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[turbofan] Avoid relaxing node that has other effect use

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It is related to Reduce consecutive overflow addition with constants.
Turned out that we needs to consider also effect use before relaxing it.

This fixed the issue that fuzzer found in e93a369f7a.

Bug: chromium:1137586
Change-Id: I32fee5ecc7a6ce40d6f739f9c6e2440a647a2222
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2469597
Commit-Queue: Z Nguyen-Huu <duongn@microsoft.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70514}
This commit is contained in:
Z Nguyen-Huu 2020-10-14 11:11:50 -07:00 committed by Commit Bot
parent 04221a96a3
commit b22f5ac6e7
2 changed files with 20 additions and 6 deletions
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10
src/compiler/simplified-operator-reducer.cc
View File

@ -234,16 +234,14 @@ Reduction SimplifiedOperatorReducer::Reduce(Node* node) {
bool overflow = base::bits::SignedAddOverflow32(
n.right().Value(), m.right().Value(), &val);
if (!overflow) {
bool has_no_other_value_uses = true;
bool has_no_other_uses = true;
for (Edge edge : checked_int32_add->use_edges()) {
if (!edge.from()->IsDead() &&
!NodeProperties::IsEffectEdge(edge) &&
edge.from() != node) {
has_no_other_value_uses = false;
if (!edge.from()->IsDead() && edge.from() != node) {
has_no_other_uses = false;
break;
}
}
if (has_no_other_value_uses) {
if (has_no_other_uses) {
node->ReplaceInput(0, n.left().node());
node->ReplaceInput(1, jsgraph()->Int32Constant(val));
RelaxEffectsAndControls(checked_int32_add);

16
test/mjsunit/regress/regress-crbug-1137586.js Normal file
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@ -0,0 +1,16 @@
// Copyright 2020 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.
function f() {
for (var i = 0; i < 100000; i++) {
var a = arguments[0] + 2;
var b = arguments[1] + 2;
var c = a + i + 5;
var d = c + 3;
}
}
for (var j = 0; j < 3; j++) {
f(2, 3);
}