From 64bdde2093f461f10c095d08d53dc57c6612ce69 Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Fri, 11 Dec 2009 03:14:18 +0000 Subject: Address comments on last patch: - Loosen the restrictions when checking of it branches to a landing pad. - Make the loop more efficient by checking the '.insert' return value. - Do cheaper checks first. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91101 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/MachineBasicBlock.cpp | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) (limited to 'lib/CodeGen/MachineBasicBlock.cpp') diff --git a/lib/CodeGen/MachineBasicBlock.cpp b/lib/CodeGen/MachineBasicBlock.cpp index 684af34494..7ce723e019 100644 --- a/lib/CodeGen/MachineBasicBlock.cpp +++ b/lib/CodeGen/MachineBasicBlock.cpp @@ -449,24 +449,19 @@ void MachineBasicBlock::ReplaceUsesOfBlockWith(MachineBasicBlock *Old, addSuccessor(New); } -/// BranchesToLandingPad - The basic block branches only to a landing pad or to -/// another basic block which branches only to a landing pad. No other -/// instructions are present other than the unconditional branch. +/// BranchesToLandingPad - The basic block is a landing pad or branches only to +/// a landing pad. No other instructions are present other than the +/// unconditional branch. bool MachineBasicBlock::BranchesToLandingPad(const MachineBasicBlock *MBB) const { SmallSet Visited; const MachineBasicBlock *CurMBB = MBB; - while (!Visited.count(CurMBB) && !CurMBB->isLandingPad()) { - if (CurMBB->size() != 1 || CurMBB->succ_empty() || CurMBB->succ_size() != 1) + while (!CurMBB->isLandingPad()) { + if (CurMBB->succ_size() != 1) break; - const TargetInstrInfo *TII = - CurMBB->getParent()->getTarget().getInstrInfo(); - if (!TII->isUnpredicatedTerminator(CurMBB->begin())) - break; - - Visited.insert(CurMBB); + if (!Visited.insert(CurMBB)) break; CurMBB = *CurMBB->succ_begin(); } @@ -516,8 +511,8 @@ bool MachineBasicBlock::CorrectExtraCFGEdges(MachineBasicBlock *DestA, } else if (MBB == DestB) { DestB = 0; ++SI; - } else if (BranchesToLandingPad(MBB) && - MBB != OrigDestA && MBB != OrigDestB) { + } else if (MBB != OrigDestA && MBB != OrigDestB && + BranchesToLandingPad(MBB)) { ++SI; } else { // Otherwise, this is a superfluous edge, remove it. -- cgit v1.2.3-18-g5258