summaryrefslogtreecommitdiffstats
path: root/llvm/test/Transforms/LoopFusion/simple.ll
Commit message (Collapse)AuthorAgeFilesLines
* [LoopFusion] Move instructions from FC0.Latch to FC1.Latch.Whitney Tsang2019-12-171-14/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary:This PR move instructions from FC0.Latch bottom up to the beginning of FC1.Latch as long as they are proven safe. To illustrate why this is beneficial, let's consider the following example: Before Fusion: header1: br header2 header2: br header2, latch1 latch1: br header1, preheader3 preheader3: br header3 header3: br header4 header4: br header4, latch3 latch3: br header3, exit3 After Fusion (before this PR): header1: br header2 header2: br header2, latch1 latch1: br header3 header3: br header4 header4: br header4, latch3 latch3: br header1, exit3 Note that preheader3 is removed during fusion before this PR. Notice that we cannot fuse loop2 with loop4 as there exists block latch1 in between. This PR move instructions from latch1 to beginning of latch3, and remove block latch1. LoopFusion is now able to fuse loop nest recursively. After Fusion (after this PR): header1: br header2 header2: br header3 header3: br header4 header4: br header2, latch3 latch3: br header1, exit3 Reviewer: kbarton, jdoerfert, Meinersbur, dmgreen, fhahn, hfinkel, bmahjour, etiotto Reviewed By: kbarton, Meinersbur Subscribers: hiraditya, llvm-commits Tag: LLVM Differential Revision: https://reviews.llvm.org/D71165
* [LoopFusion] Restrict loop fusion to rotated loops.Kit Barton2019-12-161-179/+130
| | | | | | | | | | | | | | | | Summary: This patch restricts loop fusion to only consider rotated loops as valid candidates. This simplifies the analysis and transformation and aligns with other loop optimizations. Reviewers: jdoerfert, Meinersbur, dmgreen, etiotto, Whitney, fhahn, hfinkel Reviewed By: Meinersbur Subscribers: ormris, hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D71025
* Add basic loop fusion pass.Kit Barton2019-04-171-0/+317
| | | | | | | | | | | | | | | | | | | | This patch adds a basic loop fusion pass. It will fuse loops that conform to the following 4 conditions: 1. Adjacent (no code between them) 2. Control flow equivalent (if one loop executes, the other loop executes) 3. Identical bounds (both loops iterate the same number of iterations) 4. No negative distance dependencies between the loop bodies. The pass does not make any changes to the IR to create opportunities for fusion. Instead, it checks if the necessary conditions are met and if so it fuses two loops together. The pass has not been added to the pass pipeline yet, and thus is not enabled by default. It can be run stand alone using the -loop-fusion option. Differential Revision: https://reviews.llvm.org/D55851 llvm-svn: 358607
* Revert "Add basic loop fusion pass." Per request.Eric Christopher2019-04-171-317/+0
| | | | | | This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda. llvm-svn: 358553
* Revert "Temporarily Revert "Add basic loop fusion pass.""Eric Christopher2019-04-171-0/+317
| | | | | | | | The reversion apparently deleted the test/Transforms directory. Will be re-reverting again. llvm-svn: 358552
* Temporarily Revert "Add basic loop fusion pass."Eric Christopher2019-04-171-317/+0
| | | | | | | | As it's causing some bot failures (and per request from kbarton). This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda. llvm-svn: 358546
* Add basic loop fusion pass.Kit Barton2019-04-171-0/+317
This patch adds a basic loop fusion pass. It will fuse loops that conform to the following 4 conditions: 1. Adjacent (no code between them) 2. Control flow equivalent (if one loop executes, the other loop executes) 3. Identical bounds (both loops iterate the same number of iterations) 4. No negative distance dependencies between the loop bodies. The pass does not make any changes to the IR to create opportunities for fusion. Instead, it checks if the necessary conditions are met and if so it fuses two loops together. The pass has not been added to the pass pipeline yet, and thus is not enabled by default. It can be run stand alone using the -loop-fusion option. Phabricator: https://reviews.llvm.org/D55851 llvm-svn: 358543
OpenPOWER on IntegriCloud