1 files changed, 248 insertions, 0 deletions
diff --git a/include/llvm/ProfileData/SampleProf.h b/include/llvm/ProfileData/SampleProf.h
new file mode 100644
index 0000000..5c70b31
--- /dev/null
+++ b/include/llvm/ProfileData/SampleProf.h
@@ -0,0 +1,248 @@
+//=-- SampleProf.h - Sampling profiling format support --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains common definitions used in the reading and writing of
+// sample profile data.
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_PROFILEDATA_SAMPLEPROF_H_
+#define LLVM_PROFILEDATA_SAMPLEPROF_H_
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include <system_error>
+
+namespace llvm {
+
+const std::error_category &sampleprof_category();
+
+enum class sampleprof_error {
+  success = 0,
+  bad_magic,
+  unsupported_version,
+  too_large,
+  truncated,
+  malformed,
+  unrecognized_format
+};
+
+inline std::error_code make_error_code(sampleprof_error E) {
+  return std::error_code(static_cast<int>(E), sampleprof_category());
+}
+
+} // end namespace llvm
+
+namespace std {
+template <>
+struct is_error_code_enum<llvm::sampleprof_error> : std::true_type {};
+}
+
+namespace llvm {
+
+namespace sampleprof {
+
+static inline uint64_t SPMagic() {
+  return uint64_t('S') << (64 - 8) | uint64_t('P') << (64 - 16) |
+         uint64_t('R') << (64 - 24) | uint64_t('O') << (64 - 32) |
+         uint64_t('F') << (64 - 40) | uint64_t('4') << (64 - 48) |
+         uint64_t('2') << (64 - 56) | uint64_t(0xff);
+}
+
+static inline uint64_t SPVersion() { return 100; }
+
+/// \brief Represents the relative location of an instruction.
+///
+/// Instruction locations are specified by the line offset from the
+/// beginning of the function (marked by the line where the function
+/// header is) and the discriminator value within that line.
+///
+/// The discriminator value is useful to distinguish instructions
+/// that are on the same line but belong to different basic blocks
+/// (e.g., the two post-increment instructions in "if (p) x++; else y++;").
+struct LineLocation {
+  LineLocation(int L, unsigned D) : LineOffset(L), Discriminator(D) {}
+  int LineOffset;
+  unsigned Discriminator;
+};
+
+} // End namespace sampleprof
+
+template <> struct DenseMapInfo<sampleprof::LineLocation> {
+  typedef DenseMapInfo<int> OffsetInfo;
+  typedef DenseMapInfo<unsigned> DiscriminatorInfo;
+  static inline sampleprof::LineLocation getEmptyKey() {
+    return sampleprof::LineLocation(OffsetInfo::getEmptyKey(),
+                                    DiscriminatorInfo::getEmptyKey());
+  }
+  static inline sampleprof::LineLocation getTombstoneKey() {
+    return sampleprof::LineLocation(OffsetInfo::getTombstoneKey(),
+                                    DiscriminatorInfo::getTombstoneKey());
+  }
+  static inline unsigned getHashValue(sampleprof::LineLocation Val) {
+    return DenseMapInfo<std::pair<int, unsigned>>::getHashValue(
+        std::pair<int, unsigned>(Val.LineOffset, Val.Discriminator));
+  }
+  static inline bool isEqual(sampleprof::LineLocation LHS,
+                             sampleprof::LineLocation RHS) {
+    return LHS.LineOffset == RHS.LineOffset &&
+           LHS.Discriminator == RHS.Discriminator;
+  }
+};
+
+namespace sampleprof {
+
+/// \brief Representation of a single sample record.
+///
+/// A sample record is represented by a positive integer value, which
+/// indicates how frequently was the associated line location executed.
+///
+/// Additionally, if the associated location contains a function call,
+/// the record will hold a list of all the possible called targets. For
+/// direct calls, this will be the exact function being invoked. For
+/// indirect calls (function pointers, virtual table dispatch), this
+/// will be a list of one or more functions.
+class SampleRecord {
+public:
+  typedef StringMap<unsigned> CallTargetMap;
+
+  SampleRecord() : NumSamples(0), CallTargets() {}
+
+  /// \brief Increment the number of samples for this record by \p S.
+  ///
+  /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
+  /// around unsigned integers.
+  void addSamples(unsigned S) {
+    if (NumSamples <= std::numeric_limits<unsigned>::max() - S)
+      NumSamples += S;
+    else
+      NumSamples = std::numeric_limits<unsigned>::max();
+  }
+
+  /// \brief Add called function \p F with samples \p S.
+  ///
+  /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
+  /// around unsigned integers.
+  void addCalledTarget(StringRef F, unsigned S) {
+    unsigned &TargetSamples = CallTargets[F];
+    if (TargetSamples <= std::numeric_limits<unsigned>::max() - S)
+      TargetSamples += S;
+    else
+      TargetSamples = std::numeric_limits<unsigned>::max();
+  }
+
+  /// \brief Return true if this sample record contains function calls.
+  bool hasCalls() const { return CallTargets.size() > 0; }
+
+  unsigned getSamples() const { return NumSamples; }
+  const CallTargetMap &getCallTargets() const { return CallTargets; }
+
+  /// \brief Merge the samples in \p Other into this record.
+  void merge(const SampleRecord &Other) {
+    addSamples(Other.getSamples());
+    for (const auto &I : Other.getCallTargets())
+      addCalledTarget(I.first(), I.second);
+  }
+
+private:
+  unsigned NumSamples;
+  CallTargetMap CallTargets;
+};
+
+typedef DenseMap<LineLocation, SampleRecord> BodySampleMap;
+
+/// \brief Representation of the samples collected for a function.
+///
+/// This data structure contains all the collected samples for the body
+/// of a function. Each sample corresponds to a LineLocation instance
+/// within the body of the function.
+class FunctionSamples {
+public:
+  FunctionSamples() : TotalSamples(0), TotalHeadSamples(0) {}
+  void print(raw_ostream &OS = dbgs());
+  void addTotalSamples(unsigned Num) { TotalSamples += Num; }
+  void addHeadSamples(unsigned Num) { TotalHeadSamples += Num; }
+  void addBodySamples(int LineOffset, unsigned Discriminator, unsigned Num) {
+    assert(LineOffset >= 0);
+    // When dealing with instruction weights, we use the value
+    // zero to indicate the absence of a sample. If we read an
+    // actual zero from the profile file, use the value 1 to
+    // avoid the confusion later on.
+    if (Num == 0)
+      Num = 1;
+    BodySamples[LineLocation(LineOffset, Discriminator)].addSamples(Num);
+  }
+  void addCalledTargetSamples(int LineOffset, unsigned Discriminator,
+                              std::string FName, unsigned Num) {
+    assert(LineOffset >= 0);
+    BodySamples[LineLocation(LineOffset, Discriminator)].addCalledTarget(FName,
+                                                                         Num);
+  }
+
+  /// \brief Return the sample record at the given location.
+  /// Each location is specified by \p LineOffset and \p Discriminator.
+  SampleRecord &sampleRecordAt(const LineLocation &Loc) {
+    return BodySamples[Loc];
+  }
+
+  /// \brief Return the number of samples collected at the given location.
+  /// Each location is specified by \p LineOffset and \p Discriminator.
+  unsigned samplesAt(int LineOffset, unsigned Discriminator) {
+    return sampleRecordAt(LineLocation(LineOffset, Discriminator)).getSamples();
+  }
+
+  bool empty() const { return BodySamples.empty(); }
+
+  /// \brief Return the total number of samples collected inside the function.
+  unsigned getTotalSamples() const { return TotalSamples; }
+
+  /// \brief Return the total number of samples collected at the head of the
+  /// function.
+  unsigned getHeadSamples() const { return TotalHeadSamples; }
+
+  /// \brief Return all the samples collected in the body of the function.
+  const BodySampleMap &getBodySamples() const { return BodySamples; }
+
+  /// \brief Merge the samples in \p Other into this one.
+  void merge(const FunctionSamples &Other) {
+    addTotalSamples(Other.getTotalSamples());
+    addHeadSamples(Other.getHeadSamples());
+    for (const auto &I : Other.getBodySamples()) {
+      const LineLocation &Loc = I.first;
+      const SampleRecord &Rec = I.second;
+      sampleRecordAt(Loc).merge(Rec);
+    }
+  }
+
+private:
+  /// \brief Total number of samples collected inside this function.
+  ///
+  /// Samples are cumulative, they include all the samples collected
+  /// inside this function and all its inlined callees.
+  unsigned TotalSamples;
+
+  /// \brief Total number of samples collected at the head of the function.
+  unsigned TotalHeadSamples;
+
+  /// \brief Map instruction locations to collected samples.
+  ///
+  /// Each entry in this map contains the number of samples
+  /// collected at the corresponding line offset. All line locations
+  /// are an offset from the start of the function.
+  BodySampleMap BodySamples;
+};
+
+} // End namespace sampleprof
+
+} // End namespace llvm
+
+#endif // LLVM_PROFILEDATA_SAMPLEPROF_H_