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| author | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2012-10-29 17:51:52 +0000 |
|---|---|---|
| committer | Jakob Stoklund Olesen <stoklund@2pi.dk> | 2012-10-29 17:51:52 +0000 |
| commit | 573303e62a913ec881fde3434d7babed0bd4da33 (patch) | |
| tree | c2a6427d3525e7ddec03f1b52477d05700071aeb /lib/CodeGen/RegisterCoalescer.cpp | |
| parent | 78dab643e0d49cc76ca20409d733c23bc17171dd (diff) | |
| download | llvm-573303e62a913ec881fde3434d7babed0bd4da33.tar.gz llvm-573303e62a913ec881fde3434d7babed0bd4da33.tar.bz2 llvm-573303e62a913ec881fde3434d7babed0bd4da33.tar.xz | |
Completely disallow partial copies in adjustCopiesBackFrom().
Partial copies can show up even when CoalescerPair.isPartial() returns
false. For example:
%vreg24:dsub_0<def> = COPY %vreg31:dsub_0; QPR:%vreg24,%vreg31
Such a partial-partial copy is not good enough for the transformation
adjustCopiesBackFrom() needs to do.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166944 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/RegisterCoalescer.cpp')
| -rw-r--r-- | lib/CodeGen/RegisterCoalescer.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/lib/CodeGen/RegisterCoalescer.cpp b/lib/CodeGen/RegisterCoalescer.cpp index 7592074478..ac0ed5f611 100644 --- a/lib/CodeGen/RegisterCoalescer.cpp +++ b/lib/CodeGen/RegisterCoalescer.cpp @@ -430,7 +430,8 @@ bool RegisterCoalescer::adjustCopiesBackFrom(const CoalescerPair &CP, // If AValNo is defined as a copy from IntB, we can potentially process this. // Get the instruction that defines this value number. MachineInstr *ACopyMI = LIS->getInstructionFromIndex(AValNo->def); - if (!CP.isCoalescable(ACopyMI)) + // Don't allow any partial copies, even if isCoalescable() allows them. + if (!CP.isCoalescable(ACopyMI) || !ACopyMI->isFullCopy()) return false; // Get the LiveRange in IntB that this value number starts with. |