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authorRajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com>2016-12-27 17:48:37 -0200
committerTulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>2016-12-28 11:44:31 -0200
commit9314d3545e6641063b490918e2e8716556ba20db (patch)
treecc3d6518db2c0a86db8dcbb22ee44e789a0a9920
parentffcf0f1cb77dd0d902495fd066a96784f76f2c3a (diff)
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powerpc64: strchr/strchrnul optimization for power8
The P7 code is used for <=32B strings and for > 32B vectorized loops are used. This shows as an average 25% improvement depending on the position of search character. The performance is same for shorter strings. Tested on ppc64 and ppc64le.
-rw-r--r--ChangeLog16
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/Makefile4
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c6
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/strchr-power8.S39
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/strchr.c3
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/strchrnul-power8.S39
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/strchrnul.c3
-rw-r--r--sysdeps/powerpc/powerpc64/power8/strchr.S368
-rw-r--r--sysdeps/powerpc/powerpc64/power8/strchrnul.S23
9 files changed, 499 insertions, 2 deletions
diff --git a/ChangeLog b/ChangeLog
index b794cac..d9b2c98 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+2016-12-28 Rajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com>
+
+ * sysdeps/powerpc/powerpc64/multiarch/Makefile
+ (sysdep_routines): Add strchr-power8 and strchrnul_power8.
+ * sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
+ (strchr): Add __strchr_power8 to list of strchr functions.
+ (strchrnul): Add __strchrnul_power8 to list of strchr functions.
+ * sysdeps/powerpc/powerpc64/multiarch/strchr-power8.S: New file.
+ * sysdeps/powerpc/powerpc64/multiarch/strchrnul-power8.S: New file.
+ * sysdeps/powerpc/powerpc64/multiarch/strchr.c
+ (strchr): Add __strchr_power8 to ifunc list.
+ * sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
+ (__strchrnul): Add __strchrnul_power8 to ifunc list.
+ * sysdeps/powerpc/powerpc64/power8/strchr.S: New file.
+ * sysdeps/powerpc/powerpc64/power8/strchrnul.S: New file.
+
2016-12-28 Florian Weimer <fweimer@redhat.com>
* support/Makefile (libsupport-routines): Add
diff --git a/sysdeps/powerpc/powerpc64/multiarch/Makefile b/sysdeps/powerpc/powerpc64/multiarch/Makefile
index 2997b9d..f5889a3 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc64/multiarch/Makefile
@@ -10,8 +10,8 @@ sysdep_routines += memcpy-power7 memcpy-a2 memcpy-power6 memcpy-cell \
strncase-power7 strncase_l-power7 \
strncmp-power9 strncmp-power8 strncmp-power7 \
strncmp-power4 strncmp-ppc64 \
- strchr-power7 strchr-ppc64 \
- strchrnul-power7 strchrnul-ppc64 \
+ strchr-power8 strchr-power7 strchr-ppc64 \
+ strchrnul-power8 strchrnul-power7 strchrnul-ppc64 \
strcpy-power8 strcpy-power7 strcpy-ppc64 stpcpy-power8 \
stpcpy-power7 stpcpy-ppc64 \
strrchr-power7 strrchr-ppc64 strncat-power7 strncat-ppc64 \
diff --git a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
index 2d085a2..703a49b 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
@@ -124,6 +124,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/powerpc/powerpc64/multiarch/strchr.c. */
IFUNC_IMPL (i, name, strchr,
IFUNC_IMPL_ADD (array, i, strchr,
+ hwcap2 & PPC_FEATURE2_ARCH_2_07,
+ __strchr_power8)
+ IFUNC_IMPL_ADD (array, i, strchr,
hwcap & PPC_FEATURE_HAS_VSX,
__strchr_power7)
IFUNC_IMPL_ADD (array, i, strchr, 1,
@@ -132,6 +135,9 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/powerpc/powerpc64/multiarch/strchrnul.c. */
IFUNC_IMPL (i, name, strchrnul,
IFUNC_IMPL_ADD (array, i, strchrnul,
+ hwcap2 & PPC_FEATURE2_ARCH_2_07,
+ __strchrnul_power8)
+ IFUNC_IMPL_ADD (array, i, strchrnul,
hwcap & PPC_FEATURE_HAS_VSX,
__strchrnul_power7)
IFUNC_IMPL_ADD (array, i, strchrnul, 1,
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strchr-power8.S b/sysdeps/powerpc/powerpc64/multiarch/strchr-power8.S
new file mode 100644
index 0000000..dd0b7f5
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strchr-power8.S
@@ -0,0 +1,39 @@
+/* Optimized strchr implementation for POWER8.
+ Copyright (C) 2016 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/>. */
+
+#include <sysdep.h>
+
+#undef ENTRY
+#define ENTRY(name) \
+ .section ".text"; \
+ ENTRY_2(__strchr_power8) \
+ .align ALIGNARG(2); \
+ BODY_LABEL(__strchr_power8): \
+ cfi_startproc; \
+ LOCALENTRY(__strchr_power8)
+
+#undef END
+#define END(name) \
+ cfi_endproc; \
+ TRACEBACK(__strchr_power8) \
+ END_2(__strchr_power8)
+
+#undef libc_hidden_builtin_def
+#define libc_hidden_builtin_def(name)
+
+#include <sysdeps/powerpc/powerpc64/power8/strchr.S>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strchr.c b/sysdeps/powerpc/powerpc64/multiarch/strchr.c
index e24d6b3..2ffb1f6 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strchr.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strchr.c
@@ -27,11 +27,14 @@
extern __typeof (strchr) __strchr_ppc attribute_hidden;
extern __typeof (strchr) __strchr_power7 attribute_hidden;
+extern __typeof (strchr) __strchr_power8 attribute_hidden;
# undef strchr
/* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
ifunc symbol properly. */
libc_ifunc_redirected (__redirect_strchr, strchr,
+ (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+ ? __strchr_power8 :
(hwcap & PPC_FEATURE_HAS_VSX)
? __strchr_power7
: __strchr_ppc);
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strchrnul-power8.S b/sysdeps/powerpc/powerpc64/multiarch/strchrnul-power8.S
new file mode 100644
index 0000000..d0bfeda
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strchrnul-power8.S
@@ -0,0 +1,39 @@
+/* Optimized strchrnul implementation for POWER8.
+ Copyright (C) 2016 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/>. */
+
+#include <sysdep.h>
+
+#undef ENTRY
+#define ENTRY(name) \
+ .section ".text"; \
+ ENTRY_2(__strchrnul_power8) \
+ .align ALIGNARG(2); \
+ BODY_LABEL(__strchrnul_power8): \
+ cfi_startproc; \
+ LOCALENTRY(__strchrnul_power8)
+
+#undef END
+#define END(name) \
+ cfi_endproc; \
+ TRACEBACK(__strchrnul_power8) \
+ END_2(__strchrnul_power8)
+
+#undef libc_hidden_builtin_def
+#define libc_hidden_builtin_def(name)
+
+#include <sysdeps/powerpc/powerpc64/power8/strchrnul.S>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c b/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
index 682aa0f..63df401 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
@@ -23,10 +23,13 @@
extern __typeof (__strchrnul) __strchrnul_ppc attribute_hidden;
extern __typeof (__strchrnul) __strchrnul_power7 attribute_hidden;
+extern __typeof (__strchrnul) __strchrnul_power8 attribute_hidden;
/* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
ifunc symbol properly. */
libc_ifunc (__strchrnul,
+ (hwcap2 & PPC_FEATURE2_ARCH_2_07)
+ ? __strchrnul_power8 :
(hwcap & PPC_FEATURE_HAS_VSX)
? __strchrnul_power7
: __strchrnul_ppc);
diff --git a/sysdeps/powerpc/powerpc64/power8/strchr.S b/sysdeps/powerpc/powerpc64/power8/strchr.S
new file mode 100644
index 0000000..331d0a6
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/power8/strchr.S
@@ -0,0 +1,368 @@
+/* Optimized strchr implementation for PowerPC64/POWER8.
+ Copyright (C) 2016 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/>. */
+
+#include <sysdep.h>
+
+#ifdef USE_AS_STRCHRNUL
+# define FUNC_NAME __strchrnul
+#else
+# define FUNC_NAME strchr
+#endif
+/* int [r3] strchr (char *s [r3], int c [r4]) */
+/* TODO: change these to the actual instructions when the minimum required
+ binutils allows it. */
+#define MTVRD(v,r) .long (0x7c000167 | ((v)<<(32-11)) | ((r)<<(32-16)))
+#define MFVRD(r,v) .long (0x7c000067 | ((v)<<(32-11)) | ((r)<<(32-16)))
+#define VBPERMQ(t,a,b) .long (0x1000054c \
+ | ((t)<<(32-11)) \
+ | ((a)<<(32-16)) \
+ | ((b)<<(32-21)) )
+/* TODO: change this to .machine power8 when the minimum required binutils
+ allows it. */
+ .machine power7
+ENTRY (FUNC_NAME)
+ CALL_MCOUNT 2
+ dcbt 0,r3
+ clrrdi r8,r3,3 /* Align the address to doubleword boundary. */
+ cmpdi cr7,r4,0
+ ld r12,0(r8) /* Load doubleword from memory. */
+ li r0,0 /* Doubleword with null chars to use
+ with cmpb. */
+
+ rlwinm r6,r3,3,26,28 /* Calculate padding. */
+
+ beq cr7,L(null_match)
+
+ /* Replicate byte to doubleword. */
+ insrdi r4,r4,8,48
+ insrdi r4,r4,16,32
+ insrdi r4,r4,32,0
+
+ /* Now r4 has a doubleword of c bytes and r0 has
+ a doubleword of null bytes. */
+
+ cmpb r10,r12,r4 /* Compare each byte against c byte. */
+ cmpb r11,r12,r0 /* Compare each byte against null byte. */
+
+ /* Move the doublewords left and right to discard the bits that are
+ not part of the string and bring them back as zeros. */
+#ifdef __LITTLE_ENDIAN__
+ srd r10,r10,r6
+ srd r11,r11,r6
+ sld r10,r10,r6
+ sld r11,r11,r6
+#else
+ sld r10,r10,r6
+ sld r11,r11,r6
+ srd r10,r10,r6
+ srd r11,r11,r6
+#endif
+ or r5,r10,r11 /* OR the results to speed things up. */
+ cmpdi cr7,r5,0 /* If r5 == 0, no c or null bytes
+ have been found. */
+ bne cr7,L(done)
+
+ mtcrf 0x01,r8
+
+ /* Are we now aligned to a doubleword boundary? If so, skip to
+ the main loop. Otherwise, go through the alignment code. */
+
+ bt 28,L(loop)
+
+ /* Handle WORD2 of pair. */
+ ldu r12,8(r8)
+ cmpb r10,r12,r4
+ cmpb r11,r12,r0
+ or r5,r10,r11
+ cmpdi cr7,r5,0
+ bne cr7,L(done)
+ b L(loop) /* We branch here (rather than falling through)
+ to skip the nops due to heavy alignment
+ of the loop below. */
+
+ .p2align 5
+L(loop):
+ /* Load two doublewords, compare and merge in a
+ single register for speed. This is an attempt
+ to speed up the null-checking process for bigger strings. */
+ ld r12,8(r8)
+ ldu r9,16(r8)
+ cmpb r10,r12,r4
+ cmpb r11,r12,r0
+ cmpb r6,r9,r4
+ cmpb r7,r9,r0
+ or r5,r10,r11
+ or r9,r6,r7
+ or r12,r5,r9
+ cmpdi cr7,r12,0
+ beq cr7,L(vector)
+ /* OK, one (or both) of the doublewords contains a c/null byte. Check
+ the first doubleword and decrement the address in case the first
+ doubleword really contains a c/null byte. */
+
+ cmpdi cr6,r5,0
+ addi r8,r8,-8
+ bne cr6,L(done)
+
+ /* The c/null byte must be in the second doubleword. Adjust the
+ address again and move the result of cmpb to r10 so we can calculate
+ the pointer. */
+
+ mr r10,r6
+ mr r11,r7
+ addi r8,r8,8
+#ifdef USE_AS_STRCHRNUL
+ mr r5, r9
+#endif
+ /* r10/r11 have the output of the cmpb instructions, that is,
+ 0xff in the same position as the c/null byte in the original
+ doubleword from the string. Use that to calculate the pointer. */
+L(done):
+#ifdef USE_AS_STRCHRNUL
+ mr r10, r5
+#endif
+#ifdef __LITTLE_ENDIAN__
+ addi r3,r10,-1
+ andc r3,r3,r10
+ popcntd r0,r3
+# ifndef USE_AS_STRCHRNUL
+ addi r4,r11,-1
+ andc r4,r4,r11
+ cmpld cr7,r3,r4
+ bgt cr7,L(no_match)
+# endif
+#else
+ cntlzd r0,r10 /* Count leading zeros before c matches. */
+# ifndef USE_AS_STRCHRNUL
+ cmpld cr7,r11,r10
+ bgt cr7,L(no_match)
+# endif
+#endif
+ srdi r0,r0,3 /* Convert leading zeros to bytes. */
+ add r3,r8,r0 /* Return address of the matching c byte
+ or null in case c was not found. */
+ blr
+
+ /* Check the first 32B in GPR's and move to vectorized loop. */
+ .p2align 5
+L(vector):
+ addi r3, r8, 8
+ andi. r10, r3, 31
+ bne cr0, L(loop)
+ vspltisb v0, 0
+ /* Precompute vbpermq constant. */
+ vspltisb v10, 3
+ lvsl v11, r0, r0
+ vslb v10, v11, v10
+ MTVRD(v1,r4)
+ li r5, 16
+ vspltb v1, v1, 7
+ /* Compare 32 bytes in each loop. */
+L(continue):
+ lvx v4, 0, r3
+ lvx v5, r3, r5
+ vcmpequb v2, v0, v4
+ vcmpequb v3, v0, v5
+ vcmpequb v6, v1, v4
+ vcmpequb v7, v1, v5
+ vor v8, v2, v3
+ vor v9, v6, v7
+ vor v11, v8, v9
+ vcmpequb. v11, v0, v11
+ addi r3, r3, 32
+ blt cr6, L(continue)
+ /* One (or both) of the quadwords contains a c/null byte. */
+ addi r3, r3, -32
+#ifndef USE_AS_STRCHRNUL
+ vcmpequb. v11, v0, v9
+ blt cr6, L(no_match)
+#endif
+ /* Permute the first bit of each byte into bits 48-63. */
+ VBPERMQ(v2, v2, v10)
+ VBPERMQ(v3, v3, v10)
+ VBPERMQ(v6, v6, v10)
+ VBPERMQ(v7, v7, v10)
+ /* Shift each component into its correct position for merging. */
+#ifdef __LITTLE_ENDIAN__
+ vsldoi v3, v3, v3, 2
+ vsldoi v7, v7, v7, 2
+#else
+ vsldoi v2, v2, v2, 6
+ vsldoi v3, v3, v3, 4
+ vsldoi v6, v6, v6, 6
+ vsldoi v7, v7, v7, 4
+#endif
+
+ /* Merge the results and move to a GPR. */
+ vor v1, v3, v2
+ vor v2, v6, v7
+ vor v4, v1, v2
+ MFVRD(r5, v4)
+#ifdef __LITTLE_ENDIAN__
+ addi r6, r5, -1
+ andc r6, r6, r5
+ popcntd r6, r6
+#else
+ cntlzd r6, r5 /* Count leading zeros before the match. */
+#endif
+ add r3, r3, r6 /* Compute final length. */
+ /* Return NULL if null found before c. */
+#ifndef USE_AS_STRCHRNUL
+ lbz r4, 0(r3)
+ cmpdi cr7, r4, 0
+ beq cr7, L(no_match)
+#endif
+ blr
+
+#ifndef USE_AS_STRCHRNUL
+ .align 4
+L(no_match):
+ li r3,0
+ blr
+#endif
+
+/* We are here because strchr was called with a null byte. */
+ .align 4
+L(null_match):
+ /* r0 has a doubleword of null bytes. */
+
+ cmpb r5,r12,r0 /* Compare each byte against null bytes. */
+
+ /* Move the doublewords left and right to discard the bits that are
+ not part of the string and bring them back as zeros. */
+#ifdef __LITTLE_ENDIAN__
+ srd r5,r5,r6
+ sld r5,r5,r6
+#else
+ sld r5,r5,r6
+ srd r5,r5,r6
+#endif
+ cmpdi cr7,r5,0 /* If r10 == 0, no c or null bytes
+ have been found. */
+ bne cr7,L(done_null)
+
+ mtcrf 0x01,r8
+
+ /* Are we now aligned to a quadword boundary? If so, skip to
+ the main loop. Otherwise, go through the alignment code. */
+
+ bt 28,L(loop_null)
+
+ /* Handle WORD2 of pair. */
+ ldu r12,8(r8)
+ cmpb r5,r12,r0
+ cmpdi cr7,r5,0
+ bne cr7,L(done_null)
+ b L(loop_null) /* We branch here (rather than falling through)
+ to skip the nops due to heavy alignment
+ of the loop below. */
+
+ /* Main loop to look for the end of the string. Since it's a
+ small loop (< 8 instructions), align it to 32-bytes. */
+ .p2align 5
+L(loop_null):
+ /* Load two doublewords, compare and merge in a
+ single register for speed. This is an attempt
+ to speed up the null-checking process for bigger strings. */
+ ld r12,8(r8)
+ ldu r11,16(r8)
+ cmpb r5,r12,r0
+ cmpb r10,r11,r0
+ or r6,r5,r10
+ cmpdi cr7,r6,0
+ beq cr7,L(vector1)
+
+ /* OK, one (or both) of the doublewords contains a null byte. Check
+ the first doubleword and decrement the address in case the first
+ doubleword really contains a null byte. */
+
+ cmpdi cr6,r5,0
+ addi r8,r8,-8
+ bne cr6,L(done_null)
+
+ /* The null byte must be in the second doubleword. Adjust the address
+ again and move the result of cmpb to r10 so we can calculate the
+ pointer. */
+
+ mr r5,r10
+ addi r8,r8,8
+
+ /* r5 has the output of the cmpb instruction, that is, it contains
+ 0xff in the same position as the null byte in the original
+ doubleword from the string. Use that to calculate the pointer. */
+L(done_null):
+#ifdef __LITTLE_ENDIAN__
+ addi r0,r5,-1
+ andc r0,r0,r5
+ popcntd r0,r0
+#else
+ cntlzd r0,r5 /* Count leading zeros before the match. */
+#endif
+ srdi r0,r0,3 /* Convert leading zeros to bytes. */
+ add r3,r8,r0 /* Return address of the matching null byte. */
+ blr
+ .p2align 5
+L(vector1):
+ addi r3, r8, 8
+ andi. r10, r3, 31
+ bne cr0, L(loop_null)
+ vspltisb v8, -1
+ vspltisb v0, 0
+ vspltisb v10, 3
+ lvsl v11, r0, r0
+ vslb v10, v11, v10
+ li r5, 16
+L(continue1):
+ lvx v4, 0, r3
+ lvx v5, r3, r5
+ vcmpequb v2, v0, v4
+ vcmpequb v3, v0, v5
+ vor v8, v2, v3
+ vcmpequb. v11, v0, v8
+ addi r3, r3, 32
+ blt cr6, L(continue1)
+ addi r3, r3, -32
+L(end1):
+ VBPERMQ(v2, v2, v10)
+ VBPERMQ(v3, v3, v10)
+ /* Shift each component into its correct position for merging. */
+#ifdef __LITTLE_ENDIAN__
+ vsldoi v3, v3, v3, 2
+#else
+ vsldoi v2, v2, v2, 6
+ vsldoi v3, v3, v3, 4
+#endif
+
+ /* Merge the results and move to a GPR. */
+ vor v4, v3, v2
+ MFVRD(r5, v4)
+#ifdef __LITTLE_ENDIAN__
+ addi r6, r5, -1
+ andc r6, r6, r5
+ popcntd r6, r6
+#else
+ cntlzd r6, r5 /* Count leading zeros before the match. */
+#endif
+ add r3, r3, r6 /* Compute final length. */
+ blr
+END (FUNC_NAME)
+
+#ifndef USE_AS_STRCHRNUL
+weak_alias (strchr, index)
+libc_hidden_builtin_def (strchr)
+#endif
diff --git a/sysdeps/powerpc/powerpc64/power8/strchrnul.S b/sysdeps/powerpc/powerpc64/power8/strchrnul.S
new file mode 100644
index 0000000..0229496
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/power8/strchrnul.S
@@ -0,0 +1,23 @@
+/* Optimized strchrnul implementation for PowerPC64/POWER8.
+ Copyright (C) 2016 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 USE_AS_STRCHRNUL 1
+#include <sysdeps/powerpc/powerpc64/power8/strchr.S>
+
+weak_alias (__strchrnul,strchrnul)
+libc_hidden_builtin_def (__strchrnul)