llvm/tools/llvm-profgen/ProfiledBinary.h

   1 //===-- ProfiledBinary.h - Binary decoder -----------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_TOOLS_LLVM_PROFGEN_PROFILEDBINARY_H
  10 #define LLVM_TOOLS_LLVM_PROFGEN_PROFILEDBINARY_H
  11
  12 #include "CallContext.h"
  13 #include "ErrorHandling.h"
  14 #include "llvm/ADT/DenseMap.h"
  15 #include "llvm/ADT/StringRef.h"
  16 #include "llvm/ADT/StringSet.h"
  17 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
  18 #include "llvm/DebugInfo/Symbolize/Symbolize.h"
  19 #include "llvm/MC/MCAsmInfo.h"
  20 #include "llvm/MC/MCContext.h"
  21 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
  22 #include "llvm/MC/MCInst.h"
  23 #include "llvm/MC/MCInstPrinter.h"
  24 #include "llvm/MC/MCInstrAnalysis.h"
  25 #include "llvm/MC/MCInstrInfo.h"
  26 #include "llvm/MC/MCObjectFileInfo.h"
  27 #include "llvm/MC/MCPseudoProbe.h"
  28 #include "llvm/MC/MCRegisterInfo.h"
  29 #include "llvm/MC/MCSubtargetInfo.h"
  30 #include "llvm/MC/MCTargetOptions.h"
  31 #include "llvm/Object/ELFObjectFile.h"
  32 #include "llvm/ProfileData/SampleProf.h"
  33 #include "llvm/Support/CommandLine.h"
  34 #include "llvm/Support/Path.h"
  35 #include "llvm/Transforms/IPO/SampleContextTracker.h"
  36 #include <map>
  37 #include <set>
  38 #include <sstream>
  39 #include <string>
  40 #include <unordered_map>
  41 #include <unordered_set>
  42 #include <vector>
  43
  44 namespace llvm {
  45 extern cl::opt<bool> EnableCSPreInliner;
  46 extern cl::opt<bool> UseContextCostForPreInliner;
  47 } // namespace llvm
  48
  49 using namespace llvm;
  50 using namespace sampleprof;
  51 using namespace llvm::object;
  52
  53 namespace llvm {
  54 namespace sampleprof {
  55
  56 class ProfiledBinary;
  57 class MissingFrameInferrer;
  58
  59 struct InstructionPointer {
  60   const ProfiledBinary *Binary;
  61   // Address of the executable segment of the binary.
  62   uint64_t Address;
  63   // Index to the sorted code address array of the binary.
  64   uint64_t Index = 0;
  65   InstructionPointer(const ProfiledBinary *Binary, uint64_t Address,
  66                      bool RoundToNext = false);
  67   bool advance();
  68   bool backward();
  69   void update(uint64_t Addr);
  70 };
  71
  72 // The special frame addresses.
  73 enum SpecialFrameAddr {
  74   // Dummy root of frame trie.
  75   DummyRoot = 0,
  76   // Represent all the addresses outside of current binary.
  77   // This's also used to indicate the call stack should be truncated since this
  78   // isn't a real call context the compiler will see.
  79   ExternalAddr = 1,
  80 };
  81
  82 using RangesTy = std::vector<std::pair<uint64_t, uint64_t>>;
  83
  84 struct BinaryFunction {
  85   StringRef FuncName;
  86   // End of range is an exclusive bound.
  87   RangesTy Ranges;
  88
  89   uint64_t getFuncSize() {
  90     uint64_t Sum = 0;
  91     for (auto &R : Ranges) {
  92       Sum += R.second - R.first;
  93     }
  94     return Sum;
  95   }
  96 };
  97
  98 // Info about function range. A function can be split into multiple
  99 // non-continuous ranges, each range corresponds to one FuncRange.
 100 struct FuncRange {
 101   uint64_t StartAddress;
 102   // EndAddress is an exclusive bound.
 103   uint64_t EndAddress;
 104   // Function the range belongs to
 105   BinaryFunction *Func;
 106   // Whether the start address is the real entry of the function.
 107   bool IsFuncEntry = false;
 108
 109   StringRef getFuncName() { return Func->FuncName; }
 110 };
 111
 112 // PrologEpilog address tracker, used to filter out broken stack samples
 113 // Currently we use a heuristic size (two) to infer prolog and epilog
 114 // based on the start address and return address. In the future,
 115 // we will switch to Dwarf CFI based tracker
 116 struct PrologEpilogTracker {
 117   // A set of prolog and epilog addresses. Used by virtual unwinding.
 118   std::unordered_set<uint64_t> PrologEpilogSet;
 119   ProfiledBinary *Binary;
 120   PrologEpilogTracker(ProfiledBinary *Bin) : Binary(Bin){};
 121
 122   // Take the two addresses from the start of function as prolog
 123   void
 124   inferPrologAddresses(std::map<uint64_t, FuncRange> &FuncStartAddressMap) {
 125     for (auto I : FuncStartAddressMap) {
 126       PrologEpilogSet.insert(I.first);
 127       InstructionPointer IP(Binary, I.first);
 128       if (!IP.advance())
 129         break;
 130       PrologEpilogSet.insert(IP.Address);
 131     }
 132   }
 133
 134   // Take the last two addresses before the return address as epilog
 135   void inferEpilogAddresses(std::unordered_set<uint64_t> &RetAddrs) {
 136     for (auto Addr : RetAddrs) {
 137       PrologEpilogSet.insert(Addr);
 138       InstructionPointer IP(Binary, Addr);
 139       if (!IP.backward())
 140         break;
 141       PrologEpilogSet.insert(IP.Address);
 142     }
 143   }
 144 };
 145
 146 // Track function byte size under different context (outlined version as well as
 147 // various inlined versions). It also provides query support to get function
 148 // size with the best matching context, which is used to help pre-inliner use
 149 // accurate post-optimization size to make decisions.
 150 // TODO: If an inlinee is completely optimized away, ideally we should have zero
 151 // for its context size, currently we would misss such context since it doesn't
 152 // have instructions. To fix this, we need to mark all inlinee with entry probe
 153 // but without instructions as having zero size.
 154 class BinarySizeContextTracker {
 155 public:
 156   // Add instruction with given size to a context
 157   void addInstructionForContext(const SampleContextFrameVector &Context,
 158                                 uint32_t InstrSize);
 159
 160   // Get function size with a specific context. When there's no exact match
 161   // for the given context, try to retrieve the size of that function from
 162   // closest matching context.
 163   uint32_t getFuncSizeForContext(const ContextTrieNode *Context);
 164
 165   // For inlinees that are full optimized away, we can establish zero size using
 166   // their remaining probes.
 167   void trackInlineesOptimizedAway(MCPseudoProbeDecoder &ProbeDecoder);
 168
 169   using ProbeFrameStack = SmallVector<std::pair<StringRef, uint32_t>>;
 170   void trackInlineesOptimizedAway(MCPseudoProbeDecoder &ProbeDecoder,
 171                                   MCDecodedPseudoProbeInlineTree &ProbeNode,
 172                                   ProbeFrameStack &Context);
 173
 174   void dump() { RootContext.dumpTree(); }
 175
 176 private:
 177   // Root node for context trie tree, node that this is a reverse context trie
 178   // with callee as parent and caller as child. This way we can traverse from
 179   // root to find the best/longest matching context if an exact match does not
 180   // exist. It gives us the best possible estimate for function's post-inline,
 181   // post-optimization byte size.
 182   ContextTrieNode RootContext;
 183 };
 184
 185 using AddressRange = std::pair<uint64_t, uint64_t>;
 186
 187 class ProfiledBinary {
 188   // Absolute path of the executable binary.
 189   std::string Path;
 190   // Path of the debug info binary.
 191   std::string DebugBinaryPath;
 192   // The target triple.
 193   Triple TheTriple;
 194   // Path of symbolizer path which should be pointed to binary with debug info.
 195   StringRef SymbolizerPath;
 196   // Options used to configure the symbolizer
 197   symbolize::LLVMSymbolizer::Options SymbolizerOpts;
 198   // The runtime base address that the first executable segment is loaded at.
 199   uint64_t BaseAddress = 0;
 200   // The runtime base address that the first loadabe segment is loaded at.
 201   uint64_t FirstLoadableAddress = 0;
 202   // The preferred load address of each executable segment.
 203   std::vector<uint64_t> PreferredTextSegmentAddresses;
 204   // The file offset of each executable segment.
 205   std::vector<uint64_t> TextSegmentOffsets;
 206
 207   // Mutiple MC component info
 208   std::unique_ptr<const MCRegisterInfo> MRI;
 209   std::unique_ptr<const MCAsmInfo> AsmInfo;
 210   std::unique_ptr<const MCSubtargetInfo> STI;
 211   std::unique_ptr<const MCInstrInfo> MII;
 212   std::unique_ptr<MCDisassembler> DisAsm;
 213   std::unique_ptr<const MCInstrAnalysis> MIA;
 214   std::unique_ptr<MCInstPrinter> IPrinter;
 215   // A list of text sections sorted by start RVA and size. Used to check
 216   // if a given RVA is a valid code address.
 217   std::set<std::pair<uint64_t, uint64_t>> TextSections;
 218
 219   // A map of mapping function name to BinaryFunction info.
 220   std::unordered_map<std::string, BinaryFunction> BinaryFunctions;
 221
 222   // Lookup BinaryFunctions using the function name's MD5 hash. Needed if the
 223   // profile is using MD5.
 224   std::unordered_map<uint64_t, BinaryFunction *> HashBinaryFunctions;
 225
 226   // A list of binary functions that have samples.
 227   std::unordered_set<const BinaryFunction *> ProfiledFunctions;
 228
 229   // GUID to Elf symbol start address map
 230   DenseMap<uint64_t, uint64_t> SymbolStartAddrs;
 231
 232   // These maps are for temporary use of warning diagnosis.
 233   DenseSet<int64_t> AddrsWithMultipleSymbols;
 234   DenseSet<std::pair<uint64_t, uint64_t>> AddrsWithInvalidInstruction;
 235
 236   // Start address to Elf symbol GUID map
 237   std::unordered_multimap<uint64_t, uint64_t> StartAddrToSymMap;
 238
 239   // An ordered map of mapping function's start address to function range
 240   // relevant info. Currently to determine if the offset of ELF is the start of
 241   // a real function, we leverage the function range info from DWARF.
 242   std::map<uint64_t, FuncRange> StartAddrToFuncRangeMap;
 243
 244   // Address to context location map. Used to expand the context.
 245   std::unordered_map<uint64_t, SampleContextFrameVector> AddressToLocStackMap;
 246
 247   // Address to instruction size map. Also used for quick Address lookup.
 248   std::unordered_map<uint64_t, uint64_t> AddressToInstSizeMap;
 249
 250   // An array of Addresses of all instructions sorted in increasing order. The
 251   // sorting is needed to fast advance to the next forward/backward instruction.
 252   std::vector<uint64_t> CodeAddressVec;
 253   // A set of call instruction addresses. Used by virtual unwinding.
 254   std::unordered_set<uint64_t> CallAddressSet;
 255   // A set of return instruction addresses. Used by virtual unwinding.
 256   std::unordered_set<uint64_t> RetAddressSet;
 257   // An ordered set of unconditional branch instruction addresses.
 258   std::set<uint64_t> UncondBranchAddrSet;
 259   // A set of branch instruction addresses.
 260   std::unordered_set<uint64_t> BranchAddressSet;
 261
 262   // Estimate and track function prolog and epilog ranges.
 263   PrologEpilogTracker ProEpilogTracker;
 264
 265   // Infer missing frames due to compiler optimizations such as tail call
 266   // elimination.
 267   std::unique_ptr<MissingFrameInferrer> MissingContextInferrer;
 268
 269   // Track function sizes under different context
 270   BinarySizeContextTracker FuncSizeTracker;
 271
 272   // The symbolizer used to get inline context for an instruction.
 273   std::unique_ptr<symbolize::LLVMSymbolizer> Symbolizer;
 274
 275   // String table owning function name strings created from the symbolizer.
 276   std::unordered_set<std::string> NameStrings;
 277
 278   // A collection of functions to print disassembly for.
 279   StringSet<> DisassembleFunctionSet;
 280
 281   // Pseudo probe decoder
 282   MCPseudoProbeDecoder ProbeDecoder;
 283
 284   // Function name to probe frame map for top-level outlined functions.
 285   StringMap<MCDecodedPseudoProbeInlineTree *> TopLevelProbeFrameMap;
 286
 287   bool UsePseudoProbes = false;
 288
 289   bool UseFSDiscriminator = false;
 290
 291   // Whether we need to symbolize all instructions to get function context size.
 292   bool TrackFuncContextSize = false;
 293
 294   // Indicate if the base loading address is parsed from the mmap event or uses
 295   // the preferred address
 296   bool IsLoadedByMMap = false;
 297   // Use to avoid redundant warning.
 298   bool MissingMMapWarned = false;
 299
 300   void setPreferredTextSegmentAddresses(const ELFObjectFileBase *O);
 301
 302   template <class ELFT>
 303   void setPreferredTextSegmentAddresses(const ELFFile<ELFT> &Obj,
 304                                         StringRef FileName);
 305
 306   void checkPseudoProbe(const ELFObjectFileBase *Obj);
 307
 308   void decodePseudoProbe(const ELFObjectFileBase *Obj);
 309
 310   void
 311   checkUseFSDiscriminator(const ELFObjectFileBase *Obj,
 312                           std::map<SectionRef, SectionSymbolsTy> &AllSymbols);
 313
 314   // Set up disassembler and related components.
 315   void setUpDisassembler(const ELFObjectFileBase *Obj);
 316   symbolize::LLVMSymbolizer::Options getSymbolizerOpts() const;
 317
 318   // Load debug info of subprograms from DWARF section.
 319   void loadSymbolsFromDWARF(ObjectFile &Obj);
 320
 321   // Load debug info from DWARF unit.
 322   void loadSymbolsFromDWARFUnit(DWARFUnit &CompilationUnit);
 323
 324   // Create elf symbol to its start address mapping.
 325   void populateElfSymbolAddressList(const ELFObjectFileBase *O);
 326
 327   // A function may be spilt into multiple non-continuous address ranges. We use
 328   // this to set whether start a function range is the real entry of the
 329   // function and also set false to the non-function label.
 330   void setIsFuncEntry(FuncRange *FRange, StringRef RangeSymName);
 331
 332   // Warn if no entry range exists in the function.
 333   void warnNoFuncEntry();
 334
 335   /// Dissassemble the text section and build various address maps.
 336   void disassemble(const ELFObjectFileBase *O);
 337
 338   /// Helper function to dissassemble the symbol and extract info for unwinding
 339   bool dissassembleSymbol(std::size_t SI, ArrayRef<uint8_t> Bytes,
 340                           SectionSymbolsTy &Symbols, const SectionRef &Section);
 341   /// Symbolize a given instruction pointer and return a full call context.
 342   SampleContextFrameVector symbolize(const InstructionPointer &IP,
 343                                      bool UseCanonicalFnName = false,
 344                                      bool UseProbeDiscriminator = false);
 345   /// Decode the interesting parts of the binary and build internal data
 346   /// structures. On high level, the parts of interest are:
 347   ///   1. Text sections, including the main code section and the PLT
 348   ///   entries that will be used to handle cross-module call transitions.
 349   ///   2. The .debug_line section, used by Dwarf-based profile generation.
 350   ///   3. Pseudo probe related sections, used by probe-based profile
 351   ///   generation.
 352   void load();
 353
 354 public:
 355   ProfiledBinary(const StringRef ExeBinPath, const StringRef DebugBinPath);
 356   ~ProfiledBinary();
 357
 358   void decodePseudoProbe();
 359
 360   StringRef getPath() const { return Path; }
 361   StringRef getName() const { return llvm::sys::path::filename(Path); }
 362   uint64_t getBaseAddress() const { return BaseAddress; }
 363   void setBaseAddress(uint64_t Address) { BaseAddress = Address; }
 364
 365   // Canonicalize to use preferred load address as base address.
 366   uint64_t canonicalizeVirtualAddress(uint64_t Address) {
 367     return Address - BaseAddress + getPreferredBaseAddress();
 368   }
 369   // Return the preferred load address for the first executable segment.
 370   uint64_t getPreferredBaseAddress() const {
 371     return PreferredTextSegmentAddresses[0];
 372   }
 373   // Return the preferred load address for the first loadable segment.
 374   uint64_t getFirstLoadableAddress() const { return FirstLoadableAddress; }
 375   // Return the file offset for the first executable segment.
 376   uint64_t getTextSegmentOffset() const { return TextSegmentOffsets[0]; }
 377   const std::vector<uint64_t> &getPreferredTextSegmentAddresses() const {
 378     return PreferredTextSegmentAddresses;
 379   }
 380   const std::vector<uint64_t> &getTextSegmentOffsets() const {
 381     return TextSegmentOffsets;
 382   }
 383
 384   uint64_t getInstSize(uint64_t Address) const {
 385     auto I = AddressToInstSizeMap.find(Address);
 386     if (I == AddressToInstSizeMap.end())
 387       return 0;
 388     return I->second;
 389   }
 390
 391   bool addressIsCode(uint64_t Address) const {
 392     return AddressToInstSizeMap.find(Address) != AddressToInstSizeMap.end();
 393   }
 394
 395   bool addressIsCall(uint64_t Address) const {
 396     return CallAddressSet.count(Address);
 397   }
 398   bool addressIsReturn(uint64_t Address) const {
 399     return RetAddressSet.count(Address);
 400   }
 401   bool addressInPrologEpilog(uint64_t Address) const {
 402     return ProEpilogTracker.PrologEpilogSet.count(Address);
 403   }
 404
 405   bool addressIsTransfer(uint64_t Address) {
 406     return BranchAddressSet.count(Address) || RetAddressSet.count(Address) ||
 407            CallAddressSet.count(Address);
 408   }
 409
 410   bool rangeCrossUncondBranch(uint64_t Start, uint64_t End) {
 411     if (Start >= End)
 412       return false;
 413     auto R = UncondBranchAddrSet.lower_bound(Start);
 414     return R != UncondBranchAddrSet.end() && *R < End;
 415   }
 416
 417   uint64_t getAddressforIndex(uint64_t Index) const {
 418     return CodeAddressVec[Index];
 419   }
 420
 421   size_t getCodeAddrVecSize() const { return CodeAddressVec.size(); }
 422
 423   bool usePseudoProbes() const { return UsePseudoProbes; }
 424   bool useFSDiscriminator() const { return UseFSDiscriminator; }
 425   // Get the index in CodeAddressVec for the address
 426   // As we might get an address which is not the code
 427   // here it would round to the next valid code address by
 428   // using lower bound operation
 429   uint32_t getIndexForAddr(uint64_t Address) const {
 430     auto Low = llvm::lower_bound(CodeAddressVec, Address);
 431     return Low - CodeAddressVec.begin();
 432   }
 433
 434   uint64_t getCallAddrFromFrameAddr(uint64_t FrameAddr) const {
 435     if (FrameAddr == ExternalAddr)
 436       return ExternalAddr;
 437     auto I = getIndexForAddr(FrameAddr);
 438     FrameAddr = I ? getAddressforIndex(I - 1) : 0;
 439     if (FrameAddr && addressIsCall(FrameAddr))
 440       return FrameAddr;
 441     return 0;
 442   }
 443
 444   FuncRange *findFuncRangeForStartAddr(uint64_t Address) {
 445     auto I = StartAddrToFuncRangeMap.find(Address);
 446     if (I == StartAddrToFuncRangeMap.end())
 447       return nullptr;
 448     return &I->second;
 449   }
 450
 451   // Binary search the function range which includes the input address.
 452   FuncRange *findFuncRange(uint64_t Address) {
 453     auto I = StartAddrToFuncRangeMap.upper_bound(Address);
 454     if (I == StartAddrToFuncRangeMap.begin())
 455       return nullptr;
 456     I--;
 457
 458     if (Address >= I->second.EndAddress)
 459       return nullptr;
 460
 461     return &I->second;
 462   }
 463
 464   // Get all ranges of one function.
 465   RangesTy getRanges(uint64_t Address) {
 466     auto *FRange = findFuncRange(Address);
 467     // Ignore the range which falls into plt section or system lib.
 468     if (!FRange)
 469       return RangesTy();
 470
 471     return FRange->Func->Ranges;
 472   }
 473
 474   const std::unordered_map<std::string, BinaryFunction> &
 475   getAllBinaryFunctions() {
 476     return BinaryFunctions;
 477   }
 478
 479   std::unordered_set<const BinaryFunction *> &getProfiledFunctions() {
 480     return ProfiledFunctions;
 481   }
 482
 483   void setProfiledFunctions(std::unordered_set<const BinaryFunction *> &Funcs) {
 484     ProfiledFunctions = Funcs;
 485   }
 486
 487   BinaryFunction *getBinaryFunction(FunctionId FName) {
 488     if (FName.isStringRef()) {
 489       auto I = BinaryFunctions.find(FName.str());
 490       if (I == BinaryFunctions.end())
 491         return nullptr;
 492       return &I->second;
 493     }
 494     auto I = HashBinaryFunctions.find(FName.getHashCode());
 495     if (I == HashBinaryFunctions.end())
 496       return nullptr;
 497     return I->second;
 498   }
 499
 500   uint32_t getFuncSizeForContext(const ContextTrieNode *ContextNode) {
 501     return FuncSizeTracker.getFuncSizeForContext(ContextNode);
 502   }
 503
 504   void inferMissingFrames(const SmallVectorImpl<uint64_t> &Context,
 505                           SmallVectorImpl<uint64_t> &NewContext);
 506
 507   // Load the symbols from debug table and populate into symbol list.
 508   void populateSymbolListFromDWARF(ProfileSymbolList &SymbolList);
 509
 510   SampleContextFrameVector
 511   getFrameLocationStack(uint64_t Address, bool UseProbeDiscriminator = false) {
 512     InstructionPointer IP(this, Address);
 513     return symbolize(IP, SymbolizerOpts.UseSymbolTable, UseProbeDiscriminator);
 514   }
 515
 516   const SampleContextFrameVector &
 517   getCachedFrameLocationStack(uint64_t Address,
 518                               bool UseProbeDiscriminator = false) {
 519     auto I = AddressToLocStackMap.emplace(Address, SampleContextFrameVector());
 520     if (I.second) {
 521       I.first->second = getFrameLocationStack(Address, UseProbeDiscriminator);
 522     }
 523     return I.first->second;
 524   }
 525
 526   std::optional<SampleContextFrame> getInlineLeafFrameLoc(uint64_t Address) {
 527     const auto &Stack = getCachedFrameLocationStack(Address);
 528     if (Stack.empty())
 529       return {};
 530     return Stack.back();
 531   }
 532
 533   void flushSymbolizer() { Symbolizer.reset(); }
 534
 535   MissingFrameInferrer *getMissingContextInferrer() {
 536     return MissingContextInferrer.get();
 537   }
 538
 539   // Compare two addresses' inline context
 540   bool inlineContextEqual(uint64_t Add1, uint64_t Add2);
 541
 542   // Get the full context of the current stack with inline context filled in.
 543   // It will search the disassembling info stored in AddressToLocStackMap. This
 544   // is used as the key of function sample map
 545   SampleContextFrameVector
 546   getExpandedContext(const SmallVectorImpl<uint64_t> &Stack,
 547                      bool &WasLeafInlined);
 548   // Go through instructions among the given range and record its size for the
 549   // inline context.
 550   void computeInlinedContextSizeForRange(uint64_t StartAddress,
 551                                          uint64_t EndAddress);
 552
 553   void computeInlinedContextSizeForFunc(const BinaryFunction *Func);
 554
 555   const MCDecodedPseudoProbe *getCallProbeForAddr(uint64_t Address) const {
 556     return ProbeDecoder.getCallProbeForAddr(Address);
 557   }
 558
 559   void getInlineContextForProbe(const MCDecodedPseudoProbe *Probe,
 560                                 SampleContextFrameVector &InlineContextStack,
 561                                 bool IncludeLeaf = false) const {
 562     SmallVector<MCPseduoProbeFrameLocation, 16> ProbeInlineContext;
 563     ProbeDecoder.getInlineContextForProbe(Probe, ProbeInlineContext,
 564                                           IncludeLeaf);
 565     for (uint32_t I = 0; I < ProbeInlineContext.size(); I++) {
 566       auto &Callsite = ProbeInlineContext[I];
 567       // Clear the current context for an unknown probe.
 568       if (Callsite.second == 0 && I != ProbeInlineContext.size() - 1) {
 569         InlineContextStack.clear();
 570         continue;
 571       }
 572       InlineContextStack.emplace_back(FunctionId(Callsite.first),
 573                                       LineLocation(Callsite.second, 0));
 574     }
 575   }
 576   const AddressProbesMap &getAddress2ProbesMap() const {
 577     return ProbeDecoder.getAddress2ProbesMap();
 578   }
 579   const MCPseudoProbeFuncDesc *getFuncDescForGUID(uint64_t GUID) {
 580     return ProbeDecoder.getFuncDescForGUID(GUID);
 581   }
 582
 583   const MCPseudoProbeFuncDesc *
 584   getInlinerDescForProbe(const MCDecodedPseudoProbe *Probe) {
 585     return ProbeDecoder.getInlinerDescForProbe(Probe);
 586   }
 587
 588   bool getTrackFuncContextSize() { return TrackFuncContextSize; }
 589
 590   bool getIsLoadedByMMap() { return IsLoadedByMMap; }
 591
 592   void setIsLoadedByMMap(bool Value) { IsLoadedByMMap = Value; }
 593
 594   bool getMissingMMapWarned() { return MissingMMapWarned; }
 595
 596   void setMissingMMapWarned(bool Value) { MissingMMapWarned = Value; }
 597 };
 598
 599 } // end namespace sampleprof
 600 } // end namespace llvm
 601
 602 #endif