diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc32/power7/memchr.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc32/power7/memchr.S | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/sysdeps/powerpc/powerpc32/power7/memchr.S b/sysdeps/powerpc/powerpc32/power7/memchr.S index 318168b4cf..ec78709c35 100644 --- a/sysdeps/powerpc/powerpc32/power7/memchr.S +++ b/sysdeps/powerpc/powerpc32/power7/memchr.S @@ -1,5 +1,5 @@ /* Optimized memchr implementation for PowerPC32/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. @@ -26,7 +26,16 @@ ENTRY (__memchr) dcbt 0,r3 clrrwi r8,r3,2 insrwi r4,r4,8,16 /* Replicate byte to word. */ - 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 + or r7,r7,r9 + insrwi r4,r4,16,0 cmplwi r5,16 li r9, -1 |