Displaying 2 results from an estimated 2 matches for "pslldq".
2016 Aug 12
4
Invoke loop vectorizer
...t;
> [dannyb at dannyb-macbookpro3 11:37:20] ~ :) $ clang -O3 test.c -c
> -save-temps
> [dannyb at dannyb-macbookpro3 11:38:28] ~ :) $ pcregrep -i "^\s*p"
> test.s|less
> pushq %rbp
> pshufd $68, %xmm0, %xmm0 ## xmm0 = xmm0[0,1,0,1]
> pslldq $8, %xmm1 ## xmm1 =
> zero,zero,zero,zero,zero,zero,zero,zero,xmm1[0,1,2,3,4,5,6,7]
> pshufd $68, %xmm3, %xmm3 ## xmm3 = xmm3[0,1,0,1]
> paddq %xmm1, %xmm3
> pshufd $78, %xmm3, %xmm4 ## xmm4 = xmm3[2,3,0,1]
> punpckldq...
2016 Aug 12
2
Invoke loop vectorizer
Hi Daniel,
I increased the size of your test to be 128 but -stats still shows no loop
optimized...
Xiaochu
On Aug 12, 2016 11:11 AM, "Daniel Berlin" <dberlin at dberlin.org> wrote:
> It's not possible to know that A and B don't alias in this example. It's
> almost certainly not profitable to add a runtime check given the size of
> the loop.
>
>
>