blob: 00700d73121fdf85f6c7229e7e56c323219063f4 [file] [log] [blame]
// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// @dart = 2.9
// Regression test for dart2js, whose value range analysis phase
// assumed loop phis that were integer necessarily had integer inputs.
var array = const [0, 0.5];
var globalB = array[0];
var otherArray = [5];
main() {
var b = globalB;
var a = b + 1;
if (otherArray[0] == 0) {
// Use a non-existing selector to prevent adding a bailout check.
(a as dynamic).noSuch();
a = otherArray[0];
}
// Use [a] to make sure it does not become dead code.
var f = array[a];
// Add an integer check on [b].
var d = array[b];
// This instruction will be GVN to the same value as [a].
// By being GVN'ed, [e] will have its type changed from integer
// to number: because of the int type check on [b], we know
// [: b + 1 :] returns an integer.
// However we update this instruction with the previous [: b + 1 :]
// that did not have that information and therefore only knows that
// the instruction returns a number.
var e = b + 1;
// Introduce a loop phi that has [e] as header input, and [e++] as
// update input. By having [e] as input, dart2js will compute an
// integer type for the phi. However, after GVN, [e] becomes a
// number.
while (otherArray[0] == 0) {
// Use [e] as an index for an array so that the value range
// analysis tries to compute a range for [e].
otherArray[e] = d + f;
e++;
}
}