//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "phielim"
#include "llvm/CodeGen/Passes.h"
#include "PHIEliminationUtils.h"
#include "llvm/ADT/STLExtras.h"
#include <algorithm>
using namespace llvm;
+#define DEBUG_TYPE "phielim"
+
static cl::opt<bool>
DisableEdgeSplitting("disable-phi-elim-edge-splitting", cl::init(false),
cl::Hidden, cl::desc("Disable critical edge splitting "
initializePHIEliminationPass(*PassRegistry::getPassRegistry());
}
- virtual bool runOnMachineFunction(MachineFunction &Fn);
- virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+ bool runOnMachineFunction(MachineFunction &Fn) override;
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
private:
/// EliminatePHINodes - Eliminate phi nodes by inserting copy instructions
/// This includes registers with no defs.
static bool isImplicitlyDefined(unsigned VirtReg,
const MachineRegisterInfo *MRI) {
- for (MachineRegisterInfo::def_iterator DI = MRI->def_begin(VirtReg),
- DE = MRI->def_end(); DI != DE; ++DI)
- if (!DI->isImplicitDef())
+ for (MachineInstr &DI : MRI->def_instructions(VirtReg))
+ if (!DI.isImplicitDef())
return false;
return true;
}
findPHICopyInsertPoint(&opBlock, &MBB, SrcReg);
// Insert the copy.
- MachineInstr *NewSrcInstr = 0;
+ MachineInstr *NewSrcInstr = nullptr;
if (!reusedIncoming && IncomingReg) {
if (SrcUndef) {
// The source register is undefined, so there is no need for a real
/// used later to determine when the vreg is killed in the BB.
///
void PHIElimination::analyzePHINodes(const MachineFunction& MF) {
- for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
- I != E; ++I)
- for (MachineBasicBlock::const_iterator BBI = I->begin(), BBE = I->end();
- BBI != BBE && BBI->isPHI(); ++BBI)
- for (unsigned i = 1, e = BBI->getNumOperands(); i != e; i += 2)
- ++VRegPHIUseCount[BBVRegPair(BBI->getOperand(i+1).getMBB()->getNumber(),
- BBI->getOperand(i).getReg())];
+ for (const auto &MBB : MF)
+ for (const auto &BBI : MBB) {
+ if (!BBI.isPHI())
+ break;
+ for (unsigned i = 1, e = BBI.getNumOperands(); i != e; i += 2)
+ ++VRegPHIUseCount[BBVRegPair(BBI.getOperand(i+1).getMBB()->getNumber(),
+ BBI.getOperand(i).getReg())];
+ }
}
bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
if (MBB.empty() || !MBB.front().isPHI() || MBB.isLandingPad())
return false; // Quick exit for basic blocks without PHIs.
- const MachineLoop *CurLoop = MLI ? MLI->getLoopFor(&MBB) : 0;
+ const MachineLoop *CurLoop = MLI ? MLI->getLoopFor(&MBB) : nullptr;
bool IsLoopHeader = CurLoop && &MBB == CurLoop->getHeader();
bool Changed = false;
// out-of-line blocks into the loop which is very bad for code placement.
if (PreMBB == &MBB && !SplitAllCriticalEdges)
continue;
- const MachineLoop *PreLoop = MLI ? MLI->getLoopFor(PreMBB) : 0;
+ const MachineLoop *PreLoop = MLI ? MLI->getLoopFor(PreMBB) : nullptr;
if (IsLoopHeader && PreLoop == CurLoop && !SplitAllCriticalEdges)
continue;