[builtins] Introduce proper Float64Cos and Float64Sin.

test/unittests/compiler/js-builtin-reducer-unittest.cc

Index: test/unittests/compiler/js-builtin-reducer-unittest.cc
diff --git a/test/unittests/compiler/js-builtin-reducer-unittest.cc b/test/unittests/compiler/js-builtin-reducer-unittest.cc
index 60d996cca2a1b0f7e8f4460a5484e002b2d01a04..0c282d495955d6c3abb02d2b1d060bb06f6e6883 100644
--- a/test/unittests/compiler/js-builtin-reducer-unittest.cc
+++ b/test/unittests/compiler/js-builtin-reducer-unittest.cc
@@ -264,6 +264,45 @@ TEST_F(JSBuiltinReducerTest, MathClz32WithPlainPrimitive) {
 }
 
 // -----------------------------------------------------------------------------
+// Math.cos
+
+TEST_F(JSBuiltinReducerTest, MathCosWithNumber) {
+  Node* function = MathFunction("cos");
+
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+  TRACED_FOREACH(Type*, t0, kNumberTypes) {
+    Node* p0 = Parameter(t0, 0);
+    Node* call = graph()->NewNode(javascript()->CallFunction(3), function,
+                                  UndefinedConstant(), p0, context, frame_state,
+                                  effect, control);
+    Reduction r = Reduce(call);
+
+    ASSERT_TRUE(r.Changed());
+    EXPECT_THAT(r.replacement(), IsNumberCos(p0));
+  }
+}
+
+TEST_F(JSBuiltinReducerTest, MathCosWithPlainPrimitive) {
+  Node* function = MathFunction("cos");
+
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+  Node* p0 = Parameter(Type::PlainPrimitive(), 0);
+  Node* call = graph()->NewNode(javascript()->CallFunction(3), function,
+                                UndefinedConstant(), p0, context, frame_state,
+                                effect, control);
+  Reduction r = Reduce(call);
+
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(), IsNumberCos(IsPlainPrimitiveToNumber(p0)));
+}
+
+// -----------------------------------------------------------------------------
 // Math.exp
 
 TEST_F(JSBuiltinReducerTest, MathExpWithNumber) {