Now that MemorySSA keeps track of whether MemoryUses are optimized, use
getClobberingMemoryAccess() to check MemoryUse memory dependencies since
it should no longer be so expensive.
This is a follow-up change to https://reviews.llvm.org/D25881
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285080 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When using MemorySSA, re-optimize MemoryPhis when removing a store since
this may create MemoryPhis with all identical arguments.
Also, when using MemorySSA to check if two MemoryUses are reading from
the same version of the heap, use the defining access instead of calling
getClobberingAccess, since the latter can currently result in many more
AA calls. Once the MemorySSA use optimization tracking changes are
done, we can remove this limitation, which should result in more loads
being CSE'd.
Reviewers: dberlin
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D25881
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284984 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Use MemorySSA, if requested, to do less conservative memory dependency
checking.
This change doesn't enable the MemorySSA enhanced EarlyCSE in the
default pipelines, so should be NFC.
Reviewers: dberlin, sanjoy, reames, majnemer
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D19821
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280279 91177308-0d34-0410-b5e6-96231b3b80d8