Function ShiftTest

deps/v8/test/mjsunit/constant-folding.js:190–220

()

// Some tests of shifts that get into the corners in terms of coverage.
// We generate different code for the case where the operand is a constant.
function ShiftTest() {
  var x = 123;
  assertEquals(x, x >> 0);
  assertEquals(x, x << 0);
  assertEquals(x, x >>> 0);
  assertEquals(61, x >> 1);
  assertEquals(246, x << 1);
  assertEquals(61, x >>> 1);
  x = -123;
  assertEquals(x, x >> 0);
  assertEquals(x, x << 0);
  assertEquals(0x10000 * 0x10000 + x, x >>> 0);
  assertEquals(-62, x >> 1);
  assertEquals(-246, x << 1);
  assertEquals(0x10000 * 0x8000 - 62, x >>> 1);
  // Answer is non-Smi so the subtraction is not folded in the code
  // generator.
  assertEquals(-0x40000001, -0x3fffffff - 2);

  x = 123;
  assertEquals(0, x & 0);

  // Answer is non-smi and lhs of << is a temporary heap number that we can
  // overwrite.
  x = 123.0001;
  assertEquals(1073741824, (x * x) << 30);
  x = 123;
  // Answer is non-smi and lhs of << is a temporary heap number that we think
  // we can overwrite (but we can't because it's a Smi).
  assertEquals(1073741824, (x * x) << 30);
}


test();