[PATCH] D16156: Proper handling of diamond-like cases in if-conversion

[Krzysztof Parzyszek via llvm-commits]

kparzysz added a comment.

The 4th statement will return if TT is null (actually both TT and FT), and both branches are analyzable.  You are right---returns are not analyzable, but this condition is not triggered.  The AnalyzeBranch from Hexagon does not differ in that respect from that from other targets.

I have tried other backends, but I couldn't get just the right optimizations to kick in.  Both function calls need to be tail calls, and a jump table needs to be created.  Moreover, the block with the jump table branch needs to be a target of a conditional branch that will be recognized as a diamond by the if converter.  For other backends, the code never looked right enough to trigger this condition, but I don't think there is anything Hexagon-specific (except the testcase itself).


Repository:
  rL LLVM

http://reviews.llvm.org/D16156