From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by sourceware.org (Postfix) with ESMTPS id CA0E53858D3C for ; Thu, 24 Mar 2022 21:43:43 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CA0E53858D3C Received: by mail-pj1-x1033.google.com with SMTP id o3-20020a17090a3d4300b001c6bc749227so6430924pjf.1 for ; Thu, 24 Mar 2022 14:43:43 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=v5NJdSSG4NcL80iPyJqUE5qYBC59EpuVHRLXyVj7aoQ=; b=tVqwxiI5t3WmgCJoN/EqUx+vyUvyLUyO6x7ASoT6IyOwOOYkULCR0pW1W+EEpfNd9b /X2Rw1cZAac/MV1MT+ofi2574a9cWvHPzuTerRc3vXx1P1C08Tn65dcjVbBS9CykaGkh Z7oHuYrbMflNejnOzMtnujdNcpxNglcsQZPxWNvWnTTM+opYYytTnal3gSwvf9Ivh70w 0KQxoDodXUzKqmiNSsYKLpWNMC6Jvjo+i0QB5p3P0DlIRN+WmWnIrXdJaJKYGnRI3pP1 bpBYXeiztoViueqzjfgBjL3WkYrOK+IA/kXqm6DOlxX7p3F5LaNCyWvBMYr/KFQ/OT5C 2erQ== X-Gm-Message-State: AOAM530RnlUIf+8hQABiqHPsw+rMA0SnQZfwyySfqt0oEvjOdjNdJoOn C6hJSz77xfZKM6yYWYfOqdsdszi9erI6AiO/o/pvSgZ4 X-Google-Smtp-Source: ABdhPJyovp1zpO6VAJK/Whw6ZwRAWSBdS3WCM56PhUngILE3WpRlqUhfWvJRDpB2UsZegTQEkhb/uXmg0masjQErA/E= X-Received: by 2002:a17:90b:4c44:b0:1c7:1326:ec90 with SMTP id np4-20020a17090b4c4400b001c71326ec90mr20579800pjb.87.1648158222845; Thu, 24 Mar 2022 14:43:42 -0700 (PDT) MIME-Version: 1.0 References: <20220323215734.3927131-12-goldstein.w.n@gmail.com> <20220324205033.3274646-1-goldstein.w.n@gmail.com> In-Reply-To: From: Noah Goldstein Date: Thu, 24 Mar 2022 16:43:32 -0500 Message-ID: Subject: Re: [PATCH v2 12/31] x86: Fix fallback for wcsncmp_avx2 in strcmp-avx2.S [BZ #28896] To: "H.J. Lu" Cc: GNU C Library , "Carlos O'Donell" Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-9.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Mar 2022 21:43:45 -0000 On Thu, Mar 24, 2022 at 4:26 PM H.J. Lu wrote: > > On Thu, Mar 24, 2022 at 1:50 PM Noah Goldstein wrote: > > > > Overflow case for __wcsncmp_avx2_rtm should be __wcscmp_avx2_rtm not > > __wcscmp_avx2. > > > > commit ddf0992cf57a93200e0c782e2a94d0733a5a0b87 > > Author: Noah Goldstein > > Date: Sun Jan 9 16:02:21 2022 -0600 > > > > x86: Fix __wcsncmp_avx2 in strcmp-avx2.S [BZ# 28755] > > > > Set the wrong fallback function for `__wcsncmp_avx2_rtm`. It was set > > to fallback on to `__wcscmp_avx2` instead of `__wcscmp_avx2_rtm` which > > can cause spurious aborts. > > > > This change will need to be backported. > > > > All string/memory tests pass. > > --- > > sysdeps/x86/tst-strncmp-rtm.c | 15 +++++++++++++++ > > sysdeps/x86_64/multiarch/strcmp-avx2.S | 2 +- > > 2 files changed, 16 insertions(+), 1 deletion(-) > > > > diff --git a/sysdeps/x86/tst-strncmp-rtm.c b/sysdeps/x86/tst-strncmp-rtm.c > > index 300bc8c281..a3b14e72ff 100644 > > --- a/sysdeps/x86/tst-strncmp-rtm.c > > +++ b/sysdeps/x86/tst-strncmp-rtm.c > > @@ -70,6 +70,16 @@ function_overflow (void) > > return 1; > > } > > > > +__attribute__ ((noinline, noclone)) > > +static int > > +function_overflow2 (void) > > +{ > > + if (STRNCMP (string1, string2, SIZE_MAX >> 4) == 0) > > + return 0; > > + else > > + return 1; > > +} > > + > > static int > > do_test (void) > > { > > @@ -77,5 +87,10 @@ do_test (void) > > if (status != EXIT_SUCCESS) > > return status; > > status = do_test_1 (TEST_NAME, LOOP, prepare, function_overflow); > > + if (status != EXIT_SUCCESS) > > + return status; > > + status = do_test_1 (TEST_NAME, LOOP, prepare, function_overflow2); > > + if (status != EXIT_SUCCESS) > > + return status; > > return status; > > } > > diff --git a/sysdeps/x86_64/multiarch/strcmp-avx2.S b/sysdeps/x86_64/multiarch/strcmp-avx2.S > > index 52ff5ad724..86a86b68e3 100644 > > --- a/sysdeps/x86_64/multiarch/strcmp-avx2.S > > +++ b/sysdeps/x86_64/multiarch/strcmp-avx2.S > > @@ -122,7 +122,7 @@ ENTRY(STRCMP) > > are cases where length is large enough that it can never be a > > bound on valid memory so just use wcscmp. */ > > shrq $56, %rcx > > - jnz __wcscmp_avx2 > > + jnz OVERFLOW_STRCMP > > > > leaq (, %rdx, 4), %rdx > > # endif > > -- > > 2.25.1 > > > > LGTM. Verified on AVX2 machine with RTM. Without the fix, > the new testcase failed. And that w/ the fix it passes? > > Reviewed-by: H.J. Lu > > Thanks. > > -- > H.J.