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[Qemu-devel] [PATCH v3 8/9] cutils: Remove aarch64 buffer zero checking
From: |
Richard Henderson |
Subject: |
[Qemu-devel] [PATCH v3 8/9] cutils: Remove aarch64 buffer zero checking |
Date: |
Mon, 29 Aug 2016 11:46:19 -0700 |
The revised integer version is 4 times faster than the neon version
on an AppliedMicro Mustang. Even with hand scheduling and additional
unrolling I cannot make any neon version run as fast as the integer.
Signed-off-by: Richard Henderson <address@hidden>
---
util/bufferiszero.c | 15 ---------------
1 file changed, 15 deletions(-)
diff --git a/util/bufferiszero.c b/util/bufferiszero.c
index 7fcc8e1..6d13d7f 100644
--- a/util/bufferiszero.c
+++ b/util/bufferiszero.c
@@ -355,21 +355,6 @@ static bool select_accel_fn(const void *buf, size_t len)
return buffer_zero_int(buf, len);
}
-#elif defined(__aarch64__)
-#include "arm_neon.h"
-
-#define DO_NONZERO(X) (vgetq_lane_u64((X), 0) | vgetq_lane_u64((X), 1))
-ACCEL_BUFFER_ZERO(buffer_zero_neon, 128, uint64x2_t, 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(uint64x2_t) == 0) {
- return buffer_zero_neon(buf, len);
- }
- return buffer_zero_int(buf, len);
-}
-
#else
#define select_accel_fn buffer_zero_int
#endif
--
2.7.4
- [Qemu-devel] [PATCH v3 0/9] Improve buffer_is_zero, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 3/9] cutils: Export only buffer_is_zero, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 1/9] cutils: Move buffer_is_zero and subroutines to a new file, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 4/9] cutils: Rearrange buffer_is_zero acceleration, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 9/9] cutils: Remove ppc buffer zero checking, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 8/9] cutils: Remove aarch64 buffer zero checking,
Richard Henderson <=
- [Qemu-devel] [PATCH v3 6/9] cutils: Add generic prefetch, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 5/9] cutils: Add test for buffer_is_zero, Richard Henderson, 2016/08/29
- [Qemu-devel] [PATCH v3 7/9] cutils: Rewrite x86 buffer zero checking, Richard Henderson, 2016/08/29
- Re: [Qemu-devel] [PATCH v3 0/9] Improve buffer_is_zero, Paolo Bonzini, 2016/08/30