[PATCH] D17288: [CodeGenPrepare] Do select to branch transform when cmp's operand is expensive.

[Sanjay Patel via llvm-commits]

spatel added subscribers: hfinkel, zansari, joker.eph, bkramer, jmolloy.
spatel added a comment.

[ cc'ing people who are subscribed to http://reviews.llvm.org/D16836 ]

I thought there was agreement that it is better to handle this at a later stage of compilation. This patch is going to form a branch for any target where the compare operand is expensive, but this hurts SelectionDAG because of its block-level scope.

This isn't the same as sinking a speculatively executed expensive op - in this case, we have to execute the expensive op regardless of the comparison result. Am I not understanding the motivation?


http://reviews.llvm.org/D17288