[turbofan] Also optimize unsigned division by constant.

test/mjsunit/asm/uint32div.js

Index: test/mjsunit/asm/uint32div.js
diff --git a/test/mjsunit/asm/int32div.js b/test/mjsunit/asm/uint32div.js
similarity index 55%
copy from test/mjsunit/asm/int32div.js
copy to test/mjsunit/asm/uint32div.js
index f5d24331ed0a26179fa298d628196c9cb55d0361..54a2138786692ebf24e7e3e7d21cda2879e39952 100644
--- a/test/mjsunit/asm/int32div.js
+++ b/test/mjsunit/asm/uint32div.js
@@ -6,28 +6,24 @@ var stdlib = {};
 var foreign = {};
 var heap = new ArrayBuffer(64 * 1024);
 
-function Int32Div(divisor) {
+function Uint32Div(divisor) {
   var name = "div_";
-  if (divisor < 0) {
-    name += "minus_";
-  }
-  name += Math.abs(divisor);
+  name += divisor;
   var m = eval("function Module(stdlib, foreign, heap) {\n"
       + " \"use asm\";\n"
       + " function " + name + "(dividend) {\n"
-      + "  return ((dividend | 0) / " + divisor + ") | 0;\n"
+      + "  return ((dividend >>> 0) / " + divisor + ") >>> 0;\n"
       + " }\n"
       + " return { f: " + name + "}\n"
       + "}; Module");
   return m(stdlib, foreign, heap).f;
 }
 
-var divisors = [-2147483648, -32 * 1024, -1000, -16, -7, -2, -1, 0,
-                1, 3, 4, 10, 64, 100, 1024, 2147483647];
+var divisors = [0, 1, 3, 4, 10, 42, 64, 100, 1024, 2147483647, 4294967295];
 for (var i in divisors) {
   var divisor = divisors[i];
-  var div = Int32Div(divisor);
-  for (var dividend = -2147483648; dividend < 2147483648; dividend += 3999773) {
-    assertEquals((dividend / divisor) | 0, div(dividend));
+  var mod = Uint32Div(divisor);
+  for (var dividend = 0; dividend < 4294967296; dividend += 3999773) {
+    assertEquals((dividend / divisor) >>> 0, mod(dividend));
   }
 }