[Bug middle-end/30442] Expanded array initialization can use memset builtin function

[irar at il dot ibm dot com]

------- Comment #5 from irar at il dot ibm dot com  2008-03-13 06:51 -------
(In reply to comment #4)
> This still happens on mainline.
> 
> I wonder if vectorizer infrastructure can be re-used here to detect unrolled
> and looped version of memset. In addition to loop that can be "vectorized", we
> have something resembling "vectorization" of straight code.

This code can be vectorized with basic block SLP, which is not implemented yet
(currently only SLP in loops is implemented).

> And looking at comment #3, the rewards from real-world code look really
> promising.
> 
However, in comment #3 there is a loop:

               :  MALLOC(visited, int, d->tindex);
 48796 16.2440 :  for (i = 0; i < d->tindex; ++i)
 94442 31.4394 :    visited[i] = 0;

There was an effort to replace such loops with calls to builtins -
http://gcc.gnu.org/ml/gcc-patches/2007-07/msg00054.html.

Ira


-- 

irar at il dot ibm dot com changed:

           What    |Removed                     |Added
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                 CC|                            |irar at il dot ibm dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30442