A64: Rejig truncating and non double to i/smi

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 771 matching lines @@
                          Register heap_number_map,
                          Label* on_heap_number,
                          Label* on_not_heap_number = NULL);
   void JumpIfHeapNumber(Register object,
                         Label* on_heap_number,
                         Register heap_number_map = NoReg);
   void JumpIfNotHeapNumber(Register object,
                            Label* on_not_heap_number,
                            Register heap_number_map = NoReg);
 
+  // Jump to label if the input double register contains -0.0.
+  void JumpIfMinusZero(DoubleRegister input, Label* on_negative_zero);
+
   // Saturate a signed 32-bit integer in input to an unsigned 8-bit integer in
   // output.
   void ClampInt32ToUint8(Register in_out);
   void ClampInt32ToUint8(Register output, Register input);
 
   // Saturate a double in input to an unsigned 8-bit integer in output.
   void ClampDoubleToUint8(Register output,
                           DoubleRegister input,
                           DoubleRegister dbl_scratch);
 
@@ skipping 1314 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_