5 Commits

Author	SHA1	Message	Date
Florian Hahn	d98fc62ae6	[SimplifyCFG] Keep !dgb metadata of moved instruction, if they match. ... Currently SimplifyCFG drops the debug locations of 'bonus' instructions. Such instructions are moved before the first branch. The reason for the current behavior is that this could lead to surprising debug stepping, if the block that's folded is dead. In case the first branch and the instructions to be folded have the same debug location, this shouldn't be an issue and we can keep the debug location. Reviewed By: vsk Differential Revision: https://reviews.llvm.org/D93662	2021-01-09 19:15:16 +00:00
Roman Lebedev	c043f5055e	[SimplifyCFG] Teach FoldBranchToCommonDest() to preserve DomTree, part 1 ... ... for conditional branch case	2020-12-20 00:18:36 +03:00
Roman Lebedev	b43b77ff9b	[NFCI][SimlifyCFG] simplifyOnce(): also perform DomTree validation ... And that exposes that a number of tests don't *actually* manage to maintain DomTree validity, which is inline with my observations. Once again, SimlifyCFG pass currently does not require/preserve DomTree by default, so this is effectively NFC.	2020-12-20 00:18:32 +03:00
Roman Lebedev	164e0847a5	[SimplifyCFG] DeleteDeadBlock() already knows how to preserve DomTree ... ... so just ensure that we pass DomTreeUpdater it into it. Fixes DomTree preservation for a large number of tests, all of which are marked as such so that they do not regress.	2020-12-18 00:37:21 +03:00
Davide Italiano	8cdd2a158c	[SimplifyCFG] Update debug location when folding branch to common destination ... Sometimes a dead block gets folded and the debug information is still retained. This manifests as jumpy stepping in lldb, see the bugzilla PR for an end-to-end C testcase. Fixes https://bugs.llvm.org/show_bug.cgi?id=46008 Differential Revision: https://reviews.llvm.org/D82062	2020-06-18 12:33:32 -07:00