1 //=-- SampleProf.h - Sampling profiling format support --------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains common definitions used in the reading and writing of
11 // sample profile data.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_PROFILEDATA_SAMPLEPROF_H_
16 #define LLVM_PROFILEDATA_SAMPLEPROF_H_
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/ADT/StringMap.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/ErrorOr.h"
22 #include "llvm/Support/raw_ostream.h"
25 #include <system_error>
29 const std::error_category &sampleprof_category();
31 enum class sampleprof_error {
39 unsupported_writing_format,
45 inline std::error_code make_error_code(sampleprof_error E) {
46 return std::error_code(static_cast<int>(E), sampleprof_category());
49 inline sampleprof_error MergeResult(sampleprof_error &Accumulator,
50 sampleprof_error Result) {
51 // Prefer first error encountered as later errors may be secondary effects of
52 // the initial problem.
53 if (Accumulator == sampleprof_error::success &&
54 Result != sampleprof_error::success)
59 } // end namespace llvm
63 struct is_error_code_enum<llvm::sampleprof_error> : std::true_type {};
68 namespace sampleprof {
70 static inline uint64_t SPMagic() {
71 return uint64_t('S') << (64 - 8) | uint64_t('P') << (64 - 16) |
72 uint64_t('R') << (64 - 24) | uint64_t('O') << (64 - 32) |
73 uint64_t('F') << (64 - 40) | uint64_t('4') << (64 - 48) |
74 uint64_t('2') << (64 - 56) | uint64_t(0xff);
77 static inline uint64_t SPVersion() { return 102; }
79 /// Represents the relative location of an instruction.
81 /// Instruction locations are specified by the line offset from the
82 /// beginning of the function (marked by the line where the function
83 /// header is) and the discriminator value within that line.
85 /// The discriminator value is useful to distinguish instructions
86 /// that are on the same line but belong to different basic blocks
87 /// (e.g., the two post-increment instructions in "if (p) x++; else y++;").
89 LineLocation(uint32_t L, uint32_t D) : LineOffset(L), Discriminator(D) {}
90 void print(raw_ostream &OS) const;
92 bool operator<(const LineLocation &O) const {
93 return LineOffset < O.LineOffset ||
94 (LineOffset == O.LineOffset && Discriminator < O.Discriminator);
98 uint32_t Discriminator;
101 raw_ostream &operator<<(raw_ostream &OS, const LineLocation &Loc);
103 /// Represents the relative location of a callsite.
105 /// Callsite locations are specified by the line offset from the
106 /// beginning of the function (marked by the line where the function
107 /// head is), the discriminator value within that line, and the callee
109 struct CallsiteLocation : public LineLocation {
110 CallsiteLocation(uint32_t L, uint32_t D, StringRef N)
111 : LineLocation(L, D), CalleeName(N) {}
112 void print(raw_ostream &OS) const;
115 StringRef CalleeName;
118 raw_ostream &operator<<(raw_ostream &OS, const CallsiteLocation &Loc);
120 /// Representation of a single sample record.
122 /// A sample record is represented by a positive integer value, which
123 /// indicates how frequently was the associated line location executed.
125 /// Additionally, if the associated location contains a function call,
126 /// the record will hold a list of all the possible called targets. For
127 /// direct calls, this will be the exact function being invoked. For
128 /// indirect calls (function pointers, virtual table dispatch), this
129 /// will be a list of one or more functions.
132 typedef StringMap<uint64_t> CallTargetMap;
134 SampleRecord() : NumSamples(0), CallTargets() {}
136 /// Increment the number of samples for this record by \p S.
137 /// Optionally scale sample count \p S by \p Weight.
139 /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
140 /// around unsigned integers.
141 sampleprof_error addSamples(uint64_t S, uint64_t Weight = 1) {
144 S = SaturatingMultiply(S, Weight, &Overflowed);
146 return sampleprof_error::counter_overflow;
148 NumSamples = SaturatingAdd(NumSamples, S, &Overflowed);
150 return sampleprof_error::counter_overflow;
152 return sampleprof_error::success;
155 /// Add called function \p F with samples \p S.
156 /// Optionally scale sample count \p S by \p Weight.
158 /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
159 /// around unsigned integers.
160 sampleprof_error addCalledTarget(StringRef F, uint64_t S,
161 uint64_t Weight = 1) {
162 uint64_t &TargetSamples = CallTargets[F];
165 S = SaturatingMultiply(S, Weight, &Overflowed);
167 return sampleprof_error::counter_overflow;
169 TargetSamples = SaturatingAdd(TargetSamples, S, &Overflowed);
171 return sampleprof_error::counter_overflow;
173 return sampleprof_error::success;
176 /// Return true if this sample record contains function calls.
177 bool hasCalls() const { return CallTargets.size() > 0; }
179 uint64_t getSamples() const { return NumSamples; }
180 const CallTargetMap &getCallTargets() const { return CallTargets; }
182 /// Merge the samples in \p Other into this record.
183 /// Optionally scale sample counts by \p Weight.
184 sampleprof_error merge(const SampleRecord &Other, uint64_t Weight = 1) {
185 sampleprof_error Result = addSamples(Other.getSamples(), Weight);
186 for (const auto &I : Other.getCallTargets()) {
187 MergeResult(Result, addCalledTarget(I.first(), I.second, Weight));
192 void print(raw_ostream &OS, unsigned Indent) const;
197 CallTargetMap CallTargets;
200 raw_ostream &operator<<(raw_ostream &OS, const SampleRecord &Sample);
202 typedef std::map<LineLocation, SampleRecord> BodySampleMap;
203 class FunctionSamples;
204 typedef std::map<CallsiteLocation, FunctionSamples> CallsiteSampleMap;
206 /// Representation of the samples collected for a function.
208 /// This data structure contains all the collected samples for the body
209 /// of a function. Each sample corresponds to a LineLocation instance
210 /// within the body of the function.
211 class FunctionSamples {
213 FunctionSamples() : TotalSamples(0), TotalHeadSamples(0) {}
214 void print(raw_ostream &OS = dbgs(), unsigned Indent = 0) const;
216 sampleprof_error addTotalSamples(uint64_t Num, uint64_t Weight = 1) {
219 Num = SaturatingMultiply(Num, Weight, &Overflowed);
221 return sampleprof_error::counter_overflow;
223 TotalSamples = SaturatingAdd(TotalSamples, Num, &Overflowed);
225 return sampleprof_error::counter_overflow;
227 return sampleprof_error::success;
229 sampleprof_error addHeadSamples(uint64_t Num, uint64_t Weight = 1) {
232 Num = SaturatingMultiply(Num, Weight, &Overflowed);
234 return sampleprof_error::counter_overflow;
236 TotalHeadSamples = SaturatingAdd(TotalHeadSamples, Num, &Overflowed);
238 return sampleprof_error::counter_overflow;
240 return sampleprof_error::success;
242 sampleprof_error addBodySamples(uint32_t LineOffset, uint32_t Discriminator,
243 uint64_t Num, uint64_t Weight = 1) {
244 return BodySamples[LineLocation(LineOffset, Discriminator)].addSamples(
247 sampleprof_error addCalledTargetSamples(uint32_t LineOffset,
248 uint32_t Discriminator,
249 std::string FName, uint64_t Num,
250 uint64_t Weight = 1) {
251 return BodySamples[LineLocation(LineOffset, Discriminator)].addCalledTarget(
255 /// Return the number of samples collected at the given location.
256 /// Each location is specified by \p LineOffset and \p Discriminator.
257 /// If the location is not found in profile, return error.
258 ErrorOr<uint64_t> findSamplesAt(uint32_t LineOffset,
259 uint32_t Discriminator) const {
260 const auto &ret = BodySamples.find(LineLocation(LineOffset, Discriminator));
261 if (ret == BodySamples.end())
262 return std::error_code();
264 return ret->second.getSamples();
267 /// Return the function samples at the given callsite location.
268 FunctionSamples &functionSamplesAt(const CallsiteLocation &Loc) {
269 return CallsiteSamples[Loc];
272 /// Return a pointer to function samples at the given callsite location.
273 const FunctionSamples *
274 findFunctionSamplesAt(const CallsiteLocation &Loc) const {
275 auto iter = CallsiteSamples.find(Loc);
276 if (iter == CallsiteSamples.end()) {
279 return &iter->second;
283 bool empty() const { return TotalSamples == 0; }
285 /// Return the total number of samples collected inside the function.
286 uint64_t getTotalSamples() const { return TotalSamples; }
288 /// Return the total number of samples collected at the head of the
290 uint64_t getHeadSamples() const { return TotalHeadSamples; }
292 /// Return all the samples collected in the body of the function.
293 const BodySampleMap &getBodySamples() const { return BodySamples; }
295 /// Return all the callsite samples collected in the body of the function.
296 const CallsiteSampleMap &getCallsiteSamples() const {
297 return CallsiteSamples;
300 /// Merge the samples in \p Other into this one.
301 /// Optionally scale samples by \p Weight.
302 sampleprof_error merge(const FunctionSamples &Other, uint64_t Weight = 1) {
303 sampleprof_error Result = sampleprof_error::success;
304 MergeResult(Result, addTotalSamples(Other.getTotalSamples(), Weight));
305 MergeResult(Result, addHeadSamples(Other.getHeadSamples(), Weight));
306 for (const auto &I : Other.getBodySamples()) {
307 const LineLocation &Loc = I.first;
308 const SampleRecord &Rec = I.second;
309 MergeResult(Result, BodySamples[Loc].merge(Rec, Weight));
311 for (const auto &I : Other.getCallsiteSamples()) {
312 const CallsiteLocation &Loc = I.first;
313 const FunctionSamples &Rec = I.second;
314 MergeResult(Result, functionSamplesAt(Loc).merge(Rec, Weight));
320 /// Total number of samples collected inside this function.
322 /// Samples are cumulative, they include all the samples collected
323 /// inside this function and all its inlined callees.
324 uint64_t TotalSamples;
326 /// Total number of samples collected at the head of the function.
327 /// This is an approximation of the number of calls made to this function
329 uint64_t TotalHeadSamples;
331 /// Map instruction locations to collected samples.
333 /// Each entry in this map contains the number of samples
334 /// collected at the corresponding line offset. All line locations
335 /// are an offset from the start of the function.
336 BodySampleMap BodySamples;
338 /// Map call sites to collected samples for the called function.
340 /// Each entry in this map corresponds to all the samples
341 /// collected for the inlined function call at the given
342 /// location. For example, given:
350 /// If the bar() and baz() calls were inlined inside foo(), this
351 /// map will contain two entries. One for all the samples collected
352 /// in the call to bar() at line offset 1, the other for all the samples
353 /// collected in the call to baz() at line offset 8.
354 CallsiteSampleMap CallsiteSamples;
357 raw_ostream &operator<<(raw_ostream &OS, const FunctionSamples &FS);
359 /// Sort a LocationT->SampleT map by LocationT.
361 /// It produces a sorted list of <LocationT, SampleT> records by ascending
362 /// order of LocationT.
363 template <class LocationT, class SampleT> class SampleSorter {
365 typedef std::pair<const LocationT, SampleT> SamplesWithLoc;
366 typedef SmallVector<const SamplesWithLoc *, 20> SamplesWithLocList;
368 SampleSorter(const std::map<LocationT, SampleT> &Samples) {
369 for (const auto &I : Samples)
371 std::stable_sort(V.begin(), V.end(),
372 [](const SamplesWithLoc *A, const SamplesWithLoc *B) {
373 return A->first < B->first;
376 const SamplesWithLocList &get() const { return V; }
379 SamplesWithLocList V;
382 } // end namespace sampleprof
384 } // end namespace llvm
386 #endif // LLVM_PROFILEDATA_SAMPLEPROF_H_