//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "systemz-elim-compare"
-
#include "SystemZTargetMachine.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
using namespace llvm;
+#define DEBUG_TYPE "systemz-elim-compare"
+
STATISTIC(BranchOnCounts, "Number of branch-on-count instructions");
STATISTIC(EliminatedComparisons, "Number of eliminated comparisons");
STATISTIC(FusedComparisons, "Number of fused compare-and-branch instructions");
namespace {
- // Represents the references to a particular register in one or more
- // instructions.
- struct Reference {
- Reference()
- : Def(false), Use(false), IndirectDef(false), IndirectUse(false) {}
-
- Reference &operator|=(const Reference &Other) {
- Def |= Other.Def;
- IndirectDef |= Other.IndirectDef;
- Use |= Other.Use;
- IndirectUse |= Other.IndirectUse;
- return *this;
- }
+// Represents the references to a particular register in one or more
+// instructions.
+struct Reference {
+ Reference()
+ : Def(false), Use(false), IndirectDef(false), IndirectUse(false) {}
+
+ Reference &operator|=(const Reference &Other) {
+ Def |= Other.Def;
+ IndirectDef |= Other.IndirectDef;
+ Use |= Other.Use;
+ IndirectUse |= Other.IndirectUse;
+ return *this;
+ }
- operator bool() const { return Def || Use; }
+ LLVM_EXPLICIT operator bool() const { return Def || Use; }
- // True if the register is defined or used in some form, either directly or
- // via a sub- or super-register.
- bool Def;
- bool Use;
+ // True if the register is defined or used in some form, either directly or
+ // via a sub- or super-register.
+ bool Def;
+ bool Use;
- // True if the register is defined or used indirectly, by a sub- or
- // super-register.
- bool IndirectDef;
- bool IndirectUse;
- };
+ // True if the register is defined or used indirectly, by a sub- or
+ // super-register.
+ bool IndirectDef;
+ bool IndirectUse;
+};
- class SystemZElimCompare : public MachineFunctionPass {
- public:
- static char ID;
- SystemZElimCompare(const SystemZTargetMachine &tm)
- : MachineFunctionPass(ID), TII(0), TRI(0) {}
+class SystemZElimCompare : public MachineFunctionPass {
+public:
+ static char ID;
+ SystemZElimCompare(const SystemZTargetMachine &tm)
+ : MachineFunctionPass(ID), TII(nullptr), TRI(nullptr) {}
- virtual const char *getPassName() const {
- return "SystemZ Comparison Elimination";
- }
+ const char *getPassName() const override {
+ return "SystemZ Comparison Elimination";
+ }
+
+ bool processBlock(MachineBasicBlock &MBB);
+ bool runOnMachineFunction(MachineFunction &F) override;
- bool processBlock(MachineBasicBlock *MBB);
- bool runOnMachineFunction(MachineFunction &F);
-
- private:
- Reference getRegReferences(MachineInstr *MI, unsigned Reg);
- bool convertToBRCT(MachineInstr *MI, MachineInstr *Compare,
- SmallVectorImpl<MachineInstr *> &CCUsers);
- bool convertToLoadAndTest(MachineInstr *MI);
- bool adjustCCMasksForInstr(MachineInstr *MI, MachineInstr *Compare,
- SmallVectorImpl<MachineInstr *> &CCUsers);
- bool optimizeCompareZero(MachineInstr *Compare,
+private:
+ Reference getRegReferences(MachineInstr *MI, unsigned Reg);
+ bool convertToBRCT(MachineInstr *MI, MachineInstr *Compare,
+ SmallVectorImpl<MachineInstr *> &CCUsers);
+ bool convertToLoadAndTest(MachineInstr *MI);
+ bool adjustCCMasksForInstr(MachineInstr *MI, MachineInstr *Compare,
SmallVectorImpl<MachineInstr *> &CCUsers);
- bool fuseCompareAndBranch(MachineInstr *Compare,
- SmallVectorImpl<MachineInstr *> &CCUsers);
+ bool optimizeCompareZero(MachineInstr *Compare,
+ SmallVectorImpl<MachineInstr *> &CCUsers);
+ bool fuseCompareAndBranch(MachineInstr *Compare,
+ SmallVectorImpl<MachineInstr *> &CCUsers);
- const SystemZInstrInfo *TII;
- const TargetRegisterInfo *TRI;
- };
+ const SystemZInstrInfo *TII;
+ const TargetRegisterInfo *TRI;
+};
- char SystemZElimCompare::ID = 0;
-} // end of anonymous namespace
+char SystemZElimCompare::ID = 0;
+} // end anonymous namespace
FunctionPass *llvm::createSystemZElimComparePass(SystemZTargetMachine &TM) {
return new SystemZElimCompare(TM);
}
// Return true if CC is live out of MBB.
-static bool isCCLiveOut(MachineBasicBlock *MBB) {
- for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(),
- SE = MBB->succ_end(); SI != SE; ++SI)
+static bool isCCLiveOut(MachineBasicBlock &MBB) {
+ for (auto SI = MBB.succ_begin(), SE = MBB.succ_end(); SI != SE; ++SI)
if ((*SI)->isLiveIn(SystemZ::CC))
return true;
return false;
// Search back for CC results that are based on the first operand.
unsigned SrcReg = Compare->getOperand(0).getReg();
unsigned SrcSubReg = Compare->getOperand(0).getSubReg();
- MachineBasicBlock *MBB = Compare->getParent();
- MachineBasicBlock::iterator MBBI = Compare, MBBE = MBB->begin();
+ MachineBasicBlock &MBB = *Compare->getParent();
+ MachineBasicBlock::iterator MBBI = Compare, MBBE = MBB.begin();
Reference CCRefs;
Reference SrcRefs;
while (MBBI != MBBE) {
// Process all comparison instructions in MBB. Return true if something
// changed.
-bool SystemZElimCompare::processBlock(MachineBasicBlock *MBB) {
+bool SystemZElimCompare::processBlock(MachineBasicBlock &MBB) {
bool Changed = false;
// Walk backwards through the block looking for comparisons, recording
// instructions before it.
bool CompleteCCUsers = !isCCLiveOut(MBB);
SmallVector<MachineInstr *, 4> CCUsers;
- MachineBasicBlock::iterator MBBI = MBB->end();
- while (MBBI != MBB->begin()) {
+ MachineBasicBlock::iterator MBBI = MBB.end();
+ while (MBBI != MBB.begin()) {
MachineInstr *MI = --MBBI;
if (CompleteCCUsers &&
MI->isCompare() &&
}
bool SystemZElimCompare::runOnMachineFunction(MachineFunction &F) {
- TII = static_cast<const SystemZInstrInfo *>(F.getTarget().getInstrInfo());
+ TII = static_cast<const SystemZInstrInfo *>(F.getSubtarget().getInstrInfo());
TRI = &TII->getRegisterInfo();
bool Changed = false;
- for (MachineFunction::iterator MFI = F.begin(), MFE = F.end();
- MFI != MFE; ++MFI)
- Changed |= processBlock(MFI);
+ for (auto &MBB : F)
+ Changed |= processBlock(MBB);
return Changed;
}
projects / oota-llvm.git / blobdiff