diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc64/power7/memchr.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc64/power7/memchr.S | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/sysdeps/powerpc/powerpc64/power7/memchr.S b/sysdeps/powerpc/powerpc64/power7/memchr.S index 03f0d7c2dd..9ab5ab2099 100644 --- a/sysdeps/powerpc/powerpc64/power7/memchr.S +++ b/sysdeps/powerpc/powerpc64/power7/memchr.S @@ -1,5 +1,5 @@ /* Optimized memchr implementation for PowerPC64/POWER7 using cmpb insn. - Copyright (C) 2010-2016 Free Software Foundation, Inc. + Copyright (C) 2010-2018 Free Software Foundation, Inc. Contributed by Luis Machado <luisgpm@br.ibm.com>. This file is part of the GNU C Library. @@ -20,13 +20,27 @@ #include <sysdep.h> /* int [r3] memchr (char *s [r3], int byte [r4], int size [r5]) */ + +#ifndef MEMCHR +# define MEMCHR __memchr +#endif .machine power7 -ENTRY (__memchr) +ENTRY_TOCLESS (MEMCHR) CALL_MCOUNT 3 dcbt 0,r3 clrrdi r8,r3,3 insrdi r4,r4,8,48 - add r7,r3,r5 /* Calculate the last acceptable address. */ + + /* Calculate the last acceptable address and check for possible + addition overflow by using satured math: + r7 = r3 + r5 + r7 |= -(r7 < x) */ + add r7,r3,r5 + subfc r6,r3,r7 + subfe r9,r9,r9 + extsw r6,r9 + or r7,r7,r6 + insrdi r4,r4,16,32 cmpldi r5,32 li r9, -1 @@ -180,6 +194,6 @@ L(small_range): bne cr6,L(done) blr -END (__memchr) +END (MEMCHR) weak_alias (__memchr, memchr) libc_hidden_builtin_def (memchr) |