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 /* Test undoing addition in overflow paths when under heavy register pressure. */

 function add1(x, y, a, b, res) { var nres = res + 0; var z = (x + a) + (y + b); assertEq(z, nres); }

 function add2(x, y, a, b, res) { var nres = res + 0; var z = (x + a) + (y + b); assertEq(z, nres); }

 function add3(x, y, a, b, res) { var nres = res + 0; var z = (x + a) + (y + b); assertEq(z, nres); }

 add1(0x7ffffff0, 100, 0, 0, 2147483732);

 add2(-1000, -0x80000000, 0, 0, -2147484648);

 add3(-0x80000000, -1000, 0, 0, -2147484648);

 function cadd1(x, a, b, res) {

   var nres = res + 0;

   var nb = b + 0;

   var z = (x + a) + 1000;

   assertEq(z, nres + nb);

 }

 cadd1(0x7ffffff0, 0, 0, 2147484632);

 function cadd2(x, a, b, res) {

   var nres = res + 0;

   var nb = b + 0;

   var z = (x + a) + (-0x80000000);

   assertEq(z, nres + nb);

 }

 cadd2(-1000, 0, 0, -2147484648);