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| author | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2011-03-18 03:06:04 +0000 |
|---|---|---|
| committer | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2011-03-18 03:06:04 +0000 |
| commit | 9ef931e71c06a0390d6387859843be1d6d4daad6 (patch) | |
| tree | a569cee7f983411f890b6cd40e1e4450a79ca62d /lib/CodeGen/LiveIntervalAnalysis.cpp | |
| parent | 7cec179a647bff132d7af36d91df877056880c5e (diff) | |
| download | llvm-9ef931e71c06a0390d6387859843be1d6d4daad6.tar.gz llvm-9ef931e71c06a0390d6387859843be1d6d4daad6.tar.bz2 llvm-9ef931e71c06a0390d6387859843be1d6d4daad6.tar.xz | |
Accept instructions that read undefined values.
This is not supposed to happen, but I have seen the x86 rematter getting
confused when rematerializing partial redefs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127857 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/LiveIntervalAnalysis.cpp')
| -rw-r--r-- | lib/CodeGen/LiveIntervalAnalysis.cpp | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp index c47c839748..d1de6a8539 100644 --- a/lib/CodeGen/LiveIntervalAnalysis.cpp +++ b/lib/CodeGen/LiveIntervalAnalysis.cpp @@ -761,7 +761,15 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li, continue; SlotIndex Idx = getInstructionIndex(UseMI).getUseIndex(); VNInfo *VNI = li->getVNInfoAt(Idx); - assert(VNI && "Live interval not live into reading instruction"); + if (!VNI) { + // This shouldn't happen: readsVirtualRegister returns true, but there is + // no live value. It is likely caused by a target getting <undef> flags + // wrong. + DEBUG(dbgs() << Idx << '\t' << *UseMI + << "Warning: Instr claims to read non-existent value in " + << *li << '\n'); + continue; + } if (VNI->def == Idx) { // Special case: An early-clobber tied operand reads and writes the // register one slot early. |