diff options
| author | Dylan McKay <me@dylanmckay.io> | 2017-12-09 06:45:36 +0000 |
|---|---|---|
| committer | Dylan McKay <me@dylanmckay.io> | 2017-12-09 06:45:36 +0000 |
| commit | 80463fe64dec84e92764f9a796870f3be404455d (patch) | |
| tree | 2d6e20d9dacd0d09b2c39bac665e5eb02c9bd79c /llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | |
| parent | aae5b6907988f2ef48f242a3fc6e02761a967fd8 (diff) | |
| download | bcm5719-llvm-80463fe64dec84e92764f9a796870f3be404455d.tar.gz bcm5719-llvm-80463fe64dec84e92764f9a796870f3be404455d.zip | |
Relax unaligned access assertion when type is byte aligned
Summary:
This relaxes an assertion inside SelectionDAGBuilder which is overly
restrictive on targets which have no concept of alignment (such as AVR).
In these architectures, all types are aligned to 8-bits.
After this, LLVM will only assert that accesses are aligned on targets
which actually require alignment.
This patch follows from a discussion on llvm-dev a few months ago
http://llvm.1065342.n5.nabble.com/llvm-dev-Unaligned-atomic-load-store-td112815.html
Reviewers: bogner, nemanjai, joerg, efriedma
Reviewed By: efriedma
Subscribers: efriedma, cactus, llvm-commits
Differential Revision: https://reviews.llvm.org/D39946
llvm-svn: 320243
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index f3addf05566..2dc9a728b65 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -4138,7 +4138,8 @@ void SelectionDAGBuilder::visitAtomicLoad(const LoadInst &I) { const TargetLowering &TLI = DAG.getTargetLoweringInfo(); EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); - if (I.getAlignment() < VT.getStoreSize()) + if (!TLI.supportsUnalignedAtomics() && + I.getAlignment() < VT.getStoreSize()) report_fatal_error("Cannot generate unaligned atomic load"); MachineMemOperand *MMO = |
