From 6d309059a7d6257ddeb3b07e6c4b8b71cce2f707 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Fri, 29 Oct 2010 17:37:29 +0000 Subject: Teach ConnectedVNInfoEqClasses::Classify to deal with unused values. We don't want unused values forming their own equivalence classes, so we lump them all together in one class, and then merge them with the class of the last used value. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117670 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/LiveInterval.cpp | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) (limited to 'lib/CodeGen/LiveInterval.cpp') diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp index 27a572c0ea..3c18017f3f 100644 --- a/lib/CodeGen/LiveInterval.cpp +++ b/lib/CodeGen/LiveInterval.cpp @@ -740,11 +740,20 @@ unsigned ConnectedVNInfoEqClasses::Classify(const LiveInterval *LI) { for (unsigned i = 0, e = LI->getNumValNums(); i != e; ++i) eqClass_.push_back(i); + const VNInfo *used = 0, *unused = 0; + // Determine connections. for (LiveInterval::const_vni_iterator I = LI->vni_begin(), E = LI->vni_end(); I != E; ++I) { const VNInfo *VNI = *I; - assert(!VNI->isUnused() && "Cannot handle unused values"); + // Group all unused values into one class. + if (VNI->isUnused()) { + if (unused) + Connect(unused->id, VNI->id); + unused = VNI; + continue; + } + used = VNI; if (VNI->isPHIDef()) { const MachineBasicBlock *MBB = lis_.getMBBFromIndex(VNI->def); assert(MBB && "Phi-def has no defining MBB"); @@ -762,6 +771,11 @@ unsigned ConnectedVNInfoEqClasses::Classify(const LiveInterval *LI) { Connect(VNI->id, UVNI->id); } } + + // Lump all the unused values in with the last used value. + if (used && unused) + Connect(used->id, unused->id); + return Renumber(); } -- cgit v1.2.3