On 5/28/2022 1:12 AM, Yu-Jen Chang wrote:
*** BLURB HERE ***
These patch series add an optimized "memchr()" for x86-64 and
USER-MODE LINUX (UML).
There exists an assemebly implementation for x86-32. However,
for x86-64, there isn't any optimized version. We implement word-wise
comparison so
On Sat, May 28, 2022 at 04:12:35PM +0800, Yu-Jen Chang wrote:
> The original assembly version of memchr() is implemented with
> the byte-wise comparing technique, which does not fully
> use 64-bits registers in x86_64 CPU. We use word-wide
> comparing so that 8 characters can be compared at the sa
Add x86_64-optimized memchr, which is 4x faster
than the original implementation, into um.
Signed-off-by: Yu-Jen Chang
Signed-off-by: Ching-Chun (Jim) Huang
---
arch/x86/um/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile
i
The original assembly version of memchr() is implemented with
the byte-wise comparing technique, which does not fully
use 64-bits registers in x86_64 CPU. We use word-wide
comparing so that 8 characters can be compared at the same time
on x86_64 CPU. First we align the input and then use word-wise
*** BLURB HERE ***
These patch series add an optimized "memchr()" for x86-64 and
USER-MODE LINUX (UML).
There exists an assemebly implementation for x86-32. However,
for x86-64, there isn't any optimized version. We implement word-wise
comparison so that 8 characters can be compared at the sam
