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| author | Alexey Samsonov <vonosmas@gmail.com> | 2014-08-20 21:56:43 +0000 |
|---|---|---|
| committer | Alexey Samsonov <vonosmas@gmail.com> | 2014-08-20 21:56:43 +0000 |
| commit | fffd56ecdf348630bba0e1500229f2fa8d7e8101 (patch) | |
| tree | f2f9c15153ad3a8e39d6e30ddcd64c626c961d5b /llvm/lib | |
| parent | 7e75cbaf47260f4bd22db4ac64d003e443cca672 (diff) | |
| download | bcm5719-llvm-fffd56ecdf348630bba0e1500229f2fa8d7e8101.tar.gz bcm5719-llvm-fffd56ecdf348630bba0e1500229f2fa8d7e8101.zip | |
Fix undefined behavior (left shift of negative value) in SystemZ backend.
This bug is reported by UBSan.
llvm-svn: 216131
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp | 2 | ||||
| -rw-r--r-- | llvm/lib/Target/SystemZ/SystemZISelLowering.cpp | 8 |
2 files changed, 3 insertions, 7 deletions
diff --git a/llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp b/llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp index db1a005353b..eff4ae3baf3 100644 --- a/llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp +++ b/llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp @@ -294,7 +294,7 @@ static void emitIncrement(MachineBasicBlock &MBB, else { Opcode = SystemZ::AGFI; // Make sure we maintain 8-byte stack alignment. - int64_t MinVal = -int64_t(1) << 31; + int64_t MinVal = -uint64_t(1) << 31; int64_t MaxVal = (int64_t(1) << 31) - 8; if (ThisVal < MinVal) ThisVal = MinVal; diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp index 228ca6e3d1e..3ca2dbae6e4 100644 --- a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp +++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp @@ -2800,14 +2800,10 @@ SystemZTargetLowering::emitAtomicLoadBinary(MachineInstr *MI, unsigned Tmp = MRI.createVirtualRegister(RC); BuildMI(MBB, DL, TII->get(BinOpcode), Tmp) .addReg(RotatedOldVal).addOperand(Src2); - if (BitSize < 32) + if (BitSize <= 32) // XILF with the upper BitSize bits set. BuildMI(MBB, DL, TII->get(SystemZ::XILF), RotatedNewVal) - .addReg(Tmp).addImm(uint32_t(~0 << (32 - BitSize))); - else if (BitSize == 32) - // XILF with every bit set. - BuildMI(MBB, DL, TII->get(SystemZ::XILF), RotatedNewVal) - .addReg(Tmp).addImm(~uint32_t(0)); + .addReg(Tmp).addImm(-1U << (32 - BitSize)); else { // Use LCGR and add -1 to the result, which is more compact than // an XILF, XILH pair. |
