| commit | 98a021fcbfe104f98c7b67c35af4bbbccc3c1b8f | |
| author | Stephen Tozer <stephen.tozer@sony.com> | |
| Fri, 3 Dec 2021 13:35:25 +0000 (3 13:35 +0000) | ||
| committer | Stephen Tozer <stephen.tozer@sony.com> | |
| Fri, 3 Dec 2021 15:30:05 +0000 (3 15:30 +0000) | ||
| tree | 29786b57fde1efa50f08e16e328b52e5ed44d595 | treesnapshot (tar.gz zip) |
| parent | ab0c5cea0b1a9a1227fea840184dd7b5983c22a5 | commitdiff |
[DebugInfo] Attempt to preserve more information during tail duplication
Prior to this patch, tail duplication handled debug info poorly -
specifically, debug instructions would be dropped instead of being set
undef, potentially extending the lifetimes of prior debug values that
should be killed. The pass was also very aggressive with dropping debug
info, dropping debug info even when the SSA value it referred to was
still present. This patch attempts to handle debug info more carefully,
checking to see whether each affected debug value can still be live,
setting it undef if not.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D106875
Prior to this patch, tail duplication handled debug info poorly -
specifically, debug instructions would be dropped instead of being set
undef, potentially extending the lifetimes of prior debug values that
should be killed. The pass was also very aggressive with dropping debug
info, dropping debug info even when the SSA value it referred to was
still present. This patch attempts to handle debug info more carefully,
checking to see whether each affected debug value can still be live,
setting it undef if not.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D106875