diff options
| -rw-r--r-- | lib/Target/PowerPC/PPC.h | 3 | ||||
| -rw-r--r-- | lib/Target/PowerPC/PPCCTRLoops.cpp | 155 | ||||
| -rw-r--r-- | lib/Target/PowerPC/PPCTargetMachine.cpp | 6 |
3 files changed, 164 insertions, 0 deletions
diff --git a/lib/Target/PowerPC/PPC.h b/lib/Target/PowerPC/PPC.h index 28b654cf08..2e7961014b 100644 --- a/lib/Target/PowerPC/PPC.h +++ b/lib/Target/PowerPC/PPC.h @@ -31,6 +31,9 @@ namespace llvm { class MCInst; FunctionPass *createPPCCTRLoops(PPCTargetMachine &TM); +#ifndef NDEBUG + FunctionPass *createPPCCTRLoopsVerify(); +#endif FunctionPass *createPPCEarlyReturnPass(); FunctionPass *createPPCBranchSelectionPass(); FunctionPass *createPPCISelDag(PPCTargetMachine &TM); diff --git a/lib/Target/PowerPC/PPCCTRLoops.cpp b/lib/Target/PowerPC/PPCCTRLoops.cpp index e8760dedea..d36fec0a0a 100644 --- a/lib/Target/PowerPC/PPCCTRLoops.cpp +++ b/lib/Target/PowerPC/PPCCTRLoops.cpp @@ -48,6 +48,13 @@ #include "PPCTargetMachine.h" #include "PPC.h" +#ifndef NDEBUG +#include "llvm/CodeGen/MachineDominators.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineFunctionPass.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" +#endif + #include <algorithm> #include <vector> @@ -61,6 +68,9 @@ STATISTIC(NumCTRLoops, "Number of loops converted to CTR loops"); namespace llvm { void initializePPCCTRLoopsPass(PassRegistry&); +#ifndef NDEBUG + void initializePPCCTRLoopsVerifyPass(PassRegistry&); +#endif } namespace { @@ -112,6 +122,29 @@ namespace { #ifndef NDEBUG int PPCCTRLoops::Counter = 0; #endif + +#ifndef NDEBUG + struct PPCCTRLoopsVerify : public MachineFunctionPass { + public: + static char ID; + + PPCCTRLoopsVerify() : MachineFunctionPass(ID) { + initializePPCCTRLoopsVerifyPass(*PassRegistry::getPassRegistry()); + } + + virtual void getAnalysisUsage(AnalysisUsage &AU) const { + AU.addRequired<MachineDominatorTree>(); + MachineFunctionPass::getAnalysisUsage(AU); + } + + virtual bool runOnMachineFunction(MachineFunction &MF); + + private: + MachineDominatorTree *MDT; + }; + + char PPCCTRLoopsVerify::ID = 0; +#endif // NDEBUG } // end anonymous namespace INITIALIZE_PASS_BEGIN(PPCCTRLoops, "ppc-ctr-loops", "PowerPC CTR Loops", @@ -126,6 +159,18 @@ FunctionPass *llvm::createPPCCTRLoops(PPCTargetMachine &TM) { return new PPCCTRLoops(TM); } +#ifndef NDEBUG +INITIALIZE_PASS_BEGIN(PPCCTRLoopsVerify, "ppc-ctr-loops-verify", + "PowerPC CTR Loops Verify", false, false) +INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) +INITIALIZE_PASS_END(PPCCTRLoopsVerify, "ppc-ctr-loops-verify", + "PowerPC CTR Loops Verify", false, false) + +FunctionPass *llvm::createPPCCTRLoopsVerify() { + return new PPCCTRLoopsVerify(); +} +#endif // NDEBUG + bool PPCCTRLoops::runOnFunction(Function &F) { LI = &getAnalysis<LoopInfo>(); SE = &getAnalysis<ScalarEvolution>(); @@ -545,3 +590,113 @@ void PPCCTRLoops::PlaceSplitBlockCarefully(BasicBlock *NewBB, NewBB->moveAfter(FoundBB); } +#ifndef NDEBUG +static bool clobbersCTR(const MachineInstr *MI) { + for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { + const MachineOperand &MO = MI->getOperand(i); + if (MO.isReg()) { + if (MO.isDef() && (MO.getReg() == PPC::CTR || MO.getReg() == PPC::CTR8)) + return true; + } else if (MO.isRegMask()) { + if (MO.clobbersPhysReg(PPC::CTR) || MO.clobbersPhysReg(PPC::CTR8)) + return true; + } + } + + return false; +} + +static bool verifyCTRBranch(MachineBasicBlock *MBB, + MachineBasicBlock::iterator I) { + MachineBasicBlock::iterator BI = I; + SmallSet<MachineBasicBlock *, 16> Visited; + SmallVector<MachineBasicBlock *, 8> Preds; + bool CheckPreds; + + if (I == MBB->begin()) { + Visited.insert(MBB); + goto queue_preds; + } else + --I; + +check_block: + Visited.insert(MBB); + if (I == MBB->end()) + goto queue_preds; + + CheckPreds = true; + for (MachineBasicBlock::iterator IE = MBB->begin();; --I) { + unsigned Opc = I->getOpcode(); + if (Opc == PPC::MTCTRse || Opc == PPC::MTCTR8se) { + CheckPreds = false; + break; + } + + if (I != BI && clobbersCTR(I)) { + DEBUG(dbgs() << "BB#" << MBB->getNumber() << " (" << + MBB->getFullName() << ") instruction " << *I << + " clobbers CTR, invalidating " << "BB#" << + BI->getParent()->getNumber() << " (" << + BI->getParent()->getFullName() << ") instruction " << + *BI << "\n"); + return false; + } + + if (I == IE) + break; + } + + if (!CheckPreds && Preds.empty()) + return true; + + if (CheckPreds) { +queue_preds: + if (MachineFunction::iterator(MBB) == MBB->getParent()->begin()) { + DEBUG(dbgs() << "Unable to find a MTCTR instruction for BB#" << + BI->getParent()->getNumber() << " (" << + BI->getParent()->getFullName() << ") instruction " << + *BI << "\n"); + return false; + } + + for (MachineBasicBlock::pred_iterator PI = MBB->pred_begin(), + PIE = MBB->pred_end(); PI != PIE; ++PI) + Preds.push_back(*PI); + } + + do { + MBB = Preds.pop_back_val(); + if (!Visited.count(MBB)) { + I = MBB->getLastNonDebugInstr(); + goto check_block; + } + } while (!Preds.empty()); + + return true; +} + +bool PPCCTRLoopsVerify::runOnMachineFunction(MachineFunction &MF) { + MDT = &getAnalysis<MachineDominatorTree>(); + + // Verify that all bdnz/bdz instructions are dominated by a loop mtctr before + // any other instructions that might clobber the ctr register. + for (MachineFunction::iterator I = MF.begin(), IE = MF.end(); + I != IE; ++I) { + MachineBasicBlock *MBB = I; + if (!MDT->isReachableFromEntry(MBB)) + continue; + + for (MachineBasicBlock::iterator MII = MBB->getFirstTerminator(), + MIIE = MBB->end(); MII != MIIE; ++MII) { + unsigned Opc = MII->getOpcode(); + if (Opc == PPC::BDNZ8 || Opc == PPC::BDNZ || + Opc == PPC::BDZ8 || Opc == PPC::BDZ) + if (!verifyCTRBranch(MBB, MII)) + llvm_unreachable("Invalid PPC CTR loop!"); + } + } + + return false; +} +#endif // NDEBUG + diff --git a/lib/Target/PowerPC/PPCTargetMachine.cpp b/lib/Target/PowerPC/PPCTargetMachine.cpp index ca012670f3..da03b4cef7 100644 --- a/lib/Target/PowerPC/PPCTargetMachine.cpp +++ b/lib/Target/PowerPC/PPCTargetMachine.cpp @@ -122,6 +122,12 @@ bool PPCPassConfig::addILPOpts() { bool PPCPassConfig::addInstSelector() { // Install an instruction selector. addPass(createPPCISelDag(getPPCTargetMachine())); + +#ifndef NDEBUG + if (!DisableCTRLoops && getOptLevel() != CodeGenOpt::None) + addPass(createPPCCTRLoopsVerify()); +#endif + return false; } |