1 //===-- PPCISelDAGToDAG.cpp - PPC --pattern matching inst selector --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines a pattern matching instruction selector for PowerPC,
11 // converting from a legalized dag to a PPC dag.
13 //===----------------------------------------------------------------------===//
15 #define DEBUG_TYPE "ppc-codegen"
17 #include "PPCPredicates.h"
18 #include "PPCTargetMachine.h"
19 #include "PPCISelLowering.h"
20 #include "PPCHazardRecognizers.h"
21 #include "llvm/CodeGen/MachineInstrBuilder.h"
22 #include "llvm/CodeGen/MachineFunction.h"
23 #include "llvm/CodeGen/MachineRegisterInfo.h"
24 #include "llvm/CodeGen/SelectionDAG.h"
25 #include "llvm/CodeGen/SelectionDAGISel.h"
26 #include "llvm/Target/TargetOptions.h"
27 #include "llvm/Constants.h"
28 #include "llvm/Function.h"
29 #include "llvm/GlobalValue.h"
30 #include "llvm/Intrinsics.h"
31 #include "llvm/Support/Debug.h"
32 #include "llvm/Support/MathExtras.h"
33 #include "llvm/Support/Compiler.h"
34 #include "llvm/Support/ErrorHandling.h"
35 #include "llvm/Support/raw_ostream.h"
39 //===--------------------------------------------------------------------===//
40 /// PPCDAGToDAGISel - PPC specific code to select PPC machine
41 /// instructions for SelectionDAG operations.
43 class VISIBILITY_HIDDEN PPCDAGToDAGISel : public SelectionDAGISel {
45 PPCTargetLowering &PPCLowering;
46 const PPCSubtarget &PPCSubTarget;
47 unsigned GlobalBaseReg;
49 explicit PPCDAGToDAGISel(PPCTargetMachine &tm)
50 : SelectionDAGISel(tm), TM(tm),
51 PPCLowering(*TM.getTargetLowering()),
52 PPCSubTarget(*TM.getSubtargetImpl()) {}
54 virtual bool runOnFunction(Function &Fn) {
55 // Do not codegen any 'available_externally' functions at all, they have
56 // definitions outside the translation unit.
57 if (Fn.hasAvailableExternallyLinkage())
60 // Make sure we re-emit a set of the global base reg if necessary
62 SelectionDAGISel::runOnFunction(Fn);
68 /// getI32Imm - Return a target constant with the specified value, of type
70 inline SDValue getI32Imm(unsigned Imm) {
71 return CurDAG->getTargetConstant(Imm, MVT::i32);
74 /// getI64Imm - Return a target constant with the specified value, of type
76 inline SDValue getI64Imm(uint64_t Imm) {
77 return CurDAG->getTargetConstant(Imm, MVT::i64);
80 /// getSmallIPtrImm - Return a target constant of pointer type.
81 inline SDValue getSmallIPtrImm(unsigned Imm) {
82 return CurDAG->getTargetConstant(Imm, PPCLowering.getPointerTy());
85 /// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s
86 /// with any number of 0s on either side. The 1s are allowed to wrap from
87 /// LSB to MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs.
88 /// 0x0F0F0000 is not, since all 1s are not contiguous.
89 static bool isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME);
92 /// isRotateAndMask - Returns true if Mask and Shift can be folded into a
93 /// rotate and mask opcode and mask operation.
94 static bool isRotateAndMask(SDNode *N, unsigned Mask, bool IsShiftMask,
95 unsigned &SH, unsigned &MB, unsigned &ME);
97 /// getGlobalBaseReg - insert code into the entry mbb to materialize the PIC
98 /// base register. Return the virtual register that holds this value.
99 SDNode *getGlobalBaseReg();
101 // Select - Convert the specified operand from a target-independent to a
102 // target-specific node if it hasn't already been changed.
103 SDNode *Select(SDValue Op);
105 SDNode *SelectBitfieldInsert(SDNode *N);
107 /// SelectCC - Select a comparison of the specified values with the
108 /// specified condition code, returning the CR# of the expression.
109 SDValue SelectCC(SDValue LHS, SDValue RHS, ISD::CondCode CC, DebugLoc dl);
111 /// SelectAddrImm - Returns true if the address N can be represented by
112 /// a base register plus a signed 16-bit displacement [r+imm].
113 bool SelectAddrImm(SDValue Op, SDValue N, SDValue &Disp,
115 return PPCLowering.SelectAddressRegImm(N, Disp, Base, *CurDAG);
118 /// SelectAddrImmOffs - Return true if the operand is valid for a preinc
119 /// immediate field. Because preinc imms have already been validated, just
121 bool SelectAddrImmOffs(SDValue Op, SDValue N, SDValue &Out) const {
126 /// SelectAddrIdx - Given the specified addressed, check to see if it can be
127 /// represented as an indexed [r+r] operation. Returns false if it can
128 /// be represented by [r+imm], which are preferred.
129 bool SelectAddrIdx(SDValue Op, SDValue N, SDValue &Base,
131 return PPCLowering.SelectAddressRegReg(N, Base, Index, *CurDAG);
134 /// SelectAddrIdxOnly - Given the specified addressed, force it to be
135 /// represented as an indexed [r+r] operation.
136 bool SelectAddrIdxOnly(SDValue Op, SDValue N, SDValue &Base,
138 return PPCLowering.SelectAddressRegRegOnly(N, Base, Index, *CurDAG);
141 /// SelectAddrImmShift - Returns true if the address N can be represented by
142 /// a base register plus a signed 14-bit displacement [r+imm*4]. Suitable
143 /// for use by STD and friends.
144 bool SelectAddrImmShift(SDValue Op, SDValue N, SDValue &Disp,
146 return PPCLowering.SelectAddressRegImmShift(N, Disp, Base, *CurDAG);
149 /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
150 /// inline asm expressions.
151 virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op,
153 std::vector<SDValue> &OutOps) {
155 switch (ConstraintCode) {
156 default: return true;
158 if (!SelectAddrIdx(Op, Op, Op0, Op1))
159 SelectAddrImm(Op, Op, Op0, Op1);
161 case 'o': // offsetable
162 if (!SelectAddrImm(Op, Op, Op0, Op1)) {
164 Op1 = getSmallIPtrImm(0);
167 case 'v': // not offsetable
168 SelectAddrIdxOnly(Op, Op, Op0, Op1);
172 OutOps.push_back(Op0);
173 OutOps.push_back(Op1);
177 SDValue BuildSDIVSequence(SDNode *N);
178 SDValue BuildUDIVSequence(SDNode *N);
180 /// InstructionSelect - This callback is invoked by
181 /// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
182 virtual void InstructionSelect();
184 void InsertVRSaveCode(Function &Fn);
186 virtual const char *getPassName() const {
187 return "PowerPC DAG->DAG Pattern Instruction Selection";
190 /// CreateTargetHazardRecognizer - Return the hazard recognizer to use for
191 /// this target when scheduling the DAG.
192 virtual ScheduleHazardRecognizer *CreateTargetHazardRecognizer() {
193 // Should use subtarget info to pick the right hazard recognizer. For
194 // now, always return a PPC970 recognizer.
195 const TargetInstrInfo *II = TM.getInstrInfo();
196 assert(II && "No InstrInfo?");
197 return new PPCHazardRecognizer970(*II);
200 // Include the pieces autogenerated from the target description.
201 #include "PPCGenDAGISel.inc"
204 SDNode *SelectSETCC(SDValue Op);
208 /// InstructionSelect - This callback is invoked by
209 /// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
210 void PPCDAGToDAGISel::InstructionSelect() {
213 // Select target instructions for the DAG.
215 CurDAG->RemoveDeadNodes();
218 /// InsertVRSaveCode - Once the entire function has been instruction selected,
219 /// all virtual registers are created and all machine instructions are built,
220 /// check to see if we need to save/restore VRSAVE. If so, do it.
221 void PPCDAGToDAGISel::InsertVRSaveCode(Function &F) {
222 // Check to see if this function uses vector registers, which means we have to
223 // save and restore the VRSAVE register and update it with the regs we use.
225 // In this case, there will be virtual registers of vector type type created
226 // by the scheduler. Detect them now.
227 MachineFunction &Fn = MachineFunction::get(&F);
228 bool HasVectorVReg = false;
229 for (unsigned i = TargetRegisterInfo::FirstVirtualRegister,
230 e = RegInfo->getLastVirtReg()+1; i != e; ++i)
231 if (RegInfo->getRegClass(i) == &PPC::VRRCRegClass) {
232 HasVectorVReg = true;
235 if (!HasVectorVReg) return; // nothing to do.
237 // If we have a vector register, we want to emit code into the entry and exit
238 // blocks to save and restore the VRSAVE register. We do this here (instead
239 // of marking all vector instructions as clobbering VRSAVE) for two reasons:
241 // 1. This (trivially) reduces the load on the register allocator, by not
242 // having to represent the live range of the VRSAVE register.
243 // 2. This (more significantly) allows us to create a temporary virtual
244 // register to hold the saved VRSAVE value, allowing this temporary to be
245 // register allocated, instead of forcing it to be spilled to the stack.
247 // Create two vregs - one to hold the VRSAVE register that is live-in to the
248 // function and one for the value after having bits or'd into it.
249 unsigned InVRSAVE = RegInfo->createVirtualRegister(&PPC::GPRCRegClass);
250 unsigned UpdatedVRSAVE = RegInfo->createVirtualRegister(&PPC::GPRCRegClass);
252 const TargetInstrInfo &TII = *TM.getInstrInfo();
253 MachineBasicBlock &EntryBB = *Fn.begin();
254 DebugLoc dl = DebugLoc::getUnknownLoc();
255 // Emit the following code into the entry block:
256 // InVRSAVE = MFVRSAVE
257 // UpdatedVRSAVE = UPDATE_VRSAVE InVRSAVE
258 // MTVRSAVE UpdatedVRSAVE
259 MachineBasicBlock::iterator IP = EntryBB.begin(); // Insert Point
260 BuildMI(EntryBB, IP, dl, TII.get(PPC::MFVRSAVE), InVRSAVE);
261 BuildMI(EntryBB, IP, dl, TII.get(PPC::UPDATE_VRSAVE),
262 UpdatedVRSAVE).addReg(InVRSAVE);
263 BuildMI(EntryBB, IP, dl, TII.get(PPC::MTVRSAVE)).addReg(UpdatedVRSAVE);
265 // Find all return blocks, outputting a restore in each epilog.
266 for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) {
267 if (!BB->empty() && BB->back().getDesc().isReturn()) {
268 IP = BB->end(); --IP;
270 // Skip over all terminator instructions, which are part of the return
272 MachineBasicBlock::iterator I2 = IP;
273 while (I2 != BB->begin() && (--I2)->getDesc().isTerminator())
276 // Emit: MTVRSAVE InVRSave
277 BuildMI(*BB, IP, dl, TII.get(PPC::MTVRSAVE)).addReg(InVRSAVE);
283 /// getGlobalBaseReg - Output the instructions required to put the
284 /// base address to use for accessing globals into a register.
286 SDNode *PPCDAGToDAGISel::getGlobalBaseReg() {
287 if (!GlobalBaseReg) {
288 const TargetInstrInfo &TII = *TM.getInstrInfo();
289 // Insert the set of GlobalBaseReg into the first MBB of the function
290 MachineBasicBlock &FirstMBB = BB->getParent()->front();
291 MachineBasicBlock::iterator MBBI = FirstMBB.begin();
292 DebugLoc dl = DebugLoc::getUnknownLoc();
294 if (PPCLowering.getPointerTy() == MVT::i32) {
295 GlobalBaseReg = RegInfo->createVirtualRegister(PPC::GPRCRegisterClass);
296 BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR), PPC::LR);
297 BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR), GlobalBaseReg);
299 GlobalBaseReg = RegInfo->createVirtualRegister(PPC::G8RCRegisterClass);
300 BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR8), PPC::LR8);
301 BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR8), GlobalBaseReg);
304 return CurDAG->getRegister(GlobalBaseReg,
305 PPCLowering.getPointerTy()).getNode();
308 /// isIntS16Immediate - This method tests to see if the node is either a 32-bit
309 /// or 64-bit immediate, and if the value can be accurately represented as a
310 /// sign extension from a 16-bit value. If so, this returns true and the
312 static bool isIntS16Immediate(SDNode *N, short &Imm) {
313 if (N->getOpcode() != ISD::Constant)
316 Imm = (short)cast<ConstantSDNode>(N)->getZExtValue();
317 if (N->getValueType(0) == MVT::i32)
318 return Imm == (int32_t)cast<ConstantSDNode>(N)->getZExtValue();
320 return Imm == (int64_t)cast<ConstantSDNode>(N)->getZExtValue();
323 static bool isIntS16Immediate(SDValue Op, short &Imm) {
324 return isIntS16Immediate(Op.getNode(), Imm);
328 /// isInt32Immediate - This method tests to see if the node is a 32-bit constant
329 /// operand. If so Imm will receive the 32-bit value.
330 static bool isInt32Immediate(SDNode *N, unsigned &Imm) {
331 if (N->getOpcode() == ISD::Constant && N->getValueType(0) == MVT::i32) {
332 Imm = cast<ConstantSDNode>(N)->getZExtValue();
338 /// isInt64Immediate - This method tests to see if the node is a 64-bit constant
339 /// operand. If so Imm will receive the 64-bit value.
340 static bool isInt64Immediate(SDNode *N, uint64_t &Imm) {
341 if (N->getOpcode() == ISD::Constant && N->getValueType(0) == MVT::i64) {
342 Imm = cast<ConstantSDNode>(N)->getZExtValue();
348 // isInt32Immediate - This method tests to see if a constant operand.
349 // If so Imm will receive the 32 bit value.
350 static bool isInt32Immediate(SDValue N, unsigned &Imm) {
351 return isInt32Immediate(N.getNode(), Imm);
355 // isOpcWithIntImmediate - This method tests to see if the node is a specific
356 // opcode and that it has a immediate integer right operand.
357 // If so Imm will receive the 32 bit value.
358 static bool isOpcWithIntImmediate(SDNode *N, unsigned Opc, unsigned& Imm) {
359 return N->getOpcode() == Opc
360 && isInt32Immediate(N->getOperand(1).getNode(), Imm);
363 bool PPCDAGToDAGISel::isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME) {
364 if (isShiftedMask_32(Val)) {
365 // look for the first non-zero bit
366 MB = CountLeadingZeros_32(Val);
367 // look for the first zero bit after the run of ones
368 ME = CountLeadingZeros_32((Val - 1) ^ Val);
371 Val = ~Val; // invert mask
372 if (isShiftedMask_32(Val)) {
373 // effectively look for the first zero bit
374 ME = CountLeadingZeros_32(Val) - 1;
375 // effectively look for the first one bit after the run of zeros
376 MB = CountLeadingZeros_32((Val - 1) ^ Val) + 1;
384 bool PPCDAGToDAGISel::isRotateAndMask(SDNode *N, unsigned Mask,
385 bool IsShiftMask, unsigned &SH,
386 unsigned &MB, unsigned &ME) {
387 // Don't even go down this path for i64, since different logic will be
388 // necessary for rldicl/rldicr/rldimi.
389 if (N->getValueType(0) != MVT::i32)
393 unsigned Indeterminant = ~0; // bit mask marking indeterminant results
394 unsigned Opcode = N->getOpcode();
395 if (N->getNumOperands() != 2 ||
396 !isInt32Immediate(N->getOperand(1).getNode(), Shift) || (Shift > 31))
399 if (Opcode == ISD::SHL) {
400 // apply shift left to mask if it comes first
401 if (IsShiftMask) Mask = Mask << Shift;
402 // determine which bits are made indeterminant by shift
403 Indeterminant = ~(0xFFFFFFFFu << Shift);
404 } else if (Opcode == ISD::SRL) {
405 // apply shift right to mask if it comes first
406 if (IsShiftMask) Mask = Mask >> Shift;
407 // determine which bits are made indeterminant by shift
408 Indeterminant = ~(0xFFFFFFFFu >> Shift);
409 // adjust for the left rotate
411 } else if (Opcode == ISD::ROTL) {
417 // if the mask doesn't intersect any Indeterminant bits
418 if (Mask && !(Mask & Indeterminant)) {
420 // make sure the mask is still a mask (wrap arounds may not be)
421 return isRunOfOnes(Mask, MB, ME);
426 /// SelectBitfieldInsert - turn an or of two masked values into
427 /// the rotate left word immediate then mask insert (rlwimi) instruction.
428 SDNode *PPCDAGToDAGISel::SelectBitfieldInsert(SDNode *N) {
429 SDValue Op0 = N->getOperand(0);
430 SDValue Op1 = N->getOperand(1);
431 DebugLoc dl = N->getDebugLoc();
433 APInt LKZ, LKO, RKZ, RKO;
434 CurDAG->ComputeMaskedBits(Op0, APInt::getAllOnesValue(32), LKZ, LKO);
435 CurDAG->ComputeMaskedBits(Op1, APInt::getAllOnesValue(32), RKZ, RKO);
437 unsigned TargetMask = LKZ.getZExtValue();
438 unsigned InsertMask = RKZ.getZExtValue();
440 if ((TargetMask | InsertMask) == 0xFFFFFFFF) {
441 unsigned Op0Opc = Op0.getOpcode();
442 unsigned Op1Opc = Op1.getOpcode();
443 unsigned Value, SH = 0;
444 TargetMask = ~TargetMask;
445 InsertMask = ~InsertMask;
447 // If the LHS has a foldable shift and the RHS does not, then swap it to the
448 // RHS so that we can fold the shift into the insert.
449 if (Op0Opc == ISD::AND && Op1Opc == ISD::AND) {
450 if (Op0.getOperand(0).getOpcode() == ISD::SHL ||
451 Op0.getOperand(0).getOpcode() == ISD::SRL) {
452 if (Op1.getOperand(0).getOpcode() != ISD::SHL &&
453 Op1.getOperand(0).getOpcode() != ISD::SRL) {
455 std::swap(Op0Opc, Op1Opc);
456 std::swap(TargetMask, InsertMask);
459 } else if (Op0Opc == ISD::SHL || Op0Opc == ISD::SRL) {
460 if (Op1Opc == ISD::AND && Op1.getOperand(0).getOpcode() != ISD::SHL &&
461 Op1.getOperand(0).getOpcode() != ISD::SRL) {
463 std::swap(Op0Opc, Op1Opc);
464 std::swap(TargetMask, InsertMask);
469 if (InsertMask && isRunOfOnes(InsertMask, MB, ME)) {
470 SDValue Tmp1, Tmp2, Tmp3;
471 bool DisjointMask = (TargetMask ^ InsertMask) == 0xFFFFFFFF;
473 if ((Op1Opc == ISD::SHL || Op1Opc == ISD::SRL) &&
474 isInt32Immediate(Op1.getOperand(1), Value)) {
475 Op1 = Op1.getOperand(0);
476 SH = (Op1Opc == ISD::SHL) ? Value : 32 - Value;
478 if (Op1Opc == ISD::AND) {
479 unsigned SHOpc = Op1.getOperand(0).getOpcode();
480 if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) &&
481 isInt32Immediate(Op1.getOperand(0).getOperand(1), Value)) {
482 Op1 = Op1.getOperand(0).getOperand(0);
483 SH = (SHOpc == ISD::SHL) ? Value : 32 - Value;
485 Op1 = Op1.getOperand(0);
489 Tmp3 = (Op0Opc == ISD::AND && DisjointMask) ? Op0.getOperand(0) : Op0;
491 SDValue Ops[] = { Tmp3, Op1, getI32Imm(SH), getI32Imm(MB),
493 return CurDAG->getTargetNode(PPC::RLWIMI, dl, MVT::i32, Ops, 5);
499 /// SelectCC - Select a comparison of the specified values with the specified
500 /// condition code, returning the CR# of the expression.
501 SDValue PPCDAGToDAGISel::SelectCC(SDValue LHS, SDValue RHS,
502 ISD::CondCode CC, DebugLoc dl) {
503 // Always select the LHS.
506 if (LHS.getValueType() == MVT::i32) {
508 if (CC == ISD::SETEQ || CC == ISD::SETNE) {
509 if (isInt32Immediate(RHS, Imm)) {
510 // SETEQ/SETNE comparison with 16-bit immediate, fold it.
512 return SDValue(CurDAG->getTargetNode(PPC::CMPLWI, dl, MVT::i32, LHS,
513 getI32Imm(Imm & 0xFFFF)), 0);
514 // If this is a 16-bit signed immediate, fold it.
515 if (isInt16((int)Imm))
516 return SDValue(CurDAG->getTargetNode(PPC::CMPWI, dl, MVT::i32, LHS,
517 getI32Imm(Imm & 0xFFFF)), 0);
519 // For non-equality comparisons, the default code would materialize the
520 // constant, then compare against it, like this:
524 // Since we are just comparing for equality, we can emit this instead:
525 // xoris r0,r3,0x1234
526 // cmplwi cr0,r0,0x5678
528 SDValue Xor(CurDAG->getTargetNode(PPC::XORIS, dl, MVT::i32, LHS,
529 getI32Imm(Imm >> 16)), 0);
530 return SDValue(CurDAG->getTargetNode(PPC::CMPLWI, dl, MVT::i32, Xor,
531 getI32Imm(Imm & 0xFFFF)), 0);
534 } else if (ISD::isUnsignedIntSetCC(CC)) {
535 if (isInt32Immediate(RHS, Imm) && isUInt16(Imm))
536 return SDValue(CurDAG->getTargetNode(PPC::CMPLWI, dl, MVT::i32, LHS,
537 getI32Imm(Imm & 0xFFFF)), 0);
541 if (isIntS16Immediate(RHS, SImm))
542 return SDValue(CurDAG->getTargetNode(PPC::CMPWI, dl, MVT::i32, LHS,
543 getI32Imm((int)SImm & 0xFFFF)),
547 } else if (LHS.getValueType() == MVT::i64) {
549 if (CC == ISD::SETEQ || CC == ISD::SETNE) {
550 if (isInt64Immediate(RHS.getNode(), Imm)) {
551 // SETEQ/SETNE comparison with 16-bit immediate, fold it.
553 return SDValue(CurDAG->getTargetNode(PPC::CMPLDI, dl, MVT::i64, LHS,
554 getI32Imm(Imm & 0xFFFF)), 0);
555 // If this is a 16-bit signed immediate, fold it.
557 return SDValue(CurDAG->getTargetNode(PPC::CMPDI, dl, MVT::i64, LHS,
558 getI32Imm(Imm & 0xFFFF)), 0);
560 // For non-equality comparisons, the default code would materialize the
561 // constant, then compare against it, like this:
565 // Since we are just comparing for equality, we can emit this instead:
566 // xoris r0,r3,0x1234
567 // cmpldi cr0,r0,0x5678
570 SDValue Xor(CurDAG->getTargetNode(PPC::XORIS8, dl, MVT::i64, LHS,
571 getI64Imm(Imm >> 16)), 0);
572 return SDValue(CurDAG->getTargetNode(PPC::CMPLDI, dl, MVT::i64, Xor,
573 getI64Imm(Imm & 0xFFFF)), 0);
577 } else if (ISD::isUnsignedIntSetCC(CC)) {
578 if (isInt64Immediate(RHS.getNode(), Imm) && isUInt16(Imm))
579 return SDValue(CurDAG->getTargetNode(PPC::CMPLDI, dl, MVT::i64, LHS,
580 getI64Imm(Imm & 0xFFFF)), 0);
584 if (isIntS16Immediate(RHS, SImm))
585 return SDValue(CurDAG->getTargetNode(PPC::CMPDI, dl, MVT::i64, LHS,
586 getI64Imm(SImm & 0xFFFF)),
590 } else if (LHS.getValueType() == MVT::f32) {
593 assert(LHS.getValueType() == MVT::f64 && "Unknown vt!");
596 return SDValue(CurDAG->getTargetNode(Opc, dl, MVT::i32, LHS, RHS), 0);
599 static PPC::Predicate getPredicateForSetCC(ISD::CondCode CC) {
605 LLVM_UNREACHABLE("Should be lowered by legalize!");
606 default: LLVM_UNREACHABLE("Unknown condition!");
608 case ISD::SETEQ: return PPC::PRED_EQ;
610 case ISD::SETNE: return PPC::PRED_NE;
612 case ISD::SETLT: return PPC::PRED_LT;
614 case ISD::SETLE: return PPC::PRED_LE;
616 case ISD::SETGT: return PPC::PRED_GT;
618 case ISD::SETGE: return PPC::PRED_GE;
619 case ISD::SETO: return PPC::PRED_NU;
620 case ISD::SETUO: return PPC::PRED_UN;
621 // These two are invalid for floating point. Assume we have int.
622 case ISD::SETULT: return PPC::PRED_LT;
623 case ISD::SETUGT: return PPC::PRED_GT;
627 /// getCRIdxForSetCC - Return the index of the condition register field
628 /// associated with the SetCC condition, and whether or not the field is
629 /// treated as inverted. That is, lt = 0; ge = 0 inverted.
631 /// If this returns with Other != -1, then the returned comparison is an or of
632 /// two simpler comparisons. In this case, Invert is guaranteed to be false.
633 static unsigned getCRIdxForSetCC(ISD::CondCode CC, bool &Invert, int &Other) {
637 default: LLVM_UNREACHABLE("Unknown condition!");
639 case ISD::SETLT: return 0; // Bit #0 = SETOLT
641 case ISD::SETGT: return 1; // Bit #1 = SETOGT
643 case ISD::SETEQ: return 2; // Bit #2 = SETOEQ
644 case ISD::SETUO: return 3; // Bit #3 = SETUO
646 case ISD::SETGE: Invert = true; return 0; // !Bit #0 = SETUGE
648 case ISD::SETLE: Invert = true; return 1; // !Bit #1 = SETULE
650 case ISD::SETNE: Invert = true; return 2; // !Bit #2 = SETUNE
651 case ISD::SETO: Invert = true; return 3; // !Bit #3 = SETO
656 LLVM_UNREACHABLE("Invalid branch code: should be expanded by legalize");
657 // These are invalid for floating point. Assume integer.
658 case ISD::SETULT: return 0;
659 case ISD::SETUGT: return 1;
664 SDNode *PPCDAGToDAGISel::SelectSETCC(SDValue Op) {
665 SDNode *N = Op.getNode();
666 DebugLoc dl = N->getDebugLoc();
668 ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(2))->get();
669 if (isInt32Immediate(N->getOperand(1), Imm)) {
670 // We can codegen setcc op, imm very efficiently compared to a brcond.
671 // Check for those cases here.
674 SDValue Op = N->getOperand(0);
678 Op = SDValue(CurDAG->getTargetNode(PPC::CNTLZW, dl, MVT::i32, Op), 0);
679 SDValue Ops[] = { Op, getI32Imm(27), getI32Imm(5), getI32Imm(31) };
680 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
684 SDValue(CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag,
685 Op, getI32Imm(~0U)), 0);
686 return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, AD, Op,
690 SDValue Ops[] = { Op, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
691 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
695 SDValue(CurDAG->getTargetNode(PPC::NEG, dl, MVT::i32, Op), 0);
696 T = SDValue(CurDAG->getTargetNode(PPC::ANDC, dl, MVT::i32, T, Op), 0);
697 SDValue Ops[] = { T, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
698 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
701 } else if (Imm == ~0U) { // setcc op, -1
702 SDValue Op = N->getOperand(0);
706 Op = SDValue(CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag,
707 Op, getI32Imm(1)), 0);
708 return CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32,
709 SDValue(CurDAG->getTargetNode(PPC::LI, dl,
714 Op = SDValue(CurDAG->getTargetNode(PPC::NOR, dl, MVT::i32, Op, Op), 0);
715 SDNode *AD = CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag,
717 return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, SDValue(AD, 0),
721 SDValue AD = SDValue(CurDAG->getTargetNode(PPC::ADDI, dl, MVT::i32, Op,
723 SDValue AN = SDValue(CurDAG->getTargetNode(PPC::AND, dl, MVT::i32, AD,
725 SDValue Ops[] = { AN, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
726 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
729 SDValue Ops[] = { Op, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
730 Op = SDValue(CurDAG->getTargetNode(PPC::RLWINM, dl, MVT::i32, Ops, 4),
732 return CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Op,
741 unsigned Idx = getCRIdxForSetCC(CC, Inv, OtherCondIdx);
742 SDValue CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC, dl);
745 // Force the ccreg into CR7.
746 SDValue CR7Reg = CurDAG->getRegister(PPC::CR7, MVT::i32);
748 SDValue InFlag(0, 0); // Null incoming flag value.
749 CCReg = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, CR7Reg, CCReg,
752 if (PPCSubTarget.isGigaProcessor() && OtherCondIdx == -1)
753 IntCR = SDValue(CurDAG->getTargetNode(PPC::MFOCRF, dl, MVT::i32, CR7Reg,
756 IntCR = SDValue(CurDAG->getTargetNode(PPC::MFCR, dl, MVT::i32, CCReg), 0);
758 SDValue Ops[] = { IntCR, getI32Imm((32-(3-Idx)) & 31),
759 getI32Imm(31), getI32Imm(31) };
760 if (OtherCondIdx == -1 && !Inv)
761 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
763 // Get the specified bit.
765 SDValue(CurDAG->getTargetNode(PPC::RLWINM, dl, MVT::i32, Ops, 4), 0);
767 assert(OtherCondIdx == -1 && "Can't have split plus negation");
768 return CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Tmp, getI32Imm(1));
771 // Otherwise, we have to turn an operation like SETONE -> SETOLT | SETOGT.
772 // We already got the bit for the first part of the comparison (e.g. SETULE).
774 // Get the other bit of the comparison.
775 Ops[1] = getI32Imm((32-(3-OtherCondIdx)) & 31);
777 SDValue(CurDAG->getTargetNode(PPC::RLWINM, dl, MVT::i32, Ops, 4), 0);
779 return CurDAG->SelectNodeTo(N, PPC::OR, MVT::i32, Tmp, OtherCond);
783 // Select - Convert the specified operand from a target-independent to a
784 // target-specific node if it hasn't already been changed.
785 SDNode *PPCDAGToDAGISel::Select(SDValue Op) {
786 SDNode *N = Op.getNode();
787 DebugLoc dl = Op.getDebugLoc();
788 if (N->isMachineOpcode())
789 return NULL; // Already selected.
791 switch (N->getOpcode()) {
794 case ISD::Constant: {
795 if (N->getValueType(0) == MVT::i64) {
797 int64_t Imm = cast<ConstantSDNode>(N)->getZExtValue();
798 // Assume no remaining bits.
799 unsigned Remainder = 0;
800 // Assume no shift required.
803 // If it can't be represented as a 32 bit value.
805 Shift = CountTrailingZeros_64(Imm);
806 int64_t ImmSh = static_cast<uint64_t>(Imm) >> Shift;
808 // If the shifted value fits 32 bits.
809 if (isInt32(ImmSh)) {
810 // Go with the shifted value.
813 // Still stuck with a 64 bit value.
820 // Intermediate operand.
823 // Handle first 32 bits.
824 unsigned Lo = Imm & 0xFFFF;
825 unsigned Hi = (Imm >> 16) & 0xFFFF;
830 Result = CurDAG->getTargetNode(PPC::LI8, dl, MVT::i64, getI32Imm(Lo));
832 // Handle the Hi bits.
833 unsigned OpC = Hi ? PPC::LIS8 : PPC::LI8;
834 Result = CurDAG->getTargetNode(OpC, dl, MVT::i64, getI32Imm(Hi));
836 Result = CurDAG->getTargetNode(PPC::ORI8, dl, MVT::i64,
837 SDValue(Result, 0), getI32Imm(Lo));
840 Result = CurDAG->getTargetNode(PPC::LIS8, dl, MVT::i64, getI32Imm(Hi));
843 // If no shift, we're done.
844 if (!Shift) return Result;
846 // Shift for next step if the upper 32-bits were not zero.
848 Result = CurDAG->getTargetNode(PPC::RLDICR, dl, MVT::i64,
850 getI32Imm(Shift), getI32Imm(63 - Shift));
853 // Add in the last bits as required.
854 if ((Hi = (Remainder >> 16) & 0xFFFF)) {
855 Result = CurDAG->getTargetNode(PPC::ORIS8, dl, MVT::i64,
856 SDValue(Result, 0), getI32Imm(Hi));
858 if ((Lo = Remainder & 0xFFFF)) {
859 Result = CurDAG->getTargetNode(PPC::ORI8, dl, MVT::i64,
860 SDValue(Result, 0), getI32Imm(Lo));
869 return SelectSETCC(Op);
870 case PPCISD::GlobalBaseReg:
871 return getGlobalBaseReg();
873 case ISD::FrameIndex: {
874 int FI = cast<FrameIndexSDNode>(N)->getIndex();
875 SDValue TFI = CurDAG->getTargetFrameIndex(FI, Op.getValueType());
876 unsigned Opc = Op.getValueType() == MVT::i32 ? PPC::ADDI : PPC::ADDI8;
878 return CurDAG->SelectNodeTo(N, Opc, Op.getValueType(), TFI,
880 return CurDAG->getTargetNode(Opc, dl, Op.getValueType(), TFI,
885 SDValue InFlag = N->getOperand(1);
886 // Use MFOCRF if supported.
887 if (PPCSubTarget.isGigaProcessor())
888 return CurDAG->getTargetNode(PPC::MFOCRF, dl, MVT::i32,
889 N->getOperand(0), InFlag);
891 return CurDAG->getTargetNode(PPC::MFCR, dl, MVT::i32, InFlag);
895 // FIXME: since this depends on the setting of the carry flag from the srawi
896 // we should really be making notes about that for the scheduler.
897 // FIXME: It sure would be nice if we could cheaply recognize the
898 // srl/add/sra pattern the dag combiner will generate for this as
899 // sra/addze rather than having to handle sdiv ourselves. oh well.
901 if (isInt32Immediate(N->getOperand(1), Imm)) {
902 SDValue N0 = N->getOperand(0);
903 if ((signed)Imm > 0 && isPowerOf2_32(Imm)) {
905 CurDAG->getTargetNode(PPC::SRAWI, dl, MVT::i32, MVT::Flag,
906 N0, getI32Imm(Log2_32(Imm)));
907 return CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32,
908 SDValue(Op, 0), SDValue(Op, 1));
909 } else if ((signed)Imm < 0 && isPowerOf2_32(-Imm)) {
911 CurDAG->getTargetNode(PPC::SRAWI, dl, MVT::i32, MVT::Flag,
912 N0, getI32Imm(Log2_32(-Imm)));
914 SDValue(CurDAG->getTargetNode(PPC::ADDZE, dl, MVT::i32,
915 SDValue(Op, 0), SDValue(Op, 1)),
917 return CurDAG->SelectNodeTo(N, PPC::NEG, MVT::i32, PT);
921 // Other cases are autogenerated.
926 // Handle preincrement loads.
927 LoadSDNode *LD = cast<LoadSDNode>(Op);
928 MVT LoadedVT = LD->getMemoryVT();
930 // Normal loads are handled by code generated from the .td file.
931 if (LD->getAddressingMode() != ISD::PRE_INC)
934 SDValue Offset = LD->getOffset();
935 if (isa<ConstantSDNode>(Offset) ||
936 Offset.getOpcode() == ISD::TargetGlobalAddress) {
939 bool isSExt = LD->getExtensionType() == ISD::SEXTLOAD;
940 if (LD->getValueType(0) != MVT::i64) {
941 // Handle PPC32 integer and normal FP loads.
942 assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load");
943 switch (LoadedVT.getSimpleVT()) {
944 default: LLVM_UNREACHABLE("Invalid PPC load type!");
945 case MVT::f64: Opcode = PPC::LFDU; break;
946 case MVT::f32: Opcode = PPC::LFSU; break;
947 case MVT::i32: Opcode = PPC::LWZU; break;
948 case MVT::i16: Opcode = isSExt ? PPC::LHAU : PPC::LHZU; break;
950 case MVT::i8: Opcode = PPC::LBZU; break;
953 assert(LD->getValueType(0) == MVT::i64 && "Unknown load result type!");
954 assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load");
955 switch (LoadedVT.getSimpleVT()) {
956 default: LLVM_UNREACHABLE("Invalid PPC load type!");
957 case MVT::i64: Opcode = PPC::LDU; break;
958 case MVT::i32: Opcode = PPC::LWZU8; break;
959 case MVT::i16: Opcode = isSExt ? PPC::LHAU8 : PPC::LHZU8; break;
961 case MVT::i8: Opcode = PPC::LBZU8; break;
965 SDValue Chain = LD->getChain();
966 SDValue Base = LD->getBasePtr();
967 SDValue Ops[] = { Offset, Base, Chain };
969 return CurDAG->getTargetNode(Opcode, dl, LD->getValueType(0),
970 PPCLowering.getPointerTy(),
973 LLVM_UNREACHABLE("R+R preindex loads not supported yet!");
978 unsigned Imm, Imm2, SH, MB, ME;
980 // If this is an and of a value rotated between 0 and 31 bits and then and'd
981 // with a mask, emit rlwinm
982 if (isInt32Immediate(N->getOperand(1), Imm) &&
983 isRotateAndMask(N->getOperand(0).getNode(), Imm, false, SH, MB, ME)) {
984 SDValue Val = N->getOperand(0).getOperand(0);
985 SDValue Ops[] = { Val, getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) };
986 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
988 // If this is just a masked value where the input is not handled above, and
989 // is not a rotate-left (handled by a pattern in the .td file), emit rlwinm
990 if (isInt32Immediate(N->getOperand(1), Imm) &&
991 isRunOfOnes(Imm, MB, ME) &&
992 N->getOperand(0).getOpcode() != ISD::ROTL) {
993 SDValue Val = N->getOperand(0);
994 SDValue Ops[] = { Val, getI32Imm(0), getI32Imm(MB), getI32Imm(ME) };
995 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
997 // AND X, 0 -> 0, not "rlwinm 32".
998 if (isInt32Immediate(N->getOperand(1), Imm) && (Imm == 0)) {
999 ReplaceUses(SDValue(N, 0), N->getOperand(1));
1002 // ISD::OR doesn't get all the bitfield insertion fun.
1003 // (and (or x, c1), c2) where isRunOfOnes(~(c1^c2)) is a bitfield insert
1004 if (isInt32Immediate(N->getOperand(1), Imm) &&
1005 N->getOperand(0).getOpcode() == ISD::OR &&
1006 isInt32Immediate(N->getOperand(0).getOperand(1), Imm2)) {
1009 if (isRunOfOnes(Imm, MB, ME)) {
1010 SDValue Ops[] = { N->getOperand(0).getOperand(0),
1011 N->getOperand(0).getOperand(1),
1012 getI32Imm(0), getI32Imm(MB),getI32Imm(ME) };
1013 return CurDAG->getTargetNode(PPC::RLWIMI, dl, MVT::i32, Ops, 5);
1017 // Other cases are autogenerated.
1021 if (N->getValueType(0) == MVT::i32)
1022 if (SDNode *I = SelectBitfieldInsert(N))
1025 // Other cases are autogenerated.
1028 unsigned Imm, SH, MB, ME;
1029 if (isOpcWithIntImmediate(N->getOperand(0).getNode(), ISD::AND, Imm) &&
1030 isRotateAndMask(N, Imm, true, SH, MB, ME)) {
1031 SDValue Ops[] = { N->getOperand(0).getOperand(0),
1032 getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) };
1033 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
1036 // Other cases are autogenerated.
1040 unsigned Imm, SH, MB, ME;
1041 if (isOpcWithIntImmediate(N->getOperand(0).getNode(), ISD::AND, Imm) &&
1042 isRotateAndMask(N, Imm, true, SH, MB, ME)) {
1043 SDValue Ops[] = { N->getOperand(0).getOperand(0),
1044 getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) };
1045 return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4);
1048 // Other cases are autogenerated.
1051 case ISD::SELECT_CC: {
1052 ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(4))->get();
1054 // Handle the setcc cases here. select_cc lhs, 0, 1, 0, cc
1055 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N->getOperand(1)))
1056 if (ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N->getOperand(2)))
1057 if (ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N->getOperand(3)))
1058 if (N1C->isNullValue() && N3C->isNullValue() &&
1059 N2C->getZExtValue() == 1ULL && CC == ISD::SETNE &&
1060 // FIXME: Implement this optzn for PPC64.
1061 N->getValueType(0) == MVT::i32) {
1063 CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag,
1064 N->getOperand(0), getI32Imm(~0U));
1065 return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32,
1066 SDValue(Tmp, 0), N->getOperand(0),
1070 SDValue CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC, dl);
1071 unsigned BROpc = getPredicateForSetCC(CC);
1073 unsigned SelectCCOp;
1074 if (N->getValueType(0) == MVT::i32)
1075 SelectCCOp = PPC::SELECT_CC_I4;
1076 else if (N->getValueType(0) == MVT::i64)
1077 SelectCCOp = PPC::SELECT_CC_I8;
1078 else if (N->getValueType(0) == MVT::f32)
1079 SelectCCOp = PPC::SELECT_CC_F4;
1080 else if (N->getValueType(0) == MVT::f64)
1081 SelectCCOp = PPC::SELECT_CC_F8;
1083 SelectCCOp = PPC::SELECT_CC_VRRC;
1085 SDValue Ops[] = { CCReg, N->getOperand(2), N->getOperand(3),
1087 return CurDAG->SelectNodeTo(N, SelectCCOp, N->getValueType(0), Ops, 4);
1089 case PPCISD::COND_BRANCH: {
1090 // Op #0 is the Chain.
1091 // Op #1 is the PPC::PRED_* number.
1093 // Op #3 is the Dest MBB
1094 // Op #4 is the Flag.
1095 // Prevent PPC::PRED_* from being selected into LI.
1097 getI32Imm(cast<ConstantSDNode>(N->getOperand(1))->getZExtValue());
1098 SDValue Ops[] = { Pred, N->getOperand(2), N->getOperand(3),
1099 N->getOperand(0), N->getOperand(4) };
1100 return CurDAG->SelectNodeTo(N, PPC::BCC, MVT::Other, Ops, 5);
1103 ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(1))->get();
1104 SDValue CondCode = SelectCC(N->getOperand(2), N->getOperand(3), CC, dl);
1105 SDValue Ops[] = { getI32Imm(getPredicateForSetCC(CC)), CondCode,
1106 N->getOperand(4), N->getOperand(0) };
1107 return CurDAG->SelectNodeTo(N, PPC::BCC, MVT::Other, Ops, 4);
1110 // FIXME: Should custom lower this.
1111 SDValue Chain = N->getOperand(0);
1112 SDValue Target = N->getOperand(1);
1113 unsigned Opc = Target.getValueType() == MVT::i32 ? PPC::MTCTR : PPC::MTCTR8;
1114 Chain = SDValue(CurDAG->getTargetNode(Opc, dl, MVT::Other, Target,
1116 return CurDAG->SelectNodeTo(N, PPC::BCTR, MVT::Other, Chain);
1118 case ISD::DECLARE: {
1119 SDValue Chain = N->getOperand(0);
1120 SDValue N1 = N->getOperand(1);
1121 SDValue N2 = N->getOperand(2);
1122 FrameIndexSDNode *FINode = dyn_cast<FrameIndexSDNode>(N1);
1124 // FIXME: We need to handle this for VLAs.
1126 ReplaceUses(Op.getValue(0), Chain);
1130 if (N2.getOpcode() == ISD::ADD) {
1131 if (N2.getOperand(0).getOpcode() == ISD::ADD &&
1132 N2.getOperand(0).getOperand(0).getOpcode() == PPCISD::GlobalBaseReg &&
1133 N2.getOperand(0).getOperand(1).getOpcode() == PPCISD::Hi &&
1134 N2.getOperand(1).getOpcode() == PPCISD::Lo)
1135 N2 = N2.getOperand(0).getOperand(1).getOperand(0);
1136 else if (N2.getOperand(0).getOpcode() == ISD::ADD &&
1137 N2.getOperand(0).getOperand(0).getOpcode() == PPCISD::GlobalBaseReg &&
1138 N2.getOperand(0).getOperand(1).getOpcode() == PPCISD::Lo &&
1139 N2.getOperand(1).getOpcode() == PPCISD::Hi)
1140 N2 = N2.getOperand(0).getOperand(1).getOperand(0);
1141 else if (N2.getOperand(0).getOpcode() == PPCISD::Hi &&
1142 N2.getOperand(1).getOpcode() == PPCISD::Lo)
1143 N2 = N2.getOperand(0).getOperand(0);
1146 // If we don't have a global address here, the debug info is mangled, just
1148 if (!isa<GlobalAddressSDNode>(N2)) {
1149 ReplaceUses(Op.getValue(0), Chain);
1152 int FI = cast<FrameIndexSDNode>(N1)->getIndex();
1153 GlobalValue *GV = cast<GlobalAddressSDNode>(N2)->getGlobal();
1154 SDValue Tmp1 = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy());
1155 SDValue Tmp2 = CurDAG->getTargetGlobalAddress(GV, TLI.getPointerTy());
1156 return CurDAG->SelectNodeTo(N, TargetInstrInfo::DECLARE,
1157 MVT::Other, Tmp1, Tmp2, Chain);
1161 return SelectCode(Op);
1166 /// createPPCISelDag - This pass converts a legalized DAG into a
1167 /// PowerPC-specific DAG, ready for instruction scheduling.
1169 FunctionPass *llvm::createPPCISelDag(PPCTargetMachine &TM) {
1170 return new PPCDAGToDAGISel(TM);