summaryrefslogtreecommitdiffstats
path: root/llvm/test/Transforms/LoopUnroll/tripcount-overflow.ll
Commit message (Collapse)AuthorAgeFilesLines
* [LoopUnroll] Switch the default value of -unroll-runtime-epilog back to its ↵Michael Zolotukhin2016-08-021-1/+1
| | | | | | | | | | original value. As agreed in post-commit review of r265388, I'm switching the flag to its original value until the 90% runtime performance regression on SingleSource/Benchmarks/Stanford/Bubblesort is addressed. llvm-svn: 277524
* The patch fixes PR27392.Evgeny Stupachenko2016-04-271-9/+21
| | | | | | | | | | | | | | | | | Summary: It is incorrect to compare TripCount (which is BECount + 1) with extraiters (or Count) to check if we should enter unrolled loop or not, because TripCount can potentially overflow (when BECount is max unsigned integer). While comparing BECount with (Count - 1) is overflow safe and therefore correct. Reviewer: hfinkel Differential Revision: http://reviews.llvm.org/D19256 From: Evgeny Stupachenko <evstupac@gmail.com> llvm-svn: 267662
* Adds the ability to use an epilog remainder loop during loop unrolling and makesDavid L Kreitzer2016-04-051-5/+5
| | | | | | | | | | this the default behavior. Patch by Evgeny Stupachenko (evstupac@gmail.com). Differential Revision: http://reviews.llvm.org/D18158 llvm-svn: 265388
* Partial fix for bug 22589Sanjoy Das2015-02-181-11/+18
| | | | | | | | | | | Don't spend the entire iteration space in the scalar loop prologue if computing the trip count overflows. This change also gets rid of the backedge check in the prologue loop and the extra check for overflowing trip-count. Differential Revision: http://reviews.llvm.org/D7715 llvm-svn: 229731
* Fix a trip-count overflow issue in LoopUnroll.Michael Zolotukhin2014-11-201-0/+30
Currently LoopUnroll generates a prologue loop before the main loop body to execute first N%UnrollFactor iterations. Also, this loop is used if trip-count can overflow - it's determined by a runtime check. However, we've been mistakenly optimizing this loop to a linear code for UnrollFactor = 2, not taking into account that it also serves as a safe version of the loop if its trip-count overflows. llvm-svn: 222451
OpenPOWER on IntegriCloud