Makes __stpncpy_power8 call __memset_power8 directly rather than via an
IFUNC. Fixes a missing _mcount, and removes some redundant NOPS. The
*_is_local defines are also used in a followup patch.
* sysdeps/powerpc/powerpc64/multiarch/strncpy-power7.S: Define
MEMSET_is_local.
* sysdeps/powerpc/powerpc64/multiarch/strncpy-power8.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/stpncpy-power8.S: Likewise.
Define MEMSET.
* sysdeps/powerpc/powerpc64/multiarch/strstr-power7.S: Define
STRLEN_is_local, STRNLEN_is_local, and STRCHR_is_local.
* sysdeps/powerpc/powerpc64/power7/strstr.S: Likewise. Don't add
nop after local calls.
* sysdeps/powerpc/powerpc64/power7/strncpy.S: Define MEMSET_is_local.
Don't add nop after local call.
* sysdeps/powerpc/powerpc64/power8/strncpy.S: Likewise. Add missing
CALL_MCOUNT.
Clean up the IFUNC implementations for powerpc in order to remove
unneeded macro definitions.
Tested on ppc64le with and without --disable-multi-arch flag.
* sysdeps/powerpc/powerpc64/multiarch/stpcpy-power8.S: Define the
implementation-specific function name and remove unneeded macros
definition.
* sysdeps/powerpc/powerpc64/multiarch/stpncpy-power7.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/stpncpy-power8.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/strcpy-power8.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/strncpy-power7.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/strncpy-power8.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/strncpy.S: Set a default
function name if not defined.
* sysdeps/powerpc/powerpc64/power8/strcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/power8/strncpy.S: Likewise.
The optimization is achieved by following techniques:
> data alignment [gain from aligned memory access on read/write]
> POWER7 gains performance with loop unrolling/unwinding
[gain by reduction of branch penalty].
> zero padding done by calling optimized memset
