From 21554d9b302571c7d2a6e0dbd17888b1b00bb038 Mon Sep 17 00:00:00 2001 From: Matthias Braun Date: Wed, 10 Dec 2014 01:13:11 +0000 Subject: [PATCH] MachineVerifier: Allow LiveInterval segments to end at a partial write. In the subregister liveness tracking case we do not create implicit reads on partial register writes anymore, still we need to produce a new SSA value for partial writes so the live segment has to end. llvm-svn: 223895 --- llvm/lib/CodeGen/MachineVerifier.cpp | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp index 0586561..5cdcc66 100644 --- a/llvm/lib/CodeGen/MachineVerifier.cpp +++ b/llvm/lib/CodeGen/MachineVerifier.cpp @@ -1548,19 +1548,27 @@ void MachineVerifier::verifyLiveRangeSegment(const LiveRange &LR, // A live segment can end with either a redefinition, a kill flag on a // use, or a dead flag on a def. bool hasRead = false; + bool hasSubRegDef = false; for (ConstMIBundleOperands MOI(MI); MOI.isValid(); ++MOI) { if (!MOI->isReg() || MOI->getReg() != Reg) continue; if (LaneMask != 0 && (LaneMask & TRI->getSubRegIndexLaneMask(MOI->getSubReg())) == 0) continue; + if (MOI->isDef() && MOI->getSubReg() != 0) + hasSubRegDef = true; if (MOI->readsReg()) hasRead = true; } if (!S.end.isDead()) { if (!hasRead) { - report("Instruction ending live segment doesn't read the register", MI); - *OS << S << " in " << LR << '\n'; + // When tracking subregister liveness, the main range must start new + // values on partial register writes, even if there is no read. + if (!MRI->tracksSubRegLiveness() || LaneMask != 0 || !hasSubRegDef) { + report("Instruction ending live segment doesn't read the register", + MI); + *OS << S << " in " << LR << '\n'; + } } } } -- 2.7.4