From a279a896ecd1601060adcc6563488f27b12319ef Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Fri, 25 Jul 2008 23:38:08 +0000 Subject: [PATCH] Fix the issues originally addressed in r54070. After thinking about it some more, I realized that the right thing to do is to have StrongPHIElimination use its knowledge of the PHIs before they're erased to update the intervals appropriate. This is both simpler and more accurate than the alternative, which was having LIA figure it out when it renumbered things, plus it's just the right thing to do! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54077 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/StrongPHIElimination.cpp | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp index 7f98463e48c..399e6154184 100644 --- a/lib/CodeGen/StrongPHIElimination.cpp +++ b/lib/CodeGen/StrongPHIElimination.cpp @@ -741,7 +741,7 @@ void StrongPHIElimination::ScheduleCopies(MachineBasicBlock* MBB, std::set RegHandled; for (SmallVector, 4>::iterator I = InsertedPHIDests.begin(), E = InsertedPHIDests.end(); I != E; ++I) - if (!RegHandled.insert(I->first).second) + if (RegHandled.insert(I->first).second) LI.addLiveRangeToEndOfBlock(I->first, I->second); } @@ -846,6 +846,19 @@ bool StrongPHIElimination::runOnMachineFunction(MachineFunction &Fn) { I != E; ) { MachineInstr* PInstr = *(I++); + // Trim live intervals of input registers. They are no longer live into + // this block. + for (unsigned i = 1; i < PInstr->getNumOperands(); i += 2) { + unsigned reg = PInstr->getOperand(i).getReg(); + MachineBasicBlock* MBB = PInstr->getOperand(i+1).getMBB(); + LiveInterval& InputI = LI.getInterval(reg); + if (MBB != PInstr->getParent() && + InputI.liveAt(LI.getMBBStartIdx(PInstr->getParent()))) + InputI.removeRange(LI.getMBBStartIdx(PInstr->getParent()), + LI.getInstructionIndex(PInstr), + true); + } + // If this is a dead PHI node, then remove it from LiveIntervals. unsigned DestReg = PInstr->getOperand(0).getReg(); LiveInterval& PI = LI.getInterval(DestReg); @@ -860,7 +873,11 @@ bool StrongPHIElimination::runOnMachineFunction(MachineFunction &Fn) { // If the PHI is not dead, then the valno defined by the PHI // now has an unknown def. unsigned idx = LI.getDefIndex(LI.getInstructionIndex(PInstr)); - PI.getLiveRangeContaining(idx)->valno->def = ~0U; + const LiveRange* PLR = PI.getLiveRangeContaining(idx); + PLR->valno->def = ~0U; + LiveRange R (LI.getMBBStartIdx(PInstr->getParent()), + PLR->start, PLR->valno); + PI.addRange(R); } LI.RemoveMachineInstrFromMaps(PInstr);