Handle non-power-of-2 divisors in division-like operations

src/a64/macro-assembler-a64.h

 // Copyright 2013 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 1659 matching lines @@
   //  * The exit frame is dropped.
   //  * The stack pointer is reset to jssp.
   //
   // The stack pointer must be csp on entry.
   void LeaveExitFrame(bool save_doubles,
                       const Register& scratch,
                       bool restore_context);
 
   void LoadContext(Register dst, int context_chain_length);
 
+  // Emit code for a flooring division by a constant. The dividend register is
+  // unchanged and Tmp0() gets clobbered. Dividend and result must be different.
+  void FlooringDiv(Register result, Register dividend, int32_t divisor);
+
   // ---------------------------------------------------------------------------
   // StatsCounter support
 
   void SetCounter(StatsCounter* counter, int value, Register scratch1,
                   Register scratch2);
   void IncrementCounter(StatsCounter* counter, int value, Register scratch1,
                         Register scratch2);
   void DecrementCounter(StatsCounter* counter, int value, Register scratch1,
                         Register scratch2);
 
@@ skipping 601 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_A64_MACRO_ASSEMBLER_A64_H_