From: Sunil Pandey <skpgkp2@gmail.com>
To: Noah Goldstein <goldstein.w.n@gmail.com>,
Libc-stable Mailing List <libc-stable@sourceware.org>
Cc: "H.J. Lu" <hjl.tools@gmail.com>,
GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH] x86-64: Fix SSE2 memcmp and SSSE3 memmove for x32
Date: Thu, 12 May 2022 13:12:15 -0700 [thread overview]
Message-ID: <CAMAf5_d0oAqcOCq=ysjqMH9V6Tsbh+AQx7JbXP1j_ShDhPUeKA@mail.gmail.com> (raw)
In-Reply-To: <CAFUsyfKkX-GGqs18SM9rhhqCihkge43T5LN0+pD1wBHEqekBWw@mail.gmail.com>
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On Fri, Apr 22, 2022 at 11:07 AM Noah Goldstein via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> On Fri, Apr 22, 2022 at 12:58 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > Clear the upper 32 bits in RDX (memory size) for x32 to fix
> >
> > FAIL: string/tst-size_t-memcmp
> > FAIL: string/tst-size_t-memcmp-2
> > FAIL: string/tst-size_t-memcpy
> > FAIL: wcsmbs/tst-size_t-wmemcmp
> >
> > on x32 introduced by
> >
> > 8804157ad9 x86: Optimize memcmp SSE2 in memcmp.S
> > 26b2478322 x86: Reduce code size of mem{move|pcpy|cpy}-ssse3
> > ---
> > sysdeps/x86_64/memcmp.S | 4 ++++
> > sysdeps/x86_64/multiarch/memmove-ssse3.S | 4 ++++
> > 2 files changed, 8 insertions(+)
> >
> > diff --git a/sysdeps/x86_64/memcmp.S b/sysdeps/x86_64/memcmp.S
> > index b153694048..5718a7da86 100644
> > --- a/sysdeps/x86_64/memcmp.S
> > +++ b/sysdeps/x86_64/memcmp.S
> > @@ -46,6 +46,10 @@
> >
> > .text
> > ENTRY(MEMCMP)
> > +# ifdef __ILP32__
> > + /* Clear the upper 32 bits. */
> > + movl %edx, %edx
> > +# endif
> > #ifdef USE_AS_WMEMCMP
> > /* Use 0xffff to test for mismatches on pmovmskb bitmask. Store
> > in ecx for code size. This is preferable to using `incw` as
> > diff --git a/sysdeps/x86_64/multiarch/memmove-ssse3.S b/sysdeps/x86_64/multiarch/memmove-ssse3.S
> > index 215583e7bd..310ff62b86 100644
> > --- a/sysdeps/x86_64/multiarch/memmove-ssse3.S
> > +++ b/sysdeps/x86_64/multiarch/memmove-ssse3.S
> > @@ -27,6 +27,10 @@ ENTRY(MEMMOVE_CHK)
> > END(MEMMOVE_CHK)
> >
> > ENTRY_P2ALIGN(MEMMOVE, 6)
> > +# ifdef __ILP32__
> > + /* Clear the upper 32 bits. */
> > + movl %edx, %edx
> > +# endif
> > movq %rdi, %rax
> > L(start):
> > cmpq $16, %rdx
> > --
> > 2.35.1
> >
>
> LGTM.
I would like to backport this patch to release branches.
Any comments or objections?
Conflict resolution patch attached.
--Sunil
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From 6e37b24194e2361b513a49ab92a686956f1cbeac Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Fri, 22 Apr 2022 10:53:13 -0700
Subject: [PATCH 23/26] x86-64: Fix SSE2 memcmp and SSSE3 memmove for x32
Clear the upper 32 bits in RDX (memory size) for x32 to fix
FAIL: string/tst-size_t-memcmp
FAIL: string/tst-size_t-memcmp-2
FAIL: string/tst-size_t-memcpy
FAIL: wcsmbs/tst-size_t-wmemcmp
on x32 introduced by
8804157ad9 x86: Optimize memcmp SSE2 in memcmp.S
26b2478322 x86: Reduce code size of mem{move|pcpy|cpy}-ssse3
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
(cherry picked from commit 8ea20ee5f6145de4bff9481d3e09ac36ba9df8f3)
---
sysdeps/x86_64/memcmp.S | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/sysdeps/x86_64/memcmp.S b/sysdeps/x86_64/memcmp.S
index b153694048..5718a7da86 100644
--- a/sysdeps/x86_64/memcmp.S
+++ b/sysdeps/x86_64/memcmp.S
@@ -46,6 +46,10 @@
.text
ENTRY(MEMCMP)
+# ifdef __ILP32__
+ /* Clear the upper 32 bits. */
+ movl %edx, %edx
+# endif
#ifdef USE_AS_WMEMCMP
/* Use 0xffff to test for mismatches on pmovmskb bitmask. Store
in ecx for code size. This is preferable to using `incw` as
--
2.35.1
parent reply other threads:[~2022-05-12 20:12 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <CAFUsyfKkX-GGqs18SM9rhhqCihkge43T5LN0+pD1wBHEqekBWw@mail.gmail.com>]
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