1 //===- lib/CodeGen/MachineTraceMetrics.cpp --------------------------------===//
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 #include "llvm/CodeGen/MachineTraceMetrics.h"
11 #include "llvm/ADT/ArrayRef.h"
12 #include "llvm/ADT/DenseMap.h"
13 #include "llvm/ADT/Optional.h"
14 #include "llvm/ADT/PostOrderIterator.h"
15 #include "llvm/ADT/SmallPtrSet.h"
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/ADT/SparseSet.h"
18 #include "llvm/CodeGen/MachineBasicBlock.h"
19 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
20 #include "llvm/CodeGen/MachineFunction.h"
21 #include "llvm/CodeGen/MachineInstr.h"
22 #include "llvm/CodeGen/MachineLoopInfo.h"
23 #include "llvm/CodeGen/MachineOperand.h"
24 #include "llvm/CodeGen/MachineRegisterInfo.h"
25 #include "llvm/CodeGen/TargetRegisterInfo.h"
26 #include "llvm/CodeGen/TargetSchedule.h"
27 #include "llvm/CodeGen/TargetSubtargetInfo.h"
28 #include "llvm/MC/MCRegisterInfo.h"
29 #include "llvm/Pass.h"
30 #include "llvm/Support/Debug.h"
31 #include "llvm/Support/ErrorHandling.h"
32 #include "llvm/Support/Format.h"
33 #include "llvm/Support/raw_ostream.h"
42 #define DEBUG_TYPE "machine-trace-metrics"
44 char MachineTraceMetrics::ID = 0;
46 char &llvm::MachineTraceMetricsID = MachineTraceMetrics::ID;
48 INITIALIZE_PASS_BEGIN(MachineTraceMetrics, DEBUG_TYPE,
49 "Machine Trace Metrics", false, true)
50 INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
51 INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
52 INITIALIZE_PASS_END(MachineTraceMetrics, DEBUG_TYPE,
53 "Machine Trace Metrics", false, true)
55 MachineTraceMetrics::MachineTraceMetrics() : MachineFunctionPass(ID) {
56 std::fill(std::begin(Ensembles), std::end(Ensembles), nullptr);
59 void MachineTraceMetrics::getAnalysisUsage(AnalysisUsage &AU) const {
61 AU.addRequired<MachineBranchProbabilityInfo>();
62 AU.addRequired<MachineLoopInfo>();
63 MachineFunctionPass::getAnalysisUsage(AU);
66 bool MachineTraceMetrics::runOnMachineFunction(MachineFunction &Func) {
68 const TargetSubtargetInfo &ST = MF->getSubtarget();
69 TII = ST.getInstrInfo();
70 TRI = ST.getRegisterInfo();
71 MRI = &MF->getRegInfo();
72 Loops = &getAnalysis<MachineLoopInfo>();
74 BlockInfo.resize(MF->getNumBlockIDs());
75 ProcResourceCycles.resize(MF->getNumBlockIDs() *
76 SchedModel.getNumProcResourceKinds());
80 void MachineTraceMetrics::releaseMemory() {
83 for (unsigned i = 0; i != TS_NumStrategies; ++i) {
85 Ensembles[i] = nullptr;
89 //===----------------------------------------------------------------------===//
90 // Fixed block information
91 //===----------------------------------------------------------------------===//
93 // The number of instructions in a basic block and the CPU resources used by
94 // those instructions don't depend on any given trace strategy.
96 /// Compute the resource usage in basic block MBB.
97 const MachineTraceMetrics::FixedBlockInfo*
98 MachineTraceMetrics::getResources(const MachineBasicBlock *MBB) {
99 assert(MBB && "No basic block");
100 FixedBlockInfo *FBI = &BlockInfo[MBB->getNumber()];
101 if (FBI->hasResources())
104 // Compute resource usage in the block.
105 FBI->HasCalls = false;
106 unsigned InstrCount = 0;
108 // Add up per-processor resource cycles as well.
109 unsigned PRKinds = SchedModel.getNumProcResourceKinds();
110 SmallVector<unsigned, 32> PRCycles(PRKinds);
112 for (const auto &MI : *MBB) {
113 if (MI.isTransient())
117 FBI->HasCalls = true;
119 // Count processor resources used.
120 if (!SchedModel.hasInstrSchedModel())
122 const MCSchedClassDesc *SC = SchedModel.resolveSchedClass(&MI);
126 for (TargetSchedModel::ProcResIter
127 PI = SchedModel.getWriteProcResBegin(SC),
128 PE = SchedModel.getWriteProcResEnd(SC); PI != PE; ++PI) {
129 assert(PI->ProcResourceIdx < PRKinds && "Bad processor resource kind");
130 PRCycles[PI->ProcResourceIdx] += PI->Cycles;
133 FBI->InstrCount = InstrCount;
135 // Scale the resource cycles so they are comparable.
136 unsigned PROffset = MBB->getNumber() * PRKinds;
137 for (unsigned K = 0; K != PRKinds; ++K)
138 ProcResourceCycles[PROffset + K] =
139 PRCycles[K] * SchedModel.getResourceFactor(K);
145 MachineTraceMetrics::getProcResourceCycles(unsigned MBBNum) const {
146 assert(BlockInfo[MBBNum].hasResources() &&
147 "getResources() must be called before getProcResourceCycles()");
148 unsigned PRKinds = SchedModel.getNumProcResourceKinds();
149 assert((MBBNum+1) * PRKinds <= ProcResourceCycles.size());
150 return makeArrayRef(ProcResourceCycles.data() + MBBNum * PRKinds, PRKinds);
153 //===----------------------------------------------------------------------===//
154 // Ensemble utility functions
155 //===----------------------------------------------------------------------===//
157 MachineTraceMetrics::Ensemble::Ensemble(MachineTraceMetrics *ct)
159 BlockInfo.resize(MTM.BlockInfo.size());
160 unsigned PRKinds = MTM.SchedModel.getNumProcResourceKinds();
161 ProcResourceDepths.resize(MTM.BlockInfo.size() * PRKinds);
162 ProcResourceHeights.resize(MTM.BlockInfo.size() * PRKinds);
165 // Virtual destructor serves as an anchor.
166 MachineTraceMetrics::Ensemble::~Ensemble() = default;
169 MachineTraceMetrics::Ensemble::getLoopFor(const MachineBasicBlock *MBB) const {
170 return MTM.Loops->getLoopFor(MBB);
173 // Update resource-related information in the TraceBlockInfo for MBB.
174 // Only update resources related to the trace above MBB.
175 void MachineTraceMetrics::Ensemble::
176 computeDepthResources(const MachineBasicBlock *MBB) {
177 TraceBlockInfo *TBI = &BlockInfo[MBB->getNumber()];
178 unsigned PRKinds = MTM.SchedModel.getNumProcResourceKinds();
179 unsigned PROffset = MBB->getNumber() * PRKinds;
181 // Compute resources from trace above. The top block is simple.
184 TBI->Head = MBB->getNumber();
185 std::fill(ProcResourceDepths.begin() + PROffset,
186 ProcResourceDepths.begin() + PROffset + PRKinds, 0);
190 // Compute from the block above. A post-order traversal ensures the
191 // predecessor is always computed first.
192 unsigned PredNum = TBI->Pred->getNumber();
193 TraceBlockInfo *PredTBI = &BlockInfo[PredNum];
194 assert(PredTBI->hasValidDepth() && "Trace above has not been computed yet");
195 const FixedBlockInfo *PredFBI = MTM.getResources(TBI->Pred);
196 TBI->InstrDepth = PredTBI->InstrDepth + PredFBI->InstrCount;
197 TBI->Head = PredTBI->Head;
199 // Compute per-resource depths.
200 ArrayRef<unsigned> PredPRDepths = getProcResourceDepths(PredNum);
201 ArrayRef<unsigned> PredPRCycles = MTM.getProcResourceCycles(PredNum);
202 for (unsigned K = 0; K != PRKinds; ++K)
203 ProcResourceDepths[PROffset + K] = PredPRDepths[K] + PredPRCycles[K];
206 // Update resource-related information in the TraceBlockInfo for MBB.
207 // Only update resources related to the trace below MBB.
208 void MachineTraceMetrics::Ensemble::
209 computeHeightResources(const MachineBasicBlock *MBB) {
210 TraceBlockInfo *TBI = &BlockInfo[MBB->getNumber()];
211 unsigned PRKinds = MTM.SchedModel.getNumProcResourceKinds();
212 unsigned PROffset = MBB->getNumber() * PRKinds;
214 // Compute resources for the current block.
215 TBI->InstrHeight = MTM.getResources(MBB)->InstrCount;
216 ArrayRef<unsigned> PRCycles = MTM.getProcResourceCycles(MBB->getNumber());
218 // The trace tail is done.
220 TBI->Tail = MBB->getNumber();
221 std::copy(PRCycles.begin(), PRCycles.end(),
222 ProcResourceHeights.begin() + PROffset);
226 // Compute from the block below. A post-order traversal ensures the
227 // predecessor is always computed first.
228 unsigned SuccNum = TBI->Succ->getNumber();
229 TraceBlockInfo *SuccTBI = &BlockInfo[SuccNum];
230 assert(SuccTBI->hasValidHeight() && "Trace below has not been computed yet");
231 TBI->InstrHeight += SuccTBI->InstrHeight;
232 TBI->Tail = SuccTBI->Tail;
234 // Compute per-resource heights.
235 ArrayRef<unsigned> SuccPRHeights = getProcResourceHeights(SuccNum);
236 for (unsigned K = 0; K != PRKinds; ++K)
237 ProcResourceHeights[PROffset + K] = SuccPRHeights[K] + PRCycles[K];
240 // Check if depth resources for MBB are valid and return the TBI.
241 // Return NULL if the resources have been invalidated.
242 const MachineTraceMetrics::TraceBlockInfo*
243 MachineTraceMetrics::Ensemble::
244 getDepthResources(const MachineBasicBlock *MBB) const {
245 const TraceBlockInfo *TBI = &BlockInfo[MBB->getNumber()];
246 return TBI->hasValidDepth() ? TBI : nullptr;
249 // Check if height resources for MBB are valid and return the TBI.
250 // Return NULL if the resources have been invalidated.
251 const MachineTraceMetrics::TraceBlockInfo*
252 MachineTraceMetrics::Ensemble::
253 getHeightResources(const MachineBasicBlock *MBB) const {
254 const TraceBlockInfo *TBI = &BlockInfo[MBB->getNumber()];
255 return TBI->hasValidHeight() ? TBI : nullptr;
258 /// Get an array of processor resource depths for MBB. Indexed by processor
259 /// resource kind, this array contains the scaled processor resources consumed
260 /// by all blocks preceding MBB in its trace. It does not include instructions
263 /// Compare TraceBlockInfo::InstrDepth.
265 MachineTraceMetrics::Ensemble::
266 getProcResourceDepths(unsigned MBBNum) const {
267 unsigned PRKinds = MTM.SchedModel.getNumProcResourceKinds();
268 assert((MBBNum+1) * PRKinds <= ProcResourceDepths.size());
269 return makeArrayRef(ProcResourceDepths.data() + MBBNum * PRKinds, PRKinds);
272 /// Get an array of processor resource heights for MBB. Indexed by processor
273 /// resource kind, this array contains the scaled processor resources consumed
274 /// by this block and all blocks following it in its trace.
276 /// Compare TraceBlockInfo::InstrHeight.
278 MachineTraceMetrics::Ensemble::
279 getProcResourceHeights(unsigned MBBNum) const {
280 unsigned PRKinds = MTM.SchedModel.getNumProcResourceKinds();
281 assert((MBBNum+1) * PRKinds <= ProcResourceHeights.size());
282 return makeArrayRef(ProcResourceHeights.data() + MBBNum * PRKinds, PRKinds);
285 //===----------------------------------------------------------------------===//
286 // Trace Selection Strategies
287 //===----------------------------------------------------------------------===//
289 // A trace selection strategy is implemented as a sub-class of Ensemble. The
290 // trace through a block B is computed by two DFS traversals of the CFG
291 // starting from B. One upwards, and one downwards. During the upwards DFS,
292 // pickTracePred() is called on the post-ordered blocks. During the downwards
293 // DFS, pickTraceSucc() is called in a post-order.
296 // We never allow traces that leave loops, but we do allow traces to enter
297 // nested loops. We also never allow traces to contain back-edges.
299 // This means that a loop header can never appear above the center block of a
300 // trace, except as the trace head. Below the center block, loop exiting edges
303 // Return true if an edge from the From loop to the To loop is leaving a loop.
304 // Either of To and From can be null.
305 static bool isExitingLoop(const MachineLoop *From, const MachineLoop *To) {
306 return From && !From->contains(To);
309 // MinInstrCountEnsemble - Pick the trace that executes the least number of
313 class MinInstrCountEnsemble : public MachineTraceMetrics::Ensemble {
314 const char *getName() const override { return "MinInstr"; }
315 const MachineBasicBlock *pickTracePred(const MachineBasicBlock*) override;
316 const MachineBasicBlock *pickTraceSucc(const MachineBasicBlock*) override;
319 MinInstrCountEnsemble(MachineTraceMetrics *mtm)
320 : MachineTraceMetrics::Ensemble(mtm) {}
323 } // end anonymous namespace
325 // Select the preferred predecessor for MBB.
326 const MachineBasicBlock*
327 MinInstrCountEnsemble::pickTracePred(const MachineBasicBlock *MBB) {
328 if (MBB->pred_empty())
330 const MachineLoop *CurLoop = getLoopFor(MBB);
331 // Don't leave loops, and never follow back-edges.
332 if (CurLoop && MBB == CurLoop->getHeader())
334 unsigned CurCount = MTM.getResources(MBB)->InstrCount;
335 const MachineBasicBlock *Best = nullptr;
336 unsigned BestDepth = 0;
337 for (const MachineBasicBlock *Pred : MBB->predecessors()) {
338 const MachineTraceMetrics::TraceBlockInfo *PredTBI =
339 getDepthResources(Pred);
340 // Ignore cycles that aren't natural loops.
343 // Pick the predecessor that would give this block the smallest InstrDepth.
344 unsigned Depth = PredTBI->InstrDepth + CurCount;
345 if (!Best || Depth < BestDepth) {
353 // Select the preferred successor for MBB.
354 const MachineBasicBlock*
355 MinInstrCountEnsemble::pickTraceSucc(const MachineBasicBlock *MBB) {
356 if (MBB->pred_empty())
358 const MachineLoop *CurLoop = getLoopFor(MBB);
359 const MachineBasicBlock *Best = nullptr;
360 unsigned BestHeight = 0;
361 for (const MachineBasicBlock *Succ : MBB->successors()) {
362 // Don't consider back-edges.
363 if (CurLoop && Succ == CurLoop->getHeader())
365 // Don't consider successors exiting CurLoop.
366 if (isExitingLoop(CurLoop, getLoopFor(Succ)))
368 const MachineTraceMetrics::TraceBlockInfo *SuccTBI =
369 getHeightResources(Succ);
370 // Ignore cycles that aren't natural loops.
373 // Pick the successor that would give this block the smallest InstrHeight.
374 unsigned Height = SuccTBI->InstrHeight;
375 if (!Best || Height < BestHeight) {
383 // Get an Ensemble sub-class for the requested trace strategy.
384 MachineTraceMetrics::Ensemble *
385 MachineTraceMetrics::getEnsemble(MachineTraceMetrics::Strategy strategy) {
386 assert(strategy < TS_NumStrategies && "Invalid trace strategy enum");
387 Ensemble *&E = Ensembles[strategy];
391 // Allocate new Ensemble on demand.
393 case TS_MinInstrCount: return (E = new MinInstrCountEnsemble(this));
394 default: llvm_unreachable("Invalid trace strategy enum");
398 void MachineTraceMetrics::invalidate(const MachineBasicBlock *MBB) {
399 LLVM_DEBUG(dbgs() << "Invalidate traces through " << printMBBReference(*MBB)
401 BlockInfo[MBB->getNumber()].invalidate();
402 for (unsigned i = 0; i != TS_NumStrategies; ++i)
404 Ensembles[i]->invalidate(MBB);
407 void MachineTraceMetrics::verifyAnalysis() const {
411 assert(BlockInfo.size() == MF->getNumBlockIDs() && "Outdated BlockInfo size");
412 for (unsigned i = 0; i != TS_NumStrategies; ++i)
414 Ensembles[i]->verify();
418 //===----------------------------------------------------------------------===//
420 //===----------------------------------------------------------------------===//
422 // Traces are built by two CFG traversals. To avoid recomputing too much, use a
423 // set abstraction that confines the search to the current loop, and doesn't
429 MutableArrayRef<MachineTraceMetrics::TraceBlockInfo> Blocks;
430 SmallPtrSet<const MachineBasicBlock*, 8> Visited;
431 const MachineLoopInfo *Loops;
432 bool Downward = false;
434 LoopBounds(MutableArrayRef<MachineTraceMetrics::TraceBlockInfo> blocks,
435 const MachineLoopInfo *loops) : Blocks(blocks), Loops(loops) {}
438 } // end anonymous namespace
440 // Specialize po_iterator_storage in order to prune the post-order traversal so
441 // it is limited to the current loop and doesn't traverse the loop back edges.
445 class po_iterator_storage<LoopBounds, true> {
449 po_iterator_storage(LoopBounds &lb) : LB(lb) {}
451 void finishPostorder(const MachineBasicBlock*) {}
453 bool insertEdge(Optional<const MachineBasicBlock *> From,
454 const MachineBasicBlock *To) {
455 // Skip already visited To blocks.
456 MachineTraceMetrics::TraceBlockInfo &TBI = LB.Blocks[To->getNumber()];
457 if (LB.Downward ? TBI.hasValidHeight() : TBI.hasValidDepth())
459 // From is null once when To is the trace center block.
461 if (const MachineLoop *FromLoop = LB.Loops->getLoopFor(*From)) {
462 // Don't follow backedges, don't leave FromLoop when going upwards.
463 if ((LB.Downward ? To : *From) == FromLoop->getHeader())
465 // Don't leave FromLoop.
466 if (isExitingLoop(FromLoop, LB.Loops->getLoopFor(To)))
470 // To is a new block. Mark the block as visited in case the CFG has cycles
471 // that MachineLoopInfo didn't recognize as a natural loop.
472 return LB.Visited.insert(To).second;
476 } // end namespace llvm
478 /// Compute the trace through MBB.
479 void MachineTraceMetrics::Ensemble::computeTrace(const MachineBasicBlock *MBB) {
480 LLVM_DEBUG(dbgs() << "Computing " << getName() << " trace through "
481 << printMBBReference(*MBB) << '\n');
482 // Set up loop bounds for the backwards post-order traversal.
483 LoopBounds Bounds(BlockInfo, MTM.Loops);
485 // Run an upwards post-order search for the trace start.
486 Bounds.Downward = false;
487 Bounds.Visited.clear();
488 for (auto I : inverse_post_order_ext(MBB, Bounds)) {
489 LLVM_DEBUG(dbgs() << " pred for " << printMBBReference(*I) << ": ");
490 TraceBlockInfo &TBI = BlockInfo[I->getNumber()];
491 // All the predecessors have been visited, pick the preferred one.
492 TBI.Pred = pickTracePred(I);
495 dbgs() << printMBBReference(*TBI.Pred) << '\n';
499 // The trace leading to I is now known, compute the depth resources.
500 computeDepthResources(I);
503 // Run a downwards post-order search for the trace end.
504 Bounds.Downward = true;
505 Bounds.Visited.clear();
506 for (auto I : post_order_ext(MBB, Bounds)) {
507 LLVM_DEBUG(dbgs() << " succ for " << printMBBReference(*I) << ": ");
508 TraceBlockInfo &TBI = BlockInfo[I->getNumber()];
509 // All the successors have been visited, pick the preferred one.
510 TBI.Succ = pickTraceSucc(I);
513 dbgs() << printMBBReference(*TBI.Succ) << '\n';
517 // The trace leaving I is now known, compute the height resources.
518 computeHeightResources(I);
522 /// Invalidate traces through BadMBB.
524 MachineTraceMetrics::Ensemble::invalidate(const MachineBasicBlock *BadMBB) {
525 SmallVector<const MachineBasicBlock*, 16> WorkList;
526 TraceBlockInfo &BadTBI = BlockInfo[BadMBB->getNumber()];
528 // Invalidate height resources of blocks above MBB.
529 if (BadTBI.hasValidHeight()) {
530 BadTBI.invalidateHeight();
531 WorkList.push_back(BadMBB);
533 const MachineBasicBlock *MBB = WorkList.pop_back_val();
534 LLVM_DEBUG(dbgs() << "Invalidate " << printMBBReference(*MBB) << ' '
535 << getName() << " height.\n");
536 // Find any MBB predecessors that have MBB as their preferred successor.
537 // They are the only ones that need to be invalidated.
538 for (const MachineBasicBlock *Pred : MBB->predecessors()) {
539 TraceBlockInfo &TBI = BlockInfo[Pred->getNumber()];
540 if (!TBI.hasValidHeight())
542 if (TBI.Succ == MBB) {
543 TBI.invalidateHeight();
544 WorkList.push_back(Pred);
547 // Verify that TBI.Succ is actually a *I successor.
548 assert((!TBI.Succ || Pred->isSuccessor(TBI.Succ)) && "CFG changed");
550 } while (!WorkList.empty());
553 // Invalidate depth resources of blocks below MBB.
554 if (BadTBI.hasValidDepth()) {
555 BadTBI.invalidateDepth();
556 WorkList.push_back(BadMBB);
558 const MachineBasicBlock *MBB = WorkList.pop_back_val();
559 LLVM_DEBUG(dbgs() << "Invalidate " << printMBBReference(*MBB) << ' '
560 << getName() << " depth.\n");
561 // Find any MBB successors that have MBB as their preferred predecessor.
562 // They are the only ones that need to be invalidated.
563 for (const MachineBasicBlock *Succ : MBB->successors()) {
564 TraceBlockInfo &TBI = BlockInfo[Succ->getNumber()];
565 if (!TBI.hasValidDepth())
567 if (TBI.Pred == MBB) {
568 TBI.invalidateDepth();
569 WorkList.push_back(Succ);
572 // Verify that TBI.Pred is actually a *I predecessor.
573 assert((!TBI.Pred || Succ->isPredecessor(TBI.Pred)) && "CFG changed");
575 } while (!WorkList.empty());
578 // Clear any per-instruction data. We only have to do this for BadMBB itself
579 // because the instructions in that block may change. Other blocks may be
580 // invalidated, but their instructions will stay the same, so there is no
581 // need to erase the Cycle entries. They will be overwritten when we
583 for (const auto &I : *BadMBB)
587 void MachineTraceMetrics::Ensemble::verify() const {
589 assert(BlockInfo.size() == MTM.MF->getNumBlockIDs() &&
590 "Outdated BlockInfo size");
591 for (unsigned Num = 0, e = BlockInfo.size(); Num != e; ++Num) {
592 const TraceBlockInfo &TBI = BlockInfo[Num];
593 if (TBI.hasValidDepth() && TBI.Pred) {
594 const MachineBasicBlock *MBB = MTM.MF->getBlockNumbered(Num);
595 assert(MBB->isPredecessor(TBI.Pred) && "CFG doesn't match trace");
596 assert(BlockInfo[TBI.Pred->getNumber()].hasValidDepth() &&
597 "Trace is broken, depth should have been invalidated.");
598 const MachineLoop *Loop = getLoopFor(MBB);
599 assert(!(Loop && MBB == Loop->getHeader()) && "Trace contains backedge");
601 if (TBI.hasValidHeight() && TBI.Succ) {
602 const MachineBasicBlock *MBB = MTM.MF->getBlockNumbered(Num);
603 assert(MBB->isSuccessor(TBI.Succ) && "CFG doesn't match trace");
604 assert(BlockInfo[TBI.Succ->getNumber()].hasValidHeight() &&
605 "Trace is broken, height should have been invalidated.");
606 const MachineLoop *Loop = getLoopFor(MBB);
607 const MachineLoop *SuccLoop = getLoopFor(TBI.Succ);
608 assert(!(Loop && Loop == SuccLoop && TBI.Succ == Loop->getHeader()) &&
609 "Trace contains backedge");
615 //===----------------------------------------------------------------------===//
617 //===----------------------------------------------------------------------===//
619 // Compute the depth and height of each instruction based on data dependencies
620 // and instruction latencies. These cycle numbers assume that the CPU can issue
621 // an infinite number of instructions per cycle as long as their dependencies
624 // A data dependency is represented as a defining MI and operand numbers on the
625 // defining and using MI.
629 const MachineInstr *DefMI;
633 DataDep(const MachineInstr *DefMI, unsigned DefOp, unsigned UseOp)
634 : DefMI(DefMI), DefOp(DefOp), UseOp(UseOp) {}
636 /// Create a DataDep from an SSA form virtual register.
637 DataDep(const MachineRegisterInfo *MRI, unsigned VirtReg, unsigned UseOp)
639 assert(TargetRegisterInfo::isVirtualRegister(VirtReg));
640 MachineRegisterInfo::def_iterator DefI = MRI->def_begin(VirtReg);
641 assert(!DefI.atEnd() && "Register has no defs");
642 DefMI = DefI->getParent();
643 DefOp = DefI.getOperandNo();
644 assert((++DefI).atEnd() && "Register has multiple defs");
648 } // end anonymous namespace
650 // Get the input data dependencies that must be ready before UseMI can issue.
651 // Return true if UseMI has any physreg operands.
652 static bool getDataDeps(const MachineInstr &UseMI,
653 SmallVectorImpl<DataDep> &Deps,
654 const MachineRegisterInfo *MRI) {
655 // Debug values should not be included in any calculations.
656 if (UseMI.isDebugInstr())
659 bool HasPhysRegs = false;
660 for (MachineInstr::const_mop_iterator I = UseMI.operands_begin(),
661 E = UseMI.operands_end(); I != E; ++I) {
662 const MachineOperand &MO = *I;
665 unsigned Reg = MO.getReg();
668 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
672 // Collect virtual register reads.
674 Deps.push_back(DataDep(MRI, Reg, UseMI.getOperandNo(I)));
679 // Get the input data dependencies of a PHI instruction, using Pred as the
680 // preferred predecessor.
681 // This will add at most one dependency to Deps.
682 static void getPHIDeps(const MachineInstr &UseMI,
683 SmallVectorImpl<DataDep> &Deps,
684 const MachineBasicBlock *Pred,
685 const MachineRegisterInfo *MRI) {
686 // No predecessor at the beginning of a trace. Ignore dependencies.
689 assert(UseMI.isPHI() && UseMI.getNumOperands() % 2 && "Bad PHI");
690 for (unsigned i = 1; i != UseMI.getNumOperands(); i += 2) {
691 if (UseMI.getOperand(i + 1).getMBB() == Pred) {
692 unsigned Reg = UseMI.getOperand(i).getReg();
693 Deps.push_back(DataDep(MRI, Reg, i));
699 // Identify physreg dependencies for UseMI, and update the live regunit
700 // tracking set when scanning instructions downwards.
701 static void updatePhysDepsDownwards(const MachineInstr *UseMI,
702 SmallVectorImpl<DataDep> &Deps,
703 SparseSet<LiveRegUnit> &RegUnits,
704 const TargetRegisterInfo *TRI) {
705 SmallVector<unsigned, 8> Kills;
706 SmallVector<unsigned, 8> LiveDefOps;
708 for (MachineInstr::const_mop_iterator MI = UseMI->operands_begin(),
709 ME = UseMI->operands_end(); MI != ME; ++MI) {
710 const MachineOperand &MO = *MI;
713 unsigned Reg = MO.getReg();
714 if (!TargetRegisterInfo::isPhysicalRegister(Reg))
716 // Track live defs and kills for updating RegUnits.
719 Kills.push_back(Reg);
721 LiveDefOps.push_back(UseMI->getOperandNo(MI));
722 } else if (MO.isKill())
723 Kills.push_back(Reg);
724 // Identify dependencies.
727 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
728 SparseSet<LiveRegUnit>::iterator I = RegUnits.find(*Units);
729 if (I == RegUnits.end())
731 Deps.push_back(DataDep(I->MI, I->Op, UseMI->getOperandNo(MI)));
736 // Update RegUnits to reflect live registers after UseMI.
738 for (unsigned Kill : Kills)
739 for (MCRegUnitIterator Units(Kill, TRI); Units.isValid(); ++Units)
740 RegUnits.erase(*Units);
742 // Second, live defs.
743 for (unsigned DefOp : LiveDefOps) {
744 for (MCRegUnitIterator Units(UseMI->getOperand(DefOp).getReg(), TRI);
745 Units.isValid(); ++Units) {
746 LiveRegUnit &LRU = RegUnits[*Units];
753 /// The length of the critical path through a trace is the maximum of two path
756 /// 1. The maximum height+depth over all instructions in the trace center block.
758 /// 2. The longest cross-block dependency chain. For small blocks, it is
759 /// possible that the critical path through the trace doesn't include any
760 /// instructions in the block.
762 /// This function computes the second number from the live-in list of the
764 unsigned MachineTraceMetrics::Ensemble::
765 computeCrossBlockCriticalPath(const TraceBlockInfo &TBI) {
766 assert(TBI.HasValidInstrDepths && "Missing depth info");
767 assert(TBI.HasValidInstrHeights && "Missing height info");
769 for (const LiveInReg &LIR : TBI.LiveIns) {
770 if (!TargetRegisterInfo::isVirtualRegister(LIR.Reg))
772 const MachineInstr *DefMI = MTM.MRI->getVRegDef(LIR.Reg);
773 // Ignore dependencies outside the current trace.
774 const TraceBlockInfo &DefTBI = BlockInfo[DefMI->getParent()->getNumber()];
775 if (!DefTBI.isUsefulDominator(TBI))
777 unsigned Len = LIR.Height + Cycles[DefMI].Depth;
778 MaxLen = std::max(MaxLen, Len);
783 void MachineTraceMetrics::Ensemble::
784 updateDepth(MachineTraceMetrics::TraceBlockInfo &TBI, const MachineInstr &UseMI,
785 SparseSet<LiveRegUnit> &RegUnits) {
786 SmallVector<DataDep, 8> Deps;
787 // Collect all data dependencies.
789 getPHIDeps(UseMI, Deps, TBI.Pred, MTM.MRI);
790 else if (getDataDeps(UseMI, Deps, MTM.MRI))
791 updatePhysDepsDownwards(&UseMI, Deps, RegUnits, MTM.TRI);
793 // Filter and process dependencies, computing the earliest issue cycle.
795 for (const DataDep &Dep : Deps) {
796 const TraceBlockInfo&DepTBI =
797 BlockInfo[Dep.DefMI->getParent()->getNumber()];
798 // Ignore dependencies from outside the current trace.
799 if (!DepTBI.isUsefulDominator(TBI))
801 assert(DepTBI.HasValidInstrDepths && "Inconsistent dependency");
802 unsigned DepCycle = Cycles.lookup(Dep.DefMI).Depth;
803 // Add latency if DefMI is a real instruction. Transients get latency 0.
804 if (!Dep.DefMI->isTransient())
805 DepCycle += MTM.SchedModel
806 .computeOperandLatency(Dep.DefMI, Dep.DefOp, &UseMI, Dep.UseOp);
807 Cycle = std::max(Cycle, DepCycle);
809 // Remember the instruction depth.
810 InstrCycles &MICycles = Cycles[&UseMI];
811 MICycles.Depth = Cycle;
813 if (TBI.HasValidInstrHeights) {
814 // Update critical path length.
815 TBI.CriticalPath = std::max(TBI.CriticalPath, Cycle + MICycles.Height);
816 LLVM_DEBUG(dbgs() << TBI.CriticalPath << '\t' << Cycle << '\t' << UseMI);
818 LLVM_DEBUG(dbgs() << Cycle << '\t' << UseMI);
822 void MachineTraceMetrics::Ensemble::
823 updateDepth(const MachineBasicBlock *MBB, const MachineInstr &UseMI,
824 SparseSet<LiveRegUnit> &RegUnits) {
825 updateDepth(BlockInfo[MBB->getNumber()], UseMI, RegUnits);
828 void MachineTraceMetrics::Ensemble::
829 updateDepths(MachineBasicBlock::iterator Start,
830 MachineBasicBlock::iterator End,
831 SparseSet<LiveRegUnit> &RegUnits) {
832 for (; Start != End; Start++)
833 updateDepth(Start->getParent(), *Start, RegUnits);
836 /// Compute instruction depths for all instructions above or in MBB in its
837 /// trace. This assumes that the trace through MBB has already been computed.
838 void MachineTraceMetrics::Ensemble::
839 computeInstrDepths(const MachineBasicBlock *MBB) {
840 // The top of the trace may already be computed, and HasValidInstrDepths
841 // implies Head->HasValidInstrDepths, so we only need to start from the first
842 // block in the trace that needs to be recomputed.
843 SmallVector<const MachineBasicBlock*, 8> Stack;
845 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
846 assert(TBI.hasValidDepth() && "Incomplete trace");
847 if (TBI.HasValidInstrDepths)
849 Stack.push_back(MBB);
853 // FIXME: If MBB is non-null at this point, it is the last pre-computed block
854 // in the trace. We should track any live-out physregs that were defined in
855 // the trace. This is quite rare in SSA form, typically created by CSE
856 // hoisting a compare.
857 SparseSet<LiveRegUnit> RegUnits;
858 RegUnits.setUniverse(MTM.TRI->getNumRegUnits());
860 // Go through trace blocks in top-down order, stopping after the center block.
861 while (!Stack.empty()) {
862 MBB = Stack.pop_back_val();
863 LLVM_DEBUG(dbgs() << "\nDepths for " << printMBBReference(*MBB) << ":\n");
864 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
865 TBI.HasValidInstrDepths = true;
866 TBI.CriticalPath = 0;
868 // Print out resource depths here as well.
870 dbgs() << format("%7u Instructions\n", TBI.InstrDepth);
871 ArrayRef<unsigned> PRDepths = getProcResourceDepths(MBB->getNumber());
872 for (unsigned K = 0; K != PRDepths.size(); ++K)
874 unsigned Factor = MTM.SchedModel.getResourceFactor(K);
875 dbgs() << format("%6uc @ ", MTM.getCycles(PRDepths[K]))
876 << MTM.SchedModel.getProcResource(K)->Name << " ("
877 << PRDepths[K]/Factor << " ops x" << Factor << ")\n";
881 // Also compute the critical path length through MBB when possible.
882 if (TBI.HasValidInstrHeights)
883 TBI.CriticalPath = computeCrossBlockCriticalPath(TBI);
885 for (const auto &UseMI : *MBB) {
886 updateDepth(TBI, UseMI, RegUnits);
891 // Identify physreg dependencies for MI when scanning instructions upwards.
892 // Return the issue height of MI after considering any live regunits.
893 // Height is the issue height computed from virtual register dependencies alone.
894 static unsigned updatePhysDepsUpwards(const MachineInstr &MI, unsigned Height,
895 SparseSet<LiveRegUnit> &RegUnits,
896 const TargetSchedModel &SchedModel,
897 const TargetInstrInfo *TII,
898 const TargetRegisterInfo *TRI) {
899 SmallVector<unsigned, 8> ReadOps;
901 for (MachineInstr::const_mop_iterator MOI = MI.operands_begin(),
902 MOE = MI.operands_end();
904 const MachineOperand &MO = *MOI;
907 unsigned Reg = MO.getReg();
908 if (!TargetRegisterInfo::isPhysicalRegister(Reg))
911 ReadOps.push_back(MI.getOperandNo(MOI));
914 // This is a def of Reg. Remove corresponding entries from RegUnits, and
915 // update MI Height to consider the physreg dependencies.
916 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
917 SparseSet<LiveRegUnit>::iterator I = RegUnits.find(*Units);
918 if (I == RegUnits.end())
920 unsigned DepHeight = I->Cycle;
921 if (!MI.isTransient()) {
922 // We may not know the UseMI of this dependency, if it came from the
923 // live-in list. SchedModel can handle a NULL UseMI.
924 DepHeight += SchedModel.computeOperandLatency(&MI, MI.getOperandNo(MOI),
927 Height = std::max(Height, DepHeight);
928 // This regunit is dead above MI.
933 // Now we know the height of MI. Update any regunits read.
934 for (unsigned i = 0, e = ReadOps.size(); i != e; ++i) {
935 unsigned Reg = MI.getOperand(ReadOps[i]).getReg();
936 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
937 LiveRegUnit &LRU = RegUnits[*Units];
938 // Set the height to the highest reader of the unit.
939 if (LRU.Cycle <= Height && LRU.MI != &MI) {
950 using MIHeightMap = DenseMap<const MachineInstr *, unsigned>;
952 // Push the height of DefMI upwards if required to match UseMI.
953 // Return true if this is the first time DefMI was seen.
954 static bool pushDepHeight(const DataDep &Dep, const MachineInstr &UseMI,
955 unsigned UseHeight, MIHeightMap &Heights,
956 const TargetSchedModel &SchedModel,
957 const TargetInstrInfo *TII) {
958 // Adjust height by Dep.DefMI latency.
959 if (!Dep.DefMI->isTransient())
960 UseHeight += SchedModel.computeOperandLatency(Dep.DefMI, Dep.DefOp, &UseMI,
963 // Update Heights[DefMI] to be the maximum height seen.
964 MIHeightMap::iterator I;
966 std::tie(I, New) = Heights.insert(std::make_pair(Dep.DefMI, UseHeight));
970 // DefMI has been pushed before. Give it the max height.
971 if (I->second < UseHeight)
972 I->second = UseHeight;
976 /// Assuming that the virtual register defined by DefMI:DefOp was used by
977 /// Trace.back(), add it to the live-in lists of all the blocks in Trace. Stop
978 /// when reaching the block that contains DefMI.
979 void MachineTraceMetrics::Ensemble::
980 addLiveIns(const MachineInstr *DefMI, unsigned DefOp,
981 ArrayRef<const MachineBasicBlock*> Trace) {
982 assert(!Trace.empty() && "Trace should contain at least one block");
983 unsigned Reg = DefMI->getOperand(DefOp).getReg();
984 assert(TargetRegisterInfo::isVirtualRegister(Reg));
985 const MachineBasicBlock *DefMBB = DefMI->getParent();
987 // Reg is live-in to all blocks in Trace that follow DefMBB.
988 for (unsigned i = Trace.size(); i; --i) {
989 const MachineBasicBlock *MBB = Trace[i-1];
992 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
993 // Just add the register. The height will be updated later.
994 TBI.LiveIns.push_back(Reg);
998 /// Compute instruction heights in the trace through MBB. This updates MBB and
999 /// the blocks below it in the trace. It is assumed that the trace has already
1001 void MachineTraceMetrics::Ensemble::
1002 computeInstrHeights(const MachineBasicBlock *MBB) {
1003 // The bottom of the trace may already be computed.
1004 // Find the blocks that need updating.
1005 SmallVector<const MachineBasicBlock*, 8> Stack;
1007 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
1008 assert(TBI.hasValidHeight() && "Incomplete trace");
1009 if (TBI.HasValidInstrHeights)
1011 Stack.push_back(MBB);
1012 TBI.LiveIns.clear();
1016 // As we move upwards in the trace, keep track of instructions that are
1017 // required by deeper trace instructions. Map MI -> height required so far.
1018 MIHeightMap Heights;
1020 // For physregs, the def isn't known when we see the use.
1021 // Instead, keep track of the highest use of each regunit.
1022 SparseSet<LiveRegUnit> RegUnits;
1023 RegUnits.setUniverse(MTM.TRI->getNumRegUnits());
1025 // If the bottom of the trace was already precomputed, initialize heights
1026 // from its live-in list.
1027 // MBB is the highest precomputed block in the trace.
1029 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
1030 for (LiveInReg &LI : TBI.LiveIns) {
1031 if (TargetRegisterInfo::isVirtualRegister(LI.Reg)) {
1032 // For virtual registers, the def latency is included.
1033 unsigned &Height = Heights[MTM.MRI->getVRegDef(LI.Reg)];
1034 if (Height < LI.Height)
1037 // For register units, the def latency is not included because we don't
1038 // know the def yet.
1039 RegUnits[LI.Reg].Cycle = LI.Height;
1044 // Go through the trace blocks in bottom-up order.
1045 SmallVector<DataDep, 8> Deps;
1046 for (;!Stack.empty(); Stack.pop_back()) {
1048 LLVM_DEBUG(dbgs() << "Heights for " << printMBBReference(*MBB) << ":\n");
1049 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
1050 TBI.HasValidInstrHeights = true;
1051 TBI.CriticalPath = 0;
1054 dbgs() << format("%7u Instructions\n", TBI.InstrHeight);
1055 ArrayRef<unsigned> PRHeights = getProcResourceHeights(MBB->getNumber());
1056 for (unsigned K = 0; K != PRHeights.size(); ++K)
1058 unsigned Factor = MTM.SchedModel.getResourceFactor(K);
1059 dbgs() << format("%6uc @ ", MTM.getCycles(PRHeights[K]))
1060 << MTM.SchedModel.getProcResource(K)->Name << " ("
1061 << PRHeights[K]/Factor << " ops x" << Factor << ")\n";
1065 // Get dependencies from PHIs in the trace successor.
1066 const MachineBasicBlock *Succ = TBI.Succ;
1067 // If MBB is the last block in the trace, and it has a back-edge to the
1068 // loop header, get loop-carried dependencies from PHIs in the header. For
1069 // that purpose, pretend that all the loop header PHIs have height 0.
1071 if (const MachineLoop *Loop = getLoopFor(MBB))
1072 if (MBB->isSuccessor(Loop->getHeader()))
1073 Succ = Loop->getHeader();
1076 for (const auto &PHI : *Succ) {
1080 getPHIDeps(PHI, Deps, MBB, MTM.MRI);
1081 if (!Deps.empty()) {
1082 // Loop header PHI heights are all 0.
1083 unsigned Height = TBI.Succ ? Cycles.lookup(&PHI).Height : 0;
1084 LLVM_DEBUG(dbgs() << "pred\t" << Height << '\t' << PHI);
1085 if (pushDepHeight(Deps.front(), PHI, Height, Heights, MTM.SchedModel,
1087 addLiveIns(Deps.front().DefMI, Deps.front().DefOp, Stack);
1092 // Go through the block backwards.
1093 for (MachineBasicBlock::const_iterator BI = MBB->end(), BB = MBB->begin();
1095 const MachineInstr &MI = *--BI;
1097 // Find the MI height as determined by virtual register uses in the
1100 MIHeightMap::iterator HeightI = Heights.find(&MI);
1101 if (HeightI != Heights.end()) {
1102 Cycle = HeightI->second;
1103 // We won't be seeing any more MI uses.
1104 Heights.erase(HeightI);
1107 // Don't process PHI deps. They depend on the specific predecessor, and
1108 // we'll get them when visiting the predecessor.
1110 bool HasPhysRegs = !MI.isPHI() && getDataDeps(MI, Deps, MTM.MRI);
1112 // There may also be regunit dependencies to include in the height.
1114 Cycle = updatePhysDepsUpwards(MI, Cycle, RegUnits, MTM.SchedModel,
1117 // Update the required height of any virtual registers read by MI.
1118 for (const DataDep &Dep : Deps)
1119 if (pushDepHeight(Dep, MI, Cycle, Heights, MTM.SchedModel, MTM.TII))
1120 addLiveIns(Dep.DefMI, Dep.DefOp, Stack);
1122 InstrCycles &MICycles = Cycles[&MI];
1123 MICycles.Height = Cycle;
1124 if (!TBI.HasValidInstrDepths) {
1125 LLVM_DEBUG(dbgs() << Cycle << '\t' << MI);
1128 // Update critical path length.
1129 TBI.CriticalPath = std::max(TBI.CriticalPath, Cycle + MICycles.Depth);
1130 LLVM_DEBUG(dbgs() << TBI.CriticalPath << '\t' << Cycle << '\t' << MI);
1133 // Update virtual live-in heights. They were added by addLiveIns() with a 0
1134 // height because the final height isn't known until now.
1135 LLVM_DEBUG(dbgs() << printMBBReference(*MBB) << " Live-ins:");
1136 for (LiveInReg &LIR : TBI.LiveIns) {
1137 const MachineInstr *DefMI = MTM.MRI->getVRegDef(LIR.Reg);
1138 LIR.Height = Heights.lookup(DefMI);
1139 LLVM_DEBUG(dbgs() << ' ' << printReg(LIR.Reg) << '@' << LIR.Height);
1142 // Transfer the live regunits to the live-in list.
1143 for (SparseSet<LiveRegUnit>::const_iterator
1144 RI = RegUnits.begin(), RE = RegUnits.end(); RI != RE; ++RI) {
1145 TBI.LiveIns.push_back(LiveInReg(RI->RegUnit, RI->Cycle));
1146 LLVM_DEBUG(dbgs() << ' ' << printRegUnit(RI->RegUnit, MTM.TRI) << '@'
1149 LLVM_DEBUG(dbgs() << '\n');
1151 if (!TBI.HasValidInstrDepths)
1153 // Add live-ins to the critical path length.
1154 TBI.CriticalPath = std::max(TBI.CriticalPath,
1155 computeCrossBlockCriticalPath(TBI));
1156 LLVM_DEBUG(dbgs() << "Critical path: " << TBI.CriticalPath << '\n');
1160 MachineTraceMetrics::Trace
1161 MachineTraceMetrics::Ensemble::getTrace(const MachineBasicBlock *MBB) {
1162 TraceBlockInfo &TBI = BlockInfo[MBB->getNumber()];
1164 if (!TBI.hasValidDepth() || !TBI.hasValidHeight())
1166 if (!TBI.HasValidInstrDepths)
1167 computeInstrDepths(MBB);
1168 if (!TBI.HasValidInstrHeights)
1169 computeInstrHeights(MBB);
1171 return Trace(*this, TBI);
1175 MachineTraceMetrics::Trace::getInstrSlack(const MachineInstr &MI) const {
1176 assert(getBlockNum() == unsigned(MI.getParent()->getNumber()) &&
1177 "MI must be in the trace center block");
1178 InstrCycles Cyc = getInstrCycles(MI);
1179 return getCriticalPath() - (Cyc.Depth + Cyc.Height);
1183 MachineTraceMetrics::Trace::getPHIDepth(const MachineInstr &PHI) const {
1184 const MachineBasicBlock *MBB = TE.MTM.MF->getBlockNumbered(getBlockNum());
1185 SmallVector<DataDep, 1> Deps;
1186 getPHIDeps(PHI, Deps, MBB, TE.MTM.MRI);
1187 assert(Deps.size() == 1 && "PHI doesn't have MBB as a predecessor");
1188 DataDep &Dep = Deps.front();
1189 unsigned DepCycle = getInstrCycles(*Dep.DefMI).Depth;
1190 // Add latency if DefMI is a real instruction. Transients get latency 0.
1191 if (!Dep.DefMI->isTransient())
1192 DepCycle += TE.MTM.SchedModel.computeOperandLatency(Dep.DefMI, Dep.DefOp,
1197 /// When bottom is set include instructions in current block in estimate.
1198 unsigned MachineTraceMetrics::Trace::getResourceDepth(bool Bottom) const {
1199 // Find the limiting processor resource.
1200 // Numbers have been pre-scaled to be comparable.
1202 ArrayRef<unsigned> PRDepths = TE.getProcResourceDepths(getBlockNum());
1204 ArrayRef<unsigned> PRCycles = TE.MTM.getProcResourceCycles(getBlockNum());
1205 for (unsigned K = 0; K != PRDepths.size(); ++K)
1206 PRMax = std::max(PRMax, PRDepths[K] + PRCycles[K]);
1208 for (unsigned K = 0; K != PRDepths.size(); ++K)
1209 PRMax = std::max(PRMax, PRDepths[K]);
1211 // Convert to cycle count.
1212 PRMax = TE.MTM.getCycles(PRMax);
1214 /// All instructions before current block
1215 unsigned Instrs = TBI.InstrDepth;
1216 // plus instructions in current block
1218 Instrs += TE.MTM.BlockInfo[getBlockNum()].InstrCount;
1219 if (unsigned IW = TE.MTM.SchedModel.getIssueWidth())
1221 // Assume issue width 1 without a schedule model.
1222 return std::max(Instrs, PRMax);
1225 unsigned MachineTraceMetrics::Trace::getResourceLength(
1226 ArrayRef<const MachineBasicBlock *> Extrablocks,
1227 ArrayRef<const MCSchedClassDesc *> ExtraInstrs,
1228 ArrayRef<const MCSchedClassDesc *> RemoveInstrs) const {
1229 // Add up resources above and below the center block.
1230 ArrayRef<unsigned> PRDepths = TE.getProcResourceDepths(getBlockNum());
1231 ArrayRef<unsigned> PRHeights = TE.getProcResourceHeights(getBlockNum());
1234 // Capture computing cycles from extra instructions
1235 auto extraCycles = [this](ArrayRef<const MCSchedClassDesc *> Instrs,
1236 unsigned ResourceIdx)
1238 unsigned Cycles = 0;
1239 for (const MCSchedClassDesc *SC : Instrs) {
1242 for (TargetSchedModel::ProcResIter
1243 PI = TE.MTM.SchedModel.getWriteProcResBegin(SC),
1244 PE = TE.MTM.SchedModel.getWriteProcResEnd(SC);
1246 if (PI->ProcResourceIdx != ResourceIdx)
1249 (PI->Cycles * TE.MTM.SchedModel.getResourceFactor(ResourceIdx));
1255 for (unsigned K = 0; K != PRDepths.size(); ++K) {
1256 unsigned PRCycles = PRDepths[K] + PRHeights[K];
1257 for (const MachineBasicBlock *MBB : Extrablocks)
1258 PRCycles += TE.MTM.getProcResourceCycles(MBB->getNumber())[K];
1259 PRCycles += extraCycles(ExtraInstrs, K);
1260 PRCycles -= extraCycles(RemoveInstrs, K);
1261 PRMax = std::max(PRMax, PRCycles);
1263 // Convert to cycle count.
1264 PRMax = TE.MTM.getCycles(PRMax);
1266 // Instrs: #instructions in current trace outside current block.
1267 unsigned Instrs = TBI.InstrDepth + TBI.InstrHeight;
1268 // Add instruction count from the extra blocks.
1269 for (const MachineBasicBlock *MBB : Extrablocks)
1270 Instrs += TE.MTM.getResources(MBB)->InstrCount;
1271 Instrs += ExtraInstrs.size();
1272 Instrs -= RemoveInstrs.size();
1273 if (unsigned IW = TE.MTM.SchedModel.getIssueWidth())
1275 // Assume issue width 1 without a schedule model.
1276 return std::max(Instrs, PRMax);
1279 bool MachineTraceMetrics::Trace::isDepInTrace(const MachineInstr &DefMI,
1280 const MachineInstr &UseMI) const {
1281 if (DefMI.getParent() == UseMI.getParent())
1284 const TraceBlockInfo &DepTBI = TE.BlockInfo[DefMI.getParent()->getNumber()];
1285 const TraceBlockInfo &TBI = TE.BlockInfo[UseMI.getParent()->getNumber()];
1287 return DepTBI.isUsefulDominator(TBI);
1290 void MachineTraceMetrics::Ensemble::print(raw_ostream &OS) const {
1291 OS << getName() << " ensemble:\n";
1292 for (unsigned i = 0, e = BlockInfo.size(); i != e; ++i) {
1293 OS << " %bb." << i << '\t';
1294 BlockInfo[i].print(OS);
1299 void MachineTraceMetrics::TraceBlockInfo::print(raw_ostream &OS) const {
1300 if (hasValidDepth()) {
1301 OS << "depth=" << InstrDepth;
1303 OS << " pred=" << printMBBReference(*Pred);
1306 OS << " head=%bb." << Head;
1307 if (HasValidInstrDepths)
1310 OS << "depth invalid";
1312 if (hasValidHeight()) {
1313 OS << "height=" << InstrHeight;
1315 OS << " succ=" << printMBBReference(*Succ);
1318 OS << " tail=%bb." << Tail;
1319 if (HasValidInstrHeights)
1322 OS << "height invalid";
1323 if (HasValidInstrDepths && HasValidInstrHeights)
1324 OS << ", crit=" << CriticalPath;
1327 void MachineTraceMetrics::Trace::print(raw_ostream &OS) const {
1328 unsigned MBBNum = &TBI - &TE.BlockInfo[0];
1330 OS << TE.getName() << " trace %bb." << TBI.Head << " --> %bb." << MBBNum
1331 << " --> %bb." << TBI.Tail << ':';
1332 if (TBI.hasValidHeight() && TBI.hasValidDepth())
1333 OS << ' ' << getInstrCount() << " instrs.";
1334 if (TBI.HasValidInstrDepths && TBI.HasValidInstrHeights)
1335 OS << ' ' << TBI.CriticalPath << " cycles.";
1337 const MachineTraceMetrics::TraceBlockInfo *Block = &TBI;
1338 OS << "\n%bb." << MBBNum;
1339 while (Block->hasValidDepth() && Block->Pred) {
1340 unsigned Num = Block->Pred->getNumber();
1341 OS << " <- " << printMBBReference(*Block->Pred);
1342 Block = &TE.BlockInfo[Num];
1347 while (Block->hasValidHeight() && Block->Succ) {
1348 unsigned Num = Block->Succ->getNumber();
1349 OS << " -> " << printMBBReference(*Block->Succ);
1350 Block = &TE.BlockInfo[Num];