Use integer division in a certain case.

test/mjsunit/fast-div-int.js

+// Copyright 2009 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax
+
+function SlowDiv(a, b) {
+  var aInt = 0 | a;
+  var bInt = 0 | b;
+  return 0 | aInt / bInt;
+}
+
+function FastDiv(a, b) {
+  var aInt = 0 | a;
+  var bInt = 0 | b;
+  return aInt >= 0 && bInt > 0 ? 0 | aInt / bInt : 0;
+}
+
+SlowDiv(1, 2);
+%OptimizeFunctionOnNextCall(SlowDiv);
+SlowDiv(1, 2);
+
+FastDiv(1, 2);
+%OptimizeFunctionOnNextCall(FastDiv);
+FastDiv(1, 2);
+
+var SMI_MAX = (1 << 30) - 1;
+var ints = [
+  0,
+  1,
+  2,
+  3,
+  SMI_MAX - 3,
+  SMI_MAX - 2,
+  SMI_MAX - 1,
+  SMI_MAX
+];
+
+for (var a = 0; a < ints.length; a++) {
+  for (var b = 0; b < ints.length; b++) {
+    assertEquals(SlowDiv(ints[a], ints[b]), FastDiv(ints[a], ints[b]));
+  }
+}