glibc/glibc-RHEL-15696-94.patch

From 9c8a6ad620b49a27120ecdd7049c26bf05900397 Mon Sep 17 00:00:00 2001
From: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Wed, 23 Mar 2022 16:57:29 -0500
Subject: [PATCH] x86: Remove strspn-sse2.S and use the generic implementation
Content-type: text/plain; charset=UTF-8

The generic implementation is faster.

geometric_mean(N=20) of all benchmarks New / Original: .710

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
---
 .../{strspn-sse2.S => strspn-sse2.c}          |   6 +-
 sysdeps/x86_64/strspn.S                       | 115 ------------------
 2 files changed, 3 insertions(+), 118 deletions(-)
 rename sysdeps/x86_64/multiarch/{strspn-sse2.S => strspn-sse2.c} (89%)
 delete mode 100644 sysdeps/x86_64/strspn.S

Conflicts:
	sysdeps/x86_64/multiarch/strspn-sse2.c
	(copyright header)

diff --git a/sysdeps/x86_64/multiarch/strspn-sse2.S b/sysdeps/x86_64/multiarch/strspn-sse2.c
similarity index 89%
rename from sysdeps/x86_64/multiarch/strspn-sse2.S
rename to sysdeps/x86_64/multiarch/strspn-sse2.c
index 4686cdd5..ab0dae40 100644
--- a/sysdeps/x86_64/multiarch/strspn-sse2.S
+++ b/sysdeps/x86_64/multiarch/strspn-sse2.c
@@ -19,10 +19,10 @@
 #if IS_IN (libc)
 
 # include <sysdep.h>
-# define strspn __strspn_sse2
+# define STRSPN __strspn_sse2
 
 # undef libc_hidden_builtin_def
-# define libc_hidden_builtin_def(strspn)
+# define libc_hidden_builtin_def(STRSPN)
 #endif
 
-#include <sysdeps/x86_64/strspn.S>
+#include <string/strspn.c>
diff --git a/sysdeps/x86_64/strspn.S b/sysdeps/x86_64/strspn.S
deleted file mode 100644
index 635f1bc6..00000000
--- a/sysdeps/x86_64/strspn.S
+++ /dev/null
@@ -1,115 +0,0 @@
-/* strspn (str, ss) -- Return the length of the initial segment of STR
-			which contains only characters from SS.
-   For AMD x86-64.
-   Copyright (C) 1994-2018 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>.
-   Bug fixes by Alan Modra <Alan@SPRI.Levels.UniSA.Edu.Au>.
-   Adopted for x86-64 by Andreas Jaeger <aj@suse.de>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <sysdep.h>
-
-	.text
-ENTRY (strspn)
-
-	movq %rdi, %rdx		/* Save SRC.  */
-
-	/* First we create a table with flags for all possible characters.
-	   For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
-	   supported by the C string functions we have 256 characters.
-	   Before inserting marks for the stop characters we clear the whole
-	   table.  */
-	movq %rdi, %r8			/* Save value.  */
-	subq $256, %rsp			/* Make space for 256 bytes.  */
-	cfi_adjust_cfa_offset(256)
-	movl $32,  %ecx			/* 32*8 bytes = 256 bytes.  */
-	movq %rsp, %rdi
-	xorl %eax, %eax			/* We store 0s.  */
-	cld
-	rep
-	stosq
-
-	movq %rsi, %rax			/* Setup stopset.  */
-
-/* For understanding the following code remember that %rcx == 0 now.
-   Although all the following instruction only modify %cl we always
-   have a correct zero-extended 64-bit value in %rcx.  */
-
-	.p2align 4
-L(2):	movb (%rax), %cl	/* get byte from stopset */
-	testb %cl, %cl		/* is NUL char? */
-	jz L(1)			/* yes => start compare loop */
-	movb %cl, (%rsp,%rcx)	/* set corresponding byte in stopset table */
-
-	movb 1(%rax), %cl	/* get byte from stopset */
-	testb $0xff, %cl	/* is NUL char? */
-	jz L(1)			/* yes => start compare loop */
-	movb %cl, (%rsp,%rcx)	/* set corresponding byte in stopset table */
-
-	movb 2(%rax), %cl	/* get byte from stopset */
-	testb $0xff, %cl	/* is NUL char? */
-	jz L(1)			/* yes => start compare loop */
-	movb %cl, (%rsp,%rcx)	/* set corresponding byte in stopset table */
-
-	movb 3(%rax), %cl	/* get byte from stopset */
-	addq $4, %rax		/* increment stopset pointer */
-	movb %cl, (%rsp,%rcx)	/* set corresponding byte in stopset table */
-	testb $0xff, %cl	/* is NUL char? */
-	jnz L(2)		/* no => process next dword from stopset */
-
-L(1):	leaq -4(%rdx), %rax	/* prepare loop */
-
-	/* We use a neat trick for the following loop.  Normally we would
-	   have to test for two termination conditions
-	   1. a character in the stopset was found
-	   and
-	   2. the end of the string was found
-	   But as a sign that the character is in the stopset we store its
-	   value in the table.  But the value of NUL is NUL so the loop
-	   terminates for NUL in every case.  */
-
-	.p2align 4
-L(3):	addq $4, %rax		/* adjust pointer for full loop round */
-
-	movb (%rax), %cl	/* get byte from string */
-	testb %cl, (%rsp,%rcx)	/* is it contained in skipset? */
-	jz L(4)			/* no => return */
-
-	movb 1(%rax), %cl	/* get byte from string */
-	testb %cl, (%rsp,%rcx)	/* is it contained in skipset? */
-	jz L(5)			/* no => return */
-
-	movb 2(%rax), %cl	/* get byte from string */
-	testb %cl, (%rsp,%rcx)	/* is it contained in skipset? */
-	jz L(6)			/* no => return */
-
-	movb 3(%rax), %cl	/* get byte from string */
-	testb %cl, (%rsp,%rcx)	/* is it contained in skipset? */
-	jnz L(3)		/* yes => start loop again */
-
-	incq %rax		/* adjust pointer */
-L(6):	incq %rax
-L(5):	incq %rax
-
-L(4):	addq $256, %rsp		/* remove stopset */
-	cfi_adjust_cfa_offset(-256)
-	subq %rdx, %rax		/* we have to return the number of valid
-				   characters, so compute distance to first
-				   non-valid character */
-	ret
-END (strspn)
-libc_hidden_builtin_def (strspn)
-- 
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