[PATCH] D17257: New utility class ReachingPhysDefs for post-ra analysis.

[Krzysztof Parzyszek via llvm-commits]

kparzysz added a comment.

Hi Quentin,
Currently, RDF is local to Hexagon and so only Hexagon passes use it.  There is one pass upstream and we have one more that hasn't yet been upstreamed.

What RDF does is that it connects defs to other related defs and to reached uses.  That provides ways to easily get reached uses for each def and reaching defs for each def and use.  We also have a pass that recalculates block live-ins using that information.

You can take a look at lib/Target/Hexagon/RDFGraph.h, there are comments at the beginning of the file that describe what it is.  The liveness is implemented in RDFLiveness.h/.cpp.


http://reviews.llvm.org/D17257