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| author | Lang Hames <lhames@gmail.com> | 2013-01-31 20:23:43 +0000 |
|---|---|---|
| committer | Lang Hames <lhames@gmail.com> | 2013-01-31 20:23:43 +0000 |
| commit | dd47804394881b4af75fa62edd88c9d45570ab9f (patch) | |
| tree | 56a0343cb9b6d4d59c3054356cf311cd610d3f0c /llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | |
| parent | 53f3f9f0cbc3688a9ed77b185b70c2ef608d4481 (diff) | |
| download | bcm5719-llvm-dd47804394881b4af75fa62edd88c9d45570ab9f.tar.gz bcm5719-llvm-dd47804394881b4af75fa62edd88c9d45570ab9f.zip | |
When lowering memcpys to loads and stores, make sure we don't promote alignments
past the natural stack alignment.
llvm-svn: 174085
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index b672926e9d3..57241227d9e 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -3561,6 +3561,15 @@ static SDValue getMemcpyLoadsAndStores(SelectionDAG &DAG, DebugLoc dl, if (DstAlignCanChange) { Type *Ty = MemOps[0].getTypeForEVT(*DAG.getContext()); unsigned NewAlign = (unsigned) TLI.getDataLayout()->getABITypeAlignment(Ty); + + // Don't promote to an alignment that would require dynamic stack + // realignment. + const TargetRegisterInfo *TRI = MF.getTarget().getRegisterInfo(); + if (!TRI->needsStackRealignment(MF)) + while (NewAlign > Align && + TLI.getDataLayout()->exceedsNaturalStackAlignment(NewAlign)) + NewAlign /= 2; + if (NewAlign > Align) { // Give the stack frame object a larger alignment if needed. if (MFI->getObjectAlignment(FI->getIndex()) < NewAlign) |
