ARM64: Use the shifter operand to merge in previous shift instructions.

src/arm64/lithium-codegen-arm64.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ARM64_LITHIUM_CODEGEN_ARM64_H_
 #define V8_ARM64_LITHIUM_CODEGEN_ARM64_H_
 
 #include "arm64/lithium-arm64.h"
 
 #include "arm64/lithium-gap-resolver-arm64.h"
@@ skipping 63 matching lines @@
 
   // Try to generate code for the entire chunk, but it may fail if the
   // chunk contains constructs we cannot handle. Returns true if the
   // code generation attempt succeeded.
   bool GenerateCode();
 
   // Finish the code by setting stack height, safepoint, and bailout
   // information on it.
   void FinishCode(Handle<Code> code);
 
+  enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
   // Support for converting LOperands to assembler types.
   // LOperand must be a register.
   Register ToRegister(LOperand* op) const;
   Register ToRegister32(LOperand* op) const;
   Operand ToOperand(LOperand* op);
   Operand ToOperand32I(LOperand* op);
   Operand ToOperand32U(LOperand* op);
   enum StackMode { kMustUseFramePointer, kCanUseStackPointer };
   MemOperand ToMemOperand(LOperand* op,
                           StackMode stack_mode = kCanUseStackPointer) const;
   Handle<Object> ToHandle(LConstantOperand* op) const;
 
+  template<class LI>
+  Operand ToShiftedRightOperand32I(LOperand* right,
+                                   LI* shift_info) {
+    return ToShiftedRightOperand32(right, shift_info, SIGNED_INT32);
+  }
+  template<class LI>
+  Operand ToShiftedRightOperand32U(LOperand* right,
+                                   LI* shift_info) {
+    return ToShiftedRightOperand32(right, shift_info, UNSIGNED_INT32);
+  }
+  template<class LI>
+  Operand ToShiftedRightOperand32(LOperand* right,
+                                  LI* shift_info,
+                                  IntegerSignedness signedness);
+
+  int JSShiftAmountFromLConstant(LOperand* constant) {
+    return ToInteger32(LConstantOperand::cast(constant)) & 0x1f;
+  }
+
   // TODO(jbramley): Examine these helpers and check that they make sense.
   // IsInteger32Constant returns true for smi constants, for example.
   bool IsInteger32Constant(LConstantOperand* op) const;
   bool IsSmi(LConstantOperand* op) const;
 
   int32_t ToInteger32(LConstantOperand* op) const;
   Smi* ToSmi(LConstantOperand* op) const;
   double ToDouble(LConstantOperand* op) const;
   DoubleRegister ToDoubleRegister(LOperand* op) const;
 
   // Declare methods that deal with the individual node types.
 #define DECLARE_DO(type) void Do##type(L##type* node);
   LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
 #undef DECLARE_DO
 
  private:
   // Return a double scratch register which can be used locally
   // when generating code for a lithium instruction.
   DoubleRegister double_scratch() { return crankshaft_fp_scratch; }
 
   // Deferred code support.
   void DoDeferredNumberTagD(LNumberTagD* instr);
   void DoDeferredStackCheck(LStackCheck* instr);
   void DoDeferredStringCharCodeAt(LStringCharCodeAt* instr);
   void DoDeferredStringCharFromCode(LStringCharFromCode* instr);
   void DoDeferredMathAbsTagged(LMathAbsTagged* instr,
                                Label* exit,
                                Label* allocation_entry);
 
-  enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
   void DoDeferredNumberTagU(LInstruction* instr,
                             LOperand* value,
                             LOperand* temp1,
                             LOperand* temp2);
   void DoDeferredTaggedToI(LTaggedToI* instr,
                            LOperand* value,
                            LOperand* temp1,
                            LOperand* temp2);
   void DoDeferredAllocate(LAllocate* instr);
   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr);
@@ skipping 340 matching lines @@
 
  protected:
   MacroAssembler* masm() const { return codegen_->masm(); }
 
   LCodeGen* codegen_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM64_LITHIUM_CODEGEN_ARM64_H_