v8/test/mjsunit/regress/wasm/regress-1272204.js
Clemens Backes 10bbbf13a2 [compiler] Fix mixed same-as-input and unique registers
The mid-tier register allocator could not handle the case that the same
virtual register was used for
- the input corresponding to the 'same-as-input' output, and
- another 'unique register' input.

In this case, it cannot choose the already assigned register for the
'unique' register. Instead, it needs to allocate a new register and
introduce a gap move to duplicate the input value in two different
registers.

FYI, the instruction where the current logic failed was:
  (v5(0), v6(R)) = IA32AddPair v7(R) v7(*) v8(R) v7(R)
(where the last input was marked 'unique').

R=leszeks@chromium.org
CC=thibaudm@chromium.org

Bug: v8:12330, chromium:1272204
Change-Id: Ie4843aa9f5e027afe503e0481a4acdfa325dfe0e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3347821
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78411}
2021-12-20 12:58:23 +00:00

20 lines
660 B
JavaScript

// Copyright 2021 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: --no-liftoff --turbo-force-mid-tier-regalloc
d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
const builder = new WasmModuleBuilder();
builder.addMemory(16, 32, false);
builder.addFunction(undefined, kSig_i_iii).addBody([
kExprI64Const, 0x7a, // i64.const
kExprI64Const, 0x7f, // i64.const
kExprI64Const, 0x7e, // i64.const
kExprI64Add, // i64.add
kExprI64DivS, // i64.div_s
kExprUnreachable, // unreachable
]);
builder.toModule();