Implement Math.pow using FPU instructions and inline it in crankshaft (ia32).

src/x64/assembler-x64.cc

Index: src/x64/assembler-x64.cc
diff --git a/src/x64/assembler-x64.cc b/src/x64/assembler-x64.cc
index d578bf9c57b7fd7e84927b1f760f0f5f41a49e6c..26b449c524690ee69b4a71a227b7790f8a0faa06 100644
--- a/src/x64/assembler-x64.cc
+++ b/src/x64/assembler-x64.cc
@@ -2572,7 +2572,8 @@ void Assembler::movdqa(XMMRegister dst, const Operand& src) {
 
 
 void Assembler::extractps(Register dst, XMMRegister src, byte imm8) {
-  ASSERT(is_uint2(imm8));
+  ASSERT(CpuFeatures::IsSupported(SSE4_1));
+  ASSERT(is_uint8(imm8));
   EnsureSpace ensure_space(this);
   emit(0x66);
   emit_optional_rex_32(dst, src);