xref: /freebsd/contrib/llvm-project/llvm/lib/Target/SystemZ/SystemZInstrInfo.cpp (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1 //===-- SystemZInstrInfo.cpp - SystemZ instruction information ------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains the SystemZ implementation of the TargetInstrInfo class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "SystemZInstrInfo.h"
14 #include "MCTargetDesc/SystemZMCTargetDesc.h"
15 #include "SystemZ.h"
16 #include "SystemZInstrBuilder.h"
17 #include "SystemZSubtarget.h"
18 #include "llvm/ADT/Statistic.h"
19 #include "llvm/CodeGen/LiveInterval.h"
20 #include "llvm/CodeGen/LiveIntervals.h"
21 #include "llvm/CodeGen/LiveVariables.h"
22 #include "llvm/CodeGen/MachineBasicBlock.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineInstr.h"
26 #include "llvm/CodeGen/MachineMemOperand.h"
27 #include "llvm/CodeGen/MachineOperand.h"
28 #include "llvm/CodeGen/MachineRegisterInfo.h"
29 #include "llvm/CodeGen/SlotIndexes.h"
30 #include "llvm/CodeGen/TargetInstrInfo.h"
31 #include "llvm/CodeGen/TargetSubtargetInfo.h"
32 #include "llvm/MC/MCInstrDesc.h"
33 #include "llvm/MC/MCRegisterInfo.h"
34 #include "llvm/Support/BranchProbability.h"
35 #include "llvm/Support/ErrorHandling.h"
36 #include "llvm/Support/MathExtras.h"
37 #include "llvm/Target/TargetMachine.h"
38 #include <cassert>
39 #include <cstdint>
40 #include <iterator>
41 
42 using namespace llvm;
43 
44 #define GET_INSTRINFO_CTOR_DTOR
45 #define GET_INSTRMAP_INFO
46 #include "SystemZGenInstrInfo.inc"
47 
48 #define DEBUG_TYPE "systemz-II"
49 
50 // Return a mask with Count low bits set.
51 static uint64_t allOnes(unsigned int Count) {
52   return Count == 0 ? 0 : (uint64_t(1) << (Count - 1) << 1) - 1;
53 }
54 
55 // Pin the vtable to this file.
56 void SystemZInstrInfo::anchor() {}
57 
58 SystemZInstrInfo::SystemZInstrInfo(SystemZSubtarget &sti)
59   : SystemZGenInstrInfo(SystemZ::ADJCALLSTACKDOWN, SystemZ::ADJCALLSTACKUP),
60     RI(), STI(sti) {
61 }
62 
63 // MI is a 128-bit load or store.  Split it into two 64-bit loads or stores,
64 // each having the opcode given by NewOpcode.
65 void SystemZInstrInfo::splitMove(MachineBasicBlock::iterator MI,
66                                  unsigned NewOpcode) const {
67   MachineBasicBlock *MBB = MI->getParent();
68   MachineFunction &MF = *MBB->getParent();
69 
70   // Get two load or store instructions.  Use the original instruction for one
71   // of them (arbitrarily the second here) and create a clone for the other.
72   MachineInstr *EarlierMI = MF.CloneMachineInstr(&*MI);
73   MBB->insert(MI, EarlierMI);
74 
75   // Set up the two 64-bit registers and remember super reg and its flags.
76   MachineOperand &HighRegOp = EarlierMI->getOperand(0);
77   MachineOperand &LowRegOp = MI->getOperand(0);
78   Register Reg128 = LowRegOp.getReg();
79   unsigned Reg128Killed = getKillRegState(LowRegOp.isKill());
80   unsigned Reg128Undef  = getUndefRegState(LowRegOp.isUndef());
81   HighRegOp.setReg(RI.getSubReg(HighRegOp.getReg(), SystemZ::subreg_h64));
82   LowRegOp.setReg(RI.getSubReg(LowRegOp.getReg(), SystemZ::subreg_l64));
83 
84   if (MI->mayStore()) {
85     // Add implicit uses of the super register in case one of the subregs is
86     // undefined. We could track liveness and skip storing an undefined
87     // subreg, but this is hopefully rare (discovered with llvm-stress).
88     // If Reg128 was killed, set kill flag on MI.
89     unsigned Reg128UndefImpl = (Reg128Undef | RegState::Implicit);
90     MachineInstrBuilder(MF, EarlierMI).addReg(Reg128, Reg128UndefImpl);
91     MachineInstrBuilder(MF, MI).addReg(Reg128, (Reg128UndefImpl | Reg128Killed));
92   }
93 
94   // The address in the first (high) instruction is already correct.
95   // Adjust the offset in the second (low) instruction.
96   MachineOperand &HighOffsetOp = EarlierMI->getOperand(2);
97   MachineOperand &LowOffsetOp = MI->getOperand(2);
98   LowOffsetOp.setImm(LowOffsetOp.getImm() + 8);
99 
100   // Clear the kill flags on the registers in the first instruction.
101   if (EarlierMI->getOperand(0).isReg() && EarlierMI->getOperand(0).isUse())
102     EarlierMI->getOperand(0).setIsKill(false);
103   EarlierMI->getOperand(1).setIsKill(false);
104   EarlierMI->getOperand(3).setIsKill(false);
105 
106   // Set the opcodes.
107   unsigned HighOpcode = getOpcodeForOffset(NewOpcode, HighOffsetOp.getImm());
108   unsigned LowOpcode = getOpcodeForOffset(NewOpcode, LowOffsetOp.getImm());
109   assert(HighOpcode && LowOpcode && "Both offsets should be in range");
110 
111   EarlierMI->setDesc(get(HighOpcode));
112   MI->setDesc(get(LowOpcode));
113 }
114 
115 // Split ADJDYNALLOC instruction MI.
116 void SystemZInstrInfo::splitAdjDynAlloc(MachineBasicBlock::iterator MI) const {
117   MachineBasicBlock *MBB = MI->getParent();
118   MachineFunction &MF = *MBB->getParent();
119   MachineFrameInfo &MFFrame = MF.getFrameInfo();
120   MachineOperand &OffsetMO = MI->getOperand(2);
121 
122   uint64_t Offset = (MFFrame.getMaxCallFrameSize() +
123                      SystemZMC::CallFrameSize +
124                      OffsetMO.getImm());
125   unsigned NewOpcode = getOpcodeForOffset(SystemZ::LA, Offset);
126   assert(NewOpcode && "No support for huge argument lists yet");
127   MI->setDesc(get(NewOpcode));
128   OffsetMO.setImm(Offset);
129 }
130 
131 // MI is an RI-style pseudo instruction.  Replace it with LowOpcode
132 // if the first operand is a low GR32 and HighOpcode if the first operand
133 // is a high GR32.  ConvertHigh is true if LowOpcode takes a signed operand
134 // and HighOpcode takes an unsigned 32-bit operand.  In those cases,
135 // MI has the same kind of operand as LowOpcode, so needs to be converted
136 // if HighOpcode is used.
137 void SystemZInstrInfo::expandRIPseudo(MachineInstr &MI, unsigned LowOpcode,
138                                       unsigned HighOpcode,
139                                       bool ConvertHigh) const {
140   Register Reg = MI.getOperand(0).getReg();
141   bool IsHigh = SystemZ::isHighReg(Reg);
142   MI.setDesc(get(IsHigh ? HighOpcode : LowOpcode));
143   if (IsHigh && ConvertHigh)
144     MI.getOperand(1).setImm(uint32_t(MI.getOperand(1).getImm()));
145 }
146 
147 // MI is a three-operand RIE-style pseudo instruction.  Replace it with
148 // LowOpcodeK if the registers are both low GR32s, otherwise use a move
149 // followed by HighOpcode or LowOpcode, depending on whether the target
150 // is a high or low GR32.
151 void SystemZInstrInfo::expandRIEPseudo(MachineInstr &MI, unsigned LowOpcode,
152                                        unsigned LowOpcodeK,
153                                        unsigned HighOpcode) const {
154   Register DestReg = MI.getOperand(0).getReg();
155   Register SrcReg = MI.getOperand(1).getReg();
156   bool DestIsHigh = SystemZ::isHighReg(DestReg);
157   bool SrcIsHigh = SystemZ::isHighReg(SrcReg);
158   if (!DestIsHigh && !SrcIsHigh)
159     MI.setDesc(get(LowOpcodeK));
160   else {
161     if (DestReg != SrcReg) {
162       emitGRX32Move(*MI.getParent(), MI, MI.getDebugLoc(), DestReg, SrcReg,
163                     SystemZ::LR, 32, MI.getOperand(1).isKill(),
164                     MI.getOperand(1).isUndef());
165       MI.getOperand(1).setReg(DestReg);
166     }
167     MI.setDesc(get(DestIsHigh ? HighOpcode : LowOpcode));
168     MI.tieOperands(0, 1);
169   }
170 }
171 
172 // MI is an RXY-style pseudo instruction.  Replace it with LowOpcode
173 // if the first operand is a low GR32 and HighOpcode if the first operand
174 // is a high GR32.
175 void SystemZInstrInfo::expandRXYPseudo(MachineInstr &MI, unsigned LowOpcode,
176                                        unsigned HighOpcode) const {
177   Register Reg = MI.getOperand(0).getReg();
178   unsigned Opcode = getOpcodeForOffset(
179       SystemZ::isHighReg(Reg) ? HighOpcode : LowOpcode,
180       MI.getOperand(2).getImm());
181   MI.setDesc(get(Opcode));
182 }
183 
184 // MI is a load-on-condition pseudo instruction with a single register
185 // (source or destination) operand.  Replace it with LowOpcode if the
186 // register is a low GR32 and HighOpcode if the register is a high GR32.
187 void SystemZInstrInfo::expandLOCPseudo(MachineInstr &MI, unsigned LowOpcode,
188                                        unsigned HighOpcode) const {
189   Register Reg = MI.getOperand(0).getReg();
190   unsigned Opcode = SystemZ::isHighReg(Reg) ? HighOpcode : LowOpcode;
191   MI.setDesc(get(Opcode));
192 }
193 
194 // MI is an RR-style pseudo instruction that zero-extends the low Size bits
195 // of one GRX32 into another.  Replace it with LowOpcode if both operands
196 // are low registers, otherwise use RISB[LH]G.
197 void SystemZInstrInfo::expandZExtPseudo(MachineInstr &MI, unsigned LowOpcode,
198                                         unsigned Size) const {
199   MachineInstrBuilder MIB =
200     emitGRX32Move(*MI.getParent(), MI, MI.getDebugLoc(),
201                MI.getOperand(0).getReg(), MI.getOperand(1).getReg(), LowOpcode,
202                Size, MI.getOperand(1).isKill(), MI.getOperand(1).isUndef());
203 
204   // Keep the remaining operands as-is.
205   for (unsigned I = 2; I < MI.getNumOperands(); ++I)
206     MIB.add(MI.getOperand(I));
207 
208   MI.eraseFromParent();
209 }
210 
211 void SystemZInstrInfo::expandLoadStackGuard(MachineInstr *MI) const {
212   MachineBasicBlock *MBB = MI->getParent();
213   MachineFunction &MF = *MBB->getParent();
214   const Register Reg64 = MI->getOperand(0).getReg();
215   const Register Reg32 = RI.getSubReg(Reg64, SystemZ::subreg_l32);
216 
217   // EAR can only load the low subregister so us a shift for %a0 to produce
218   // the GR containing %a0 and %a1.
219 
220   // ear <reg>, %a0
221   BuildMI(*MBB, MI, MI->getDebugLoc(), get(SystemZ::EAR), Reg32)
222     .addReg(SystemZ::A0)
223     .addReg(Reg64, RegState::ImplicitDefine);
224 
225   // sllg <reg>, <reg>, 32
226   BuildMI(*MBB, MI, MI->getDebugLoc(), get(SystemZ::SLLG), Reg64)
227     .addReg(Reg64)
228     .addReg(0)
229     .addImm(32);
230 
231   // ear <reg>, %a1
232   BuildMI(*MBB, MI, MI->getDebugLoc(), get(SystemZ::EAR), Reg32)
233     .addReg(SystemZ::A1);
234 
235   // lg <reg>, 40(<reg>)
236   MI->setDesc(get(SystemZ::LG));
237   MachineInstrBuilder(MF, MI).addReg(Reg64).addImm(40).addReg(0);
238 }
239 
240 // Emit a zero-extending move from 32-bit GPR SrcReg to 32-bit GPR
241 // DestReg before MBBI in MBB.  Use LowLowOpcode when both DestReg and SrcReg
242 // are low registers, otherwise use RISB[LH]G.  Size is the number of bits
243 // taken from the low end of SrcReg (8 for LLCR, 16 for LLHR and 32 for LR).
244 // KillSrc is true if this move is the last use of SrcReg.
245 MachineInstrBuilder
246 SystemZInstrInfo::emitGRX32Move(MachineBasicBlock &MBB,
247                                 MachineBasicBlock::iterator MBBI,
248                                 const DebugLoc &DL, unsigned DestReg,
249                                 unsigned SrcReg, unsigned LowLowOpcode,
250                                 unsigned Size, bool KillSrc,
251                                 bool UndefSrc) const {
252   unsigned Opcode;
253   bool DestIsHigh = SystemZ::isHighReg(DestReg);
254   bool SrcIsHigh = SystemZ::isHighReg(SrcReg);
255   if (DestIsHigh && SrcIsHigh)
256     Opcode = SystemZ::RISBHH;
257   else if (DestIsHigh && !SrcIsHigh)
258     Opcode = SystemZ::RISBHL;
259   else if (!DestIsHigh && SrcIsHigh)
260     Opcode = SystemZ::RISBLH;
261   else {
262     return BuildMI(MBB, MBBI, DL, get(LowLowOpcode), DestReg)
263       .addReg(SrcReg, getKillRegState(KillSrc) | getUndefRegState(UndefSrc));
264   }
265   unsigned Rotate = (DestIsHigh != SrcIsHigh ? 32 : 0);
266   return BuildMI(MBB, MBBI, DL, get(Opcode), DestReg)
267     .addReg(DestReg, RegState::Undef)
268     .addReg(SrcReg, getKillRegState(KillSrc) | getUndefRegState(UndefSrc))
269     .addImm(32 - Size).addImm(128 + 31).addImm(Rotate);
270 }
271 
272 MachineInstr *SystemZInstrInfo::commuteInstructionImpl(MachineInstr &MI,
273                                                        bool NewMI,
274                                                        unsigned OpIdx1,
275                                                        unsigned OpIdx2) const {
276   auto cloneIfNew = [NewMI](MachineInstr &MI) -> MachineInstr & {
277     if (NewMI)
278       return *MI.getParent()->getParent()->CloneMachineInstr(&MI);
279     return MI;
280   };
281 
282   switch (MI.getOpcode()) {
283   case SystemZ::SELRMux:
284   case SystemZ::SELFHR:
285   case SystemZ::SELR:
286   case SystemZ::SELGR:
287   case SystemZ::LOCRMux:
288   case SystemZ::LOCFHR:
289   case SystemZ::LOCR:
290   case SystemZ::LOCGR: {
291     auto &WorkingMI = cloneIfNew(MI);
292     // Invert condition.
293     unsigned CCValid = WorkingMI.getOperand(3).getImm();
294     unsigned CCMask = WorkingMI.getOperand(4).getImm();
295     WorkingMI.getOperand(4).setImm(CCMask ^ CCValid);
296     return TargetInstrInfo::commuteInstructionImpl(WorkingMI, /*NewMI=*/false,
297                                                    OpIdx1, OpIdx2);
298   }
299   default:
300     return TargetInstrInfo::commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2);
301   }
302 }
303 
304 // If MI is a simple load or store for a frame object, return the register
305 // it loads or stores and set FrameIndex to the index of the frame object.
306 // Return 0 otherwise.
307 //
308 // Flag is SimpleBDXLoad for loads and SimpleBDXStore for stores.
309 static int isSimpleMove(const MachineInstr &MI, int &FrameIndex,
310                         unsigned Flag) {
311   const MCInstrDesc &MCID = MI.getDesc();
312   if ((MCID.TSFlags & Flag) && MI.getOperand(1).isFI() &&
313       MI.getOperand(2).getImm() == 0 && MI.getOperand(3).getReg() == 0) {
314     FrameIndex = MI.getOperand(1).getIndex();
315     return MI.getOperand(0).getReg();
316   }
317   return 0;
318 }
319 
320 unsigned SystemZInstrInfo::isLoadFromStackSlot(const MachineInstr &MI,
321                                                int &FrameIndex) const {
322   return isSimpleMove(MI, FrameIndex, SystemZII::SimpleBDXLoad);
323 }
324 
325 unsigned SystemZInstrInfo::isStoreToStackSlot(const MachineInstr &MI,
326                                               int &FrameIndex) const {
327   return isSimpleMove(MI, FrameIndex, SystemZII::SimpleBDXStore);
328 }
329 
330 bool SystemZInstrInfo::isStackSlotCopy(const MachineInstr &MI,
331                                        int &DestFrameIndex,
332                                        int &SrcFrameIndex) const {
333   // Check for MVC 0(Length,FI1),0(FI2)
334   const MachineFrameInfo &MFI = MI.getParent()->getParent()->getFrameInfo();
335   if (MI.getOpcode() != SystemZ::MVC || !MI.getOperand(0).isFI() ||
336       MI.getOperand(1).getImm() != 0 || !MI.getOperand(3).isFI() ||
337       MI.getOperand(4).getImm() != 0)
338     return false;
339 
340   // Check that Length covers the full slots.
341   int64_t Length = MI.getOperand(2).getImm();
342   unsigned FI1 = MI.getOperand(0).getIndex();
343   unsigned FI2 = MI.getOperand(3).getIndex();
344   if (MFI.getObjectSize(FI1) != Length ||
345       MFI.getObjectSize(FI2) != Length)
346     return false;
347 
348   DestFrameIndex = FI1;
349   SrcFrameIndex = FI2;
350   return true;
351 }
352 
353 bool SystemZInstrInfo::analyzeBranch(MachineBasicBlock &MBB,
354                                      MachineBasicBlock *&TBB,
355                                      MachineBasicBlock *&FBB,
356                                      SmallVectorImpl<MachineOperand> &Cond,
357                                      bool AllowModify) const {
358   // Most of the code and comments here are boilerplate.
359 
360   // Start from the bottom of the block and work up, examining the
361   // terminator instructions.
362   MachineBasicBlock::iterator I = MBB.end();
363   while (I != MBB.begin()) {
364     --I;
365     if (I->isDebugInstr())
366       continue;
367 
368     // Working from the bottom, when we see a non-terminator instruction, we're
369     // done.
370     if (!isUnpredicatedTerminator(*I))
371       break;
372 
373     // A terminator that isn't a branch can't easily be handled by this
374     // analysis.
375     if (!I->isBranch())
376       return true;
377 
378     // Can't handle indirect branches.
379     SystemZII::Branch Branch(getBranchInfo(*I));
380     if (!Branch.hasMBBTarget())
381       return true;
382 
383     // Punt on compound branches.
384     if (Branch.Type != SystemZII::BranchNormal)
385       return true;
386 
387     if (Branch.CCMask == SystemZ::CCMASK_ANY) {
388       // Handle unconditional branches.
389       if (!AllowModify) {
390         TBB = Branch.getMBBTarget();
391         continue;
392       }
393 
394       // If the block has any instructions after a JMP, delete them.
395       while (std::next(I) != MBB.end())
396         std::next(I)->eraseFromParent();
397 
398       Cond.clear();
399       FBB = nullptr;
400 
401       // Delete the JMP if it's equivalent to a fall-through.
402       if (MBB.isLayoutSuccessor(Branch.getMBBTarget())) {
403         TBB = nullptr;
404         I->eraseFromParent();
405         I = MBB.end();
406         continue;
407       }
408 
409       // TBB is used to indicate the unconditinal destination.
410       TBB = Branch.getMBBTarget();
411       continue;
412     }
413 
414     // Working from the bottom, handle the first conditional branch.
415     if (Cond.empty()) {
416       // FIXME: add X86-style branch swap
417       FBB = TBB;
418       TBB = Branch.getMBBTarget();
419       Cond.push_back(MachineOperand::CreateImm(Branch.CCValid));
420       Cond.push_back(MachineOperand::CreateImm(Branch.CCMask));
421       continue;
422     }
423 
424     // Handle subsequent conditional branches.
425     assert(Cond.size() == 2 && TBB && "Should have seen a conditional branch");
426 
427     // Only handle the case where all conditional branches branch to the same
428     // destination.
429     if (TBB != Branch.getMBBTarget())
430       return true;
431 
432     // If the conditions are the same, we can leave them alone.
433     unsigned OldCCValid = Cond[0].getImm();
434     unsigned OldCCMask = Cond[1].getImm();
435     if (OldCCValid == Branch.CCValid && OldCCMask == Branch.CCMask)
436       continue;
437 
438     // FIXME: Try combining conditions like X86 does.  Should be easy on Z!
439     return false;
440   }
441 
442   return false;
443 }
444 
445 unsigned SystemZInstrInfo::removeBranch(MachineBasicBlock &MBB,
446                                         int *BytesRemoved) const {
447   assert(!BytesRemoved && "code size not handled");
448 
449   // Most of the code and comments here are boilerplate.
450   MachineBasicBlock::iterator I = MBB.end();
451   unsigned Count = 0;
452 
453   while (I != MBB.begin()) {
454     --I;
455     if (I->isDebugInstr())
456       continue;
457     if (!I->isBranch())
458       break;
459     if (!getBranchInfo(*I).hasMBBTarget())
460       break;
461     // Remove the branch.
462     I->eraseFromParent();
463     I = MBB.end();
464     ++Count;
465   }
466 
467   return Count;
468 }
469 
470 bool SystemZInstrInfo::
471 reverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const {
472   assert(Cond.size() == 2 && "Invalid condition");
473   Cond[1].setImm(Cond[1].getImm() ^ Cond[0].getImm());
474   return false;
475 }
476 
477 unsigned SystemZInstrInfo::insertBranch(MachineBasicBlock &MBB,
478                                         MachineBasicBlock *TBB,
479                                         MachineBasicBlock *FBB,
480                                         ArrayRef<MachineOperand> Cond,
481                                         const DebugLoc &DL,
482                                         int *BytesAdded) const {
483   // In this function we output 32-bit branches, which should always
484   // have enough range.  They can be shortened and relaxed by later code
485   // in the pipeline, if desired.
486 
487   // Shouldn't be a fall through.
488   assert(TBB && "insertBranch must not be told to insert a fallthrough");
489   assert((Cond.size() == 2 || Cond.size() == 0) &&
490          "SystemZ branch conditions have one component!");
491   assert(!BytesAdded && "code size not handled");
492 
493   if (Cond.empty()) {
494     // Unconditional branch?
495     assert(!FBB && "Unconditional branch with multiple successors!");
496     BuildMI(&MBB, DL, get(SystemZ::J)).addMBB(TBB);
497     return 1;
498   }
499 
500   // Conditional branch.
501   unsigned Count = 0;
502   unsigned CCValid = Cond[0].getImm();
503   unsigned CCMask = Cond[1].getImm();
504   BuildMI(&MBB, DL, get(SystemZ::BRC))
505     .addImm(CCValid).addImm(CCMask).addMBB(TBB);
506   ++Count;
507 
508   if (FBB) {
509     // Two-way Conditional branch. Insert the second branch.
510     BuildMI(&MBB, DL, get(SystemZ::J)).addMBB(FBB);
511     ++Count;
512   }
513   return Count;
514 }
515 
516 bool SystemZInstrInfo::analyzeCompare(const MachineInstr &MI, Register &SrcReg,
517                                       Register &SrcReg2, int &Mask,
518                                       int &Value) const {
519   assert(MI.isCompare() && "Caller should have checked for a comparison");
520 
521   if (MI.getNumExplicitOperands() == 2 && MI.getOperand(0).isReg() &&
522       MI.getOperand(1).isImm()) {
523     SrcReg = MI.getOperand(0).getReg();
524     SrcReg2 = 0;
525     Value = MI.getOperand(1).getImm();
526     Mask = ~0;
527     return true;
528   }
529 
530   return false;
531 }
532 
533 bool SystemZInstrInfo::canInsertSelect(const MachineBasicBlock &MBB,
534                                        ArrayRef<MachineOperand> Pred,
535                                        Register DstReg, Register TrueReg,
536                                        Register FalseReg, int &CondCycles,
537                                        int &TrueCycles,
538                                        int &FalseCycles) const {
539   // Not all subtargets have LOCR instructions.
540   if (!STI.hasLoadStoreOnCond())
541     return false;
542   if (Pred.size() != 2)
543     return false;
544 
545   // Check register classes.
546   const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
547   const TargetRegisterClass *RC =
548     RI.getCommonSubClass(MRI.getRegClass(TrueReg), MRI.getRegClass(FalseReg));
549   if (!RC)
550     return false;
551 
552   // We have LOCR instructions for 32 and 64 bit general purpose registers.
553   if ((STI.hasLoadStoreOnCond2() &&
554        SystemZ::GRX32BitRegClass.hasSubClassEq(RC)) ||
555       SystemZ::GR32BitRegClass.hasSubClassEq(RC) ||
556       SystemZ::GR64BitRegClass.hasSubClassEq(RC)) {
557     CondCycles = 2;
558     TrueCycles = 2;
559     FalseCycles = 2;
560     return true;
561   }
562 
563   // Can't do anything else.
564   return false;
565 }
566 
567 void SystemZInstrInfo::insertSelect(MachineBasicBlock &MBB,
568                                     MachineBasicBlock::iterator I,
569                                     const DebugLoc &DL, Register DstReg,
570                                     ArrayRef<MachineOperand> Pred,
571                                     Register TrueReg,
572                                     Register FalseReg) const {
573   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
574   const TargetRegisterClass *RC = MRI.getRegClass(DstReg);
575 
576   assert(Pred.size() == 2 && "Invalid condition");
577   unsigned CCValid = Pred[0].getImm();
578   unsigned CCMask = Pred[1].getImm();
579 
580   unsigned Opc;
581   if (SystemZ::GRX32BitRegClass.hasSubClassEq(RC)) {
582     if (STI.hasMiscellaneousExtensions3())
583       Opc = SystemZ::SELRMux;
584     else if (STI.hasLoadStoreOnCond2())
585       Opc = SystemZ::LOCRMux;
586     else {
587       Opc = SystemZ::LOCR;
588       MRI.constrainRegClass(DstReg, &SystemZ::GR32BitRegClass);
589       Register TReg = MRI.createVirtualRegister(&SystemZ::GR32BitRegClass);
590       Register FReg = MRI.createVirtualRegister(&SystemZ::GR32BitRegClass);
591       BuildMI(MBB, I, DL, get(TargetOpcode::COPY), TReg).addReg(TrueReg);
592       BuildMI(MBB, I, DL, get(TargetOpcode::COPY), FReg).addReg(FalseReg);
593       TrueReg = TReg;
594       FalseReg = FReg;
595     }
596   } else if (SystemZ::GR64BitRegClass.hasSubClassEq(RC)) {
597     if (STI.hasMiscellaneousExtensions3())
598       Opc = SystemZ::SELGR;
599     else
600       Opc = SystemZ::LOCGR;
601   } else
602     llvm_unreachable("Invalid register class");
603 
604   BuildMI(MBB, I, DL, get(Opc), DstReg)
605     .addReg(FalseReg).addReg(TrueReg)
606     .addImm(CCValid).addImm(CCMask);
607 }
608 
609 bool SystemZInstrInfo::FoldImmediate(MachineInstr &UseMI, MachineInstr &DefMI,
610                                      Register Reg,
611                                      MachineRegisterInfo *MRI) const {
612   unsigned DefOpc = DefMI.getOpcode();
613   if (DefOpc != SystemZ::LHIMux && DefOpc != SystemZ::LHI &&
614       DefOpc != SystemZ::LGHI)
615     return false;
616   if (DefMI.getOperand(0).getReg() != Reg)
617     return false;
618   int32_t ImmVal = (int32_t)DefMI.getOperand(1).getImm();
619 
620   unsigned UseOpc = UseMI.getOpcode();
621   unsigned NewUseOpc;
622   unsigned UseIdx;
623   int CommuteIdx = -1;
624   bool TieOps = false;
625   switch (UseOpc) {
626   case SystemZ::SELRMux:
627     TieOps = true;
628     LLVM_FALLTHROUGH;
629   case SystemZ::LOCRMux:
630     if (!STI.hasLoadStoreOnCond2())
631       return false;
632     NewUseOpc = SystemZ::LOCHIMux;
633     if (UseMI.getOperand(2).getReg() == Reg)
634       UseIdx = 2;
635     else if (UseMI.getOperand(1).getReg() == Reg)
636       UseIdx = 2, CommuteIdx = 1;
637     else
638       return false;
639     break;
640   case SystemZ::SELGR:
641     TieOps = true;
642     LLVM_FALLTHROUGH;
643   case SystemZ::LOCGR:
644     if (!STI.hasLoadStoreOnCond2())
645       return false;
646     NewUseOpc = SystemZ::LOCGHI;
647     if (UseMI.getOperand(2).getReg() == Reg)
648       UseIdx = 2;
649     else if (UseMI.getOperand(1).getReg() == Reg)
650       UseIdx = 2, CommuteIdx = 1;
651     else
652       return false;
653     break;
654   default:
655     return false;
656   }
657 
658   if (CommuteIdx != -1)
659     if (!commuteInstruction(UseMI, false, CommuteIdx, UseIdx))
660       return false;
661 
662   bool DeleteDef = MRI->hasOneNonDBGUse(Reg);
663   UseMI.setDesc(get(NewUseOpc));
664   if (TieOps)
665     UseMI.tieOperands(0, 1);
666   UseMI.getOperand(UseIdx).ChangeToImmediate(ImmVal);
667   if (DeleteDef)
668     DefMI.eraseFromParent();
669 
670   return true;
671 }
672 
673 bool SystemZInstrInfo::isPredicable(const MachineInstr &MI) const {
674   unsigned Opcode = MI.getOpcode();
675   if (Opcode == SystemZ::Return ||
676       Opcode == SystemZ::Trap ||
677       Opcode == SystemZ::CallJG ||
678       Opcode == SystemZ::CallBR)
679     return true;
680   return false;
681 }
682 
683 bool SystemZInstrInfo::
684 isProfitableToIfCvt(MachineBasicBlock &MBB,
685                     unsigned NumCycles, unsigned ExtraPredCycles,
686                     BranchProbability Probability) const {
687   // Avoid using conditional returns at the end of a loop (since then
688   // we'd need to emit an unconditional branch to the beginning anyway,
689   // making the loop body longer).  This doesn't apply for low-probability
690   // loops (eg. compare-and-swap retry), so just decide based on branch
691   // probability instead of looping structure.
692   // However, since Compare and Trap instructions cost the same as a regular
693   // Compare instruction, we should allow the if conversion to convert this
694   // into a Conditional Compare regardless of the branch probability.
695   if (MBB.getLastNonDebugInstr()->getOpcode() != SystemZ::Trap &&
696       MBB.succ_empty() && Probability < BranchProbability(1, 8))
697     return false;
698   // For now only convert single instructions.
699   return NumCycles == 1;
700 }
701 
702 bool SystemZInstrInfo::
703 isProfitableToIfCvt(MachineBasicBlock &TMBB,
704                     unsigned NumCyclesT, unsigned ExtraPredCyclesT,
705                     MachineBasicBlock &FMBB,
706                     unsigned NumCyclesF, unsigned ExtraPredCyclesF,
707                     BranchProbability Probability) const {
708   // For now avoid converting mutually-exclusive cases.
709   return false;
710 }
711 
712 bool SystemZInstrInfo::
713 isProfitableToDupForIfCvt(MachineBasicBlock &MBB, unsigned NumCycles,
714                           BranchProbability Probability) const {
715   // For now only duplicate single instructions.
716   return NumCycles == 1;
717 }
718 
719 bool SystemZInstrInfo::PredicateInstruction(
720     MachineInstr &MI, ArrayRef<MachineOperand> Pred) const {
721   assert(Pred.size() == 2 && "Invalid condition");
722   unsigned CCValid = Pred[0].getImm();
723   unsigned CCMask = Pred[1].getImm();
724   assert(CCMask > 0 && CCMask < 15 && "Invalid predicate");
725   unsigned Opcode = MI.getOpcode();
726   if (Opcode == SystemZ::Trap) {
727     MI.setDesc(get(SystemZ::CondTrap));
728     MachineInstrBuilder(*MI.getParent()->getParent(), MI)
729       .addImm(CCValid).addImm(CCMask)
730       .addReg(SystemZ::CC, RegState::Implicit);
731     return true;
732   }
733   if (Opcode == SystemZ::Return) {
734     MI.setDesc(get(SystemZ::CondReturn));
735     MachineInstrBuilder(*MI.getParent()->getParent(), MI)
736       .addImm(CCValid).addImm(CCMask)
737       .addReg(SystemZ::CC, RegState::Implicit);
738     return true;
739   }
740   if (Opcode == SystemZ::CallJG) {
741     MachineOperand FirstOp = MI.getOperand(0);
742     const uint32_t *RegMask = MI.getOperand(1).getRegMask();
743     MI.RemoveOperand(1);
744     MI.RemoveOperand(0);
745     MI.setDesc(get(SystemZ::CallBRCL));
746     MachineInstrBuilder(*MI.getParent()->getParent(), MI)
747         .addImm(CCValid)
748         .addImm(CCMask)
749         .add(FirstOp)
750         .addRegMask(RegMask)
751         .addReg(SystemZ::CC, RegState::Implicit);
752     return true;
753   }
754   if (Opcode == SystemZ::CallBR) {
755     const uint32_t *RegMask = MI.getOperand(0).getRegMask();
756     MI.RemoveOperand(0);
757     MI.setDesc(get(SystemZ::CallBCR));
758     MachineInstrBuilder(*MI.getParent()->getParent(), MI)
759       .addImm(CCValid).addImm(CCMask)
760       .addRegMask(RegMask)
761       .addReg(SystemZ::CC, RegState::Implicit);
762     return true;
763   }
764   return false;
765 }
766 
767 void SystemZInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
768                                    MachineBasicBlock::iterator MBBI,
769                                    const DebugLoc &DL, MCRegister DestReg,
770                                    MCRegister SrcReg, bool KillSrc) const {
771   // Split 128-bit GPR moves into two 64-bit moves. Add implicit uses of the
772   // super register in case one of the subregs is undefined.
773   // This handles ADDR128 too.
774   if (SystemZ::GR128BitRegClass.contains(DestReg, SrcReg)) {
775     copyPhysReg(MBB, MBBI, DL, RI.getSubReg(DestReg, SystemZ::subreg_h64),
776                 RI.getSubReg(SrcReg, SystemZ::subreg_h64), KillSrc);
777     MachineInstrBuilder(*MBB.getParent(), std::prev(MBBI))
778       .addReg(SrcReg, RegState::Implicit);
779     copyPhysReg(MBB, MBBI, DL, RI.getSubReg(DestReg, SystemZ::subreg_l64),
780                 RI.getSubReg(SrcReg, SystemZ::subreg_l64), KillSrc);
781     MachineInstrBuilder(*MBB.getParent(), std::prev(MBBI))
782       .addReg(SrcReg, (getKillRegState(KillSrc) | RegState::Implicit));
783     return;
784   }
785 
786   if (SystemZ::GRX32BitRegClass.contains(DestReg, SrcReg)) {
787     emitGRX32Move(MBB, MBBI, DL, DestReg, SrcReg, SystemZ::LR, 32, KillSrc,
788                   false);
789     return;
790   }
791 
792   // Move 128-bit floating-point values between VR128 and FP128.
793   if (SystemZ::VR128BitRegClass.contains(DestReg) &&
794       SystemZ::FP128BitRegClass.contains(SrcReg)) {
795     MCRegister SrcRegHi =
796         RI.getMatchingSuperReg(RI.getSubReg(SrcReg, SystemZ::subreg_h64),
797                                SystemZ::subreg_h64, &SystemZ::VR128BitRegClass);
798     MCRegister SrcRegLo =
799         RI.getMatchingSuperReg(RI.getSubReg(SrcReg, SystemZ::subreg_l64),
800                                SystemZ::subreg_h64, &SystemZ::VR128BitRegClass);
801 
802     BuildMI(MBB, MBBI, DL, get(SystemZ::VMRHG), DestReg)
803       .addReg(SrcRegHi, getKillRegState(KillSrc))
804       .addReg(SrcRegLo, getKillRegState(KillSrc));
805     return;
806   }
807   if (SystemZ::FP128BitRegClass.contains(DestReg) &&
808       SystemZ::VR128BitRegClass.contains(SrcReg)) {
809     MCRegister DestRegHi =
810         RI.getMatchingSuperReg(RI.getSubReg(DestReg, SystemZ::subreg_h64),
811                                SystemZ::subreg_h64, &SystemZ::VR128BitRegClass);
812     MCRegister DestRegLo =
813         RI.getMatchingSuperReg(RI.getSubReg(DestReg, SystemZ::subreg_l64),
814                                SystemZ::subreg_h64, &SystemZ::VR128BitRegClass);
815 
816     if (DestRegHi != SrcReg)
817       copyPhysReg(MBB, MBBI, DL, DestRegHi, SrcReg, false);
818     BuildMI(MBB, MBBI, DL, get(SystemZ::VREPG), DestRegLo)
819       .addReg(SrcReg, getKillRegState(KillSrc)).addImm(1);
820     return;
821   }
822 
823   // Move CC value from a GR32.
824   if (DestReg == SystemZ::CC) {
825     unsigned Opcode =
826       SystemZ::GR32BitRegClass.contains(SrcReg) ? SystemZ::TMLH : SystemZ::TMHH;
827     BuildMI(MBB, MBBI, DL, get(Opcode))
828       .addReg(SrcReg, getKillRegState(KillSrc))
829       .addImm(3 << (SystemZ::IPM_CC - 16));
830     return;
831   }
832 
833   // Everything else needs only one instruction.
834   unsigned Opcode;
835   if (SystemZ::GR64BitRegClass.contains(DestReg, SrcReg))
836     Opcode = SystemZ::LGR;
837   else if (SystemZ::FP32BitRegClass.contains(DestReg, SrcReg))
838     // For z13 we prefer LDR over LER to avoid partial register dependencies.
839     Opcode = STI.hasVector() ? SystemZ::LDR32 : SystemZ::LER;
840   else if (SystemZ::FP64BitRegClass.contains(DestReg, SrcReg))
841     Opcode = SystemZ::LDR;
842   else if (SystemZ::FP128BitRegClass.contains(DestReg, SrcReg))
843     Opcode = SystemZ::LXR;
844   else if (SystemZ::VR32BitRegClass.contains(DestReg, SrcReg))
845     Opcode = SystemZ::VLR32;
846   else if (SystemZ::VR64BitRegClass.contains(DestReg, SrcReg))
847     Opcode = SystemZ::VLR64;
848   else if (SystemZ::VR128BitRegClass.contains(DestReg, SrcReg))
849     Opcode = SystemZ::VLR;
850   else if (SystemZ::AR32BitRegClass.contains(DestReg, SrcReg))
851     Opcode = SystemZ::CPYA;
852   else
853     llvm_unreachable("Impossible reg-to-reg copy");
854 
855   BuildMI(MBB, MBBI, DL, get(Opcode), DestReg)
856     .addReg(SrcReg, getKillRegState(KillSrc));
857 }
858 
859 void SystemZInstrInfo::storeRegToStackSlot(
860     MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, Register SrcReg,
861     bool isKill, int FrameIdx, const TargetRegisterClass *RC,
862     const TargetRegisterInfo *TRI) const {
863   DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
864 
865   // Callers may expect a single instruction, so keep 128-bit moves
866   // together for now and lower them after register allocation.
867   unsigned LoadOpcode, StoreOpcode;
868   getLoadStoreOpcodes(RC, LoadOpcode, StoreOpcode);
869   addFrameReference(BuildMI(MBB, MBBI, DL, get(StoreOpcode))
870                         .addReg(SrcReg, getKillRegState(isKill)),
871                     FrameIdx);
872 }
873 
874 void SystemZInstrInfo::loadRegFromStackSlot(
875     MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, Register DestReg,
876     int FrameIdx, const TargetRegisterClass *RC,
877     const TargetRegisterInfo *TRI) const {
878   DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
879 
880   // Callers may expect a single instruction, so keep 128-bit moves
881   // together for now and lower them after register allocation.
882   unsigned LoadOpcode, StoreOpcode;
883   getLoadStoreOpcodes(RC, LoadOpcode, StoreOpcode);
884   addFrameReference(BuildMI(MBB, MBBI, DL, get(LoadOpcode), DestReg),
885                     FrameIdx);
886 }
887 
888 // Return true if MI is a simple load or store with a 12-bit displacement
889 // and no index.  Flag is SimpleBDXLoad for loads and SimpleBDXStore for stores.
890 static bool isSimpleBD12Move(const MachineInstr *MI, unsigned Flag) {
891   const MCInstrDesc &MCID = MI->getDesc();
892   return ((MCID.TSFlags & Flag) &&
893           isUInt<12>(MI->getOperand(2).getImm()) &&
894           MI->getOperand(3).getReg() == 0);
895 }
896 
897 namespace {
898 
899 struct LogicOp {
900   LogicOp() = default;
901   LogicOp(unsigned regSize, unsigned immLSB, unsigned immSize)
902     : RegSize(regSize), ImmLSB(immLSB), ImmSize(immSize) {}
903 
904   explicit operator bool() const { return RegSize; }
905 
906   unsigned RegSize = 0;
907   unsigned ImmLSB = 0;
908   unsigned ImmSize = 0;
909 };
910 
911 } // end anonymous namespace
912 
913 static LogicOp interpretAndImmediate(unsigned Opcode) {
914   switch (Opcode) {
915   case SystemZ::NILMux: return LogicOp(32,  0, 16);
916   case SystemZ::NIHMux: return LogicOp(32, 16, 16);
917   case SystemZ::NILL64: return LogicOp(64,  0, 16);
918   case SystemZ::NILH64: return LogicOp(64, 16, 16);
919   case SystemZ::NIHL64: return LogicOp(64, 32, 16);
920   case SystemZ::NIHH64: return LogicOp(64, 48, 16);
921   case SystemZ::NIFMux: return LogicOp(32,  0, 32);
922   case SystemZ::NILF64: return LogicOp(64,  0, 32);
923   case SystemZ::NIHF64: return LogicOp(64, 32, 32);
924   default:              return LogicOp();
925   }
926 }
927 
928 static void transferDeadCC(MachineInstr *OldMI, MachineInstr *NewMI) {
929   if (OldMI->registerDefIsDead(SystemZ::CC)) {
930     MachineOperand *CCDef = NewMI->findRegisterDefOperand(SystemZ::CC);
931     if (CCDef != nullptr)
932       CCDef->setIsDead(true);
933   }
934 }
935 
936 static void transferMIFlag(MachineInstr *OldMI, MachineInstr *NewMI,
937                            MachineInstr::MIFlag Flag) {
938   if (OldMI->getFlag(Flag))
939     NewMI->setFlag(Flag);
940 }
941 
942 MachineInstr *SystemZInstrInfo::convertToThreeAddress(
943     MachineFunction::iterator &MFI, MachineInstr &MI, LiveVariables *LV) const {
944   MachineBasicBlock *MBB = MI.getParent();
945 
946   // Try to convert an AND into an RISBG-type instruction.
947   // TODO: It might be beneficial to select RISBG and shorten to AND instead.
948   if (LogicOp And = interpretAndImmediate(MI.getOpcode())) {
949     uint64_t Imm = MI.getOperand(2).getImm() << And.ImmLSB;
950     // AND IMMEDIATE leaves the other bits of the register unchanged.
951     Imm |= allOnes(And.RegSize) & ~(allOnes(And.ImmSize) << And.ImmLSB);
952     unsigned Start, End;
953     if (isRxSBGMask(Imm, And.RegSize, Start, End)) {
954       unsigned NewOpcode;
955       if (And.RegSize == 64) {
956         NewOpcode = SystemZ::RISBG;
957         // Prefer RISBGN if available, since it does not clobber CC.
958         if (STI.hasMiscellaneousExtensions())
959           NewOpcode = SystemZ::RISBGN;
960       } else {
961         NewOpcode = SystemZ::RISBMux;
962         Start &= 31;
963         End &= 31;
964       }
965       MachineOperand &Dest = MI.getOperand(0);
966       MachineOperand &Src = MI.getOperand(1);
967       MachineInstrBuilder MIB =
968           BuildMI(*MBB, MI, MI.getDebugLoc(), get(NewOpcode))
969               .add(Dest)
970               .addReg(0)
971               .addReg(Src.getReg(), getKillRegState(Src.isKill()),
972                       Src.getSubReg())
973               .addImm(Start)
974               .addImm(End + 128)
975               .addImm(0);
976       if (LV) {
977         unsigned NumOps = MI.getNumOperands();
978         for (unsigned I = 1; I < NumOps; ++I) {
979           MachineOperand &Op = MI.getOperand(I);
980           if (Op.isReg() && Op.isKill())
981             LV->replaceKillInstruction(Op.getReg(), MI, *MIB);
982         }
983       }
984       transferDeadCC(&MI, MIB);
985       return MIB;
986     }
987   }
988   return nullptr;
989 }
990 
991 MachineInstr *SystemZInstrInfo::foldMemoryOperandImpl(
992     MachineFunction &MF, MachineInstr &MI, ArrayRef<unsigned> Ops,
993     MachineBasicBlock::iterator InsertPt, int FrameIndex,
994     LiveIntervals *LIS, VirtRegMap *VRM) const {
995   const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
996   MachineRegisterInfo &MRI = MF.getRegInfo();
997   const MachineFrameInfo &MFI = MF.getFrameInfo();
998   unsigned Size = MFI.getObjectSize(FrameIndex);
999   unsigned Opcode = MI.getOpcode();
1000 
1001   // Check CC liveness if new instruction introduces a dead def of CC.
1002   MCRegUnitIterator CCUnit(SystemZ::CC, TRI);
1003   SlotIndex MISlot = SlotIndex();
1004   LiveRange *CCLiveRange = nullptr;
1005   bool CCLiveAtMI = true;
1006   if (LIS) {
1007     MISlot = LIS->getSlotIndexes()->getInstructionIndex(MI).getRegSlot();
1008     CCLiveRange = &LIS->getRegUnit(*CCUnit);
1009     CCLiveAtMI = CCLiveRange->liveAt(MISlot);
1010   }
1011   ++CCUnit;
1012   assert(!CCUnit.isValid() && "CC only has one reg unit.");
1013 
1014   if (Ops.size() == 2 && Ops[0] == 0 && Ops[1] == 1) {
1015     if (!CCLiveAtMI && (Opcode == SystemZ::LA || Opcode == SystemZ::LAY) &&
1016         isInt<8>(MI.getOperand(2).getImm()) && !MI.getOperand(3).getReg()) {
1017       // LA(Y) %reg, CONST(%reg) -> AGSI %mem, CONST
1018       MachineInstr *BuiltMI = BuildMI(*InsertPt->getParent(), InsertPt,
1019                                       MI.getDebugLoc(), get(SystemZ::AGSI))
1020         .addFrameIndex(FrameIndex)
1021         .addImm(0)
1022         .addImm(MI.getOperand(2).getImm());
1023       BuiltMI->findRegisterDefOperand(SystemZ::CC)->setIsDead(true);
1024       CCLiveRange->createDeadDef(MISlot, LIS->getVNInfoAllocator());
1025       return BuiltMI;
1026     }
1027     return nullptr;
1028   }
1029 
1030   // All other cases require a single operand.
1031   if (Ops.size() != 1)
1032     return nullptr;
1033 
1034   unsigned OpNum = Ops[0];
1035   assert(Size * 8 ==
1036            TRI->getRegSizeInBits(*MF.getRegInfo()
1037                                .getRegClass(MI.getOperand(OpNum).getReg())) &&
1038          "Invalid size combination");
1039 
1040   if ((Opcode == SystemZ::AHI || Opcode == SystemZ::AGHI) && OpNum == 0 &&
1041       isInt<8>(MI.getOperand(2).getImm())) {
1042     // A(G)HI %reg, CONST -> A(G)SI %mem, CONST
1043     Opcode = (Opcode == SystemZ::AHI ? SystemZ::ASI : SystemZ::AGSI);
1044     MachineInstr *BuiltMI =
1045         BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(), get(Opcode))
1046             .addFrameIndex(FrameIndex)
1047             .addImm(0)
1048             .addImm(MI.getOperand(2).getImm());
1049     transferDeadCC(&MI, BuiltMI);
1050     transferMIFlag(&MI, BuiltMI, MachineInstr::NoSWrap);
1051     return BuiltMI;
1052   }
1053 
1054   if ((Opcode == SystemZ::ALFI && OpNum == 0 &&
1055        isInt<8>((int32_t)MI.getOperand(2).getImm())) ||
1056       (Opcode == SystemZ::ALGFI && OpNum == 0 &&
1057        isInt<8>((int64_t)MI.getOperand(2).getImm()))) {
1058     // AL(G)FI %reg, CONST -> AL(G)SI %mem, CONST
1059     Opcode = (Opcode == SystemZ::ALFI ? SystemZ::ALSI : SystemZ::ALGSI);
1060     MachineInstr *BuiltMI =
1061         BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(), get(Opcode))
1062             .addFrameIndex(FrameIndex)
1063             .addImm(0)
1064             .addImm((int8_t)MI.getOperand(2).getImm());
1065     transferDeadCC(&MI, BuiltMI);
1066     return BuiltMI;
1067   }
1068 
1069   if ((Opcode == SystemZ::SLFI && OpNum == 0 &&
1070        isInt<8>((int32_t)-MI.getOperand(2).getImm())) ||
1071       (Opcode == SystemZ::SLGFI && OpNum == 0 &&
1072        isInt<8>((int64_t)-MI.getOperand(2).getImm()))) {
1073     // SL(G)FI %reg, CONST -> AL(G)SI %mem, -CONST
1074     Opcode = (Opcode == SystemZ::SLFI ? SystemZ::ALSI : SystemZ::ALGSI);
1075     MachineInstr *BuiltMI =
1076         BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(), get(Opcode))
1077             .addFrameIndex(FrameIndex)
1078             .addImm(0)
1079             .addImm((int8_t)-MI.getOperand(2).getImm());
1080     transferDeadCC(&MI, BuiltMI);
1081     return BuiltMI;
1082   }
1083 
1084   unsigned MemImmOpc = 0;
1085   switch (Opcode) {
1086   case SystemZ::LHIMux:
1087   case SystemZ::LHI:    MemImmOpc = SystemZ::MVHI;  break;
1088   case SystemZ::LGHI:   MemImmOpc = SystemZ::MVGHI; break;
1089   case SystemZ::CHIMux:
1090   case SystemZ::CHI:    MemImmOpc = SystemZ::CHSI;  break;
1091   case SystemZ::CGHI:   MemImmOpc = SystemZ::CGHSI; break;
1092   case SystemZ::CLFIMux:
1093   case SystemZ::CLFI:
1094     if (isUInt<16>(MI.getOperand(1).getImm()))
1095       MemImmOpc = SystemZ::CLFHSI;
1096     break;
1097   case SystemZ::CLGFI:
1098     if (isUInt<16>(MI.getOperand(1).getImm()))
1099       MemImmOpc = SystemZ::CLGHSI;
1100     break;
1101   default: break;
1102   }
1103   if (MemImmOpc)
1104     return BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(),
1105                    get(MemImmOpc))
1106                .addFrameIndex(FrameIndex)
1107                .addImm(0)
1108                .addImm(MI.getOperand(1).getImm());
1109 
1110   if (Opcode == SystemZ::LGDR || Opcode == SystemZ::LDGR) {
1111     bool Op0IsGPR = (Opcode == SystemZ::LGDR);
1112     bool Op1IsGPR = (Opcode == SystemZ::LDGR);
1113     // If we're spilling the destination of an LDGR or LGDR, store the
1114     // source register instead.
1115     if (OpNum == 0) {
1116       unsigned StoreOpcode = Op1IsGPR ? SystemZ::STG : SystemZ::STD;
1117       return BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(),
1118                      get(StoreOpcode))
1119           .add(MI.getOperand(1))
1120           .addFrameIndex(FrameIndex)
1121           .addImm(0)
1122           .addReg(0);
1123     }
1124     // If we're spilling the source of an LDGR or LGDR, load the
1125     // destination register instead.
1126     if (OpNum == 1) {
1127       unsigned LoadOpcode = Op0IsGPR ? SystemZ::LG : SystemZ::LD;
1128       return BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(),
1129                      get(LoadOpcode))
1130         .add(MI.getOperand(0))
1131         .addFrameIndex(FrameIndex)
1132         .addImm(0)
1133         .addReg(0);
1134     }
1135   }
1136 
1137   // Look for cases where the source of a simple store or the destination
1138   // of a simple load is being spilled.  Try to use MVC instead.
1139   //
1140   // Although MVC is in practice a fast choice in these cases, it is still
1141   // logically a bytewise copy.  This means that we cannot use it if the
1142   // load or store is volatile.  We also wouldn't be able to use MVC if
1143   // the two memories partially overlap, but that case cannot occur here,
1144   // because we know that one of the memories is a full frame index.
1145   //
1146   // For performance reasons, we also want to avoid using MVC if the addresses
1147   // might be equal.  We don't worry about that case here, because spill slot
1148   // coloring happens later, and because we have special code to remove
1149   // MVCs that turn out to be redundant.
1150   if (OpNum == 0 && MI.hasOneMemOperand()) {
1151     MachineMemOperand *MMO = *MI.memoperands_begin();
1152     if (MMO->getSize() == Size && !MMO->isVolatile() && !MMO->isAtomic()) {
1153       // Handle conversion of loads.
1154       if (isSimpleBD12Move(&MI, SystemZII::SimpleBDXLoad)) {
1155         return BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(),
1156                        get(SystemZ::MVC))
1157             .addFrameIndex(FrameIndex)
1158             .addImm(0)
1159             .addImm(Size)
1160             .add(MI.getOperand(1))
1161             .addImm(MI.getOperand(2).getImm())
1162             .addMemOperand(MMO);
1163       }
1164       // Handle conversion of stores.
1165       if (isSimpleBD12Move(&MI, SystemZII::SimpleBDXStore)) {
1166         return BuildMI(*InsertPt->getParent(), InsertPt, MI.getDebugLoc(),
1167                        get(SystemZ::MVC))
1168             .add(MI.getOperand(1))
1169             .addImm(MI.getOperand(2).getImm())
1170             .addImm(Size)
1171             .addFrameIndex(FrameIndex)
1172             .addImm(0)
1173             .addMemOperand(MMO);
1174       }
1175     }
1176   }
1177 
1178   // If the spilled operand is the final one or the instruction is
1179   // commutable, try to change <INSN>R into <INSN>.  Don't introduce a def of
1180   // CC if it is live and MI does not define it.
1181   unsigned NumOps = MI.getNumExplicitOperands();
1182   int MemOpcode = SystemZ::getMemOpcode(Opcode);
1183   if (MemOpcode == -1 ||
1184       (CCLiveAtMI && !MI.definesRegister(SystemZ::CC) &&
1185        get(MemOpcode).hasImplicitDefOfPhysReg(SystemZ::CC)))
1186     return nullptr;
1187 
1188   // Check if all other vregs have a usable allocation in the case of vector
1189   // to FP conversion.
1190   const MCInstrDesc &MCID = MI.getDesc();
1191   for (unsigned I = 0, E = MCID.getNumOperands(); I != E; ++I) {
1192     const MCOperandInfo &MCOI = MCID.OpInfo[I];
1193     if (MCOI.OperandType != MCOI::OPERAND_REGISTER || I == OpNum)
1194       continue;
1195     const TargetRegisterClass *RC = TRI->getRegClass(MCOI.RegClass);
1196     if (RC == &SystemZ::VR32BitRegClass || RC == &SystemZ::VR64BitRegClass) {
1197       Register Reg = MI.getOperand(I).getReg();
1198       Register PhysReg = Register::isVirtualRegister(Reg)
1199                              ? (VRM ? VRM->getPhys(Reg) : Register())
1200                              : Reg;
1201       if (!PhysReg ||
1202           !(SystemZ::FP32BitRegClass.contains(PhysReg) ||
1203             SystemZ::FP64BitRegClass.contains(PhysReg) ||
1204             SystemZ::VF128BitRegClass.contains(PhysReg)))
1205         return nullptr;
1206     }
1207   }
1208   // Fused multiply and add/sub need to have the same dst and accumulator reg.
1209   bool FusedFPOp = (Opcode == SystemZ::WFMADB || Opcode == SystemZ::WFMASB ||
1210                     Opcode == SystemZ::WFMSDB || Opcode == SystemZ::WFMSSB);
1211   if (FusedFPOp) {
1212     Register DstReg = VRM->getPhys(MI.getOperand(0).getReg());
1213     Register AccReg = VRM->getPhys(MI.getOperand(3).getReg());
1214     if (OpNum == 0 || OpNum == 3 || DstReg != AccReg)
1215       return nullptr;
1216   }
1217 
1218   // Try to swap compare operands if possible.
1219   bool NeedsCommute = false;
1220   if ((MI.getOpcode() == SystemZ::CR || MI.getOpcode() == SystemZ::CGR ||
1221        MI.getOpcode() == SystemZ::CLR || MI.getOpcode() == SystemZ::CLGR ||
1222        MI.getOpcode() == SystemZ::WFCDB || MI.getOpcode() == SystemZ::WFCSB ||
1223        MI.getOpcode() == SystemZ::WFKDB || MI.getOpcode() == SystemZ::WFKSB) &&
1224       OpNum == 0 && prepareCompareSwapOperands(MI))
1225     NeedsCommute = true;
1226 
1227   bool CCOperands = false;
1228   if (MI.getOpcode() == SystemZ::LOCRMux || MI.getOpcode() == SystemZ::LOCGR ||
1229       MI.getOpcode() == SystemZ::SELRMux || MI.getOpcode() == SystemZ::SELGR) {
1230     assert(MI.getNumOperands() == 6 && NumOps == 5 &&
1231            "LOCR/SELR instruction operands corrupt?");
1232     NumOps -= 2;
1233     CCOperands = true;
1234   }
1235 
1236   // See if this is a 3-address instruction that is convertible to 2-address
1237   // and suitable for folding below.  Only try this with virtual registers
1238   // and a provided VRM (during regalloc).
1239   if (NumOps == 3 && SystemZ::getTargetMemOpcode(MemOpcode) != -1) {
1240     if (VRM == nullptr)
1241       return nullptr;
1242     else {
1243       Register DstReg = MI.getOperand(0).getReg();
1244       Register DstPhys =
1245           (Register::isVirtualRegister(DstReg) ? VRM->getPhys(DstReg) : DstReg);
1246       Register SrcReg = (OpNum == 2 ? MI.getOperand(1).getReg()
1247                                     : ((OpNum == 1 && MI.isCommutable())
1248                                            ? MI.getOperand(2).getReg()
1249                                            : Register()));
1250       if (DstPhys && !SystemZ::GRH32BitRegClass.contains(DstPhys) && SrcReg &&
1251           Register::isVirtualRegister(SrcReg) &&
1252           DstPhys == VRM->getPhys(SrcReg))
1253         NeedsCommute = (OpNum == 1);
1254       else
1255         return nullptr;
1256     }
1257   }
1258 
1259   if ((OpNum == NumOps - 1) || NeedsCommute || FusedFPOp) {
1260     const MCInstrDesc &MemDesc = get(MemOpcode);
1261     uint64_t AccessBytes = SystemZII::getAccessSize(MemDesc.TSFlags);
1262     assert(AccessBytes != 0 && "Size of access should be known");
1263     assert(AccessBytes <= Size && "Access outside the frame index");
1264     uint64_t Offset = Size - AccessBytes;
1265     MachineInstrBuilder MIB = BuildMI(*InsertPt->getParent(), InsertPt,
1266                                       MI.getDebugLoc(), get(MemOpcode));
1267     if (MI.isCompare()) {
1268       assert(NumOps == 2 && "Expected 2 register operands for a compare.");
1269       MIB.add(MI.getOperand(NeedsCommute ? 1 : 0));
1270     }
1271     else if (FusedFPOp) {
1272       MIB.add(MI.getOperand(0));
1273       MIB.add(MI.getOperand(3));
1274       MIB.add(MI.getOperand(OpNum == 1 ? 2 : 1));
1275     }
1276     else {
1277       MIB.add(MI.getOperand(0));
1278       if (NeedsCommute)
1279         MIB.add(MI.getOperand(2));
1280       else
1281         for (unsigned I = 1; I < OpNum; ++I)
1282           MIB.add(MI.getOperand(I));
1283     }
1284     MIB.addFrameIndex(FrameIndex).addImm(Offset);
1285     if (MemDesc.TSFlags & SystemZII::HasIndex)
1286       MIB.addReg(0);
1287     if (CCOperands) {
1288       unsigned CCValid = MI.getOperand(NumOps).getImm();
1289       unsigned CCMask = MI.getOperand(NumOps + 1).getImm();
1290       MIB.addImm(CCValid);
1291       MIB.addImm(NeedsCommute ? CCMask ^ CCValid : CCMask);
1292     }
1293     if (MIB->definesRegister(SystemZ::CC) &&
1294         (!MI.definesRegister(SystemZ::CC) ||
1295          MI.registerDefIsDead(SystemZ::CC))) {
1296       MIB->addRegisterDead(SystemZ::CC, TRI);
1297       if (CCLiveRange)
1298         CCLiveRange->createDeadDef(MISlot, LIS->getVNInfoAllocator());
1299     }
1300     // Constrain the register classes if converted from a vector opcode. The
1301     // allocated regs are in an FP reg-class per previous check above.
1302     for (const MachineOperand &MO : MIB->operands())
1303       if (MO.isReg() && Register::isVirtualRegister(MO.getReg())) {
1304         unsigned Reg = MO.getReg();
1305         if (MRI.getRegClass(Reg) == &SystemZ::VR32BitRegClass)
1306           MRI.setRegClass(Reg, &SystemZ::FP32BitRegClass);
1307         else if (MRI.getRegClass(Reg) == &SystemZ::VR64BitRegClass)
1308           MRI.setRegClass(Reg, &SystemZ::FP64BitRegClass);
1309         else if (MRI.getRegClass(Reg) == &SystemZ::VR128BitRegClass)
1310           MRI.setRegClass(Reg, &SystemZ::VF128BitRegClass);
1311       }
1312 
1313     transferDeadCC(&MI, MIB);
1314     transferMIFlag(&MI, MIB, MachineInstr::NoSWrap);
1315     transferMIFlag(&MI, MIB, MachineInstr::NoFPExcept);
1316     return MIB;
1317   }
1318 
1319   return nullptr;
1320 }
1321 
1322 MachineInstr *SystemZInstrInfo::foldMemoryOperandImpl(
1323     MachineFunction &MF, MachineInstr &MI, ArrayRef<unsigned> Ops,
1324     MachineBasicBlock::iterator InsertPt, MachineInstr &LoadMI,
1325     LiveIntervals *LIS) const {
1326   return nullptr;
1327 }
1328 
1329 bool SystemZInstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
1330   switch (MI.getOpcode()) {
1331   case SystemZ::L128:
1332     splitMove(MI, SystemZ::LG);
1333     return true;
1334 
1335   case SystemZ::ST128:
1336     splitMove(MI, SystemZ::STG);
1337     return true;
1338 
1339   case SystemZ::LX:
1340     splitMove(MI, SystemZ::LD);
1341     return true;
1342 
1343   case SystemZ::STX:
1344     splitMove(MI, SystemZ::STD);
1345     return true;
1346 
1347   case SystemZ::LBMux:
1348     expandRXYPseudo(MI, SystemZ::LB, SystemZ::LBH);
1349     return true;
1350 
1351   case SystemZ::LHMux:
1352     expandRXYPseudo(MI, SystemZ::LH, SystemZ::LHH);
1353     return true;
1354 
1355   case SystemZ::LLCRMux:
1356     expandZExtPseudo(MI, SystemZ::LLCR, 8);
1357     return true;
1358 
1359   case SystemZ::LLHRMux:
1360     expandZExtPseudo(MI, SystemZ::LLHR, 16);
1361     return true;
1362 
1363   case SystemZ::LLCMux:
1364     expandRXYPseudo(MI, SystemZ::LLC, SystemZ::LLCH);
1365     return true;
1366 
1367   case SystemZ::LLHMux:
1368     expandRXYPseudo(MI, SystemZ::LLH, SystemZ::LLHH);
1369     return true;
1370 
1371   case SystemZ::LMux:
1372     expandRXYPseudo(MI, SystemZ::L, SystemZ::LFH);
1373     return true;
1374 
1375   case SystemZ::LOCMux:
1376     expandLOCPseudo(MI, SystemZ::LOC, SystemZ::LOCFH);
1377     return true;
1378 
1379   case SystemZ::LOCHIMux:
1380     expandLOCPseudo(MI, SystemZ::LOCHI, SystemZ::LOCHHI);
1381     return true;
1382 
1383   case SystemZ::STCMux:
1384     expandRXYPseudo(MI, SystemZ::STC, SystemZ::STCH);
1385     return true;
1386 
1387   case SystemZ::STHMux:
1388     expandRXYPseudo(MI, SystemZ::STH, SystemZ::STHH);
1389     return true;
1390 
1391   case SystemZ::STMux:
1392     expandRXYPseudo(MI, SystemZ::ST, SystemZ::STFH);
1393     return true;
1394 
1395   case SystemZ::STOCMux:
1396     expandLOCPseudo(MI, SystemZ::STOC, SystemZ::STOCFH);
1397     return true;
1398 
1399   case SystemZ::LHIMux:
1400     expandRIPseudo(MI, SystemZ::LHI, SystemZ::IIHF, true);
1401     return true;
1402 
1403   case SystemZ::IIFMux:
1404     expandRIPseudo(MI, SystemZ::IILF, SystemZ::IIHF, false);
1405     return true;
1406 
1407   case SystemZ::IILMux:
1408     expandRIPseudo(MI, SystemZ::IILL, SystemZ::IIHL, false);
1409     return true;
1410 
1411   case SystemZ::IIHMux:
1412     expandRIPseudo(MI, SystemZ::IILH, SystemZ::IIHH, false);
1413     return true;
1414 
1415   case SystemZ::NIFMux:
1416     expandRIPseudo(MI, SystemZ::NILF, SystemZ::NIHF, false);
1417     return true;
1418 
1419   case SystemZ::NILMux:
1420     expandRIPseudo(MI, SystemZ::NILL, SystemZ::NIHL, false);
1421     return true;
1422 
1423   case SystemZ::NIHMux:
1424     expandRIPseudo(MI, SystemZ::NILH, SystemZ::NIHH, false);
1425     return true;
1426 
1427   case SystemZ::OIFMux:
1428     expandRIPseudo(MI, SystemZ::OILF, SystemZ::OIHF, false);
1429     return true;
1430 
1431   case SystemZ::OILMux:
1432     expandRIPseudo(MI, SystemZ::OILL, SystemZ::OIHL, false);
1433     return true;
1434 
1435   case SystemZ::OIHMux:
1436     expandRIPseudo(MI, SystemZ::OILH, SystemZ::OIHH, false);
1437     return true;
1438 
1439   case SystemZ::XIFMux:
1440     expandRIPseudo(MI, SystemZ::XILF, SystemZ::XIHF, false);
1441     return true;
1442 
1443   case SystemZ::TMLMux:
1444     expandRIPseudo(MI, SystemZ::TMLL, SystemZ::TMHL, false);
1445     return true;
1446 
1447   case SystemZ::TMHMux:
1448     expandRIPseudo(MI, SystemZ::TMLH, SystemZ::TMHH, false);
1449     return true;
1450 
1451   case SystemZ::AHIMux:
1452     expandRIPseudo(MI, SystemZ::AHI, SystemZ::AIH, false);
1453     return true;
1454 
1455   case SystemZ::AHIMuxK:
1456     expandRIEPseudo(MI, SystemZ::AHI, SystemZ::AHIK, SystemZ::AIH);
1457     return true;
1458 
1459   case SystemZ::AFIMux:
1460     expandRIPseudo(MI, SystemZ::AFI, SystemZ::AIH, false);
1461     return true;
1462 
1463   case SystemZ::CHIMux:
1464     expandRIPseudo(MI, SystemZ::CHI, SystemZ::CIH, false);
1465     return true;
1466 
1467   case SystemZ::CFIMux:
1468     expandRIPseudo(MI, SystemZ::CFI, SystemZ::CIH, false);
1469     return true;
1470 
1471   case SystemZ::CLFIMux:
1472     expandRIPseudo(MI, SystemZ::CLFI, SystemZ::CLIH, false);
1473     return true;
1474 
1475   case SystemZ::CMux:
1476     expandRXYPseudo(MI, SystemZ::C, SystemZ::CHF);
1477     return true;
1478 
1479   case SystemZ::CLMux:
1480     expandRXYPseudo(MI, SystemZ::CL, SystemZ::CLHF);
1481     return true;
1482 
1483   case SystemZ::RISBMux: {
1484     bool DestIsHigh = SystemZ::isHighReg(MI.getOperand(0).getReg());
1485     bool SrcIsHigh = SystemZ::isHighReg(MI.getOperand(2).getReg());
1486     if (SrcIsHigh == DestIsHigh)
1487       MI.setDesc(get(DestIsHigh ? SystemZ::RISBHH : SystemZ::RISBLL));
1488     else {
1489       MI.setDesc(get(DestIsHigh ? SystemZ::RISBHL : SystemZ::RISBLH));
1490       MI.getOperand(5).setImm(MI.getOperand(5).getImm() ^ 32);
1491     }
1492     return true;
1493   }
1494 
1495   case SystemZ::ADJDYNALLOC:
1496     splitAdjDynAlloc(MI);
1497     return true;
1498 
1499   case TargetOpcode::LOAD_STACK_GUARD:
1500     expandLoadStackGuard(&MI);
1501     return true;
1502 
1503   default:
1504     return false;
1505   }
1506 }
1507 
1508 unsigned SystemZInstrInfo::getInstSizeInBytes(const MachineInstr &MI) const {
1509   if (MI.isInlineAsm()) {
1510     const MachineFunction *MF = MI.getParent()->getParent();
1511     const char *AsmStr = MI.getOperand(0).getSymbolName();
1512     return getInlineAsmLength(AsmStr, *MF->getTarget().getMCAsmInfo());
1513   }
1514   return MI.getDesc().getSize();
1515 }
1516 
1517 SystemZII::Branch
1518 SystemZInstrInfo::getBranchInfo(const MachineInstr &MI) const {
1519   switch (MI.getOpcode()) {
1520   case SystemZ::BR:
1521   case SystemZ::BI:
1522   case SystemZ::J:
1523   case SystemZ::JG:
1524     return SystemZII::Branch(SystemZII::BranchNormal, SystemZ::CCMASK_ANY,
1525                              SystemZ::CCMASK_ANY, &MI.getOperand(0));
1526 
1527   case SystemZ::BRC:
1528   case SystemZ::BRCL:
1529     return SystemZII::Branch(SystemZII::BranchNormal, MI.getOperand(0).getImm(),
1530                              MI.getOperand(1).getImm(), &MI.getOperand(2));
1531 
1532   case SystemZ::BRCT:
1533   case SystemZ::BRCTH:
1534     return SystemZII::Branch(SystemZII::BranchCT, SystemZ::CCMASK_ICMP,
1535                              SystemZ::CCMASK_CMP_NE, &MI.getOperand(2));
1536 
1537   case SystemZ::BRCTG:
1538     return SystemZII::Branch(SystemZII::BranchCTG, SystemZ::CCMASK_ICMP,
1539                              SystemZ::CCMASK_CMP_NE, &MI.getOperand(2));
1540 
1541   case SystemZ::CIJ:
1542   case SystemZ::CRJ:
1543     return SystemZII::Branch(SystemZII::BranchC, SystemZ::CCMASK_ICMP,
1544                              MI.getOperand(2).getImm(), &MI.getOperand(3));
1545 
1546   case SystemZ::CLIJ:
1547   case SystemZ::CLRJ:
1548     return SystemZII::Branch(SystemZII::BranchCL, SystemZ::CCMASK_ICMP,
1549                              MI.getOperand(2).getImm(), &MI.getOperand(3));
1550 
1551   case SystemZ::CGIJ:
1552   case SystemZ::CGRJ:
1553     return SystemZII::Branch(SystemZII::BranchCG, SystemZ::CCMASK_ICMP,
1554                              MI.getOperand(2).getImm(), &MI.getOperand(3));
1555 
1556   case SystemZ::CLGIJ:
1557   case SystemZ::CLGRJ:
1558     return SystemZII::Branch(SystemZII::BranchCLG, SystemZ::CCMASK_ICMP,
1559                              MI.getOperand(2).getImm(), &MI.getOperand(3));
1560 
1561   case SystemZ::INLINEASM_BR:
1562     // Don't try to analyze asm goto, so pass nullptr as branch target argument.
1563     return SystemZII::Branch(SystemZII::AsmGoto, 0, 0, nullptr);
1564 
1565   default:
1566     llvm_unreachable("Unrecognized branch opcode");
1567   }
1568 }
1569 
1570 void SystemZInstrInfo::getLoadStoreOpcodes(const TargetRegisterClass *RC,
1571                                            unsigned &LoadOpcode,
1572                                            unsigned &StoreOpcode) const {
1573   if (RC == &SystemZ::GR32BitRegClass || RC == &SystemZ::ADDR32BitRegClass) {
1574     LoadOpcode = SystemZ::L;
1575     StoreOpcode = SystemZ::ST;
1576   } else if (RC == &SystemZ::GRH32BitRegClass) {
1577     LoadOpcode = SystemZ::LFH;
1578     StoreOpcode = SystemZ::STFH;
1579   } else if (RC == &SystemZ::GRX32BitRegClass) {
1580     LoadOpcode = SystemZ::LMux;
1581     StoreOpcode = SystemZ::STMux;
1582   } else if (RC == &SystemZ::GR64BitRegClass ||
1583              RC == &SystemZ::ADDR64BitRegClass) {
1584     LoadOpcode = SystemZ::LG;
1585     StoreOpcode = SystemZ::STG;
1586   } else if (RC == &SystemZ::GR128BitRegClass ||
1587              RC == &SystemZ::ADDR128BitRegClass) {
1588     LoadOpcode = SystemZ::L128;
1589     StoreOpcode = SystemZ::ST128;
1590   } else if (RC == &SystemZ::FP32BitRegClass) {
1591     LoadOpcode = SystemZ::LE;
1592     StoreOpcode = SystemZ::STE;
1593   } else if (RC == &SystemZ::FP64BitRegClass) {
1594     LoadOpcode = SystemZ::LD;
1595     StoreOpcode = SystemZ::STD;
1596   } else if (RC == &SystemZ::FP128BitRegClass) {
1597     LoadOpcode = SystemZ::LX;
1598     StoreOpcode = SystemZ::STX;
1599   } else if (RC == &SystemZ::VR32BitRegClass) {
1600     LoadOpcode = SystemZ::VL32;
1601     StoreOpcode = SystemZ::VST32;
1602   } else if (RC == &SystemZ::VR64BitRegClass) {
1603     LoadOpcode = SystemZ::VL64;
1604     StoreOpcode = SystemZ::VST64;
1605   } else if (RC == &SystemZ::VF128BitRegClass ||
1606              RC == &SystemZ::VR128BitRegClass) {
1607     LoadOpcode = SystemZ::VL;
1608     StoreOpcode = SystemZ::VST;
1609   } else
1610     llvm_unreachable("Unsupported regclass to load or store");
1611 }
1612 
1613 unsigned SystemZInstrInfo::getOpcodeForOffset(unsigned Opcode,
1614                                               int64_t Offset) const {
1615   const MCInstrDesc &MCID = get(Opcode);
1616   int64_t Offset2 = (MCID.TSFlags & SystemZII::Is128Bit ? Offset + 8 : Offset);
1617   if (isUInt<12>(Offset) && isUInt<12>(Offset2)) {
1618     // Get the instruction to use for unsigned 12-bit displacements.
1619     int Disp12Opcode = SystemZ::getDisp12Opcode(Opcode);
1620     if (Disp12Opcode >= 0)
1621       return Disp12Opcode;
1622 
1623     // All address-related instructions can use unsigned 12-bit
1624     // displacements.
1625     return Opcode;
1626   }
1627   if (isInt<20>(Offset) && isInt<20>(Offset2)) {
1628     // Get the instruction to use for signed 20-bit displacements.
1629     int Disp20Opcode = SystemZ::getDisp20Opcode(Opcode);
1630     if (Disp20Opcode >= 0)
1631       return Disp20Opcode;
1632 
1633     // Check whether Opcode allows signed 20-bit displacements.
1634     if (MCID.TSFlags & SystemZII::Has20BitOffset)
1635       return Opcode;
1636   }
1637   return 0;
1638 }
1639 
1640 unsigned SystemZInstrInfo::getLoadAndTest(unsigned Opcode) const {
1641   switch (Opcode) {
1642   case SystemZ::L:      return SystemZ::LT;
1643   case SystemZ::LY:     return SystemZ::LT;
1644   case SystemZ::LG:     return SystemZ::LTG;
1645   case SystemZ::LGF:    return SystemZ::LTGF;
1646   case SystemZ::LR:     return SystemZ::LTR;
1647   case SystemZ::LGFR:   return SystemZ::LTGFR;
1648   case SystemZ::LGR:    return SystemZ::LTGR;
1649   case SystemZ::LER:    return SystemZ::LTEBR;
1650   case SystemZ::LDR:    return SystemZ::LTDBR;
1651   case SystemZ::LXR:    return SystemZ::LTXBR;
1652   case SystemZ::LCDFR:  return SystemZ::LCDBR;
1653   case SystemZ::LPDFR:  return SystemZ::LPDBR;
1654   case SystemZ::LNDFR:  return SystemZ::LNDBR;
1655   case SystemZ::LCDFR_32:  return SystemZ::LCEBR;
1656   case SystemZ::LPDFR_32:  return SystemZ::LPEBR;
1657   case SystemZ::LNDFR_32:  return SystemZ::LNEBR;
1658   // On zEC12 we prefer to use RISBGN.  But if there is a chance to
1659   // actually use the condition code, we may turn it back into RISGB.
1660   // Note that RISBG is not really a "load-and-test" instruction,
1661   // but sets the same condition code values, so is OK to use here.
1662   case SystemZ::RISBGN: return SystemZ::RISBG;
1663   default:              return 0;
1664   }
1665 }
1666 
1667 // Return true if Mask matches the regexp 0*1+0*, given that zero masks
1668 // have already been filtered out.  Store the first set bit in LSB and
1669 // the number of set bits in Length if so.
1670 static bool isStringOfOnes(uint64_t Mask, unsigned &LSB, unsigned &Length) {
1671   unsigned First = findFirstSet(Mask);
1672   uint64_t Top = (Mask >> First) + 1;
1673   if ((Top & -Top) == Top) {
1674     LSB = First;
1675     Length = findFirstSet(Top);
1676     return true;
1677   }
1678   return false;
1679 }
1680 
1681 bool SystemZInstrInfo::isRxSBGMask(uint64_t Mask, unsigned BitSize,
1682                                    unsigned &Start, unsigned &End) const {
1683   // Reject trivial all-zero masks.
1684   Mask &= allOnes(BitSize);
1685   if (Mask == 0)
1686     return false;
1687 
1688   // Handle the 1+0+ or 0+1+0* cases.  Start then specifies the index of
1689   // the msb and End specifies the index of the lsb.
1690   unsigned LSB, Length;
1691   if (isStringOfOnes(Mask, LSB, Length)) {
1692     Start = 63 - (LSB + Length - 1);
1693     End = 63 - LSB;
1694     return true;
1695   }
1696 
1697   // Handle the wrap-around 1+0+1+ cases.  Start then specifies the msb
1698   // of the low 1s and End specifies the lsb of the high 1s.
1699   if (isStringOfOnes(Mask ^ allOnes(BitSize), LSB, Length)) {
1700     assert(LSB > 0 && "Bottom bit must be set");
1701     assert(LSB + Length < BitSize && "Top bit must be set");
1702     Start = 63 - (LSB - 1);
1703     End = 63 - (LSB + Length);
1704     return true;
1705   }
1706 
1707   return false;
1708 }
1709 
1710 unsigned SystemZInstrInfo::getFusedCompare(unsigned Opcode,
1711                                            SystemZII::FusedCompareType Type,
1712                                            const MachineInstr *MI) const {
1713   switch (Opcode) {
1714   case SystemZ::CHI:
1715   case SystemZ::CGHI:
1716     if (!(MI && isInt<8>(MI->getOperand(1).getImm())))
1717       return 0;
1718     break;
1719   case SystemZ::CLFI:
1720   case SystemZ::CLGFI:
1721     if (!(MI && isUInt<8>(MI->getOperand(1).getImm())))
1722       return 0;
1723     break;
1724   case SystemZ::CL:
1725   case SystemZ::CLG:
1726     if (!STI.hasMiscellaneousExtensions())
1727       return 0;
1728     if (!(MI && MI->getOperand(3).getReg() == 0))
1729       return 0;
1730     break;
1731   }
1732   switch (Type) {
1733   case SystemZII::CompareAndBranch:
1734     switch (Opcode) {
1735     case SystemZ::CR:
1736       return SystemZ::CRJ;
1737     case SystemZ::CGR:
1738       return SystemZ::CGRJ;
1739     case SystemZ::CHI:
1740       return SystemZ::CIJ;
1741     case SystemZ::CGHI:
1742       return SystemZ::CGIJ;
1743     case SystemZ::CLR:
1744       return SystemZ::CLRJ;
1745     case SystemZ::CLGR:
1746       return SystemZ::CLGRJ;
1747     case SystemZ::CLFI:
1748       return SystemZ::CLIJ;
1749     case SystemZ::CLGFI:
1750       return SystemZ::CLGIJ;
1751     default:
1752       return 0;
1753     }
1754   case SystemZII::CompareAndReturn:
1755     switch (Opcode) {
1756     case SystemZ::CR:
1757       return SystemZ::CRBReturn;
1758     case SystemZ::CGR:
1759       return SystemZ::CGRBReturn;
1760     case SystemZ::CHI:
1761       return SystemZ::CIBReturn;
1762     case SystemZ::CGHI:
1763       return SystemZ::CGIBReturn;
1764     case SystemZ::CLR:
1765       return SystemZ::CLRBReturn;
1766     case SystemZ::CLGR:
1767       return SystemZ::CLGRBReturn;
1768     case SystemZ::CLFI:
1769       return SystemZ::CLIBReturn;
1770     case SystemZ::CLGFI:
1771       return SystemZ::CLGIBReturn;
1772     default:
1773       return 0;
1774     }
1775   case SystemZII::CompareAndSibcall:
1776     switch (Opcode) {
1777     case SystemZ::CR:
1778       return SystemZ::CRBCall;
1779     case SystemZ::CGR:
1780       return SystemZ::CGRBCall;
1781     case SystemZ::CHI:
1782       return SystemZ::CIBCall;
1783     case SystemZ::CGHI:
1784       return SystemZ::CGIBCall;
1785     case SystemZ::CLR:
1786       return SystemZ::CLRBCall;
1787     case SystemZ::CLGR:
1788       return SystemZ::CLGRBCall;
1789     case SystemZ::CLFI:
1790       return SystemZ::CLIBCall;
1791     case SystemZ::CLGFI:
1792       return SystemZ::CLGIBCall;
1793     default:
1794       return 0;
1795     }
1796   case SystemZII::CompareAndTrap:
1797     switch (Opcode) {
1798     case SystemZ::CR:
1799       return SystemZ::CRT;
1800     case SystemZ::CGR:
1801       return SystemZ::CGRT;
1802     case SystemZ::CHI:
1803       return SystemZ::CIT;
1804     case SystemZ::CGHI:
1805       return SystemZ::CGIT;
1806     case SystemZ::CLR:
1807       return SystemZ::CLRT;
1808     case SystemZ::CLGR:
1809       return SystemZ::CLGRT;
1810     case SystemZ::CLFI:
1811       return SystemZ::CLFIT;
1812     case SystemZ::CLGFI:
1813       return SystemZ::CLGIT;
1814     case SystemZ::CL:
1815       return SystemZ::CLT;
1816     case SystemZ::CLG:
1817       return SystemZ::CLGT;
1818     default:
1819       return 0;
1820     }
1821   }
1822   return 0;
1823 }
1824 
1825 bool SystemZInstrInfo::
1826 prepareCompareSwapOperands(MachineBasicBlock::iterator const MBBI) const {
1827   assert(MBBI->isCompare() && MBBI->getOperand(0).isReg() &&
1828          MBBI->getOperand(1).isReg() && !MBBI->mayLoad() &&
1829          "Not a compare reg/reg.");
1830 
1831   MachineBasicBlock *MBB = MBBI->getParent();
1832   bool CCLive = true;
1833   SmallVector<MachineInstr *, 4> CCUsers;
1834   for (MachineBasicBlock::iterator Itr = std::next(MBBI);
1835        Itr != MBB->end(); ++Itr) {
1836     if (Itr->readsRegister(SystemZ::CC)) {
1837       unsigned Flags = Itr->getDesc().TSFlags;
1838       if ((Flags & SystemZII::CCMaskFirst) || (Flags & SystemZII::CCMaskLast))
1839         CCUsers.push_back(&*Itr);
1840       else
1841         return false;
1842     }
1843     if (Itr->definesRegister(SystemZ::CC)) {
1844       CCLive = false;
1845       break;
1846     }
1847   }
1848   if (CCLive) {
1849     LivePhysRegs LiveRegs(*MBB->getParent()->getSubtarget().getRegisterInfo());
1850     LiveRegs.addLiveOuts(*MBB);
1851     if (LiveRegs.contains(SystemZ::CC))
1852       return false;
1853   }
1854 
1855   // Update all CC users.
1856   for (unsigned Idx = 0; Idx < CCUsers.size(); ++Idx) {
1857     unsigned Flags = CCUsers[Idx]->getDesc().TSFlags;
1858     unsigned FirstOpNum = ((Flags & SystemZII::CCMaskFirst) ?
1859                            0 : CCUsers[Idx]->getNumExplicitOperands() - 2);
1860     MachineOperand &CCMaskMO = CCUsers[Idx]->getOperand(FirstOpNum + 1);
1861     unsigned NewCCMask = SystemZ::reverseCCMask(CCMaskMO.getImm());
1862     CCMaskMO.setImm(NewCCMask);
1863   }
1864 
1865   return true;
1866 }
1867 
1868 unsigned SystemZ::reverseCCMask(unsigned CCMask) {
1869   return ((CCMask & SystemZ::CCMASK_CMP_EQ) |
1870           (CCMask & SystemZ::CCMASK_CMP_GT ? SystemZ::CCMASK_CMP_LT : 0) |
1871           (CCMask & SystemZ::CCMASK_CMP_LT ? SystemZ::CCMASK_CMP_GT : 0) |
1872           (CCMask & SystemZ::CCMASK_CMP_UO));
1873 }
1874 
1875 MachineBasicBlock *SystemZ::emitBlockAfter(MachineBasicBlock *MBB) {
1876   MachineFunction &MF = *MBB->getParent();
1877   MachineBasicBlock *NewMBB = MF.CreateMachineBasicBlock(MBB->getBasicBlock());
1878   MF.insert(std::next(MachineFunction::iterator(MBB)), NewMBB);
1879   return NewMBB;
1880 }
1881 
1882 MachineBasicBlock *SystemZ::splitBlockAfter(MachineBasicBlock::iterator MI,
1883                                             MachineBasicBlock *MBB) {
1884   MachineBasicBlock *NewMBB = emitBlockAfter(MBB);
1885   NewMBB->splice(NewMBB->begin(), MBB,
1886                  std::next(MachineBasicBlock::iterator(MI)), MBB->end());
1887   NewMBB->transferSuccessorsAndUpdatePHIs(MBB);
1888   return NewMBB;
1889 }
1890 
1891 MachineBasicBlock *SystemZ::splitBlockBefore(MachineBasicBlock::iterator MI,
1892                                              MachineBasicBlock *MBB) {
1893   MachineBasicBlock *NewMBB = emitBlockAfter(MBB);
1894   NewMBB->splice(NewMBB->begin(), MBB, MI, MBB->end());
1895   NewMBB->transferSuccessorsAndUpdatePHIs(MBB);
1896   return NewMBB;
1897 }
1898 
1899 unsigned SystemZInstrInfo::getLoadAndTrap(unsigned Opcode) const {
1900   if (!STI.hasLoadAndTrap())
1901     return 0;
1902   switch (Opcode) {
1903   case SystemZ::L:
1904   case SystemZ::LY:
1905     return SystemZ::LAT;
1906   case SystemZ::LG:
1907     return SystemZ::LGAT;
1908   case SystemZ::LFH:
1909     return SystemZ::LFHAT;
1910   case SystemZ::LLGF:
1911     return SystemZ::LLGFAT;
1912   case SystemZ::LLGT:
1913     return SystemZ::LLGTAT;
1914   }
1915   return 0;
1916 }
1917 
1918 void SystemZInstrInfo::loadImmediate(MachineBasicBlock &MBB,
1919                                      MachineBasicBlock::iterator MBBI,
1920                                      unsigned Reg, uint64_t Value) const {
1921   DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
1922   unsigned Opcode;
1923   if (isInt<16>(Value))
1924     Opcode = SystemZ::LGHI;
1925   else if (SystemZ::isImmLL(Value))
1926     Opcode = SystemZ::LLILL;
1927   else if (SystemZ::isImmLH(Value)) {
1928     Opcode = SystemZ::LLILH;
1929     Value >>= 16;
1930   } else {
1931     assert(isInt<32>(Value) && "Huge values not handled yet");
1932     Opcode = SystemZ::LGFI;
1933   }
1934   BuildMI(MBB, MBBI, DL, get(Opcode), Reg).addImm(Value);
1935 }
1936 
1937 bool SystemZInstrInfo::verifyInstruction(const MachineInstr &MI,
1938                                          StringRef &ErrInfo) const {
1939   const MCInstrDesc &MCID = MI.getDesc();
1940   for (unsigned I = 0, E = MI.getNumOperands(); I != E; ++I) {
1941     if (I >= MCID.getNumOperands())
1942       break;
1943     const MachineOperand &Op = MI.getOperand(I);
1944     const MCOperandInfo &MCOI = MCID.OpInfo[I];
1945     // Addressing modes have register and immediate operands. Op should be a
1946     // register (or frame index) operand if MCOI.RegClass contains a valid
1947     // register class, or an immediate otherwise.
1948     if (MCOI.OperandType == MCOI::OPERAND_MEMORY &&
1949         ((MCOI.RegClass != -1 && !Op.isReg() && !Op.isFI()) ||
1950          (MCOI.RegClass == -1 && !Op.isImm()))) {
1951       ErrInfo = "Addressing mode operands corrupt!";
1952       return false;
1953     }
1954   }
1955 
1956   return true;
1957 }
1958 
1959 bool SystemZInstrInfo::
1960 areMemAccessesTriviallyDisjoint(const MachineInstr &MIa,
1961                                 const MachineInstr &MIb) const {
1962 
1963   if (!MIa.hasOneMemOperand() || !MIb.hasOneMemOperand())
1964     return false;
1965 
1966   // If mem-operands show that the same address Value is used by both
1967   // instructions, check for non-overlapping offsets and widths. Not
1968   // sure if a register based analysis would be an improvement...
1969 
1970   MachineMemOperand *MMOa = *MIa.memoperands_begin();
1971   MachineMemOperand *MMOb = *MIb.memoperands_begin();
1972   const Value *VALa = MMOa->getValue();
1973   const Value *VALb = MMOb->getValue();
1974   bool SameVal = (VALa && VALb && (VALa == VALb));
1975   if (!SameVal) {
1976     const PseudoSourceValue *PSVa = MMOa->getPseudoValue();
1977     const PseudoSourceValue *PSVb = MMOb->getPseudoValue();
1978     if (PSVa && PSVb && (PSVa == PSVb))
1979       SameVal = true;
1980   }
1981   if (SameVal) {
1982     int OffsetA = MMOa->getOffset(), OffsetB = MMOb->getOffset();
1983     int WidthA = MMOa->getSize(), WidthB = MMOb->getSize();
1984     int LowOffset = OffsetA < OffsetB ? OffsetA : OffsetB;
1985     int HighOffset = OffsetA < OffsetB ? OffsetB : OffsetA;
1986     int LowWidth = (LowOffset == OffsetA) ? WidthA : WidthB;
1987     if (LowOffset + LowWidth <= HighOffset)
1988       return true;
1989   }
1990 
1991   return false;
1992 }
1993