// C = copy A <-- same-bank copy
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "peephole-opt"
#include "llvm/CodeGen/Passes.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
+#define DEBUG_TYPE "peephole-opt"
+
// Optimize Extensions
static cl::opt<bool>
Aggressive("aggressive-ext-opt", cl::Hidden,
bool foldImmediate(MachineInstr *MI, MachineBasicBlock *MBB,
SmallSet<unsigned, 4> &ImmDefRegs,
DenseMap<unsigned, MachineInstr*> &ImmDefMIs);
- bool isLoadFoldable(MachineInstr *MI, unsigned &FoldAsLoadDefReg);
+ bool isLoadFoldable(MachineInstr *MI,
+ SmallSet<unsigned, 16> &FoldAsLoadDefCandidates);
};
}
// If UseSrcSubIdx is Set, SubIdx also applies to SrcReg, and only uses of
// SrcReg:SubIdx should be replaced.
bool UseSrcSubIdx = TM->getRegisterInfo()->
- getSubClassWithSubReg(MRI->getRegClass(SrcReg), SubIdx) != 0;
+ getSubClassWithSubReg(MRI->getRegClass(SrcReg), SubIdx) != nullptr;
// The source has other uses. See if we can replace the other uses with use of
// the result of the extension.
SmallPtrSet<MachineBasicBlock*, 4> ReachedBBs;
- for (MachineRegisterInfo::use_nodbg_iterator
- UI = MRI->use_nodbg_begin(DstReg), UE = MRI->use_nodbg_end();
- UI != UE; ++UI)
- ReachedBBs.insert(UI->getParent());
+ for (MachineInstr &UI : MRI->use_nodbg_instructions(DstReg))
+ ReachedBBs.insert(UI.getParent());
// Uses that are in the same BB of uses of the result of the instruction.
SmallVector<MachineOperand*, 8> Uses;
SmallVector<MachineOperand*, 8> ExtendedUses;
bool ExtendLife = true;
- for (MachineRegisterInfo::use_nodbg_iterator
- UI = MRI->use_nodbg_begin(SrcReg), UE = MRI->use_nodbg_end();
- UI != UE; ++UI) {
- MachineOperand &UseMO = UI.getOperand();
- MachineInstr *UseMI = &*UI;
+ for (MachineOperand &UseMO : MRI->use_nodbg_operands(SrcReg)) {
+ MachineInstr *UseMI = UseMO.getParent();
if (UseMI == MI)
continue;
// Look for PHI uses of the extended result, we don't want to extend the
// liveness of a PHI input. It breaks all kinds of assumptions down
// stream. A PHI use is expected to be the kill of its source values.
- for (MachineRegisterInfo::use_nodbg_iterator
- UI = MRI->use_nodbg_begin(DstReg), UE = MRI->use_nodbg_end();
- UI != UE; ++UI)
- if (UI->isPHI())
- PHIBBs.insert(UI->getParent());
+ for (MachineInstr &UI : MRI->use_nodbg_instructions(DstReg))
+ if (UI.isPHI())
+ PHIBBs.insert(UI.getParent());
const TargetRegisterClass *RC = MRI->getRegClass(SrcReg);
for (unsigned i = 0, e = Uses.size(); i != e; ++i) {
unsigned SrcIdx, DefIdx;
if (SrcSubReg && DefSubReg)
return TRI.getCommonSuperRegClass(SrcRC, SrcSubReg, DefRC, DefSubReg,
- SrcIdx, DefIdx) != NULL;
+ SrcIdx, DefIdx) != nullptr;
// At most one of the register is a sub register, make it Src to avoid
// duplicating the test.
if (!SrcSubReg) {
// One of the register is a sub register, check if we can get a superclass.
if (SrcSubReg)
- return TRI.getMatchingSuperRegClass(SrcRC, DefRC, SrcSubReg) != NULL;
+ return TRI.getMatchingSuperRegClass(SrcRC, DefRC, SrcSubReg) != nullptr;
// Plain copy.
- return TRI.getCommonSubClass(DefRC, SrcRC) != NULL;
+ return TRI.getCommonSubClass(DefRC, SrcRC) != nullptr;
}
/// \brief Get the index of the definition and source for \p Copy
/// isLoadFoldable - Check whether MI is a candidate for folding into a later
/// instruction. We only fold loads to virtual registers and the virtual
/// register defined has a single use.
-bool PeepholeOptimizer::isLoadFoldable(MachineInstr *MI,
- unsigned &FoldAsLoadDefReg) {
+bool PeepholeOptimizer::isLoadFoldable(
+ MachineInstr *MI,
+ SmallSet<unsigned, 16> &FoldAsLoadDefCandidates) {
if (!MI->canFoldAsLoad() || !MI->mayLoad())
return false;
const MCInstrDesc &MCID = MI->getDesc();
if (!MI->getOperand(0).getSubReg() &&
TargetRegisterInfo::isVirtualRegister(Reg) &&
MRI->hasOneNonDBGUse(Reg)) {
- FoldAsLoadDefReg = Reg;
+ FoldAsLoadDefCandidates.insert(Reg);
return true;
}
return false;
}
bool PeepholeOptimizer::runOnMachineFunction(MachineFunction &MF) {
+ if (skipOptnoneFunction(*MF.getFunction()))
+ return false;
+
DEBUG(dbgs() << "********** PEEPHOLE OPTIMIZER **********\n");
DEBUG(dbgs() << "********** Function: " << MF.getName() << '\n');
TM = &MF.getTarget();
TII = TM->getInstrInfo();
MRI = &MF.getRegInfo();
- DT = Aggressive ? &getAnalysis<MachineDominatorTree>() : 0;
+ DT = Aggressive ? &getAnalysis<MachineDominatorTree>() : nullptr;
bool Changed = false;
- SmallPtrSet<MachineInstr*, 8> LocalMIs;
- SmallSet<unsigned, 4> ImmDefRegs;
- DenseMap<unsigned, MachineInstr*> ImmDefMIs;
- unsigned FoldAsLoadDefReg;
for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) {
MachineBasicBlock *MBB = &*I;
bool SeenMoveImm = false;
- LocalMIs.clear();
- ImmDefRegs.clear();
- ImmDefMIs.clear();
- FoldAsLoadDefReg = 0;
+ SmallPtrSet<MachineInstr*, 8> LocalMIs;
+ SmallSet<unsigned, 4> ImmDefRegs;
+ DenseMap<unsigned, MachineInstr*> ImmDefMIs;
+ SmallSet<unsigned, 16> FoldAsLoadDefCandidates;
for (MachineBasicBlock::iterator
MII = I->begin(), MIE = I->end(); MII != MIE; ) {
continue;
// If there exists an instruction which belongs to the following
- // categories, we will discard the load candidate.
+ // categories, we will discard the load candidates.
if (MI->isPosition() || MI->isPHI() || MI->isImplicitDef() ||
MI->isKill() || MI->isInlineAsm() ||
MI->hasUnmodeledSideEffects()) {
- FoldAsLoadDefReg = 0;
+ FoldAsLoadDefCandidates.clear();
continue;
}
if (MI->mayStore() || MI->isCall())
- FoldAsLoadDefReg = 0;
+ FoldAsLoadDefCandidates.clear();
if (((MI->isBitcast() || MI->isCopy()) && optimizeCopyOrBitcast(MI)) ||
(MI->isCompare() && optimizeCmpInstr(MI, MBB)) ||
// Check whether MI is a load candidate for folding into a later
// instruction. If MI is not a candidate, check whether we can fold an
// earlier load into MI.
- if (!isLoadFoldable(MI, FoldAsLoadDefReg) && FoldAsLoadDefReg) {
- // We need to fold load after optimizeCmpInstr, since optimizeCmpInstr
- // can enable folding by converting SUB to CMP.
- // Save FoldAsLoadDefReg because optimizeLoadInstr() resets it and we
- // need it for markUsesInDebugValueAsUndef().
- unsigned FoldedReg = FoldAsLoadDefReg;
- MachineInstr *DefMI = 0;
- MachineInstr *FoldMI = TII->optimizeLoadInstr(MI, MRI,
- FoldAsLoadDefReg, DefMI);
- if (FoldMI) {
- // Update LocalMIs since we replaced MI with FoldMI and deleted DefMI.
- DEBUG(dbgs() << "Replacing: " << *MI);
- DEBUG(dbgs() << " With: " << *FoldMI);
- LocalMIs.erase(MI);
- LocalMIs.erase(DefMI);
- LocalMIs.insert(FoldMI);
- MI->eraseFromParent();
- DefMI->eraseFromParent();
- MRI->markUsesInDebugValueAsUndef(FoldedReg);
- ++NumLoadFold;
-
- // MI is replaced with FoldMI.
- Changed = true;
- continue;
+ if (!isLoadFoldable(MI, FoldAsLoadDefCandidates) &&
+ !FoldAsLoadDefCandidates.empty()) {
+ const MCInstrDesc &MIDesc = MI->getDesc();
+ for (unsigned i = MIDesc.getNumDefs(); i != MIDesc.getNumOperands();
+ ++i) {
+ const MachineOperand &MOp = MI->getOperand(i);
+ if (!MOp.isReg())
+ continue;
+ unsigned FoldAsLoadDefReg = MOp.getReg();
+ if (FoldAsLoadDefCandidates.count(FoldAsLoadDefReg)) {
+ // We need to fold load after optimizeCmpInstr, since
+ // optimizeCmpInstr can enable folding by converting SUB to CMP.
+ // Save FoldAsLoadDefReg because optimizeLoadInstr() resets it and
+ // we need it for markUsesInDebugValueAsUndef().
+ unsigned FoldedReg = FoldAsLoadDefReg;
+ MachineInstr *DefMI = nullptr;
+ MachineInstr *FoldMI = TII->optimizeLoadInstr(MI, MRI,
+ FoldAsLoadDefReg,
+ DefMI);
+ if (FoldMI) {
+ // Update LocalMIs since we replaced MI with FoldMI and deleted
+ // DefMI.
+ DEBUG(dbgs() << "Replacing: " << *MI);
+ DEBUG(dbgs() << " With: " << *FoldMI);
+ LocalMIs.erase(MI);
+ LocalMIs.erase(DefMI);
+ LocalMIs.insert(FoldMI);
+ MI->eraseFromParent();
+ DefMI->eraseFromParent();
+ MRI->markUsesInDebugValueAsUndef(FoldedReg);
+ FoldAsLoadDefCandidates.erase(FoldedReg);
+ ++NumLoadFold;
+ // MI is replaced with FoldMI.
+ Changed = true;
+ break;
+ }
+ }
}
}
}
projects / oota-llvm.git / blobdiff