From 7618b2b23d5a0a82d3eff974d2e32629d9679b85 Mon Sep 17 00:00:00 2001 From: Matthias Braun Date: Sat, 17 Jan 2015 00:33:13 +0000 Subject: [PATCH] RegisterCoalescer: Cleanup and improved comment for a subtle detail. llvm-svn: 226353 --- llvm/lib/CodeGen/RegisterCoalescer.cpp | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/llvm/lib/CodeGen/RegisterCoalescer.cpp b/llvm/lib/CodeGen/RegisterCoalescer.cpp index c9651fc..5eb1721 100644 --- a/llvm/lib/CodeGen/RegisterCoalescer.cpp +++ b/llvm/lib/CodeGen/RegisterCoalescer.cpp @@ -2345,19 +2345,21 @@ void JoinVals::eraseInstrs(SmallPtrSetImpl &ErasedInstrs, // Get the def location before markUnused() below invalidates it. SlotIndex Def = LR.getValNumInfo(i)->def; switch (Vals[i].Resolution) { - case CR_Keep: + case CR_Keep: { // If an IMPLICIT_DEF value is pruned, it doesn't serve a purpose any // longer. The IMPLICIT_DEF instructions are only inserted by // PHIElimination to guarantee that all PHI predecessors have a value. if (!Vals[i].ErasableImplicitDef || !Vals[i].Pruned) break; - // Remove value number i from LR. Note that this VNInfo is still present - // in NewVNInfo, so it will appear as an unused value number in the final - // joined interval. - LR.getValNumInfo(i)->markUnused(); - LR.removeValNo(LR.getValNumInfo(i)); + // Remove value number i from LR. + VNInfo *VNI = LR.getValNumInfo(i); + LR.removeValNo(VNI); + // Note that this VNInfo is reused and still referenced in NewVNInfo, + // make it appear like an unused value number. + VNI->markUnused(); DEBUG(dbgs() << "\t\tremoved " << i << '@' << Def << ": " << LR << '\n'); // FALL THROUGH. + } case CR_Erase: { MachineInstr *MI = Indexes->getInstructionFromIndex(Def); -- 2.7.4