v8/test/mjsunit/optimized-foreach.js

// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Flags: --allow-natives-syntax --expose-gc --turbo-inline-array-builtins

var a = [
  0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13,
  14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 0,  0
];
var b = [
  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13,
  14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25
];
var c = [
  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13,
  14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25
];

// Unknown field access leads to soft-deopt unrelated to forEach, should still
// lead to correct result.
(function() {
var result = 0;
var eagerDeoptInCalled = function(deopt) {
  var sum = function(v, i, o) {
    result += v;
    if (i == 13 && deopt) {
      a.abc = 25;
    }
  };
  a.forEach(sum);
};
%PrepareFunctionForOptimization(eagerDeoptInCalled);
eagerDeoptInCalled();
eagerDeoptInCalled();
%OptimizeFunctionOnNextCall(eagerDeoptInCalled);
eagerDeoptInCalled();
eagerDeoptInCalled(true);
eagerDeoptInCalled();
assertEquals(1500, result);
})();

// Length change detected during loop, must cause properly handled eager deopt.
(function() {
var result = 0;
var eagerDeoptInCalled = function(deopt) {
  var sum = function(v, i, o) {
    result += v;
    a.length = i == 13 && deopt ? 25 : 27;
  };
  a.forEach(sum);
};
%PrepareFunctionForOptimization(eagerDeoptInCalled);
eagerDeoptInCalled();
eagerDeoptInCalled();
%OptimizeFunctionOnNextCall(eagerDeoptInCalled);
eagerDeoptInCalled();
eagerDeoptInCalled(true);
eagerDeoptInCalled();
assertEquals(1500, result);
})();

// Escape analyzed array
(function() {
var result = 0;
var eagerDeoptInCalled = function(deopt) {
  var a_noescape = [0, 1, 2, 3, 4, 5];
  var sum = function(v, i, o) {
    result += v;
    if (i == 13 && deopt) {
      a_noescape.length = 25;
    }
  };
  a_noescape.forEach(sum);
};
%PrepareFunctionForOptimization(eagerDeoptInCalled);
eagerDeoptInCalled();
eagerDeoptInCalled();
%OptimizeFunctionOnNextCall(eagerDeoptInCalled);
eagerDeoptInCalled();
eagerDeoptInCalled(true);
eagerDeoptInCalled();
assertEquals(75, result);
})();

// Escape analyzed array where sum function isn't inlined, forcing a lazy deopt
// with GC that relies on the stashed-away return result fro the lazy deopt
// being properly stored in a place on the stack that gets GC'ed.
(function() {
var result = 0;
var lazyDeopt = function(deopt) {
  var b = [1, 2, 3];
  var sum = function(v, i, o) {
    result += i;
    if (i == 1 && deopt) {
      %DeoptimizeFunction(lazyDeopt);
    }
    gc();
    gc();
  };
  %NeverOptimizeFunction(sum);
  b.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
lazyDeopt(true);
lazyDeopt();
})();

// Lazy deopt from runtime call from inlined callback function.
(function() {
var result = 0;
var lazyDeopt = function(deopt) {
  var sum = function(v, i, o) {
    result += i;
    if (i == 13 && deopt) {
      %DeoptimizeNow();
    }
  };
  b.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
lazyDeopt(true);
lazyDeopt();
assertEquals(1500, result);
})();

// Lazy deopt from runtime call from non-inline callback function.
(function() {
var result = 0;
var lazyDeopt = function(deopt) {
  var sum = function(v, i, o) {
    result += i;
    if (i == 13 && deopt) {
      %DeoptimizeNow();
    }
  };
  %NeverOptimizeFunction(sum);
  b.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
lazyDeopt(true);
lazyDeopt();
assertEquals(1500, result);
})();

(function() {
var result = 0;
var lazyDeopt = function(deopt) {
  var sum = function(v, i, o) {
    result += i;
    if (i == 13 && deopt) {
      %DeoptimizeNow();
      gc();
      gc();
      gc();
    }
  };
  c.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
lazyDeopt(true);
lazyDeopt();
assertEquals(1500, result);
})();

// Call to a.forEach is done inside a try-catch block and the callback function
// being called actually throws.
(function() {
var caught = false;
var result = 0;
var lazyDeopt = function(deopt) {
  var sum = function(v, i, o) {
    result += i;
    if (i == 1 && deopt) {
      throw 'a';
    }
  };
  try {
    c.forEach(sum);
  } catch (e) {
    caught = true;
  }
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
assertDoesNotThrow(lazyDeopt.bind(this, true));
assertTrue(caught);
lazyDeopt();
})();

// Call to a.forEach is done inside a try-catch block and the callback function
// being called actually throws, but the callback is not inlined.
(function() {
var caught = false;
var result = 0;
var lazyDeopt = function(deopt) {
  var sum = function(v, i, o) {
    result += i;
    if (i == 1 && deopt) {
      throw 'a';
    }
  };
  %NeverOptimizeFunction(sum);
  try {
    c.forEach(sum);
  } catch (e) {
    caught = true;
  }
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
assertDoesNotThrow(lazyDeopt.bind(this, true));
assertTrue(caught);
lazyDeopt();
})();

// Call to a.forEach is done inside a try-catch block and the callback function
// being called throws into a deoptimized caller function.
(function TestThrowIntoDeoptimizedOuter() {
  var a = [1, 2, 3, 4];
  var lazyDeopt = function(deopt) {
    var sum = function(v, i, o) {
      result += v;
      if (i == 1 && deopt) {
        %DeoptimizeFunction(lazyDeopt);
        throw "some exception";
      }
    };
    %NeverOptimizeFunction(sum);
    var result = 0;
    try {
      a.forEach(sum);
    } catch (e) {
      assertEquals('some exception', e);
      result += 100;
    }
    return result;
  };
  ;
  %PrepareFunctionForOptimization(lazyDeopt);
  assertEquals(10, lazyDeopt(false));
  assertEquals(10, lazyDeopt(false));
  assertEquals(103, lazyDeopt(true));
  assertEquals(103, lazyDeopt(true));
  %OptimizeFunctionOnNextCall(lazyDeopt);
  assertEquals(10, lazyDeopt(false));
  assertEquals(103, lazyDeopt(true));
})();

(function() {
var re = /Array\.forEach/;
var lazyDeopt = function foobar(deopt) {
  var b = [1, 2, 3];
  var result = 0;
  var sum = function(v, i, o) {
    result += v;
    if (i == 1) {
      var e = new Error();
      assertTrue(re.exec(e.stack) !== null);
    }
  };
  var o = [1, 2, 3];
  b.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
})();

(function() {
var re = /Array\.forEach/;
var lazyDeopt = function(deopt) {
  var b = [1, 2, 3];
  var result = 0;
  var sum = function(v, i, o) {
    result += v;
    if (i == 1) {
      var e = new Error();
      assertTrue(re.exec(e.stack) !== null);
    }
  };
  %NeverOptimizeFunction(sum);
  var o = [1, 2, 3];
  b.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
})();

(function() {
var re = /Array\.forEach/;
var lazyDeopt = function(deopt) {
  var b = [1, 2, 3];
  var result = 0;
  var sum = function(v, i, o) {
    result += v;
    if (i == 1) {
      %DeoptimizeNow();
    } else if (i == 2) {
      var e = new Error();
      assertTrue(re.exec(e.stack) !== null);
    }
  };
  var o = [1, 2, 3];
  b.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
lazyDeopt();
lazyDeopt();
%OptimizeFunctionOnNextCall(lazyDeopt);
lazyDeopt();
})();

(function() {
var re = /Array\.forEach/;
var a = [1, 2, 3];
var result = 0;
var lazyDeopt = function() {
  var sum = function(v, i, o) {
    result += i;
    if (i == 1) {
      %DeoptimizeFunction(lazyDeopt);
      throw new Error();
    }
  };
  a.forEach(sum);
};
%PrepareFunctionForOptimization(lazyDeopt);
assertThrows(() => lazyDeopt());
assertThrows(() => lazyDeopt());
try {
  lazyDeopt();
} catch (e) {
  assertTrue(re.exec(e.stack) !== null);
}
%OptimizeFunctionOnNextCall(lazyDeopt);
try {
  lazyDeopt();
} catch (e) {
  assertTrue(re.exec(e.stack) !== null);
}
})();

// Verify holes are skipped.
(() => {
  const a = [1, 2, , 3, 4];
  function withHoles() {
    const callback_values = [];
    a.forEach(v => {
      callback_values.push(v);
    });
    return callback_values;
  };
  %PrepareFunctionForOptimization(withHoles);
  withHoles();
  withHoles();
  %OptimizeFunctionOnNextCall(withHoles);
  assertArrayEquals([1, 2, 3, 4], withHoles());
})();

(() => {
  const a = [1.5, 2.5, , 3.5, 4.5];
  function withHoles() {
    const callback_values = [];
    a.forEach(v => {
      callback_values.push(v);
    });
    return callback_values;
  };
  %PrepareFunctionForOptimization(withHoles);
  withHoles();
  withHoles();
  %OptimizeFunctionOnNextCall(withHoles);
  assertArrayEquals([1.5, 2.5, 3.5, 4.5], withHoles());
})();

// Ensure that we handle side-effects between load and call.
(() => {
  function side_effect(a, b) {
    if (b) a.foo = 3;
    return a;
  }
  %NeverOptimizeFunction(side_effect);

  function unreliable(a, b) {
    let sum = 0;
    return a.forEach(x => sum += x, side_effect(a, b));
  };
  %PrepareFunctionForOptimization(unreliable);
  let a = [1, 2, 3];
  unreliable(a, false);
  unreliable(a, false);
  %OptimizeFunctionOnNextCall(unreliable);
  unreliable(a, false);
  // Now actually do change the map.
  unreliable(a, true);
})();