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author | Hal Finkel <hfinkel@anl.gov> | 2013-07-18 04:28:21 +0000 |
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committer | Hal Finkel <hfinkel@anl.gov> | 2013-07-18 04:28:21 +0000 |
commit | aad2a72c285a48e34d89ba69d24eb624f2b09b0e (patch) | |
tree | cbc687b35049ae985b9b34a1a694fc4a5e72bded /lib/Target/PowerPC/PPCFrameLowering.cpp | |
parent | 1c881d9d35a7880d0c102119b29d20ceb2ed1975 (diff) | |
download | llvm-aad2a72c285a48e34d89ba69d24eb624f2b09b0e.tar.gz llvm-aad2a72c285a48e34d89ba69d24eb624f2b09b0e.tar.bz2 llvm-aad2a72c285a48e34d89ba69d24eb624f2b09b0e.tar.xz |
PPC: Support dynamic allocas with large alignment
Support for dynamic stack alignments in the PPC backend has been unfinished, in
part because it depends on dynamic stack realignment (which I only just
recently implemented fully). Now we can also support dynamic allocas with
higher than the default target stack alignment (16 bytes).
In order to round-up the requested size to the maximum requested alignment, we
need an additional register to hold the rounded-up size. We're already using one
scavenged register to hold the previous stack-pointer value (which needs to be
stored with the signal-safe stdux update), and so when we have dynamic allocas
and a large alignment, we allocate two emergency spill slots for the scavenger.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186562 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/PowerPC/PPCFrameLowering.cpp')
-rw-r--r-- | lib/Target/PowerPC/PPCFrameLowering.cpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/lib/Target/PowerPC/PPCFrameLowering.cpp b/lib/Target/PowerPC/PPCFrameLowering.cpp index d846365112..24d3a0b951 100644 --- a/lib/Target/PowerPC/PPCFrameLowering.cpp +++ b/lib/Target/PowerPC/PPCFrameLowering.cpp @@ -1237,8 +1237,12 @@ PPCFrameLowering::addScavengingSpillSlot(MachineFunction &MF, RC->getAlignment(), false)); + // Might we have over-aligned allocas? + bool HasAlVars = MFI->hasVarSizedObjects() && + MFI->getMaxAlignment() > getStackAlignment(); + // These kinds of spills might need two registers. - if (spillsCR(MF) || spillsVRSAVE(MF)) + if (spillsCR(MF) || spillsVRSAVE(MF) || HasAlVars) RS->addScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(), RC->getAlignment(), false)); |