ARM64: Generate better immediates for shifted ops

src/arm64/macro-assembler-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_MACRO_ASSEMBLER_ARM64_H_
 #define V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
 
 #include <vector>
 
 #include "src/globals.h"
@@ skipping 184 matching lines @@
   void Mov(const Register& rd,
            const Operand& operand,
            DiscardMoveMode discard_mode = kDontDiscardForSameWReg);
   void Mov(const Register& rd, uint64_t imm);
   inline void Mvn(const Register& rd, uint64_t imm);
   void Mvn(const Register& rd, const Operand& operand);
   static bool IsImmMovn(uint64_t imm, unsigned reg_size);
   static bool IsImmMovz(uint64_t imm, unsigned reg_size);
   static unsigned CountClearHalfWords(uint64_t imm, unsigned reg_size);
 
+  // Try to move an immediate into the destination register in a single
+  // instruction. Returns true for success, and updates the contents of dst.
+  // Returns false, otherwise.
+  bool TryOneInstrMoveImmediate(const Register& dst, int64_t imm);
+
+  // Move an immediate into register dst, and return an Operand object for use
+  // with a subsequent instruction that accepts a shift. The value moved into
+  // dst is not necessarily equal to imm; it may have had a shifting operation
+  // applied to it that will be subsequently undone by the shift applied in the
+  // Operand.
+  Operand MoveImmediateForShiftedOp(const Register& dst, int64_t imm);
+
   // Conditional macros.
   inline void Ccmp(const Register& rn,
                    const Operand& operand,
                    StatusFlags nzcv,
                    Condition cond);
   inline void Ccmn(const Register& rn,
                    const Operand& operand,
                    StatusFlags nzcv,
                    Condition cond);
   void ConditionalCompareMacro(const Register& rn,
@@ skipping 2105 matching lines @@
 #error "Unsupported option"
 #define CODE_COVERAGE_STRINGIFY(x) #x
 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 #endif  // V8_ARM64_MACRO_ASSEMBLER_ARM64_H_