From a97ff8a027259b1b9e4dbdb5b6f01cc2195a6948 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Thu, 3 Mar 2011 05:18:19 +0000 Subject: [PATCH] Avoid comparing invalid slot indexes, and assert that it doesn't happen. The SlotIndex created by the default construction does not represent a position in the function, and it doesn't make sense to compare it to other indexes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126924 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/CodeGen/SlotIndexes.h | 3 ++- lib/CodeGen/RegAllocLinearScan.cpp | 4 ++-- lib/CodeGen/SimpleRegisterCoalescing.cpp | 4 +--- 3 files changed, 5 insertions(+), 6 deletions(-) diff --git a/include/llvm/CodeGen/SlotIndexes.h b/include/llvm/CodeGen/SlotIndexes.h index 8d3b1c09335..153e520a477 100644 --- a/include/llvm/CodeGen/SlotIndexes.h +++ b/include/llvm/CodeGen/SlotIndexes.h @@ -135,6 +135,7 @@ namespace llvm { } IndexListEntry& entry() const { + assert(isValid() && "Attempt to compare reserved index."); return *lie.getPointer(); } @@ -530,7 +531,7 @@ namespace llvm { /// Returns the instruction for the given index, or null if the given /// index has no instruction associated with it. MachineInstr* getInstructionFromIndex(SlotIndex index) const { - return index.entry().getInstr(); + return index.isValid() ? index.entry().getInstr() : 0; } /// Returns the next non-null index. diff --git a/lib/CodeGen/RegAllocLinearScan.cpp b/lib/CodeGen/RegAllocLinearScan.cpp index b959878bcdb..a24fc80cf5e 100644 --- a/lib/CodeGen/RegAllocLinearScan.cpp +++ b/lib/CodeGen/RegAllocLinearScan.cpp @@ -458,7 +458,7 @@ unsigned RALinScan::attemptTrivialCoalescing(LiveInterval &cur, unsigned Reg) { const LiveRange &range = cur.ranges.front(); VNInfo *vni = range.valno; - if (vni->isUnused()) + if (vni->isUnused() || !vni->def.isValid()) return Reg; unsigned CandReg; @@ -993,7 +993,7 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) { // one, e.g. X86::mov32to32_. These move instructions are not coalescable. if (!vrm_->getRegAllocPref(cur->reg) && cur->hasAtLeastOneValue()) { VNInfo *vni = cur->begin()->valno; - if (!vni->isUnused()) { + if (!vni->isUnused() && vni->def.isValid()) { MachineInstr *CopyMI = li_->getInstructionFromIndex(vni->def); if (CopyMI && CopyMI->isCopy()) { unsigned DstSubReg = CopyMI->getOperand(0).getSubReg(); diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index 2843c1a5b6d..74898c210a4 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -1568,9 +1568,7 @@ SimpleRegisterCoalescing::lastRegisterUse(SlotIndex Start, if (UseMI->isIdentityCopy()) continue; SlotIndex Idx = li_->getInstructionIndex(UseMI); - // FIXME: Should this be Idx != UseIdx? SlotIndex() will return something - // that compares higher than any other interval. - if (Idx >= Start && Idx < End && Idx >= UseIdx) { + if (Idx >= Start && Idx < End && (!UseIdx.isValid() || Idx >= UseIdx)) { LastUse = &Use; UseIdx = Idx.getUseIndex(); } -- 2.34.1