From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1791) id 230ED3853519; Fri, 27 Oct 2023 12:30:08 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 230ED3853519 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1698409808; bh=GKQoPsYQW5u12j/2SK6kQ+DYY1cpcDpjQn7Hd8TicdQ=; h=From:To:Subject:Date:From; b=JBEcqhWIc8h3XEkfP6UK7xDuAq94kpnv24U4NFNmDJ6Fu2YcvNqT1tPQrNCYIp8TY 53uVCCqUeOPo4mWsaQdaE8g4uthadNWz5Bag8h4NVgRlKmNwM2tpgdgaru/T9UC9NB d6G6AVik0mlZfAVr6d45oSJrAcL3xR7cXNqNhGEI= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Adhemerval Zanella To: glibc-cvs@sourceware.org Subject: [glibc/azanella/bz30944-memcpy-zen] x86: Expand the comment on when REP STOSB is used on memset X-Act-Checkin: glibc X-Git-Author: Adhemerval Zanella X-Git-Refname: refs/heads/azanella/bz30944-memcpy-zen X-Git-Oldrev: 4c023248ca791eefec5a7553057c0af3b9035f6c X-Git-Newrev: b0fe1533ff7283e765a2e590d210999ca045ca4c Message-Id: <20231027123008.230ED3853519@sourceware.org> Date: Fri, 27 Oct 2023 12:30:08 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b0fe1533ff7283e765a2e590d210999ca045ca4c commit b0fe1533ff7283e765a2e590d210999ca045ca4c Author: Adhemerval Zanella Date: Fri Oct 27 08:14:14 2023 -0300 x86: Expand the comment on when REP STOSB is used on memset Diff: --- sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S index 3d9ad49cb9..0821b32997 100644 --- a/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S +++ b/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S @@ -21,7 +21,9 @@ 2. If size is less than VEC, use integer register stores. 3. If size is from VEC_SIZE to 2 * VEC_SIZE, use 2 VEC stores. 4. If size is from 2 * VEC_SIZE to 4 * VEC_SIZE, use 4 VEC stores. - 5. If size is more to 4 * VEC_SIZE, align to 4 * VEC_SIZE with + 5. On machines ERMS feature, if size is greater or equal than + __x86_rep_stosb_threshold then REP STOSB will be used. + 6. If size is more to 4 * VEC_SIZE, align to 4 * VEC_SIZE with 4 VEC stores and store 4 * VEC at a time until done. */ #include