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glibc/SOURCES/glibc-RHEL-49489-4.patch

596 lines
18 KiB

commit 92fdb11ae7aa1ab6b18622670ea702205cd6fdc5
Author: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>
Date: Tue Feb 28 14:23:59 2023 -0300
powerpc: Remove powerpc64 strncmp variants
The default, and power7 implementation just adds word aligned
access when inputs have the same aligment. The unaligned case
is still done by byte operations.
This is already covered by the generic implementation, which also add
the unaligned input optimization.
Checked on powerpc64-linux-gnu built without multi-arch for powerpc64,
power7, power8, and power9 (build for le).
Reviewed-by: Rajalakshmi Srinivasaraghavan <rajis@linux.ibm.com>
Conflicts:
sysdeps/powerpc/powerpc64/multiarch/strncmp-power7.S
sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.S
sysdeps/powerpc/powerpc64/power7/strncmp.S
sysdeps/powerpc/powerpc64/strncmp.S
(copyright year changes upstream)
diff --git a/sysdeps/powerpc/powerpc64/multiarch/Makefile b/sysdeps/powerpc/powerpc64/multiarch/Makefile
index 5b20dab108de14ab..0ee7ce39d6470d80 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc64/multiarch/Makefile
@@ -12,7 +12,7 @@ sysdep_routines += memcpy-power8-cached memcpy-power7 memcpy-a2 memcpy-power6 \
strnlen-power8 strnlen-power7 strnlen-ppc64 \
strcasecmp-power7 strcasecmp_l-power7 \
strncase-power7 strncase_l-power7 \
- strncmp-power8 strncmp-power7 strncmp-ppc64 \
+ strncmp-power8 strncmp-ppc64 \
strchr-power8 strchr-power7 strchr-ppc64 \
strchrnul-power8 strchrnul-power7 strchrnul-ppc64 \
strcpy-power8 strcpy-power7 strcpy-ppc64 stpcpy-power8 \
diff --git a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
index 914e7d5e28a98b5d..2c84d287ee76a7ea 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
@@ -175,8 +175,6 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
#endif
IFUNC_IMPL_ADD (array, i, strncmp, hwcap2 & PPC_FEATURE2_ARCH_2_07,
__strncmp_power8)
- IFUNC_IMPL_ADD (array, i, strncmp, hwcap & PPC_FEATURE_ARCH_2_06,
- __strncmp_power7)
IFUNC_IMPL_ADD (array, i, strncmp, 1,
__strncmp_ppc))
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strncmp-power7.S b/sysdeps/powerpc/powerpc64/multiarch/strncmp-power7.S
deleted file mode 100644
index 8282ff076c9e00ce..0000000000000000
--- a/sysdeps/powerpc/powerpc64/multiarch/strncmp-power7.S
+++ /dev/null
@@ -1,23 +0,0 @@
-/* Copyright (C) 2013-2021 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 STRNCMP __strncmp_power7
-
-#undef libc_hidden_builtin_def
-#define libc_hidden_builtin_def(name)
-
-#include <sysdeps/powerpc/powerpc64/power7/strncmp.S>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.S b/sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.S
deleted file mode 100644
index c6f325650c9ace3b..0000000000000000
--- a/sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.S
+++ /dev/null
@@ -1,26 +0,0 @@
-/* Copyright (C) 2013-2021 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/>. */
-
-#if defined SHARED && IS_IN (libc)
-# define STRNCMP __strncmp_ppc
-
-# undef libc_hidden_builtin_def
-# define libc_hidden_builtin_def(name) \
- .globl __GI_strncmp; __GI_strncmp = __strncmp_ppc
-#endif
-
-#include <sysdeps/powerpc/powerpc64/strncmp.S>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.c b/sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.c
new file mode 100644
index 0000000000000000..09cc009a913ed169
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strncmp-ppc64.c
@@ -0,0 +1,7 @@
+#if defined SHARED && IS_IN (libc)
+# define STRNCMP __strncmp_ppc
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(name) \
+ __hidden_ver1 (__strncmp_ppc, __GI_strncmp, __strncmp_ppc);
+#endif
+#include <string/strncmp.c>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strncmp.c b/sysdeps/powerpc/powerpc64/multiarch/strncmp.c
index 275a558e4afa7d61..df2c0707a919ad79 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strncmp.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strncmp.c
@@ -26,7 +26,6 @@
# include "init-arch.h"
extern __typeof (strncmp) __strncmp_ppc attribute_hidden;
-extern __typeof (strncmp) __strncmp_power7 attribute_hidden;
extern __typeof (strncmp) __strncmp_power8 attribute_hidden;
# ifdef __LITTLE_ENDIAN__
extern __typeof (strncmp) __strncmp_power9 attribute_hidden;
@@ -43,7 +42,5 @@ libc_ifunc_redirected (__redirect_strncmp, strncmp,
# endif
(hwcap2 & PPC_FEATURE2_ARCH_2_07)
? __strncmp_power8
- : (hwcap & PPC_FEATURE_ARCH_2_06)
- ? __strncmp_power7
- : __strncmp_ppc);
+ : __strncmp_ppc);
#endif
diff --git a/sysdeps/powerpc/powerpc64/power7/strncmp.S b/sysdeps/powerpc/powerpc64/power7/strncmp.S
deleted file mode 100644
index d91aeb6077a558f2..0000000000000000
--- a/sysdeps/powerpc/powerpc64/power7/strncmp.S
+++ /dev/null
@@ -1,228 +0,0 @@
-/* Optimized strcmp implementation for POWER7/PowerPC64.
- Copyright (C) 2010-2021 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 <sysdep.h>
-
-#ifndef STRNCMP
-# define STRNCMP strncmp
-#endif
-
-/* See strlen.s for comments on how the end-of-string testing works. */
-
-/* int [r3] strncmp (const char *s1 [r3],
- const char *s2 [r4],
- size_t size [r5]) */
-
- .machine power7
-ENTRY_TOCLESS (STRNCMP, 5)
- CALL_MCOUNT 3
-
-#define rTMP2 r0
-#define rRTN r3
-#define rSTR1 r3 /* first string arg */
-#define rSTR2 r4 /* second string arg */
-#define rN r5 /* max string length */
-#define rWORD1 r6 /* current word in s1 */
-#define rWORD2 r7 /* current word in s2 */
-#define rWORD3 r10
-#define rWORD4 r11
-#define rFEFE r8 /* constant 0xfefefefefefefeff (-0x0101010101010101) */
-#define r7F7F r9 /* constant 0x7f7f7f7f7f7f7f7f */
-#define rNEG r10 /* ~(word in s1 | 0x7f7f7f7f7f7f7f7f) */
-#define rBITDIF r11 /* bits that differ in s1 & s2 words */
-#define rTMP r12
-
- dcbt 0,rSTR1
- nop
- or rTMP,rSTR2,rSTR1
- lis r7F7F,0x7f7f
- dcbt 0,rSTR2
- nop
- clrldi. rTMP,rTMP,61
- cmpldi cr1,rN,0
- lis rFEFE,-0x101
- bne L(unaligned)
-/* We are doubleword aligned so set up for two loops. first a double word
- loop, then fall into the byte loop if any residual. */
- srdi. rTMP,rN,3
- clrldi rN,rN,61
- addi rFEFE,rFEFE,-0x101
- addi r7F7F,r7F7F,0x7f7f
- cmpldi cr1,rN,0
- beq L(unaligned)
-
- mtctr rTMP
- ld rWORD1,0(rSTR1)
- ld rWORD2,0(rSTR2)
- sldi rTMP,rFEFE,32
- insrdi r7F7F,r7F7F,32,0
- add rFEFE,rFEFE,rTMP
- b L(g1)
-
-L(g0):
- ldu rWORD1,8(rSTR1)
- bne cr1,L(different)
- ldu rWORD2,8(rSTR2)
-L(g1): add rTMP,rFEFE,rWORD1
- nor rNEG,r7F7F,rWORD1
- bdz L(tail)
- and. rTMP,rTMP,rNEG
- cmpd cr1,rWORD1,rWORD2
- beq L(g0)
-
-/* OK. We've hit the end of the string. We need to be careful that
- we don't compare two strings as different because of gunk beyond
- the end of the strings... */
-
-#ifdef __LITTLE_ENDIAN__
-L(endstring):
- addi rTMP2, rTMP, -1
- beq cr1, L(equal)
- andc rTMP2, rTMP2, rTMP
- rldimi rTMP2, rTMP2, 1, 0
- and rWORD2, rWORD2, rTMP2 /* Mask off gunk. */
- and rWORD1, rWORD1, rTMP2
- cmpd cr1, rWORD1, rWORD2
- beq cr1, L(equal)
- cmpb rBITDIF, rWORD1, rWORD2 /* 0xff on equal bytes. */
- addi rNEG, rBITDIF, 1
- orc rNEG, rNEG, rBITDIF /* 0's below LS differing byte. */
- sldi rNEG, rNEG, 8 /* 1's above LS differing byte. */
- andc rWORD1, rWORD1, rNEG /* mask off MS bytes. */
- andc rWORD2, rWORD2, rNEG
- xor. rBITDIF, rWORD1, rWORD2
- sub rRTN, rWORD1, rWORD2
- blt L(highbit)
- sradi rRTN, rRTN, 63 /* must return an int. */
- ori rRTN, rRTN, 1
- blr
-L(equal):
- li rRTN, 0
- blr
-
-L(different):
- ld rWORD1, -8(rSTR1)
- cmpb rBITDIF, rWORD1, rWORD2 /* 0xff on equal bytes. */
- addi rNEG, rBITDIF, 1
- orc rNEG, rNEG, rBITDIF /* 0's below LS differing byte. */
- sldi rNEG, rNEG, 8 /* 1's above LS differing byte. */
- andc rWORD1, rWORD1, rNEG /* mask off MS bytes. */
- andc rWORD2, rWORD2, rNEG
- xor. rBITDIF, rWORD1, rWORD2
- sub rRTN, rWORD1, rWORD2
- blt L(highbit)
- sradi rRTN, rRTN, 63
- ori rRTN, rRTN, 1
- blr
-L(highbit):
- sradi rRTN, rWORD2, 63
- ori rRTN, rRTN, 1
- blr
-
-#else
-L(endstring):
- and rTMP,r7F7F,rWORD1
- beq cr1,L(equal)
- add rTMP,rTMP,r7F7F
- xor. rBITDIF,rWORD1,rWORD2
- andc rNEG,rNEG,rTMP
- blt L(highbit)
- cntlzd rBITDIF,rBITDIF
- cntlzd rNEG,rNEG
- addi rNEG,rNEG,7
- cmpd cr1,rNEG,rBITDIF
- sub rRTN,rWORD1,rWORD2
- blt cr1,L(equal)
- sradi rRTN,rRTN,63 /* must return an int. */
- ori rRTN,rRTN,1
- blr
-L(equal):
- li rRTN,0
- blr
-
-L(different):
- ld rWORD1,-8(rSTR1)
- xor. rBITDIF,rWORD1,rWORD2
- sub rRTN,rWORD1,rWORD2
- blt L(highbit)
- sradi rRTN,rRTN,63
- ori rRTN,rRTN,1
- blr
-L(highbit):
- sradi rRTN,rWORD2,63
- ori rRTN,rRTN,1
- blr
-#endif
-
-/* Oh well. In this case, we just do a byte-by-byte comparison. */
- .align 4
-L(tail):
- and. rTMP,rTMP,rNEG
- cmpd cr1,rWORD1,rWORD2
- bne L(endstring)
- addi rSTR1,rSTR1,8
- bne cr1,L(different)
- addi rSTR2,rSTR2,8
- cmpldi cr1,rN,0
-L(unaligned):
- mtctr rN
- ble cr1,L(ux)
-L(uz):
- lbz rWORD1,0(rSTR1)
- lbz rWORD2,0(rSTR2)
- .align 4
-L(u1):
- cmpdi cr1,rWORD1,0
- bdz L(u4)
- cmpd rWORD1,rWORD2
- beq cr1,L(u4)
- bne L(u4)
- lbzu rWORD3,1(rSTR1)
- lbzu rWORD4,1(rSTR2)
- cmpdi cr1,rWORD3,0
- bdz L(u3)
- cmpd rWORD3,rWORD4
- beq cr1,L(u3)
- bne L(u3)
- lbzu rWORD1,1(rSTR1)
- lbzu rWORD2,1(rSTR2)
- cmpdi cr1,rWORD1,0
- bdz L(u4)
- cmpd rWORD1,rWORD2
- beq cr1,L(u4)
- bne L(u4)
- lbzu rWORD3,1(rSTR1)
- lbzu rWORD4,1(rSTR2)
- cmpdi cr1,rWORD3,0
- bdz L(u3)
- cmpd rWORD3,rWORD4
- beq cr1,L(u3)
- bne L(u3)
- lbzu rWORD1,1(rSTR1)
- lbzu rWORD2,1(rSTR2)
- b L(u1)
-
-L(u3): sub rRTN,rWORD3,rWORD4
- blr
-L(u4): sub rRTN,rWORD1,rWORD2
- blr
-L(ux):
- li rRTN,0
- blr
-END (STRNCMP)
-libc_hidden_builtin_def (strncmp)
diff --git a/sysdeps/powerpc/powerpc64/strncmp.S b/sysdeps/powerpc/powerpc64/strncmp.S
deleted file mode 100644
index 40a230242cbdf733..0000000000000000
--- a/sysdeps/powerpc/powerpc64/strncmp.S
+++ /dev/null
@@ -1,210 +0,0 @@
-/* Optimized strcmp implementation for PowerPC64.
- Copyright (C) 2003-2021 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 <sysdep.h>
-
-/* See strlen.s for comments on how the end-of-string testing works. */
-
-/* int [r3] strncmp (const char *s1 [r3], const char *s2 [r4], size_t size [r5]) */
-
-#ifndef STRNCMP
-# define STRNCMP strncmp
-#endif
-
-ENTRY_TOCLESS (STRNCMP, 4)
- CALL_MCOUNT 3
-
-#define rTMP2 r0
-#define rRTN r3
-#define rSTR1 r3 /* first string arg */
-#define rSTR2 r4 /* second string arg */
-#define rN r5 /* max string length */
-#define rWORD1 r6 /* current word in s1 */
-#define rWORD2 r7 /* current word in s2 */
-#define rFEFE r8 /* constant 0xfefefefefefefeff (-0x0101010101010101) */
-#define r7F7F r9 /* constant 0x7f7f7f7f7f7f7f7f */
-#define rNEG r10 /* ~(word in s1 | 0x7f7f7f7f7f7f7f7f) */
-#define rBITDIF r11 /* bits that differ in s1 & s2 words */
-#define rTMP r12
-
- dcbt 0,rSTR1
- or rTMP, rSTR2, rSTR1
- lis r7F7F, 0x7f7f
- dcbt 0,rSTR2
- clrldi. rTMP, rTMP, 61
- cmpldi cr1, rN, 0
- lis rFEFE, -0x101
- bne L(unaligned)
-/* We are doubleword aligned so set up for two loops. first a double word
- loop, then fall into the byte loop if any residual. */
- srdi. rTMP, rN, 3
- clrldi rN, rN, 61
- addi rFEFE, rFEFE, -0x101
- addi r7F7F, r7F7F, 0x7f7f
- cmpldi cr1, rN, 0
- beq L(unaligned)
-
- mtctr rTMP /* Power4 wants mtctr 1st in dispatch group. */
- ld rWORD1, 0(rSTR1)
- ld rWORD2, 0(rSTR2)
- sldi rTMP, rFEFE, 32
- insrdi r7F7F, r7F7F, 32, 0
- add rFEFE, rFEFE, rTMP
- b L(g1)
-
-L(g0):
- ldu rWORD1, 8(rSTR1)
- bne- cr1, L(different)
- ldu rWORD2, 8(rSTR2)
-L(g1): add rTMP, rFEFE, rWORD1
- nor rNEG, r7F7F, rWORD1
- bdz L(tail)
- and. rTMP, rTMP, rNEG
- cmpd cr1, rWORD1, rWORD2
- beq+ L(g0)
-
-/* OK. We've hit the end of the string. We need to be careful that
- we don't compare two strings as different because of gunk beyond
- the end of the strings... */
-
-#ifdef __LITTLE_ENDIAN__
-L(endstring):
- addi rTMP2, rTMP, -1
- beq cr1, L(equal)
- andc rTMP2, rTMP2, rTMP
- rldimi rTMP2, rTMP2, 1, 0
- and rWORD2, rWORD2, rTMP2 /* Mask off gunk. */
- and rWORD1, rWORD1, rTMP2
- cmpd cr1, rWORD1, rWORD2
- beq cr1, L(equal)
- xor rBITDIF, rWORD1, rWORD2 /* rBITDIF has bits that differ. */
- neg rNEG, rBITDIF
- and rNEG, rNEG, rBITDIF /* rNEG has LS bit that differs. */
- cntlzd rNEG, rNEG /* bitcount of the bit. */
- andi. rNEG, rNEG, 56 /* bitcount to LS byte that differs. */
- sld rWORD1, rWORD1, rNEG /* shift left to clear MS bytes. */
- sld rWORD2, rWORD2, rNEG
- xor. rBITDIF, rWORD1, rWORD2
- sub rRTN, rWORD1, rWORD2
- blt- L(highbit)
- sradi rRTN, rRTN, 63 /* must return an int. */
- ori rRTN, rRTN, 1
- blr
-L(equal):
- li rRTN, 0
- blr
-
-L(different):
- ld rWORD1, -8(rSTR1)
- xor rBITDIF, rWORD1, rWORD2 /* rBITDIF has bits that differ. */
- neg rNEG, rBITDIF
- and rNEG, rNEG, rBITDIF /* rNEG has LS bit that differs. */
- cntlzd rNEG, rNEG /* bitcount of the bit. */
- andi. rNEG, rNEG, 56 /* bitcount to LS byte that differs. */
- sld rWORD1, rWORD1, rNEG /* shift left to clear MS bytes. */
- sld rWORD2, rWORD2, rNEG
- xor. rBITDIF, rWORD1, rWORD2
- sub rRTN, rWORD1, rWORD2
- blt- L(highbit)
- sradi rRTN, rRTN, 63
- ori rRTN, rRTN, 1
- blr
-L(highbit):
- sradi rRTN, rWORD2, 63
- ori rRTN, rRTN, 1
- blr
-
-#else
-L(endstring):
- and rTMP, r7F7F, rWORD1
- beq cr1, L(equal)
- add rTMP, rTMP, r7F7F
- xor. rBITDIF, rWORD1, rWORD2
- andc rNEG, rNEG, rTMP
- blt- L(highbit)
- cntlzd rBITDIF, rBITDIF
- cntlzd rNEG, rNEG
- addi rNEG, rNEG, 7
- cmpd cr1, rNEG, rBITDIF
- sub rRTN, rWORD1, rWORD2
- blt- cr1, L(equal)
- sradi rRTN, rRTN, 63 /* must return an int. */
- ori rRTN, rRTN, 1
- blr
-L(equal):
- li rRTN, 0
- blr
-
-L(different):
- ld rWORD1, -8(rSTR1)
- xor. rBITDIF, rWORD1, rWORD2
- sub rRTN, rWORD1, rWORD2
- blt- L(highbit)
- sradi rRTN, rRTN, 63
- ori rRTN, rRTN, 1
- blr
-L(highbit):
- sradi rRTN, rWORD2, 63
- ori rRTN, rRTN, 1
- blr
-#endif
-
-/* Oh well. In this case, we just do a byte-by-byte comparison. */
- .align 4
-L(tail):
- and. rTMP, rTMP, rNEG
- cmpd cr1, rWORD1, rWORD2
- bne- L(endstring)
- addi rSTR1, rSTR1, 8
- bne- cr1, L(different)
- addi rSTR2, rSTR2, 8
- cmpldi cr1, rN, 0
-L(unaligned):
- mtctr rN /* Power4 wants mtctr 1st in dispatch group */
- bgt cr1, L(uz)
-L(ux):
- li rRTN, 0
- blr
- .align 4
-L(uz):
- lbz rWORD1, 0(rSTR1)
- lbz rWORD2, 0(rSTR2)
- nop
- b L(u1)
-L(u0):
- lbzu rWORD2, 1(rSTR2)
-L(u1):
- bdz L(u3)
- cmpdi cr1, rWORD1, 0
- cmpd rWORD1, rWORD2
- beq- cr1, L(u3)
- lbzu rWORD1, 1(rSTR1)
- bne- L(u2)
- lbzu rWORD2, 1(rSTR2)
- bdz L(u3)
- cmpdi cr1, rWORD1, 0
- cmpd rWORD1, rWORD2
- bne- L(u3)
- lbzu rWORD1, 1(rSTR1)
- bne+ cr1, L(u0)
-
-L(u2): lbzu rWORD1, -1(rSTR1)
-L(u3): sub rRTN, rWORD1, rWORD2
- blr
-END (STRNCMP)
-libc_hidden_builtin_def (strncmp)