Make LiveVariables an instance variable of PHIElimination.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174828 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Cameron Zwarich 2013-02-10 06:42:30 +00:00
parent e9288fbe4d
commit fe0fd35d53

View File

@ -42,6 +42,7 @@ DisableEdgeSplitting("disable-phi-elim-edge-splitting", cl::init(false),
namespace {
class PHIElimination : public MachineFunctionPass {
MachineRegisterInfo *MRI; // Machine register information
LiveVariables *LV;
public:
static char ID; // Pass identification, replacement for typeid
@ -70,7 +71,7 @@ namespace {
/// Split critical edges where necessary for good coalescer performance.
bool SplitPHIEdges(MachineFunction &MF, MachineBasicBlock &MBB,
LiveVariables &LV, MachineLoopInfo *MLI);
MachineLoopInfo *MLI);
typedef std::pair<unsigned, unsigned> BBVRegPair;
typedef DenseMap<BBVRegPair, unsigned> VRegPHIUse;
@ -110,6 +111,7 @@ void PHIElimination::getAnalysisUsage(AnalysisUsage &AU) const {
bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
MRI = &MF.getRegInfo();
LV = getAnalysisIfAvailable<LiveVariables>();
bool Changed = false;
@ -117,12 +119,10 @@ bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
MRI->leaveSSA();
// Split critical edges to help the coalescer
if (!DisableEdgeSplitting) {
if (LiveVariables *LV = getAnalysisIfAvailable<LiveVariables>()) {
MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
Changed |= SplitPHIEdges(MF, *I, *LV, MLI);
}
if (!DisableEdgeSplitting && LV) {
MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
Changed |= SplitPHIEdges(MF, *I, MLI);
}
// Populate VRegPHIUseCount
@ -244,7 +244,6 @@ void PHIElimination::LowerAtomicPHINode(
}
// Update live variable information if there is any.
LiveVariables *LV = getAnalysisIfAvailable<LiveVariables>();
if (LV) {
MachineInstr *PHICopy = prior(AfterPHIsIt);
@ -418,7 +417,6 @@ void PHIElimination::analyzePHINodes(const MachineFunction& MF) {
bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
MachineBasicBlock &MBB,
LiveVariables &LV,
MachineLoopInfo *MLI) {
if (MBB.empty() || !MBB.front().isPHI() || MBB.isLandingPad())
return false; // Quick exit for basic blocks without PHIs.
@ -450,7 +448,7 @@ bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
// there is a risk it may not be coalesced away.
//
// If the copy would be a kill, there is no need to split the edge.
if (!LV.isLiveOut(Reg, *PreMBB))
if (!LV->isLiveOut(Reg, *PreMBB))
continue;
DEBUG(dbgs() << PrintReg(Reg) << " live-out before critical edge BB#"
@ -465,7 +463,7 @@ bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
// is likely to be left after coalescing. If we are looking at a loop
// exiting edge, split it so we won't insert code in the loop, otherwise
// don't bother.
bool ShouldSplit = !LV.isLiveIn(Reg, MBB);
bool ShouldSplit = !LV->isLiveIn(Reg, MBB);
// Check for a loop exiting edge.
if (!ShouldSplit && CurLoop != PreLoop) {