return Base.Reg;
}
void setOffsetReg(unsigned Reg) {
- assert(isRegBase() && "Invalid offset register access!");
OffsetReg = Reg;
}
unsigned getOffsetReg() const {
- assert(isRegBase() && "Invalid offset register access!");
return OffsetReg;
}
void setFI(unsigned FI) {
bool selectBitCast(const Instruction *I);
bool selectFRem(const Instruction *I);
bool selectSDiv(const Instruction *I);
+ bool selectGetElementPtr(const Instruction *I);
// Utility helper routines.
bool isTypeLegal(Type *Ty, MVT &VT);
unsigned Alignment);
bool foldXALUIntrinsic(AArch64CC::CondCode &CC, const Instruction *I,
const Value *Cond);
+ bool optimizeIntExtLoad(const Instruction *I, MVT RetVT, MVT SrcVT);
// Emit helper routines.
unsigned emitAddSub(bool UseAdd, MVT RetVT, const Value *LHS,
bool WantResult = true);
// Emit functions.
+ bool emitCompareAndBranch(const BranchInst *BI);
bool emitCmp(const Value *LHS, const Value *RHS, bool IsZExt);
bool emitICmp(MVT RetVT, const Value *LHS, const Value *RHS, bool IsZExt);
bool emitICmp_ri(MVT RetVT, unsigned LHSReg, bool LHSIsKill, uint64_t Imm);
bool emitFCmp(MVT RetVT, const Value *LHS, const Value *RHS);
- bool emitLoad(MVT VT, unsigned &ResultReg, Address Addr, bool WantZExt = true,
- MachineMemOperand *MMO = nullptr);
+ unsigned emitLoad(MVT VT, MVT ResultVT, Address Addr, bool WantZExt = true,
+ MachineMemOperand *MMO = nullptr);
bool emitStore(MVT VT, unsigned SrcReg, Address Addr,
MachineMemOperand *MMO = nullptr);
unsigned emitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, bool isZExt);
unsigned emitAdd(MVT RetVT, const Value *LHS, const Value *RHS,
bool SetFlags = false, bool WantResult = true,
bool IsZExt = false);
+ unsigned emitAdd_ri_(MVT VT, unsigned Op0, bool Op0IsKill, int64_t Imm);
unsigned emitSub(MVT RetVT, const Value *LHS, const Value *RHS,
bool SetFlags = false, bool WantResult = true,
bool IsZExt = false);
static bool isIntExtFree(const Instruction *I) {
assert((isa<ZExtInst>(I) || isa<SExtInst>(I)) &&
"Unexpected integer extend instruction.");
+ assert(!I->getType()->isVectorTy() && I->getType()->isIntegerTy() &&
+ "Unexpected value type.");
bool IsZExt = isa<ZExtInst>(I);
if (const auto *LI = dyn_cast<LoadInst>(I->getOperand(0)))
std::swap(LHS, RHS);
if (const ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
- Addr.setOffset(Addr.getOffset() + (uint64_t)CI->getSExtValue());
+ Addr.setOffset(Addr.getOffset() + CI->getSExtValue());
return computeAddress(LHS, Addr, Ty);
}
break;
}
+ case Instruction::Sub: {
+ // Subs of constants are common and easy enough.
+ const Value *LHS = U->getOperand(0);
+ const Value *RHS = U->getOperand(1);
+
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
+ Addr.setOffset(Addr.getOffset() - CI->getSExtValue());
+ return computeAddress(LHS, Addr, Ty);
+ }
+ break;
+ }
case Instruction::Shl: {
if (Addr.getOffsetReg())
break;
}
break;
}
- } // end switch
+ case Instruction::SExt:
+ case Instruction::ZExt: {
+ if (!Addr.getReg() || Addr.getOffsetReg())
+ break;
- if (Addr.getReg()) {
- if (!Addr.getOffsetReg()) {
- unsigned Reg = getRegForValue(Obj);
- if (!Reg)
- return false;
- Addr.setOffsetReg(Reg);
- return true;
+ const Value *Src = nullptr;
+ // Fold the zext or sext when it won't become a noop.
+ if (const auto *ZE = dyn_cast<ZExtInst>(U)) {
+ if (!isIntExtFree(ZE) && ZE->getOperand(0)->getType()->isIntegerTy(32)) {
+ Addr.setExtendType(AArch64_AM::UXTW);
+ Src = ZE->getOperand(0);
+ }
+ } else if (const auto *SE = dyn_cast<SExtInst>(U)) {
+ if (!isIntExtFree(SE) && SE->getOperand(0)->getType()->isIntegerTy(32)) {
+ Addr.setExtendType(AArch64_AM::SXTW);
+ Src = SE->getOperand(0);
+ }
}
- return false;
+
+ if (!Src)
+ break;
+
+ Addr.setShift(0);
+ unsigned Reg = getRegForValue(Src);
+ if (!Reg)
+ return false;
+ Addr.setOffsetReg(Reg);
+ return true;
}
+ } // end switch
- unsigned Reg = getRegForValue(Obj);
- if (!Reg)
- return false;
- Addr.setReg(Reg);
- return true;
+ if (Addr.isRegBase() && !Addr.getReg()) {
+ unsigned Reg = getRegForValue(Obj);
+ if (!Reg)
+ return false;
+ Addr.setReg(Reg);
+ return true;
+ }
+
+ if (!Addr.getOffsetReg()) {
+ unsigned Reg = getRegForValue(Obj);
+ if (!Reg)
+ return false;
+ Addr.setOffsetReg(Reg);
+ return true;
+ }
+
+ return false;
}
bool AArch64FastISel::computeCallAddress(const Value *V, Address &Addr) {
// Cannot encode an offset register and an immediate offset in the same
// instruction. Fold the immediate offset into the load/store instruction and
// emit an additonal add to take care of the offset register.
- if (!ImmediateOffsetNeedsLowering && Addr.getOffset() && Addr.isRegBase() &&
- Addr.getOffsetReg())
+ if (!ImmediateOffsetNeedsLowering && Addr.getOffset() && Addr.getOffsetReg())
RegisterOffsetNeedsLowering = true;
// Cannot encode zero register as base.
// If this is a stack pointer and the offset needs to be simplified then put
// the alloca address into a register, set the base type back to register and
// continue. This should almost never happen.
- if (ImmediateOffsetNeedsLowering && Addr.isFIBase()) {
+ if ((ImmediateOffsetNeedsLowering || Addr.getOffsetReg()) && Addr.isFIBase())
+ {
unsigned ResultReg = createResultReg(&AArch64::GPR64spRegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(AArch64::ADDXri),
ResultReg)
// reg+offset into a register.
if (ImmediateOffsetNeedsLowering) {
unsigned ResultReg;
- if (Addr.getReg()) {
+ if (Addr.getReg())
// Try to fold the immediate into the add instruction.
- if (Offset < 0)
- ResultReg = emitAddSub_ri(/*UseAdd=*/false, MVT::i64, Addr.getReg(),
- /*IsKill=*/false, -Offset);
- else
- ResultReg = emitAddSub_ri(/*UseAdd=*/true, MVT::i64, Addr.getReg(),
- /*IsKill=*/false, Offset);
- if (!ResultReg) {
- unsigned ImmReg = fastEmit_i(MVT::i64, MVT::i64, ISD::Constant, Offset);
- ResultReg = emitAddSub_rr(/*UseAdd=*/true, MVT::i64, Addr.getReg(),
- /*IsKill=*/false, ImmReg, /*IsKill=*/true);
- }
- } else
+ ResultReg = emitAdd_ri_(MVT::i64, Addr.getReg(), /*IsKill=*/false, Offset);
+ else
ResultReg = fastEmit_i(MVT::i64, MVT::i64, ISD::Constant, Offset);
if (!ResultReg)
MIB.addReg(Addr.getOffsetReg());
MIB.addImm(IsSigned);
MIB.addImm(Addr.getShift() != 0);
- } else {
- MIB.addReg(Addr.getReg());
- MIB.addImm(Offset);
- }
+ } else
+ MIB.addReg(Addr.getReg()).addImm(Offset);
}
if (MMO)
IsZExt);
}
+/// \brief This method is a wrapper to simplify add emission.
+///
+/// First try to emit an add with an immediate operand using emitAddSub_ri. If
+/// that fails, then try to materialize the immediate into a register and use
+/// emitAddSub_rr instead.
+unsigned AArch64FastISel::emitAdd_ri_(MVT VT, unsigned Op0, bool Op0IsKill,
+ int64_t Imm) {
+ unsigned ResultReg;
+ if (Imm < 0)
+ ResultReg = emitAddSub_ri(false, VT, Op0, Op0IsKill, -Imm);
+ else
+ ResultReg = emitAddSub_ri(true, VT, Op0, Op0IsKill, Imm);
+
+ if (ResultReg)
+ return ResultReg;
+
+ unsigned CReg = fastEmit_i(VT, VT, ISD::Constant, Imm);
+ if (!CReg)
+ return 0;
+
+ ResultReg = emitAddSub_rr(true, VT, Op0, Op0IsKill, CReg, true);
+ return ResultReg;
+}
+
unsigned AArch64FastISel::emitSub(MVT RetVT, const Value *LHS, const Value *RHS,
bool SetFlags, bool WantResult, bool IsZExt) {
return emitAddSub(/*UseAdd=*/false, RetVT, LHS, RHS, SetFlags, WantResult,
return emitLogicalOp_ri(ISD::AND, RetVT, LHSReg, LHSIsKill, Imm);
}
-bool AArch64FastISel::emitLoad(MVT VT, unsigned &ResultReg, Address Addr,
- bool WantZExt, MachineMemOperand *MMO) {
+unsigned AArch64FastISel::emitLoad(MVT VT, MVT RetVT, Address Addr,
+ bool WantZExt, MachineMemOperand *MMO) {
// Simplify this down to something we can handle.
if (!simplifyAddress(Addr, VT))
- return false;
+ return 0;
unsigned ScaleFactor = getImplicitScaleFactor(VT);
if (!ScaleFactor)
ScaleFactor = 1;
}
- static const unsigned GPOpcTable[2][4][4] = {
+ static const unsigned GPOpcTable[2][8][4] = {
// Sign-extend.
- { { AArch64::LDURSBWi, AArch64::LDURSHWi, AArch64::LDURSWi,
+ { { AArch64::LDURSBWi, AArch64::LDURSHWi, AArch64::LDURWi,
AArch64::LDURXi },
- { AArch64::LDRSBWui, AArch64::LDRSHWui, AArch64::LDRSWui,
+ { AArch64::LDURSBXi, AArch64::LDURSHXi, AArch64::LDURSWi,
+ AArch64::LDURXi },
+ { AArch64::LDRSBWui, AArch64::LDRSHWui, AArch64::LDRWui,
+ AArch64::LDRXui },
+ { AArch64::LDRSBXui, AArch64::LDRSHXui, AArch64::LDRSWui,
AArch64::LDRXui },
- { AArch64::LDRSBWroX, AArch64::LDRSHWroX, AArch64::LDRSWroX,
+ { AArch64::LDRSBWroX, AArch64::LDRSHWroX, AArch64::LDRWroX,
AArch64::LDRXroX },
- { AArch64::LDRSBWroW, AArch64::LDRSHWroW, AArch64::LDRSWroW,
+ { AArch64::LDRSBXroX, AArch64::LDRSHXroX, AArch64::LDRSWroX,
+ AArch64::LDRXroX },
+ { AArch64::LDRSBWroW, AArch64::LDRSHWroW, AArch64::LDRWroW,
AArch64::LDRXroW },
+ { AArch64::LDRSBXroW, AArch64::LDRSHXroW, AArch64::LDRSWroW,
+ AArch64::LDRXroW }
},
// Zero-extend.
{ { AArch64::LDURBBi, AArch64::LDURHHi, AArch64::LDURWi,
AArch64::LDURXi },
+ { AArch64::LDURBBi, AArch64::LDURHHi, AArch64::LDURWi,
+ AArch64::LDURXi },
{ AArch64::LDRBBui, AArch64::LDRHHui, AArch64::LDRWui,
AArch64::LDRXui },
+ { AArch64::LDRBBui, AArch64::LDRHHui, AArch64::LDRWui,
+ AArch64::LDRXui },
+ { AArch64::LDRBBroX, AArch64::LDRHHroX, AArch64::LDRWroX,
+ AArch64::LDRXroX },
{ AArch64::LDRBBroX, AArch64::LDRHHroX, AArch64::LDRWroX,
AArch64::LDRXroX },
+ { AArch64::LDRBBroW, AArch64::LDRHHroW, AArch64::LDRWroW,
+ AArch64::LDRXroW },
{ AArch64::LDRBBroW, AArch64::LDRHHroW, AArch64::LDRWroW,
AArch64::LDRXroW }
}
Addr.getExtendType() == AArch64_AM::SXTW)
Idx++;
+ bool IsRet64Bit = RetVT == MVT::i64;
switch (VT.SimpleTy) {
default:
llvm_unreachable("Unexpected value type.");
case MVT::i1: // Intentional fall-through.
case MVT::i8:
- Opc = GPOpcTable[WantZExt][Idx][0];
- RC = &AArch64::GPR32RegClass;
+ Opc = GPOpcTable[WantZExt][2 * Idx + IsRet64Bit][0];
+ RC = (IsRet64Bit && !WantZExt) ?
+ &AArch64::GPR64RegClass: &AArch64::GPR32RegClass;
break;
case MVT::i16:
- Opc = GPOpcTable[WantZExt][Idx][1];
- RC = &AArch64::GPR32RegClass;
+ Opc = GPOpcTable[WantZExt][2 * Idx + IsRet64Bit][1];
+ RC = (IsRet64Bit && !WantZExt) ?
+ &AArch64::GPR64RegClass: &AArch64::GPR32RegClass;
break;
case MVT::i32:
- Opc = GPOpcTable[WantZExt][Idx][2];
- RC = WantZExt ? &AArch64::GPR32RegClass : &AArch64::GPR64RegClass;
+ Opc = GPOpcTable[WantZExt][2 * Idx + IsRet64Bit][2];
+ RC = (IsRet64Bit && !WantZExt) ?
+ &AArch64::GPR64RegClass: &AArch64::GPR32RegClass;
break;
case MVT::i64:
- Opc = GPOpcTable[WantZExt][Idx][3];
+ Opc = GPOpcTable[WantZExt][2 * Idx + IsRet64Bit][3];
RC = &AArch64::GPR64RegClass;
break;
case MVT::f32:
}
// Create the base instruction, then add the operands.
- ResultReg = createResultReg(RC);
+ unsigned ResultReg = createResultReg(RC);
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(Opc), ResultReg);
addLoadStoreOperands(Addr, MIB, MachineMemOperand::MOLoad, ScaleFactor, MMO);
- // For 32bit loads we do sign-extending loads to 64bit and then extract the
- // subreg. In the end this is just a NOOP.
- if (VT == MVT::i32 && !WantZExt)
- ResultReg = fastEmitInst_extractsubreg(MVT::i32, ResultReg, /*IsKill=*/true,
- AArch64::sub_32);
-
// Loading an i1 requires special handling.
if (VT == MVT::i1) {
unsigned ANDReg = emitAnd_ri(MVT::i32, ResultReg, /*IsKill=*/true, 1);
assert(ANDReg && "Unexpected AND instruction emission failure.");
ResultReg = ANDReg;
}
- return true;
+
+ // For zero-extending loads to 64bit we emit a 32bit load and then convert
+ // the 32bit reg to a 64bit reg.
+ if (WantZExt && RetVT == MVT::i64 && VT <= MVT::i32) {
+ unsigned Reg64 = createResultReg(&AArch64::GPR64RegClass);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
+ TII.get(AArch64::SUBREG_TO_REG), Reg64)
+ .addImm(0)
+ .addReg(ResultReg, getKillRegState(true))
+ .addImm(AArch64::sub_32);
+ ResultReg = Reg64;
+ }
+ return ResultReg;
}
bool AArch64FastISel::selectAddSub(const Instruction *I) {
if (!computeAddress(I->getOperand(0), Addr, I->getType()))
return false;
+ // Fold the following sign-/zero-extend into the load instruction.
bool WantZExt = true;
- if (I->hasOneUse() && isa<SExtInst>(I->use_begin()->getUser()))
- WantZExt = false;
+ MVT RetVT = VT;
+ const Value *IntExtVal = nullptr;
+ if (I->hasOneUse()) {
+ if (const auto *ZE = dyn_cast<ZExtInst>(I->use_begin()->getUser())) {
+ if (isTypeSupported(ZE->getType(), RetVT))
+ IntExtVal = ZE;
+ else
+ RetVT = VT;
+ } else if (const auto *SE = dyn_cast<SExtInst>(I->use_begin()->getUser())) {
+ if (isTypeSupported(SE->getType(), RetVT))
+ IntExtVal = SE;
+ else
+ RetVT = VT;
+ WantZExt = false;
+ }
+ }
- unsigned ResultReg;
- if (!emitLoad(VT, ResultReg, Addr, WantZExt, createMachineMemOperandFor(I)))
+ unsigned ResultReg =
+ emitLoad(VT, RetVT, Addr, WantZExt, createMachineMemOperandFor(I));
+ if (!ResultReg)
return false;
+ // There are a few different cases we have to handle, because the load or the
+ // sign-/zero-extend might not be selected by FastISel if we fall-back to
+ // SelectionDAG. There is also an ordering issue when both instructions are in
+ // different basic blocks.
+ // 1.) The load instruction is selected by FastISel, but the integer extend
+ // not. This usually happens when the integer extend is in a different
+ // basic block and SelectionDAG took over for that basic block.
+ // 2.) The load instruction is selected before the integer extend. This only
+ // happens when the integer extend is in a different basic block.
+ // 3.) The load instruction is selected by SelectionDAG and the integer extend
+ // by FastISel. This happens if there are instructions between the load
+ // and the integer extend that couldn't be selected by FastISel.
+ if (IntExtVal) {
+ // The integer extend hasn't been emitted yet. FastISel or SelectionDAG
+ // could select it. Emit a copy to subreg if necessary. FastISel will remove
+ // it when it selects the integer extend.
+ unsigned Reg = lookUpRegForValue(IntExtVal);
+ if (!Reg) {
+ if (RetVT == MVT::i64 && VT <= MVT::i32) {
+ if (WantZExt) {
+ // Delete the last emitted instruction from emitLoad (SUBREG_TO_REG).
+ std::prev(FuncInfo.InsertPt)->eraseFromParent();
+ ResultReg = std::prev(FuncInfo.InsertPt)->getOperand(0).getReg();
+ } else
+ ResultReg = fastEmitInst_extractsubreg(MVT::i32, ResultReg,
+ /*IsKill=*/true,
+ AArch64::sub_32);
+ }
+ updateValueMap(I, ResultReg);
+ return true;
+ }
+
+ // The integer extend has already been emitted - delete all the instructions
+ // that have been emitted by the integer extend lowering code and use the
+ // result from the load instruction directly.
+ while (Reg) {
+ auto *MI = MRI.getUniqueVRegDef(Reg);
+ if (!MI)
+ break;
+ Reg = 0;
+ for (auto &Opnd : MI->uses()) {
+ if (Opnd.isReg()) {
+ Reg = Opnd.getReg();
+ break;
+ }
+ }
+ MI->eraseFromParent();
+ }
+ updateValueMap(IntExtVal, ResultReg);
+ return true;
+ }
+
updateValueMap(I, ResultReg);
return true;
}
}
}
-/// \brief Check if the comparison against zero and the following branch can be
-/// folded into a single instruction (CBZ or CBNZ).
-static bool canFoldZeroIntoBranch(const CmpInst *CI) {
- CmpInst::Predicate Predicate = CI->getPredicate();
- if ((Predicate != CmpInst::ICMP_EQ) && (Predicate != CmpInst::ICMP_NE))
- return false;
+/// \brief Try to emit a combined compare-and-branch instruction.
+bool AArch64FastISel::emitCompareAndBranch(const BranchInst *BI) {
+ assert(isa<CmpInst>(BI->getCondition()) && "Expected cmp instruction");
+ const CmpInst *CI = cast<CmpInst>(BI->getCondition());
+ CmpInst::Predicate Predicate = optimizeCmpPredicate(CI);
- Type *Ty = CI->getOperand(0)->getType();
- if (!Ty->isIntegerTy())
- return false;
+ const Value *LHS = CI->getOperand(0);
+ const Value *RHS = CI->getOperand(1);
+
+ Type *Ty = LHS->getType();
+ if (!Ty->isIntegerTy())
+ return false;
unsigned BW = cast<IntegerType>(Ty)->getBitWidth();
if (BW != 1 && BW != 8 && BW != 16 && BW != 32 && BW != 64)
return false;
- if (const auto *C = dyn_cast<ConstantInt>(CI->getOperand(0)))
- if (C->isNullValue())
- return true;
+ MachineBasicBlock *TBB = FuncInfo.MBBMap[BI->getSuccessor(0)];
+ MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)];
- if (const auto *C = dyn_cast<ConstantInt>(CI->getOperand(1)))
- if (C->isNullValue())
- return true;
+ // Try to take advantage of fallthrough opportunities.
+ if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
+ std::swap(TBB, FBB);
+ Predicate = CmpInst::getInversePredicate(Predicate);
+ }
- return false;
+ int TestBit = -1;
+ bool IsCmpNE;
+ if ((Predicate == CmpInst::ICMP_EQ) || (Predicate == CmpInst::ICMP_NE)) {
+ if (const auto *C = dyn_cast<ConstantInt>(LHS))
+ if (C->isNullValue())
+ std::swap(LHS, RHS);
+
+ if (!isa<ConstantInt>(RHS))
+ return false;
+
+ if (!cast<ConstantInt>(RHS)->isNullValue())
+ return false;
+
+ if (const auto *AI = dyn_cast<BinaryOperator>(LHS))
+ if (AI->getOpcode() == Instruction::And) {
+ const Value *AndLHS = AI->getOperand(0);
+ const Value *AndRHS = AI->getOperand(1);
+
+ if (const auto *C = dyn_cast<ConstantInt>(AndLHS))
+ if (C->getValue().isPowerOf2())
+ std::swap(AndLHS, AndRHS);
+
+ if (const auto *C = dyn_cast<ConstantInt>(AndRHS))
+ if (C->getValue().isPowerOf2()) {
+ TestBit = C->getValue().logBase2();
+ LHS = AndLHS;
+ }
+ }
+ IsCmpNE = Predicate == CmpInst::ICMP_NE;
+ } else if (Predicate == CmpInst::ICMP_SLT) {
+ if (!isa<ConstantInt>(RHS))
+ return false;
+
+ if (!cast<ConstantInt>(RHS)->isNullValue())
+ return false;
+
+ TestBit = BW - 1;
+ IsCmpNE = true;
+ } else if (Predicate == CmpInst::ICMP_SGT) {
+ if (!isa<ConstantInt>(RHS))
+ return false;
+
+ if (cast<ConstantInt>(RHS)->getValue() != -1)
+ return false;
+
+ TestBit = BW - 1;
+ IsCmpNE = false;
+ } else
+ return false;
+
+ static const unsigned OpcTable[2][2][2] = {
+ { {AArch64::CBZW, AArch64::CBZX },
+ {AArch64::CBNZW, AArch64::CBNZX} },
+ { {AArch64::TBZW, AArch64::TBZX },
+ {AArch64::TBNZW, AArch64::TBNZX} }
+ };
+
+ bool IsBitTest = TestBit != -1;
+ bool Is64Bit = BW == 64;
+ if (TestBit < 32 && TestBit >= 0)
+ Is64Bit = false;
+
+ unsigned Opc = OpcTable[IsBitTest][IsCmpNE][Is64Bit];
+ const MCInstrDesc &II = TII.get(Opc);
+
+ unsigned SrcReg = getRegForValue(LHS);
+ if (!SrcReg)
+ return false;
+ bool SrcIsKill = hasTrivialKill(LHS);
+
+ if (BW == 64 && !Is64Bit)
+ SrcReg = fastEmitInst_extractsubreg(MVT::i32, SrcReg, SrcIsKill,
+ AArch64::sub_32);
+
+ if ((BW < 32) && !IsBitTest) {
+ EVT CmpEVT = TLI.getValueType(Ty, true);
+ SrcReg =
+ emitIntExt(CmpEVT.getSimpleVT(), SrcReg, MVT::i32, /*isZExt*/ true);
+ }
+
+ // Emit the combined compare and branch instruction.
+ SrcReg = constrainOperandRegClass(II, SrcReg, II.getNumDefs());
+ MachineInstrBuilder MIB =
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc))
+ .addReg(SrcReg, getKillRegState(SrcIsKill));
+ if (IsBitTest)
+ MIB.addImm(TestBit);
+ MIB.addMBB(TBB);
+
+ // Obtain the branch weight and add the TrueBB to the successor list.
+ uint32_t BranchWeight = 0;
+ if (FuncInfo.BPI)
+ BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
+ TBB->getBasicBlock());
+ FuncInfo.MBB->addSuccessor(TBB, BranchWeight);
+ fastEmitBranch(FBB, DbgLoc);
+
+ return true;
}
bool AArch64FastISel::selectBranch(const Instruction *I) {
return true;
}
+ // Try to emit a combined compare-and-branch first.
+ if (emitCompareAndBranch(BI))
+ return true;
+
// Try to take advantage of fallthrough opportunities.
if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
std::swap(TBB, FBB);
Predicate = CmpInst::getInversePredicate(Predicate);
}
- // Try to optimize comparisons against zero.
- if (canFoldZeroIntoBranch(CI)) {
- const Value *LHS = CI->getOperand(0);
- const Value *RHS = CI->getOperand(1);
-
- // Canonicalize zero values to the RHS.
- if (const auto *C = dyn_cast<ConstantInt>(LHS))
- if (C->isNullValue())
- std::swap(LHS, RHS);
-
- static const unsigned OpcTable[2][2] = {
- {AArch64::CBZW, AArch64::CBZX }, {AArch64::CBNZW, AArch64::CBNZX}
- };
- bool IsCmpNE = Predicate == CmpInst::ICMP_NE;
- bool Is64Bit = LHS->getType()->isIntegerTy(64);
- unsigned Opc = OpcTable[IsCmpNE][Is64Bit];
-
- unsigned SrcReg = getRegForValue(LHS);
- if (!SrcReg)
- return false;
- bool SrcIsKill = hasTrivialKill(LHS);
-
- // Emit the combined compare and branch instruction.
- BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc))
- .addReg(SrcReg, getKillRegState(SrcIsKill))
- .addMBB(TBB);
-
- // Obtain the branch weight and add the TrueBB to the successor list.
- uint32_t BranchWeight = 0;
- if (FuncInfo.BPI)
- BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
- TBB->getBasicBlock());
- FuncInfo.MBB->addSuccessor(TBB, BranchWeight);
-
- fastEmitBranch(FBB, DbgLoc);
- return true;
- }
-
// Emit the cmp.
if (!emitCmp(CI->getOperand(0), CI->getOperand(1), CI->isUnsigned()))
return false;
}
}
- bool RV;
- unsigned ResultReg;
- RV = emitLoad(VT, ResultReg, Src);
- if (!RV)
+ unsigned ResultReg = emitLoad(VT, VT, Src);
+ if (!ResultReg)
return false;
- RV = emitStore(VT, ResultReg, Dest);
- if (!RV)
+ if (!emitStore(VT, ResultReg, Dest))
return false;
int64_t Size = VT.getSizeInBits() / 8;
ResultReg2 = fastEmitInst_rri(AArch64::CSINCWr, &AArch64::GPR32RegClass,
AArch64::WZR, /*IsKill=*/true, AArch64::WZR,
/*IsKill=*/true, getInvertedCondCode(CC));
+ (void)ResultReg2;
assert((ResultReg1 + 1) == ResultReg2 &&
"Nonconsecutive result registers.");
updateValueMap(II, ResultReg1, 2);
return fastEmitInst_rii(Opc, RC, SrcReg, /*TODO:IsKill=*/false, 0, Imm);
}
+static bool isZExtLoad(const MachineInstr *LI) {
+ switch (LI->getOpcode()) {
+ default:
+ return false;
+ case AArch64::LDURBBi:
+ case AArch64::LDURHHi:
+ case AArch64::LDURWi:
+ case AArch64::LDRBBui:
+ case AArch64::LDRHHui:
+ case AArch64::LDRWui:
+ case AArch64::LDRBBroX:
+ case AArch64::LDRHHroX:
+ case AArch64::LDRWroX:
+ case AArch64::LDRBBroW:
+ case AArch64::LDRHHroW:
+ case AArch64::LDRWroW:
+ return true;
+ }
+}
+
+static bool isSExtLoad(const MachineInstr *LI) {
+ switch (LI->getOpcode()) {
+ default:
+ return false;
+ case AArch64::LDURSBWi:
+ case AArch64::LDURSHWi:
+ case AArch64::LDURSBXi:
+ case AArch64::LDURSHXi:
+ case AArch64::LDURSWi:
+ case AArch64::LDRSBWui:
+ case AArch64::LDRSHWui:
+ case AArch64::LDRSBXui:
+ case AArch64::LDRSHXui:
+ case AArch64::LDRSWui:
+ case AArch64::LDRSBWroX:
+ case AArch64::LDRSHWroX:
+ case AArch64::LDRSBXroX:
+ case AArch64::LDRSHXroX:
+ case AArch64::LDRSWroX:
+ case AArch64::LDRSBWroW:
+ case AArch64::LDRSHWroW:
+ case AArch64::LDRSBXroW:
+ case AArch64::LDRSHXroW:
+ case AArch64::LDRSWroW:
+ return true;
+ }
+}
+
+bool AArch64FastISel::optimizeIntExtLoad(const Instruction *I, MVT RetVT,
+ MVT SrcVT) {
+ const auto *LI = dyn_cast<LoadInst>(I->getOperand(0));
+ if (!LI || !LI->hasOneUse())
+ return false;
+
+ // Check if the load instruction has already been selected.
+ unsigned Reg = lookUpRegForValue(LI);
+ if (!Reg)
+ return false;
+
+ MachineInstr *MI = MRI.getUniqueVRegDef(Reg);
+ if (!MI)
+ return false;
+
+ // Check if the correct load instruction has been emitted - SelectionDAG might
+ // have emitted a zero-extending load, but we need a sign-extending load.
+ bool IsZExt = isa<ZExtInst>(I);
+ const auto *LoadMI = MI;
+ if (LoadMI->getOpcode() == TargetOpcode::COPY &&
+ LoadMI->getOperand(1).getSubReg() == AArch64::sub_32) {
+ unsigned LoadReg = MI->getOperand(1).getReg();
+ LoadMI = MRI.getUniqueVRegDef(LoadReg);
+ assert(LoadMI && "Expected valid instruction");
+ }
+ if (!(IsZExt && isZExtLoad(LoadMI)) && !(!IsZExt && isSExtLoad(LoadMI)))
+ return false;
+
+ // Nothing to be done.
+ if (RetVT != MVT::i64 || SrcVT > MVT::i32) {
+ updateValueMap(I, Reg);
+ return true;
+ }
+
+ if (IsZExt) {
+ unsigned Reg64 = createResultReg(&AArch64::GPR64RegClass);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
+ TII.get(AArch64::SUBREG_TO_REG), Reg64)
+ .addImm(0)
+ .addReg(Reg, getKillRegState(true))
+ .addImm(AArch64::sub_32);
+ Reg = Reg64;
+ } else {
+ assert((MI->getOpcode() == TargetOpcode::COPY &&
+ MI->getOperand(1).getSubReg() == AArch64::sub_32) &&
+ "Expected copy instruction");
+ Reg = MI->getOperand(1).getReg();
+ MI->eraseFromParent();
+ }
+ updateValueMap(I, Reg);
+ return true;
+}
+
bool AArch64FastISel::selectIntExt(const Instruction *I) {
assert((isa<ZExtInst>(I) || isa<SExtInst>(I)) &&
"Unexpected integer extend instruction.");
if (!isTypeSupported(I->getOperand(0)->getType(), SrcVT))
return false;
- if (isIntExtFree(I)) {
- unsigned SrcReg = getRegForValue(I->getOperand(0));
- if (!SrcReg)
- return false;
- bool SrcIsKill = hasTrivialKill(I->getOperand(0));
-
- const TargetRegisterClass *RC = (RetVT == MVT::i64) ?
- &AArch64::GPR64RegClass : &AArch64::GPR32RegClass;
- unsigned ResultReg = createResultReg(RC);
- if (RetVT == MVT::i64 && SrcVT != MVT::i64) {
- BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
- TII.get(AArch64::SUBREG_TO_REG), ResultReg)
- .addImm(0)
- .addReg(SrcReg, getKillRegState(SrcIsKill))
- .addImm(AArch64::sub_32);
- } else {
- BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
- TII.get(TargetOpcode::COPY), ResultReg)
- .addReg(SrcReg, getKillRegState(SrcIsKill));
- }
- updateValueMap(I, ResultReg);
+ // Try to optimize already sign-/zero-extended values from load instructions.
+ if (optimizeIntExtLoad(I, RetVT, SrcVT))
return true;
- }
unsigned SrcReg = getRegForValue(I->getOperand(0));
if (!SrcReg)
return false;
- bool SrcRegIsKill = hasTrivialKill(I->getOperand(0));
+ bool SrcIsKill = hasTrivialKill(I->getOperand(0));
- unsigned ResultReg = 0;
- if (isIntExtFree(I)) {
- if (RetVT == MVT::i64) {
- ResultReg = createResultReg(&AArch64::GPR64RegClass);
- BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
- TII.get(AArch64::SUBREG_TO_REG), ResultReg)
- .addImm(0)
- .addReg(SrcReg, getKillRegState(SrcRegIsKill))
- .addImm(AArch64::sub_32);
- } else
- ResultReg = SrcReg;
+ // Try to optimize already sign-/zero-extended values from function arguments.
+ bool IsZExt = isa<ZExtInst>(I);
+ if (const auto *Arg = dyn_cast<Argument>(I->getOperand(0))) {
+ if ((IsZExt && Arg->hasZExtAttr()) || (!IsZExt && Arg->hasSExtAttr())) {
+ if (RetVT == MVT::i64 && SrcVT != MVT::i64) {
+ unsigned ResultReg = createResultReg(&AArch64::GPR64RegClass);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
+ TII.get(AArch64::SUBREG_TO_REG), ResultReg)
+ .addImm(0)
+ .addReg(SrcReg, getKillRegState(SrcIsKill))
+ .addImm(AArch64::sub_32);
+ SrcReg = ResultReg;
+ }
+ updateValueMap(I, SrcReg);
+ return true;
+ }
}
- if (!ResultReg)
- ResultReg = emitIntExt(SrcVT, SrcReg, RetVT, isa<ZExtInst>(I));
-
+ unsigned ResultReg = emitIntExt(SrcVT, SrcReg, RetVT, IsZExt);
if (!ResultReg)
return false;
return true;
}
- unsigned Pow2MinusOne = (1 << Lg2) - 1;
- unsigned AddReg = emitAddSub_ri(/*UseAdd=*/true, VT, Src0Reg,
- /*IsKill=*/false, Pow2MinusOne);
+ int64_t Pow2MinusOne = (1ULL << Lg2) - 1;
+ unsigned AddReg = emitAdd_ri_(VT, Src0Reg, /*IsKill=*/false, Pow2MinusOne);
if (!AddReg)
return false;
return true;
}
+/// This is mostly a copy of the existing FastISel GEP code, but we have to
+/// duplicate it for AArch64, because otherwise we would bail out even for
+/// simple cases. This is because the standard fastEmit functions don't cover
+/// MUL at all and ADD is lowered very inefficientily.
+bool AArch64FastISel::selectGetElementPtr(const Instruction *I) {
+ unsigned N = getRegForValue(I->getOperand(0));
+ if (!N)
+ return false;
+ bool NIsKill = hasTrivialKill(I->getOperand(0));
+
+ // Keep a running tab of the total offset to coalesce multiple N = N + Offset
+ // into a single N = N + TotalOffset.
+ uint64_t TotalOffs = 0;
+ Type *Ty = I->getOperand(0)->getType();
+ MVT VT = TLI.getPointerTy();
+ for (auto OI = std::next(I->op_begin()), E = I->op_end(); OI != E; ++OI) {
+ const Value *Idx = *OI;
+ if (auto *StTy = dyn_cast<StructType>(Ty)) {
+ unsigned Field = cast<ConstantInt>(Idx)->getZExtValue();
+ // N = N + Offset
+ if (Field)
+ TotalOffs += DL.getStructLayout(StTy)->getElementOffset(Field);
+ Ty = StTy->getElementType(Field);
+ } else {
+ Ty = cast<SequentialType>(Ty)->getElementType();
+ // If this is a constant subscript, handle it quickly.
+ if (const auto *CI = dyn_cast<ConstantInt>(Idx)) {
+ if (CI->isZero())
+ continue;
+ // N = N + Offset
+ TotalOffs +=
+ DL.getTypeAllocSize(Ty) * cast<ConstantInt>(CI)->getSExtValue();
+ continue;
+ }
+ if (TotalOffs) {
+ N = emitAdd_ri_(VT, N, NIsKill, TotalOffs);
+ if (!N)
+ return false;
+ NIsKill = true;
+ TotalOffs = 0;
+ }
+
+ // N = N + Idx * ElementSize;
+ uint64_t ElementSize = DL.getTypeAllocSize(Ty);
+ std::pair<unsigned, bool> Pair = getRegForGEPIndex(Idx);
+ unsigned IdxN = Pair.first;
+ bool IdxNIsKill = Pair.second;
+ if (!IdxN)
+ return false;
+
+ if (ElementSize != 1) {
+ unsigned C = fastEmit_i(VT, VT, ISD::Constant, ElementSize);
+ if (!C)
+ return false;
+ IdxN = emitMul_rr(VT, IdxN, IdxNIsKill, C, true);
+ if (!IdxN)
+ return false;
+ IdxNIsKill = true;
+ }
+ N = fastEmit_rr(VT, VT, ISD::ADD, N, NIsKill, IdxN, IdxNIsKill);
+ if (!N)
+ return false;
+ }
+ }
+ if (TotalOffs) {
+ N = emitAdd_ri_(VT, N, NIsKill, TotalOffs);
+ if (!N)
+ return false;
+ }
+ updateValueMap(I, N);
+ return true;
+}
+
bool AArch64FastISel::fastSelectInstruction(const Instruction *I) {
switch (I->getOpcode()) {
default:
return selectRet(I);
case Instruction::FRem:
return selectFRem(I);
+ case Instruction::GetElementPtr:
+ return selectGetElementPtr(I);
}
// fall-back to target-independent instruction selection.
projects / oota-llvm.git / blobdiff