Avoid a call to the runtime system when doing binary fp ops on ARM...

src/constants-arm.h

 // Copyright 2008 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 88 matching lines @@
 };
 
 
 // Special Software Interrupt codes when used in the presence of the ARM
 // simulator.
 enum SoftwareInterruptCodes {
   // transition to C code
   call_rt_r5 = 0x10,
   call_rt_r2 = 0x11,
   // break point
-  break_point = 0x20
+  break_point = 0x20,
+  // FP operations.  These simulate calling into C for a moment to do fp ops.
+  // They should trash all caller-save registers.
+  simulator_fp_add = 0x21,
+  simulator_fp_sub = 0x22,
+  simulator_fp_mul = 0x23
 };
 
 
 typedef int32_t instr_t;
 
 
 // The class Instr enables access to individual fields defined in the ARM
 // architecture instruction set encoding as described in figure A3-1.
 //
 // Example: Test whether the instruction at ptr does set the condition code
@@ skipping 106 matching lines @@
 
  private:
   // We need to prevent the creation of instances of class Instr.
   DISALLOW_IMPLICIT_CONSTRUCTORS(Instr);
 };
 
 
 } }  // namespace assembler::arm
 
 #endif  // V8_CONSTANTS_ARM_H_