1 //===- InstrProf.h - Instrumented profiling format support ------*- C++ -*-===//
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 // Instrumentation-based profiling data is generated by instrumented
11 // binaries through library functions in compiler-rt, and read by the clang
12 // frontend to feed PGO.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_PROFILEDATA_INSTRPROF_H
17 #define LLVM_PROFILEDATA_INSTRPROF_H
18 
19 #include "llvm/ADT/ArrayRef.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/ADT/StringSet.h"
23 #include "llvm/ADT/Triple.h"
24 #include "llvm/IR/GlobalValue.h"
25 #include "llvm/IR/ProfileSummary.h"
26 #include "llvm/ProfileData/InstrProfData.inc"
27 #include "llvm/Support/Compiler.h"
28 #include "llvm/Support/Endian.h"
29 #include "llvm/Support/Error.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/Host.h"
32 #include "llvm/Support/MD5.h"
33 #include "llvm/Support/MathExtras.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include <algorithm>
36 #include <cassert>
37 #include <cstddef>
38 #include <cstdint>
39 #include <cstring>
40 #include <list>
41 #include <memory>
42 #include <string>
43 #include <system_error>
44 #include <utility>
45 #include <vector>
46 
47 namespace llvm {
48 
49 class Function;
50 class GlobalVariable;
51 struct InstrProfRecord;
52 class InstrProfSymtab;
53 class Instruction;
54 class MDNode;
55 class Module;
56 
57 enum InstrProfSectKind {
58 #define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) Kind,
59 #include "llvm/ProfileData/InstrProfData.inc"
60 };
61 
62 /// Return the name of the profile section corresponding to \p IPSK.
63 ///
64 /// The name of the section depends on the object format type \p OF. If
65 /// \p AddSegmentInfo is true, a segment prefix and additional linker hints may
66 /// be added to the section name (this is the default).
67 std::string getInstrProfSectionName(InstrProfSectKind IPSK,
68                                     Triple::ObjectFormatType OF,
69                                     bool AddSegmentInfo = true);
70 
71 /// Return the name profile runtime entry point to do value profiling
72 /// for a given site.
getInstrProfValueProfFuncName()73 inline StringRef getInstrProfValueProfFuncName() {
74   return INSTR_PROF_VALUE_PROF_FUNC_STR;
75 }
76 
77 /// Return the name profile runtime entry point to do value range profiling.
getInstrProfValueRangeProfFuncName()78 inline StringRef getInstrProfValueRangeProfFuncName() {
79   return INSTR_PROF_VALUE_RANGE_PROF_FUNC_STR;
80 }
81 
82 /// Return the name prefix of variables containing instrumented function names.
getInstrProfNameVarPrefix()83 inline StringRef getInstrProfNameVarPrefix() { return "__profn_"; }
84 
85 /// Return the name prefix of variables containing per-function control data.
getInstrProfDataVarPrefix()86 inline StringRef getInstrProfDataVarPrefix() { return "__profd_"; }
87 
88 /// Return the name prefix of profile counter variables.
getInstrProfCountersVarPrefix()89 inline StringRef getInstrProfCountersVarPrefix() { return "__profc_"; }
90 
91 /// Return the name prefix of value profile variables.
getInstrProfValuesVarPrefix()92 inline StringRef getInstrProfValuesVarPrefix() { return "__profvp_"; }
93 
94 /// Return the name of value profile node array variables:
getInstrProfVNodesVarName()95 inline StringRef getInstrProfVNodesVarName() { return "__llvm_prf_vnodes"; }
96 
97 /// Return the name prefix of the COMDAT group for instrumentation variables
98 /// associated with a COMDAT function.
getInstrProfComdatPrefix()99 inline StringRef getInstrProfComdatPrefix() { return "__profv_"; }
100 
101 /// Return the name of the variable holding the strings (possibly compressed)
102 /// of all function's PGO names.
getInstrProfNamesVarName()103 inline StringRef getInstrProfNamesVarName() {
104   return "__llvm_prf_nm";
105 }
106 
107 /// Return the name of a covarage mapping variable (internal linkage)
108 /// for each instrumented source module. Such variables are allocated
109 /// in the __llvm_covmap section.
getCoverageMappingVarName()110 inline StringRef getCoverageMappingVarName() {
111   return "__llvm_coverage_mapping";
112 }
113 
114 /// Return the name of the internal variable recording the array
115 /// of PGO name vars referenced by the coverage mapping. The owning
116 /// functions of those names are not emitted by FE (e.g, unused inline
117 /// functions.)
getCoverageUnusedNamesVarName()118 inline StringRef getCoverageUnusedNamesVarName() {
119   return "__llvm_coverage_names";
120 }
121 
122 /// Return the name of function that registers all the per-function control
123 /// data at program startup time by calling __llvm_register_function. This
124 /// function has internal linkage and is called by  __llvm_profile_init
125 /// runtime method. This function is not generated for these platforms:
126 /// Darwin, Linux, and FreeBSD.
getInstrProfRegFuncsName()127 inline StringRef getInstrProfRegFuncsName() {
128   return "__llvm_profile_register_functions";
129 }
130 
131 /// Return the name of the runtime interface that registers per-function control
132 /// data for one instrumented function.
getInstrProfRegFuncName()133 inline StringRef getInstrProfRegFuncName() {
134   return "__llvm_profile_register_function";
135 }
136 
137 /// Return the name of the runtime interface that registers the PGO name strings.
getInstrProfNamesRegFuncName()138 inline StringRef getInstrProfNamesRegFuncName() {
139   return "__llvm_profile_register_names_function";
140 }
141 
142 /// Return the name of the runtime initialization method that is generated by
143 /// the compiler. The function calls __llvm_profile_register_functions and
144 /// __llvm_profile_override_default_filename functions if needed. This function
145 /// has internal linkage and invoked at startup time via init_array.
getInstrProfInitFuncName()146 inline StringRef getInstrProfInitFuncName() { return "__llvm_profile_init"; }
147 
148 /// Return the name of the hook variable defined in profile runtime library.
149 /// A reference to the variable causes the linker to link in the runtime
150 /// initialization module (which defines the hook variable).
getInstrProfRuntimeHookVarName()151 inline StringRef getInstrProfRuntimeHookVarName() {
152   return INSTR_PROF_QUOTE(INSTR_PROF_PROFILE_RUNTIME_VAR);
153 }
154 
155 /// Return the name of the compiler generated function that references the
156 /// runtime hook variable. The function is a weak global.
getInstrProfRuntimeHookVarUseFuncName()157 inline StringRef getInstrProfRuntimeHookVarUseFuncName() {
158   return "__llvm_profile_runtime_user";
159 }
160 
161 /// Return the marker used to separate PGO names during serialization.
getInstrProfNameSeparator()162 inline StringRef getInstrProfNameSeparator() { return "\01"; }
163 
164 /// Return the modified name for function \c F suitable to be
165 /// used the key for profile lookup. Variable \c InLTO indicates if this
166 /// is called in LTO optimization passes.
167 std::string getPGOFuncName(const Function &F, bool InLTO = false,
168                            uint64_t Version = INSTR_PROF_INDEX_VERSION);
169 
170 /// Return the modified name for a function suitable to be
171 /// used the key for profile lookup. The function's original
172 /// name is \c RawFuncName and has linkage of type \c Linkage.
173 /// The function is defined in module \c FileName.
174 std::string getPGOFuncName(StringRef RawFuncName,
175                            GlobalValue::LinkageTypes Linkage,
176                            StringRef FileName,
177                            uint64_t Version = INSTR_PROF_INDEX_VERSION);
178 
179 /// Return the name of the global variable used to store a function
180 /// name in PGO instrumentation. \c FuncName is the name of the function
181 /// returned by the \c getPGOFuncName call.
182 std::string getPGOFuncNameVarName(StringRef FuncName,
183                                   GlobalValue::LinkageTypes Linkage);
184 
185 /// Create and return the global variable for function name used in PGO
186 /// instrumentation. \c FuncName is the name of the function returned
187 /// by \c getPGOFuncName call.
188 GlobalVariable *createPGOFuncNameVar(Function &F, StringRef PGOFuncName);
189 
190 /// Create and return the global variable for function name used in PGO
191 /// instrumentation.  /// \c FuncName is the name of the function
192 /// returned by \c getPGOFuncName call, \c M is the owning module,
193 /// and \c Linkage is the linkage of the instrumented function.
194 GlobalVariable *createPGOFuncNameVar(Module &M,
195                                      GlobalValue::LinkageTypes Linkage,
196                                      StringRef PGOFuncName);
197 
198 /// Return the initializer in string of the PGO name var \c NameVar.
199 StringRef getPGOFuncNameVarInitializer(GlobalVariable *NameVar);
200 
201 /// Given a PGO function name, remove the filename prefix and return
202 /// the original (static) function name.
203 StringRef getFuncNameWithoutPrefix(StringRef PGOFuncName,
204                                    StringRef FileName = "<unknown>");
205 
206 /// Given a vector of strings (function PGO names) \c NameStrs, the
207 /// method generates a combined string \c Result thatis ready to be
208 /// serialized.  The \c Result string is comprised of three fields:
209 /// The first field is the legnth of the uncompressed strings, and the
210 /// the second field is the length of the zlib-compressed string.
211 /// Both fields are encoded in ULEB128.  If \c doCompress is false, the
212 ///  third field is the uncompressed strings; otherwise it is the
213 /// compressed string. When the string compression is off, the
214 /// second field will have value zero.
215 Error collectPGOFuncNameStrings(ArrayRef<std::string> NameStrs,
216                                 bool doCompression, std::string &Result);
217 
218 /// Produce \c Result string with the same format described above. The input
219 /// is vector of PGO function name variables that are referenced.
220 Error collectPGOFuncNameStrings(ArrayRef<GlobalVariable *> NameVars,
221                                 std::string &Result, bool doCompression = true);
222 
223 /// \c NameStrings is a string composed of one of more sub-strings encoded in
224 /// the format described above. The substrings are separated by 0 or more zero
225 /// bytes. This method decodes the string and populates the \c Symtab.
226 Error readPGOFuncNameStrings(StringRef NameStrings, InstrProfSymtab &Symtab);
227 
228 /// Check if INSTR_PROF_RAW_VERSION_VAR is defined. This global is only being
229 /// set in IR PGO compilation.
230 bool isIRPGOFlagSet(const Module *M);
231 
232 /// Check if we can safely rename this Comdat function. Instances of the same
233 /// comdat function may have different control flows thus can not share the
234 /// same counter variable.
235 bool canRenameComdatFunc(const Function &F, bool CheckAddressTaken = false);
236 
237 enum InstrProfValueKind : uint32_t {
238 #define VALUE_PROF_KIND(Enumerator, Value) Enumerator = Value,
239 #include "llvm/ProfileData/InstrProfData.inc"
240 };
241 
242 /// Get the value profile data for value site \p SiteIdx from \p InstrProfR
243 /// and annotate the instruction \p Inst with the value profile meta data.
244 /// Annotate up to \p MaxMDCount (default 3) number of records per value site.
245 void annotateValueSite(Module &M, Instruction &Inst,
246                        const InstrProfRecord &InstrProfR,
247                        InstrProfValueKind ValueKind, uint32_t SiteIndx,
248                        uint32_t MaxMDCount = 3);
249 
250 /// Same as the above interface but using an ArrayRef, as well as \p Sum.
251 void annotateValueSite(Module &M, Instruction &Inst,
252                        ArrayRef<InstrProfValueData> VDs, uint64_t Sum,
253                        InstrProfValueKind ValueKind, uint32_t MaxMDCount);
254 
255 /// Extract the value profile data from \p Inst which is annotated with
256 /// value profile meta data. Return false if there is no value data annotated,
257 /// otherwise  return true.
258 bool getValueProfDataFromInst(const Instruction &Inst,
259                               InstrProfValueKind ValueKind,
260                               uint32_t MaxNumValueData,
261                               InstrProfValueData ValueData[],
262                               uint32_t &ActualNumValueData, uint64_t &TotalC);
263 
getPGOFuncNameMetadataName()264 inline StringRef getPGOFuncNameMetadataName() { return "PGOFuncName"; }
265 
266 /// Return the PGOFuncName meta data associated with a function.
267 MDNode *getPGOFuncNameMetadata(const Function &F);
268 
269 /// Create the PGOFuncName meta data if PGOFuncName is different from
270 /// function's raw name. This should only apply to internal linkage functions
271 /// declared by users only.
272 void createPGOFuncNameMetadata(Function &F, StringRef PGOFuncName);
273 
274 /// Check if we can use Comdat for profile variables. This will eliminate
275 /// the duplicated profile variables for Comdat functions.
276 bool needsComdatForCounter(const Function &F, const Module &M);
277 
278 const std::error_category &instrprof_category();
279 
280 enum class instrprof_error {
281   success = 0,
282   eof,
283   unrecognized_format,
284   bad_magic,
285   bad_header,
286   unsupported_version,
287   unsupported_hash_type,
288   too_large,
289   truncated,
290   malformed,
291   unknown_function,
292   hash_mismatch,
293   count_mismatch,
294   counter_overflow,
295   value_site_count_mismatch,
296   compress_failed,
297   uncompress_failed,
298   empty_raw_profile,
299   zlib_unavailable
300 };
301 
make_error_code(instrprof_error E)302 inline std::error_code make_error_code(instrprof_error E) {
303   return std::error_code(static_cast<int>(E), instrprof_category());
304 }
305 
306 class InstrProfError : public ErrorInfo<InstrProfError> {
307 public:
InstrProfError(instrprof_error Err)308   InstrProfError(instrprof_error Err) : Err(Err) {
309     assert(Err != instrprof_error::success && "Not an error");
310   }
311 
312   std::string message() const override;
313 
log(raw_ostream & OS)314   void log(raw_ostream &OS) const override { OS << message(); }
315 
convertToErrorCode()316   std::error_code convertToErrorCode() const override {
317     return make_error_code(Err);
318   }
319 
get()320   instrprof_error get() const { return Err; }
321 
322   /// Consume an Error and return the raw enum value contained within it. The
323   /// Error must either be a success value, or contain a single InstrProfError.
take(Error E)324   static instrprof_error take(Error E) {
325     auto Err = instrprof_error::success;
326     handleAllErrors(std::move(E), [&Err](const InstrProfError &IPE) {
327       assert(Err == instrprof_error::success && "Multiple errors encountered");
328       Err = IPE.get();
329     });
330     return Err;
331   }
332 
333   static char ID;
334 
335 private:
336   instrprof_error Err;
337 };
338 
339 class SoftInstrProfErrors {
340   /// Count the number of soft instrprof_errors encountered and keep track of
341   /// the first such error for reporting purposes.
342 
343   /// The first soft error encountered.
344   instrprof_error FirstError = instrprof_error::success;
345 
346   /// The number of hash mismatches.
347   unsigned NumHashMismatches = 0;
348 
349   /// The number of count mismatches.
350   unsigned NumCountMismatches = 0;
351 
352   /// The number of counter overflows.
353   unsigned NumCounterOverflows = 0;
354 
355   /// The number of value site count mismatches.
356   unsigned NumValueSiteCountMismatches = 0;
357 
358 public:
359   SoftInstrProfErrors() = default;
360 
~SoftInstrProfErrors()361   ~SoftInstrProfErrors() {
362     assert(FirstError == instrprof_error::success &&
363            "Unchecked soft error encountered");
364   }
365 
366   /// Track a soft error (\p IE) and increment its associated counter.
367   void addError(instrprof_error IE);
368 
369   /// Get the number of hash mismatches.
getNumHashMismatches()370   unsigned getNumHashMismatches() const { return NumHashMismatches; }
371 
372   /// Get the number of count mismatches.
getNumCountMismatches()373   unsigned getNumCountMismatches() const { return NumCountMismatches; }
374 
375   /// Get the number of counter overflows.
getNumCounterOverflows()376   unsigned getNumCounterOverflows() const { return NumCounterOverflows; }
377 
378   /// Get the number of value site count mismatches.
getNumValueSiteCountMismatches()379   unsigned getNumValueSiteCountMismatches() const {
380     return NumValueSiteCountMismatches;
381   }
382 
383   /// Return the first encountered error and reset FirstError to a success
384   /// value.
takeError()385   Error takeError() {
386     if (FirstError == instrprof_error::success)
387       return Error::success();
388     auto E = make_error<InstrProfError>(FirstError);
389     FirstError = instrprof_error::success;
390     return E;
391   }
392 };
393 
394 namespace object {
395 
396 class SectionRef;
397 
398 } // end namespace object
399 
400 namespace IndexedInstrProf {
401 
402 uint64_t ComputeHash(StringRef K);
403 
404 } // end namespace IndexedInstrProf
405 
406 /// A symbol table used for function PGO name look-up with keys
407 /// (such as pointers, md5hash values) to the function. A function's
408 /// PGO name or name's md5hash are used in retrieving the profile
409 /// data of the function. See \c getPGOFuncName() method for details
410 /// on how PGO name is formed.
411 class InstrProfSymtab {
412 public:
413   using AddrHashMap = std::vector<std::pair<uint64_t, uint64_t>>;
414 
415 private:
416   StringRef Data;
417   uint64_t Address = 0;
418   // Unique name strings.
419   StringSet<> NameTab;
420   // A map from MD5 keys to function name strings.
421   std::vector<std::pair<uint64_t, StringRef>> MD5NameMap;
422   // A map from MD5 keys to function define. We only populate this map
423   // when build the Symtab from a Module.
424   std::vector<std::pair<uint64_t, Function *>> MD5FuncMap;
425   // A map from function runtime address to function name MD5 hash.
426   // This map is only populated and used by raw instr profile reader.
427   AddrHashMap AddrToMD5Map;
428   bool Sorted = false;
429 
getExternalSymbol()430   static StringRef getExternalSymbol() {
431     return "** External Symbol **";
432   }
433 
434   // If the symtab is created by a series of calls to \c addFuncName, \c
435   // finalizeSymtab needs to be called before looking up function names.
436   // This is required because the underlying map is a vector (for space
437   // efficiency) which needs to be sorted.
438   inline void finalizeSymtab();
439 
440 public:
441   InstrProfSymtab() = default;
442 
443   /// Create InstrProfSymtab from an object file section which
444   /// contains function PGO names. When section may contain raw
445   /// string data or string data in compressed form. This method
446   /// only initialize the symtab with reference to the data and
447   /// the section base address. The decompression will be delayed
448   /// until before it is used. See also \c create(StringRef) method.
449   Error create(object::SectionRef &Section);
450 
451   /// This interface is used by reader of CoverageMapping test
452   /// format.
453   inline Error create(StringRef D, uint64_t BaseAddr);
454 
455   /// \c NameStrings is a string composed of one of more sub-strings
456   ///  encoded in the format described in \c collectPGOFuncNameStrings.
457   /// This method is a wrapper to \c readPGOFuncNameStrings method.
458   inline Error create(StringRef NameStrings);
459 
460   /// A wrapper interface to populate the PGO symtab with functions
461   /// decls from module \c M. This interface is used by transformation
462   /// passes such as indirect function call promotion. Variable \c InLTO
463   /// indicates if this is called from LTO optimization passes.
464   Error create(Module &M, bool InLTO = false);
465 
466   /// Create InstrProfSymtab from a set of names iteratable from
467   /// \p IterRange. This interface is used by IndexedProfReader.
468   template <typename NameIterRange> Error create(const NameIterRange &IterRange);
469 
470   /// Update the symtab by adding \p FuncName to the table. This interface
471   /// is used by the raw and text profile readers.
addFuncName(StringRef FuncName)472   Error addFuncName(StringRef FuncName) {
473     if (FuncName.empty())
474       return make_error<InstrProfError>(instrprof_error::malformed);
475     auto Ins = NameTab.insert(FuncName);
476     if (Ins.second) {
477       MD5NameMap.push_back(std::make_pair(
478           IndexedInstrProf::ComputeHash(FuncName), Ins.first->getKey()));
479       Sorted = false;
480     }
481     return Error::success();
482   }
483 
484   /// Map a function address to its name's MD5 hash. This interface
485   /// is only used by the raw profiler reader.
mapAddress(uint64_t Addr,uint64_t MD5Val)486   void mapAddress(uint64_t Addr, uint64_t MD5Val) {
487     AddrToMD5Map.push_back(std::make_pair(Addr, MD5Val));
488   }
489 
490   /// Return a function's hash, or 0, if the function isn't in this SymTab.
491   uint64_t getFunctionHashFromAddress(uint64_t Address);
492 
493   /// Return function's PGO name from the function name's symbol
494   /// address in the object file. If an error occurs, return
495   /// an empty string.
496   StringRef getFuncName(uint64_t FuncNameAddress, size_t NameSize);
497 
498   /// Return function's PGO name from the name's md5 hash value.
499   /// If not found, return an empty string.
500   inline StringRef getFuncName(uint64_t FuncMD5Hash);
501 
502   /// Just like getFuncName, except that it will return a non-empty StringRef
503   /// if the function is external to this symbol table. All such cases
504   /// will be represented using the same StringRef value.
505   inline StringRef getFuncNameOrExternalSymbol(uint64_t FuncMD5Hash);
506 
507   /// True if Symbol is the value used to represent external symbols.
isExternalSymbol(const StringRef & Symbol)508   static bool isExternalSymbol(const StringRef &Symbol) {
509     return Symbol == InstrProfSymtab::getExternalSymbol();
510   }
511 
512   /// Return function from the name's md5 hash. Return nullptr if not found.
513   inline Function *getFunction(uint64_t FuncMD5Hash);
514 
515   /// Return the function's original assembly name by stripping off
516   /// the prefix attached (to symbols with priviate linkage). For
517   /// global functions, it returns the same string as getFuncName.
518   inline StringRef getOrigFuncName(uint64_t FuncMD5Hash);
519 
520   /// Return the name section data.
getNameData()521   inline StringRef getNameData() const { return Data; }
522 };
523 
create(StringRef D,uint64_t BaseAddr)524 Error InstrProfSymtab::create(StringRef D, uint64_t BaseAddr) {
525   Data = D;
526   Address = BaseAddr;
527   return Error::success();
528 }
529 
create(StringRef NameStrings)530 Error InstrProfSymtab::create(StringRef NameStrings) {
531   return readPGOFuncNameStrings(NameStrings, *this);
532 }
533 
534 template <typename NameIterRange>
create(const NameIterRange & IterRange)535 Error InstrProfSymtab::create(const NameIterRange &IterRange) {
536   for (auto Name : IterRange)
537     if (Error E = addFuncName(Name))
538       return E;
539 
540   finalizeSymtab();
541   return Error::success();
542 }
543 
finalizeSymtab()544 void InstrProfSymtab::finalizeSymtab() {
545   if (Sorted)
546     return;
547   llvm::sort(MD5NameMap.begin(), MD5NameMap.end(), less_first());
548   llvm::sort(MD5FuncMap.begin(), MD5FuncMap.end(), less_first());
549   llvm::sort(AddrToMD5Map.begin(), AddrToMD5Map.end(), less_first());
550   AddrToMD5Map.erase(std::unique(AddrToMD5Map.begin(), AddrToMD5Map.end()),
551                      AddrToMD5Map.end());
552   Sorted = true;
553 }
554 
getFuncNameOrExternalSymbol(uint64_t FuncMD5Hash)555 StringRef InstrProfSymtab::getFuncNameOrExternalSymbol(uint64_t FuncMD5Hash) {
556   StringRef ret = getFuncName(FuncMD5Hash);
557   if (ret.empty())
558     return InstrProfSymtab::getExternalSymbol();
559   return ret;
560 }
561 
getFuncName(uint64_t FuncMD5Hash)562 StringRef InstrProfSymtab::getFuncName(uint64_t FuncMD5Hash) {
563   finalizeSymtab();
564   auto Result =
565       std::lower_bound(MD5NameMap.begin(), MD5NameMap.end(), FuncMD5Hash,
566                        [](const std::pair<uint64_t, std::string> &LHS,
567                           uint64_t RHS) { return LHS.first < RHS; });
568   if (Result != MD5NameMap.end() && Result->first == FuncMD5Hash)
569     return Result->second;
570   return StringRef();
571 }
572 
getFunction(uint64_t FuncMD5Hash)573 Function* InstrProfSymtab::getFunction(uint64_t FuncMD5Hash) {
574   finalizeSymtab();
575   auto Result =
576       std::lower_bound(MD5FuncMap.begin(), MD5FuncMap.end(), FuncMD5Hash,
577                        [](const std::pair<uint64_t, Function*> &LHS,
578                           uint64_t RHS) { return LHS.first < RHS; });
579   if (Result != MD5FuncMap.end() && Result->first == FuncMD5Hash)
580     return Result->second;
581   return nullptr;
582 }
583 
584 // See also getPGOFuncName implementation. These two need to be
585 // matched.
getOrigFuncName(uint64_t FuncMD5Hash)586 StringRef InstrProfSymtab::getOrigFuncName(uint64_t FuncMD5Hash) {
587   StringRef PGOName = getFuncName(FuncMD5Hash);
588   size_t S = PGOName.find_first_of(':');
589   if (S == StringRef::npos)
590     return PGOName;
591   return PGOName.drop_front(S + 1);
592 }
593 
594 struct InstrProfValueSiteRecord {
595   /// Value profiling data pairs at a given value site.
596   std::list<InstrProfValueData> ValueData;
597 
InstrProfValueSiteRecordInstrProfValueSiteRecord598   InstrProfValueSiteRecord() { ValueData.clear(); }
599   template <class InputIterator>
InstrProfValueSiteRecordInstrProfValueSiteRecord600   InstrProfValueSiteRecord(InputIterator F, InputIterator L)
601       : ValueData(F, L) {}
602 
603   /// Sort ValueData ascending by Value
sortByTargetValuesInstrProfValueSiteRecord604   void sortByTargetValues() {
605     ValueData.sort(
606         [](const InstrProfValueData &left, const InstrProfValueData &right) {
607           return left.Value < right.Value;
608         });
609   }
610   /// Sort ValueData Descending by Count
611   inline void sortByCount();
612 
613   /// Merge data from another InstrProfValueSiteRecord
614   /// Optionally scale merged counts by \p Weight.
615   void merge(InstrProfValueSiteRecord &Input, uint64_t Weight,
616              function_ref<void(instrprof_error)> Warn);
617   /// Scale up value profile data counts.
618   void scale(uint64_t Weight, function_ref<void(instrprof_error)> Warn);
619 };
620 
621 /// Profiling information for a single function.
622 struct InstrProfRecord {
623   std::vector<uint64_t> Counts;
624 
625   InstrProfRecord() = default;
InstrProfRecordInstrProfRecord626   InstrProfRecord(std::vector<uint64_t> Counts) : Counts(std::move(Counts)) {}
627   InstrProfRecord(InstrProfRecord &&) = default;
InstrProfRecordInstrProfRecord628   InstrProfRecord(const InstrProfRecord &RHS)
629       : Counts(RHS.Counts),
630         ValueData(RHS.ValueData
631                       ? llvm::make_unique<ValueProfData>(*RHS.ValueData)
632                       : nullptr) {}
633   InstrProfRecord &operator=(InstrProfRecord &&) = default;
634   InstrProfRecord &operator=(const InstrProfRecord &RHS) {
635     Counts = RHS.Counts;
636     if (!RHS.ValueData) {
637       ValueData = nullptr;
638       return *this;
639     }
640     if (!ValueData)
641       ValueData = llvm::make_unique<ValueProfData>(*RHS.ValueData);
642     else
643       *ValueData = *RHS.ValueData;
644     return *this;
645   }
646 
647   /// Return the number of value profile kinds with non-zero number
648   /// of profile sites.
649   inline uint32_t getNumValueKinds() const;
650   /// Return the number of instrumented sites for ValueKind.
651   inline uint32_t getNumValueSites(uint32_t ValueKind) const;
652 
653   /// Return the total number of ValueData for ValueKind.
654   inline uint32_t getNumValueData(uint32_t ValueKind) const;
655 
656   /// Return the number of value data collected for ValueKind at profiling
657   /// site: Site.
658   inline uint32_t getNumValueDataForSite(uint32_t ValueKind,
659                                          uint32_t Site) const;
660 
661   /// Return the array of profiled values at \p Site. If \p TotalC
662   /// is not null, the total count of all target values at this site
663   /// will be stored in \c *TotalC.
664   inline std::unique_ptr<InstrProfValueData[]>
665   getValueForSite(uint32_t ValueKind, uint32_t Site,
666                   uint64_t *TotalC = nullptr) const;
667 
668   /// Get the target value/counts of kind \p ValueKind collected at site
669   /// \p Site and store the result in array \p Dest. Return the total
670   /// counts of all target values at this site.
671   inline uint64_t getValueForSite(InstrProfValueData Dest[], uint32_t ValueKind,
672                                   uint32_t Site) const;
673 
674   /// Reserve space for NumValueSites sites.
675   inline void reserveSites(uint32_t ValueKind, uint32_t NumValueSites);
676 
677   /// Add ValueData for ValueKind at value Site.
678   void addValueData(uint32_t ValueKind, uint32_t Site,
679                     InstrProfValueData *VData, uint32_t N,
680                     InstrProfSymtab *SymTab);
681 
682   /// Merge the counts in \p Other into this one.
683   /// Optionally scale merged counts by \p Weight.
684   void merge(InstrProfRecord &Other, uint64_t Weight,
685              function_ref<void(instrprof_error)> Warn);
686 
687   /// Scale up profile counts (including value profile data) by
688   /// \p Weight.
689   void scale(uint64_t Weight, function_ref<void(instrprof_error)> Warn);
690 
691   /// Sort value profile data (per site) by count.
sortValueDataInstrProfRecord692   void sortValueData() {
693     for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
694       for (auto &SR : getValueSitesForKind(Kind))
695         SR.sortByCount();
696   }
697 
698   /// Clear value data entries and edge counters.
ClearInstrProfRecord699   void Clear() {
700     Counts.clear();
701     clearValueData();
702   }
703 
704   /// Clear value data entries
clearValueDataInstrProfRecord705   void clearValueData() { ValueData = nullptr; }
706 
707 private:
708   struct ValueProfData {
709     std::vector<InstrProfValueSiteRecord> IndirectCallSites;
710     std::vector<InstrProfValueSiteRecord> MemOPSizes;
711   };
712   std::unique_ptr<ValueProfData> ValueData;
713 
714   MutableArrayRef<InstrProfValueSiteRecord>
getValueSitesForKindInstrProfRecord715   getValueSitesForKind(uint32_t ValueKind) {
716     // Cast to /add/ const (should be an implicit_cast, ideally, if that's ever
717     // implemented in LLVM) to call the const overload of this function, then
718     // cast away the constness from the result.
719     auto AR = const_cast<const InstrProfRecord *>(this)->getValueSitesForKind(
720         ValueKind);
721     return makeMutableArrayRef(
722         const_cast<InstrProfValueSiteRecord *>(AR.data()), AR.size());
723   }
724   ArrayRef<InstrProfValueSiteRecord>
getValueSitesForKindInstrProfRecord725   getValueSitesForKind(uint32_t ValueKind) const {
726     if (!ValueData)
727       return None;
728     switch (ValueKind) {
729     case IPVK_IndirectCallTarget:
730       return ValueData->IndirectCallSites;
731     case IPVK_MemOPSize:
732       return ValueData->MemOPSizes;
733     default:
734       llvm_unreachable("Unknown value kind!");
735     }
736   }
737 
738   std::vector<InstrProfValueSiteRecord> &
getOrCreateValueSitesForKindInstrProfRecord739   getOrCreateValueSitesForKind(uint32_t ValueKind) {
740     if (!ValueData)
741       ValueData = llvm::make_unique<ValueProfData>();
742     switch (ValueKind) {
743     case IPVK_IndirectCallTarget:
744       return ValueData->IndirectCallSites;
745     case IPVK_MemOPSize:
746       return ValueData->MemOPSizes;
747     default:
748       llvm_unreachable("Unknown value kind!");
749     }
750   }
751 
752   // Map indirect call target name hash to name string.
753   uint64_t remapValue(uint64_t Value, uint32_t ValueKind,
754                       InstrProfSymtab *SymTab);
755 
756   // Merge Value Profile data from Src record to this record for ValueKind.
757   // Scale merged value counts by \p Weight.
758   void mergeValueProfData(uint32_t ValkeKind, InstrProfRecord &Src,
759                           uint64_t Weight,
760                           function_ref<void(instrprof_error)> Warn);
761 
762   // Scale up value profile data count.
763   void scaleValueProfData(uint32_t ValueKind, uint64_t Weight,
764                           function_ref<void(instrprof_error)> Warn);
765 };
766 
767 struct NamedInstrProfRecord : InstrProfRecord {
768   StringRef Name;
769   uint64_t Hash;
770 
771   NamedInstrProfRecord() = default;
NamedInstrProfRecordNamedInstrProfRecord772   NamedInstrProfRecord(StringRef Name, uint64_t Hash,
773                        std::vector<uint64_t> Counts)
774       : InstrProfRecord(std::move(Counts)), Name(Name), Hash(Hash) {}
775 };
776 
getNumValueKinds()777 uint32_t InstrProfRecord::getNumValueKinds() const {
778   uint32_t NumValueKinds = 0;
779   for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
780     NumValueKinds += !(getValueSitesForKind(Kind).empty());
781   return NumValueKinds;
782 }
783 
getNumValueData(uint32_t ValueKind)784 uint32_t InstrProfRecord::getNumValueData(uint32_t ValueKind) const {
785   uint32_t N = 0;
786   for (auto &SR : getValueSitesForKind(ValueKind))
787     N += SR.ValueData.size();
788   return N;
789 }
790 
getNumValueSites(uint32_t ValueKind)791 uint32_t InstrProfRecord::getNumValueSites(uint32_t ValueKind) const {
792   return getValueSitesForKind(ValueKind).size();
793 }
794 
getNumValueDataForSite(uint32_t ValueKind,uint32_t Site)795 uint32_t InstrProfRecord::getNumValueDataForSite(uint32_t ValueKind,
796                                                  uint32_t Site) const {
797   return getValueSitesForKind(ValueKind)[Site].ValueData.size();
798 }
799 
800 std::unique_ptr<InstrProfValueData[]>
getValueForSite(uint32_t ValueKind,uint32_t Site,uint64_t * TotalC)801 InstrProfRecord::getValueForSite(uint32_t ValueKind, uint32_t Site,
802                                  uint64_t *TotalC) const {
803   uint64_t Dummy;
804   uint64_t &TotalCount = (TotalC == nullptr ? Dummy : *TotalC);
805   uint32_t N = getNumValueDataForSite(ValueKind, Site);
806   if (N == 0) {
807     TotalCount = 0;
808     return std::unique_ptr<InstrProfValueData[]>(nullptr);
809   }
810 
811   auto VD = llvm::make_unique<InstrProfValueData[]>(N);
812   TotalCount = getValueForSite(VD.get(), ValueKind, Site);
813 
814   return VD;
815 }
816 
getValueForSite(InstrProfValueData Dest[],uint32_t ValueKind,uint32_t Site)817 uint64_t InstrProfRecord::getValueForSite(InstrProfValueData Dest[],
818                                           uint32_t ValueKind,
819                                           uint32_t Site) const {
820   uint32_t I = 0;
821   uint64_t TotalCount = 0;
822   for (auto V : getValueSitesForKind(ValueKind)[Site].ValueData) {
823     Dest[I].Value = V.Value;
824     Dest[I].Count = V.Count;
825     TotalCount = SaturatingAdd(TotalCount, V.Count);
826     I++;
827   }
828   return TotalCount;
829 }
830 
reserveSites(uint32_t ValueKind,uint32_t NumValueSites)831 void InstrProfRecord::reserveSites(uint32_t ValueKind, uint32_t NumValueSites) {
832   if (!NumValueSites)
833     return;
834   getOrCreateValueSitesForKind(ValueKind).reserve(NumValueSites);
835 }
836 
getHostEndianness()837 inline support::endianness getHostEndianness() {
838   return sys::IsLittleEndianHost ? support::little : support::big;
839 }
840 
841 // Include definitions for value profile data
842 #define INSTR_PROF_VALUE_PROF_DATA
843 #include "llvm/ProfileData/InstrProfData.inc"
844 
sortByCount()845 void InstrProfValueSiteRecord::sortByCount() {
846   ValueData.sort(
847       [](const InstrProfValueData &left, const InstrProfValueData &right) {
848         return left.Count > right.Count;
849       });
850   // Now truncate
851   size_t max_s = INSTR_PROF_MAX_NUM_VAL_PER_SITE;
852   if (ValueData.size() > max_s)
853     ValueData.resize(max_s);
854 }
855 
856 namespace IndexedInstrProf {
857 
858 enum class HashT : uint32_t {
859   MD5,
860   Last = MD5
861 };
862 
ComputeHash(HashT Type,StringRef K)863 inline uint64_t ComputeHash(HashT Type, StringRef K) {
864   switch (Type) {
865   case HashT::MD5:
866     return MD5Hash(K);
867   }
868   llvm_unreachable("Unhandled hash type");
869 }
870 
871 const uint64_t Magic = 0x8169666f72706cff; // "\xfflprofi\x81"
872 
873 enum ProfVersion {
874   // Version 1 is the first version. In this version, the value of
875   // a key/value pair can only include profile data of a single function.
876   // Due to this restriction, the number of block counters for a given
877   // function is not recorded but derived from the length of the value.
878   Version1 = 1,
879   // The version 2 format supports recording profile data of multiple
880   // functions which share the same key in one value field. To support this,
881   // the number block counters is recorded as an uint64_t field right after the
882   // function structural hash.
883   Version2 = 2,
884   // Version 3 supports value profile data. The value profile data is expected
885   // to follow the block counter profile data.
886   Version3 = 3,
887   // In this version, profile summary data \c IndexedInstrProf::Summary is
888   // stored after the profile header.
889   Version4 = 4,
890   // In this version, the frontend PGO stable hash algorithm defaults to V2.
891   Version5 = 5,
892   // The current version is 5.
893   CurrentVersion = INSTR_PROF_INDEX_VERSION
894 };
895 const uint64_t Version = ProfVersion::CurrentVersion;
896 
897 const HashT HashType = HashT::MD5;
898 
ComputeHash(StringRef K)899 inline uint64_t ComputeHash(StringRef K) { return ComputeHash(HashType, K); }
900 
901 // This structure defines the file header of the LLVM profile
902 // data file in indexed-format.
903 struct Header {
904   uint64_t Magic;
905   uint64_t Version;
906   uint64_t Unused; // Becomes unused since version 4
907   uint64_t HashType;
908   uint64_t HashOffset;
909 };
910 
911 // Profile summary data recorded in the profile data file in indexed
912 // format. It is introduced in version 4. The summary data follows
913 // right after the profile file header.
914 struct Summary {
915   struct Entry {
916     uint64_t Cutoff; ///< The required percentile of total execution count.
917     uint64_t
918         MinBlockCount;  ///< The minimum execution count for this percentile.
919     uint64_t NumBlocks; ///< Number of blocks >= the minumum execution count.
920   };
921   // The field kind enumerator to assigned value mapping should remain
922   // unchanged  when a new kind is added or an old kind gets deleted in
923   // the future.
924   enum SummaryFieldKind {
925     /// The total number of functions instrumented.
926     TotalNumFunctions = 0,
927     /// Total number of instrumented blocks/edges.
928     TotalNumBlocks = 1,
929     /// The maximal execution count among all functions.
930     /// This field does not exist for profile data from IR based
931     /// instrumentation.
932     MaxFunctionCount = 2,
933     /// Max block count of the program.
934     MaxBlockCount = 3,
935     /// Max internal block count of the program (excluding entry blocks).
936     MaxInternalBlockCount = 4,
937     /// The sum of all instrumented block counts.
938     TotalBlockCount = 5,
939     NumKinds = TotalBlockCount + 1
940   };
941 
942   // The number of summmary fields following the summary header.
943   uint64_t NumSummaryFields;
944   // The number of Cutoff Entries (Summary::Entry) following summary fields.
945   uint64_t NumCutoffEntries;
946 
947   Summary() = delete;
SummarySummary948   Summary(uint32_t Size) { memset(this, 0, Size); }
949 
deleteSummary950   void operator delete(void *ptr) { ::operator delete(ptr); }
951 
getSizeSummary952   static uint32_t getSize(uint32_t NumSumFields, uint32_t NumCutoffEntries) {
953     return sizeof(Summary) + NumCutoffEntries * sizeof(Entry) +
954            NumSumFields * sizeof(uint64_t);
955   }
956 
getSummaryDataBaseSummary957   const uint64_t *getSummaryDataBase() const {
958     return reinterpret_cast<const uint64_t *>(this + 1);
959   }
960 
getSummaryDataBaseSummary961   uint64_t *getSummaryDataBase() {
962     return reinterpret_cast<uint64_t *>(this + 1);
963   }
964 
getCutoffEntryBaseSummary965   const Entry *getCutoffEntryBase() const {
966     return reinterpret_cast<const Entry *>(
967         &getSummaryDataBase()[NumSummaryFields]);
968   }
969 
getCutoffEntryBaseSummary970   Entry *getCutoffEntryBase() {
971     return reinterpret_cast<Entry *>(&getSummaryDataBase()[NumSummaryFields]);
972   }
973 
getSummary974   uint64_t get(SummaryFieldKind K) const {
975     return getSummaryDataBase()[K];
976   }
977 
setSummary978   void set(SummaryFieldKind K, uint64_t V) {
979     getSummaryDataBase()[K] = V;
980   }
981 
getEntrySummary982   const Entry &getEntry(uint32_t I) const { return getCutoffEntryBase()[I]; }
983 
setEntrySummary984   void setEntry(uint32_t I, const ProfileSummaryEntry &E) {
985     Entry &ER = getCutoffEntryBase()[I];
986     ER.Cutoff = E.Cutoff;
987     ER.MinBlockCount = E.MinCount;
988     ER.NumBlocks = E.NumCounts;
989   }
990 };
991 
allocSummary(uint32_t TotalSize)992 inline std::unique_ptr<Summary> allocSummary(uint32_t TotalSize) {
993   return std::unique_ptr<Summary>(new (::operator new(TotalSize))
994                                       Summary(TotalSize));
995 }
996 
997 } // end namespace IndexedInstrProf
998 
999 namespace RawInstrProf {
1000 
1001 // Version 1: First version
1002 // Version 2: Added value profile data section. Per-function control data
1003 // struct has more fields to describe value profile information.
1004 // Version 3: Compressed name section support. Function PGO name reference
1005 // from control data struct is changed from raw pointer to Name's MD5 value.
1006 // Version 4: ValueDataBegin and ValueDataSizes fields are removed from the
1007 // raw header.
1008 const uint64_t Version = INSTR_PROF_RAW_VERSION;
1009 
1010 template <class IntPtrT> inline uint64_t getMagic();
1011 template <> inline uint64_t getMagic<uint64_t>() {
1012   return INSTR_PROF_RAW_MAGIC_64;
1013 }
1014 
1015 template <> inline uint64_t getMagic<uint32_t>() {
1016   return INSTR_PROF_RAW_MAGIC_32;
1017 }
1018 
1019 // Per-function profile data header/control structure.
1020 // The definition should match the structure defined in
1021 // compiler-rt/lib/profile/InstrProfiling.h.
1022 // It should also match the synthesized type in
1023 // Transforms/Instrumentation/InstrProfiling.cpp:getOrCreateRegionCounters.
1024 template <class IntPtrT> struct alignas(8) ProfileData {
1025   #define INSTR_PROF_DATA(Type, LLVMType, Name, Init) Type Name;
1026   #include "llvm/ProfileData/InstrProfData.inc"
1027 };
1028 
1029 // File header structure of the LLVM profile data in raw format.
1030 // The definition should match the header referenced in
1031 // compiler-rt/lib/profile/InstrProfilingFile.c  and
1032 // InstrProfilingBuffer.c.
1033 struct Header {
1034 #define INSTR_PROF_RAW_HEADER(Type, Name, Init) const Type Name;
1035 #include "llvm/ProfileData/InstrProfData.inc"
1036 };
1037 
1038 } // end namespace RawInstrProf
1039 
1040 // Parse MemOP Size range option.
1041 void getMemOPSizeRangeFromOption(StringRef Str, int64_t &RangeStart,
1042                                  int64_t &RangeLast);
1043 
1044 } // end namespace llvm
1045 
1046 #endif // LLVM_PROFILEDATA_INSTRPROF_H
1047