From 7d892d6e6d451e9a0d0f9db839a943a256126c05 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 1 Mar 2010 07:43:08 +0000 Subject: [PATCH] some trivial microoptimizations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97441 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 14 ++++++++------ lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 13 ++++++++++--- 2 files changed, 18 insertions(+), 9 deletions(-) diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index f008fad3467..a3f5f39f6f0 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -4736,12 +4736,14 @@ SDNode *SelectionDAG::MorphNodeTo(SDNode *N, unsigned Opc, // Delete any nodes that are still dead after adding the uses for the // new operands. - SmallVector DeadNodes; - for (SmallPtrSet::iterator I = DeadNodeSet.begin(), - E = DeadNodeSet.end(); I != E; ++I) - if ((*I)->use_empty()) - DeadNodes.push_back(*I); - RemoveDeadNodes(DeadNodes); + if (!DeadNodeSet.empty()) { + SmallVector DeadNodes; + for (SmallPtrSet::iterator I = DeadNodeSet.begin(), + E = DeadNodeSet.end(); I != E; ++I) + if ((*I)->use_empty()) + DeadNodes.push_back(*I); + RemoveDeadNodes(DeadNodes); + } if (IP) CSEMap.InsertNode(N, IP); // Memoize the new node. diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index f1e6b960ee0..03cbe22c0c5 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -1760,7 +1760,7 @@ SelectCodeCommon(SDNode *NodeToMatch, const unsigned char *MatcherTable, case OPC_SwitchOpcode: { unsigned CurNodeOpcode = N.getOpcode(); - unsigned SwitchStart = MatcherIndex-1; + unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart; unsigned CaseSize; while (1) { @@ -2060,8 +2060,15 @@ SelectCodeCommon(SDNode *NodeToMatch, const unsigned char *MatcherTable, if (EmitNodeInfo & OPFL_FlagOutput) VTs.push_back(MVT::Flag); - // FIXME: Use faster version for the common 'one VT' case? - SDVTList VTList = CurDAG->getVTList(VTs.data(), VTs.size()); + // This is hot code, so optimize the two most common cases of 1 and 2 + // results. + SDVTList VTList; + if (VTs.size() == 1) + VTList = CurDAG->getVTList(VTs[0]); + else if (VTs.size() == 2) + VTList = CurDAG->getVTList(VTs[0], VTs[1]); + else + VTList = CurDAG->getVTList(VTs.data(), VTs.size()); // Get the operand list. unsigned NumOps = MatcherTable[MatcherIndex++]; -- 2.34.1