From 27d404ccd1e86b7fffaf8037bf6b6dfb0b9d683b Mon Sep 17 00:00:00 2001 From: Nate Begeman Date: Tue, 4 Oct 2005 00:37:37 +0000 Subject: [PATCH] Add back a workaround that fixes some breakages from chris's last change. Neither of us have yet figured out why this code is necessary, but stuff breaks if its not there. Still tracking this down... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23617 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index a59325e4f2f..2250c7f431c 100644 --- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -623,9 +623,20 @@ SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) { Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain. // Do not try to legalize the target-specific arguments (#1+) Tmp2 = Node->getOperand(0); - if (Tmp1 != Tmp2) + if (Tmp1 != Tmp2) { Node->setAdjCallChain(Tmp1); - + + // If moving the operand from pointing to Tmp2 dropped its use count to 1, + // this will cause the maps used to memoize results to get confused. + // Create and add a dummy use, just to increase its use count. This will + // be removed at the end of legalize when dead nodes are removed. + if (Tmp2.Val->hasOneUse()) { + // FIXME: find out why this code is necessary + DAG.getNode(ISD::PCMARKER, MVT::Other, Tmp2, + DAG.getConstant(0, MVT::i32)); + } + } + // Note that we do not create new CALLSEQ_DOWN/UP nodes here. These // nodes are treated specially and are mutated in place. This makes the dag // legalization process more efficient and also makes libcall insertion