From 631ee4b89f494a3056c62f84e434e1ecf266bb8a Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Tue, 4 Jan 2011 21:10:11 +0000 Subject: Use the EdgeBundles analysis in X86FloatingPoint instead of recomputing CFG bundles in the pass. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122833 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86FloatingPoint.cpp | 101 +++++------------------------------- 1 file changed, 14 insertions(+), 87 deletions(-) (limited to 'lib/Target/X86/X86FloatingPoint.cpp') diff --git a/lib/Target/X86/X86FloatingPoint.cpp b/lib/Target/X86/X86FloatingPoint.cpp index 873a4d9..3aaa693 100644 --- a/lib/Target/X86/X86FloatingPoint.cpp +++ b/lib/Target/X86/X86FloatingPoint.cpp @@ -97,7 +97,7 @@ namespace { // FixStack[i] == getStackEntry(i) for all i < FixCount. unsigned char FixStack[8]; - LiveBundle(unsigned m = 0) : Mask(m), FixCount(0) {} + LiveBundle() : Mask(0), FixCount(0) {} // Have the live registers been assigned a stack order yet? bool isFixed() const { return !Mask || FixCount; } @@ -107,10 +107,8 @@ namespace { // with no live FP registers. SmallVector LiveBundles; - // Map each MBB in the current function to an (ingoing, outgoing) index into - // LiveBundles. Blocks with no FP registers live in or out map to (0, 0) - // and are not actually stored in the map. - DenseMap > BlockBundle; + // The edge bundle analysis provides indices into the LiveBundles vector. + EdgeBundles *Bundles; // Return a bitmask of FP registers in block's live-in list. unsigned calcLiveInMask(MachineBasicBlock *MBB) { @@ -287,6 +285,7 @@ bool FPS::runOnMachineFunction(MachineFunction &MF) { // Early exit. if (!FPIsUsed) return false; + Bundles = &getAnalysis(); TII = MF.getTarget().getInstrInfo(); // Prepare cross-MBB liveness. @@ -311,7 +310,6 @@ bool FPS::runOnMachineFunction(MachineFunction &MF) { if (Processed.insert(BB)) Changed |= processBasicBlock(MF, *BB); - BlockBundle.clear(); LiveBundles.clear(); return Changed; @@ -324,90 +322,16 @@ bool FPS::runOnMachineFunction(MachineFunction &MF) { /// registers may be implicitly defined, or not used by all successors. void FPS::bundleCFG(MachineFunction &MF) { assert(LiveBundles.empty() && "Stale data in LiveBundles"); - assert(BlockBundle.empty() && "Stale data in BlockBundle"); - SmallPtrSet PropDown, PropUp; + LiveBundles.resize(Bundles->getNumBundles()); - // LiveBundle[0] is the empty live-in set. - LiveBundles.resize(1); - - // First gather the actual live-in masks for all MBBs. + // Gather the actual live-in masks for all MBBs. for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) { MachineBasicBlock *MBB = I; const unsigned Mask = calcLiveInMask(MBB); if (!Mask) continue; - // Ingoing bundle index. - unsigned &Idx = BlockBundle[MBB].first; - // Already assigned an ingoing bundle? - if (Idx) - continue; - // Allocate a new LiveBundle struct for this block's live-ins. - const unsigned BundleIdx = Idx = LiveBundles.size(); - DEBUG(dbgs() << "Creating LB#" << BundleIdx << ": in:BB#" - << MBB->getNumber()); - LiveBundles.push_back(Mask); - LiveBundle &Bundle = LiveBundles.back(); - - // Make sure all predecessors have the same live-out set. - PropUp.insert(MBB); - - // Keep pushing liveness up and down the CFG until convergence. - // Only critical edges cause iteration here, but when they do, multiple - // blocks can be assigned to the same LiveBundle index. - do { - // Assign BundleIdx as liveout from predecessors in PropUp. - for (SmallPtrSet::iterator I = PropUp.begin(), - E = PropUp.end(); I != E; ++I) { - MachineBasicBlock *MBB = *I; - for (MachineBasicBlock::const_pred_iterator LinkI = MBB->pred_begin(), - LinkE = MBB->pred_end(); LinkI != LinkE; ++LinkI) { - MachineBasicBlock *PredMBB = *LinkI; - // PredMBB's liveout bundle should be set to LIIdx. - unsigned &Idx = BlockBundle[PredMBB].second; - if (Idx) { - assert(Idx == BundleIdx && "Inconsistent CFG"); - continue; - } - Idx = BundleIdx; - DEBUG(dbgs() << " out:BB#" << PredMBB->getNumber()); - // Propagate to siblings. - if (PredMBB->succ_size() > 1) - PropDown.insert(PredMBB); - } - } - PropUp.clear(); - - // Assign BundleIdx as livein to successors in PropDown. - for (SmallPtrSet::iterator I = PropDown.begin(), - E = PropDown.end(); I != E; ++I) { - MachineBasicBlock *MBB = *I; - for (MachineBasicBlock::const_succ_iterator LinkI = MBB->succ_begin(), - LinkE = MBB->succ_end(); LinkI != LinkE; ++LinkI) { - MachineBasicBlock *SuccMBB = *LinkI; - // LinkMBB's livein bundle should be set to BundleIdx. - unsigned &Idx = BlockBundle[SuccMBB].first; - if (Idx) { - assert(Idx == BundleIdx && "Inconsistent CFG"); - continue; - } - Idx = BundleIdx; - DEBUG(dbgs() << " in:BB#" << SuccMBB->getNumber()); - // Propagate to siblings. - if (SuccMBB->pred_size() > 1) - PropUp.insert(SuccMBB); - // Also accumulate the bundle liveness mask from the liveins here. - Bundle.Mask |= calcLiveInMask(SuccMBB); - } - } - PropDown.clear(); - } while (!PropUp.empty()); - DEBUG({ - dbgs() << " live:"; - for (unsigned i = 0; i < 8; ++i) - if (Bundle.Mask & (1<getBundle(MBB->getNumber(), false)].Mask |= Mask; } } @@ -495,13 +419,15 @@ bool FPS::processBasicBlock(MachineFunction &MF, MachineBasicBlock &BB) { return Changed; } -/// setupBlockStack - Use the BlockBundle map to set up our model of the stack +/// setupBlockStack - Use the live bundles to set up our model of the stack /// to match predecessors' live out stack. void FPS::setupBlockStack() { DEBUG(dbgs() << "\nSetting up live-ins for BB#" << MBB->getNumber() << " derived from " << MBB->getName() << ".\n"); StackTop = 0; - const LiveBundle &Bundle = LiveBundles[BlockBundle.lookup(MBB).first]; + // Get the live-in bundle for MBB. + const LiveBundle &Bundle = + LiveBundles[Bundles->getBundle(MBB->getNumber(), false)]; if (!Bundle.Mask) { DEBUG(dbgs() << "Block has no FP live-ins.\n"); @@ -538,7 +464,8 @@ void FPS::finishBlockStack() { DEBUG(dbgs() << "Setting up live-outs for BB#" << MBB->getNumber() << " derived from " << MBB->getName() << ".\n"); - unsigned BundleIdx = BlockBundle.lookup(MBB).second; + // Get MBB's live-out bundle. + unsigned BundleIdx = Bundles->getBundle(MBB->getNumber(), true); LiveBundle &Bundle = LiveBundles[BundleIdx]; // We may need to kill and define some registers to match successors. -- cgit v1.1