This is the mail archive of the mailing list for the GCC project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [autovect] [committed] vectorizer idiom recognition support andsaturating subtraction

This patch adds an analysis pass that searches for computation idioms in
the program. It is a tentative implementation, that invokes the
pattern-recognition pass from within the vectorizer, only on loops that are
candidate for vectorization. The pattern is replaced only if it can be
vectorized. We may want instead to invoke it as a general pass independent
of the vectorizer that searches for such idioms anywhere in the program (as
part of a tree-combine pass?).

Or of phiopt. In fact your patch looks like a different implementation of phiopt. I had a patch that built a COND_EXPR out of a phi and let fold recognize/simplify it. Maybe phiopt can become a special case of the tree-combine pass.

For the particular case of unsigned saturation, it may be worthwhile to recognize it in fold and (in case the optab does not have an entry for a particular mode) have different expansions of it depending on the BRANCH_COST.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]