Commit Graph

2 Commits

Author SHA1 Message Date
Igor Laevsky 1ef06559f4 [RS4GC] Strip noalias attribute after statepoint rewrite
We should remove noalias along with dereference and dereference_or_null attributes 
because statepoint could potentially touch the entire heap including noalias objects.

Differential Revision: http://reviews.llvm.org/D14032

llvm-svn: 251333
2015-10-26 19:06:01 +00:00
Sanjoy Das 353a19e13c [RewriteStatepointsForGC] Strip deref info after rewriting.
Summary:
Once a gc.statepoint has been rewritten to relocate live references, the
SSA values represent physical pointers instead of logical references.
Logical dereferencability does not imply physical dereferencability and
after RewriteStatepointsForGC has run any attributes that imply
dereferencability of the logical references need to be stripped.

This current approach is conservative, and can be made more precise
later if needed.  For starters, we need to strip dereferencable
attributes only from pointers that live in the GC address space.

Reviewers: reames, pgavlin

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10105

llvm-svn: 238883
2015-06-02 22:33:37 +00:00