1 //===----- HexagonPacketizer.cpp - vliw packetizer ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This implements a simple VLIW packetizer using DFA. The packetizer works on
11 // machine basic blocks. For each instruction I in BB, the packetizer consults
12 // the DFA to see if machine resources are available to execute I. If so, the
13 // packetizer checks if I depends on any instruction J in the current packet.
14 // If no dependency is found, I is added to current packet and machine resource
15 // is marked as taken. If any dependency is found, a target API call is made to
16 // prune the dependence.
18 //===----------------------------------------------------------------------===//
19 #include "llvm/CodeGen/DFAPacketizer.h"
21 #include "HexagonMachineFunctionInfo.h"
22 #include "HexagonRegisterInfo.h"
23 #include "HexagonSubtarget.h"
24 #include "HexagonTargetMachine.h"
25 #include "llvm/ADT/DenseMap.h"
26 #include "llvm/ADT/Statistic.h"
27 #include "llvm/CodeGen/LatencyPriorityQueue.h"
28 #include "llvm/CodeGen/MachineDominators.h"
29 #include "llvm/CodeGen/MachineFrameInfo.h"
30 #include "llvm/CodeGen/MachineFunctionAnalysis.h"
31 #include "llvm/CodeGen/MachineFunctionPass.h"
32 #include "llvm/CodeGen/MachineInstrBuilder.h"
33 #include "llvm/CodeGen/MachineLoopInfo.h"
34 #include "llvm/CodeGen/MachineRegisterInfo.h"
35 #include "llvm/CodeGen/Passes.h"
36 #include "llvm/CodeGen/ScheduleDAG.h"
37 #include "llvm/CodeGen/ScheduleDAGInstrs.h"
38 #include "llvm/CodeGen/ScheduleHazardRecognizer.h"
39 #include "llvm/CodeGen/SchedulerRegistry.h"
40 #include "llvm/MC/MCInstrItineraries.h"
41 #include "llvm/Support/CommandLine.h"
42 #include "llvm/Support/Compiler.h"
43 #include "llvm/Support/Debug.h"
44 #include "llvm/Support/MathExtras.h"
45 #include "llvm/Target/TargetInstrInfo.h"
46 #include "llvm/Target/TargetMachine.h"
47 #include "llvm/Target/TargetRegisterInfo.h"
53 #define DEBUG_TYPE "packets"
55 static cl::opt<bool> PacketizeVolatiles("hexagon-packetize-volatiles",
56 cl::ZeroOrMore, cl::Hidden, cl::init(true),
57 cl::desc("Allow non-solo packetization of volatile memory references"));
60 FunctionPass *createHexagonPacketizer();
61 void initializeHexagonPacketizerPass(PassRegistry&);
66 class HexagonPacketizer : public MachineFunctionPass {
70 HexagonPacketizer() : MachineFunctionPass(ID) {
71 initializeHexagonPacketizerPass(*PassRegistry::getPassRegistry());
74 void getAnalysisUsage(AnalysisUsage &AU) const override {
76 AU.addRequired<MachineDominatorTree>();
77 AU.addRequired<MachineBranchProbabilityInfo>();
78 AU.addPreserved<MachineDominatorTree>();
79 AU.addRequired<MachineLoopInfo>();
80 AU.addPreserved<MachineLoopInfo>();
81 MachineFunctionPass::getAnalysisUsage(AU);
84 const char *getPassName() const override {
85 return "Hexagon Packetizer";
88 bool runOnMachineFunction(MachineFunction &Fn) override;
90 char HexagonPacketizer::ID = 0;
92 class HexagonPacketizerList : public VLIWPacketizerList {
96 // Has the instruction been promoted to a dot-new instruction.
97 bool PromotedToDotNew;
99 // Has the instruction been glued to allocframe.
100 bool GlueAllocframeStore;
102 // Has the feeder instruction been glued to new value jump.
103 bool GlueToNewValueJump;
105 // Check if there is a dependence between some instruction already in this
106 // packet and this instruction.
109 // Only check for dependence if there are resources available to
110 // schedule this instruction.
111 bool FoundSequentialDependence;
113 /// \brief A handle to the branch probability pass.
114 const MachineBranchProbabilityInfo *MBPI;
116 // Track MIs with ignored dependece.
117 std::vector<MachineInstr*> IgnoreDepMIs;
121 HexagonPacketizerList(MachineFunction &MF, MachineLoopInfo &MLI,
122 const MachineBranchProbabilityInfo *MBPI);
124 // initPacketizerState - initialize some internal flags.
125 void initPacketizerState() override;
127 // ignorePseudoInstruction - Ignore bundling of pseudo instructions.
128 bool ignorePseudoInstruction(MachineInstr *MI,
129 MachineBasicBlock *MBB) override;
131 // isSoloInstruction - return true if instruction MI can not be packetized
132 // with any other instruction, which means that MI itself is a packet.
133 bool isSoloInstruction(MachineInstr *MI) override;
135 // isLegalToPacketizeTogether - Is it legal to packetize SUI and SUJ
137 bool isLegalToPacketizeTogether(SUnit *SUI, SUnit *SUJ) override;
139 // isLegalToPruneDependencies - Is it legal to prune dependece between SUI
141 bool isLegalToPruneDependencies(SUnit *SUI, SUnit *SUJ) override;
143 MachineBasicBlock::iterator addToPacket(MachineInstr *MI) override;
145 bool IsCallDependent(MachineInstr* MI, SDep::Kind DepType, unsigned DepReg);
146 bool PromoteToDotNew(MachineInstr* MI, SDep::Kind DepType,
147 MachineBasicBlock::iterator &MII,
148 const TargetRegisterClass* RC);
149 bool CanPromoteToDotNew(MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
150 const std::map<MachineInstr *, SUnit *> &MIToSUnit,
151 MachineBasicBlock::iterator &MII,
152 const TargetRegisterClass *RC);
154 CanPromoteToNewValue(MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
155 const std::map<MachineInstr *, SUnit *> &MIToSUnit,
156 MachineBasicBlock::iterator &MII);
157 bool CanPromoteToNewValueStore(
158 MachineInstr *MI, MachineInstr *PacketMI, unsigned DepReg,
159 const std::map<MachineInstr *, SUnit *> &MIToSUnit);
160 bool DemoteToDotOld(MachineInstr *MI);
161 bool ArePredicatesComplements(
162 MachineInstr *MI1, MachineInstr *MI2,
163 const std::map<MachineInstr *, SUnit *> &MIToSUnit);
164 bool RestrictingDepExistInPacket(MachineInstr *, unsigned,
165 const std::map<MachineInstr *, SUnit *> &);
166 bool isNewifiable(MachineInstr* MI);
167 bool isCondInst(MachineInstr* MI);
168 bool tryAllocateResourcesForConstExt(MachineInstr* MI);
169 bool canReserveResourcesForConstExt(MachineInstr *MI);
170 void reserveResourcesForConstExt(MachineInstr* MI);
171 bool isNewValueInst(MachineInstr* MI);
175 INITIALIZE_PASS_BEGIN(HexagonPacketizer, "packets", "Hexagon Packetizer",
177 INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
178 INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
179 INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
180 INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
181 INITIALIZE_PASS_END(HexagonPacketizer, "packets", "Hexagon Packetizer",
185 // HexagonPacketizerList Ctor.
186 HexagonPacketizerList::HexagonPacketizerList(
187 MachineFunction &MF, MachineLoopInfo &MLI,
188 const MachineBranchProbabilityInfo *MBPI)
189 : VLIWPacketizerList(MF, MLI, true) {
193 bool HexagonPacketizer::runOnMachineFunction(MachineFunction &Fn) {
194 const TargetInstrInfo *TII = Fn.getSubtarget().getInstrInfo();
195 MachineLoopInfo &MLI = getAnalysis<MachineLoopInfo>();
196 const MachineBranchProbabilityInfo *MBPI =
197 &getAnalysis<MachineBranchProbabilityInfo>();
198 // Instantiate the packetizer.
199 HexagonPacketizerList Packetizer(Fn, MLI, MBPI);
201 // DFA state table should not be empty.
202 assert(Packetizer.getResourceTracker() && "Empty DFA table!");
205 // Loop over all basic blocks and remove KILL pseudo-instructions
206 // These instructions confuse the dependence analysis. Consider:
208 // R0 = KILL R0, D0 (Insn 1)
210 // Here, Insn 1 will result in the dependence graph not emitting an output
211 // dependence between Insn 0 and Insn 2. This can lead to incorrect
214 for (MachineFunction::iterator MBB = Fn.begin(), MBBe = Fn.end();
215 MBB != MBBe; ++MBB) {
216 MachineBasicBlock::iterator End = MBB->end();
217 MachineBasicBlock::iterator MI = MBB->begin();
220 MachineBasicBlock::iterator DeleteMI = MI;
222 MBB->erase(DeleteMI);
230 // Loop over all of the basic blocks.
231 for (MachineFunction::iterator MBB = Fn.begin(), MBBe = Fn.end();
232 MBB != MBBe; ++MBB) {
233 // Find scheduling regions and schedule / packetize each region.
234 unsigned RemainingCount = MBB->size();
235 for(MachineBasicBlock::iterator RegionEnd = MBB->end();
236 RegionEnd != MBB->begin();) {
237 // The next region starts above the previous region. Look backward in the
238 // instruction stream until we find the nearest boundary.
239 MachineBasicBlock::iterator I = RegionEnd;
240 for(;I != MBB->begin(); --I, --RemainingCount) {
241 if (TII->isSchedulingBoundary(std::prev(I), MBB, Fn))
246 // Skip empty scheduling regions.
247 if (I == RegionEnd) {
248 RegionEnd = std::prev(RegionEnd);
252 // Skip regions with one instruction.
253 if (I == std::prev(RegionEnd)) {
254 RegionEnd = std::prev(RegionEnd);
258 Packetizer.PacketizeMIs(MBB, I, RegionEnd);
267 static bool IsIndirectCall(MachineInstr* MI) {
268 return MI->getOpcode() == Hexagon::J2_callr;
271 // Reserve resources for constant extender. Trigure an assertion if
273 void HexagonPacketizerList::reserveResourcesForConstExt(MachineInstr* MI) {
274 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
275 MachineInstr *PseudoMI = MF.CreateMachineInstr(QII->get(Hexagon::A4_ext),
278 if (ResourceTracker->canReserveResources(PseudoMI)) {
279 ResourceTracker->reserveResources(PseudoMI);
280 MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
282 MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
283 llvm_unreachable("can not reserve resources for constant extender.");
288 bool HexagonPacketizerList::canReserveResourcesForConstExt(MachineInstr *MI) {
289 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
290 assert((QII->isExtended(MI) || QII->isConstExtended(MI)) &&
291 "Should only be called for constant extended instructions");
292 MachineInstr *PseudoMI = MF.CreateMachineInstr(QII->get(Hexagon::A4_ext),
294 bool CanReserve = ResourceTracker->canReserveResources(PseudoMI);
295 MF.DeleteMachineInstr(PseudoMI);
299 // Allocate resources (i.e. 4 bytes) for constant extender. If succeed, return
300 // true, otherwise, return false.
301 bool HexagonPacketizerList::tryAllocateResourcesForConstExt(MachineInstr* MI) {
302 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
303 MachineInstr *PseudoMI = MF.CreateMachineInstr(QII->get(Hexagon::A4_ext),
306 if (ResourceTracker->canReserveResources(PseudoMI)) {
307 ResourceTracker->reserveResources(PseudoMI);
308 MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
311 MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
317 bool HexagonPacketizerList::IsCallDependent(MachineInstr* MI,
321 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
322 const HexagonRegisterInfo *QRI =
323 (const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
325 // Check for lr dependence
326 if (DepReg == QRI->getRARegister()) {
330 if (QII->isDeallocRet(MI)) {
331 if (DepReg == QRI->getFrameRegister() ||
332 DepReg == QRI->getStackRegister())
336 // Check if this is a predicate dependence
337 const TargetRegisterClass* RC = QRI->getMinimalPhysRegClass(DepReg);
338 if (RC == &Hexagon::PredRegsRegClass) {
343 // Lastly check for an operand used in an indirect call
344 // If we had an attribute for checking if an instruction is an indirect call,
345 // then we could have avoided this relatively brittle implementation of
348 // Assumes that the first operand of the CALLr is the function address
350 if (IsIndirectCall(MI) && (DepType == SDep::Data)) {
351 MachineOperand MO = MI->getOperand(0);
352 if (MO.isReg() && MO.isUse() && (MO.getReg() == DepReg)) {
360 static bool IsRegDependence(const SDep::Kind DepType) {
361 return (DepType == SDep::Data || DepType == SDep::Anti ||
362 DepType == SDep::Output);
365 static bool IsDirectJump(MachineInstr* MI) {
366 return (MI->getOpcode() == Hexagon::J2_jump);
369 static bool IsSchedBarrier(MachineInstr* MI) {
370 switch (MI->getOpcode()) {
371 case Hexagon::Y2_barrier:
377 static bool IsControlFlow(MachineInstr* MI) {
378 return (MI->getDesc().isTerminator() || MI->getDesc().isCall());
381 static bool IsLoopN(MachineInstr *MI) {
382 return (MI->getOpcode() == Hexagon::J2_loop0i ||
383 MI->getOpcode() == Hexagon::J2_loop0r);
386 /// DoesModifyCalleeSavedReg - Returns true if the instruction modifies a
387 /// callee-saved register.
388 static bool DoesModifyCalleeSavedReg(MachineInstr *MI,
389 const TargetRegisterInfo *TRI) {
390 for (const MCPhysReg *CSR =
391 TRI->getCalleeSavedRegs(MI->getParent()->getParent());
393 unsigned CalleeSavedReg = *CSR;
394 if (MI->modifiesRegister(CalleeSavedReg, TRI))
400 // Returns true if an instruction can be promoted to .new predicate
401 // or new-value store.
402 bool HexagonPacketizerList::isNewifiable(MachineInstr* MI) {
403 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
404 return isCondInst(MI) || QII->mayBeNewStore(MI);
407 bool HexagonPacketizerList::isCondInst (MachineInstr* MI) {
408 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
409 const MCInstrDesc& TID = MI->getDesc();
410 // bug 5670: until that is fixed,
411 // this portion is disabled.
412 if ( TID.isConditionalBranch() // && !IsRegisterJump(MI)) ||
413 || QII->isConditionalTransfer(MI)
414 || QII->isConditionalALU32(MI)
415 || QII->isConditionalLoad(MI)
416 || QII->isConditionalStore(MI)) {
423 // Promote an instructiont to its .new form.
424 // At this time, we have already made a call to CanPromoteToDotNew
425 // and made sure that it can *indeed* be promoted.
426 bool HexagonPacketizerList::PromoteToDotNew(MachineInstr* MI,
427 SDep::Kind DepType, MachineBasicBlock::iterator &MII,
428 const TargetRegisterClass* RC) {
430 assert (DepType == SDep::Data);
431 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
434 if (RC == &Hexagon::PredRegsRegClass)
435 NewOpcode = QII->GetDotNewPredOp(MI, MBPI);
437 NewOpcode = QII->GetDotNewOp(MI);
438 MI->setDesc(QII->get(NewOpcode));
443 bool HexagonPacketizerList::DemoteToDotOld(MachineInstr* MI) {
444 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
445 int NewOpcode = QII->GetDotOldOp(MI->getOpcode());
446 MI->setDesc(QII->get(NewOpcode));
456 /// Returns true if an instruction is predicated on p0 and false if it's
457 /// predicated on !p0.
458 static PredicateKind getPredicateSense(MachineInstr* MI,
459 const HexagonInstrInfo *QII) {
460 if (!QII->isPredicated(MI))
463 if (QII->isPredicatedTrue(MI))
469 static MachineOperand& GetPostIncrementOperand(MachineInstr *MI,
470 const HexagonInstrInfo *QII) {
471 assert(QII->isPostIncrement(MI) && "Not a post increment operation.");
473 // Post Increment means duplicates. Use dense map to find duplicates in the
474 // list. Caution: Densemap initializes with the minimum of 64 buckets,
475 // whereas there are at most 5 operands in the post increment.
476 DenseMap<unsigned, unsigned> DefRegsSet;
477 for(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++)
478 if (MI->getOperand(opNum).isReg() &&
479 MI->getOperand(opNum).isDef()) {
480 DefRegsSet[MI->getOperand(opNum).getReg()] = 1;
483 for(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++)
484 if (MI->getOperand(opNum).isReg() &&
485 MI->getOperand(opNum).isUse()) {
486 if (DefRegsSet[MI->getOperand(opNum).getReg()]) {
487 return MI->getOperand(opNum);
491 if (MI->getDesc().mayLoad()) {
492 // The 2nd operand is always the post increment operand in load.
493 assert(MI->getOperand(1).isReg() &&
494 "Post increment operand has be to a register.");
495 return (MI->getOperand(1));
497 if (MI->getDesc().mayStore()) {
498 // The 1st operand is always the post increment operand in store.
499 assert(MI->getOperand(0).isReg() &&
500 "Post increment operand has be to a register.");
501 return (MI->getOperand(0));
504 // we should never come here.
505 llvm_unreachable("mayLoad or mayStore not set for Post Increment operation");
508 // get the value being stored
509 static MachineOperand& GetStoreValueOperand(MachineInstr *MI) {
510 // value being stored is always the last operand.
511 return (MI->getOperand(MI->getNumOperands()-1));
514 // can be new value store?
515 // Following restrictions are to be respected in convert a store into
516 // a new value store.
517 // 1. If an instruction uses auto-increment, its address register cannot
518 // be a new-value register. Arch Spec 5.4.2.1
519 // 2. If an instruction uses absolute-set addressing mode,
520 // its address register cannot be a new-value register.
521 // Arch Spec 5.4.2.1.TODO: This is not enabled as
522 // as absolute-set address mode patters are not implemented.
523 // 3. If an instruction produces a 64-bit result, its registers cannot be used
524 // as new-value registers. Arch Spec 5.4.2.2.
525 // 4. If the instruction that sets a new-value register is conditional, then
526 // the instruction that uses the new-value register must also be conditional,
527 // and both must always have their predicates evaluate identically.
528 // Arch Spec 5.4.2.3.
529 // 5. There is an implied restriction of a packet can not have another store,
530 // if there is a new value store in the packet. Corollary, if there is
531 // already a store in a packet, there can not be a new value store.
532 // Arch Spec: 3.4.4.2
533 bool HexagonPacketizerList::CanPromoteToNewValueStore(
534 MachineInstr *MI, MachineInstr *PacketMI, unsigned DepReg,
535 const std::map<MachineInstr *, SUnit *> &MIToSUnit) {
536 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
537 // Make sure we are looking at the store, that can be promoted.
538 if (!QII->mayBeNewStore(MI))
541 // Make sure there is dependency and can be new value'ed
542 if (GetStoreValueOperand(MI).isReg() &&
543 GetStoreValueOperand(MI).getReg() != DepReg)
546 const HexagonRegisterInfo *QRI =
547 (const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
548 const MCInstrDesc& MCID = PacketMI->getDesc();
549 // first operand is always the result
551 const TargetRegisterClass* PacketRC = QII->getRegClass(MCID, 0, QRI, MF);
553 // if there is already an store in the packet, no can do new value store
554 // Arch Spec 3.4.4.2.
555 for (std::vector<MachineInstr*>::iterator VI = CurrentPacketMIs.begin(),
556 VE = CurrentPacketMIs.end();
558 SUnit *PacketSU = MIToSUnit.find(*VI)->second;
559 if (PacketSU->getInstr()->getDesc().mayStore() ||
560 // if we have mayStore = 1 set on ALLOCFRAME and DEALLOCFRAME,
561 // then we don't need this
562 PacketSU->getInstr()->getOpcode() == Hexagon::S2_allocframe ||
563 PacketSU->getInstr()->getOpcode() == Hexagon::L2_deallocframe)
567 if (PacketRC == &Hexagon::DoubleRegsRegClass) {
568 // new value store constraint: double regs can not feed into new value store
569 // arch spec section: 5.4.2.2
573 // Make sure it's NOT the post increment register that we are going to
575 if (QII->isPostIncrement(MI) &&
576 MI->getDesc().mayStore() &&
577 GetPostIncrementOperand(MI, QII).getReg() == DepReg) {
581 if (QII->isPostIncrement(PacketMI) &&
582 PacketMI->getDesc().mayLoad() &&
583 GetPostIncrementOperand(PacketMI, QII).getReg() == DepReg) {
584 // if source is post_inc, or absolute-set addressing,
585 // it can not feed into new value store
587 // memw(r30 + #-1404) = r2.new -> can not be new value store
588 // arch spec section: 5.4.2.1
592 // If the source that feeds the store is predicated, new value store must
593 // also be predicated.
594 if (QII->isPredicated(PacketMI)) {
595 if (!QII->isPredicated(MI))
598 // Check to make sure that they both will have their predicates
599 // evaluate identically
600 unsigned predRegNumSrc = 0;
601 unsigned predRegNumDst = 0;
602 const TargetRegisterClass* predRegClass = nullptr;
604 // Get predicate register used in the source instruction
605 for(unsigned opNum = 0; opNum < PacketMI->getNumOperands(); opNum++) {
606 if ( PacketMI->getOperand(opNum).isReg())
607 predRegNumSrc = PacketMI->getOperand(opNum).getReg();
608 predRegClass = QRI->getMinimalPhysRegClass(predRegNumSrc);
609 if (predRegClass == &Hexagon::PredRegsRegClass) {
613 assert ((predRegClass == &Hexagon::PredRegsRegClass ) &&
614 ("predicate register not found in a predicated PacketMI instruction"));
616 // Get predicate register used in new-value store instruction
617 for(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++) {
618 if ( MI->getOperand(opNum).isReg())
619 predRegNumDst = MI->getOperand(opNum).getReg();
620 predRegClass = QRI->getMinimalPhysRegClass(predRegNumDst);
621 if (predRegClass == &Hexagon::PredRegsRegClass) {
625 assert ((predRegClass == &Hexagon::PredRegsRegClass ) &&
626 ("predicate register not found in a predicated MI instruction"));
628 // New-value register producer and user (store) need to satisfy these
630 // 1) Both instructions should be predicated on the same register.
631 // 2) If producer of the new-value register is .new predicated then store
632 // should also be .new predicated and if producer is not .new predicated
633 // then store should not be .new predicated.
634 // 3) Both new-value register producer and user should have same predicate
635 // sense, i.e, either both should be negated or both should be none negated.
637 if (( predRegNumDst != predRegNumSrc) ||
638 QII->isDotNewInst(PacketMI) != QII->isDotNewInst(MI) ||
639 getPredicateSense(MI, QII) != getPredicateSense(PacketMI, QII)) {
644 // Make sure that other than the new-value register no other store instruction
645 // register has been modified in the same packet. Predicate registers can be
646 // modified by they should not be modified between the producer and the store
647 // instruction as it will make them both conditional on different values.
648 // We already know this to be true for all the instructions before and
649 // including PacketMI. Howerver, we need to perform the check for the
650 // remaining instructions in the packet.
652 std::vector<MachineInstr*>::iterator VI;
653 std::vector<MachineInstr*>::iterator VE;
654 unsigned StartCheck = 0;
656 for (VI=CurrentPacketMIs.begin(), VE = CurrentPacketMIs.end();
658 SUnit *TempSU = MIToSUnit.find(*VI)->second;
659 MachineInstr* TempMI = TempSU->getInstr();
661 // Following condition is true for all the instructions until PacketMI is
662 // reached (StartCheck is set to 0 before the for loop).
663 // StartCheck flag is 1 for all the instructions after PacketMI.
664 if (TempMI != PacketMI && !StartCheck) // start processing only after
665 continue; // encountering PacketMI
668 if (TempMI == PacketMI) // We don't want to check PacketMI for dependence
671 for(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++) {
672 if (MI->getOperand(opNum).isReg() &&
673 TempSU->getInstr()->modifiesRegister(MI->getOperand(opNum).getReg(),
679 // Make sure that for non-POST_INC stores:
680 // 1. The only use of reg is DepReg and no other registers.
681 // This handles V4 base+index registers.
682 // The following store can not be dot new.
683 // Eg. r0 = add(r0, #3)a
684 // memw(r1+r0<<#2) = r0
685 if (!QII->isPostIncrement(MI) &&
686 GetStoreValueOperand(MI).isReg() &&
687 GetStoreValueOperand(MI).getReg() == DepReg) {
688 for(unsigned opNum = 0; opNum < MI->getNumOperands()-1; opNum++) {
689 if (MI->getOperand(opNum).isReg() &&
690 MI->getOperand(opNum).getReg() == DepReg) {
694 // 2. If data definition is because of implicit definition of the register,
695 // do not newify the store. Eg.
696 // %R9<def> = ZXTH %R12, %D6<imp-use>, %R12<imp-def>
697 // STrih_indexed %R8, 2, %R12<kill>; mem:ST2[%scevgep343]
698 for(unsigned opNum = 0; opNum < PacketMI->getNumOperands(); opNum++) {
699 if (PacketMI->getOperand(opNum).isReg() &&
700 PacketMI->getOperand(opNum).getReg() == DepReg &&
701 PacketMI->getOperand(opNum).isDef() &&
702 PacketMI->getOperand(opNum).isImplicit()) {
708 // Can be dot new store.
712 // can this MI to promoted to either
713 // new value store or new value jump
714 bool HexagonPacketizerList::CanPromoteToNewValue(
715 MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
716 const std::map<MachineInstr *, SUnit *> &MIToSUnit,
717 MachineBasicBlock::iterator &MII) {
719 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
720 if (!QII->mayBeNewStore(MI))
723 MachineInstr *PacketMI = PacketSU->getInstr();
725 // Check to see the store can be new value'ed.
726 if (CanPromoteToNewValueStore(MI, PacketMI, DepReg, MIToSUnit))
729 // Check to see the compare/jump can be new value'ed.
730 // This is done as a pass on its own. Don't need to check it here.
734 // Check to see if an instruction can be dot new
735 // There are three kinds.
736 // 1. dot new on predicate - V2/V3/V4
737 // 2. dot new on stores NV/ST - V4
738 // 3. dot new on jump NV/J - V4 -- This is generated in a pass.
739 bool HexagonPacketizerList::CanPromoteToDotNew(
740 MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
741 const std::map<MachineInstr *, SUnit *> &MIToSUnit,
742 MachineBasicBlock::iterator &MII, const TargetRegisterClass *RC) {
743 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
744 // Already a dot new instruction.
745 if (QII->isDotNewInst(MI) && !QII->mayBeNewStore(MI))
748 if (!isNewifiable(MI))
752 if (RC == &Hexagon::PredRegsRegClass && isCondInst(MI))
754 else if (RC != &Hexagon::PredRegsRegClass &&
755 !QII->mayBeNewStore(MI)) // MI is not a new-value store
758 // Create a dot new machine instruction to see if resources can be
759 // allocated. If not, bail out now.
760 int NewOpcode = QII->GetDotNewOp(MI);
761 const MCInstrDesc &desc = QII->get(NewOpcode);
763 MachineInstr *NewMI =
764 MI->getParent()->getParent()->CreateMachineInstr(desc, dl);
765 bool ResourcesAvailable = ResourceTracker->canReserveResources(NewMI);
766 MI->getParent()->getParent()->DeleteMachineInstr(NewMI);
768 if (!ResourcesAvailable)
771 // new value store only
772 // new new value jump generated as a passes
773 if (!CanPromoteToNewValue(MI, PacketSU, DepReg, MIToSUnit, MII)) {
780 // Go through the packet instructions and search for anti dependency
781 // between them and DepReg from MI
782 // Consider this case:
784 // a) %R1<def> = TFRI_cdNotPt %P3, 2
787 // b) %P0<def> = OR_pp %P3<kill>, %P0<kill>
788 // c) %P3<def> = TFR_PdRs %R23
789 // d) %R1<def> = TFRI_cdnPt %P3, 4
791 // The P3 from a) and d) will be complements after
792 // a)'s P3 is converted to .new form
793 // Anti Dep between c) and b) is irrelevant for this case
794 bool HexagonPacketizerList::RestrictingDepExistInPacket(
795 MachineInstr *MI, unsigned DepReg,
796 const std::map<MachineInstr *, SUnit *> &MIToSUnit) {
798 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
799 SUnit *PacketSUDep = MIToSUnit.find(MI)->second;
801 for (std::vector<MachineInstr*>::iterator VIN = CurrentPacketMIs.begin(),
802 VEN = CurrentPacketMIs.end(); (VIN != VEN); ++VIN) {
804 // We only care for dependencies to predicated instructions
805 if(!QII->isPredicated(*VIN)) continue;
807 // Scheduling Unit for current insn in the packet
808 SUnit *PacketSU = MIToSUnit.find(*VIN)->second;
810 // Look at dependencies between current members of the packet
811 // and predicate defining instruction MI.
812 // Make sure that dependency is on the exact register
814 if (PacketSU->isSucc(PacketSUDep)) {
815 for (unsigned i = 0; i < PacketSU->Succs.size(); ++i) {
816 if ((PacketSU->Succs[i].getSUnit() == PacketSUDep) &&
817 (PacketSU->Succs[i].getKind() == SDep::Anti) &&
818 (PacketSU->Succs[i].getReg() == DepReg)) {
829 /// Gets the predicate register of a predicated instruction.
830 static unsigned getPredicatedRegister(MachineInstr *MI,
831 const HexagonInstrInfo *QII) {
832 /// We use the following rule: The first predicate register that is a use is
833 /// the predicate register of a predicated instruction.
835 assert(QII->isPredicated(MI) && "Must be predicated instruction");
837 for (MachineInstr::mop_iterator OI = MI->operands_begin(),
838 OE = MI->operands_end(); OI != OE; ++OI) {
839 MachineOperand &Op = *OI;
840 if (Op.isReg() && Op.getReg() && Op.isUse() &&
841 Hexagon::PredRegsRegClass.contains(Op.getReg()))
845 llvm_unreachable("Unknown instruction operand layout");
850 // Given two predicated instructions, this function detects whether
851 // the predicates are complements
852 bool HexagonPacketizerList::ArePredicatesComplements(
853 MachineInstr *MI1, MachineInstr *MI2,
854 const std::map<MachineInstr *, SUnit *> &MIToSUnit) {
856 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
858 // If we don't know the predicate sense of the instructions bail out early, we
860 if (getPredicateSense(MI1, QII) == PK_Unknown ||
861 getPredicateSense(MI2, QII) == PK_Unknown)
864 // Scheduling unit for candidate
865 SUnit *SU = MIToSUnit.find(MI1)->second;
867 // One corner case deals with the following scenario:
869 // a) %R24<def> = TFR_cPt %P0, %R25
873 // b) %R25<def> = TFR_cNotPt %P0, %R24
874 // c) %P0<def> = CMPEQri %R26, 1
877 // On general check a) and b) are complements, but
878 // presence of c) will convert a) to .new form, and
879 // then it is not a complement
880 // We attempt to detect it by analyzing existing
881 // dependencies in the packet
883 // Analyze relationships between all existing members of the packet.
884 // Look for Anti dependecy on the same predicate reg
885 // as used in the candidate
886 for (std::vector<MachineInstr*>::iterator VIN = CurrentPacketMIs.begin(),
887 VEN = CurrentPacketMIs.end(); (VIN != VEN); ++VIN) {
889 // Scheduling Unit for current insn in the packet
890 SUnit *PacketSU = MIToSUnit.find(*VIN)->second;
892 // If this instruction in the packet is succeeded by the candidate...
893 if (PacketSU->isSucc(SU)) {
894 for (unsigned i = 0; i < PacketSU->Succs.size(); ++i) {
895 // The corner case exist when there is true data
896 // dependency between candidate and one of current
897 // packet members, this dep is on predicate reg, and
898 // there already exist anti dep on the same pred in
900 if (PacketSU->Succs[i].getSUnit() == SU &&
901 PacketSU->Succs[i].getKind() == SDep::Data &&
902 Hexagon::PredRegsRegClass.contains(
903 PacketSU->Succs[i].getReg()) &&
904 // Here I know that *VIN is predicate setting instruction
905 // with true data dep to candidate on the register
906 // we care about - c) in the above example.
907 // Now I need to see if there is an anti dependency
908 // from c) to any other instruction in the
909 // same packet on the pred reg of interest
910 RestrictingDepExistInPacket(*VIN,PacketSU->Succs[i].getReg(),
918 // If the above case does not apply, check regular
919 // complement condition.
920 // Check that the predicate register is the same and
921 // that the predicate sense is different
922 // We also need to differentiate .old vs. .new:
923 // !p0 is not complimentary to p0.new
924 unsigned PReg1 = getPredicatedRegister(MI1, QII);
925 unsigned PReg2 = getPredicatedRegister(MI2, QII);
926 return ((PReg1 == PReg2) &&
927 Hexagon::PredRegsRegClass.contains(PReg1) &&
928 Hexagon::PredRegsRegClass.contains(PReg2) &&
929 (getPredicateSense(MI1, QII) != getPredicateSense(MI2, QII)) &&
930 (QII->isDotNewInst(MI1) == QII->isDotNewInst(MI2)));
933 // initPacketizerState - Initialize packetizer flags
934 void HexagonPacketizerList::initPacketizerState() {
937 PromotedToDotNew = false;
938 GlueToNewValueJump = false;
939 GlueAllocframeStore = false;
940 FoundSequentialDependence = false;
945 // ignorePseudoInstruction - Ignore bundling of pseudo instructions.
946 bool HexagonPacketizerList::ignorePseudoInstruction(MachineInstr *MI,
947 MachineBasicBlock *MBB) {
948 if (MI->isDebugValue())
951 if (MI->isCFIInstruction())
954 // We must print out inline assembly
955 if (MI->isInlineAsm())
958 // We check if MI has any functional units mapped to it.
959 // If it doesn't, we ignore the instruction.
960 const MCInstrDesc& TID = MI->getDesc();
961 unsigned SchedClass = TID.getSchedClass();
962 const InstrStage* IS =
963 ResourceTracker->getInstrItins()->beginStage(SchedClass);
964 unsigned FuncUnits = IS->getUnits();
968 // isSoloInstruction: - Returns true for instructions that must be
969 // scheduled in their own packet.
970 bool HexagonPacketizerList::isSoloInstruction(MachineInstr *MI) {
971 if (MI->isEHLabel() || MI->isCFIInstruction())
974 if (MI->isInlineAsm())
977 // From Hexagon V4 Programmer's Reference Manual 3.4.4 Grouping constraints:
978 // trap, pause, barrier, icinva, isync, and syncht are solo instructions.
979 // They must not be grouped with other instructions in a packet.
980 if (IsSchedBarrier(MI))
986 // isLegalToPacketizeTogether:
987 // SUI is the current instruction that is out side of the current packet.
988 // SUJ is the current instruction inside the current packet against which that
989 // SUI will be packetized.
990 bool HexagonPacketizerList::isLegalToPacketizeTogether(SUnit *SUI, SUnit *SUJ) {
991 MachineInstr *I = SUI->getInstr();
992 MachineInstr *J = SUJ->getInstr();
993 assert(I && J && "Unable to packetize null instruction!");
995 const MCInstrDesc &MCIDI = I->getDesc();
996 const MCInstrDesc &MCIDJ = J->getDesc();
998 MachineBasicBlock::iterator II = I;
1000 const unsigned FrameSize = MF.getFrameInfo()->getStackSize();
1001 const HexagonRegisterInfo *QRI =
1002 (const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
1003 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
1005 // Inline asm cannot go in the packet.
1006 if (I->getOpcode() == Hexagon::INLINEASM)
1007 llvm_unreachable("Should not meet inline asm here!");
1009 if (isSoloInstruction(I))
1010 llvm_unreachable("Should not meet solo instr here!");
1012 // A save callee-save register function call can only be in a packet
1013 // with instructions that don't write to the callee-save registers.
1014 if ((QII->isSaveCalleeSavedRegsCall(I) &&
1015 DoesModifyCalleeSavedReg(J, QRI)) ||
1016 (QII->isSaveCalleeSavedRegsCall(J) &&
1017 DoesModifyCalleeSavedReg(I, QRI))) {
1022 // Two control flow instructions cannot go in the same packet.
1023 if (IsControlFlow(I) && IsControlFlow(J)) {
1028 // A LoopN instruction cannot appear in the same packet as a jump or call.
1030 (IsDirectJump(J) || MCIDJ.isCall() || QII->isDeallocRet(J))) {
1035 (IsDirectJump(I) || MCIDI.isCall() || QII->isDeallocRet(I))) {
1040 // dealloc_return cannot appear in the same packet as a conditional or
1041 // unconditional jump.
1042 if (QII->isDeallocRet(I) &&
1043 (MCIDJ.isBranch() || MCIDJ.isCall() || MCIDJ.isBarrier())) {
1049 // V4 allows dual store. But does not allow second store, if the
1050 // first store is not in SLOT0. New value store, new value jump,
1051 // dealloc_return and memop always take SLOT0.
1052 // Arch spec 3.4.4.2
1053 if (MCIDI.mayStore() && MCIDJ.mayStore() &&
1054 (QII->isNewValueInst(J) || QII->isMemOp(J) || QII->isMemOp(I))) {
1059 if ((QII->isMemOp(J) && MCIDI.mayStore())
1060 || (MCIDJ.mayStore() && QII->isMemOp(I))
1061 || (QII->isMemOp(J) && QII->isMemOp(I))) {
1067 if (MCIDJ.mayStore() && QII->isDeallocRet(I)) {
1072 // If an instruction feeds new value jump, glue it.
1073 MachineBasicBlock::iterator NextMII = I;
1075 if (NextMII != I->getParent()->end() && QII->isNewValueJump(NextMII)) {
1076 MachineInstr *NextMI = NextMII;
1078 bool secondRegMatch = false;
1079 bool maintainNewValueJump = false;
1081 if (NextMI->getOperand(1).isReg() &&
1082 I->getOperand(0).getReg() == NextMI->getOperand(1).getReg()) {
1083 secondRegMatch = true;
1084 maintainNewValueJump = true;
1087 if (!secondRegMatch &&
1088 I->getOperand(0).getReg() == NextMI->getOperand(0).getReg()) {
1089 maintainNewValueJump = true;
1092 for (std::vector<MachineInstr*>::iterator
1093 VI = CurrentPacketMIs.begin(),
1094 VE = CurrentPacketMIs.end();
1095 (VI != VE && maintainNewValueJump); ++VI) {
1096 SUnit *PacketSU = MIToSUnit.find(*VI)->second;
1098 // NVJ can not be part of the dual jump - Arch Spec: section 7.8
1099 if (PacketSU->getInstr()->getDesc().isCall()) {
1104 // 1. Packet does not have a store in it.
1105 // 2. If the first operand of the nvj is newified, and the second
1106 // operand is also a reg, it (second reg) is not defined in
1108 // 3. If the second operand of the nvj is newified, (which means
1109 // first operand is also a reg), first reg is not defined in
1111 if (PacketSU->getInstr()->getDesc().mayStore() ||
1112 PacketSU->getInstr()->getOpcode() == Hexagon::S2_allocframe ||
1114 (!secondRegMatch && NextMI->getOperand(1).isReg() &&
1115 PacketSU->getInstr()->modifiesRegister(
1116 NextMI->getOperand(1).getReg(), QRI)) ||
1119 PacketSU->getInstr()->modifiesRegister(
1120 NextMI->getOperand(0).getReg(), QRI))) {
1126 GlueToNewValueJump = true;
1131 if (SUJ->isSucc(SUI)) {
1132 for (unsigned i = 0;
1133 (i < SUJ->Succs.size()) && !FoundSequentialDependence;
1136 if (SUJ->Succs[i].getSUnit() != SUI) {
1140 SDep::Kind DepType = SUJ->Succs[i].getKind();
1142 // For direct calls:
1143 // Ignore register dependences for call instructions for
1144 // packetization purposes except for those due to r31 and
1145 // predicate registers.
1147 // For indirect calls:
1148 // Same as direct calls + check for true dependences to the register
1149 // used in the indirect call.
1151 // We completely ignore Order dependences for call instructions
1154 // Ignore register dependences for return instructions like jumpr,
1155 // dealloc return unless we have dependencies on the explicit uses
1156 // of the registers used by jumpr (like r31) or dealloc return
1157 // (like r29 or r30).
1159 // TODO: Currently, jumpr is handling only return of r31. So, the
1160 // following logic (specificaly IsCallDependent) is working fine.
1161 // We need to enable jumpr for register other than r31 and then,
1162 // we need to rework the last part, where it handles indirect call
1163 // of that (IsCallDependent) function. Bug 6216 is opened for this.
1165 unsigned DepReg = 0;
1166 const TargetRegisterClass* RC = nullptr;
1167 if (DepType == SDep::Data) {
1168 DepReg = SUJ->Succs[i].getReg();
1169 RC = QRI->getMinimalPhysRegClass(DepReg);
1171 if ((MCIDI.isCall() || MCIDI.isReturn()) &&
1172 (!IsRegDependence(DepType) ||
1173 !IsCallDependent(I, DepType, SUJ->Succs[i].getReg()))) {
1177 // For instructions that can be promoted to dot-new, try to promote.
1178 else if ((DepType == SDep::Data) &&
1179 CanPromoteToDotNew(I, SUJ, DepReg, MIToSUnit, II, RC) &&
1180 PromoteToDotNew(I, DepType, II, RC)) {
1181 PromotedToDotNew = true;
1185 else if ((DepType == SDep::Data) &&
1186 (QII->isNewValueJump(I))) {
1190 // For predicated instructions, if the predicates are complements
1191 // then there can be no dependence.
1192 else if (QII->isPredicated(I) &&
1193 QII->isPredicated(J) &&
1194 ArePredicatesComplements(I, J, MIToSUnit)) {
1198 else if (IsDirectJump(I) &&
1199 !MCIDJ.isBranch() &&
1201 (DepType == SDep::Order)) {
1202 // Ignore Order dependences between unconditional direct branches
1203 // and non-control-flow instructions
1206 else if (MCIDI.isConditionalBranch() && (DepType != SDep::Data) &&
1207 (DepType != SDep::Output)) {
1208 // Ignore all dependences for jumps except for true and output
1213 // Ignore output dependences due to superregs. We can
1214 // write to two different subregisters of R1:0 for instance
1215 // in the same cycle
1220 // If neither I nor J defines DepReg, then this is a
1221 // superfluous output dependence. The dependence must be of the
1225 // and there is an output dependence between the two instructions
1228 // We want to ignore these dependences.
1229 // Ideally, the dependence constructor should annotate such
1230 // dependences. We can then avoid this relatively expensive check.
1232 else if (DepType == SDep::Output) {
1233 // DepReg is the register that's responsible for the dependence.
1234 unsigned DepReg = SUJ->Succs[i].getReg();
1236 // Check if I and J really defines DepReg.
1237 if (I->definesRegister(DepReg) ||
1238 J->definesRegister(DepReg)) {
1239 FoundSequentialDependence = true;
1244 // We ignore Order dependences for
1245 // 1. Two loads unless they are volatile.
1246 // 2. Two stores in V4 unless they are volatile.
1247 else if ((DepType == SDep::Order) &&
1248 !I->hasOrderedMemoryRef() &&
1249 !J->hasOrderedMemoryRef()) {
1250 if (MCIDI.mayStore() && MCIDJ.mayStore()) {
1253 // store followed by store-- not OK on V2
1254 // store followed by load -- not OK on all (OK if addresses
1256 // load followed by store -- OK on all
1257 // load followed by load -- OK on all
1258 else if ( !MCIDJ.mayStore()) {
1262 FoundSequentialDependence = true;
1267 // For V4, special case ALLOCFRAME. Even though there is dependency
1268 // between ALLOCFRAME and subsequent store, allow it to be
1269 // packetized in a same packet. This implies that the store is using
1270 // caller's SP. Hence, offset needs to be updated accordingly.
1271 else if (DepType == SDep::Data
1272 && J->getOpcode() == Hexagon::S2_allocframe
1273 && (I->getOpcode() == Hexagon::S2_storerd_io
1274 || I->getOpcode() == Hexagon::S2_storeri_io
1275 || I->getOpcode() == Hexagon::S2_storerb_io)
1276 && I->getOperand(0).getReg() == QRI->getStackRegister()
1277 && QII->isValidOffset(I->getOpcode(),
1278 I->getOperand(1).getImm() -
1279 (FrameSize + HEXAGON_LRFP_SIZE)))
1281 GlueAllocframeStore = true;
1282 // Since this store is to be glued with allocframe in the same
1283 // packet, it will use SP of the previous stack frame, i.e
1284 // caller's SP. Therefore, we need to recalculate offset according
1286 I->getOperand(1).setImm(I->getOperand(1).getImm() -
1287 (FrameSize + HEXAGON_LRFP_SIZE));
1291 // Skip over anti-dependences. Two instructions that are
1292 // anti-dependent can share a packet
1294 else if (DepType != SDep::Anti) {
1295 FoundSequentialDependence = true;
1300 if (FoundSequentialDependence) {
1309 // isLegalToPruneDependencies
1310 bool HexagonPacketizerList::isLegalToPruneDependencies(SUnit *SUI, SUnit *SUJ) {
1311 MachineInstr *I = SUI->getInstr();
1312 assert(I && SUJ->getInstr() && "Unable to packetize null instruction!");
1314 const unsigned FrameSize = MF.getFrameInfo()->getStackSize();
1318 // Check if the instruction was promoted to a dot-new. If so, demote it
1319 // back into a dot-old.
1320 if (PromotedToDotNew) {
1324 // Check if the instruction (must be a store) was glued with an Allocframe
1325 // instruction. If so, restore its offset to its original value, i.e. use
1326 // curent SP instead of caller's SP.
1327 if (GlueAllocframeStore) {
1328 I->getOperand(1).setImm(I->getOperand(1).getImm() +
1329 FrameSize + HEXAGON_LRFP_SIZE);
1337 MachineBasicBlock::iterator
1338 HexagonPacketizerList::addToPacket(MachineInstr *MI) {
1340 MachineBasicBlock::iterator MII = MI;
1341 MachineBasicBlock *MBB = MI->getParent();
1343 const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
1345 if (GlueToNewValueJump) {
1348 MachineInstr *nvjMI = MII;
1349 assert(ResourceTracker->canReserveResources(MI));
1350 ResourceTracker->reserveResources(MI);
1351 if ((QII->isExtended(MI) || QII->isConstExtended(MI)) &&
1352 !tryAllocateResourcesForConstExt(MI)) {
1354 ResourceTracker->reserveResources(MI);
1355 assert(canReserveResourcesForConstExt(MI) &&
1356 "Ensure that there is a slot");
1357 reserveResourcesForConstExt(MI);
1358 // Reserve resources for new value jump constant extender.
1359 assert(canReserveResourcesForConstExt(MI) &&
1360 "Ensure that there is a slot");
1361 reserveResourcesForConstExt(nvjMI);
1362 assert(ResourceTracker->canReserveResources(nvjMI) &&
1363 "Ensure that there is a slot");
1365 } else if ( // Extended instruction takes two slots in the packet.
1366 // Try reserve and allocate 4-byte in the current packet first.
1367 (QII->isExtended(nvjMI)
1368 && (!tryAllocateResourcesForConstExt(nvjMI)
1369 || !ResourceTracker->canReserveResources(nvjMI)))
1370 || // For non-extended instruction, no need to allocate extra 4 bytes.
1371 (!QII->isExtended(nvjMI) &&
1372 !ResourceTracker->canReserveResources(nvjMI)))
1375 // A new and empty packet starts.
1376 // We are sure that the resources requirements can be satisfied.
1377 // Therefore, do not need to call "canReserveResources" anymore.
1378 ResourceTracker->reserveResources(MI);
1379 if (QII->isExtended(nvjMI))
1380 reserveResourcesForConstExt(nvjMI);
1382 // Here, we are sure that "reserveResources" would succeed.
1383 ResourceTracker->reserveResources(nvjMI);
1384 CurrentPacketMIs.push_back(MI);
1385 CurrentPacketMIs.push_back(nvjMI);
1387 if ( (QII->isExtended(MI) || QII->isConstExtended(MI))
1388 && ( !tryAllocateResourcesForConstExt(MI)
1389 || !ResourceTracker->canReserveResources(MI)))
1392 // Check if the instruction was promoted to a dot-new. If so, demote it
1393 // back into a dot-old
1394 if (PromotedToDotNew) {
1397 reserveResourcesForConstExt(MI);
1399 // In case that "MI" is not an extended insn,
1400 // the resource availability has already been checked.
1401 ResourceTracker->reserveResources(MI);
1402 CurrentPacketMIs.push_back(MI);
1407 //===----------------------------------------------------------------------===//
1408 // Public Constructor Functions
1409 //===----------------------------------------------------------------------===//
1411 FunctionPass *llvm::createHexagonPacketizer() {
1412 return new HexagonPacketizer();