public inbox for glibc-cvs@sourceware.org
help / color / mirror / Atom feed
* [glibc] x86: Remove generic strncat, strncpy, and stpncpy implementations
@ 2022-07-12 19:24 Noah Goldstein
0 siblings, 0 replies; only message in thread
From: Noah Goldstein @ 2022-07-12 19:24 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=9c38deec96ebe1b052a0c1bef137b90967755f18
commit 9c38deec96ebe1b052a0c1bef137b90967755f18
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Tue Jul 5 17:06:41 2022 -0700
x86: Remove generic strncat, strncpy, and stpncpy implementations
These functions all have optimized versions:
__strncat_sse2_unaligned, __strncpy_sse2_unaligned, and
stpncpy_sse2_unaligned which are faster than their respective generic
implementations. Since the sse2 versions can run on baseline x86_64,
we should use these as the baseline implementation and can remove the
generic implementations.
Geometric mean of N=20 runs of the entire benchmark suite on:
11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz (Tigerlake)
__strncat_sse2_unaligned / __strncat_generic: .944
__strncpy_sse2_unaligned / __strncpy_generic: .726
__stpncpy_sse2_unaligned / __stpncpy_generic: .650
Tested build with and without multiarch and full check with multiarch.
Diff:
---
sysdeps/x86_64/multiarch/Makefile | 3 --
sysdeps/x86_64/multiarch/ifunc-impl-list.c | 9 ++----
sysdeps/x86_64/multiarch/ifunc-strcpy.h | 8 ++---
sysdeps/x86_64/multiarch/ifunc-strncpy.h | 48 ++++++++++++++++++++++++++++++
sysdeps/x86_64/multiarch/stpncpy-generic.c | 26 ----------------
sysdeps/x86_64/multiarch/stpncpy.c | 3 +-
sysdeps/x86_64/multiarch/strncat-generic.c | 21 -------------
sysdeps/x86_64/multiarch/strncat.c | 3 +-
sysdeps/x86_64/multiarch/strncpy-generic.c | 24 ---------------
sysdeps/x86_64/multiarch/strncpy.c | 3 +-
10 files changed, 56 insertions(+), 92 deletions(-)
diff --git a/sysdeps/x86_64/multiarch/Makefile b/sysdeps/x86_64/multiarch/Makefile
index 7ba9ad5139..d6b62af850 100644
--- a/sysdeps/x86_64/multiarch/Makefile
+++ b/sysdeps/x86_64/multiarch/Makefile
@@ -45,7 +45,6 @@ sysdep_routines += \
stpcpy-sse2-unaligned \
stpncpy-avx2 \
stpncpy-avx2-rtm \
- stpncpy-generic \
stpncpy-evex \
stpncpy-sse2-unaligned \
strcasecmp_l-avx2 \
@@ -91,7 +90,6 @@ sysdep_routines += \
strncase_l-sse4_2 \
strncat-avx2 \
strncat-avx2-rtm \
- strncat-generic \
strncat-evex \
strncat-sse2-unaligned \
strncmp-avx2 \
@@ -101,7 +99,6 @@ sysdep_routines += \
strncmp-sse4_2 \
strncpy-avx2 \
strncpy-avx2-rtm \
- strncpy-generic \
strncpy-evex \
strncpy-sse2-unaligned \
strnlen-avx2 \
diff --git a/sysdeps/x86_64/multiarch/ifunc-impl-list.c b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
index adf7d4bafd..2c96cb62d2 100644
--- a/sysdeps/x86_64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/x86_64/multiarch/ifunc-impl-list.c
@@ -403,8 +403,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
&& CPU_FEATURE_USABLE (AVX512BW)),
__stpncpy_evex)
IFUNC_IMPL_ADD (array, i, stpncpy, 1,
- __stpncpy_sse2_unaligned)
- IFUNC_IMPL_ADD (array, i, stpncpy, 1, __stpncpy_generic))
+ __stpncpy_sse2_unaligned))
/* Support sysdeps/x86_64/multiarch/stpcpy.c. */
IFUNC_IMPL (i, name, stpcpy,
@@ -618,8 +617,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
&& CPU_FEATURE_USABLE (AVX512BW)),
__strncat_evex)
IFUNC_IMPL_ADD (array, i, strncat, 1,
- __strncat_sse2_unaligned)
- IFUNC_IMPL_ADD (array, i, strncat, 1, __strncat_generic))
+ __strncat_sse2_unaligned))
/* Support sysdeps/x86_64/multiarch/strncpy.c. */
IFUNC_IMPL (i, name, strncpy,
@@ -634,8 +632,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
&& CPU_FEATURE_USABLE (AVX512BW)),
__strncpy_evex)
IFUNC_IMPL_ADD (array, i, strncpy, 1,
- __strncpy_sse2_unaligned)
- IFUNC_IMPL_ADD (array, i, strncpy, 1, __strncpy_generic))
+ __strncpy_sse2_unaligned))
/* Support sysdeps/x86_64/multiarch/strpbrk.c. */
IFUNC_IMPL (i, name, strpbrk,
diff --git a/sysdeps/x86_64/multiarch/ifunc-strcpy.h b/sysdeps/x86_64/multiarch/ifunc-strcpy.h
index 80529458d1..a15afa44e9 100644
--- a/sysdeps/x86_64/multiarch/ifunc-strcpy.h
+++ b/sysdeps/x86_64/multiarch/ifunc-strcpy.h
@@ -20,11 +20,7 @@
#include <init-arch.h>
-#ifndef GENERIC
-# define GENERIC sse2
-#endif
-
-extern __typeof (REDIRECT_NAME) OPTIMIZE (GENERIC) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
attribute_hidden;
extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
@@ -53,5 +49,5 @@ IFUNC_SELECTOR (void)
if (CPU_FEATURES_ARCH_P (cpu_features, Fast_Unaligned_Load))
return OPTIMIZE (sse2_unaligned);
- return OPTIMIZE (GENERIC);
+ return OPTIMIZE (sse2);
}
diff --git a/sysdeps/x86_64/multiarch/ifunc-strncpy.h b/sysdeps/x86_64/multiarch/ifunc-strncpy.h
new file mode 100644
index 0000000000..323225af4d
--- /dev/null
+++ b/sysdeps/x86_64/multiarch/ifunc-strncpy.h
@@ -0,0 +1,48 @@
+/* Common definition for ifunc st{r|p}n{cpy|cat}
+ All versions must be listed in ifunc-impl-list.c.
+ Copyright (C) 2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <init-arch.h>
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_unaligned)
+ attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2_rtm) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (evex) attribute_hidden;
+
+static inline void *
+IFUNC_SELECTOR (void)
+{
+ const struct cpu_features* cpu_features = __get_cpu_features ();
+
+ if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+ && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+ {
+ if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+ && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+ return OPTIMIZE (evex);
+
+ if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
+ return OPTIMIZE (avx2_rtm);
+
+ if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
+ return OPTIMIZE (avx2);
+ }
+
+ return OPTIMIZE (sse2_unaligned);
+}
diff --git a/sysdeps/x86_64/multiarch/stpncpy-generic.c b/sysdeps/x86_64/multiarch/stpncpy-generic.c
deleted file mode 100644
index 87826845b0..0000000000
--- a/sysdeps/x86_64/multiarch/stpncpy-generic.c
+++ /dev/null
@@ -1,26 +0,0 @@
-/* stpncpy.
- Copyright (C) 2022 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- 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
- <https://www.gnu.org/licenses/>. */
-
-
-#define STPNCPY __stpncpy_generic
-#undef weak_alias
-#define weak_alias(ignored1, ignored2)
-#undef libc_hidden_def
-#define libc_hidden_def(stpncpy)
-
-#include <string/stpncpy.c>
diff --git a/sysdeps/x86_64/multiarch/stpncpy.c b/sysdeps/x86_64/multiarch/stpncpy.c
index 879bc83f0b..a8d083ff0d 100644
--- a/sysdeps/x86_64/multiarch/stpncpy.c
+++ b/sysdeps/x86_64/multiarch/stpncpy.c
@@ -25,9 +25,8 @@
# undef stpncpy
# undef __stpncpy
-# define GENERIC generic
# define SYMBOL_NAME stpncpy
-# include "ifunc-strcpy.h"
+# include "ifunc-strncpy.h"
libc_ifunc_redirected (__redirect_stpncpy, __stpncpy, IFUNC_SELECTOR ());
diff --git a/sysdeps/x86_64/multiarch/strncat-generic.c b/sysdeps/x86_64/multiarch/strncat-generic.c
deleted file mode 100644
index 0090669cd1..0000000000
--- a/sysdeps/x86_64/multiarch/strncat-generic.c
+++ /dev/null
@@ -1,21 +0,0 @@
-/* strncat.
- Copyright (C) 2022 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- 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
- <https://www.gnu.org/licenses/>. */
-
-
-#define STRNCAT __strncat_generic
-#include <string/strncat.c>
diff --git a/sysdeps/x86_64/multiarch/strncat.c b/sysdeps/x86_64/multiarch/strncat.c
index 50fba8a41f..a590c25d51 100644
--- a/sysdeps/x86_64/multiarch/strncat.c
+++ b/sysdeps/x86_64/multiarch/strncat.c
@@ -24,8 +24,7 @@
# undef strncat
# define SYMBOL_NAME strncat
-# define GENERIC generic
-# include "ifunc-strcpy.h"
+# include "ifunc-strncpy.h"
libc_ifunc_redirected (__redirect_strncat, strncat, IFUNC_SELECTOR ());
strong_alias (strncat, __strncat);
diff --git a/sysdeps/x86_64/multiarch/strncpy-generic.c b/sysdeps/x86_64/multiarch/strncpy-generic.c
deleted file mode 100644
index 9916153dd5..0000000000
--- a/sysdeps/x86_64/multiarch/strncpy-generic.c
+++ /dev/null
@@ -1,24 +0,0 @@
-/* strncpy.
- Copyright (C) 2022 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- 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
- <https://www.gnu.org/licenses/>. */
-
-
-#define STRNCPY __strncpy_generic
-#undef libc_hidden_builtin_def
-#define libc_hidden_builtin_def(strncpy)
-
-#include <string/strncpy.c>
diff --git a/sysdeps/x86_64/multiarch/strncpy.c b/sysdeps/x86_64/multiarch/strncpy.c
index 7fc7d72ec5..c83440f0e3 100644
--- a/sysdeps/x86_64/multiarch/strncpy.c
+++ b/sysdeps/x86_64/multiarch/strncpy.c
@@ -24,8 +24,7 @@
# undef strncpy
# define SYMBOL_NAME strncpy
-# define GENERIC generic
-# include "ifunc-strcpy.h"
+# include "ifunc-strncpy.h"
libc_ifunc_redirected (__redirect_strncpy, strncpy, IFUNC_SELECTOR ());
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2022-07-12 19:24 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-12 19:24 [glibc] x86: Remove generic strncat, strncpy, and stpncpy implementations Noah Goldstein
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).