ARM: Fix bug introduced in 4783 (2.2.15) that caused the...

test/mjsunit/smi-ops.js

 // Copyright 2008 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
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@@ skipping 667 matching lines @@
 
 assertEquals(4589934592, LogicalShiftRightByMultipleOf32(-2000000000));
 assertEquals(4589934592, LogicalShiftRightByMultipleOf32(-2000000000));
 
 // Verify that the shift amount is reduced modulo 32, not modulo 64.
 function LeftShiftThreeBy(x) {return 3 << x;}
 assertEquals(24, LeftShiftThreeBy(3));
 assertEquals(24, LeftShiftThreeBy(35));
 assertEquals(24, LeftShiftThreeBy(67));
 assertEquals(24, LeftShiftThreeBy(-29));
+
+// Regression test for a bug in the ARM code generator.  For some register
+// allocations we got the Smi overflow case wrong.
+function f(x, y) { return y +  ( 1 << (x & 31)); }
+assertEquals(-2147483647, f(31, 1));