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PGOInstrumentation.cpp
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1 //===- PGOInstrumentation.cpp - MST-based PGO Instrumentation -------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements PGO instrumentation using a minimum spanning tree based
11 // on the following paper:
12 // [1] Donald E. Knuth, Francis R. Stevenson. Optimal measurement of points
13 // for program frequency counts. BIT Numerical Mathematics 1973, Volume 13,
14 // Issue 3, pp 313-322
15 // The idea of the algorithm based on the fact that for each node (except for
16 // the entry and exit), the sum of incoming edge counts equals the sum of
17 // outgoing edge counts. The count of edge on spanning tree can be derived from
18 // those edges not on the spanning tree. Knuth proves this method instruments
19 // the minimum number of edges.
20 //
21 // The minimal spanning tree here is actually a maximum weight tree -- on-tree
22 // edges have higher frequencies (more likely to execute). The idea is to
23 // instrument those less frequently executed edges to reduce the runtime
24 // overhead of instrumented binaries.
25 //
26 // This file contains two passes:
27 // (1) Pass PGOInstrumentationGen which instruments the IR to generate edge
28 // count profile, and generates the instrumentation for indirect call
29 // profiling.
30 // (2) Pass PGOInstrumentationUse which reads the edge count profile and
31 // annotates the branch weights. It also reads the indirect call value
32 // profiling records and annotate the indirect call instructions.
33 //
34 // To get the precise counter information, These two passes need to invoke at
35 // the same compilation point (so they see the same IR). For pass
36 // PGOInstrumentationGen, the real work is done in instrumentOneFunc(). For
37 // pass PGOInstrumentationUse, the real work in done in class PGOUseFunc and
38 // the profile is opened in module level and passed to each PGOUseFunc instance.
39 // The shared code for PGOInstrumentationGen and PGOInstrumentationUse is put
40 // in class FuncPGOInstrumentation.
41 //
42 // Class PGOEdge represents a CFG edge and some auxiliary information. Class
43 // BBInfo contains auxiliary information for each BB. These two classes are used
44 // in pass PGOInstrumentationGen. Class PGOUseEdge and UseBBInfo are the derived
45 // class of PGOEdge and BBInfo, respectively. They contains extra data structure
46 // used in populating profile counters.
47 // The MST implementation is in Class CFGMST (CFGMST.h).
48 //
49 //===----------------------------------------------------------------------===//
50 
52 #include "CFGMST.h"
53 #include "llvm/ADT/APInt.h"
54 #include "llvm/ADT/ArrayRef.h"
55 #include "llvm/ADT/STLExtras.h"
56 #include "llvm/ADT/SmallVector.h"
57 #include "llvm/ADT/Statistic.h"
58 #include "llvm/ADT/StringRef.h"
59 #include "llvm/ADT/Triple.h"
60 #include "llvm/ADT/Twine.h"
61 #include "llvm/ADT/iterator.h"
65 #include "llvm/Analysis/CFG.h"
67 #include "llvm/Analysis/LoopInfo.h"
69 #include "llvm/IR/Attributes.h"
70 #include "llvm/IR/BasicBlock.h"
71 #include "llvm/IR/CFG.h"
72 #include "llvm/IR/CallSite.h"
73 #include "llvm/IR/Comdat.h"
74 #include "llvm/IR/Constant.h"
75 #include "llvm/IR/Constants.h"
76 #include "llvm/IR/DiagnosticInfo.h"
77 #include "llvm/IR/Dominators.h"
78 #include "llvm/IR/Function.h"
79 #include "llvm/IR/GlobalAlias.h"
80 #include "llvm/IR/GlobalValue.h"
81 #include "llvm/IR/GlobalVariable.h"
82 #include "llvm/IR/IRBuilder.h"
83 #include "llvm/IR/InstVisitor.h"
84 #include "llvm/IR/InstrTypes.h"
85 #include "llvm/IR/Instruction.h"
86 #include "llvm/IR/Instructions.h"
87 #include "llvm/IR/IntrinsicInst.h"
88 #include "llvm/IR/Intrinsics.h"
89 #include "llvm/IR/LLVMContext.h"
90 #include "llvm/IR/MDBuilder.h"
91 #include "llvm/IR/Module.h"
92 #include "llvm/IR/PassManager.h"
93 #include "llvm/IR/ProfileSummary.h"
94 #include "llvm/IR/Type.h"
95 #include "llvm/IR/Value.h"
96 #include "llvm/Pass.h"
100 #include "llvm/Support/Casting.h"
103 #include "llvm/Support/Debug.h"
104 #include "llvm/Support/Error.h"
107 #include "llvm/Support/JamCRC.h"
111 #include <algorithm>
112 #include <cassert>
113 #include <cstdint>
114 #include <memory>
115 #include <numeric>
116 #include <string>
117 #include <unordered_map>
118 #include <utility>
119 #include <vector>
120 
121 using namespace llvm;
123 
124 #define DEBUG_TYPE "pgo-instrumentation"
125 
126 STATISTIC(NumOfPGOInstrument, "Number of edges instrumented.");
127 STATISTIC(NumOfPGOSelectInsts, "Number of select instruction instrumented.");
128 STATISTIC(NumOfPGOMemIntrinsics, "Number of mem intrinsics instrumented.");
129 STATISTIC(NumOfPGOEdge, "Number of edges.");
130 STATISTIC(NumOfPGOBB, "Number of basic-blocks.");
131 STATISTIC(NumOfPGOSplit, "Number of critical edge splits.");
132 STATISTIC(NumOfPGOFunc, "Number of functions having valid profile counts.");
133 STATISTIC(NumOfPGOMismatch, "Number of functions having mismatch profile.");
134 STATISTIC(NumOfPGOMissing, "Number of functions without profile.");
135 STATISTIC(NumOfPGOICall, "Number of indirect call value instrumentations.");
136 
137 // Command line option to specify the file to read profile from. This is
138 // mainly used for testing.
140  PGOTestProfileFile("pgo-test-profile-file", cl::init(""), cl::Hidden,
141  cl::value_desc("filename"),
142  cl::desc("Specify the path of profile data file. This is"
143  "mainly for test purpose."));
144 
145 // Command line option to disable value profiling. The default is false:
146 // i.e. value profiling is enabled by default. This is for debug purpose.
147 static cl::opt<bool> DisableValueProfiling("disable-vp", cl::init(false),
148  cl::Hidden,
149  cl::desc("Disable Value Profiling"));
150 
151 // Command line option to set the maximum number of VP annotations to write to
152 // the metadata for a single indirect call callsite.
154  "icp-max-annotations", cl::init(3), cl::Hidden, cl::ZeroOrMore,
155  cl::desc("Max number of annotations for a single indirect "
156  "call callsite"));
157 
158 // Command line option to set the maximum number of value annotations
159 // to write to the metadata for a single memop intrinsic.
161  "memop-max-annotations", cl::init(4), cl::Hidden, cl::ZeroOrMore,
162  cl::desc("Max number of preicise value annotations for a single memop"
163  "intrinsic"));
164 
165 // Command line option to control appending FunctionHash to the name of a COMDAT
166 // function. This is to avoid the hash mismatch caused by the preinliner.
168  "do-comdat-renaming", cl::init(false), cl::Hidden,
169  cl::desc("Append function hash to the name of COMDAT function to avoid "
170  "function hash mismatch due to the preinliner"));
171 
172 // Command line option to enable/disable the warning about missing profile
173 // information.
174 static cl::opt<bool>
175  PGOWarnMissing("pgo-warn-missing-function", cl::init(false), cl::Hidden,
176  cl::desc("Use this option to turn on/off "
177  "warnings about missing profile data for "
178  "functions."));
179 
180 // Command line option to enable/disable the warning about a hash mismatch in
181 // the profile data.
182 static cl::opt<bool>
183  NoPGOWarnMismatch("no-pgo-warn-mismatch", cl::init(false), cl::Hidden,
184  cl::desc("Use this option to turn off/on "
185  "warnings about profile cfg mismatch."));
186 
187 // Command line option to enable/disable the warning about a hash mismatch in
188 // the profile data for Comdat functions, which often turns out to be false
189 // positive due to the pre-instrumentation inline.
190 static cl::opt<bool>
191  NoPGOWarnMismatchComdat("no-pgo-warn-mismatch-comdat", cl::init(true),
192  cl::Hidden,
193  cl::desc("The option is used to turn on/off "
194  "warnings about hash mismatch for comdat "
195  "functions."));
196 
197 // Command line option to enable/disable select instruction instrumentation.
198 static cl::opt<bool>
199  PGOInstrSelect("pgo-instr-select", cl::init(true), cl::Hidden,
200  cl::desc("Use this option to turn on/off SELECT "
201  "instruction instrumentation. "));
202 
203 // Command line option to turn on CFG dot or text dump of raw profile counts
205  "pgo-view-raw-counts", cl::Hidden,
206  cl::desc("A boolean option to show CFG dag or text "
207  "with raw profile counts from "
208  "profile data. See also option "
209  "-pgo-view-counts. To limit graph "
210  "display to only one function, use "
211  "filtering option -view-bfi-func-name."),
212  cl::values(clEnumValN(PGOVCT_None, "none", "do not show."),
213  clEnumValN(PGOVCT_Graph, "graph", "show a graph."),
214  clEnumValN(PGOVCT_Text, "text", "show in text.")));
215 
216 // Command line option to enable/disable memop intrinsic call.size profiling.
217 static cl::opt<bool>
218  PGOInstrMemOP("pgo-instr-memop", cl::init(true), cl::Hidden,
219  cl::desc("Use this option to turn on/off "
220  "memory intrinsic size profiling."));
221 
222 // Emit branch probability as optimization remarks.
223 static cl::opt<bool>
224  EmitBranchProbability("pgo-emit-branch-prob", cl::init(false), cl::Hidden,
225  cl::desc("When this option is on, the annotated "
226  "branch probability will be emitted as "
227  "optimization remarks: -{Rpass|"
228  "pass-remarks}=pgo-instrumentation"));
229 
230 // Command line option to turn on CFG dot dump after profile annotation.
231 // Defined in Analysis/BlockFrequencyInfo.cpp: -pgo-view-counts
233 
234 // Command line option to specify the name of the function for CFG dump
235 // Defined in Analysis/BlockFrequencyInfo.cpp: -view-bfi-func-name=
237 
238 // Return a string describing the branch condition that can be
239 // used in static branch probability heuristics:
240 static std::string getBranchCondString(Instruction *TI) {
241  BranchInst *BI = dyn_cast<BranchInst>(TI);
242  if (!BI || !BI->isConditional())
243  return std::string();
244 
245  Value *Cond = BI->getCondition();
246  ICmpInst *CI = dyn_cast<ICmpInst>(Cond);
247  if (!CI)
248  return std::string();
249 
250  std::string result;
251  raw_string_ostream OS(result);
252  OS << CmpInst::getPredicateName(CI->getPredicate()) << "_";
253  CI->getOperand(0)->getType()->print(OS, true);
254 
255  Value *RHS = CI->getOperand(1);
256  ConstantInt *CV = dyn_cast<ConstantInt>(RHS);
257  if (CV) {
258  if (CV->isZero())
259  OS << "_Zero";
260  else if (CV->isOne())
261  OS << "_One";
262  else if (CV->isMinusOne())
263  OS << "_MinusOne";
264  else
265  OS << "_Const";
266  }
267  OS.flush();
268  return result;
269 }
270 
271 namespace {
272 
273 /// The select instruction visitor plays three roles specified
274 /// by the mode. In \c VM_counting mode, it simply counts the number of
275 /// select instructions. In \c VM_instrument mode, it inserts code to count
276 /// the number times TrueValue of select is taken. In \c VM_annotate mode,
277 /// it reads the profile data and annotate the select instruction with metadata.
278 enum VisitMode { VM_counting, VM_instrument, VM_annotate };
279 class PGOUseFunc;
280 
281 /// Instruction Visitor class to visit select instructions.
282 struct SelectInstVisitor : public InstVisitor<SelectInstVisitor> {
283  Function &F;
284  unsigned NSIs = 0; // Number of select instructions instrumented.
285  VisitMode Mode = VM_counting; // Visiting mode.
286  unsigned *CurCtrIdx = nullptr; // Pointer to current counter index.
287  unsigned TotalNumCtrs = 0; // Total number of counters
288  GlobalVariable *FuncNameVar = nullptr;
289  uint64_t FuncHash = 0;
290  PGOUseFunc *UseFunc = nullptr;
291 
292  SelectInstVisitor(Function &Func) : F(Func) {}
293 
294  void countSelects(Function &Func) {
295  NSIs = 0;
296  Mode = VM_counting;
297  visit(Func);
298  }
299 
300  // Visit the IR stream and instrument all select instructions. \p
301  // Ind is a pointer to the counter index variable; \p TotalNC
302  // is the total number of counters; \p FNV is the pointer to the
303  // PGO function name var; \p FHash is the function hash.
304  void instrumentSelects(Function &Func, unsigned *Ind, unsigned TotalNC,
305  GlobalVariable *FNV, uint64_t FHash) {
306  Mode = VM_instrument;
307  CurCtrIdx = Ind;
308  TotalNumCtrs = TotalNC;
309  FuncHash = FHash;
310  FuncNameVar = FNV;
311  visit(Func);
312  }
313 
314  // Visit the IR stream and annotate all select instructions.
315  void annotateSelects(Function &Func, PGOUseFunc *UF, unsigned *Ind) {
316  Mode = VM_annotate;
317  UseFunc = UF;
318  CurCtrIdx = Ind;
319  visit(Func);
320  }
321 
322  void instrumentOneSelectInst(SelectInst &SI);
323  void annotateOneSelectInst(SelectInst &SI);
324 
325  // Visit \p SI instruction and perform tasks according to visit mode.
326  void visitSelectInst(SelectInst &SI);
327 
328  // Return the number of select instructions. This needs be called after
329  // countSelects().
330  unsigned getNumOfSelectInsts() const { return NSIs; }
331 };
332 
333 /// Instruction Visitor class to visit memory intrinsic calls.
334 struct MemIntrinsicVisitor : public InstVisitor<MemIntrinsicVisitor> {
335  Function &F;
336  unsigned NMemIs = 0; // Number of memIntrinsics instrumented.
337  VisitMode Mode = VM_counting; // Visiting mode.
338  unsigned CurCtrId = 0; // Current counter index.
339  unsigned TotalNumCtrs = 0; // Total number of counters
340  GlobalVariable *FuncNameVar = nullptr;
341  uint64_t FuncHash = 0;
342  PGOUseFunc *UseFunc = nullptr;
343  std::vector<Instruction *> Candidates;
344 
345  MemIntrinsicVisitor(Function &Func) : F(Func) {}
346 
347  void countMemIntrinsics(Function &Func) {
348  NMemIs = 0;
349  Mode = VM_counting;
350  visit(Func);
351  }
352 
353  void instrumentMemIntrinsics(Function &Func, unsigned TotalNC,
354  GlobalVariable *FNV, uint64_t FHash) {
355  Mode = VM_instrument;
356  TotalNumCtrs = TotalNC;
357  FuncHash = FHash;
358  FuncNameVar = FNV;
359  visit(Func);
360  }
361 
362  std::vector<Instruction *> findMemIntrinsics(Function &Func) {
363  Candidates.clear();
364  Mode = VM_annotate;
365  visit(Func);
366  return Candidates;
367  }
368 
369  // Visit the IR stream and annotate all mem intrinsic call instructions.
370  void instrumentOneMemIntrinsic(MemIntrinsic &MI);
371 
372  // Visit \p MI instruction and perform tasks according to visit mode.
373  void visitMemIntrinsic(MemIntrinsic &SI);
374 
375  unsigned getNumOfMemIntrinsics() const { return NMemIs; }
376 };
377 
378 class PGOInstrumentationGenLegacyPass : public ModulePass {
379 public:
380  static char ID;
381 
382  PGOInstrumentationGenLegacyPass() : ModulePass(ID) {
385  }
386 
387  StringRef getPassName() const override { return "PGOInstrumentationGenPass"; }
388 
389 private:
390  bool runOnModule(Module &M) override;
391 
392  void getAnalysisUsage(AnalysisUsage &AU) const override {
394  }
395 };
396 
397 class PGOInstrumentationUseLegacyPass : public ModulePass {
398 public:
399  static char ID;
400 
401  // Provide the profile filename as the parameter.
402  PGOInstrumentationUseLegacyPass(std::string Filename = "")
403  : ModulePass(ID), ProfileFileName(std::move(Filename)) {
404  if (!PGOTestProfileFile.empty())
405  ProfileFileName = PGOTestProfileFile;
408  }
409 
410  StringRef getPassName() const override { return "PGOInstrumentationUsePass"; }
411 
412 private:
413  std::string ProfileFileName;
414 
415  bool runOnModule(Module &M) override;
416 
417  void getAnalysisUsage(AnalysisUsage &AU) const override {
419  }
420 };
421 
422 } // end anonymous namespace
423 
425 
426 INITIALIZE_PASS_BEGIN(PGOInstrumentationGenLegacyPass, "pgo-instr-gen",
427  "PGO instrumentation.", false, false)
430 INITIALIZE_PASS_END(PGOInstrumentationGenLegacyPass, "pgo-instr-gen",
431  "PGO instrumentation.", false, false)
432 
434  return new PGOInstrumentationGenLegacyPass();
435 }
436 
438 
439 INITIALIZE_PASS_BEGIN(PGOInstrumentationUseLegacyPass, "pgo-instr-use",
440  "Read PGO instrumentation profile.", false, false)
443 INITIALIZE_PASS_END(PGOInstrumentationUseLegacyPass, "pgo-instr-use",
444  "Read PGO instrumentation profile.", false, false)
445 
447  return new PGOInstrumentationUseLegacyPass(Filename.str());
448 }
449 
450 namespace {
451 
452 /// An MST based instrumentation for PGO
453 ///
454 /// Implements a Minimum Spanning Tree (MST) based instrumentation for PGO
455 /// in the function level.
456 struct PGOEdge {
457  // This class implements the CFG edges. Note the CFG can be a multi-graph.
458  // So there might be multiple edges with same SrcBB and DestBB.
459  const BasicBlock *SrcBB;
460  const BasicBlock *DestBB;
461  uint64_t Weight;
462  bool InMST = false;
463  bool Removed = false;
464  bool IsCritical = false;
465 
466  PGOEdge(const BasicBlock *Src, const BasicBlock *Dest, uint64_t W = 1)
467  : SrcBB(Src), DestBB(Dest), Weight(W) {}
468 
469  // Return the information string of an edge.
470  const std::string infoString() const {
471  return (Twine(Removed ? "-" : " ") + (InMST ? " " : "*") +
472  (IsCritical ? "c" : " ") + " W=" + Twine(Weight)).str();
473  }
474 };
475 
476 // This class stores the auxiliary information for each BB.
477 struct BBInfo {
478  BBInfo *Group;
479  uint32_t Index;
480  uint32_t Rank = 0;
481 
482  BBInfo(unsigned IX) : Group(this), Index(IX) {}
483 
484  // Return the information string of this object.
485  const std::string infoString() const {
486  return (Twine("Index=") + Twine(Index)).str();
487  }
488 };
489 
490 // This class implements the CFG edges. Note the CFG can be a multi-graph.
491 template <class Edge, class BBInfo> class FuncPGOInstrumentation {
492 private:
493  Function &F;
494 
495  // A map that stores the Comdat group in function F.
496  std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers;
497 
498  void computeCFGHash();
499  void renameComdatFunction();
500 
501 public:
502  std::vector<std::vector<Instruction *>> ValueSites;
503  SelectInstVisitor SIVisitor;
504  MemIntrinsicVisitor MIVisitor;
505  std::string FuncName;
506  GlobalVariable *FuncNameVar;
507 
508  // CFG hash value for this function.
509  uint64_t FunctionHash = 0;
510 
511  // The Minimum Spanning Tree of function CFG.
513 
514  // Give an edge, find the BB that will be instrumented.
515  // Return nullptr if there is no BB to be instrumented.
516  BasicBlock *getInstrBB(Edge *E);
517 
518  // Return the auxiliary BB information.
519  BBInfo &getBBInfo(const BasicBlock *BB) const { return MST.getBBInfo(BB); }
520 
521  // Return the auxiliary BB information if available.
522  BBInfo *findBBInfo(const BasicBlock *BB) const { return MST.findBBInfo(BB); }
523 
524  // Dump edges and BB information.
525  void dumpInfo(std::string Str = "") const {
526  MST.dumpEdges(dbgs(), Twine("Dump Function ") + FuncName + " Hash: " +
527  Twine(FunctionHash) + "\t" + Str);
528  }
529 
530  FuncPGOInstrumentation(
531  Function &Func,
532  std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers,
533  bool CreateGlobalVar = false, BranchProbabilityInfo *BPI = nullptr,
534  BlockFrequencyInfo *BFI = nullptr)
535  : F(Func), ComdatMembers(ComdatMembers), ValueSites(IPVK_Last + 1),
536  SIVisitor(Func), MIVisitor(Func), MST(F, BPI, BFI) {
537  // This should be done before CFG hash computation.
538  SIVisitor.countSelects(Func);
539  MIVisitor.countMemIntrinsics(Func);
540  NumOfPGOSelectInsts += SIVisitor.getNumOfSelectInsts();
541  NumOfPGOMemIntrinsics += MIVisitor.getNumOfMemIntrinsics();
542  ValueSites[IPVK_IndirectCallTarget] = findIndirectCallSites(Func);
543  ValueSites[IPVK_MemOPSize] = MIVisitor.findMemIntrinsics(Func);
544 
545  FuncName = getPGOFuncName(F);
546  computeCFGHash();
547  if (!ComdatMembers.empty())
548  renameComdatFunction();
549  LLVM_DEBUG(dumpInfo("after CFGMST"));
550 
551  NumOfPGOBB += MST.BBInfos.size();
552  for (auto &E : MST.AllEdges) {
553  if (E->Removed)
554  continue;
555  NumOfPGOEdge++;
556  if (!E->InMST)
557  NumOfPGOInstrument++;
558  }
559 
560  if (CreateGlobalVar)
561  FuncNameVar = createPGOFuncNameVar(F, FuncName);
562  }
563 
564  // Return the number of profile counters needed for the function.
565  unsigned getNumCounters() {
566  unsigned NumCounters = 0;
567  for (auto &E : this->MST.AllEdges) {
568  if (!E->InMST && !E->Removed)
569  NumCounters++;
570  }
571  return NumCounters + SIVisitor.getNumOfSelectInsts();
572  }
573 };
574 
575 } // end anonymous namespace
576 
577 // Compute Hash value for the CFG: the lower 32 bits are CRC32 of the index
578 // value of each BB in the CFG. The higher 32 bits record the number of edges.
579 template <class Edge, class BBInfo>
580 void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() {
581  std::vector<char> Indexes;
582  JamCRC JC;
583  for (auto &BB : F) {
584  const TerminatorInst *TI = BB.getTerminator();
585  for (unsigned I = 0, E = TI->getNumSuccessors(); I != E; ++I) {
586  BasicBlock *Succ = TI->getSuccessor(I);
587  auto BI = findBBInfo(Succ);
588  if (BI == nullptr)
589  continue;
590  uint32_t Index = BI->Index;
591  for (int J = 0; J < 4; J++)
592  Indexes.push_back((char)(Index >> (J * 8)));
593  }
594  }
595  JC.update(Indexes);
596  FunctionHash = (uint64_t)SIVisitor.getNumOfSelectInsts() << 56 |
597  (uint64_t)ValueSites[IPVK_IndirectCallTarget].size() << 48 |
598  (uint64_t)MST.AllEdges.size() << 32 | JC.getCRC();
599  LLVM_DEBUG(dbgs() << "Function Hash Computation for " << F.getName() << ":\n"
600  << " CRC = " << JC.getCRC()
601  << ", Selects = " << SIVisitor.getNumOfSelectInsts()
602  << ", Edges = " << MST.AllEdges.size() << ", ICSites = "
603  << ValueSites[IPVK_IndirectCallTarget].size()
604  << ", Hash = " << FunctionHash << "\n";);
605 }
606 
607 // Check if we can safely rename this Comdat function.
608 static bool canRenameComdat(
609  Function &F,
610  std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers) {
611  if (!DoComdatRenaming || !canRenameComdatFunc(F, true))
612  return false;
613 
614  // FIXME: Current only handle those Comdat groups that only containing one
615  // function and function aliases.
616  // (1) For a Comdat group containing multiple functions, we need to have a
617  // unique postfix based on the hashes for each function. There is a
618  // non-trivial code refactoring to do this efficiently.
619  // (2) Variables can not be renamed, so we can not rename Comdat function in a
620  // group including global vars.
621  Comdat *C = F.getComdat();
622  for (auto &&CM : make_range(ComdatMembers.equal_range(C))) {
623  if (dyn_cast<GlobalAlias>(CM.second))
624  continue;
625  Function *FM = dyn_cast<Function>(CM.second);
626  if (FM != &F)
627  return false;
628  }
629  return true;
630 }
631 
632 // Append the CFGHash to the Comdat function name.
633 template <class Edge, class BBInfo>
634 void FuncPGOInstrumentation<Edge, BBInfo>::renameComdatFunction() {
635  if (!canRenameComdat(F, ComdatMembers))
636  return;
637  std::string OrigName = F.getName().str();
638  std::string NewFuncName =
639  Twine(F.getName() + "." + Twine(FunctionHash)).str();
640  F.setName(Twine(NewFuncName));
642  FuncName = Twine(FuncName + "." + Twine(FunctionHash)).str();
643  Comdat *NewComdat;
644  Module *M = F.getParent();
645  // For AvailableExternallyLinkage functions, change the linkage to
646  // LinkOnceODR and put them into comdat. This is because after renaming, there
647  // is no backup external copy available for the function.
648  if (!F.hasComdat()) {
650  NewComdat = M->getOrInsertComdat(StringRef(NewFuncName));
652  F.setComdat(NewComdat);
653  return;
654  }
655 
656  // This function belongs to a single function Comdat group.
657  Comdat *OrigComdat = F.getComdat();
658  std::string NewComdatName =
659  Twine(OrigComdat->getName() + "." + Twine(FunctionHash)).str();
660  NewComdat = M->getOrInsertComdat(StringRef(NewComdatName));
661  NewComdat->setSelectionKind(OrigComdat->getSelectionKind());
662 
663  for (auto &&CM : make_range(ComdatMembers.equal_range(OrigComdat))) {
664  if (GlobalAlias *GA = dyn_cast<GlobalAlias>(CM.second)) {
665  // For aliases, change the name directly.
666  assert(dyn_cast<Function>(GA->getAliasee()->stripPointerCasts()) == &F);
667  std::string OrigGAName = GA->getName().str();
668  GA->setName(Twine(GA->getName() + "." + Twine(FunctionHash)));
670  continue;
671  }
672  // Must be a function.
673  Function *CF = dyn_cast<Function>(CM.second);
674  assert(CF);
675  CF->setComdat(NewComdat);
676  }
677 }
678 
679 // Given a CFG E to be instrumented, find which BB to place the instrumented
680 // code. The function will split the critical edge if necessary.
681 template <class Edge, class BBInfo>
682 BasicBlock *FuncPGOInstrumentation<Edge, BBInfo>::getInstrBB(Edge *E) {
683  if (E->InMST || E->Removed)
684  return nullptr;
685 
686  BasicBlock *SrcBB = const_cast<BasicBlock *>(E->SrcBB);
687  BasicBlock *DestBB = const_cast<BasicBlock *>(E->DestBB);
688  // For a fake edge, instrument the real BB.
689  if (SrcBB == nullptr)
690  return DestBB;
691  if (DestBB == nullptr)
692  return SrcBB;
693 
694  // Instrument the SrcBB if it has a single successor,
695  // otherwise, the DestBB if this is not a critical edge.
696  TerminatorInst *TI = SrcBB->getTerminator();
697  if (TI->getNumSuccessors() <= 1)
698  return SrcBB;
699  if (!E->IsCritical)
700  return DestBB;
701 
702  // For a critical edge, we have to split. Instrument the newly
703  // created BB.
704  NumOfPGOSplit++;
705  LLVM_DEBUG(dbgs() << "Split critical edge: " << getBBInfo(SrcBB).Index
706  << " --> " << getBBInfo(DestBB).Index << "\n");
707  unsigned SuccNum = GetSuccessorNumber(SrcBB, DestBB);
708  BasicBlock *InstrBB = SplitCriticalEdge(TI, SuccNum);
709  assert(InstrBB && "Critical edge is not split");
710 
711  E->Removed = true;
712  return InstrBB;
713 }
714 
715 // Visit all edge and instrument the edges not in MST, and do value profiling.
716 // Critical edges will be split.
717 static void instrumentOneFunc(
719  std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers) {
720  // Split indirectbr critical edges here before computing the MST rather than
721  // later in getInstrBB() to avoid invalidating it.
722  SplitIndirectBrCriticalEdges(F, BPI, BFI);
723  FuncPGOInstrumentation<PGOEdge, BBInfo> FuncInfo(F, ComdatMembers, true, BPI,
724  BFI);
725  unsigned NumCounters = FuncInfo.getNumCounters();
726 
727  uint32_t I = 0;
728  Type *I8PtrTy = Type::getInt8PtrTy(M->getContext());
729  for (auto &E : FuncInfo.MST.AllEdges) {
730  BasicBlock *InstrBB = FuncInfo.getInstrBB(E.get());
731  if (!InstrBB)
732  continue;
733 
734  IRBuilder<> Builder(InstrBB, InstrBB->getFirstInsertionPt());
735  assert(Builder.GetInsertPoint() != InstrBB->end() &&
736  "Cannot get the Instrumentation point");
737  Builder.CreateCall(
738  Intrinsic::getDeclaration(M, Intrinsic::instrprof_increment),
739  {ConstantExpr::getBitCast(FuncInfo.FuncNameVar, I8PtrTy),
740  Builder.getInt64(FuncInfo.FunctionHash), Builder.getInt32(NumCounters),
741  Builder.getInt32(I++)});
742  }
743 
744  // Now instrument select instructions:
745  FuncInfo.SIVisitor.instrumentSelects(F, &I, NumCounters, FuncInfo.FuncNameVar,
746  FuncInfo.FunctionHash);
747  assert(I == NumCounters);
748 
750  return;
751 
752  unsigned NumIndirectCallSites = 0;
753  for (auto &I : FuncInfo.ValueSites[IPVK_IndirectCallTarget]) {
754  CallSite CS(I);
755  Value *Callee = CS.getCalledValue();
756  LLVM_DEBUG(dbgs() << "Instrument one indirect call: CallSite Index = "
757  << NumIndirectCallSites << "\n");
758  IRBuilder<> Builder(I);
759  assert(Builder.GetInsertPoint() != I->getParent()->end() &&
760  "Cannot get the Instrumentation point");
761  Builder.CreateCall(
762  Intrinsic::getDeclaration(M, Intrinsic::instrprof_value_profile),
763  {ConstantExpr::getBitCast(FuncInfo.FuncNameVar, I8PtrTy),
764  Builder.getInt64(FuncInfo.FunctionHash),
765  Builder.CreatePtrToInt(Callee, Builder.getInt64Ty()),
766  Builder.getInt32(IPVK_IndirectCallTarget),
767  Builder.getInt32(NumIndirectCallSites++)});
768  }
769  NumOfPGOICall += NumIndirectCallSites;
770 
771  // Now instrument memop intrinsic calls.
772  FuncInfo.MIVisitor.instrumentMemIntrinsics(
773  F, NumCounters, FuncInfo.FuncNameVar, FuncInfo.FunctionHash);
774 }
775 
776 namespace {
777 
778 // This class represents a CFG edge in profile use compilation.
779 struct PGOUseEdge : public PGOEdge {
780  bool CountValid = false;
781  uint64_t CountValue = 0;
782 
783  PGOUseEdge(const BasicBlock *Src, const BasicBlock *Dest, uint64_t W = 1)
784  : PGOEdge(Src, Dest, W) {}
785 
786  // Set edge count value
787  void setEdgeCount(uint64_t Value) {
788  CountValue = Value;
789  CountValid = true;
790  }
791 
792  // Return the information string for this object.
793  const std::string infoString() const {
794  if (!CountValid)
795  return PGOEdge::infoString();
796  return (Twine(PGOEdge::infoString()) + " Count=" + Twine(CountValue))
797  .str();
798  }
799 };
800 
801 using DirectEdges = SmallVector<PGOUseEdge *, 2>;
802 
803 // This class stores the auxiliary information for each BB.
804 struct UseBBInfo : public BBInfo {
805  uint64_t CountValue = 0;
806  bool CountValid;
807  int32_t UnknownCountInEdge = 0;
808  int32_t UnknownCountOutEdge = 0;
809  DirectEdges InEdges;
810  DirectEdges OutEdges;
811 
812  UseBBInfo(unsigned IX) : BBInfo(IX), CountValid(false) {}
813 
814  UseBBInfo(unsigned IX, uint64_t C)
815  : BBInfo(IX), CountValue(C), CountValid(true) {}
816 
817  // Set the profile count value for this BB.
818  void setBBInfoCount(uint64_t Value) {
819  CountValue = Value;
820  CountValid = true;
821  }
822 
823  // Return the information string of this object.
824  const std::string infoString() const {
825  if (!CountValid)
826  return BBInfo::infoString();
827  return (Twine(BBInfo::infoString()) + " Count=" + Twine(CountValue)).str();
828  }
829 };
830 
831 } // end anonymous namespace
832 
833 // Sum up the count values for all the edges.
834 static uint64_t sumEdgeCount(const ArrayRef<PGOUseEdge *> Edges) {
835  uint64_t Total = 0;
836  for (auto &E : Edges) {
837  if (E->Removed)
838  continue;
839  Total += E->CountValue;
840  }
841  return Total;
842 }
843 
844 namespace {
845 
846 class PGOUseFunc {
847 public:
848  PGOUseFunc(Function &Func, Module *Modu,
849  std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers,
850  BranchProbabilityInfo *BPI = nullptr,
851  BlockFrequencyInfo *BFIin = nullptr)
852  : F(Func), M(Modu), BFI(BFIin),
853  FuncInfo(Func, ComdatMembers, false, BPI, BFIin),
854  FreqAttr(FFA_Normal) {}
855 
856  // Read counts for the instrumented BB from profile.
857  bool readCounters(IndexedInstrProfReader *PGOReader);
858 
859  // Populate the counts for all BBs.
860  void populateCounters();
861 
862  // Set the branch weights based on the count values.
863  void setBranchWeights();
864 
865  // Annotate the value profile call sites for all value kind.
866  void annotateValueSites();
867 
868  // Annotate the value profile call sites for one value kind.
869  void annotateValueSites(uint32_t Kind);
870 
871  // Annotate the irreducible loop header weights.
872  void annotateIrrLoopHeaderWeights();
873 
874  // The hotness of the function from the profile count.
875  enum FuncFreqAttr { FFA_Normal, FFA_Cold, FFA_Hot };
876 
877  // Return the function hotness from the profile.
878  FuncFreqAttr getFuncFreqAttr() const { return FreqAttr; }
879 
880  // Return the function hash.
881  uint64_t getFuncHash() const { return FuncInfo.FunctionHash; }
882 
883  // Return the profile record for this function;
884  InstrProfRecord &getProfileRecord() { return ProfileRecord; }
885 
886  // Return the auxiliary BB information.
887  UseBBInfo &getBBInfo(const BasicBlock *BB) const {
888  return FuncInfo.getBBInfo(BB);
889  }
890 
891  // Return the auxiliary BB information if available.
892  UseBBInfo *findBBInfo(const BasicBlock *BB) const {
893  return FuncInfo.findBBInfo(BB);
894  }
895 
896  Function &getFunc() const { return F; }
897 
898  void dumpInfo(std::string Str = "") const {
899  FuncInfo.dumpInfo(Str);
900  }
901 
902 private:
903  Function &F;
904  Module *M;
906 
907  // This member stores the shared information with class PGOGenFunc.
908  FuncPGOInstrumentation<PGOUseEdge, UseBBInfo> FuncInfo;
909 
910  // The maximum count value in the profile. This is only used in PGO use
911  // compilation.
912  uint64_t ProgramMaxCount;
913 
914  // Position of counter that remains to be read.
915  uint32_t CountPosition = 0;
916 
917  // Total size of the profile count for this function.
918  uint32_t ProfileCountSize = 0;
919 
920  // ProfileRecord for this function.
921  InstrProfRecord ProfileRecord;
922 
923  // Function hotness info derived from profile.
924  FuncFreqAttr FreqAttr;
925 
926  // Find the Instrumented BB and set the value.
927  void setInstrumentedCounts(const std::vector<uint64_t> &CountFromProfile);
928 
929  // Set the edge counter value for the unknown edge -- there should be only
930  // one unknown edge.
931  void setEdgeCount(DirectEdges &Edges, uint64_t Value);
932 
933  // Return FuncName string;
934  const std::string getFuncName() const { return FuncInfo.FuncName; }
935 
936  // Set the hot/cold inline hints based on the count values.
937  // FIXME: This function should be removed once the functionality in
938  // the inliner is implemented.
939  void markFunctionAttributes(uint64_t EntryCount, uint64_t MaxCount) {
940  if (ProgramMaxCount == 0)
941  return;
942  // Threshold of the hot functions.
943  const BranchProbability HotFunctionThreshold(1, 100);
944  // Threshold of the cold functions.
945  const BranchProbability ColdFunctionThreshold(2, 10000);
946  if (EntryCount >= HotFunctionThreshold.scale(ProgramMaxCount))
947  FreqAttr = FFA_Hot;
948  else if (MaxCount <= ColdFunctionThreshold.scale(ProgramMaxCount))
949  FreqAttr = FFA_Cold;
950  }
951 };
952 
953 } // end anonymous namespace
954 
955 // Visit all the edges and assign the count value for the instrumented
956 // edges and the BB.
957 void PGOUseFunc::setInstrumentedCounts(
958  const std::vector<uint64_t> &CountFromProfile) {
959  assert(FuncInfo.getNumCounters() == CountFromProfile.size());
960  // Use a worklist as we will update the vector during the iteration.
961  std::vector<PGOUseEdge *> WorkList;
962  for (auto &E : FuncInfo.MST.AllEdges)
963  WorkList.push_back(E.get());
964 
965  uint32_t I = 0;
966  for (auto &E : WorkList) {
967  BasicBlock *InstrBB = FuncInfo.getInstrBB(E);
968  if (!InstrBB)
969  continue;
970  uint64_t CountValue = CountFromProfile[I++];
971  if (!E->Removed) {
972  getBBInfo(InstrBB).setBBInfoCount(CountValue);
973  E->setEdgeCount(CountValue);
974  continue;
975  }
976 
977  // Need to add two new edges.
978  BasicBlock *SrcBB = const_cast<BasicBlock *>(E->SrcBB);
979  BasicBlock *DestBB = const_cast<BasicBlock *>(E->DestBB);
980  // Add new edge of SrcBB->InstrBB.
981  PGOUseEdge &NewEdge = FuncInfo.MST.addEdge(SrcBB, InstrBB, 0);
982  NewEdge.setEdgeCount(CountValue);
983  // Add new edge of InstrBB->DestBB.
984  PGOUseEdge &NewEdge1 = FuncInfo.MST.addEdge(InstrBB, DestBB, 0);
985  NewEdge1.setEdgeCount(CountValue);
986  NewEdge1.InMST = true;
987  getBBInfo(InstrBB).setBBInfoCount(CountValue);
988  }
989  ProfileCountSize = CountFromProfile.size();
990  CountPosition = I;
991 }
992 
993 // Set the count value for the unknown edge. There should be one and only one
994 // unknown edge in Edges vector.
995 void PGOUseFunc::setEdgeCount(DirectEdges &Edges, uint64_t Value) {
996  for (auto &E : Edges) {
997  if (E->CountValid)
998  continue;
999  E->setEdgeCount(Value);
1000 
1001  getBBInfo(E->SrcBB).UnknownCountOutEdge--;
1002  getBBInfo(E->DestBB).UnknownCountInEdge--;
1003  return;
1004  }
1005  llvm_unreachable("Cannot find the unknown count edge");
1006 }
1007 
1008 // Read the profile from ProfileFileName and assign the value to the
1009 // instrumented BB and the edges. This function also updates ProgramMaxCount.
1010 // Return true if the profile are successfully read, and false on errors.
1011 bool PGOUseFunc::readCounters(IndexedInstrProfReader *PGOReader) {
1012  auto &Ctx = M->getContext();
1013  Expected<InstrProfRecord> Result =
1014  PGOReader->getInstrProfRecord(FuncInfo.FuncName, FuncInfo.FunctionHash);
1015  if (Error E = Result.takeError()) {
1016  handleAllErrors(std::move(E), [&](const InstrProfError &IPE) {
1017  auto Err = IPE.get();
1018  bool SkipWarning = false;
1019  if (Err == instrprof_error::unknown_function) {
1020  NumOfPGOMissing++;
1021  SkipWarning = !PGOWarnMissing;
1022  } else if (Err == instrprof_error::hash_mismatch ||
1023  Err == instrprof_error::malformed) {
1024  NumOfPGOMismatch++;
1025  SkipWarning =
1028  (F.hasComdat() ||
1029  F.getLinkage() == GlobalValue::AvailableExternallyLinkage));
1030  }
1031 
1032  if (SkipWarning)
1033  return;
1034 
1035  std::string Msg = IPE.message() + std::string(" ") + F.getName().str();
1036  Ctx.diagnose(
1037  DiagnosticInfoPGOProfile(M->getName().data(), Msg, DS_Warning));
1038  });
1039  return false;
1040  }
1041  ProfileRecord = std::move(Result.get());
1042  std::vector<uint64_t> &CountFromProfile = ProfileRecord.Counts;
1043 
1044  NumOfPGOFunc++;
1045  LLVM_DEBUG(dbgs() << CountFromProfile.size() << " counts\n");
1046  uint64_t ValueSum = 0;
1047  for (unsigned I = 0, S = CountFromProfile.size(); I < S; I++) {
1048  LLVM_DEBUG(dbgs() << " " << I << ": " << CountFromProfile[I] << "\n");
1049  ValueSum += CountFromProfile[I];
1050  }
1051 
1052  LLVM_DEBUG(dbgs() << "SUM = " << ValueSum << "\n");
1053 
1054  getBBInfo(nullptr).UnknownCountOutEdge = 2;
1055  getBBInfo(nullptr).UnknownCountInEdge = 2;
1056 
1057  setInstrumentedCounts(CountFromProfile);
1058  ProgramMaxCount = PGOReader->getMaximumFunctionCount();
1059  return true;
1060 }
1061 
1062 // Populate the counters from instrumented BBs to all BBs.
1063 // In the end of this operation, all BBs should have a valid count value.
1064 void PGOUseFunc::populateCounters() {
1065  // First set up Count variable for all BBs.
1066  for (auto &E : FuncInfo.MST.AllEdges) {
1067  if (E->Removed)
1068  continue;
1069 
1070  const BasicBlock *SrcBB = E->SrcBB;
1071  const BasicBlock *DestBB = E->DestBB;
1072  UseBBInfo &SrcInfo = getBBInfo(SrcBB);
1073  UseBBInfo &DestInfo = getBBInfo(DestBB);
1074  SrcInfo.OutEdges.push_back(E.get());
1075  DestInfo.InEdges.push_back(E.get());
1076  SrcInfo.UnknownCountOutEdge++;
1077  DestInfo.UnknownCountInEdge++;
1078 
1079  if (!E->CountValid)
1080  continue;
1081  DestInfo.UnknownCountInEdge--;
1082  SrcInfo.UnknownCountOutEdge--;
1083  }
1084 
1085  bool Changes = true;
1086  unsigned NumPasses = 0;
1087  while (Changes) {
1088  NumPasses++;
1089  Changes = false;
1090 
1091  // For efficient traversal, it's better to start from the end as most
1092  // of the instrumented edges are at the end.
1093  for (auto &BB : reverse(F)) {
1094  UseBBInfo *Count = findBBInfo(&BB);
1095  if (Count == nullptr)
1096  continue;
1097  if (!Count->CountValid) {
1098  if (Count->UnknownCountOutEdge == 0) {
1099  Count->CountValue = sumEdgeCount(Count->OutEdges);
1100  Count->CountValid = true;
1101  Changes = true;
1102  } else if (Count->UnknownCountInEdge == 0) {
1103  Count->CountValue = sumEdgeCount(Count->InEdges);
1104  Count->CountValid = true;
1105  Changes = true;
1106  }
1107  }
1108  if (Count->CountValid) {
1109  if (Count->UnknownCountOutEdge == 1) {
1110  uint64_t Total = 0;
1111  uint64_t OutSum = sumEdgeCount(Count->OutEdges);
1112  // If the one of the successor block can early terminate (no-return),
1113  // we can end up with situation where out edge sum count is larger as
1114  // the source BB's count is collected by a post-dominated block.
1115  if (Count->CountValue > OutSum)
1116  Total = Count->CountValue - OutSum;
1117  setEdgeCount(Count->OutEdges, Total);
1118  Changes = true;
1119  }
1120  if (Count->UnknownCountInEdge == 1) {
1121  uint64_t Total = 0;
1122  uint64_t InSum = sumEdgeCount(Count->InEdges);
1123  if (Count->CountValue > InSum)
1124  Total = Count->CountValue - InSum;
1125  setEdgeCount(Count->InEdges, Total);
1126  Changes = true;
1127  }
1128  }
1129  }
1130  }
1131 
1132  LLVM_DEBUG(dbgs() << "Populate counts in " << NumPasses << " passes.\n");
1133 #ifndef NDEBUG
1134  // Assert every BB has a valid counter.
1135  for (auto &BB : F) {
1136  auto BI = findBBInfo(&BB);
1137  if (BI == nullptr)
1138  continue;
1139  assert(BI->CountValid && "BB count is not valid");
1140  }
1141 #endif
1142  uint64_t FuncEntryCount = getBBInfo(&*F.begin()).CountValue;
1143  F.setEntryCount(ProfileCount(FuncEntryCount, Function::PCT_Real));
1144  uint64_t FuncMaxCount = FuncEntryCount;
1145  for (auto &BB : F) {
1146  auto BI = findBBInfo(&BB);
1147  if (BI == nullptr)
1148  continue;
1149  FuncMaxCount = std::max(FuncMaxCount, BI->CountValue);
1150  }
1151  markFunctionAttributes(FuncEntryCount, FuncMaxCount);
1152 
1153  // Now annotate select instructions
1154  FuncInfo.SIVisitor.annotateSelects(F, this, &CountPosition);
1155  assert(CountPosition == ProfileCountSize);
1156 
1157  LLVM_DEBUG(FuncInfo.dumpInfo("after reading profile."));
1158 }
1159 
1160 // Assign the scaled count values to the BB with multiple out edges.
1162  // Generate MD_prof metadata for every branch instruction.
1163  LLVM_DEBUG(dbgs() << "\nSetting branch weights.\n");
1164  for (auto &BB : F) {
1165  TerminatorInst *TI = BB.getTerminator();
1166  if (TI->getNumSuccessors() < 2)
1167  continue;
1168  if (!(isa<BranchInst>(TI) || isa<SwitchInst>(TI) ||
1169  isa<IndirectBrInst>(TI)))
1170  continue;
1171  if (getBBInfo(&BB).CountValue == 0)
1172  continue;
1173 
1174  // We have a non-zero Branch BB.
1175  const UseBBInfo &BBCountInfo = getBBInfo(&BB);
1176  unsigned Size = BBCountInfo.OutEdges.size();
1177  SmallVector<uint64_t, 2> EdgeCounts(Size, 0);
1178  uint64_t MaxCount = 0;
1179  for (unsigned s = 0; s < Size; s++) {
1180  const PGOUseEdge *E = BBCountInfo.OutEdges[s];
1181  const BasicBlock *SrcBB = E->SrcBB;
1182  const BasicBlock *DestBB = E->DestBB;
1183  if (DestBB == nullptr)
1184  continue;
1185  unsigned SuccNum = GetSuccessorNumber(SrcBB, DestBB);
1186  uint64_t EdgeCount = E->CountValue;
1187  if (EdgeCount > MaxCount)
1188  MaxCount = EdgeCount;
1189  EdgeCounts[SuccNum] = EdgeCount;
1190  }
1191  setProfMetadata(M, TI, EdgeCounts, MaxCount);
1192  }
1193 }
1194 
1195 static bool isIndirectBrTarget(BasicBlock *BB) {
1196  for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
1197  if (isa<IndirectBrInst>((*PI)->getTerminator()))
1198  return true;
1199  }
1200  return false;
1201 }
1202 
1203 void PGOUseFunc::annotateIrrLoopHeaderWeights() {
1204  LLVM_DEBUG(dbgs() << "\nAnnotating irreducible loop header weights.\n");
1205  // Find irr loop headers
1206  for (auto &BB : F) {
1207  // As a heuristic also annotate indrectbr targets as they have a high chance
1208  // to become an irreducible loop header after the indirectbr tail
1209  // duplication.
1210  if (BFI->isIrrLoopHeader(&BB) || isIndirectBrTarget(&BB)) {
1211  TerminatorInst *TI = BB.getTerminator();
1212  const UseBBInfo &BBCountInfo = getBBInfo(&BB);
1213  setIrrLoopHeaderMetadata(M, TI, BBCountInfo.CountValue);
1214  }
1215  }
1216 }
1217 
1218 void SelectInstVisitor::instrumentOneSelectInst(SelectInst &SI) {
1219  Module *M = F.getParent();
1220  IRBuilder<> Builder(&SI);
1221  Type *Int64Ty = Builder.getInt64Ty();
1222  Type *I8PtrTy = Builder.getInt8PtrTy();
1223  auto *Step = Builder.CreateZExt(SI.getCondition(), Int64Ty);
1224  Builder.CreateCall(
1225  Intrinsic::getDeclaration(M, Intrinsic::instrprof_increment_step),
1226  {ConstantExpr::getBitCast(FuncNameVar, I8PtrTy),
1227  Builder.getInt64(FuncHash), Builder.getInt32(TotalNumCtrs),
1228  Builder.getInt32(*CurCtrIdx), Step});
1229  ++(*CurCtrIdx);
1230 }
1231 
1232 void SelectInstVisitor::annotateOneSelectInst(SelectInst &SI) {
1233  std::vector<uint64_t> &CountFromProfile = UseFunc->getProfileRecord().Counts;
1234  assert(*CurCtrIdx < CountFromProfile.size() &&
1235  "Out of bound access of counters");
1236  uint64_t SCounts[2];
1237  SCounts[0] = CountFromProfile[*CurCtrIdx]; // True count
1238  ++(*CurCtrIdx);
1239  uint64_t TotalCount = 0;
1240  auto BI = UseFunc->findBBInfo(SI.getParent());
1241  if (BI != nullptr)
1242  TotalCount = BI->CountValue;
1243  // False Count
1244  SCounts[1] = (TotalCount > SCounts[0] ? TotalCount - SCounts[0] : 0);
1245  uint64_t MaxCount = std::max(SCounts[0], SCounts[1]);
1246  if (MaxCount)
1247  setProfMetadata(F.getParent(), &SI, SCounts, MaxCount);
1248 }
1249 
1250 void SelectInstVisitor::visitSelectInst(SelectInst &SI) {
1251  if (!PGOInstrSelect)
1252  return;
1253  // FIXME: do not handle this yet.
1254  if (SI.getCondition()->getType()->isVectorTy())
1255  return;
1256 
1257  switch (Mode) {
1258  case VM_counting:
1259  NSIs++;
1260  return;
1261  case VM_instrument:
1262  instrumentOneSelectInst(SI);
1263  return;
1264  case VM_annotate:
1265  annotateOneSelectInst(SI);
1266  return;
1267  }
1268 
1269  llvm_unreachable("Unknown visiting mode");
1270 }
1271 
1272 void MemIntrinsicVisitor::instrumentOneMemIntrinsic(MemIntrinsic &MI) {
1273  Module *M = F.getParent();
1274  IRBuilder<> Builder(&MI);
1275  Type *Int64Ty = Builder.getInt64Ty();
1276  Type *I8PtrTy = Builder.getInt8PtrTy();
1277  Value *Length = MI.getLength();
1278  assert(!dyn_cast<ConstantInt>(Length));
1279  Builder.CreateCall(
1280  Intrinsic::getDeclaration(M, Intrinsic::instrprof_value_profile),
1281  {ConstantExpr::getBitCast(FuncNameVar, I8PtrTy),
1282  Builder.getInt64(FuncHash), Builder.CreateZExtOrTrunc(Length, Int64Ty),
1283  Builder.getInt32(IPVK_MemOPSize), Builder.getInt32(CurCtrId)});
1284  ++CurCtrId;
1285 }
1286 
1287 void MemIntrinsicVisitor::visitMemIntrinsic(MemIntrinsic &MI) {
1288  if (!PGOInstrMemOP)
1289  return;
1290  Value *Length = MI.getLength();
1291  // Not instrument constant length calls.
1292  if (dyn_cast<ConstantInt>(Length))
1293  return;
1294 
1295  switch (Mode) {
1296  case VM_counting:
1297  NMemIs++;
1298  return;
1299  case VM_instrument:
1300  instrumentOneMemIntrinsic(MI);
1301  return;
1302  case VM_annotate:
1303  Candidates.push_back(&MI);
1304  return;
1305  }
1306  llvm_unreachable("Unknown visiting mode");
1307 }
1308 
1309 // Traverse all valuesites and annotate the instructions for all value kind.
1310 void PGOUseFunc::annotateValueSites() {
1312  return;
1313 
1314  // Create the PGOFuncName meta data.
1315  createPGOFuncNameMetadata(F, FuncInfo.FuncName);
1316 
1317  for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
1318  annotateValueSites(Kind);
1319 }
1320 
1321 // Annotate the instructions for a specific value kind.
1322 void PGOUseFunc::annotateValueSites(uint32_t Kind) {
1323  unsigned ValueSiteIndex = 0;
1324  auto &ValueSites = FuncInfo.ValueSites[Kind];
1325  unsigned NumValueSites = ProfileRecord.getNumValueSites(Kind);
1326  if (NumValueSites != ValueSites.size()) {
1327  auto &Ctx = M->getContext();
1328  Ctx.diagnose(DiagnosticInfoPGOProfile(
1329  M->getName().data(),
1330  Twine("Inconsistent number of value sites for kind = ") + Twine(Kind) +
1331  " in " + F.getName().str(),
1332  DS_Warning));
1333  return;
1334  }
1335 
1336  for (auto &I : ValueSites) {
1337  LLVM_DEBUG(dbgs() << "Read one value site profile (kind = " << Kind
1338  << "): Index = " << ValueSiteIndex << " out of "
1339  << NumValueSites << "\n");
1340  annotateValueSite(*M, *I, ProfileRecord,
1341  static_cast<InstrProfValueKind>(Kind), ValueSiteIndex,
1342  Kind == IPVK_MemOPSize ? MaxNumMemOPAnnotations
1343  : MaxNumAnnotations);
1344  ValueSiteIndex++;
1345  }
1346 }
1347 
1348 // Create a COMDAT variable INSTR_PROF_RAW_VERSION_VAR to make the runtime
1349 // aware this is an ir_level profile so it can set the version flag.
1351  Type *IntTy64 = Type::getInt64Ty(M.getContext());
1352  uint64_t ProfileVersion = (INSTR_PROF_RAW_VERSION | VARIANT_MASK_IR_PROF);
1353  auto IRLevelVersionVariable = new GlobalVariable(
1354  M, IntTy64, true, GlobalVariable::ExternalLinkage,
1355  Constant::getIntegerValue(IntTy64, APInt(64, ProfileVersion)),
1356  INSTR_PROF_QUOTE(INSTR_PROF_RAW_VERSION_VAR));
1357  IRLevelVersionVariable->setVisibility(GlobalValue::DefaultVisibility);
1358  Triple TT(M.getTargetTriple());
1359  if (!TT.supportsCOMDAT())
1360  IRLevelVersionVariable->setLinkage(GlobalValue::WeakAnyLinkage);
1361  else
1362  IRLevelVersionVariable->setComdat(M.getOrInsertComdat(
1363  StringRef(INSTR_PROF_QUOTE(INSTR_PROF_RAW_VERSION_VAR))));
1364 }
1365 
1366 // Collect the set of members for each Comdat in module M and store
1367 // in ComdatMembers.
1369  Module &M,
1370  std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers) {
1371  if (!DoComdatRenaming)
1372  return;
1373  for (Function &F : M)
1374  if (Comdat *C = F.getComdat())
1375  ComdatMembers.insert(std::make_pair(C, &F));
1376  for (GlobalVariable &GV : M.globals())
1377  if (Comdat *C = GV.getComdat())
1378  ComdatMembers.insert(std::make_pair(C, &GV));
1379  for (GlobalAlias &GA : M.aliases())
1380  if (Comdat *C = GA.getComdat())
1381  ComdatMembers.insert(std::make_pair(C, &GA));
1382 }
1383 
1385  Module &M, function_ref<BranchProbabilityInfo *(Function &)> LookupBPI,
1386  function_ref<BlockFrequencyInfo *(Function &)> LookupBFI) {
1388  std::unordered_multimap<Comdat *, GlobalValue *> ComdatMembers;
1389  collectComdatMembers(M, ComdatMembers);
1390 
1391  for (auto &F : M) {
1392  if (F.isDeclaration())
1393  continue;
1394  auto *BPI = LookupBPI(F);
1395  auto *BFI = LookupBFI(F);
1396  instrumentOneFunc(F, &M, BPI, BFI, ComdatMembers);
1397  }
1398  return true;
1399 }
1400 
1401 bool PGOInstrumentationGenLegacyPass::runOnModule(Module &M) {
1402  if (skipModule(M))
1403  return false;
1404 
1405  auto LookupBPI = [this](Function &F) {
1406  return &this->getAnalysis<BranchProbabilityInfoWrapperPass>(F).getBPI();
1407  };
1408  auto LookupBFI = [this](Function &F) {
1409  return &this->getAnalysis<BlockFrequencyInfoWrapperPass>(F).getBFI();
1410  };
1411  return InstrumentAllFunctions(M, LookupBPI, LookupBFI);
1412 }
1413 
1415  ModuleAnalysisManager &AM) {
1416  auto &FAM = AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
1417  auto LookupBPI = [&FAM](Function &F) {
1418  return &FAM.getResult<BranchProbabilityAnalysis>(F);
1419  };
1420 
1421  auto LookupBFI = [&FAM](Function &F) {
1422  return &FAM.getResult<BlockFrequencyAnalysis>(F);
1423  };
1424 
1425  if (!InstrumentAllFunctions(M, LookupBPI, LookupBFI))
1426  return PreservedAnalyses::all();
1427 
1428  return PreservedAnalyses::none();
1429 }
1430 
1432  Module &M, StringRef ProfileFileName,
1434  function_ref<BlockFrequencyInfo *(Function &)> LookupBFI) {
1435  LLVM_DEBUG(dbgs() << "Read in profile counters: ");
1436  auto &Ctx = M.getContext();
1437  // Read the counter array from file.
1438  auto ReaderOrErr = IndexedInstrProfReader::create(ProfileFileName);
1439  if (Error E = ReaderOrErr.takeError()) {
1440  handleAllErrors(std::move(E), [&](const ErrorInfoBase &EI) {
1441  Ctx.diagnose(
1442  DiagnosticInfoPGOProfile(ProfileFileName.data(), EI.message()));
1443  });
1444  return false;
1445  }
1446 
1447  std::unique_ptr<IndexedInstrProfReader> PGOReader =
1448  std::move(ReaderOrErr.get());
1449  if (!PGOReader) {
1450  Ctx.diagnose(DiagnosticInfoPGOProfile(ProfileFileName.data(),
1451  StringRef("Cannot get PGOReader")));
1452  return false;
1453  }
1454  // TODO: might need to change the warning once the clang option is finalized.
1455  if (!PGOReader->isIRLevelProfile()) {
1456  Ctx.diagnose(DiagnosticInfoPGOProfile(
1457  ProfileFileName.data(), "Not an IR level instrumentation profile"));
1458  return false;
1459  }
1460 
1461  std::unordered_multimap<Comdat *, GlobalValue *> ComdatMembers;
1462  collectComdatMembers(M, ComdatMembers);
1463  std::vector<Function *> HotFunctions;
1464  std::vector<Function *> ColdFunctions;
1465  for (auto &F : M) {
1466  if (F.isDeclaration())
1467  continue;
1468  auto *BPI = LookupBPI(F);
1469  auto *BFI = LookupBFI(F);
1470  // Split indirectbr critical edges here before computing the MST rather than
1471  // later in getInstrBB() to avoid invalidating it.
1473  PGOUseFunc Func(F, &M, ComdatMembers, BPI, BFI);
1474  if (!Func.readCounters(PGOReader.get()))
1475  continue;
1476  Func.populateCounters();
1477  Func.setBranchWeights();
1478  Func.annotateValueSites();
1479  Func.annotateIrrLoopHeaderWeights();
1480  PGOUseFunc::FuncFreqAttr FreqAttr = Func.getFuncFreqAttr();
1481  if (FreqAttr == PGOUseFunc::FFA_Cold)
1482  ColdFunctions.push_back(&F);
1483  else if (FreqAttr == PGOUseFunc::FFA_Hot)
1484  HotFunctions.push_back(&F);
1485  if (PGOViewCounts != PGOVCT_None &&
1486  (ViewBlockFreqFuncName.empty() ||
1487  F.getName().equals(ViewBlockFreqFuncName))) {
1488  LoopInfo LI{DominatorTree(F)};
1489  std::unique_ptr<BranchProbabilityInfo> NewBPI =
1490  llvm::make_unique<BranchProbabilityInfo>(F, LI);
1491  std::unique_ptr<BlockFrequencyInfo> NewBFI =
1492  llvm::make_unique<BlockFrequencyInfo>(F, *NewBPI, LI);
1493  if (PGOViewCounts == PGOVCT_Graph)
1494  NewBFI->view();
1495  else if (PGOViewCounts == PGOVCT_Text) {
1496  dbgs() << "pgo-view-counts: " << Func.getFunc().getName() << "\n";
1497  NewBFI->print(dbgs());
1498  }
1499  }
1500  if (PGOViewRawCounts != PGOVCT_None &&
1501  (ViewBlockFreqFuncName.empty() ||
1502  F.getName().equals(ViewBlockFreqFuncName))) {
1504  if (ViewBlockFreqFuncName.empty())
1505  WriteGraph(&Func, Twine("PGORawCounts_") + Func.getFunc().getName());
1506  else
1507  ViewGraph(&Func, Twine("PGORawCounts_") + Func.getFunc().getName());
1508  else if (PGOViewRawCounts == PGOVCT_Text) {
1509  dbgs() << "pgo-view-raw-counts: " << Func.getFunc().getName() << "\n";
1510  Func.dumpInfo();
1511  }
1512  }
1513  }
1514  M.setProfileSummary(PGOReader->getSummary().getMD(M.getContext()));
1515  // Set function hotness attribute from the profile.
1516  // We have to apply these attributes at the end because their presence
1517  // can affect the BranchProbabilityInfo of any callers, resulting in an
1518  // inconsistent MST between prof-gen and prof-use.
1519  for (auto &F : HotFunctions) {
1520  F->addFnAttr(Attribute::InlineHint);
1521  LLVM_DEBUG(dbgs() << "Set inline attribute to function: " << F->getName()
1522  << "\n");
1523  }
1524  for (auto &F : ColdFunctions) {
1525  F->addFnAttr(Attribute::Cold);
1526  LLVM_DEBUG(dbgs() << "Set cold attribute to function: " << F->getName()
1527  << "\n");
1528  }
1529  return true;
1530 }
1531 
1533  : ProfileFileName(std::move(Filename)) {
1534  if (!PGOTestProfileFile.empty())
1535  ProfileFileName = PGOTestProfileFile;
1536 }
1537 
1539  ModuleAnalysisManager &AM) {
1540 
1541  auto &FAM = AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
1542  auto LookupBPI = [&FAM](Function &F) {
1543  return &FAM.getResult<BranchProbabilityAnalysis>(F);
1544  };
1545 
1546  auto LookupBFI = [&FAM](Function &F) {
1547  return &FAM.getResult<BlockFrequencyAnalysis>(F);
1548  };
1549 
1550  if (!annotateAllFunctions(M, ProfileFileName, LookupBPI, LookupBFI))
1551  return PreservedAnalyses::all();
1552 
1553  return PreservedAnalyses::none();
1554 }
1555 
1556 bool PGOInstrumentationUseLegacyPass::runOnModule(Module &M) {
1557  if (skipModule(M))
1558  return false;
1559 
1560  auto LookupBPI = [this](Function &F) {
1561  return &this->getAnalysis<BranchProbabilityInfoWrapperPass>(F).getBPI();
1562  };
1563  auto LookupBFI = [this](Function &F) {
1564  return &this->getAnalysis<BlockFrequencyInfoWrapperPass>(F).getBFI();
1565  };
1566 
1567  return annotateAllFunctions(M, ProfileFileName, LookupBPI, LookupBFI);
1568 }
1569 
1570 static std::string getSimpleNodeName(const BasicBlock *Node) {
1571  if (!Node->getName().empty())
1572  return Node->getName();
1573 
1574  std::string SimpleNodeName;
1575  raw_string_ostream OS(SimpleNodeName);
1576  Node->printAsOperand(OS, false);
1577  return OS.str();
1578 }
1579 
1581  ArrayRef<uint64_t> EdgeCounts,
1582  uint64_t MaxCount) {
1583  MDBuilder MDB(M->getContext());
1584  assert(MaxCount > 0 && "Bad max count");
1585  uint64_t Scale = calculateCountScale(MaxCount);
1586  SmallVector<unsigned, 4> Weights;
1587  for (const auto &ECI : EdgeCounts)
1588  Weights.push_back(scaleBranchCount(ECI, Scale));
1589 
1590  LLVM_DEBUG(dbgs() << "Weight is: "; for (const auto &W
1591  : Weights) {
1592  dbgs() << W << " ";
1593  } dbgs() << "\n";);
1594  TI->setMetadata(LLVMContext::MD_prof, MDB.createBranchWeights(Weights));
1595  if (EmitBranchProbability) {
1596  std::string BrCondStr = getBranchCondString(TI);
1597  if (BrCondStr.empty())
1598  return;
1599 
1600  uint64_t WSum =
1601  std::accumulate(Weights.begin(), Weights.end(), (uint64_t)0,
1602  [](uint64_t w1, uint64_t w2) { return w1 + w2; });
1603  uint64_t TotalCount =
1604  std::accumulate(EdgeCounts.begin(), EdgeCounts.end(), (uint64_t)0,
1605  [](uint64_t c1, uint64_t c2) { return c1 + c2; });
1606  Scale = calculateCountScale(WSum);
1607  BranchProbability BP(scaleBranchCount(Weights[0], Scale),
1608  scaleBranchCount(WSum, Scale));
1609  std::string BranchProbStr;
1610  raw_string_ostream OS(BranchProbStr);
1611  OS << BP;
1612  OS << " (total count : " << TotalCount << ")";
1613  OS.flush();
1614  Function *F = TI->getParent()->getParent();
1616  ORE.emit([&]() {
1617  return OptimizationRemark(DEBUG_TYPE, "pgo-instrumentation", TI)
1618  << BrCondStr << " is true with probability : " << BranchProbStr;
1619  });
1620  }
1621 }
1622 
1623 namespace llvm {
1624 
1625 void setIrrLoopHeaderMetadata(Module *M, Instruction *TI, uint64_t Count) {
1626  MDBuilder MDB(M->getContext());
1628  MDB.createIrrLoopHeaderWeight(Count));
1629 }
1630 
1631 template <> struct GraphTraits<PGOUseFunc *> {
1632  using NodeRef = const BasicBlock *;
1635 
1636  static NodeRef getEntryNode(const PGOUseFunc *G) {
1637  return &G->getFunc().front();
1638  }
1639 
1641  return succ_begin(N);
1642  }
1643 
1644  static ChildIteratorType child_end(const NodeRef N) { return succ_end(N); }
1645 
1646  static nodes_iterator nodes_begin(const PGOUseFunc *G) {
1647  return nodes_iterator(G->getFunc().begin());
1648  }
1649 
1650  static nodes_iterator nodes_end(const PGOUseFunc *G) {
1651  return nodes_iterator(G->getFunc().end());
1652  }
1653 };
1654 
1655 template <> struct DOTGraphTraits<PGOUseFunc *> : DefaultDOTGraphTraits {
1656  explicit DOTGraphTraits(bool isSimple = false)
1658 
1659  static std::string getGraphName(const PGOUseFunc *G) {
1660  return G->getFunc().getName();
1661  }
1662 
1663  std::string getNodeLabel(const BasicBlock *Node, const PGOUseFunc *Graph) {
1664  std::string Result;
1665  raw_string_ostream OS(Result);
1666 
1667  OS << getSimpleNodeName(Node) << ":\\l";
1668  UseBBInfo *BI = Graph->findBBInfo(Node);
1669  OS << "Count : ";
1670  if (BI && BI->CountValid)
1671  OS << BI->CountValue << "\\l";
1672  else
1673  OS << "Unknown\\l";
1674 
1675  if (!PGOInstrSelect)
1676  return Result;
1677 
1678  for (auto BI = Node->begin(); BI != Node->end(); ++BI) {
1679  auto *I = &*BI;
1680  if (!isa<SelectInst>(I))
1681  continue;
1682  // Display scaled counts for SELECT instruction:
1683  OS << "SELECT : { T = ";
1684  uint64_t TC, FC;
1685  bool HasProf = I->extractProfMetadata(TC, FC);
1686  if (!HasProf)
1687  OS << "Unknown, F = Unknown }\\l";
1688  else
1689  OS << TC << ", F = " << FC << " }\\l";
1690  }
1691  return Result;
1692  }
1693 };
1694 
1695 } // end namespace llvm
uint64_t CallInst * C
static uint64_t sumEdgeCount(const ArrayRef< PGOUseEdge *> Edges)
void push_back(const T &Elt)
Definition: SmallVector.h:213
uint32_t getCRC() const
Definition: JamCRC.h:42
const std::string & getTargetTriple() const
Get the target triple which is a string describing the target host.
Definition: Module.h:238
void setProfMetadata(Module *M, Instruction *TI, ArrayRef< uint64_t > EdgeCounts, uint64_t MaxCount)
ModulePass * createPGOInstrumentationGenLegacyPass()
static cl::opt< bool > NoPGOWarnMismatch("no-pgo-warn-mismatch", cl::init(false), cl::Hidden, cl::desc("Use this option to turn off/on " "warnings about profile cfg mismatch."))
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
GCNRegPressure max(const GCNRegPressure &P1, const GCNRegPressure &P2)
Base class for instruction visitors.
Definition: InstVisitor.h:81
SI Whole Quad Mode
Value * CreateZExtOrTrunc(Value *V, Type *DestTy, const Twine &Name="")
Create a ZExt or Trunc from the integer value V to DestTy.
Definition: IRBuilder.h:1566
PassT::Result & getResult(IRUnitT &IR, ExtraArgTs... ExtraArgs)
Get the result of an analysis pass for a given IR unit.
Definition: PassManager.h:687
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
static cl::opt< bool > PGOWarnMissing("pgo-warn-missing-function", cl::init(false), cl::Hidden, cl::desc("Use this option to turn on/off " "warnings about missing profile data for " "functions."))
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:63
BasicBlock * getSuccessor(unsigned idx) const
Return the specified successor.
static ChildIteratorType child_begin(const NodeRef N)
std::vector< std::unique_ptr< Edge > > AllEdges
Definition: CFGMST.h:44
Diagnostic information for the PGO profiler.
Available for inspection, not emission.
Definition: GlobalValue.h:50
std::string getNodeLabel(const BasicBlock *Node, const PGOUseFunc *Graph)
This provides a very simple, boring adaptor for a begin and end iterator into a range type...
bool canRenameComdatFunc(const Function &F, bool CheckAddressTaken=false)
Check if we can safely rename this Comdat function.
Definition: InstrProf.cpp:972
pgo instr gen
An efficient, type-erasing, non-owning reference to a callable.
Definition: STLExtras.h:93
INITIALIZE_PASS_BEGIN(PGOInstrumentationGenLegacyPass, "pgo-instr-gen", "PGO instrumentation.", false, false) INITIALIZE_PASS_END(PGOInstrumentationGenLegacyPass
This file contains the declaration of the Comdat class, which represents a single COMDAT in LLVM...
virtual std::string message() const
Return the error message as a string.
Definition: Error.h:55
Externally visible function.
Definition: GlobalValue.h:49
static cl::opt< bool > PGOInstrMemOP("pgo-instr-memop", cl::init(true), cl::Hidden, cl::desc("Use this option to turn on/off " "memory intrinsic size profiling."))
uint64_t getMaximumFunctionCount()
Return the maximum of all known function counts.
STATISTIC(NumFunctions, "Total number of functions")
F(f)
static IntegerType * getInt64Ty(LLVMContext &C)
Definition: Type.cpp:177
Value * getCondition() const
bool isVectorTy() const
True if this is an instance of VectorType.
Definition: Type.h:227
Error takeError()
Take ownership of the stored error.
Definition: Error.h:537
Value * getLength() const
Base class for error info classes.
Definition: Error.h:47
An union-find based Minimum Spanning Tree for CFG.
Definition: CFGMST.h:38
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE const char * data() const
data - Get a pointer to the start of the string (which may not be null terminated).
Definition: StringRef.h:128
Function::ProfileCount ProfileCount
iterator begin()
Instruction iterator methods.
Definition: BasicBlock.h:264
AnalysisUsage & addRequired()
#define INITIALIZE_PASS_DEPENDENCY(depName)
Definition: PassSupport.h:51
Definition: BitVector.h:921
This class represents the LLVM &#39;select&#39; instruction.
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
PGOInstrumentationUse(std::string Filename="")
IntegerType * getInt64Ty()
Fetch the type representing a 64-bit integer.
Definition: IRBuilder.h:352
LLVMContext & getContext() const
Get the global data context.
Definition: Module.h:242
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:731
This file contains the simple types necessary to represent the attributes associated with functions a...
Legacy analysis pass which computes BlockFrequencyInfo.
static std::string getGraphName(const PGOUseFunc *G)
VisitMode
The select instruction visitor plays three roles specified by the mode.
Tagged union holding either a T or a Error.
Definition: CachePruning.h:23
This file implements a class to represent arbitrary precision integral constant values and operations...
Interval::succ_iterator succ_begin(Interval *I)
succ_begin/succ_end - define methods so that Intervals may be used just like BasicBlocks can with the...
Definition: Interval.h:103
static bool isSimple(Instruction *I)
Analysis pass which computes BranchProbabilityInfo.
auto reverse(ContainerTy &&C, typename std::enable_if< has_rbegin< ContainerTy >::value >::type *=nullptr) -> decltype(make_range(C.rbegin(), C.rend()))
Definition: STLExtras.h:237
ValTy * getCalledValue() const
Return the pointer to function that is being called.
Definition: CallSite.h:100
bool isOne() const
This is just a convenience method to make client code smaller for a common case.
Definition: Constants.h:201
This file provides the interface for IR based instrumentation passes ( (profile-gen, and profile-use).
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
static cl::opt< bool > DisableValueProfiling("disable-vp", cl::init(false), cl::Hidden, cl::desc("Disable Value Profiling"))
static NodeRef getEntryNode(const PGOUseFunc *G)
static bool isIndirectBrTarget(BasicBlock *BB)
static void createIRLevelProfileFlagVariable(Module &M)
void setComdat(Comdat *C)
Definition: GlobalObject.h:103
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:133
static void setBranchWeights(SwitchInst *SI, ArrayRef< uint32_t > Weights)
raw_ostream & WriteGraph(raw_ostream &O, const GraphType &G, bool ShortNames=false, const Twine &Title="")
Definition: GraphWriter.h:309
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
void initializePGOInstrumentationGenLegacyPassPass(PassRegistry &)
static bool InstrumentAllFunctions(Module &M, function_ref< BranchProbabilityInfo *(Function &)> LookupBPI, function_ref< BlockFrequencyInfo *(Function &)> LookupBFI)
bool isMinusOne() const
This function will return true iff every bit in this constant is set to true.
Definition: Constants.h:209
static bool canRenameComdat(Function &F, std::unordered_multimap< Comdat *, GlobalValue *> &ComdatMembers)
Value * CreateZExt(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1556
static nodes_iterator nodes_end(const PGOUseFunc *G)
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree...
Definition: Dominators.h:142
amdgpu Simplify well known AMD library false Value * Callee
Function * getDeclaration(Module *M, ID id, ArrayRef< Type *> Tys=None)
Create or insert an LLVM Function declaration for an intrinsic, and return it.
Definition: Function.cpp:1001
instrprof_error get() const
Definition: InstrProf.h:320
Legacy analysis pass which computes BranchProbabilityInfo.
Value * getOperand(unsigned i) const
Definition: User.h:170
static PreservedAnalyses none()
Convenience factory function for the empty preserved set.
Definition: PassManager.h:156
static ChildIteratorType child_end(const NodeRef N)
Interval::succ_iterator succ_end(Interval *I)
Definition: Interval.h:106
static cl::opt< unsigned > MaxNumMemOPAnnotations("memop-max-annotations", cl::init(4), cl::Hidden, cl::ZeroOrMore, cl::desc("Max number of preicise value annotations for a single memop" "intrinsic"))
std::string message() const override
Return the error message as a string.
Definition: InstrProf.cpp:209
static Constant * getBitCast(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1740
BasicBlock * SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum, const CriticalEdgeSplittingOptions &Options=CriticalEdgeSplittingOptions())
If this edge is a critical edge, insert a new node to split the critical edge.
BlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation to estimate IR basic block frequen...
Same, but only replaced by something equivalent.
Definition: GlobalValue.h:52
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:410
StringRef getName() const
Definition: Comdat.cpp:27
Subclasses of this class are all able to terminate a basic block.
Definition: InstrTypes.h:55
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:153
const_iterator getFirstInsertionPt() const
Returns an iterator to the first instruction in this block that is suitable for inserting a non-PHI i...
Definition: BasicBlock.cpp:218
LLVM Basic Block Representation.
Definition: BasicBlock.h:59
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
Conditional or Unconditional Branch instruction.
#define DEBUG_TYPE
void setIrrLoopHeaderMetadata(Module *M, Instruction *TI, uint64_t Count)
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
ValuesClass values(OptsTy... Options)
Helper to build a ValuesClass by forwarding a variable number of arguments as an initializer list to ...
Definition: CommandLine.h:630
static StringRef getPredicateName(Predicate P)
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Diagnostic information for applied optimization remarks.
Interval::pred_iterator pred_begin(Interval *I)
pred_begin/pred_end - define methods so that Intervals may be used just like BasicBlocks can with the...
Definition: Interval.h:113
Represent the analysis usage information of a pass.
static cl::opt< PGOViewCountsType > PGOViewRawCounts("pgo-view-raw-counts", cl::Hidden, cl::desc("A boolean option to show CFG dag or text " "with raw profile counts from " "profile data. See also option " "-pgo-view-counts. To limit graph " "display to only one function, use " "filtering option -view-bfi-func-name."), cl::values(clEnumValN(PGOVCT_None, "none", "do not show."), clEnumValN(PGOVCT_Graph, "graph", "show a graph."), clEnumValN(PGOVCT_Text, "text", "show in text.")))
static cl::opt< bool > DoComdatRenaming("do-comdat-renaming", cl::init(false), cl::Hidden, cl::desc("Append function hash to the name of COMDAT function to avoid " "function hash mismatch due to the preinliner"))
ModulePass * createPGOInstrumentationUseLegacyPass(StringRef Filename=StringRef(""))
This instruction compares its operands according to the predicate given to the constructor.
static std::string getBranchCondString(Instruction *TI)
Interval::pred_iterator pred_end(Interval *I)
Definition: Interval.h:116
static uint64_t calculateCountScale(uint64_t MaxCount)
Calculate what to divide by to scale counts.
ConstantInt * getInt64(uint64_t C)
Get a constant 64-bit value.
Definition: IRBuilder.h:312
void ViewGraph(const GraphType &G, const Twine &Name, bool ShortNames=false, const Twine &Title="", GraphProgram::Name Program=GraphProgram::DOT)
ViewGraph - Emit a dot graph, run &#39;dot&#39;, run gv on the postscript file, then cleanup.
Definition: GraphWriter.h:348
static cl::opt< bool > NoPGOWarnMismatchComdat("no-pgo-warn-mismatch-comdat", cl::init(true), cl::Hidden, cl::desc("The option is used to turn on/off " "warnings about hash mismatch for comdat " "functions."))
void initializePGOInstrumentationUseLegacyPassPass(PassRegistry &)
DenseMap< const BasicBlock *, std::unique_ptr< BBInfo > > BBInfos
Definition: CFGMST.h:47
const Value * getCondition() const
static uint32_t scaleBranchCount(uint64_t Count, uint64_t Scale)
Scale an individual branch count.
Comdat * getOrInsertComdat(StringRef Name)
Return the Comdat in the module with the specified name.
Definition: Module.cpp:474
void annotateValueSite(Module &M, Instruction &Inst, const InstrProfRecord &InstrProfR, InstrProfValueKind ValueKind, uint32_t SiteIndx, uint32_t MaxMDCount=3)
Get the value profile data for value site SiteIdx from InstrProfR and annotate the instruction Inst w...
Definition: InstrProf.cpp:812
static PreservedAnalyses all()
Construct a special preserved set that preserves all passes.
Definition: PassManager.h:159
Class to represent profile counts.
Definition: Function.h:247
void createPGOFuncNameMetadata(Function &F, StringRef PGOFuncName)
Create the PGOFuncName meta data if PGOFuncName is different from function&#39;s raw name.
Definition: InstrProf.cpp:913
PointerType * getInt8PtrTy(unsigned AddrSpace=0)
Fetch the type representing a pointer to an 8-bit integer value.
Definition: IRBuilder.h:385
static PointerType * getInt8PtrTy(LLVMContext &C, unsigned AS=0)
Definition: Type.cpp:220
void printAsOperand(raw_ostream &O, bool PrintType=true, const Module *M=nullptr) const
Print the name of this Value out to the specified raw_ostream.
Definition: AsmWriter.cpp:4112
std::string & str()
Flushes the stream contents to the target string and returns the string&#39;s reference.
Definition: raw_ostream.h:493
INITIALIZE_PASS_END(RegBankSelect, DEBUG_TYPE, "Assign register bank of generic virtual registers", false, false) RegBankSelect
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void setMetadata(unsigned KindID, MDNode *Node)
Set the metadata of the specified kind to the specified node.
Definition: Metadata.cpp:1226
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:44
static Constant * getIntegerValue(Type *Ty, const APInt &V)
Return the value for an integer or pointer constant, or a vector thereof, with the given scalar value...
Definition: Constants.cpp:295
DOTGraphTraits - Template class that can be specialized to customize how graphs are converted to &#39;dot...
BBInfo * findBBInfo(const BasicBlock *BB) const
Definition: CFGMST.h:89
iterator_range< T > make_range(T x, T y)
Convenience function for iterating over sub-ranges.
void handleAllErrors(Error E, HandlerTs &&... Handlers)
Behaves the same as handleErrors, except that by contract all errors must be handled by the given han...
Definition: Error.h:889
Analysis pass which computes BlockFrequencyInfo.
This is the common base class for memset/memcpy/memmove.
This is the shared class of boolean and integer constants.
Definition: Constants.h:84
void setSelectionKind(SelectionKind Val)
Definition: Comdat.h:46
void emit(DiagnosticInfoOptimizationBase &OptDiag)
Output the remark via the diagnostic handler and to the optimization record file. ...
auto size(R &&Range, typename std::enable_if< std::is_same< typename std::iterator_traits< decltype(Range.begin())>::iterator_category, std::random_access_iterator_tag >::value, void >::type *=nullptr) -> decltype(std::distance(Range.begin(), Range.end()))
Get the size of a range.
Definition: STLExtras.h:1032
static nodes_iterator nodes_begin(const PGOUseFunc *G)
static cl::opt< bool > PGOInstrSelect("pgo-instr-select", cl::init(true), cl::Hidden, cl::desc("Use this option to turn on/off SELECT " "instruction instrumentation. "))
iterator end()
Definition: BasicBlock.h:266
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:861
Module.h This file contains the declarations for the Module class.
pgo instr PGO instrumentation
const DataFlowGraph & G
Definition: RDFGraph.cpp:211
PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM)
ConstantInt * getInt32(uint32_t C)
Get a constant 32-bit value.
Definition: IRBuilder.h:307
PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM)
uint64_t scale(uint64_t Num) const
Scale a large integer.
reference get()
Returns a reference to the stored T value.
Definition: Error.h:517
bool isConditional() const
void dumpEdges(raw_ostream &OS, const Twine &Message) const
Definition: CFGMST.h:236
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:133
Class for arbitrary precision integers.
Definition: APInt.h:69
static cl::opt< std::string > PGOTestProfileFile("pgo-test-profile-file", cl::init(""), cl::Hidden, cl::value_desc("filename"), cl::desc("Specify the path of profile data file. This is" "mainly for test purpose."))
BBInfo & getBBInfo(const BasicBlock *BB) const
Definition: CFGMST.h:82
#define clEnumValN(ENUMVAL, FLAGNAME, DESC)
Definition: CommandLine.h:605
const Comdat * getComdat() const
Definition: GlobalObject.h:101
pgo instr Read PGO instrumentation profile
Predicate getPredicate() const
Return the predicate for this instruction.
Definition: InstrTypes.h:959
Analysis providing branch probability information.
unsigned GetSuccessorNumber(const BasicBlock *BB, const BasicBlock *Succ)
Search for the specified successor of basic block BB and return its position in the terminator instru...
Definition: CFG.cpp:72
Profiling information for a single function.
Definition: InstrProf.h:622
Expected< InstrProfRecord > getInstrProfRecord(StringRef FuncName, uint64_t FuncHash)
Return the NamedInstrProfRecord associated with FuncName and FuncHash.
static bool annotateAllFunctions(Module &M, StringRef ProfileFileName, function_ref< BranchProbabilityInfo *(Function &)> LookupBPI, function_ref< BlockFrequencyInfo *(Function &)> LookupBFI)
void print(raw_ostream &O, bool IsForDebug=false, bool NoDetails=false) const
Print the current type.
Definition: AsmWriter.cpp:4009
std::string getPGOFuncName(const Function &F, bool InLTO=false, uint64_t Version=INSTR_PROF_INDEX_VERSION)
Return the modified name for function F suitable to be used the key for profile lookup.
Definition: InstrProf.cpp:253
bool SplitIndirectBrCriticalEdges(Function &F, BranchProbabilityInfo *BPI=nullptr, BlockFrequencyInfo *BFI=nullptr)
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:224
const Function * getParent() const
Return the enclosing method, or null if none.
Definition: BasicBlock.h:108
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
ModulePass class - This class is used to implement unstructured interprocedural optimizations and ana...
Definition: Pass.h:225
GlobalVariable * createPGOFuncNameVar(Function &F, StringRef PGOFuncName)
Create and return the global variable for function name used in PGO instrumentation.
Definition: InstrProf.cpp:331
bool isZero() const
This is just a convenience method to make client code smaller for a common code.
Definition: Constants.h:193
LLVM_NODISCARD std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type dyn_cast(const Y &Val)
Definition: Casting.h:323
Keep one copy of named function when linking (weak)
Definition: GlobalValue.h:53
static cl::opt< unsigned > MaxNumAnnotations("icp-max-annotations", cl::init(3), cl::Hidden, cl::ZeroOrMore, cl::desc("Max number of annotations for a single indirect " "call callsite"))
std::string str() const
Return the twine contents as a std::string.
Definition: Twine.cpp:18
std::vector< Instruction * > findIndirectCallSites(Function &F)
cl::opt< PGOViewCountsType > PGOViewCounts
Value * CreatePtrToInt(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1619
TerminatorInst::SuccIterator< const TerminatorInst *, const BasicBlock > succ_const_iterator
Definition: CFG.h:127
const unsigned Kind
static void instrumentOneFunc(Function &F, Module *M, BranchProbabilityInfo *BPI, BlockFrequencyInfo *BFI, std::unordered_multimap< Comdat *, GlobalValue *> &ComdatMembers)
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
unsigned getNumSuccessors() const
Return the number of successors that this terminator has.
A raw_ostream that writes to an std::string.
Definition: raw_ostream.h:477
LLVM Value Representation.
Definition: Value.h:73
static Expected< std::unique_ptr< IndexedInstrProfReader > > create(const Twine &Path)
Factory method to create an indexed reader.
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
void update(ArrayRef< char > Data)
Definition: JamCRC.cpp:92
Lightweight error class with error context and mandatory checking.
Definition: Error.h:156
BasicBlock::iterator GetInsertPoint() const
Definition: IRBuilder.h:122
DefaultDOTGraphTraits - This class provides the default implementations of all of the DOTGraphTraits ...
IRTranslator LLVM IR MI
cl::opt< std::string > ViewBlockFreqFuncName
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
Reader for the indexed binary instrprof format.
A container for analyses that lazily runs them and caches their results.
static void collectComdatMembers(Module &M, std::unordered_multimap< Comdat *, GlobalValue *> &ComdatMembers)
const TerminatorInst * getTerminator() const LLVM_READONLY
Returns the terminator instruction if the block is well formed or null if the block is not well forme...
Definition: BasicBlock.cpp:138
pgo instr use
This header defines various interfaces for pass management in LLVM.
static std::string getSimpleNodeName(const BasicBlock *Node)
static cl::opt< bool > EmitBranchProbability("pgo-emit-branch-prob", cl::init(false), cl::Hidden, cl::desc("When this option is on, the annotated " "branch probability will be emitted as " "optimization remarks: -{Rpass|" "pass-remarks}=pgo-instrumentation"))
#define LLVM_DEBUG(X)
Definition: Debug.h:119
The optimization diagnostic interface.
static GlobalAlias * create(Type *Ty, unsigned AddressSpace, LinkageTypes Linkage, const Twine &Name, Constant *Aliasee, Module *Parent)
If a parent module is specified, the alias is automatically inserted into the end of the specified mo...
Definition: Globals.cpp:418
const BasicBlock * getParent() const
Definition: Instruction.h:67
SelectionKind getSelectionKind() const
Definition: Comdat.h:45
CallInst * CreateCall(Value *Callee, ArrayRef< Value *> Args=None, const Twine &Name="", MDNode *FPMathTag=nullptr)
Definition: IRBuilder.h:1871
An analysis over an "outer" IR unit that provides access to an analysis manager over an "inner" IR un...
Definition: PassManager.h:946