PPC: Work-around to preserve sNan bit

src/ppc/macro-assembler-ppc.cc

 // Copyright 2014 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.
 
 #include <assert.h>  // For assert
 #include <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/base/bits.h"
@@ skipping 3663 matching lines @@
   subi(sp, sp, Operand(kFloatSize));
   stw(src, MemOperand(sp, 0));
   nop(GROUP_ENDING_NOP);  // LHS/RAW optimization
   lfs(dst, MemOperand(sp, 0));
   addi(sp, sp, Operand(kFloatSize));
 }
 
 
 void MacroAssembler::MovFloatToInt(Register dst, DoubleRegister src) {
   subi(sp, sp, Operand(kFloatSize));
-  frsp(src, src);
   stfs(src, MemOperand(sp, 0));
   nop(GROUP_ENDING_NOP);  // LHS/RAW optimization
   lwz(dst, MemOperand(sp, 0));
   addi(sp, sp, Operand(kFloatSize));
 }
 
 
 void MacroAssembler::Add(Register dst, Register src, intptr_t value,
                          Register scratch) {
   if (is_int16(value)) {
@@ skipping 700 matching lines @@
   }
   if (mag.shift > 0) srawi(result, result, mag.shift);
   ExtractBit(r0, dividend, 31);
   add(result, result, r0);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_PPC