[builtins] Introduce proper Float64Atan and Float64Atan2 operators.

test/unittests/compiler/machine-operator-reducer-unittest.cc

Index: test/unittests/compiler/machine-operator-reducer-unittest.cc
diff --git a/test/unittests/compiler/machine-operator-reducer-unittest.cc b/test/unittests/compiler/machine-operator-reducer-unittest.cc
index d9b6ea74033521ce068f5c7cc610bc810dd3ca98..9d7482af76df973f45b98cac3391179fa43cdecd 100644
--- a/test/unittests/compiler/machine-operator-reducer-unittest.cc
+++ b/test/unittests/compiler/machine-operator-reducer-unittest.cc
@@ -1401,6 +1401,53 @@ TEST_F(MachineOperatorReducerTest, Float64MulWithMinusOne) {
 
 
 // -----------------------------------------------------------------------------
+// Float64Atan
+
+TEST_F(MachineOperatorReducerTest, Float64AtanWithConstant) {
+  TRACED_FOREACH(double, x, kFloat64Values) {
+    Reduction const r =
+        Reduce(graph()->NewNode(machine()->Float64Atan(), Float64Constant(x)));
+    ASSERT_TRUE(r.Changed());
+    EXPECT_THAT(
+        r.replacement(),
+        IsFloat64Constant(NanSensitiveDoubleEq(base::ieee754::atan(x))));
+  }
+}
+
+// -----------------------------------------------------------------------------
+// Float64Atan2
+
+TEST_F(MachineOperatorReducerTest, Float64Atan2WithConstant) {
+  TRACED_FOREACH(double, y, kFloat64Values) {
+    TRACED_FOREACH(double, x, kFloat64Values) {
+      Reduction const r = Reduce(graph()->NewNode(
+          machine()->Float64Atan2(), Float64Constant(y), Float64Constant(x)));
+      ASSERT_TRUE(r.Changed());
+      EXPECT_THAT(
+          r.replacement(),
+          IsFloat64Constant(NanSensitiveDoubleEq(base::ieee754::atan2(y, x))));
+    }
+  }
+}
+
+TEST_F(MachineOperatorReducerTest, Float64Atan2WithNaN) {
+  Node* const p0 = Parameter(0);
+  Node* const nan = Float64Constant(std::numeric_limits<double>::quiet_NaN());
+  {
+    Reduction const r =
+        Reduce(graph()->NewNode(machine()->Float64Atan2(), p0, nan));
+    ASSERT_TRUE(r.Changed());
+    EXPECT_EQ(nan, r.replacement());
+  }
+  {
+    Reduction const r =
+        Reduce(graph()->NewNode(machine()->Float64Atan2(), nan, p0));
+    ASSERT_TRUE(r.Changed());
+    EXPECT_EQ(nan, r.replacement());
+  }
+}
+
+// -----------------------------------------------------------------------------
 // Float64Log
 
 TEST_F(MachineOperatorReducerTest, Float64LogWithConstant) {