// 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
// Flags: --opt --no-always-opt --no-lazy-feedback-allocation

// TODO(v8:10195): Fix these tests s.t. we assert deoptimization occurs when
// expected (e.g. in a %DeoptimizeNow call), then remove
// --no-lazy-feedback-allocation.

// Unknown field access leads to soft-deopt unrelated to filter, should still
// lead to correct result.
(function() {
  var a = [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 result = 0;
  var eagerDeoptInCalled = function(deopt) {
    var callback = function(v,i,o) {
      if (i == 13 && deopt) {
        a.abc = 25;
      }

      // Ensure that the output array is smaller by shaving off the first
      // item.
      if (i === 0) return false;
      result += v;
      return true;
    }
    return a.filter(callback);
  };
  %PrepareFunctionForOptimization(eagerDeoptInCalled);
  eagerDeoptInCalled();
  eagerDeoptInCalled();
  %OptimizeFunctionOnNextCall(eagerDeoptInCalled);
  eagerDeoptInCalled();
  var deopt_result = eagerDeoptInCalled(true);
  assertEquals(a.slice(1), deopt_result);
  eagerDeoptInCalled();
  assertEquals(1620, result);
})();

// Length change detected during loop, must cause properly handled eager deopt.
(function() {
  var eagerDeoptInCalled = function(deopt) {
    var a = [1,2,3,4,5,6,7,8,9,10];
    var callback = function(v,i,o) {
      a.length = (i == 5 && deopt) ? 8 : 10;
      return i == 0 ? false : true;
    }
    return a.filter(callback);
  };
  %PrepareFunctionForOptimization(eagerDeoptInCalled);
  var like_a = [1,2,3,4,5,6,7,8,9,10];
  assertEquals(like_a.slice(1), eagerDeoptInCalled());
  eagerDeoptInCalled();
  %OptimizeFunctionOnNextCall(eagerDeoptInCalled);
  assertEquals(like_a.slice(1), eagerDeoptInCalled());
  assertEquals(like_a.slice(1).slice(0, 7), eagerDeoptInCalled(true));
  eagerDeoptInCalled();
})();

// Lazy deopt from a callback that changes the input array. Ensure that
// the value stored in the output array is from the original read.
(function() {
  var a = [1, 2, 3, 4, 5];
  var lazyChanger = function(deopt) {
    var callback = function(v,i,o) {
      if (i === 2 && deopt) {
        a[2] = 100;
        %DeoptimizeNow();
       }
      return true;
    }
    return a.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyChanger);
  assertEquals(a, lazyChanger());
  lazyChanger();
  %OptimizeFunctionOnNextCall(lazyChanger);
  var deopt_result = lazyChanger(true);
  assertEquals([1, 2, 3, 4, 5], deopt_result);
  assertEquals([1, 2, 100, 4, 5], lazyChanger());
})();

// Lazy deopt from a callback that returns false at the deopt point.
// Ensure the non-selection is respected in the output array.
(function() {
  var a = [1, 2, 3, 4, 5];
  var lazyDeselection = function(deopt) {
    var callback = function(v,i,o) {
      if (i === 2 && deopt) {
        %DeoptimizeNow();
        return false;
       }
      return true;
    }
    return a.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyDeselection);
  assertEquals(a, lazyDeselection());
  lazyDeselection();
  %OptimizeFunctionOnNextCall(lazyDeselection);
  var deopt_result = lazyDeselection(true);
  assertEquals([1, 2, 4, 5], deopt_result);
  assertEquals([1, 2, 3, 4, 5], lazyDeselection());
})();


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

// Escape analyzed array where callback 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 callback = function(v,i,o) {
      result += i;
      if (i == 1 && deopt) {
        %DeoptimizeFunction(lazyDeopt);
      }
      gc(); gc();
      return true;
    };
    %NeverOptimizeFunction(callback);
    b.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  lazyDeopt();
  lazyDeopt();
  %OptimizeFunctionOnNextCall(lazyDeopt);
  lazyDeopt();
  lazyDeopt(true);
  lazyDeopt();
})();

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

(function() {
  var a = [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 result = 0;
  var lazyDeopt = function(deopt) {
    var callback = function(v,i,o) {
      result += i;
      if (i == 13 && deopt) {
          %DeoptimizeNow();
          gc();
          gc();
          gc();
      }
      return true;
    }
    a.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  lazyDeopt();
  lazyDeopt();
  %OptimizeFunctionOnNextCall(lazyDeopt);
  lazyDeopt();
  lazyDeopt(true);
  lazyDeopt();
  assertEquals(1500, result);
})();

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

// Call to a.filter is done inside a try-catch block and the callback function
// being called actually throws, but the callback is not inlined.
(function() {
  var a = [1,2,3,4,5,6,7,8,9,10];
  var caught = false;
  var result = 0;
  var lazyDeopt = function(deopt) {
    var callback = function(v,i,o) {
      result += i;
      if (i == 1 && deopt) {
        throw("a");
      }
      return true;
    };
    %NeverOptimizeFunction(callback);
    try {
      a.filter(callback);
    } catch (e) {
      caught = true;
    }
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  lazyDeopt();
  lazyDeopt();
  %OptimizeFunctionOnNextCall(lazyDeopt);
  lazyDeopt();
  assertDoesNotThrow(() => lazyDeopt(true));
  assertTrue(caught);
  lazyDeopt();
})();

// Call to a.filter 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 callback = function(v,i,o) {
      if (i == 1 && deopt) {
        %DeoptimizeFunction(lazyDeopt);
        throw "some exception";
      }
      return true;
    };
    %NeverOptimizeFunction(callback);
    var result = 0;
    try {
      result = a.filter(callback);
    } catch (e) {
      assertEquals("some exception", e)
      result = "nope";
    }
    return result;
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  assertEquals([1,2,3,4], lazyDeopt(false));
  assertEquals([1,2,3,4], lazyDeopt(false));
  assertEquals("nope", lazyDeopt(true));
  assertEquals("nope", lazyDeopt(true));
  %OptimizeFunctionOnNextCall(lazyDeopt);
  assertEquals([1,2,3,4], lazyDeopt(false));
  assertEquals("nope", lazyDeopt(true));
})();

// An error generated inside the callback includes filter in it's
// stack trace.
(function() {
  var re = /Array\.filter/;
  var lazyDeopt = function(deopt) {
    var b = [1,2,3];
    var result = 0;
    var callback = function(v,i,o) {
      result += v;
      if (i == 1) {
        var e = new Error();
        assertTrue(re.exec(e.stack) !== null);
      }
      return true;
    };
    var o = [1,2,3];
    b.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  lazyDeopt();
  lazyDeopt();
  %OptimizeFunctionOnNextCall(lazyDeopt);
  lazyDeopt();
})();

// An error generated inside a non-inlined callback function also
// includes filter in it's stack trace.
(function() {
  var re = /Array\.filter/;
  var lazyDeopt = function(deopt) {
    var b = [1,2,3];
    var result = 0;
    var callback = function(v,i,o) {
      result += v;
      if (i == 1) {
        var e = new Error();
        assertTrue(re.exec(e.stack) !== null);
      }
      return true;
    };
    %NeverOptimizeFunction(callback);
    var o = [1,2,3];
    b.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  lazyDeopt();
  lazyDeopt();
  %OptimizeFunctionOnNextCall(lazyDeopt);
  lazyDeopt();
})();

// An error generated inside a recently deoptimized callback function
// includes filter in it's stack trace.
(function() {
  var re = /Array\.filter/;
  var lazyDeopt = function(deopt) {
    var b = [1,2,3];
    var result = 0;
    var callback = function(v,i,o) {
      result += v;
      if (i == 1) {
        %DeoptimizeNow();
      } else if (i == 2) {
        var e = new Error();
        assertTrue(re.exec(e.stack) !== null);
      }
      return true;
    };
    var o = [1,2,3];
    b.filter(callback);
  };
  %PrepareFunctionForOptimization(lazyDeopt);
  lazyDeopt();
  lazyDeopt();
  %OptimizeFunctionOnNextCall(lazyDeopt);
  lazyDeopt();
})();

// Verify that various exception edges are handled appropriately.
// The thrown Error object should always indicate it was created from
// a filter call stack.
(function() {
  var re = /Array\.filter/;
  var a = [1,2,3];
  var result = 0;
  var lazyDeopt = function() {
    var callback = function(v,i,o) {
      result += i;
      if (i == 1) {
        %DeoptimizeFunction(lazyDeopt);
        throw new Error();
      }
      return true;
    };
    a.filter(callback);
  };
  %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];
  let callback_values = [];
  function withHoles() {
    callback_values = [];
    return a.filter(v => {
      callback_values.push(v);
      return true;
    });
  }
  %PrepareFunctionForOptimization(withHoles);
  withHoles();
  withHoles();
  %OptimizeFunctionOnNextCall(withHoles);
  assertArrayEquals([1, 2, 3, 4], withHoles());
  assertArrayEquals([1, 2, 3, 4], callback_values);
})();

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

// 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) {
    return a.filter(x => x % 2 === 0, 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);
})();

// Messing with the Array species constructor causes deoptimization.
(function() {
  var result = 0;
  var a = [1,2,3];
  var species_breakage = function() {
    var callback = function(v,i,o) {
      result += v;
      return true;
    }
    a.filter(callback);
  };
  %PrepareFunctionForOptimization(species_breakage);
  species_breakage();
  species_breakage();
  %OptimizeFunctionOnNextCall(species_breakage);
  species_breakage();
  a.constructor = {};
  a.constructor[Symbol.species] = function() {};
  species_breakage();
  assertUnoptimized(species_breakage);
  assertEquals(24, result);
})();