Commit Graph

3 Commits

Author SHA1 Message Date
Congzhe Cao ce2db9005d [LoopInterchange] Fix transformation bugs in loop interchange
After loop interchange, the (old) outer loop header should not jump to
the `LoopExit`. Note that the old outer loop becomes the new inner loop
after interchange. If we branched to `LoopExit` then after interchange
we would jump directly from the (new) inner loop header to `LoopExit`
without executing the rest of outer loop.

This patch modifies adjustLoopBranches() such that the old outer
loop header (which becomes the new inner loop header) jumps to the
old inner loop latch which becomes the new outer loop latch after
interchange.

Reviewed By: bmahjour

Differential Revision: https://reviews.llvm.org/D98475
2021-04-08 14:58:13 -04:00
Congzhe Cao 593cb46550 Revert "[LoopInterchange] Fix transformation bugs in loop interchange"
This reverts commit 6ec68bd815d00c1eec2a6b9766452554f0e6cb61.
2021-04-07 21:17:30 -04:00
CongzheUalberta f5645ea65f [LoopInterchange] Fix transformation bugs in loop interchange
After loop interchange, the (old) outer loop header should not jump to
`LoopExit`. Note that the old outer loop becomes the new inner loop
after interchange. If we branched to `LoopExit` then after interchange
we would jump directly from the (new) inner loop header to `LoopExit`
without executing the rest of (new) outer loop.

This patch modifies adjustLoopBranches() such that the old outer
loop header (which becomes the new inner loop header) jumps to the
old inner loop latch which becomes the new outer loop latch after
interchange.

Reviewed By: bmahjour

Differential Revision: https://reviews.llvm.org/D98475
2021-04-07 20:55:44 -04:00