Summary:
This patch fixes a bug that originated from passing a virtual exit block (nullptr) to `MachinePostDominatorTee::findNearestCommonDominator` and resulted in assertion failures inside its callee. It also applies a small cleanup to the class.
The patch introduces a new function in PDT that given a list of `MachineBasicBlock`s finds their NCD. The new overload of `findNearestCommonDominator` handles virtual root correctly.
Note that similar handling of virtual root nodes is not necessary in (forward) `DominatorTree`s, as right now they don't use virtual roots.
Reviewers: tstellar, tpr, nhaehnle, arsenm, NutshellySima, grosser, hliao
Reviewed By: hliao
Subscribers: hliao, kzhuravl, jvesely, wdng, yaxunl, dstuttard, t-tye, hiraditya, llvm-commits
Tags: #amdgpu, #llvm
Differential Revision: https://reviews.llvm.org/D67974
llvm-svn: 372874
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
DominatorTreeBase used to have IsPostDominators (bool) member to indicate if the tree is a dominator or a postdominator tree. This made it possible to switch between the two 'modes' at runtime, but it isn't used in practice anywhere.
This patch makes IsPostDominator a template argument. This way, it is easier to switch between different algorithms at compile-time based on this argument and design external utilities around it. It also makes it impossible to incidentally assign a postdominator tree to a dominator tree (and vice versa), and to further simplify template code in GenericDominatorTreeConstruction.
Reviewers: dberlin, sanjoy, davide, grosser
Reviewed By: dberlin
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35315
llvm-svn: 308040