From bb034f8ae84535c1263032311594f229fd3ad1a9 Mon Sep 17 00:00:00 2001
From: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Wed, 23 Mar 2022 16:57:26 -0500
Subject: [PATCH] x86: Remove strcspn-sse2.S and use the generic implementation
The generic implementation is faster.
geometric_mean(N=20) of all benchmarks New / Original: .678
All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit fe28e7d9d9535ebab4081d195c553b4fbf39d9ae)
---
.../{strcspn-sse2.S => strcspn-sse2.c} | 6 +-
sysdeps/x86_64/strcspn.S | 122 ------------------
2 files changed, 3 insertions(+), 125 deletions(-)
rename sysdeps/x86_64/multiarch/{strcspn-sse2.S => strcspn-sse2.c} (89%)
delete mode 100644 sysdeps/x86_64/strcspn.S
diff --git a/sysdeps/x86_64/multiarch/strcspn-sse2.S b/sysdeps/x86_64/multiarch/strcspn-sse2.c
similarity index 89%
rename from sysdeps/x86_64/multiarch/strcspn-sse2.S
rename to sysdeps/x86_64/multiarch/strcspn-sse2.c
index 8a0c69d7..32debee4 100644
--- a/sysdeps/x86_64/multiarch/strcspn-sse2.S
+++ b/sysdeps/x86_64/multiarch/strcspn-sse2.c
@@ -19,10 +19,10 @@
#if IS_IN (libc)
# include <sysdep.h>
-# define strcspn __strcspn_sse2
+# define STRCSPN __strcspn_sse2
# undef libc_hidden_builtin_def
-# define libc_hidden_builtin_def(strcspn)
+# define libc_hidden_builtin_def(STRCSPN)
#endif
-#include <sysdeps/x86_64/strcspn.S>
+#include <string/strcspn.c>
diff --git a/sysdeps/x86_64/strcspn.S b/sysdeps/x86_64/strcspn.S
deleted file mode 100644
index 7f9202d6..00000000
--- a/sysdeps/x86_64/strcspn.S
+++ /dev/null
@@ -1,122 +0,0 @@
-/* strcspn (str, ss) -- Return the length of the initial segment of STR
- which contains no 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>
-#include "asm-syntax.h"
-
- .text
-ENTRY (strcspn)
-
- 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 skipset. */
-
-/* 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 skipset */
- testb %cl, %cl /* is NUL char? */
- jz L(1) /* yes => start compare loop */
- movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */
-
- movb 1(%rax), %cl /* get byte from skipset */
- testb $0xff, %cl /* is NUL char? */
- jz L(1) /* yes => start compare loop */
- movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */
-
- movb 2(%rax), %cl /* get byte from skipset */
- testb $0xff, %cl /* is NUL char? */
- jz L(1) /* yes => start compare loop */
- movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */
-
- movb 3(%rax), %cl /* get byte from skipset */
- addq $4, %rax /* increment skipset pointer */
- movb %cl, (%rsp,%rcx) /* set corresponding byte in skipset table */
- testb $0xff, %cl /* is NUL char? */
- jnz L(2) /* no => process next dword from skipset */
-
-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 skipset was found
- and
- 2. the end of the string was found
- But as a sign that the character is in the skipset 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 */
- cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
- je L(4) /* yes => return */
-
- movb 1(%rax), %cl /* get byte from string */
- cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
- je L(5) /* yes => return */
-
- movb 2(%rax), %cl /* get byte from string */
- cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
- jz L(6) /* yes => return */
-
- movb 3(%rax), %cl /* get byte from string */
- cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
- jne L(3) /* no => start loop again */
-
- incq %rax /* adjust pointer */
-L(6): incq %rax
-L(5): incq %rax
-
-L(4): addq $256, %rsp /* remove skipset */
- cfi_adjust_cfa_offset(-256)
-#ifdef USE_AS_STRPBRK
- xorl %edx,%edx
- orb %cl, %cl /* was last character NUL? */
- cmovzq %rdx, %rax /* Yes: return NULL */
-#else
- subq %rdx, %rax /* we have to return the number of valid
- characters, so compute distance to first
- non-valid character */
-#endif
- ret
-END (strcspn)
-libc_hidden_builtin_def (strcspn)
--
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