From de819d779135b59d25fbed6c3128cb80f5dddc32 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Sun, 16 Dec 2007 04:07:23 +0000 Subject: A few more comments. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45069 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/StrongPHIElimination.cpp | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp index 9b1c163..ee62a6b 100644 --- a/lib/CodeGen/StrongPHIElimination.cpp +++ b/lib/CodeGen/StrongPHIElimination.cpp @@ -311,6 +311,10 @@ void StrongPHIElimination::processBlock(MachineBasicBlock* MBB) { } } +/// processPHIUnion - Take a set of candidate registers to be coallesced when +/// decomposing the PHI instruction. Use the DominanceForest to remove the ones +/// that are known to interfere, and flag others that need to be checked for +/// local interferences. void StrongPHIElimination::processPHIUnion(MachineInstr* Inst, std::set& PHIUnion, std::vector& DF, @@ -322,6 +326,7 @@ void StrongPHIElimination::processPHIUnion(MachineInstr* Inst, LiveVariables& LV = getAnalysis(); unsigned DestReg = Inst->getOperand(0).getReg(); + // DF walk on the DomForest while (!worklist.empty()) { DomForestNode* DFNode = worklist.back(); @@ -350,7 +355,7 @@ void StrongPHIElimination::processPHIUnion(MachineInstr* Inst, // Add (p, c) to possible local interferences locals.push_back(std::make_pair(DFNode->getReg(), child->getReg())); } - + if (!visited.count(child)) { worklist.push_back(child); inserted = true; -- cgit v1.1