Take all uses into account to clear int32 truncation.

test/mjsunit/regress/regress-int32-truncation.js

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 // Flags: --allow-natives-syntax
 
-"use strict";
-
-function f(a, b) {
-  return g("c", "d");
+function f(i, b) {
+  var a = 0;
+  if (b) {
+    var c = 1 << i;
+    a = c + c;
+  }
+  var x = a >> 3;
+  return a;
 }
 
-function g(a, b) {
-  g.constructor.apply(this, arguments);
+f(1, false);
+f(1, true);
+%OptimizeFunctionOnNextCall(f);
+assertEquals((1<<30)*2, f(30, true));

[Jakob Kummerow, 2013/06/07 17:22:45]

nit: spaces around operators, please

+
+
+var global = 1;
+
+function f2(b) {
+  var a = 0;
+  if (b) {
+    a = global;
+  }
+  var x = a >> 3;
+  return a;
 }
 
-g.constructor = function(a, b) {
-  assertEquals("c", a);
-  assertEquals("d", b);
-}
-
-f("a", "b");
-f("a", "b");
-%OptimizeFunctionOnNextCall(f);
-f("a", "b");
-g.x = "deopt";
-f("a", "b");
+f2(false);
+f2(true);
+%OptimizeFunctionOnNextCall(f2);
+global = 2.5;
+assertEquals(global, f2(true));