Sample profile summary cleanup

[eraman]

Summary

Replace references to MaxHeadSamples with MaxFunctionCount

[dnovillo]

LGTM

Nothing here seems to change the format of the external file, but could you double check with the AutoFDO converter that we can still read Perf profiles?

Thanks!

[eraman]

In D18522#384855, @dnovillo wrote:

LGTM

Nothing here seems to change the format of the external file, but could you double check with the AutoFDO converter that we can still read Perf profiles?

Thanks!

Verified that this doesn't break the converter. Will submit this change.

include/llvm/ProfileData/ProfileCommon.h

 
 class SampleProfileSummary final : public ProfileSummary {
 protected:
   std::vector<Metadata *> getFormatSpecificMD(LLVMContext &Context) override;
 
 public:
   uint32_t getNumLinesWithSamples() { return NumCounts; }
   uint64_t getTotalSamples() { return TotalCount; }
-  uint64_t getMaxHeadSamples() { return MaxFunctionCount; }
   uint64_t getMaxSamplesPerLine() { return MaxCount; }
   void addRecord(const sampleprof::FunctionSamples &FS);
   SampleProfileSummary(std::vector<uint32_t> Cutoffs)
       : ProfileSummary(PSK_Sample, Cutoffs) {}
   SampleProfileSummary(uint64_t TotalSamples, uint64_t MaxSamplesPerLine,
-                       uint64_t MaxHeadSamples, int32_t NumLinesWithSamples,
+                       uint64_t MaxFunctionCount, int32_t NumLinesWithSamples,
                        uint32_t NumFunctions,
                        SummaryEntryVector DetailedSummary)
       : ProfileSummary(PSK_Sample, DetailedSummary, TotalSamples,
-                       MaxSamplesPerLine, MaxHeadSamples, NumLinesWithSamples,
+                       MaxSamplesPerLine, MaxFunctionCount, NumLinesWithSamples,
                        NumFunctions) {}
   static bool classof(const ProfileSummary *PS) {
     return PS->getKind() == PSK_Sample;
   }
 };
 
 // This is called when a count is seen in the profile.
 void ProfileSummary::addCount(uint64_t Count) {

include/llvm/ProfileData/SampleProfReader.h

 // VERSION (uint32_t)
 //    File format version number computed by SPVersion()
 //
 // SUMMARY
 //    TOTAL_COUNT (uint64_t)
 //        Total number of samples in the profile.
 //    MAX_COUNT (uint64_t)
 //        Maximum value of samples on a line.
-//    MAX_HEAD_SAMPLES (uint64_t)
-//        Maximum number of head samples.
+//    MAX_FUNCTION_COUNT (uint64_t)
+//        Maximum number of samples at function entry (head samples).
 //    NUM_COUNTS (uint64_t)
 //        Number of lines with samples.
 //    NUM_FUNCTIONS (uint64_t)
 //        Number of functions with samples.
 //    NUM_DETAILED_SUMMARY_ENTRIES (size_t)
 //        Number of entries in detailed summary
 //    DETAILED_SUMMARY
 //        A list of detailed summary entry. Each entry consists of

lib/ProfileData/ProfileSummary.cpp

 std::vector<Metadata *>
 SampleProfileSummary::getFormatSpecificMD(LLVMContext &Context) {
   std::vector<Metadata *> Components;
 
   Components.push_back(getKeyValMD(Context, "TotalSamples", getTotalSamples()));
   Components.push_back(
       getKeyValMD(Context, "MaxSamplesPerLine", getMaxSamplesPerLine()));
   Components.push_back(
-      getKeyValMD(Context, "MaxHeadSamples", getMaxHeadSamples()));
+      getKeyValMD(Context, "MaxFunctionCount", getMaxFunctionCount()));
   Components.push_back(
       getKeyValMD(Context, "NumLinesWithSamples", getNumLinesWithSamples()));
   Components.push_back(getKeyValMD(Context, "NumFunctions", NumFunctions));
 
   Components.push_back(getDetailedSummaryMD(Context));
   return Components;
 }
 
if (!getSummaryFromMD(dyn_cast<MDTuple>(Tuple->getOperand(7)), Summary))
     return nullptr;
   return new InstrProfSummary(TotalCount, MaxBlockCount, MaxInternalBlockCount,
                               MaxFunctionCount, NumBlocks, NumFunctions,
                               Summary);
 }
 
 // Parse an MDTuple representing a SampleProfileSummary object.
 static ProfileSummary *getSampleProfileSummaryFromMD(MDTuple *Tuple) {
-  uint64_t TotalSamples, MaxSamplesPerLine, MaxHeadSamples, NumLinesWithSamples,
-      NumFunctions;
+  uint64_t TotalSamples, MaxSamplesPerLine, MaxFunctionCount,
+      NumLinesWithSamples, NumFunctions;
   SummaryEntryVector Summary;
 
   if (Tuple->getNumOperands() != 7)
     return nullptr;
 
   // Skip operand 0 which has been already parsed in the caller
   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(1)), "TotalSamples",
               TotalSamples))
     return nullptr;
   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(2)), "MaxSamplesPerLine",
               MaxSamplesPerLine))
     return nullptr;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(3)), "MaxHeadSamples",
-              MaxHeadSamples))
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(3)), "MaxFunctionCount",
+              MaxFunctionCount))
     return nullptr;
   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(4)), "NumLinesWithSamples",
               NumLinesWithSamples))
     return nullptr;
   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(5)), "NumFunctions",
               NumFunctions))
     return nullptr;
   if (!getSummaryFromMD(dyn_cast<MDTuple>(Tuple->getOperand(6)), Summary))
     return nullptr;
   return new SampleProfileSummary(TotalSamples, MaxSamplesPerLine,
-                                  MaxHeadSamples, NumLinesWithSamples,
+                                  MaxFunctionCount, NumLinesWithSamples,
                                   NumFunctions, Summary);
 }
 
 ProfileSummary *ProfileSummary::getFromMD(Metadata *MD) {
   if (!isa<MDTuple>(MD))
     return nullptr;
   MDTuple *Tuple = cast<MDTuple>(MD);
   auto &FormatMD = Tuple->getOperand(0);

lib/ProfileData/SampleProfWriter.cpp

std::error_code SampleProfileWriterBinary::writeHeader(
   }
   return sampleprof_error::success;
 }
 
 std::error_code SampleProfileWriterBinary::writeSummary() {
   auto &OS = *OutputStream;
   encodeULEB128(Summary->getTotalSamples(), OS);
   encodeULEB128(Summary->getMaxSamplesPerLine(), OS);
-  encodeULEB128(Summary->getMaxHeadSamples(), OS);
+  encodeULEB128(Summary->getMaxFunctionCount(), OS);
   encodeULEB128(Summary->getNumLinesWithSamples(), OS);
   encodeULEB128(Summary->getNumFunctions(), OS);
   std::vector<ProfileSummaryEntry> &Entries = Summary->getDetailedSummary();
   encodeULEB128(Entries.size(), OS);
   for (auto Entry : Entries) {
     encodeULEB128(Entry.Cutoff, OS);
     encodeULEB128(Entry.MinCount, OS);
     encodeULEB128(Entry.NumCounts, OS);

unittests/ProfileData/SampleProfTest.cpp

void testRoundTrip(SampleProfileFormat Format) {
     FunctionSamples &ReadBarSamples = ReadProfiles[BarName];
     ASSERT_EQ(20301u, ReadBarSamples.getTotalSamples());
     ASSERT_EQ(1437u, ReadBarSamples.getHeadSamples());
 
     auto VerifySummary = [](SampleProfileSummary &Summary) mutable {
       ASSERT_EQ(123603u, Summary.getTotalSamples());
       ASSERT_EQ(6u, Summary.getNumLinesWithSamples());
       ASSERT_EQ(2u, Summary.getNumFunctions());
-      ASSERT_EQ(1437u, Summary.getMaxHeadSamples());
+      ASSERT_EQ(1437u, Summary.getMaxFunctionCount());
       ASSERT_EQ(60351u, Summary.getMaxSamplesPerLine());
 
       uint32_t Cutoff = 800000;
       auto Predicate = [&Cutoff](const ProfileSummaryEntry &PE) {
         return PE.Cutoff == Cutoff;
       };
       std::vector<ProfileSummaryEntry> &Details = Summary.getDetailedSummary();
       auto EightyPerc = std::find_if(Details.begin(), Details.end(), Predicate);