Revert of [x86] Use AVX in Crankshaft when available.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 5d3d11be17d27668355507b42f4321575c9ba31a..c4e0a9df406396918285493e150328c2ea725962 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -1983,43 +1983,19 @@
   XMMRegister result = ToDoubleRegister(instr->result());
   switch (instr->op()) {
     case Token::ADD:
-      if (CpuFeatures::IsSupported(AVX)) {
-        CpuFeatureScope scope(masm(), AVX);
-        __ vaddsd(result, left, right);
-      } else {
-        DCHECK(result.is(left));
-        __ addsd(left, right);
-      }
+      __ addsd(left, right);
       break;
     case Token::SUB:
-      if (CpuFeatures::IsSupported(AVX)) {
-        CpuFeatureScope scope(masm(), AVX);
-        __ vsubsd(result, left, right);
-      } else {
-        DCHECK(result.is(left));
-        __ subsd(left, right);
-      }
+      __ subsd(left, right);
       break;
     case Token::MUL:
-      if (CpuFeatures::IsSupported(AVX)) {
-        CpuFeatureScope scope(masm(), AVX);
-        __ vmulsd(result, left, right);
-      } else {
-        DCHECK(result.is(left));
-        __ mulsd(left, right);
-      }
+      __ mulsd(left, right);
       break;
     case Token::DIV:
-      if (CpuFeatures::IsSupported(AVX)) {
-        CpuFeatureScope scope(masm(), AVX);
-        __ vdivsd(result, left, right);
-      } else {
-        DCHECK(result.is(left));
-        __ divsd(left, right);
-        // Don't delete this mov. It may improve performance on some CPUs,
-        // when there is a mulsd depending on the result
-        __ movaps(left, left);
-      }
+      __ divsd(left, right);
+      // Don't delete this mov. It may improve performance on some CPUs,
+      // when there is a mulsd depending on the result
+      __ movaps(left, left);
       break;
     case Token::MOD: {
       // Pass two doubles as arguments on the stack.