[turbofan] Improve typed lowering for JSToBoolean.

test/unittests/compiler/js-typed-lowering-unittest.cc

Index: test/unittests/compiler/js-typed-lowering-unittest.cc
diff --git a/test/unittests/compiler/js-typed-lowering-unittest.cc b/test/unittests/compiler/js-typed-lowering-unittest.cc
index 3da4bc71683a75e82c19ee7dedeadfd066c5d3c5..81b48a64d69c6c88c847bde59f989580b9f7fcbf 100644
--- a/test/unittests/compiler/js-typed-lowering-unittest.cc
+++ b/test/unittests/compiler/js-typed-lowering-unittest.cc
@@ -69,6 +69,46 @@ class JSTypedLoweringTest : public TypedGraphTest {
 
 
 // -----------------------------------------------------------------------------
+// JSToBoolean
+
+
+TEST_F(JSTypedLoweringTest, JSToBooleanWithString) {
+  Node* input = Parameter(Type::String());
+  Node* context = UndefinedConstant();
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+
+  Reduction r = Reduce(graph()->NewNode(javascript()->ToBoolean(), input,
+                                        context, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsBooleanNot(IsNumberEqual(
+                  IsLoadField(AccessBuilder::ForStringLength(), input,
+                              graph()->start(), graph()->start()),
+                  IsNumberConstant(0))));
+}
+
+
+TEST_F(JSTypedLoweringTest, JSToBooleanWithOrderedNumberAndBoolean) {
+  Node* p0 = Parameter(Type::OrderedNumber(), 0);
+  Node* p1 = Parameter(Type::Boolean(), 1);
+  Node* context = UndefinedConstant();
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->ToBoolean(),
+      graph()->NewNode(common()->Phi(kMachAnyTagged, 2), p0, p1, control),
+      context, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(
+      r.replacement(),
+      IsPhi(kMachAnyTagged,
+            IsBooleanNot(IsNumberEqual(p0, IsNumberConstant(0))), p1, control));
+}
+
+
+// -----------------------------------------------------------------------------
 // JSLoadProperty