RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-26 12:43:36 +01:00
Code Issues Projects Releases Wiki Activity

[LV] Use ScalarEvolution::getURemExpr to reduce duplication.

Browse Source 
ScalarEvolution should be able to handle both constant and variable trip
counts using getURemExpr, so we do not have to handle them separately.

This is a small simplification of a56280094e08.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D93677
This commit is contained in:
Florian Hahn 2020-12-22 14:44:09 +00:00
parent e6292b9b96
commit 4cdccd0b93
1 changed files with 3 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
lib/Transforms/Vectorize/LoopVectorize.cpp
View File

@ -5506,20 +5506,15 @@ LoopVectorizationCostModel::computeMaxVF(ElementCount UserVF, unsigned UserIC) {
"MaxVF must be a power of 2");
unsigned MaxVFtimesIC =
UserIC ? MaxVF.getFixedValue() * UserIC : MaxVF.getFixedValue();
if (TC > 0 && TC % MaxVFtimesIC == 0) {
// Accept MaxVF if we do not have a tail.
LLVM_DEBUG(dbgs() << "LV: No tail will remain for any chosen VF.\n");
return MaxVF;
}
// Avoid tail folding if the trip count is known to be a multiple of any VF we
// chose.
ScalarEvolution *SE = PSE.getSE();
const SCEV *BackedgeTakenCount = PSE.getBackedgeTakenCount();
const SCEV *ExitCount = SE->getAddExpr(
BackedgeTakenCount, SE->getOne(BackedgeTakenCount->getType()));
unsigned TCisMultipleOf = 1 << SE->GetMinTrailingZeros(ExitCount);
if (TCisMultipleOf % MaxVFtimesIC == 0) {
const SCEV *Rem = SE->getURemExpr(
ExitCount, SE->getConstant(BackedgeTakenCount->getType(), MaxVFtimesIC));
if (Rem->isZero()) {
// Accept MaxVF if we do not have a tail.
LLVM_DEBUG(dbgs() << "LV: No tail will remain for any chosen VF.\n");
return MaxVF;