[llvm-commits] vector widening patch

[Duncan Sands]

Hi,

> Here is a patch for vector widen.  In certain cases, it is more  
> profitable to widen a vector from an illegal type to a legal type  
> (e.g., v7i8 to v8i8) instead of scalarzing the vector.  This patch  
> implements that.  The default implementation is to widen if there is a  
> legal type that is wider than the illegal type and the vector has more  
> elements.  Any target can override the default logic and implement it  
> own policy.  Please let me know if you have any comments or concerns.

how about adding Widen to LegalizeAction, to make things uniform with
expand and promote.  Also, I think it would be better to do this in
LegalizeTypes [*] rather than in LegalizeDAG - it's the future, and
it's also much cleaner.

Ciao,

Duncan.

[*] Now that 2.4 is more or less done, I plan to push hard to finish
off LegalizeTypes (which is in pretty good shape except for vector
shuffle).