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1 Commits

Author SHA1 Message Date
Akira Hatanaka bbd33f6766 [Branch probability] Recompute branch weights of tail-merged basic blocks.
BranchFolderPass was not correctly setting the basic block branch weights when
tail-merging created or merged blocks. This patch recomutes the weights of
tail-merged blocks using the following formula:

branch_weight(merged block to successor j) =
sum(block_frequency(bb) * branch_probability(bb -> j))

bb is a block that is in the set of merged blocks.

<rdar://problem/16256423>

llvm-svn: 215135
2014-08-07 19:30:13 +00:00