#include "ARM.h"
#include "ARMMachineFunctionInfo.h"
#include "Thumb2InstrInfo.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineInstrBundle.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/ADT/SmallSet.h"
-#include "llvm/ADT/Statistic.h"
using namespace llvm;
STATISTIC(NumITs, "Number of IT blocks inserted");
namespace {
class Thumb2ITBlockPass : public MachineFunctionPass {
- bool PreRegAlloc;
-
public:
static char ID;
Thumb2ITBlockPass() : MachineFunctionPass(ID) {}
+ bool restrictIT;
const Thumb2InstrInfo *TII;
const TargetRegisterInfo *TRI;
ARMFunctionInfo *AFI;
for (unsigned i = 0, e = LocalUses.size(); i != e; ++i) {
unsigned Reg = LocalUses[i];
- Uses.insert(Reg);
- for (const uint16_t *Subreg = TRI->getSubRegisters(Reg);
- *Subreg; ++Subreg)
+ for (MCSubRegIterator Subreg(Reg, TRI, /*IncludeSelf=*/true);
+ Subreg.isValid(); ++Subreg)
Uses.insert(*Subreg);
}
for (unsigned i = 0, e = LocalDefs.size(); i != e; ++i) {
unsigned Reg = LocalDefs[i];
- Defs.insert(Reg);
- for (const uint16_t *Subreg = TRI->getSubRegisters(Reg);
- *Subreg; ++Subreg)
+ for (MCSubRegIterator Subreg(Reg, TRI, /*IncludeSelf=*/true);
+ Subreg.isValid(); ++Subreg)
Defs.insert(*Subreg);
if (Reg == ARM::CPSR)
continue;
// Form IT block.
ARMCC::CondCodes OCC = ARMCC::getOppositeCondition(CC);
unsigned Mask = 0, Pos = 3;
- // Branches, including tricky ones like LDM_RET, need to end an IT
- // block so check the instruction we just put in the block.
- for (; MBBI != E && Pos &&
- (!MI->isBranch() && !MI->isReturn()) ; ++MBBI) {
- if (MBBI->isDebugValue())
- continue;
-
- MachineInstr *NMI = &*MBBI;
- MI = NMI;
-
- unsigned NPredReg = 0;
- ARMCC::CondCodes NCC = getITInstrPredicate(NMI, NPredReg);
- if (NCC == CC || NCC == OCC) {
- Mask |= (NCC & 1) << Pos;
- // Add implicit use of ITSTATE.
- NMI->addOperand(MachineOperand::CreateReg(ARM::ITSTATE, false/*ifDef*/,
- true/*isImp*/, false/*isKill*/));
- LastITMI = NMI;
- } else {
- if (NCC == ARMCC::AL &&
- MoveCopyOutOfITBlock(NMI, CC, OCC, Defs, Uses)) {
- --MBBI;
- MBB.remove(NMI);
- MBB.insert(InsertPos, NMI);
- ++NumMovedInsts;
+
+ // v8 IT blocks are limited to one conditional op unless -arm-no-restrict-it
+ // is set: skip the loop
+ if (!restrictIT) {
+ // Branches, including tricky ones like LDM_RET, need to end an IT
+ // block so check the instruction we just put in the block.
+ for (; MBBI != E && Pos &&
+ (!MI->isBranch() && !MI->isReturn()) ; ++MBBI) {
+ if (MBBI->isDebugValue())
continue;
+
+ MachineInstr *NMI = &*MBBI;
+ MI = NMI;
+
+ unsigned NPredReg = 0;
+ ARMCC::CondCodes NCC = getITInstrPredicate(NMI, NPredReg);
+ if (NCC == CC || NCC == OCC) {
+ Mask |= (NCC & 1) << Pos;
+ // Add implicit use of ITSTATE.
+ NMI->addOperand(MachineOperand::CreateReg(ARM::ITSTATE, false/*ifDef*/,
+ true/*isImp*/, false/*isKill*/));
+ LastITMI = NMI;
+ } else {
+ if (NCC == ARMCC::AL &&
+ MoveCopyOutOfITBlock(NMI, CC, OCC, Defs, Uses)) {
+ --MBBI;
+ MBB.remove(NMI);
+ MBB.insert(InsertPos, NMI);
+ ++NumMovedInsts;
+ continue;
+ }
+ break;
}
- break;
+ TrackDefUses(NMI, Defs, Uses, TRI);
+ --Pos;
}
- TrackDefUses(NMI, Defs, Uses, TRI);
- --Pos;
}
// Finalize IT mask.
AFI = Fn.getInfo<ARMFunctionInfo>();
TII = static_cast<const Thumb2InstrInfo*>(TM.getInstrInfo());
TRI = TM.getRegisterInfo();
+ restrictIT = TM.getSubtarget<ARMSubtarget>().restrictIT();
if (!AFI->isThumbFunction())
return false;