diff options
| author | Hal Finkel <hfinkel@anl.gov> | 2012-05-19 21:52:55 +0000 |
|---|---|---|
| committer | Hal Finkel <hfinkel@anl.gov> | 2012-05-19 21:52:55 +0000 |
| commit | b8f2f29467b86a11e777e2ce071caf15ae6fcf75 (patch) | |
| tree | c5b84a1893a80380d7a370728adff839a4f13745 /lib/Target/PowerPC/PPCFrameLowering.cpp | |
| parent | ec096b492549d625e4be608fcaea265b96dabc03 (diff) | |
Add a FIXME about access to negative stack-pointer offsets on PPC32.
The current code will generate a prologue which starts with something like:
mflr 0
stw 31, -4(1)
stw 0, 4(1)
stwu 1, -16(1)
But under the PPC32 SVR4 ABI, access to negative offsets from R1 is not allowed.
This was pointed out by Peter Bergner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157133 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/PowerPC/PPCFrameLowering.cpp')
| -rw-r--r-- | lib/Target/PowerPC/PPCFrameLowering.cpp | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/lib/Target/PowerPC/PPCFrameLowering.cpp b/lib/Target/PowerPC/PPCFrameLowering.cpp index 5950290ca2..be172c2435 100644 --- a/lib/Target/PowerPC/PPCFrameLowering.cpp +++ b/lib/Target/PowerPC/PPCFrameLowering.cpp @@ -330,6 +330,8 @@ void PPCFrameLowering::emitPrologue(MachineFunction &MF) const { BuildMI(MBB, MBBI, dl, TII.get(PPC::MFLR), PPC::R0); if (HasFP) + // FIXME: On PPC32 SVR4, FPOffset is negative and access to negative + // offsets of R1 is not allowed. BuildMI(MBB, MBBI, dl, TII.get(PPC::STW)) .addReg(PPC::R31) .addImm(FPOffset) |