If dominator tree is not calculated or is invalidated, set corresponding
pointer in the pass state to nullptr. Such pointer value will indicate
that operations with dominator tree are not allowed. In particular, it
allows to skip verification for such pass state. The dominator tree is
not calculated if the machine dominator pass was skipped, it occures in
the case of entities with linkage available_externally.
The change fixes some test fails observed when expensive checks
are enabled.
Differential Revision: https://reviews.llvm.org/D29280
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296742 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r293033, per Danny's comment. In short, we require
domtrees to have roots at all times.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293075 91177308-0d34-0410-b5e6-96231b3b80d8
If dominator tree has no roots, the pass that calculates it is
likely to be skipped. It occures, for instance, in the case of
entities with linkage available_externally. Do not run tree
verification in such case.
Differential Revision: https://reviews.llvm.org/D28767
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293033 91177308-0d34-0410-b5e6-96231b3b80d8
Running tests with expensive checks enabled exhibits some problems with
verification of pass results.
First, the pass verification may require results of analysis that are not
available. For instance, verification of loop info requires results of dominator
tree analysis. A pass may be marked as conserving loop info but does not need to
be dependent on DominatorTreePass. When a pass manager tries to verify that loop
info is valid, it needs dominator tree, but corresponding analysis may be
already destroyed as no user of it remained.
Another case is a pass that is skipped. For instance, entities with linkage
available_externally do not need code generation and such passes are skipped for
them. In this case result verification must also be skipped.
To solve these problems this change introduces a special flag to the Pass
structure to mark passes that have valid results. If this flag is reset,
verifications dependent on the pass result are skipped.
Differential Revision: https://reviews.llvm.org/D27190
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291882 91177308-0d34-0410-b5e6-96231b3b80d8
to support C99 inline, GNU extern inline, etc. Related bugzilla's
include PR3517, PR3100, & PR2933. Nothing uses this yet, but it
appears to work.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68940 91177308-0d34-0410-b5e6-96231b3b80d8
