cutils: Remove ppc buffer zero checking

For ppc64le, gcc6 does extremely poorly with the Altivec code.
Moreover, on POWER7 and POWER8, a hand-optimized Altivec version
turns out to be no faster than the revised integer version, and
therefore not worth the effort.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Richard Henderson 2016-08-29 11:46:20 -07:00 committed by Paolo Bonzini
parent 2250d3a293
commit 43ff5e01ec

View File

@ -94,31 +94,7 @@ buffer_zero_int(const void *buf, size_t len)
}
}
#if defined(__ALTIVEC__)
#include <altivec.h>
/* The altivec.h header says we're allowed to undef these for
* C++ compatibility. Here we don't care about C++, but we
* undef them anyway to avoid namespace pollution.
* altivec.h may redefine the bool macro as vector type.
* Reset it to POSIX semantics.
*/
#undef vector
#undef pixel
#undef bool
#define bool _Bool
#define DO_NONZERO(X) vec_any_ne(X, (__vector unsigned char){ 0 })
ACCEL_BUFFER_ZERO(buffer_zero_ppc, 128, __vector unsigned char, DO_NONZERO)
static bool select_accel_fn(const void *buf, size_t len)
{
uintptr_t ibuf = (uintptr_t)buf;
if (len % 128 == 0 && ibuf % sizeof(__vector unsigned char) == 0) {
return buffer_zero_ppc(buf, len);
}
return buffer_zero_int(buf, len);
}
#elif defined(CONFIG_AVX2_OPT) || (defined(CONFIG_CPUID_H) && defined(__SSE2__))
#if defined(CONFIG_AVX2_OPT) || (defined(CONFIG_CPUID_H) && defined(__SSE2__))
#include <cpuid.h>
/* Do not use push_options pragmas unnecessarily, because clang