Mark ptest instruction as requiring SSE4.1.

src/ia32/assembler-ia32.h

Index: src/ia32/assembler-ia32.h
diff --git a/src/ia32/assembler-ia32.h b/src/ia32/assembler-ia32.h
index 1dab0a608cdd87cea5f9e383715820181e701828..d8051c8719a449e7d8ac92522cb8c61139403f6c 100644
--- a/src/ia32/assembler-ia32.h
+++ b/src/ia32/assembler-ia32.h
@@ -376,6 +376,7 @@ class CpuFeatures : public AllStatic {
   static bool IsSupported(CpuFeature f) {
     if (f == SSE2 && !FLAG_enable_sse2) return false;
     if (f == SSE3 && !FLAG_enable_sse3) return false;
+    if (f == SSE4_1 && !FLAG_enable_sse4_1) return false;
     if (f == CMOV && !FLAG_enable_cmov) return false;
     if (f == RDTSC && !FLAG_enable_rdtsc) return false;
     return (supported_ & (static_cast<uint64_t>(1) << f)) != 0;