Extend test case to check truncation and 64-bit ints.

test/mjsunit/toint32.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
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 24 matching lines @@
 assertEquals(0, toInt32(0.0));
 assertEquals(0, toInt32(-0.0));
 
 assertEquals(0, toInt32(Number.MIN_VALUE));
 assertEquals(0, toInt32(-Number.MIN_VALUE));
 assertEquals(0, toInt32(0.1));
 assertEquals(0, toInt32(-0.1));
 assertEquals(1, toInt32(1));
 assertEquals(1, toInt32(1.1));
 assertEquals(-1, toInt32(-1));
+assertEquals(0, toInt32(0.6), "truncate positive (0.6)");
+assertEquals(1, toInt32(1.6), "truncate positive (1.6)");
+assertEquals(0, toInt32(-0.6), "truncate negative (-0.6)");
+assertEquals(-1, toInt32(-1.6), "truncate negative (-1.6)");
 
 assertEquals(2147483647, toInt32(2147483647));
 assertEquals(-2147483648, toInt32(2147483648));
 assertEquals(-2147483647, toInt32(2147483649));
 
 assertEquals(-1, toInt32(4294967295));
 assertEquals(0, toInt32(4294967296));
 assertEquals(1, toInt32(4294967297));
 
 assertEquals(-2147483647, toInt32(-2147483647));
@@ skipping 16 matching lines @@
 
 assertEquals(-2147483648, toInt32(-2147483648.25));
 assertEquals(-2147483648, toInt32(-2147483648.5));
 assertEquals(-2147483648, toInt32(-2147483648.75));
 assertEquals(1, toInt32(-4294967295.25));
 assertEquals(1, toInt32(-4294967295.5));
 assertEquals(1, toInt32(-4294967295.75));
 assertEquals(1294967296, toInt32(-3000000000.25));
 assertEquals(1294967296, toInt32(-3000000000.5));
 assertEquals(1294967296, toInt32(-3000000000.75));
+
+var base = Math.pow(2, 64);
+assertEquals(0, toInt32(base + 0));
+assertEquals(0, toInt32(base + 1117));
+assertEquals(4096, toInt32(base + 2234));
+assertEquals(4096, toInt32(base + 3351));
+assertEquals(4096, toInt32(base + 4468));
+assertEquals(4096, toInt32(base + 5585));
+assertEquals(8192, toInt32(base + 6702));
+assertEquals(8192, toInt32(base + 7819));
+assertEquals(8192, toInt32(base + 8936));
+assertEquals(8192, toInt32(base + 10053));
+assertEquals(12288, toInt32(base + 11170));
+assertEquals(12288, toInt32(base + 12287));
+assertEquals(12288, toInt32(base + 13404));
+assertEquals(16384, toInt32(base + 14521));
+assertEquals(16384, toInt32(base + 15638));
+assertEquals(16384, toInt32(base + 16755));
+assertEquals(16384, toInt32(base + 17872));
+assertEquals(20480, toInt32(base + 18989));
+assertEquals(20480, toInt32(base + 20106));
+assertEquals(20480, toInt32(base + 21223));
+assertEquals(20480, toInt32(base + 22340));
+assertEquals(24576, toInt32(base + 23457));
+assertEquals(24576, toInt32(base + 24574));
+assertEquals(24576, toInt32(base + 25691));
+assertEquals(28672, toInt32(base + 26808));
+assertEquals(28672, toInt32(base + 27925));
+assertEquals(28672, toInt32(base + 29042));
+assertEquals(28672, toInt32(base + 30159));
+assertEquals(32768, toInt32(base + 31276));