v8/test/mjsunit/regress/wasm/regress-1111522.js
Ng Zhi An e3caf3f524 [wasm-simd] Add regression test for i64x2.shr_s bug
This test uses a i64x2.shr_s to shift a v128 with all bits set by 1,
resulting in v128 with all bits set (no change). This value is then
dropped, and param[2] (3), is returned.

Without the fix, -1 is returned, since i64x2.shr_s overwrites the
register for param[2] with 0xffffffff.

Bug: v8:10752
Bug: chromium:1111522
Change-Id: I0310bf6039be780a6738689069cdbcfa3a24bbdb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2335779
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69233}
2020-08-04 17:51:45 +00:00

27 lines
1.0 KiB
JavaScript

// 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.
// Flags: --experimental-wasm-simd
load('test/mjsunit/wasm/wasm-module-builder.js');
// Regression test to exercise Liftoff's i64x2.shr_s codegen, which back up rcx
// to a scratch register, and immediately overwrote the backup, then later
// restoring the incorrect value. See https://crbug.com/v8/10752 and
// https://crbug.com/1111522 for more.
const builder = new WasmModuleBuilder();
// i64x2.shr_s shifts a v128 (with all bits set), by 1, then drops the result.
// The function returns param 2, which should be unmodified.
builder.addFunction(undefined, kSig_i_iii).addBodyWithEnd([
kSimdPrefix, kExprS128Const, ...new Array(16).fill(0xff),
kExprI32Const, 0x01,
kSimdPrefix, kExprI64x2ShrS, 0x01,
kExprDrop,
kExprLocalGet, 0x02,
kExprEnd,
]);
builder.addExport('main', 0);
const instance = builder.instantiate();
assertEquals(3, instance.exports.main(1, 2, 3));