Chijun Sima 7a83b127de Teach the DominatorTree fallback to recalculation when applying updates to speedup JT (PR37929) ... Summary: This patch makes the dominatortree recalculate when applying updates with the size of the update vector larger than a threshold. Directly applying updates is usually slower than recalculating the whole domtree in this case. This patch fixes an issue which causes JT running slowly on some inputs. In bug 37929, the dominator tree is trying to apply 19,000+ updates several times, which takes several minutes. After this patch, the time used by DT.applyUpdates: | Input | Before (s) | After (s) | Speedup | | the 2nd Reproducer in 37929 | 297 | 0.15 | 1980x | | clang-5.0.0.0.bc | 9.7 | 4.3 | 2.26x | | clang-5.0.0.4.bc | 11.6 | 2.6 | 4.46x | Reviewers: kuhar, brzycki, trentxintong, davide, dmgreen, grosser Reviewed By: kuhar, brzycki Subscribers: kristina, llvm-commits Differential Revision: https://reviews.llvm.org/D53245 llvm-svn: 345353		2018-10-26 01:28:36 +00:00
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llvm	Teach the DominatorTree fallback to recalculation when applying updates to speedup JT (PR37929)	2018-10-26 01:28:36 +00:00
llvm-c	[TI removal] Update the C API for the move away from TerminatorInst.	2018-10-18 23:03:55 +00:00