[turbofan] Optimize loads of global constants in JSTypedLowering.

test/mjsunit/global-infinity.js

Index: test/mjsunit/global-infinity.js
diff --git a/test/mjsunit/global-infinity.js b/test/mjsunit/global-infinity.js
new file mode 100644
index 0000000000000000000000000000000000000000..33080579ae64ed2afa7fd6051ea4fc7ddd32836d
--- /dev/null
+++ b/test/mjsunit/global-infinity.js
@@ -0,0 +1,127 @@
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+function test(expected, f) {
+  assertEquals(expected, f());
+  assertEquals(expected, f());
+  %OptimizeFunctionOnNextCall(f);
+  assertEquals(expected, f());
+  assertEquals(expected, f());
+}
+
+function f1() { return Infinity; }
+test((1/0), f1);
+
+function f2() { return (1/0); }
+test((1/0), f2);
+
+function f3() { return (1/0) == (1/0); }
+test(true, f3);
+
+function f4() { return (1/0) == Infinity; }
+test(true, f4);
+
+function f5() { return Infinity == (1/0); }
+test(true, f5);
+
+function f6() { return "" + Infinity; }
+test("Infinity", f6);
+
+function f7() { return (1/0) === (1/0); }
+test(true, f7);
+
+function f8() { return (1/0) === Infinity; }
+test(true, f8);
+
+function f9() { return Infinity === (1/0); }
+test(true, f9);
+
+delete Infinity;
+
+function g1() { return Infinity; }
+test((1/0), g1);
+
+function g2() { return (1/0); }
+test((1/0), g2);
+
+function g3() { return (1/0) == (1/0); }
+test(true, g3);
+
+function g4() { return (1/0) == Infinity; }
+test(true, g4);
+
+function g5() { return Infinity == (1/0); }
+test(true, g5);
+
+function g6() { return "" + Infinity; }
+test("Infinity", g6);
+
+function g7() { return (1/0) === (1/0); }
+test(true, g7);
+
+function g8() { return (1/0) === Infinity; }
+test(true, g8);
+
+function g9() { return Infinity === (1/0); }
+test(true, g9);
+
+Infinity = 111;
+
+function h1() { return Infinity; }
+test((1/0), h1);
+
+function h2() { return (1/0); }
+test((1/0), h2);
+
+function h3() { return (1/0) == (1/0); }
+test(true, h3);
+
+function h4() { return (1/0) == Infinity; }
+test(true, h4);
+
+function h5() { return Infinity == (1/0); }
+test(true, h5);
+
+function h6() { return "" + Infinity; }
+test("Infinity", h6);
+
+function h7() { return (1/0) === (1/0); }
+test(true, h7);
+
+function h8() { return (1/0) === Infinity; }
+test(true, h8);
+
+function h9() { return Infinity === (1/0); }
+test(true, h9);
+
+// -------------
+
+function k1() { return this.Infinity; }
+test((1/0), k1);
+
+function k2() { return (1/0); }
+test((1/0), k2);
+
+function k3() { return (1/0) == (1/0); }
+test(true, k3);
+
+function k4() { return (1/0) == this.Infinity; }
+test(true, k4);
+
+function k5() { return this.Infinity == (1/0); }
+test(true, k5);
+
+function k6() { return "" + this.Infinity; }
+test("Infinity", k6);
+
+function k7() { return (1/0) === (1/0); }
+test(true, k7);
+
+function k8() { return (1/0) === this.Infinity; }
+test(true, k8);
+
+function k9() { return this.Infinity === (1/0); }
+test(true, k9);