blob: 59212add5138255cc76c2665c3c84a3fe34ebb93 [file] [log] [blame]
// Copyright (c) 2020, 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.
//
// This test checks that late constant folding passes don't violate
// representation requirements for uses of a definition that is being
// folded away.
import 'dart:ffi';
import 'package:expect/expect.dart';
import 'package:ffi/ffi.dart';
class X {
int field;
X(this.field);
}
@pragma('vm:never-inline')
int loadFrom(Pointer<Int32> p) {
final x = X(0);
x.field = 1;
if ((x.field + 1) == 2) {
x.field = 0;
}
// The code above tries to delay folding of x.field into a constant
// until later passes. Inside p[...] there will be an unboxed Int64
// arithmetic used to compute an index which will get constant folded
// as soon as x.field is constant folded. CP should insert unboxed constant
// or an unbox of a constant as a result of constant folding. If it does
// not - then we will get an incorrect graph where a tagged value is flowing
// into a LoadIndexed instruction without a deopt-id.
return p[x.field];
}
void main() {
final p = calloc<Int32>(128);
p[0] = 42;
Expect.equals(42, loadFrom(p));
calloc.free(p);
}