1//===-- PPCISelDAGToDAG.cpp - PPC --pattern matching inst selector --------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines a pattern matching instruction selector for PowerPC,
11// converting from a legalized dag to a PPC dag.
12//
13//===----------------------------------------------------------------------===//
14
15#include "PPC.h"
16#include "MCTargetDesc/PPCPredicates.h"
17#include "PPCTargetMachine.h"
18#include "llvm/CodeGen/MachineFunction.h"
19#include "llvm/CodeGen/MachineInstrBuilder.h"
20#include "llvm/CodeGen/MachineRegisterInfo.h"
21#include "llvm/CodeGen/SelectionDAG.h"
22#include "llvm/CodeGen/SelectionDAGISel.h"
23#include "llvm/IR/Constants.h"
24#include "llvm/IR/Function.h"
25#include "llvm/IR/GlobalAlias.h"
26#include "llvm/IR/GlobalValue.h"
27#include "llvm/IR/GlobalVariable.h"
28#include "llvm/IR/Intrinsics.h"
29#include "llvm/Support/CommandLine.h"
30#include "llvm/Support/Debug.h"
31#include "llvm/Support/ErrorHandling.h"
32#include "llvm/Support/MathExtras.h"
33#include "llvm/Support/raw_ostream.h"
34#include "llvm/Target/TargetOptions.h"
35using namespace llvm;
36
37#define DEBUG_TYPE "ppc-codegen"
38
39// FIXME: Remove this once the bug has been fixed!
40cl::opt<bool> ANDIGlueBug("expose-ppc-andi-glue-bug",
41cl::desc("expose the ANDI glue bug on PPC"), cl::Hidden);
42
43namespace llvm {
44  void initializePPCDAGToDAGISelPass(PassRegistry&);
45}
46
47namespace {
48  //===--------------------------------------------------------------------===//
49  /// PPCDAGToDAGISel - PPC specific code to select PPC machine
50  /// instructions for SelectionDAG operations.
51  ///
52  class PPCDAGToDAGISel : public SelectionDAGISel {
53    const PPCTargetMachine &TM;
54    const PPCTargetLowering *PPCLowering;
55    const PPCSubtarget *PPCSubTarget;
56    unsigned GlobalBaseReg;
57  public:
58    explicit PPCDAGToDAGISel(PPCTargetMachine &tm)
59      : SelectionDAGISel(tm), TM(tm),
60        PPCLowering(TM.getTargetLowering()),
61        PPCSubTarget(TM.getSubtargetImpl()) {
62      initializePPCDAGToDAGISelPass(*PassRegistry::getPassRegistry());
63    }
64
65    bool runOnMachineFunction(MachineFunction &MF) override {
66      // Make sure we re-emit a set of the global base reg if necessary
67      GlobalBaseReg = 0;
68      PPCLowering = TM.getTargetLowering();
69      PPCSubTarget = TM.getSubtargetImpl();
70      SelectionDAGISel::runOnMachineFunction(MF);
71
72      if (!PPCSubTarget->isSVR4ABI())
73        InsertVRSaveCode(MF);
74
75      return true;
76    }
77
78    void PostprocessISelDAG() override;
79
80    /// getI32Imm - Return a target constant with the specified value, of type
81    /// i32.
82    inline SDValue getI32Imm(unsigned Imm) {
83      return CurDAG->getTargetConstant(Imm, MVT::i32);
84    }
85
86    /// getI64Imm - Return a target constant with the specified value, of type
87    /// i64.
88    inline SDValue getI64Imm(uint64_t Imm) {
89      return CurDAG->getTargetConstant(Imm, MVT::i64);
90    }
91
92    /// getSmallIPtrImm - Return a target constant of pointer type.
93    inline SDValue getSmallIPtrImm(unsigned Imm) {
94      return CurDAG->getTargetConstant(Imm, PPCLowering->getPointerTy());
95    }
96
97    /// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s
98    /// with any number of 0s on either side.  The 1s are allowed to wrap from
99    /// LSB to MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs.
100    /// 0x0F0F0000 is not, since all 1s are not contiguous.
101    static bool isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME);
102
103
104    /// isRotateAndMask - Returns true if Mask and Shift can be folded into a
105    /// rotate and mask opcode and mask operation.
106    static bool isRotateAndMask(SDNode *N, unsigned Mask, bool isShiftMask,
107                                unsigned &SH, unsigned &MB, unsigned &ME);
108
109    /// getGlobalBaseReg - insert code into the entry mbb to materialize the PIC
110    /// base register.  Return the virtual register that holds this value.
111    SDNode *getGlobalBaseReg();
112
113    // Select - Convert the specified operand from a target-independent to a
114    // target-specific node if it hasn't already been changed.
115    SDNode *Select(SDNode *N) override;
116
117    SDNode *SelectBitfieldInsert(SDNode *N);
118
119    /// SelectCC - Select a comparison of the specified values with the
120    /// specified condition code, returning the CR# of the expression.
121    SDValue SelectCC(SDValue LHS, SDValue RHS, ISD::CondCode CC, SDLoc dl);
122
123    /// SelectAddrImm - Returns true if the address N can be represented by
124    /// a base register plus a signed 16-bit displacement [r+imm].
125    bool SelectAddrImm(SDValue N, SDValue &Disp,
126                       SDValue &Base) {
127      return PPCLowering->SelectAddressRegImm(N, Disp, Base, *CurDAG, false);
128    }
129
130    /// SelectAddrImmOffs - Return true if the operand is valid for a preinc
131    /// immediate field.  Note that the operand at this point is already the
132    /// result of a prior SelectAddressRegImm call.
133    bool SelectAddrImmOffs(SDValue N, SDValue &Out) const {
134      if (N.getOpcode() == ISD::TargetConstant ||
135          N.getOpcode() == ISD::TargetGlobalAddress) {
136        Out = N;
137        return true;
138      }
139
140      return false;
141    }
142
143    /// SelectAddrIdx - Given the specified addressed, check to see if it can be
144    /// represented as an indexed [r+r] operation.  Returns false if it can
145    /// be represented by [r+imm], which are preferred.
146    bool SelectAddrIdx(SDValue N, SDValue &Base, SDValue &Index) {
147      return PPCLowering->SelectAddressRegReg(N, Base, Index, *CurDAG);
148    }
149
150    /// SelectAddrIdxOnly - Given the specified addressed, force it to be
151    /// represented as an indexed [r+r] operation.
152    bool SelectAddrIdxOnly(SDValue N, SDValue &Base, SDValue &Index) {
153      return PPCLowering->SelectAddressRegRegOnly(N, Base, Index, *CurDAG);
154    }
155
156    /// SelectAddrImmX4 - Returns true if the address N can be represented by
157    /// a base register plus a signed 16-bit displacement that is a multiple of 4.
158    /// Suitable for use by STD and friends.
159    bool SelectAddrImmX4(SDValue N, SDValue &Disp, SDValue &Base) {
160      return PPCLowering->SelectAddressRegImm(N, Disp, Base, *CurDAG, true);
161    }
162
163    // Select an address into a single register.
164    bool SelectAddr(SDValue N, SDValue &Base) {
165      Base = N;
166      return true;
167    }
168
169    /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
170    /// inline asm expressions.  It is always correct to compute the value into
171    /// a register.  The case of adding a (possibly relocatable) constant to a
172    /// register can be improved, but it is wrong to substitute Reg+Reg for
173    /// Reg in an asm, because the load or store opcode would have to change.
174   bool SelectInlineAsmMemoryOperand(const SDValue &Op,
175                                      char ConstraintCode,
176                                      std::vector<SDValue> &OutOps) override {
177      OutOps.push_back(Op);
178      return false;
179    }
180
181    void InsertVRSaveCode(MachineFunction &MF);
182
183    const char *getPassName() const override {
184      return "PowerPC DAG->DAG Pattern Instruction Selection";
185    }
186
187// Include the pieces autogenerated from the target description.
188#include "PPCGenDAGISel.inc"
189
190private:
191    SDNode *SelectSETCC(SDNode *N);
192
193    void PeepholePPC64();
194    void PeepholeCROps();
195
196    bool AllUsersSelectZero(SDNode *N);
197    void SwapAllSelectUsers(SDNode *N);
198  };
199}
200
201/// InsertVRSaveCode - Once the entire function has been instruction selected,
202/// all virtual registers are created and all machine instructions are built,
203/// check to see if we need to save/restore VRSAVE.  If so, do it.
204void PPCDAGToDAGISel::InsertVRSaveCode(MachineFunction &Fn) {
205  // Check to see if this function uses vector registers, which means we have to
206  // save and restore the VRSAVE register and update it with the regs we use.
207  //
208  // In this case, there will be virtual registers of vector type created
209  // by the scheduler.  Detect them now.
210  bool HasVectorVReg = false;
211  for (unsigned i = 0, e = RegInfo->getNumVirtRegs(); i != e; ++i) {
212    unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
213    if (RegInfo->getRegClass(Reg) == &PPC::VRRCRegClass) {
214      HasVectorVReg = true;
215      break;
216    }
217  }
218  if (!HasVectorVReg) return;  // nothing to do.
219
220  // If we have a vector register, we want to emit code into the entry and exit
221  // blocks to save and restore the VRSAVE register.  We do this here (instead
222  // of marking all vector instructions as clobbering VRSAVE) for two reasons:
223  //
224  // 1. This (trivially) reduces the load on the register allocator, by not
225  //    having to represent the live range of the VRSAVE register.
226  // 2. This (more significantly) allows us to create a temporary virtual
227  //    register to hold the saved VRSAVE value, allowing this temporary to be
228  //    register allocated, instead of forcing it to be spilled to the stack.
229
230  // Create two vregs - one to hold the VRSAVE register that is live-in to the
231  // function and one for the value after having bits or'd into it.
232  unsigned InVRSAVE = RegInfo->createVirtualRegister(&PPC::GPRCRegClass);
233  unsigned UpdatedVRSAVE = RegInfo->createVirtualRegister(&PPC::GPRCRegClass);
234
235  const TargetInstrInfo &TII = *TM.getInstrInfo();
236  MachineBasicBlock &EntryBB = *Fn.begin();
237  DebugLoc dl;
238  // Emit the following code into the entry block:
239  // InVRSAVE = MFVRSAVE
240  // UpdatedVRSAVE = UPDATE_VRSAVE InVRSAVE
241  // MTVRSAVE UpdatedVRSAVE
242  MachineBasicBlock::iterator IP = EntryBB.begin();  // Insert Point
243  BuildMI(EntryBB, IP, dl, TII.get(PPC::MFVRSAVE), InVRSAVE);
244  BuildMI(EntryBB, IP, dl, TII.get(PPC::UPDATE_VRSAVE),
245          UpdatedVRSAVE).addReg(InVRSAVE);
246  BuildMI(EntryBB, IP, dl, TII.get(PPC::MTVRSAVE)).addReg(UpdatedVRSAVE);
247
248  // Find all return blocks, outputting a restore in each epilog.
249  for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) {
250    if (!BB->empty() && BB->back().isReturn()) {
251      IP = BB->end(); --IP;
252
253      // Skip over all terminator instructions, which are part of the return
254      // sequence.
255      MachineBasicBlock::iterator I2 = IP;
256      while (I2 != BB->begin() && (--I2)->isTerminator())
257        IP = I2;
258
259      // Emit: MTVRSAVE InVRSave
260      BuildMI(*BB, IP, dl, TII.get(PPC::MTVRSAVE)).addReg(InVRSAVE);
261    }
262  }
263}
264
265
266/// getGlobalBaseReg - Output the instructions required to put the
267/// base address to use for accessing globals into a register.
268///
269SDNode *PPCDAGToDAGISel::getGlobalBaseReg() {
270  if (!GlobalBaseReg) {
271    const TargetInstrInfo &TII = *TM.getInstrInfo();
272    // Insert the set of GlobalBaseReg into the first MBB of the function
273    MachineBasicBlock &FirstMBB = MF->front();
274    MachineBasicBlock::iterator MBBI = FirstMBB.begin();
275    DebugLoc dl;
276
277    if (PPCLowering->getPointerTy() == MVT::i32) {
278      GlobalBaseReg = RegInfo->createVirtualRegister(&PPC::GPRC_NOR0RegClass);
279      BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR));
280      BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR), GlobalBaseReg);
281    } else {
282      GlobalBaseReg = RegInfo->createVirtualRegister(&PPC::G8RC_NOX0RegClass);
283      BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR8));
284      BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR8), GlobalBaseReg);
285    }
286  }
287  return CurDAG->getRegister(GlobalBaseReg,
288                             PPCLowering->getPointerTy()).getNode();
289}
290
291/// isIntS16Immediate - This method tests to see if the node is either a 32-bit
292/// or 64-bit immediate, and if the value can be accurately represented as a
293/// sign extension from a 16-bit value.  If so, this returns true and the
294/// immediate.
295static bool isIntS16Immediate(SDNode *N, short &Imm) {
296  if (N->getOpcode() != ISD::Constant)
297    return false;
298
299  Imm = (short)cast<ConstantSDNode>(N)->getZExtValue();
300  if (N->getValueType(0) == MVT::i32)
301    return Imm == (int32_t)cast<ConstantSDNode>(N)->getZExtValue();
302  else
303    return Imm == (int64_t)cast<ConstantSDNode>(N)->getZExtValue();
304}
305
306static bool isIntS16Immediate(SDValue Op, short &Imm) {
307  return isIntS16Immediate(Op.getNode(), Imm);
308}
309
310
311/// isInt32Immediate - This method tests to see if the node is a 32-bit constant
312/// operand. If so Imm will receive the 32-bit value.
313static bool isInt32Immediate(SDNode *N, unsigned &Imm) {
314  if (N->getOpcode() == ISD::Constant && N->getValueType(0) == MVT::i32) {
315    Imm = cast<ConstantSDNode>(N)->getZExtValue();
316    return true;
317  }
318  return false;
319}
320
321/// isInt64Immediate - This method tests to see if the node is a 64-bit constant
322/// operand.  If so Imm will receive the 64-bit value.
323static bool isInt64Immediate(SDNode *N, uint64_t &Imm) {
324  if (N->getOpcode() == ISD::Constant && N->getValueType(0) == MVT::i64) {
325    Imm = cast<ConstantSDNode>(N)->getZExtValue();
326    return true;
327  }
328  return false;
329}
330
331// isInt32Immediate - This method tests to see if a constant operand.
332// If so Imm will receive the 32 bit value.
333static bool isInt32Immediate(SDValue N, unsigned &Imm) {
334  return isInt32Immediate(N.getNode(), Imm);
335}
336
337
338// isOpcWithIntImmediate - This method tests to see if the node is a specific
339// opcode and that it has a immediate integer right operand.
340// If so Imm will receive the 32 bit value.
341static bool isOpcWithIntImmediate(SDNode *N, unsigned Opc, unsigned& Imm) {
342  return N->getOpcode() == Opc
343         && isInt32Immediate(N->getOperand(1).getNode(), Imm);
344}
345
346bool PPCDAGToDAGISel::isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME) {
347  if (!Val)
348    return false;
349
350  if (isShiftedMask_32(Val)) {
351    // look for the first non-zero bit
352    MB = countLeadingZeros(Val);
353    // look for the first zero bit after the run of ones
354    ME = countLeadingZeros((Val - 1) ^ Val);
355    return true;
356  } else {
357    Val = ~Val; // invert mask
358    if (isShiftedMask_32(Val)) {
359      // effectively look for the first zero bit
360      ME = countLeadingZeros(Val) - 1;
361      // effectively look for the first one bit after the run of zeros
362      MB = countLeadingZeros((Val - 1) ^ Val) + 1;
363      return true;
364    }
365  }
366  // no run present
367  return false;
368}
369
370bool PPCDAGToDAGISel::isRotateAndMask(SDNode *N, unsigned Mask,
371                                      bool isShiftMask, unsigned &SH,
372                                      unsigned &MB, unsigned &ME) {
373  // Don't even go down this path for i64, since different logic will be
374  // necessary for rldicl/rldicr/rldimi.
375  if (N->getValueType(0) != MVT::i32)
376    return false;
377
378  unsigned Shift  = 32;
379  unsigned Indeterminant = ~0;  // bit mask marking indeterminant results
380  unsigned Opcode = N->getOpcode();
381  if (N->getNumOperands() != 2 ||
382      !isInt32Immediate(N->getOperand(1).getNode(), Shift) || (Shift > 31))
383    return false;
384
385  if (Opcode == ISD::SHL) {
386    // apply shift left to mask if it comes first
387    if (isShiftMask) Mask = Mask << Shift;
388    // determine which bits are made indeterminant by shift
389    Indeterminant = ~(0xFFFFFFFFu << Shift);
390  } else if (Opcode == ISD::SRL) {
391    // apply shift right to mask if it comes first
392    if (isShiftMask) Mask = Mask >> Shift;
393    // determine which bits are made indeterminant by shift
394    Indeterminant = ~(0xFFFFFFFFu >> Shift);
395    // adjust for the left rotate
396    Shift = 32 - Shift;
397  } else if (Opcode == ISD::ROTL) {
398    Indeterminant = 0;
399  } else {
400    return false;
401  }
402
403  // if the mask doesn't intersect any Indeterminant bits
404  if (Mask && !(Mask & Indeterminant)) {
405    SH = Shift & 31;
406    // make sure the mask is still a mask (wrap arounds may not be)
407    return isRunOfOnes(Mask, MB, ME);
408  }
409  return false;
410}
411
412/// SelectBitfieldInsert - turn an or of two masked values into
413/// the rotate left word immediate then mask insert (rlwimi) instruction.
414SDNode *PPCDAGToDAGISel::SelectBitfieldInsert(SDNode *N) {
415  SDValue Op0 = N->getOperand(0);
416  SDValue Op1 = N->getOperand(1);
417  SDLoc dl(N);
418
419  APInt LKZ, LKO, RKZ, RKO;
420  CurDAG->computeKnownBits(Op0, LKZ, LKO);
421  CurDAG->computeKnownBits(Op1, RKZ, RKO);
422
423  unsigned TargetMask = LKZ.getZExtValue();
424  unsigned InsertMask = RKZ.getZExtValue();
425
426  if ((TargetMask | InsertMask) == 0xFFFFFFFF) {
427    unsigned Op0Opc = Op0.getOpcode();
428    unsigned Op1Opc = Op1.getOpcode();
429    unsigned Value, SH = 0;
430    TargetMask = ~TargetMask;
431    InsertMask = ~InsertMask;
432
433    // If the LHS has a foldable shift and the RHS does not, then swap it to the
434    // RHS so that we can fold the shift into the insert.
435    if (Op0Opc == ISD::AND && Op1Opc == ISD::AND) {
436      if (Op0.getOperand(0).getOpcode() == ISD::SHL ||
437          Op0.getOperand(0).getOpcode() == ISD::SRL) {
438        if (Op1.getOperand(0).getOpcode() != ISD::SHL &&
439            Op1.getOperand(0).getOpcode() != ISD::SRL) {
440          std::swap(Op0, Op1);
441          std::swap(Op0Opc, Op1Opc);
442          std::swap(TargetMask, InsertMask);
443        }
444      }
445    } else if (Op0Opc == ISD::SHL || Op0Opc == ISD::SRL) {
446      if (Op1Opc == ISD::AND && Op1.getOperand(0).getOpcode() != ISD::SHL &&
447          Op1.getOperand(0).getOpcode() != ISD::SRL) {
448        std::swap(Op0, Op1);
449        std::swap(Op0Opc, Op1Opc);
450        std::swap(TargetMask, InsertMask);
451      }
452    }
453
454    unsigned MB, ME;
455    if (isRunOfOnes(InsertMask, MB, ME)) {
456      SDValue Tmp1, Tmp2;
457
458      if ((Op1Opc == ISD::SHL || Op1Opc == ISD::SRL) &&
459          isInt32Immediate(Op1.getOperand(1), Value)) {
460        Op1 = Op1.getOperand(0);
461        SH  = (Op1Opc == ISD::SHL) ? Value : 32 - Value;
462      }
463      if (Op1Opc == ISD::AND) {
464       // The AND mask might not be a constant, and we need to make sure that
465       // if we're going to fold the masking with the insert, all bits not
466       // know to be zero in the mask are known to be one.
467        APInt MKZ, MKO;
468        CurDAG->computeKnownBits(Op1.getOperand(1), MKZ, MKO);
469        bool CanFoldMask = InsertMask == MKO.getZExtValue();
470
471        unsigned SHOpc = Op1.getOperand(0).getOpcode();
472        if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) && CanFoldMask &&
473            isInt32Immediate(Op1.getOperand(0).getOperand(1), Value)) {
474          // Note that Value must be in range here (less than 32) because
475          // otherwise there would not be any bits set in InsertMask.
476          Op1 = Op1.getOperand(0).getOperand(0);
477          SH  = (SHOpc == ISD::SHL) ? Value : 32 - Value;
478        }
479      }
480
481      SH &= 31;
482      SDValue Ops[] = { Op0, Op1, getI32Imm(SH), getI32Imm(MB),
483                          getI32Imm(ME) };
484      return CurDAG->getMachineNode(PPC::RLWIMI, dl, MVT::i32, Ops);
485    }
486  }
487  return nullptr;
488}
489
490/// SelectCC - Select a comparison of the specified values with the specified
491/// condition code, returning the CR# of the expression.
492SDValue PPCDAGToDAGISel::SelectCC(SDValue LHS, SDValue RHS,
493                                    ISD::CondCode CC, SDLoc dl) {
494  // Always select the LHS.
495  unsigned Opc;
496
497  if (LHS.getValueType() == MVT::i32) {
498    unsigned Imm;
499    if (CC == ISD::SETEQ || CC == ISD::SETNE) {
500      if (isInt32Immediate(RHS, Imm)) {
501        // SETEQ/SETNE comparison with 16-bit immediate, fold it.
502        if (isUInt<16>(Imm))
503          return SDValue(CurDAG->getMachineNode(PPC::CMPLWI, dl, MVT::i32, LHS,
504                                                getI32Imm(Imm & 0xFFFF)), 0);
505        // If this is a 16-bit signed immediate, fold it.
506        if (isInt<16>((int)Imm))
507          return SDValue(CurDAG->getMachineNode(PPC::CMPWI, dl, MVT::i32, LHS,
508                                                getI32Imm(Imm & 0xFFFF)), 0);
509
510        // For non-equality comparisons, the default code would materialize the
511        // constant, then compare against it, like this:
512        //   lis r2, 4660
513        //   ori r2, r2, 22136
514        //   cmpw cr0, r3, r2
515        // Since we are just comparing for equality, we can emit this instead:
516        //   xoris r0,r3,0x1234
517        //   cmplwi cr0,r0,0x5678
518        //   beq cr0,L6
519        SDValue Xor(CurDAG->getMachineNode(PPC::XORIS, dl, MVT::i32, LHS,
520                                           getI32Imm(Imm >> 16)), 0);
521        return SDValue(CurDAG->getMachineNode(PPC::CMPLWI, dl, MVT::i32, Xor,
522                                              getI32Imm(Imm & 0xFFFF)), 0);
523      }
524      Opc = PPC::CMPLW;
525    } else if (ISD::isUnsignedIntSetCC(CC)) {
526      if (isInt32Immediate(RHS, Imm) && isUInt<16>(Imm))
527        return SDValue(CurDAG->getMachineNode(PPC::CMPLWI, dl, MVT::i32, LHS,
528                                              getI32Imm(Imm & 0xFFFF)), 0);
529      Opc = PPC::CMPLW;
530    } else {
531      short SImm;
532      if (isIntS16Immediate(RHS, SImm))
533        return SDValue(CurDAG->getMachineNode(PPC::CMPWI, dl, MVT::i32, LHS,
534                                              getI32Imm((int)SImm & 0xFFFF)),
535                         0);
536      Opc = PPC::CMPW;
537    }
538  } else if (LHS.getValueType() == MVT::i64) {
539    uint64_t Imm;
540    if (CC == ISD::SETEQ || CC == ISD::SETNE) {
541      if (isInt64Immediate(RHS.getNode(), Imm)) {
542        // SETEQ/SETNE comparison with 16-bit immediate, fold it.
543        if (isUInt<16>(Imm))
544          return SDValue(CurDAG->getMachineNode(PPC::CMPLDI, dl, MVT::i64, LHS,
545                                                getI32Imm(Imm & 0xFFFF)), 0);
546        // If this is a 16-bit signed immediate, fold it.
547        if (isInt<16>(Imm))
548          return SDValue(CurDAG->getMachineNode(PPC::CMPDI, dl, MVT::i64, LHS,
549                                                getI32Imm(Imm & 0xFFFF)), 0);
550
551        // For non-equality comparisons, the default code would materialize the
552        // constant, then compare against it, like this:
553        //   lis r2, 4660
554        //   ori r2, r2, 22136
555        //   cmpd cr0, r3, r2
556        // Since we are just comparing for equality, we can emit this instead:
557        //   xoris r0,r3,0x1234
558        //   cmpldi cr0,r0,0x5678
559        //   beq cr0,L6
560        if (isUInt<32>(Imm)) {
561          SDValue Xor(CurDAG->getMachineNode(PPC::XORIS8, dl, MVT::i64, LHS,
562                                             getI64Imm(Imm >> 16)), 0);
563          return SDValue(CurDAG->getMachineNode(PPC::CMPLDI, dl, MVT::i64, Xor,
564                                                getI64Imm(Imm & 0xFFFF)), 0);
565        }
566      }
567      Opc = PPC::CMPLD;
568    } else if (ISD::isUnsignedIntSetCC(CC)) {
569      if (isInt64Immediate(RHS.getNode(), Imm) && isUInt<16>(Imm))
570        return SDValue(CurDAG->getMachineNode(PPC::CMPLDI, dl, MVT::i64, LHS,
571                                              getI64Imm(Imm & 0xFFFF)), 0);
572      Opc = PPC::CMPLD;
573    } else {
574      short SImm;
575      if (isIntS16Immediate(RHS, SImm))
576        return SDValue(CurDAG->getMachineNode(PPC::CMPDI, dl, MVT::i64, LHS,
577                                              getI64Imm(SImm & 0xFFFF)),
578                         0);
579      Opc = PPC::CMPD;
580    }
581  } else if (LHS.getValueType() == MVT::f32) {
582    Opc = PPC::FCMPUS;
583  } else {
584    assert(LHS.getValueType() == MVT::f64 && "Unknown vt!");
585    Opc = PPCSubTarget->hasVSX() ? PPC::XSCMPUDP : PPC::FCMPUD;
586  }
587  return SDValue(CurDAG->getMachineNode(Opc, dl, MVT::i32, LHS, RHS), 0);
588}
589
590static PPC::Predicate getPredicateForSetCC(ISD::CondCode CC) {
591  switch (CC) {
592  case ISD::SETUEQ:
593  case ISD::SETONE:
594  case ISD::SETOLE:
595  case ISD::SETOGE:
596    llvm_unreachable("Should be lowered by legalize!");
597  default: llvm_unreachable("Unknown condition!");
598  case ISD::SETOEQ:
599  case ISD::SETEQ:  return PPC::PRED_EQ;
600  case ISD::SETUNE:
601  case ISD::SETNE:  return PPC::PRED_NE;
602  case ISD::SETOLT:
603  case ISD::SETLT:  return PPC::PRED_LT;
604  case ISD::SETULE:
605  case ISD::SETLE:  return PPC::PRED_LE;
606  case ISD::SETOGT:
607  case ISD::SETGT:  return PPC::PRED_GT;
608  case ISD::SETUGE:
609  case ISD::SETGE:  return PPC::PRED_GE;
610  case ISD::SETO:   return PPC::PRED_NU;
611  case ISD::SETUO:  return PPC::PRED_UN;
612    // These two are invalid for floating point.  Assume we have int.
613  case ISD::SETULT: return PPC::PRED_LT;
614  case ISD::SETUGT: return PPC::PRED_GT;
615  }
616}
617
618/// getCRIdxForSetCC - Return the index of the condition register field
619/// associated with the SetCC condition, and whether or not the field is
620/// treated as inverted.  That is, lt = 0; ge = 0 inverted.
621static unsigned getCRIdxForSetCC(ISD::CondCode CC, bool &Invert) {
622  Invert = false;
623  switch (CC) {
624  default: llvm_unreachable("Unknown condition!");
625  case ISD::SETOLT:
626  case ISD::SETLT:  return 0;                  // Bit #0 = SETOLT
627  case ISD::SETOGT:
628  case ISD::SETGT:  return 1;                  // Bit #1 = SETOGT
629  case ISD::SETOEQ:
630  case ISD::SETEQ:  return 2;                  // Bit #2 = SETOEQ
631  case ISD::SETUO:  return 3;                  // Bit #3 = SETUO
632  case ISD::SETUGE:
633  case ISD::SETGE:  Invert = true; return 0;   // !Bit #0 = SETUGE
634  case ISD::SETULE:
635  case ISD::SETLE:  Invert = true; return 1;   // !Bit #1 = SETULE
636  case ISD::SETUNE:
637  case ISD::SETNE:  Invert = true; return 2;   // !Bit #2 = SETUNE
638  case ISD::SETO:   Invert = true; return 3;   // !Bit #3 = SETO
639  case ISD::SETUEQ:
640  case ISD::SETOGE:
641  case ISD::SETOLE:
642  case ISD::SETONE:
643    llvm_unreachable("Invalid branch code: should be expanded by legalize");
644  // These are invalid for floating point.  Assume integer.
645  case ISD::SETULT: return 0;
646  case ISD::SETUGT: return 1;
647  }
648}
649
650// getVCmpInst: return the vector compare instruction for the specified
651// vector type and condition code. Since this is for altivec specific code,
652// only support the altivec types (v16i8, v8i16, v4i32, and v4f32).
653static unsigned int getVCmpInst(MVT::SimpleValueType VecVT, ISD::CondCode CC,
654                                bool HasVSX) {
655  switch (CC) {
656    case ISD::SETEQ:
657    case ISD::SETUEQ:
658    case ISD::SETNE:
659    case ISD::SETUNE:
660      if (VecVT == MVT::v16i8)
661        return PPC::VCMPEQUB;
662      else if (VecVT == MVT::v8i16)
663        return PPC::VCMPEQUH;
664      else if (VecVT == MVT::v4i32)
665        return PPC::VCMPEQUW;
666      // v4f32 != v4f32 could be translate to unordered not equal
667      else if (VecVT == MVT::v4f32)
668        return HasVSX ? PPC::XVCMPEQSP : PPC::VCMPEQFP;
669      else if (VecVT == MVT::v2f64)
670        return PPC::XVCMPEQDP;
671      break;
672    case ISD::SETLT:
673    case ISD::SETGT:
674    case ISD::SETLE:
675    case ISD::SETGE:
676      if (VecVT == MVT::v16i8)
677        return PPC::VCMPGTSB;
678      else if (VecVT == MVT::v8i16)
679        return PPC::VCMPGTSH;
680      else if (VecVT == MVT::v4i32)
681        return PPC::VCMPGTSW;
682      else if (VecVT == MVT::v4f32)
683        return HasVSX ? PPC::XVCMPGTSP : PPC::VCMPGTFP;
684      else if (VecVT == MVT::v2f64)
685        return PPC::XVCMPGTDP;
686      break;
687    case ISD::SETULT:
688    case ISD::SETUGT:
689    case ISD::SETUGE:
690    case ISD::SETULE:
691      if (VecVT == MVT::v16i8)
692        return PPC::VCMPGTUB;
693      else if (VecVT == MVT::v8i16)
694        return PPC::VCMPGTUH;
695      else if (VecVT == MVT::v4i32)
696        return PPC::VCMPGTUW;
697      break;
698    case ISD::SETOEQ:
699      if (VecVT == MVT::v4f32)
700        return HasVSX ? PPC::XVCMPEQSP : PPC::VCMPEQFP;
701      else if (VecVT == MVT::v2f64)
702        return PPC::XVCMPEQDP;
703      break;
704    case ISD::SETOLT:
705    case ISD::SETOGT:
706    case ISD::SETOLE:
707      if (VecVT == MVT::v4f32)
708        return HasVSX ? PPC::XVCMPGTSP : PPC::VCMPGTFP;
709      else if (VecVT == MVT::v2f64)
710        return PPC::XVCMPGTDP;
711      break;
712    case ISD::SETOGE:
713      if (VecVT == MVT::v4f32)
714        return HasVSX ? PPC::XVCMPGESP : PPC::VCMPGEFP;
715      else if (VecVT == MVT::v2f64)
716        return PPC::XVCMPGEDP;
717      break;
718    default:
719      break;
720  }
721  llvm_unreachable("Invalid integer vector compare condition");
722}
723
724// getVCmpEQInst: return the equal compare instruction for the specified vector
725// type. Since this is for altivec specific code, only support the altivec
726// types (v16i8, v8i16, v4i32, and v4f32).
727static unsigned int getVCmpEQInst(MVT::SimpleValueType VecVT, bool HasVSX) {
728  switch (VecVT) {
729    case MVT::v16i8:
730      return PPC::VCMPEQUB;
731    case MVT::v8i16:
732      return PPC::VCMPEQUH;
733    case MVT::v4i32:
734      return PPC::VCMPEQUW;
735    case MVT::v4f32:
736      return HasVSX ? PPC::XVCMPEQSP : PPC::VCMPEQFP;
737    case MVT::v2f64:
738      return PPC::XVCMPEQDP;
739    default:
740      llvm_unreachable("Invalid integer vector compare condition");
741  }
742}
743
744SDNode *PPCDAGToDAGISel::SelectSETCC(SDNode *N) {
745  SDLoc dl(N);
746  unsigned Imm;
747  ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(2))->get();
748  EVT PtrVT = CurDAG->getTargetLoweringInfo().getPointerTy();
749  bool isPPC64 = (PtrVT == MVT::i64);
750
751  if (!PPCSubTarget->useCRBits() &&
752      isInt32Immediate(N->getOperand(1), Imm)) {
753    // We can codegen setcc op, imm very efficiently compared to a brcond.
754    // Check for those cases here.
755    // setcc op, 0
756    if (Imm == 0) {
757      SDValue Op = N->getOperand(0);
758      switch (CC) {
759      default: break;
760      case ISD::SETEQ: {
761        Op = SDValue(CurDAG->getMachineNode(PPC::CNTLZW, dl, MVT::i32, Op), 0);
762        SDValue Ops[] = { Op, getI32Imm(27), getI32Imm(5), getI32Imm(31) };
763        return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
764      }
765      case ISD::SETNE: {
766        if (isPPC64) break;
767        SDValue AD =
768          SDValue(CurDAG->getMachineNode(PPC::ADDIC, dl, MVT::i32, MVT::Glue,
769                                         Op, getI32Imm(~0U)), 0);
770        return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, AD, Op,
771                                    AD.getValue(1));
772      }
773      case ISD::SETLT: {
774        SDValue Ops[] = { Op, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
775        return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
776      }
777      case ISD::SETGT: {
778        SDValue T =
779          SDValue(CurDAG->getMachineNode(PPC::NEG, dl, MVT::i32, Op), 0);
780        T = SDValue(CurDAG->getMachineNode(PPC::ANDC, dl, MVT::i32, T, Op), 0);
781        SDValue Ops[] = { T, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
782        return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
783      }
784      }
785    } else if (Imm == ~0U) {        // setcc op, -1
786      SDValue Op = N->getOperand(0);
787      switch (CC) {
788      default: break;
789      case ISD::SETEQ:
790        if (isPPC64) break;
791        Op = SDValue(CurDAG->getMachineNode(PPC::ADDIC, dl, MVT::i32, MVT::Glue,
792                                            Op, getI32Imm(1)), 0);
793        return CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32,
794                              SDValue(CurDAG->getMachineNode(PPC::LI, dl,
795                                                             MVT::i32,
796                                                             getI32Imm(0)), 0),
797                                      Op.getValue(1));
798      case ISD::SETNE: {
799        if (isPPC64) break;
800        Op = SDValue(CurDAG->getMachineNode(PPC::NOR, dl, MVT::i32, Op, Op), 0);
801        SDNode *AD = CurDAG->getMachineNode(PPC::ADDIC, dl, MVT::i32, MVT::Glue,
802                                            Op, getI32Imm(~0U));
803        return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, SDValue(AD, 0),
804                                    Op, SDValue(AD, 1));
805      }
806      case ISD::SETLT: {
807        SDValue AD = SDValue(CurDAG->getMachineNode(PPC::ADDI, dl, MVT::i32, Op,
808                                                    getI32Imm(1)), 0);
809        SDValue AN = SDValue(CurDAG->getMachineNode(PPC::AND, dl, MVT::i32, AD,
810                                                    Op), 0);
811        SDValue Ops[] = { AN, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
812        return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
813      }
814      case ISD::SETGT: {
815        SDValue Ops[] = { Op, getI32Imm(1), getI32Imm(31), getI32Imm(31) };
816        Op = SDValue(CurDAG->getMachineNode(PPC::RLWINM, dl, MVT::i32, Ops),
817                     0);
818        return CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Op,
819                                    getI32Imm(1));
820      }
821      }
822    }
823  }
824
825  SDValue LHS = N->getOperand(0);
826  SDValue RHS = N->getOperand(1);
827
828  // Altivec Vector compare instructions do not set any CR register by default and
829  // vector compare operations return the same type as the operands.
830  if (LHS.getValueType().isVector()) {
831    EVT VecVT = LHS.getValueType();
832    MVT::SimpleValueType VT = VecVT.getSimpleVT().SimpleTy;
833    unsigned int VCmpInst = getVCmpInst(VT, CC, PPCSubTarget->hasVSX());
834
835    switch (CC) {
836      case ISD::SETEQ:
837      case ISD::SETOEQ:
838      case ISD::SETUEQ:
839        return CurDAG->SelectNodeTo(N, VCmpInst, VecVT, LHS, RHS);
840      case ISD::SETNE:
841      case ISD::SETONE:
842      case ISD::SETUNE: {
843        SDValue VCmp(CurDAG->getMachineNode(VCmpInst, dl, VecVT, LHS, RHS), 0);
844        return CurDAG->SelectNodeTo(N, PPCSubTarget->hasVSX() ? PPC::XXLNOR :
845                                                               PPC::VNOR,
846                                    VecVT, VCmp, VCmp);
847      }
848      case ISD::SETLT:
849      case ISD::SETOLT:
850      case ISD::SETULT:
851        return CurDAG->SelectNodeTo(N, VCmpInst, VecVT, RHS, LHS);
852      case ISD::SETGT:
853      case ISD::SETOGT:
854      case ISD::SETUGT:
855        return CurDAG->SelectNodeTo(N, VCmpInst, VecVT, LHS, RHS);
856      case ISD::SETGE:
857      case ISD::SETOGE:
858      case ISD::SETUGE: {
859        // Small optimization: Altivec provides a 'Vector Compare Greater Than
860        // or Equal To' instruction (vcmpgefp), so in this case there is no
861        // need for extra logic for the equal compare.
862        if (VecVT.getSimpleVT().isFloatingPoint()) {
863          return CurDAG->SelectNodeTo(N, VCmpInst, VecVT, LHS, RHS);
864        } else {
865          SDValue VCmpGT(CurDAG->getMachineNode(VCmpInst, dl, VecVT, LHS, RHS), 0);
866          unsigned int VCmpEQInst = getVCmpEQInst(VT, PPCSubTarget->hasVSX());
867          SDValue VCmpEQ(CurDAG->getMachineNode(VCmpEQInst, dl, VecVT, LHS, RHS), 0);
868          return CurDAG->SelectNodeTo(N, PPCSubTarget->hasVSX() ? PPC::XXLOR :
869                                                                 PPC::VOR,
870                                      VecVT, VCmpGT, VCmpEQ);
871        }
872      }
873      case ISD::SETLE:
874      case ISD::SETOLE:
875      case ISD::SETULE: {
876        SDValue VCmpLE(CurDAG->getMachineNode(VCmpInst, dl, VecVT, RHS, LHS), 0);
877        unsigned int VCmpEQInst = getVCmpEQInst(VT, PPCSubTarget->hasVSX());
878        SDValue VCmpEQ(CurDAG->getMachineNode(VCmpEQInst, dl, VecVT, LHS, RHS), 0);
879        return CurDAG->SelectNodeTo(N, PPCSubTarget->hasVSX() ? PPC::XXLOR :
880                                                               PPC::VOR,
881                                    VecVT, VCmpLE, VCmpEQ);
882      }
883      default:
884        llvm_unreachable("Invalid vector compare type: should be expanded by legalize");
885    }
886  }
887
888  if (PPCSubTarget->useCRBits())
889    return nullptr;
890
891  bool Inv;
892  unsigned Idx = getCRIdxForSetCC(CC, Inv);
893  SDValue CCReg = SelectCC(LHS, RHS, CC, dl);
894  SDValue IntCR;
895
896  // Force the ccreg into CR7.
897  SDValue CR7Reg = CurDAG->getRegister(PPC::CR7, MVT::i32);
898
899  SDValue InFlag(nullptr, 0);  // Null incoming flag value.
900  CCReg = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, CR7Reg, CCReg,
901                               InFlag).getValue(1);
902
903  IntCR = SDValue(CurDAG->getMachineNode(PPC::MFOCRF, dl, MVT::i32, CR7Reg,
904                                         CCReg), 0);
905
906  SDValue Ops[] = { IntCR, getI32Imm((32-(3-Idx)) & 31),
907                      getI32Imm(31), getI32Imm(31) };
908  if (!Inv)
909    return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
910
911  // Get the specified bit.
912  SDValue Tmp =
913    SDValue(CurDAG->getMachineNode(PPC::RLWINM, dl, MVT::i32, Ops), 0);
914  return CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Tmp, getI32Imm(1));
915}
916
917
918// Select - Convert the specified operand from a target-independent to a
919// target-specific node if it hasn't already been changed.
920SDNode *PPCDAGToDAGISel::Select(SDNode *N) {
921  SDLoc dl(N);
922  if (N->isMachineOpcode()) {
923    N->setNodeId(-1);
924    return nullptr;   // Already selected.
925  }
926
927  switch (N->getOpcode()) {
928  default: break;
929
930  case ISD::Constant: {
931    if (N->getValueType(0) == MVT::i64) {
932      // Get 64 bit value.
933      int64_t Imm = cast<ConstantSDNode>(N)->getZExtValue();
934      // Assume no remaining bits.
935      unsigned Remainder = 0;
936      // Assume no shift required.
937      unsigned Shift = 0;
938
939      // If it can't be represented as a 32 bit value.
940      if (!isInt<32>(Imm)) {
941        Shift = countTrailingZeros<uint64_t>(Imm);
942        int64_t ImmSh = static_cast<uint64_t>(Imm) >> Shift;
943
944        // If the shifted value fits 32 bits.
945        if (isInt<32>(ImmSh)) {
946          // Go with the shifted value.
947          Imm = ImmSh;
948        } else {
949          // Still stuck with a 64 bit value.
950          Remainder = Imm;
951          Shift = 32;
952          Imm >>= 32;
953        }
954      }
955
956      // Intermediate operand.
957      SDNode *Result;
958
959      // Handle first 32 bits.
960      unsigned Lo = Imm & 0xFFFF;
961      unsigned Hi = (Imm >> 16) & 0xFFFF;
962
963      // Simple value.
964      if (isInt<16>(Imm)) {
965       // Just the Lo bits.
966        Result = CurDAG->getMachineNode(PPC::LI8, dl, MVT::i64, getI32Imm(Lo));
967      } else if (Lo) {
968        // Handle the Hi bits.
969        unsigned OpC = Hi ? PPC::LIS8 : PPC::LI8;
970        Result = CurDAG->getMachineNode(OpC, dl, MVT::i64, getI32Imm(Hi));
971        // And Lo bits.
972        Result = CurDAG->getMachineNode(PPC::ORI8, dl, MVT::i64,
973                                        SDValue(Result, 0), getI32Imm(Lo));
974      } else {
975       // Just the Hi bits.
976        Result = CurDAG->getMachineNode(PPC::LIS8, dl, MVT::i64, getI32Imm(Hi));
977      }
978
979      // If no shift, we're done.
980      if (!Shift) return Result;
981
982      // Shift for next step if the upper 32-bits were not zero.
983      if (Imm) {
984        Result = CurDAG->getMachineNode(PPC::RLDICR, dl, MVT::i64,
985                                        SDValue(Result, 0),
986                                        getI32Imm(Shift),
987                                        getI32Imm(63 - Shift));
988      }
989
990      // Add in the last bits as required.
991      if ((Hi = (Remainder >> 16) & 0xFFFF)) {
992        Result = CurDAG->getMachineNode(PPC::ORIS8, dl, MVT::i64,
993                                        SDValue(Result, 0), getI32Imm(Hi));
994      }
995      if ((Lo = Remainder & 0xFFFF)) {
996        Result = CurDAG->getMachineNode(PPC::ORI8, dl, MVT::i64,
997                                        SDValue(Result, 0), getI32Imm(Lo));
998      }
999
1000      return Result;
1001    }
1002    break;
1003  }
1004
1005  case ISD::SETCC: {
1006    SDNode *SN = SelectSETCC(N);
1007    if (SN)
1008      return SN;
1009    break;
1010  }
1011  case PPCISD::GlobalBaseReg:
1012    return getGlobalBaseReg();
1013
1014  case ISD::FrameIndex: {
1015    int FI = cast<FrameIndexSDNode>(N)->getIndex();
1016    SDValue TFI = CurDAG->getTargetFrameIndex(FI, N->getValueType(0));
1017    unsigned Opc = N->getValueType(0) == MVT::i32 ? PPC::ADDI : PPC::ADDI8;
1018    if (N->hasOneUse())
1019      return CurDAG->SelectNodeTo(N, Opc, N->getValueType(0), TFI,
1020                                  getSmallIPtrImm(0));
1021    return CurDAG->getMachineNode(Opc, dl, N->getValueType(0), TFI,
1022                                  getSmallIPtrImm(0));
1023  }
1024
1025  case PPCISD::MFOCRF: {
1026    SDValue InFlag = N->getOperand(1);
1027    return CurDAG->getMachineNode(PPC::MFOCRF, dl, MVT::i32,
1028                                  N->getOperand(0), InFlag);
1029  }
1030
1031  case ISD::SDIV: {
1032    // FIXME: since this depends on the setting of the carry flag from the srawi
1033    //        we should really be making notes about that for the scheduler.
1034    // FIXME: It sure would be nice if we could cheaply recognize the
1035    //        srl/add/sra pattern the dag combiner will generate for this as
1036    //        sra/addze rather than having to handle sdiv ourselves.  oh well.
1037    unsigned Imm;
1038    if (isInt32Immediate(N->getOperand(1), Imm)) {
1039      SDValue N0 = N->getOperand(0);
1040      if ((signed)Imm > 0 && isPowerOf2_32(Imm)) {
1041        SDNode *Op =
1042          CurDAG->getMachineNode(PPC::SRAWI, dl, MVT::i32, MVT::Glue,
1043                                 N0, getI32Imm(Log2_32(Imm)));
1044        return CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32,
1045                                    SDValue(Op, 0), SDValue(Op, 1));
1046      } else if ((signed)Imm < 0 && isPowerOf2_32(-Imm)) {
1047        SDNode *Op =
1048          CurDAG->getMachineNode(PPC::SRAWI, dl, MVT::i32, MVT::Glue,
1049                                 N0, getI32Imm(Log2_32(-Imm)));
1050        SDValue PT =
1051          SDValue(CurDAG->getMachineNode(PPC::ADDZE, dl, MVT::i32,
1052                                         SDValue(Op, 0), SDValue(Op, 1)),
1053                    0);
1054        return CurDAG->SelectNodeTo(N, PPC::NEG, MVT::i32, PT);
1055      }
1056    }
1057
1058    // Other cases are autogenerated.
1059    break;
1060  }
1061
1062  case ISD::LOAD: {
1063    // Handle preincrement loads.
1064    LoadSDNode *LD = cast<LoadSDNode>(N);
1065    EVT LoadedVT = LD->getMemoryVT();
1066
1067    // Normal loads are handled by code generated from the .td file.
1068    if (LD->getAddressingMode() != ISD::PRE_INC)
1069      break;
1070
1071    SDValue Offset = LD->getOffset();
1072    if (Offset.getOpcode() == ISD::TargetConstant ||
1073        Offset.getOpcode() == ISD::TargetGlobalAddress) {
1074
1075      unsigned Opcode;
1076      bool isSExt = LD->getExtensionType() == ISD::SEXTLOAD;
1077      if (LD->getValueType(0) != MVT::i64) {
1078        // Handle PPC32 integer and normal FP loads.
1079        assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load");
1080        switch (LoadedVT.getSimpleVT().SimpleTy) {
1081          default: llvm_unreachable("Invalid PPC load type!");
1082          case MVT::f64: Opcode = PPC::LFDU; break;
1083          case MVT::f32: Opcode = PPC::LFSU; break;
1084          case MVT::i32: Opcode = PPC::LWZU; break;
1085          case MVT::i16: Opcode = isSExt ? PPC::LHAU : PPC::LHZU; break;
1086          case MVT::i1:
1087          case MVT::i8:  Opcode = PPC::LBZU; break;
1088        }
1089      } else {
1090        assert(LD->getValueType(0) == MVT::i64 && "Unknown load result type!");
1091        assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load");
1092        switch (LoadedVT.getSimpleVT().SimpleTy) {
1093          default: llvm_unreachable("Invalid PPC load type!");
1094          case MVT::i64: Opcode = PPC::LDU; break;
1095          case MVT::i32: Opcode = PPC::LWZU8; break;
1096          case MVT::i16: Opcode = isSExt ? PPC::LHAU8 : PPC::LHZU8; break;
1097          case MVT::i1:
1098          case MVT::i8:  Opcode = PPC::LBZU8; break;
1099        }
1100      }
1101
1102      SDValue Chain = LD->getChain();
1103      SDValue Base = LD->getBasePtr();
1104      SDValue Ops[] = { Offset, Base, Chain };
1105      return CurDAG->getMachineNode(Opcode, dl, LD->getValueType(0),
1106                                    PPCLowering->getPointerTy(),
1107                                    MVT::Other, Ops);
1108    } else {
1109      unsigned Opcode;
1110      bool isSExt = LD->getExtensionType() == ISD::SEXTLOAD;
1111      if (LD->getValueType(0) != MVT::i64) {
1112        // Handle PPC32 integer and normal FP loads.
1113        assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load");
1114        switch (LoadedVT.getSimpleVT().SimpleTy) {
1115          default: llvm_unreachable("Invalid PPC load type!");
1116          case MVT::f64: Opcode = PPC::LFDUX; break;
1117          case MVT::f32: Opcode = PPC::LFSUX; break;
1118          case MVT::i32: Opcode = PPC::LWZUX; break;
1119          case MVT::i16: Opcode = isSExt ? PPC::LHAUX : PPC::LHZUX; break;
1120          case MVT::i1:
1121          case MVT::i8:  Opcode = PPC::LBZUX; break;
1122        }
1123      } else {
1124        assert(LD->getValueType(0) == MVT::i64 && "Unknown load result type!");
1125        assert((!isSExt || LoadedVT == MVT::i16 || LoadedVT == MVT::i32) &&
1126               "Invalid sext update load");
1127        switch (LoadedVT.getSimpleVT().SimpleTy) {
1128          default: llvm_unreachable("Invalid PPC load type!");
1129          case MVT::i64: Opcode = PPC::LDUX; break;
1130          case MVT::i32: Opcode = isSExt ? PPC::LWAUX  : PPC::LWZUX8; break;
1131          case MVT::i16: Opcode = isSExt ? PPC::LHAUX8 : PPC::LHZUX8; break;
1132          case MVT::i1:
1133          case MVT::i8:  Opcode = PPC::LBZUX8; break;
1134        }
1135      }
1136
1137      SDValue Chain = LD->getChain();
1138      SDValue Base = LD->getBasePtr();
1139      SDValue Ops[] = { Base, Offset, Chain };
1140      return CurDAG->getMachineNode(Opcode, dl, LD->getValueType(0),
1141                                    PPCLowering->getPointerTy(),
1142                                    MVT::Other, Ops);
1143    }
1144  }
1145
1146  case ISD::AND: {
1147    unsigned Imm, Imm2, SH, MB, ME;
1148    uint64_t Imm64;
1149
1150    // If this is an and of a value rotated between 0 and 31 bits and then and'd
1151    // with a mask, emit rlwinm
1152    if (isInt32Immediate(N->getOperand(1), Imm) &&
1153        isRotateAndMask(N->getOperand(0).getNode(), Imm, false, SH, MB, ME)) {
1154      SDValue Val = N->getOperand(0).getOperand(0);
1155      SDValue Ops[] = { Val, getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) };
1156      return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
1157    }
1158    // If this is just a masked value where the input is not handled above, and
1159    // is not a rotate-left (handled by a pattern in the .td file), emit rlwinm
1160    if (isInt32Immediate(N->getOperand(1), Imm) &&
1161        isRunOfOnes(Imm, MB, ME) &&
1162        N->getOperand(0).getOpcode() != ISD::ROTL) {
1163      SDValue Val = N->getOperand(0);
1164      SDValue Ops[] = { Val, getI32Imm(0), getI32Imm(MB), getI32Imm(ME) };
1165      return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
1166    }
1167    // If this is a 64-bit zero-extension mask, emit rldicl.
1168    if (isInt64Immediate(N->getOperand(1).getNode(), Imm64) &&
1169        isMask_64(Imm64)) {
1170      SDValue Val = N->getOperand(0);
1171      MB = 64 - CountTrailingOnes_64(Imm64);
1172      SH = 0;
1173
1174      // If the operand is a logical right shift, we can fold it into this
1175      // instruction: rldicl(rldicl(x, 64-n, n), 0, mb) -> rldicl(x, 64-n, mb)
1176      // for n <= mb. The right shift is really a left rotate followed by a
1177      // mask, and this mask is a more-restrictive sub-mask of the mask implied
1178      // by the shift.
1179      if (Val.getOpcode() == ISD::SRL &&
1180          isInt32Immediate(Val.getOperand(1).getNode(), Imm) && Imm <= MB) {
1181        assert(Imm < 64 && "Illegal shift amount");
1182        Val = Val.getOperand(0);
1183        SH = 64 - Imm;
1184      }
1185
1186      SDValue Ops[] = { Val, getI32Imm(SH), getI32Imm(MB) };
1187      return CurDAG->SelectNodeTo(N, PPC::RLDICL, MVT::i64, Ops);
1188    }
1189    // AND X, 0 -> 0, not "rlwinm 32".
1190    if (isInt32Immediate(N->getOperand(1), Imm) && (Imm == 0)) {
1191      ReplaceUses(SDValue(N, 0), N->getOperand(1));
1192      return nullptr;
1193    }
1194    // ISD::OR doesn't get all the bitfield insertion fun.
1195    // (and (or x, c1), c2) where isRunOfOnes(~(c1^c2)) is a bitfield insert
1196    if (isInt32Immediate(N->getOperand(1), Imm) &&
1197        N->getOperand(0).getOpcode() == ISD::OR &&
1198        isInt32Immediate(N->getOperand(0).getOperand(1), Imm2)) {
1199      unsigned MB, ME;
1200      Imm = ~(Imm^Imm2);
1201      if (isRunOfOnes(Imm, MB, ME)) {
1202        SDValue Ops[] = { N->getOperand(0).getOperand(0),
1203                            N->getOperand(0).getOperand(1),
1204                            getI32Imm(0), getI32Imm(MB),getI32Imm(ME) };
1205        return CurDAG->getMachineNode(PPC::RLWIMI, dl, MVT::i32, Ops);
1206      }
1207    }
1208
1209    // Other cases are autogenerated.
1210    break;
1211  }
1212  case ISD::OR:
1213    if (N->getValueType(0) == MVT::i32)
1214      if (SDNode *I = SelectBitfieldInsert(N))
1215        return I;
1216
1217    // Other cases are autogenerated.
1218    break;
1219  case ISD::SHL: {
1220    unsigned Imm, SH, MB, ME;
1221    if (isOpcWithIntImmediate(N->getOperand(0).getNode(), ISD::AND, Imm) &&
1222        isRotateAndMask(N, Imm, true, SH, MB, ME)) {
1223      SDValue Ops[] = { N->getOperand(0).getOperand(0),
1224                          getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) };
1225      return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
1226    }
1227
1228    // Other cases are autogenerated.
1229    break;
1230  }
1231  case ISD::SRL: {
1232    unsigned Imm, SH, MB, ME;
1233    if (isOpcWithIntImmediate(N->getOperand(0).getNode(), ISD::AND, Imm) &&
1234        isRotateAndMask(N, Imm, true, SH, MB, ME)) {
1235      SDValue Ops[] = { N->getOperand(0).getOperand(0),
1236                          getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) };
1237      return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops);
1238    }
1239
1240    // Other cases are autogenerated.
1241    break;
1242  }
1243  // FIXME: Remove this once the ANDI glue bug is fixed:
1244  case PPCISD::ANDIo_1_EQ_BIT:
1245  case PPCISD::ANDIo_1_GT_BIT: {
1246    if (!ANDIGlueBug)
1247      break;
1248
1249    EVT InVT = N->getOperand(0).getValueType();
1250    assert((InVT == MVT::i64 || InVT == MVT::i32) &&
1251           "Invalid input type for ANDIo_1_EQ_BIT");
1252
1253    unsigned Opcode = (InVT == MVT::i64) ? PPC::ANDIo8 : PPC::ANDIo;
1254    SDValue AndI(CurDAG->getMachineNode(Opcode, dl, InVT, MVT::Glue,
1255                                        N->getOperand(0),
1256                                        CurDAG->getTargetConstant(1, InVT)), 0);
1257    SDValue CR0Reg = CurDAG->getRegister(PPC::CR0, MVT::i32);
1258    SDValue SRIdxVal =
1259      CurDAG->getTargetConstant(N->getOpcode() == PPCISD::ANDIo_1_EQ_BIT ?
1260                                PPC::sub_eq : PPC::sub_gt, MVT::i32);
1261
1262    return CurDAG->SelectNodeTo(N, TargetOpcode::EXTRACT_SUBREG, MVT::i1,
1263                                CR0Reg, SRIdxVal,
1264                                SDValue(AndI.getNode(), 1) /* glue */);
1265  }
1266  case ISD::SELECT_CC: {
1267    ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(4))->get();
1268    EVT PtrVT = CurDAG->getTargetLoweringInfo().getPointerTy();
1269    bool isPPC64 = (PtrVT == MVT::i64);
1270
1271    // If this is a select of i1 operands, we'll pattern match it.
1272    if (PPCSubTarget->useCRBits() &&
1273        N->getOperand(0).getValueType() == MVT::i1)
1274      break;
1275
1276    // Handle the setcc cases here.  select_cc lhs, 0, 1, 0, cc
1277    if (!isPPC64)
1278      if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N->getOperand(1)))
1279        if (ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N->getOperand(2)))
1280          if (ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N->getOperand(3)))
1281            if (N1C->isNullValue() && N3C->isNullValue() &&
1282                N2C->getZExtValue() == 1ULL && CC == ISD::SETNE &&
1283                // FIXME: Implement this optzn for PPC64.
1284                N->getValueType(0) == MVT::i32) {
1285              SDNode *Tmp =
1286                CurDAG->getMachineNode(PPC::ADDIC, dl, MVT::i32, MVT::Glue,
1287                                       N->getOperand(0), getI32Imm(~0U));
1288              return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32,
1289                                          SDValue(Tmp, 0), N->getOperand(0),
1290                                          SDValue(Tmp, 1));
1291            }
1292
1293    SDValue CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC, dl);
1294
1295    if (N->getValueType(0) == MVT::i1) {
1296      // An i1 select is: (c & t) | (!c & f).
1297      bool Inv;
1298      unsigned Idx = getCRIdxForSetCC(CC, Inv);
1299
1300      unsigned SRI;
1301      switch (Idx) {
1302      default: llvm_unreachable("Invalid CC index");
1303      case 0: SRI = PPC::sub_lt; break;
1304      case 1: SRI = PPC::sub_gt; break;
1305      case 2: SRI = PPC::sub_eq; break;
1306      case 3: SRI = PPC::sub_un; break;
1307      }
1308
1309      SDValue CCBit = CurDAG->getTargetExtractSubreg(SRI, dl, MVT::i1, CCReg);
1310
1311      SDValue NotCCBit(CurDAG->getMachineNode(PPC::CRNOR, dl, MVT::i1,
1312                                              CCBit, CCBit), 0);
1313      SDValue C =    Inv ? NotCCBit : CCBit,
1314              NotC = Inv ? CCBit    : NotCCBit;
1315
1316      SDValue CAndT(CurDAG->getMachineNode(PPC::CRAND, dl, MVT::i1,
1317                                           C, N->getOperand(2)), 0);
1318      SDValue NotCAndF(CurDAG->getMachineNode(PPC::CRAND, dl, MVT::i1,
1319                                              NotC, N->getOperand(3)), 0);
1320
1321      return CurDAG->SelectNodeTo(N, PPC::CROR, MVT::i1, CAndT, NotCAndF);
1322    }
1323
1324    unsigned BROpc = getPredicateForSetCC(CC);
1325
1326    unsigned SelectCCOp;
1327    if (N->getValueType(0) == MVT::i32)
1328      SelectCCOp = PPC::SELECT_CC_I4;
1329    else if (N->getValueType(0) == MVT::i64)
1330      SelectCCOp = PPC::SELECT_CC_I8;
1331    else if (N->getValueType(0) == MVT::f32)
1332      SelectCCOp = PPC::SELECT_CC_F4;
1333    else if (N->getValueType(0) == MVT::f64)
1334      SelectCCOp = PPC::SELECT_CC_F8;
1335    else
1336      SelectCCOp = PPC::SELECT_CC_VRRC;
1337
1338    SDValue Ops[] = { CCReg, N->getOperand(2), N->getOperand(3),
1339                        getI32Imm(BROpc) };
1340    return CurDAG->SelectNodeTo(N, SelectCCOp, N->getValueType(0), Ops);
1341  }
1342  case ISD::VSELECT:
1343    if (PPCSubTarget->hasVSX()) {
1344      SDValue Ops[] = { N->getOperand(2), N->getOperand(1), N->getOperand(0) };
1345      return CurDAG->SelectNodeTo(N, PPC::XXSEL, N->getValueType(0), Ops);
1346    }
1347
1348    break;
1349  case ISD::VECTOR_SHUFFLE:
1350    if (PPCSubTarget->hasVSX() && (N->getValueType(0) == MVT::v2f64 ||
1351                                  N->getValueType(0) == MVT::v2i64)) {
1352      ShuffleVectorSDNode *SVN = cast<ShuffleVectorSDNode>(N);
1353
1354      SDValue Op1 = N->getOperand(SVN->getMaskElt(0) < 2 ? 0 : 1),
1355              Op2 = N->getOperand(SVN->getMaskElt(1) < 2 ? 0 : 1);
1356      unsigned DM[2];
1357
1358      for (int i = 0; i < 2; ++i)
1359        if (SVN->getMaskElt(i) <= 0 || SVN->getMaskElt(i) == 2)
1360          DM[i] = 0;
1361        else
1362          DM[i] = 1;
1363
1364      SDValue DMV = CurDAG->getTargetConstant(DM[1] | (DM[0] << 1), MVT::i32);
1365
1366      if (Op1 == Op2 && DM[0] == 0 && DM[1] == 0 &&
1367          Op1.getOpcode() == ISD::SCALAR_TO_VECTOR &&
1368          isa<LoadSDNode>(Op1.getOperand(0))) {
1369        LoadSDNode *LD = cast<LoadSDNode>(Op1.getOperand(0));
1370        SDValue Base, Offset;
1371
1372        if (LD->isUnindexed() &&
1373            SelectAddrIdxOnly(LD->getBasePtr(), Base, Offset)) {
1374          SDValue Chain = LD->getChain();
1375          SDValue Ops[] = { Base, Offset, Chain };
1376          return CurDAG->SelectNodeTo(N, PPC::LXVDSX,
1377                                      N->getValueType(0), Ops);
1378        }
1379      }
1380
1381      SDValue Ops[] = { Op1, Op2, DMV };
1382      return CurDAG->SelectNodeTo(N, PPC::XXPERMDI, N->getValueType(0), Ops);
1383    }
1384
1385    break;
1386  case PPCISD::BDNZ:
1387  case PPCISD::BDZ: {
1388    bool IsPPC64 = PPCSubTarget->isPPC64();
1389    SDValue Ops[] = { N->getOperand(1), N->getOperand(0) };
1390    return CurDAG->SelectNodeTo(N, N->getOpcode() == PPCISD::BDNZ ?
1391                                   (IsPPC64 ? PPC::BDNZ8 : PPC::BDNZ) :
1392                                   (IsPPC64 ? PPC::BDZ8 : PPC::BDZ),
1393                                MVT::Other, Ops);
1394  }
1395  case PPCISD::COND_BRANCH: {
1396    // Op #0 is the Chain.
1397    // Op #1 is the PPC::PRED_* number.
1398    // Op #2 is the CR#
1399    // Op #3 is the Dest MBB
1400    // Op #4 is the Flag.
1401    // Prevent PPC::PRED_* from being selected into LI.
1402    SDValue Pred =
1403      getI32Imm(cast<ConstantSDNode>(N->getOperand(1))->getZExtValue());
1404    SDValue Ops[] = { Pred, N->getOperand(2), N->getOperand(3),
1405      N->getOperand(0), N->getOperand(4) };
1406    return CurDAG->SelectNodeTo(N, PPC::BCC, MVT::Other, Ops);
1407  }
1408  case ISD::BR_CC: {
1409    ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(1))->get();
1410    unsigned PCC = getPredicateForSetCC(CC);
1411
1412    if (N->getOperand(2).getValueType() == MVT::i1) {
1413      unsigned Opc;
1414      bool Swap;
1415      switch (PCC) {
1416      default: llvm_unreachable("Unexpected Boolean-operand predicate");
1417      case PPC::PRED_LT: Opc = PPC::CRANDC; Swap = true;  break;
1418      case PPC::PRED_LE: Opc = PPC::CRORC;  Swap = true;  break;
1419      case PPC::PRED_EQ: Opc = PPC::CREQV;  Swap = false; break;
1420      case PPC::PRED_GE: Opc = PPC::CRORC;  Swap = false; break;
1421      case PPC::PRED_GT: Opc = PPC::CRANDC; Swap = false; break;
1422      case PPC::PRED_NE: Opc = PPC::CRXOR;  Swap = false; break;
1423      }
1424
1425      SDValue BitComp(CurDAG->getMachineNode(Opc, dl, MVT::i1,
1426                                             N->getOperand(Swap ? 3 : 2),
1427                                             N->getOperand(Swap ? 2 : 3)), 0);
1428      return CurDAG->SelectNodeTo(N, PPC::BC, MVT::Other,
1429                                  BitComp, N->getOperand(4), N->getOperand(0));
1430    }
1431
1432    SDValue CondCode = SelectCC(N->getOperand(2), N->getOperand(3), CC, dl);
1433    SDValue Ops[] = { getI32Imm(PCC), CondCode,
1434                        N->getOperand(4), N->getOperand(0) };
1435    return CurDAG->SelectNodeTo(N, PPC::BCC, MVT::Other, Ops);
1436  }
1437  case ISD::BRIND: {
1438    // FIXME: Should custom lower this.
1439    SDValue Chain = N->getOperand(0);
1440    SDValue Target = N->getOperand(1);
1441    unsigned Opc = Target.getValueType() == MVT::i32 ? PPC::MTCTR : PPC::MTCTR8;
1442    unsigned Reg = Target.getValueType() == MVT::i32 ? PPC::BCTR : PPC::BCTR8;
1443    Chain = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Glue, Target,
1444                                           Chain), 0);
1445    return CurDAG->SelectNodeTo(N, Reg, MVT::Other, Chain);
1446  }
1447  case PPCISD::TOC_ENTRY: {
1448    assert (PPCSubTarget->isPPC64() && "Only supported for 64-bit ABI");
1449
1450    // For medium and large code model, we generate two instructions as
1451    // described below.  Otherwise we allow SelectCodeCommon to handle this,
1452    // selecting one of LDtoc, LDtocJTI, and LDtocCPT.
1453    CodeModel::Model CModel = TM.getCodeModel();
1454    if (CModel != CodeModel::Medium && CModel != CodeModel::Large)
1455      break;
1456
1457    // The first source operand is a TargetGlobalAddress or a TargetJumpTable.
1458    // If it is an externally defined symbol, a symbol with common linkage,
1459    // a non-local function address, or a jump table address, or if we are
1460    // generating code for large code model, we generate:
1461    //   LDtocL(<ga:@sym>, ADDIStocHA(%X2, <ga:@sym>))
1462    // Otherwise we generate:
1463    //   ADDItocL(ADDIStocHA(%X2, <ga:@sym>), <ga:@sym>)
1464    SDValue GA = N->getOperand(0);
1465    SDValue TOCbase = N->getOperand(1);
1466    SDNode *Tmp = CurDAG->getMachineNode(PPC::ADDIStocHA, dl, MVT::i64,
1467                                        TOCbase, GA);
1468
1469    if (isa<JumpTableSDNode>(GA) || CModel == CodeModel::Large)
1470      return CurDAG->getMachineNode(PPC::LDtocL, dl, MVT::i64, GA,
1471                                    SDValue(Tmp, 0));
1472
1473    if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(GA)) {
1474      const GlobalValue *GValue = G->getGlobal();
1475      if ((GValue->getType()->getElementType()->isFunctionTy() &&
1476           (GValue->isDeclaration() || GValue->isWeakForLinker())) ||
1477          GValue->isDeclaration() || GValue->hasCommonLinkage() ||
1478          GValue->hasAvailableExternallyLinkage())
1479        return CurDAG->getMachineNode(PPC::LDtocL, dl, MVT::i64, GA,
1480                                      SDValue(Tmp, 0));
1481    }
1482
1483    return CurDAG->getMachineNode(PPC::ADDItocL, dl, MVT::i64,
1484                                  SDValue(Tmp, 0), GA);
1485  }
1486  case PPCISD::VADD_SPLAT: {
1487    // This expands into one of three sequences, depending on whether
1488    // the first operand is odd or even, positive or negative.
1489    assert(isa<ConstantSDNode>(N->getOperand(0)) &&
1490           isa<ConstantSDNode>(N->getOperand(1)) &&
1491           "Invalid operand on VADD_SPLAT!");
1492
1493    int Elt     = N->getConstantOperandVal(0);
1494    int EltSize = N->getConstantOperandVal(1);
1495    unsigned Opc1, Opc2, Opc3;
1496    EVT VT;
1497
1498    if (EltSize == 1) {
1499      Opc1 = PPC::VSPLTISB;
1500      Opc2 = PPC::VADDUBM;
1501      Opc3 = PPC::VSUBUBM;
1502      VT = MVT::v16i8;
1503    } else if (EltSize == 2) {
1504      Opc1 = PPC::VSPLTISH;
1505      Opc2 = PPC::VADDUHM;
1506      Opc3 = PPC::VSUBUHM;
1507      VT = MVT::v8i16;
1508    } else {
1509      assert(EltSize == 4 && "Invalid element size on VADD_SPLAT!");
1510      Opc1 = PPC::VSPLTISW;
1511      Opc2 = PPC::VADDUWM;
1512      Opc3 = PPC::VSUBUWM;
1513      VT = MVT::v4i32;
1514    }
1515
1516    if ((Elt & 1) == 0) {
1517      // Elt is even, in the range [-32,-18] + [16,30].
1518      //
1519      // Convert: VADD_SPLAT elt, size
1520      // Into:    tmp = VSPLTIS[BHW] elt
1521      //          VADDU[BHW]M tmp, tmp
1522      // Where:   [BHW] = B for size = 1, H for size = 2, W for size = 4
1523      SDValue EltVal = getI32Imm(Elt >> 1);
1524      SDNode *Tmp = CurDAG->getMachineNode(Opc1, dl, VT, EltVal);
1525      SDValue TmpVal = SDValue(Tmp, 0);
1526      return CurDAG->getMachineNode(Opc2, dl, VT, TmpVal, TmpVal);
1527
1528    } else if (Elt > 0) {
1529      // Elt is odd and positive, in the range [17,31].
1530      //
1531      // Convert: VADD_SPLAT elt, size
1532      // Into:    tmp1 = VSPLTIS[BHW] elt-16
1533      //          tmp2 = VSPLTIS[BHW] -16
1534      //          VSUBU[BHW]M tmp1, tmp2
1535      SDValue EltVal = getI32Imm(Elt - 16);
1536      SDNode *Tmp1 = CurDAG->getMachineNode(Opc1, dl, VT, EltVal);
1537      EltVal = getI32Imm(-16);
1538      SDNode *Tmp2 = CurDAG->getMachineNode(Opc1, dl, VT, EltVal);
1539      return CurDAG->getMachineNode(Opc3, dl, VT, SDValue(Tmp1, 0),
1540                                    SDValue(Tmp2, 0));
1541
1542    } else {
1543      // Elt is odd and negative, in the range [-31,-17].
1544      //
1545      // Convert: VADD_SPLAT elt, size
1546      // Into:    tmp1 = VSPLTIS[BHW] elt+16
1547      //          tmp2 = VSPLTIS[BHW] -16
1548      //          VADDU[BHW]M tmp1, tmp2
1549      SDValue EltVal = getI32Imm(Elt + 16);
1550      SDNode *Tmp1 = CurDAG->getMachineNode(Opc1, dl, VT, EltVal);
1551      EltVal = getI32Imm(-16);
1552      SDNode *Tmp2 = CurDAG->getMachineNode(Opc1, dl, VT, EltVal);
1553      return CurDAG->getMachineNode(Opc2, dl, VT, SDValue(Tmp1, 0),
1554                                    SDValue(Tmp2, 0));
1555    }
1556  }
1557  }
1558
1559  return SelectCode(N);
1560}
1561
1562/// PostprocessISelDAG - Perform some late peephole optimizations
1563/// on the DAG representation.
1564void PPCDAGToDAGISel::PostprocessISelDAG() {
1565
1566  // Skip peepholes at -O0.
1567  if (TM.getOptLevel() == CodeGenOpt::None)
1568    return;
1569
1570  PeepholePPC64();
1571  PeepholeCROps();
1572}
1573
1574// Check if all users of this node will become isel where the second operand
1575// is the constant zero. If this is so, and if we can negate the condition,
1576// then we can flip the true and false operands. This will allow the zero to
1577// be folded with the isel so that we don't need to materialize a register
1578// containing zero.
1579bool PPCDAGToDAGISel::AllUsersSelectZero(SDNode *N) {
1580  // If we're not using isel, then this does not matter.
1581  if (!PPCSubTarget->hasISEL())
1582    return false;
1583
1584  for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
1585       UI != UE; ++UI) {
1586    SDNode *User = *UI;
1587    if (!User->isMachineOpcode())
1588      return false;
1589    if (User->getMachineOpcode() != PPC::SELECT_I4 &&
1590        User->getMachineOpcode() != PPC::SELECT_I8)
1591      return false;
1592
1593    SDNode *Op2 = User->getOperand(2).getNode();
1594    if (!Op2->isMachineOpcode())
1595      return false;
1596
1597    if (Op2->getMachineOpcode() != PPC::LI &&
1598        Op2->getMachineOpcode() != PPC::LI8)
1599      return false;
1600
1601    ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op2->getOperand(0));
1602    if (!C)
1603      return false;
1604
1605    if (!C->isNullValue())
1606      return false;
1607  }
1608
1609  return true;
1610}
1611
1612void PPCDAGToDAGISel::SwapAllSelectUsers(SDNode *N) {
1613  SmallVector<SDNode *, 4> ToReplace;
1614  for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
1615       UI != UE; ++UI) {
1616    SDNode *User = *UI;
1617    assert((User->getMachineOpcode() == PPC::SELECT_I4 ||
1618            User->getMachineOpcode() == PPC::SELECT_I8) &&
1619           "Must have all select users");
1620    ToReplace.push_back(User);
1621  }
1622
1623  for (SmallVector<SDNode *, 4>::iterator UI = ToReplace.begin(),
1624       UE = ToReplace.end(); UI != UE; ++UI) {
1625    SDNode *User = *UI;
1626    SDNode *ResNode =
1627      CurDAG->getMachineNode(User->getMachineOpcode(), SDLoc(User),
1628                             User->getValueType(0), User->getOperand(0),
1629                             User->getOperand(2),
1630                             User->getOperand(1));
1631
1632      DEBUG(dbgs() << "CR Peephole replacing:\nOld:    ");
1633      DEBUG(User->dump(CurDAG));
1634      DEBUG(dbgs() << "\nNew: ");
1635      DEBUG(ResNode->dump(CurDAG));
1636      DEBUG(dbgs() << "\n");
1637
1638      ReplaceUses(User, ResNode);
1639  }
1640}
1641
1642void PPCDAGToDAGISel::PeepholeCROps() {
1643  bool IsModified;
1644  do {
1645    IsModified = false;
1646    for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(),
1647         E = CurDAG->allnodes_end(); I != E; ++I) {
1648      MachineSDNode *MachineNode = dyn_cast<MachineSDNode>(I);
1649      if (!MachineNode || MachineNode->use_empty())
1650        continue;
1651      SDNode *ResNode = MachineNode;
1652
1653      bool Op1Set   = false, Op1Unset = false,
1654           Op1Not   = false,
1655           Op2Set   = false, Op2Unset = false,
1656           Op2Not   = false;
1657
1658      unsigned Opcode = MachineNode->getMachineOpcode();
1659      switch (Opcode) {
1660      default: break;
1661      case PPC::CRAND:
1662      case PPC::CRNAND:
1663      case PPC::CROR:
1664      case PPC::CRXOR:
1665      case PPC::CRNOR:
1666      case PPC::CREQV:
1667      case PPC::CRANDC:
1668      case PPC::CRORC: {
1669        SDValue Op = MachineNode->getOperand(1);
1670        if (Op.isMachineOpcode()) {
1671          if (Op.getMachineOpcode() == PPC::CRSET)
1672            Op2Set = true;
1673          else if (Op.getMachineOpcode() == PPC::CRUNSET)
1674            Op2Unset = true;
1675          else if (Op.getMachineOpcode() == PPC::CRNOR &&
1676                   Op.getOperand(0) == Op.getOperand(1))
1677            Op2Not = true;
1678        }
1679        }  // fallthrough
1680      case PPC::BC:
1681      case PPC::BCn:
1682      case PPC::SELECT_I4:
1683      case PPC::SELECT_I8:
1684      case PPC::SELECT_F4:
1685      case PPC::SELECT_F8:
1686      case PPC::SELECT_VRRC: {
1687        SDValue Op = MachineNode->getOperand(0);
1688        if (Op.isMachineOpcode()) {
1689          if (Op.getMachineOpcode() == PPC::CRSET)
1690            Op1Set = true;
1691          else if (Op.getMachineOpcode() == PPC::CRUNSET)
1692            Op1Unset = true;
1693          else if (Op.getMachineOpcode() == PPC::CRNOR &&
1694                   Op.getOperand(0) == Op.getOperand(1))
1695            Op1Not = true;
1696        }
1697        }
1698        break;
1699      }
1700
1701      bool SelectSwap = false;
1702      switch (Opcode) {
1703      default: break;
1704      case PPC::CRAND:
1705        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1706          // x & x = x
1707          ResNode = MachineNode->getOperand(0).getNode();
1708        else if (Op1Set)
1709          // 1 & y = y
1710          ResNode = MachineNode->getOperand(1).getNode();
1711        else if (Op2Set)
1712          // x & 1 = x
1713          ResNode = MachineNode->getOperand(0).getNode();
1714        else if (Op1Unset || Op2Unset)
1715          // x & 0 = 0 & y = 0
1716          ResNode = CurDAG->getMachineNode(PPC::CRUNSET, SDLoc(MachineNode),
1717                                           MVT::i1);
1718        else if (Op1Not)
1719          // ~x & y = andc(y, x)
1720          ResNode = CurDAG->getMachineNode(PPC::CRANDC, SDLoc(MachineNode),
1721                                           MVT::i1, MachineNode->getOperand(1),
1722                                           MachineNode->getOperand(0).
1723                                             getOperand(0));
1724        else if (Op2Not)
1725          // x & ~y = andc(x, y)
1726          ResNode = CurDAG->getMachineNode(PPC::CRANDC, SDLoc(MachineNode),
1727                                           MVT::i1, MachineNode->getOperand(0),
1728                                           MachineNode->getOperand(1).
1729                                             getOperand(0));
1730        else if (AllUsersSelectZero(MachineNode))
1731          ResNode = CurDAG->getMachineNode(PPC::CRNAND, SDLoc(MachineNode),
1732                                           MVT::i1, MachineNode->getOperand(0),
1733                                           MachineNode->getOperand(1)),
1734          SelectSwap = true;
1735        break;
1736      case PPC::CRNAND:
1737        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1738          // nand(x, x) -> nor(x, x)
1739          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1740                                           MVT::i1, MachineNode->getOperand(0),
1741                                           MachineNode->getOperand(0));
1742        else if (Op1Set)
1743          // nand(1, y) -> nor(y, y)
1744          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1745                                           MVT::i1, MachineNode->getOperand(1),
1746                                           MachineNode->getOperand(1));
1747        else if (Op2Set)
1748          // nand(x, 1) -> nor(x, x)
1749          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1750                                           MVT::i1, MachineNode->getOperand(0),
1751                                           MachineNode->getOperand(0));
1752        else if (Op1Unset || Op2Unset)
1753          // nand(x, 0) = nand(0, y) = 1
1754          ResNode = CurDAG->getMachineNode(PPC::CRSET, SDLoc(MachineNode),
1755                                           MVT::i1);
1756        else if (Op1Not)
1757          // nand(~x, y) = ~(~x & y) = x | ~y = orc(x, y)
1758          ResNode = CurDAG->getMachineNode(PPC::CRORC, SDLoc(MachineNode),
1759                                           MVT::i1, MachineNode->getOperand(0).
1760                                                      getOperand(0),
1761                                           MachineNode->getOperand(1));
1762        else if (Op2Not)
1763          // nand(x, ~y) = ~x | y = orc(y, x)
1764          ResNode = CurDAG->getMachineNode(PPC::CRORC, SDLoc(MachineNode),
1765                                           MVT::i1, MachineNode->getOperand(1).
1766                                                      getOperand(0),
1767                                           MachineNode->getOperand(0));
1768        else if (AllUsersSelectZero(MachineNode))
1769          ResNode = CurDAG->getMachineNode(PPC::CRAND, SDLoc(MachineNode),
1770                                           MVT::i1, MachineNode->getOperand(0),
1771                                           MachineNode->getOperand(1)),
1772          SelectSwap = true;
1773        break;
1774      case PPC::CROR:
1775        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1776          // x | x = x
1777          ResNode = MachineNode->getOperand(0).getNode();
1778        else if (Op1Set || Op2Set)
1779          // x | 1 = 1 | y = 1
1780          ResNode = CurDAG->getMachineNode(PPC::CRSET, SDLoc(MachineNode),
1781                                           MVT::i1);
1782        else if (Op1Unset)
1783          // 0 | y = y
1784          ResNode = MachineNode->getOperand(1).getNode();
1785        else if (Op2Unset)
1786          // x | 0 = x
1787          ResNode = MachineNode->getOperand(0).getNode();
1788        else if (Op1Not)
1789          // ~x | y = orc(y, x)
1790          ResNode = CurDAG->getMachineNode(PPC::CRORC, SDLoc(MachineNode),
1791                                           MVT::i1, MachineNode->getOperand(1),
1792                                           MachineNode->getOperand(0).
1793                                             getOperand(0));
1794        else if (Op2Not)
1795          // x | ~y = orc(x, y)
1796          ResNode = CurDAG->getMachineNode(PPC::CRORC, SDLoc(MachineNode),
1797                                           MVT::i1, MachineNode->getOperand(0),
1798                                           MachineNode->getOperand(1).
1799                                             getOperand(0));
1800        else if (AllUsersSelectZero(MachineNode))
1801          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1802                                           MVT::i1, MachineNode->getOperand(0),
1803                                           MachineNode->getOperand(1)),
1804          SelectSwap = true;
1805        break;
1806      case PPC::CRXOR:
1807        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1808          // xor(x, x) = 0
1809          ResNode = CurDAG->getMachineNode(PPC::CRUNSET, SDLoc(MachineNode),
1810                                           MVT::i1);
1811        else if (Op1Set)
1812          // xor(1, y) -> nor(y, y)
1813          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1814                                           MVT::i1, MachineNode->getOperand(1),
1815                                           MachineNode->getOperand(1));
1816        else if (Op2Set)
1817          // xor(x, 1) -> nor(x, x)
1818          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1819                                           MVT::i1, MachineNode->getOperand(0),
1820                                           MachineNode->getOperand(0));
1821        else if (Op1Unset)
1822          // xor(0, y) = y
1823          ResNode = MachineNode->getOperand(1).getNode();
1824        else if (Op2Unset)
1825          // xor(x, 0) = x
1826          ResNode = MachineNode->getOperand(0).getNode();
1827        else if (Op1Not)
1828          // xor(~x, y) = eqv(x, y)
1829          ResNode = CurDAG->getMachineNode(PPC::CREQV, SDLoc(MachineNode),
1830                                           MVT::i1, MachineNode->getOperand(0).
1831                                                      getOperand(0),
1832                                           MachineNode->getOperand(1));
1833        else if (Op2Not)
1834          // xor(x, ~y) = eqv(x, y)
1835          ResNode = CurDAG->getMachineNode(PPC::CREQV, SDLoc(MachineNode),
1836                                           MVT::i1, MachineNode->getOperand(0),
1837                                           MachineNode->getOperand(1).
1838                                             getOperand(0));
1839        else if (AllUsersSelectZero(MachineNode))
1840          ResNode = CurDAG->getMachineNode(PPC::CREQV, SDLoc(MachineNode),
1841                                           MVT::i1, MachineNode->getOperand(0),
1842                                           MachineNode->getOperand(1)),
1843          SelectSwap = true;
1844        break;
1845      case PPC::CRNOR:
1846        if (Op1Set || Op2Set)
1847          // nor(1, y) -> 0
1848          ResNode = CurDAG->getMachineNode(PPC::CRUNSET, SDLoc(MachineNode),
1849                                           MVT::i1);
1850        else if (Op1Unset)
1851          // nor(0, y) = ~y -> nor(y, y)
1852          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1853                                           MVT::i1, MachineNode->getOperand(1),
1854                                           MachineNode->getOperand(1));
1855        else if (Op2Unset)
1856          // nor(x, 0) = ~x
1857          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1858                                           MVT::i1, MachineNode->getOperand(0),
1859                                           MachineNode->getOperand(0));
1860        else if (Op1Not)
1861          // nor(~x, y) = andc(x, y)
1862          ResNode = CurDAG->getMachineNode(PPC::CRANDC, SDLoc(MachineNode),
1863                                           MVT::i1, MachineNode->getOperand(0).
1864                                                      getOperand(0),
1865                                           MachineNode->getOperand(1));
1866        else if (Op2Not)
1867          // nor(x, ~y) = andc(y, x)
1868          ResNode = CurDAG->getMachineNode(PPC::CRANDC, SDLoc(MachineNode),
1869                                           MVT::i1, MachineNode->getOperand(1).
1870                                                      getOperand(0),
1871                                           MachineNode->getOperand(0));
1872        else if (AllUsersSelectZero(MachineNode))
1873          ResNode = CurDAG->getMachineNode(PPC::CROR, SDLoc(MachineNode),
1874                                           MVT::i1, MachineNode->getOperand(0),
1875                                           MachineNode->getOperand(1)),
1876          SelectSwap = true;
1877        break;
1878      case PPC::CREQV:
1879        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1880          // eqv(x, x) = 1
1881          ResNode = CurDAG->getMachineNode(PPC::CRSET, SDLoc(MachineNode),
1882                                           MVT::i1);
1883        else if (Op1Set)
1884          // eqv(1, y) = y
1885          ResNode = MachineNode->getOperand(1).getNode();
1886        else if (Op2Set)
1887          // eqv(x, 1) = x
1888          ResNode = MachineNode->getOperand(0).getNode();
1889        else if (Op1Unset)
1890          // eqv(0, y) = ~y -> nor(y, y)
1891          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1892                                           MVT::i1, MachineNode->getOperand(1),
1893                                           MachineNode->getOperand(1));
1894        else if (Op2Unset)
1895          // eqv(x, 0) = ~x
1896          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1897                                           MVT::i1, MachineNode->getOperand(0),
1898                                           MachineNode->getOperand(0));
1899        else if (Op1Not)
1900          // eqv(~x, y) = xor(x, y)
1901          ResNode = CurDAG->getMachineNode(PPC::CRXOR, SDLoc(MachineNode),
1902                                           MVT::i1, MachineNode->getOperand(0).
1903                                                      getOperand(0),
1904                                           MachineNode->getOperand(1));
1905        else if (Op2Not)
1906          // eqv(x, ~y) = xor(x, y)
1907          ResNode = CurDAG->getMachineNode(PPC::CRXOR, SDLoc(MachineNode),
1908                                           MVT::i1, MachineNode->getOperand(0),
1909                                           MachineNode->getOperand(1).
1910                                             getOperand(0));
1911        else if (AllUsersSelectZero(MachineNode))
1912          ResNode = CurDAG->getMachineNode(PPC::CRXOR, SDLoc(MachineNode),
1913                                           MVT::i1, MachineNode->getOperand(0),
1914                                           MachineNode->getOperand(1)),
1915          SelectSwap = true;
1916        break;
1917      case PPC::CRANDC:
1918        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1919          // andc(x, x) = 0
1920          ResNode = CurDAG->getMachineNode(PPC::CRUNSET, SDLoc(MachineNode),
1921                                           MVT::i1);
1922        else if (Op1Set)
1923          // andc(1, y) = ~y
1924          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1925                                           MVT::i1, MachineNode->getOperand(1),
1926                                           MachineNode->getOperand(1));
1927        else if (Op1Unset || Op2Set)
1928          // andc(0, y) = andc(x, 1) = 0
1929          ResNode = CurDAG->getMachineNode(PPC::CRUNSET, SDLoc(MachineNode),
1930                                           MVT::i1);
1931        else if (Op2Unset)
1932          // andc(x, 0) = x
1933          ResNode = MachineNode->getOperand(0).getNode();
1934        else if (Op1Not)
1935          // andc(~x, y) = ~(x | y) = nor(x, y)
1936          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1937                                           MVT::i1, MachineNode->getOperand(0).
1938                                                      getOperand(0),
1939                                           MachineNode->getOperand(1));
1940        else if (Op2Not)
1941          // andc(x, ~y) = x & y
1942          ResNode = CurDAG->getMachineNode(PPC::CRAND, SDLoc(MachineNode),
1943                                           MVT::i1, MachineNode->getOperand(0),
1944                                           MachineNode->getOperand(1).
1945                                             getOperand(0));
1946        else if (AllUsersSelectZero(MachineNode))
1947          ResNode = CurDAG->getMachineNode(PPC::CRORC, SDLoc(MachineNode),
1948                                           MVT::i1, MachineNode->getOperand(1),
1949                                           MachineNode->getOperand(0)),
1950          SelectSwap = true;
1951        break;
1952      case PPC::CRORC:
1953        if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
1954          // orc(x, x) = 1
1955          ResNode = CurDAG->getMachineNode(PPC::CRSET, SDLoc(MachineNode),
1956                                           MVT::i1);
1957        else if (Op1Set || Op2Unset)
1958          // orc(1, y) = orc(x, 0) = 1
1959          ResNode = CurDAG->getMachineNode(PPC::CRSET, SDLoc(MachineNode),
1960                                           MVT::i1);
1961        else if (Op2Set)
1962          // orc(x, 1) = x
1963          ResNode = MachineNode->getOperand(0).getNode();
1964        else if (Op1Unset)
1965          // orc(0, y) = ~y
1966          ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
1967                                           MVT::i1, MachineNode->getOperand(1),
1968                                           MachineNode->getOperand(1));
1969        else if (Op1Not)
1970          // orc(~x, y) = ~(x & y) = nand(x, y)
1971          ResNode = CurDAG->getMachineNode(PPC::CRNAND, SDLoc(MachineNode),
1972                                           MVT::i1, MachineNode->getOperand(0).
1973                                                      getOperand(0),
1974                                           MachineNode->getOperand(1));
1975        else if (Op2Not)
1976          // orc(x, ~y) = x | y
1977          ResNode = CurDAG->getMachineNode(PPC::CROR, SDLoc(MachineNode),
1978                                           MVT::i1, MachineNode->getOperand(0),
1979                                           MachineNode->getOperand(1).
1980                                             getOperand(0));
1981        else if (AllUsersSelectZero(MachineNode))
1982          ResNode = CurDAG->getMachineNode(PPC::CRANDC, SDLoc(MachineNode),
1983                                           MVT::i1, MachineNode->getOperand(1),
1984                                           MachineNode->getOperand(0)),
1985          SelectSwap = true;
1986        break;
1987      case PPC::SELECT_I4:
1988      case PPC::SELECT_I8:
1989      case PPC::SELECT_F4:
1990      case PPC::SELECT_F8:
1991      case PPC::SELECT_VRRC:
1992        if (Op1Set)
1993          ResNode = MachineNode->getOperand(1).getNode();
1994        else if (Op1Unset)
1995          ResNode = MachineNode->getOperand(2).getNode();
1996        else if (Op1Not)
1997          ResNode = CurDAG->getMachineNode(MachineNode->getMachineOpcode(),
1998                                           SDLoc(MachineNode),
1999                                           MachineNode->getValueType(0),
2000                                           MachineNode->getOperand(0).
2001                                             getOperand(0),
2002                                           MachineNode->getOperand(2),
2003                                           MachineNode->getOperand(1));
2004        break;
2005      case PPC::BC:
2006      case PPC::BCn:
2007        if (Op1Not)
2008          ResNode = CurDAG->getMachineNode(Opcode == PPC::BC ? PPC::BCn :
2009                                                               PPC::BC,
2010                                           SDLoc(MachineNode),
2011                                           MVT::Other,
2012                                           MachineNode->getOperand(0).
2013                                             getOperand(0),
2014                                           MachineNode->getOperand(1),
2015                                           MachineNode->getOperand(2));
2016        // FIXME: Handle Op1Set, Op1Unset here too.
2017        break;
2018      }
2019
2020      // If we're inverting this node because it is used only by selects that
2021      // we'd like to swap, then swap the selects before the node replacement.
2022      if (SelectSwap)
2023        SwapAllSelectUsers(MachineNode);
2024
2025      if (ResNode != MachineNode) {
2026        DEBUG(dbgs() << "CR Peephole replacing:\nOld:    ");
2027        DEBUG(MachineNode->dump(CurDAG));
2028        DEBUG(dbgs() << "\nNew: ");
2029        DEBUG(ResNode->dump(CurDAG));
2030        DEBUG(dbgs() << "\n");
2031
2032        ReplaceUses(MachineNode, ResNode);
2033        IsModified = true;
2034      }
2035    }
2036    if (IsModified)
2037      CurDAG->RemoveDeadNodes();
2038  } while (IsModified);
2039}
2040
2041void PPCDAGToDAGISel::PeepholePPC64() {
2042  // These optimizations are currently supported only for 64-bit SVR4.
2043  if (PPCSubTarget->isDarwin() || !PPCSubTarget->isPPC64())
2044    return;
2045
2046  SelectionDAG::allnodes_iterator Position(CurDAG->getRoot().getNode());
2047  ++Position;
2048
2049  while (Position != CurDAG->allnodes_begin()) {
2050    SDNode *N = --Position;
2051    // Skip dead nodes and any non-machine opcodes.
2052    if (N->use_empty() || !N->isMachineOpcode())
2053      continue;
2054
2055    unsigned FirstOp;
2056    unsigned StorageOpcode = N->getMachineOpcode();
2057
2058    switch (StorageOpcode) {
2059    default: continue;
2060
2061    case PPC::LBZ:
2062    case PPC::LBZ8:
2063    case PPC::LD:
2064    case PPC::LFD:
2065    case PPC::LFS:
2066    case PPC::LHA:
2067    case PPC::LHA8:
2068    case PPC::LHZ:
2069    case PPC::LHZ8:
2070    case PPC::LWA:
2071    case PPC::LWZ:
2072    case PPC::LWZ8:
2073      FirstOp = 0;
2074      break;
2075
2076    case PPC::STB:
2077    case PPC::STB8:
2078    case PPC::STD:
2079    case PPC::STFD:
2080    case PPC::STFS:
2081    case PPC::STH:
2082    case PPC::STH8:
2083    case PPC::STW:
2084    case PPC::STW8:
2085      FirstOp = 1;
2086      break;
2087    }
2088
2089    // If this is a load or store with a zero offset, we may be able to
2090    // fold an add-immediate into the memory operation.
2091    if (!isa<ConstantSDNode>(N->getOperand(FirstOp)) ||
2092        N->getConstantOperandVal(FirstOp) != 0)
2093      continue;
2094
2095    SDValue Base = N->getOperand(FirstOp + 1);
2096    if (!Base.isMachineOpcode())
2097      continue;
2098
2099    unsigned Flags = 0;
2100    bool ReplaceFlags = true;
2101
2102    // When the feeding operation is an add-immediate of some sort,
2103    // determine whether we need to add relocation information to the
2104    // target flags on the immediate operand when we fold it into the
2105    // load instruction.
2106    //
2107    // For something like ADDItocL, the relocation information is
2108    // inferred from the opcode; when we process it in the AsmPrinter,
2109    // we add the necessary relocation there.  A load, though, can receive
2110    // relocation from various flavors of ADDIxxx, so we need to carry
2111    // the relocation information in the target flags.
2112    switch (Base.getMachineOpcode()) {
2113    default: continue;
2114
2115    case PPC::ADDI8:
2116    case PPC::ADDI:
2117      // In some cases (such as TLS) the relocation information
2118      // is already in place on the operand, so copying the operand
2119      // is sufficient.
2120      ReplaceFlags = false;
2121      // For these cases, the immediate may not be divisible by 4, in
2122      // which case the fold is illegal for DS-form instructions.  (The
2123      // other cases provide aligned addresses and are always safe.)
2124      if ((StorageOpcode == PPC::LWA ||
2125           StorageOpcode == PPC::LD  ||
2126           StorageOpcode == PPC::STD) &&
2127          (!isa<ConstantSDNode>(Base.getOperand(1)) ||
2128           Base.getConstantOperandVal(1) % 4 != 0))
2129        continue;
2130      break;
2131    case PPC::ADDIdtprelL:
2132      Flags = PPCII::MO_DTPREL_LO;
2133      break;
2134    case PPC::ADDItlsldL:
2135      Flags = PPCII::MO_TLSLD_LO;
2136      break;
2137    case PPC::ADDItocL:
2138      Flags = PPCII::MO_TOC_LO;
2139      break;
2140    }
2141
2142    // We found an opportunity.  Reverse the operands from the add
2143    // immediate and substitute them into the load or store.  If
2144    // needed, update the target flags for the immediate operand to
2145    // reflect the necessary relocation information.
2146    DEBUG(dbgs() << "Folding add-immediate into mem-op:\nBase:    ");
2147    DEBUG(Base->dump(CurDAG));
2148    DEBUG(dbgs() << "\nN: ");
2149    DEBUG(N->dump(CurDAG));
2150    DEBUG(dbgs() << "\n");
2151
2152    SDValue ImmOpnd = Base.getOperand(1);
2153
2154    // If the relocation information isn't already present on the
2155    // immediate operand, add it now.
2156    if (ReplaceFlags) {
2157      if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(ImmOpnd)) {
2158        SDLoc dl(GA);
2159        const GlobalValue *GV = GA->getGlobal();
2160        // We can't perform this optimization for data whose alignment
2161        // is insufficient for the instruction encoding.
2162        if (GV->getAlignment() < 4 &&
2163            (StorageOpcode == PPC::LD || StorageOpcode == PPC::STD ||
2164             StorageOpcode == PPC::LWA)) {
2165          DEBUG(dbgs() << "Rejected this candidate for alignment.\n\n");
2166          continue;
2167        }
2168        ImmOpnd = CurDAG->getTargetGlobalAddress(GV, dl, MVT::i64, 0, Flags);
2169      } else if (ConstantPoolSDNode *CP =
2170                 dyn_cast<ConstantPoolSDNode>(ImmOpnd)) {
2171        const Constant *C = CP->getConstVal();
2172        ImmOpnd = CurDAG->getTargetConstantPool(C, MVT::i64,
2173                                                CP->getAlignment(),
2174                                                0, Flags);
2175      }
2176    }
2177
2178    if (FirstOp == 1) // Store
2179      (void)CurDAG->UpdateNodeOperands(N, N->getOperand(0), ImmOpnd,
2180                                       Base.getOperand(0), N->getOperand(3));
2181    else // Load
2182      (void)CurDAG->UpdateNodeOperands(N, ImmOpnd, Base.getOperand(0),
2183                                       N->getOperand(2));
2184
2185    // The add-immediate may now be dead, in which case remove it.
2186    if (Base.getNode()->use_empty())
2187      CurDAG->RemoveDeadNode(Base.getNode());
2188  }
2189}
2190
2191
2192/// createPPCISelDag - This pass converts a legalized DAG into a
2193/// PowerPC-specific DAG, ready for instruction scheduling.
2194///
2195FunctionPass *llvm::createPPCISelDag(PPCTargetMachine &TM) {
2196  return new PPCDAGToDAGISel(TM);
2197}
2198
2199static void initializePassOnce(PassRegistry &Registry) {
2200  const char *Name = "PowerPC DAG->DAG Pattern Instruction Selection";
2201  PassInfo *PI = new PassInfo(Name, "ppc-codegen", &SelectionDAGISel::ID,
2202                              nullptr, false, false);
2203  Registry.registerPass(*PI, true);
2204}
2205
2206void llvm::initializePPCDAGToDAGISelPass(PassRegistry &Registry) {
2207  CALL_ONCE_INITIALIZATION(initializePassOnce);
2208}
2209
2210