPointer)                  \
   V(LoadFunctionPrototype)                     \
   V(LoadGlobalCell)                            \
   V(LoadGlobalGeneric)                         \
   V(LoadKeyedFastDoubleElement)                \
   V(LoadKeyedFastElement)                      \
@@ skipping 2575 matching lines @@
   explicit HIsObjectAndBranch(HValue* value)
     : HUnaryControlInstruction(value, NULL, NULL) { }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(IsObjectAndBranch)
 };
 
+class HIsStringAndBranch: public HUnaryControlInstruction {
+ public:
+  explicit HIsStringAndBranch(HValue* value)
+    : HUnaryControlInstruction(value, NULL, NULL) { }
+
+  virtual Representation RequiredInputRepresentation(int index) {
+    return Representation::Tagged();
+  }
+
+  DECLARE_CONCRETE_INSTRUCTION(IsStringAndBranch)
+};
+
 
 class HIsSmiAndBranch: public HUnaryControlInstruction {
  public:
   explicit HIsSmiAndBranch(HValue* value)
       : HUnaryControlInstruction(value, NULL, NULL) { }
 
   DECLARE_CONCRETE_INSTRUCTION(IsSmiAndBranch)
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
@@ skipping 10 matching lines @@
       : HUnaryControlInstruction(value, NULL, NULL) { }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(IsUndetectableAndBranch)
 };
 
 
+class HCompareGenericAndBranch: public HTemplateControlInstruction<2, 3> {

[fschneider, 2011/11/07 08:27:18]

This should rather be HStringCompareAndBranch. It can't be used for generic
compares in general due to deoptimization.

+ public:
+  HCompareGenericAndBranch(HValue* context,
+                           HValue* left,
+                           HValue* right,
+                           Token::Value token)
+      : token_(token) {
+    ASSERT(Token::IsCompareOp(token));
+    SetOperandAt(0, context);
+    SetOperandAt(1, left);
+    SetOperandAt(2, right);
+    set_representation(Representation::Tagged());
+  }
+
+  HValue* context() { return OperandAt(0); }
+  HValue* left() { return OperandAt(1); }
+  HValue* right() { return OperandAt(2); }
+  Token::Value token() const { return token_; }
+
+  virtual void PrintDataTo(StringStream* stream);
+
+  virtual Representation RequiredInputRepresentation(int index) {
+    return Representation::Tagged();
+  }
+
+  Representation GetInputRepresentation() const {
+    return Representation::Tagged();
+  }
+
+  DECLARE_CONCRETE_INSTRUCTION(CompareGenericAndBranch)
+
+ private:
+  Token::Value token_;
+};
+
+
 class HIsConstructCallAndBranch: public HTemplateControlInstruction<2, 0> {
  public:
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::None();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(IsConstructCallAndBranch)
 };
 
 
@@ skipping 1527 matching lines @@
 
   DECLARE_CONCRETE_INSTRUCTION(In)
 };
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_