Eliminate map checks of constant values.

test/mjsunit/omit-constant-mapcheck.js

Index: test/mjsunit/omit-constant-mapcheck.js
diff --git a/test/mjsunit/regress/regress-int32-truncation.js b/test/mjsunit/omit-constant-mapcheck.js
similarity index 79%
copy from test/mjsunit/regress/regress-int32-truncation.js
copy to test/mjsunit/omit-constant-mapcheck.js
index dec4ac1195a6c4928d84eac8cc8dc9496bf66600..6894275db714875bedd6790036d4ada02812425e 100644
--- a/test/mjsunit/regress/regress-int32-truncation.js
+++ b/test/mjsunit/omit-constant-mapcheck.js
@@ -27,35 +27,29 @@
 
 // Flags: --allow-natives-syntax
 
-function f(i, b) {
-  var a = 0;
-  if (b) {
-    var c = 1 << i;
-    a = c + c;
-  }
-  var x = a >> 3;
-  return a;
-}
+var g1 = { a:1 }
 
-f(1, false);
-f(1, true);
-%OptimizeFunctionOnNextCall(f);
-assertEquals((1 << 30) * 2, f(30, true));
+function load() {
+  return g1.a;
+}
 
+assertEquals(1, load());
+assertEquals(1, load());
+%OptimizeFunctionOnNextCall(load);
+assertEquals(1, load());
+delete g1.a;
+assertEquals(undefined, load());
 
-var global = 1;
+var g2 = { a:2 }
 
-function f2(b) {
-  var a = 0;
-  if (b) {
-    a = global;
-  }
-  var x = a >> 3;
-  return a;
+function load2() {
+  return g2.a;
 }
 
-f2(false);
-f2(true);
-%OptimizeFunctionOnNextCall(f2);
-global = 2.5;
-assertEquals(global, f2(true));
+assertEquals(2, load2());
+assertEquals(2, load2());
+%OptimizeFunctionOnNextCall(load2);
+assertEquals(2, load2());
+g2.b = 10;
+g2.a = 5;
+assertEquals(5, load2());