v8/test/mjsunit/compiler/load-elimination-osr.js

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// Flags: --allow-natives-syntax --load-elimination

// Test global load elimination in the presence of OSR compilation.

function It(x, y) { }

function foo_osr(x, limit) {
  var o = new It();
  o.x = x;
  o.y = x;
  for (var i = 0; i < limit; i++) {
    o.y += o.x;  // Load of x cannot be hoisted due to OSR.
  }

  return o.y;
}

assertEquals(22, foo_osr(11, 1));
assertEquals(24, foo_osr(12, 1));
assertEquals(1300013, foo_osr(13, 100000));


function foo_hot(x, limit) {
  var o = new It();
  o.x = x;
  o.y = x;
  for (var i = 0; i < limit; i++) {
    o.y += o.x;  // Load of x can be hoisted without OSR.
  }

  return o.y;
}

%PrepareFunctionForOptimization(foo_hot);
assertEquals(22, foo_hot(11, 1));
assertEquals(24, foo_hot(12, 1));
%OptimizeFunctionOnNextCall(foo_hot);
assertEquals(32, foo_hot(16, 1));
assertEquals(1300013, foo_hot(13, 100000));