Displaying 2 results from an estimated 2 matches for "str_ind_ptr_inc".
2013 Oct 23
0
[LLVMdev] First attempt at recognizing pointer reduction
...t can't find the array bounds.
Yes because we have to teach the vectorizer about pointer induction variables that stride for your example.
Your code - as far as I can reconstruct it from memory - looks something like
preheader:
loop:
%strided_induction_pointer = phi [preheader, %b], [loop, %str_ind_ptr_inc]
= load %strided_induction_pointer
%b_1 = gep %strided_induction_pointer, 1
… = load %b_1
%b_2 = gep %strided_induction_pointer, 2
… = load %b_2
%str_ind_ptr_inc = gep %strided_induction_pointer, 3 // Induction variable that strides by 3
%cmp = …
br %cmp, loop, exit
exit:
%stride...
2013 Oct 23
2
[LLVMdev] First attempt at recognizing pointer reduction
On 23 October 2013 16:05, Arnold Schwaighofer <aschwaighofer at apple.com>wrote:
> In the examples you gave there are no reduction variables in the loop
> vectorizer’s sense. But, they all have memory accesses that are strided.
>
This is what I don't get. As far as I understood, a reduction variable is
the one that aggregates the computation done by the loop, and is used