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| author | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2011-02-09 21:52:09 +0000 |
|---|---|---|
| committer | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2011-02-09 21:52:09 +0000 |
| commit | a372d16f92392bb4cd4184783466f0300a51a9ae (patch) | |
| tree | dd3658e0d5977013be04c7ebf84c652aa723ae24 /lib | |
| parent | e5005d0062fa4c8f5707428f7b8ad8484a002d83 (diff) | |
| download | llvm-a372d16f92392bb4cd4184783466f0300a51a9ae.tar.gz llvm-a372d16f92392bb4cd4184783466f0300a51a9ae.tar.bz2 llvm-a372d16f92392bb4cd4184783466f0300a51a9ae.tar.xz | |
Ignore <undef> uses when analyzing and rewriting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125226 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/CodeGen/SplitKit.cpp | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp index e26d909211..2f36f163f6 100644 --- a/lib/CodeGen/SplitKit.cpp +++ b/lib/CodeGen/SplitKit.cpp @@ -64,8 +64,12 @@ bool SplitAnalysis::canAnalyzeBranch(const MachineBasicBlock *MBB) { /// analyzeUses - Count instructions, basic blocks, and loops using CurLI. void SplitAnalysis::analyzeUses() { const MachineRegisterInfo &MRI = MF.getRegInfo(); - for (MachineRegisterInfo::reg_iterator I = MRI.reg_begin(CurLI->reg); - MachineInstr *MI = I.skipInstruction();) { + for (MachineRegisterInfo::reg_iterator I = MRI.reg_begin(CurLI->reg), + E = MRI.reg_end(); I != E; ++I) { + MachineOperand &MO = I.getOperand(); + if (MO.isUse() && MO.isUndef()) + continue; + MachineInstr *MI = MO.getParent(); if (MI->isDebugValue() || !UsingInstrs.insert(MI)) continue; UseSlots.push_back(LIS.getInstructionIndex(MI).getDefIndex()); @@ -918,6 +922,14 @@ void SplitEditor::rewriteAssigned() { MO.setReg(0); continue; } + + // <undef> operands don't really read the register, so just assign them to + // the complement. + if (MO.isUse() && MO.isUndef()) { + MO.setReg(Edit.get(0)->reg); + continue; + } + SlotIndex Idx = LIS.getInstructionIndex(MI); Idx = MO.isUse() ? Idx.getUseIndex() : Idx.getDefIndex(); |