Alina Sbirlea 2493ab105d [SCEV] Add option to forget everything in SCEV. ... Summary: Create a method to forget everything in SCEV. Add a cl::opt and PassManagerBuilder option to use this in LoopUnroll. Motivation: Certain Halide applications spend a very long time compiling in forgetLoop, and prefer to forget everything and rebuild SCEV from scratch. Sample difference in compile time reduction: 21.04 to 14.78 using current ToT release build. Testcase showcasing this cannot be opensourced and is fairly large. The option disabled by default, but it may be desirable to enable by default. Evidence in favor (two difference runs on different days/ToT state): File Before (s) After (s) clang-9.bc 7267.91 6639.14 llvm-as.bc 194.12 194.12 llvm-dis.bc 62.50 62.50 opt.bc 1855.85 1857.53 File Before (s) After (s) clang-9.bc 8588.70 7812.83 llvm-as.bc 196.20 194.78 llvm-dis.bc 61.55 61.97 opt.bc 1739.78 1886.26 Reviewers: sanjoy Subscribers: mehdi_amini, jlebar, zzheng, javed.absar, dmgreen, jdoerfert, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D60144 llvm-svn: 358304		2019-04-12 19:16:07 +00:00
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IPO	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
Scalar	[MemorySSA & LoopPassManager] Add remaining book keeping [NFCI].	2019-02-12 23:48:02 +00:00
Utils	[SCEV] Add option to forget everything in SCEV.	2019-04-12 19:16:07 +00:00
Vectorize	Update files that were mistakenly added with the old file header to the	2019-02-11 08:07:38 +00:00
CMakeLists.txt	[VPlanRecipeBase] Add insertBefore helper.	2018-06-18 11:34:17 +00:00