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Diffstat (limited to 'sysdeps/x86_64/multiarch/strchr.c')
-rw-r--r--sysdeps/x86_64/multiarch/strchr.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/strchr.c b/sysdeps/x86_64/multiarch/strchr.c
new file mode 100644
index 0000000000..76d64fb378
--- /dev/null
+++ b/sysdeps/x86_64/multiarch/strchr.c
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+/* Multiple versions of strchr.
+ All versions must be listed in ifunc-impl-list.c.
+ Copyright (C) 2009-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+/* Define multiple versions only for the definition in libc. */
+#if IS_IN (libc)
+# define strchr __redirect_strchr
+# include <string.h>
+# undef strchr
+
+# define SYMBOL_NAME strchr
+# include <init-arch.h>
+
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2_no_bsf) attribute_hidden;
+extern __typeof (REDIRECT_NAME) OPTIMIZE (avx2) attribute_hidden;
+
+static inline void *
+IFUNC_SELECTOR (void)
+{
+ const struct cpu_features* cpu_features = __get_cpu_features ();
+
+ if (!CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER)
+ && CPU_FEATURES_ARCH_P (cpu_features, AVX2_Usable)
+ && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+ return OPTIMIZE (avx2);
+
+ if (CPU_FEATURES_ARCH_P (cpu_features, Slow_BSF))
+ return OPTIMIZE (sse2_no_bsf);
+
+ return OPTIMIZE (sse2);
+}
+
+libc_ifunc_redirected (__redirect_strchr, strchr, IFUNC_SELECTOR ());
+weak_alias (strchr, index)
+# ifdef SHARED
+__hidden_ver1 (strchr, __GI_strchr, __redirect_strchr)
+ __attribute__((visibility ("hidden")));
+# endif
+#endif