Expose SIMD.Float32x4 type to Javascript.

src/x87/lithium-codegen-x87.cc

Index: src/x87/lithium-codegen-x87.cc
diff --git a/src/x87/lithium-codegen-x87.cc b/src/x87/lithium-codegen-x87.cc
index 9c6798b136f8fa100f308df08eb2c6961353cf31..a77771d1962bd257673d645e5b2b212754df13a9 100644
--- a/src/x87/lithium-codegen-x87.cc
+++ b/src/x87/lithium-codegen-x87.cc
@@ -2434,6 +2434,12 @@ void LCodeGen::DoBranch(LBranch* instr) {
         __ j(equal, instr->TrueLabel(chunk_));
       }
 
+      if (expected.Contains(ToBooleanStub::SIMD_VALUE)) {
+        // SIMD value -> true.
+        __ CmpInstanceType(map, FLOAT32X4_TYPE);
+        __ j(equal, instr->TrueLabel(chunk_));
+      }
+
       if (expected.Contains(ToBooleanStub::HEAP_NUMBER)) {
         // heap number -> false iff +0, -0, or NaN.
         Label not_heap_number;
@@ -6121,6 +6127,11 @@ Condition LCodeGen::EmitTypeofIs(LTypeofIsAndBranch* instr, Register input) {
               1 << Map::kIsUndetectable);
     final_branch_condition = zero;
 
+  } else if (String::Equals(type_name, factory()->float32x4_string())) {
+    __ JumpIfSmi(input, false_label, false_distance);
+    __ CmpObjectType(input, FLOAT32X4_TYPE, input);
+    final_branch_condition = equal;
+
   } else {
     __ jmp(false_label, false_distance);
   }