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| author | Justin Lebar <jlebar@google.com> | 2016-09-11 01:38:58 +0000 |
|---|---|---|
| committer | Justin Lebar <jlebar@google.com> | 2016-09-11 01:38:58 +0000 |
| commit | adbf09e8cfd3aa6bb104f45bf5f39e4e8578d2f8 (patch) | |
| tree | 462f51cead1ea3e5f264f3c84af6e5e94aceda72 /llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | |
| parent | 4fab7454c5480bc68732ba456bb3aff3ffdedfa0 (diff) | |
| download | bcm5719-llvm-adbf09e8cfd3aa6bb104f45bf5f39e4e8578d2f8.tar.gz bcm5719-llvm-adbf09e8cfd3aa6bb104f45bf5f39e4e8578d2f8.zip | |
[CodeGen] Split out the notions of MI invariance and MI dereferenceability.
Summary:
An IR load can be invariant, dereferenceable, neither, or both. But
currently, MI's notion of invariance is IR-invariant &&
IR-dereferenceable.
This patch splits up the notions of invariance and dereferenceability at
the MI level. It's NFC, so adds some probably-unnecessary
"is-dereferenceable" checks, which we can remove later if desired.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D23371
llvm-svn: 281151
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 249abb998e8..8783bb24dae 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -14280,6 +14280,8 @@ bool DAGCombiner::SimplifySelectOps(SDNode *TheSelect, SDValue LHS, MachineMemOperand::Flags MMOFlags = LLD->getMemOperand()->getFlags(); if (!RLD->isInvariant()) MMOFlags &= ~MachineMemOperand::MOInvariant; + if (!RLD->isDereferenceable()) + MMOFlags &= ~MachineMemOperand::MODereferenceable; if (LLD->getExtensionType() == ISD::NON_EXTLOAD) { // FIXME: Discards pointer and AA info. Load = DAG.getLoad(TheSelect->getValueType(0), SDLoc(TheSelect), |
