804 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			804 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===- SampleProfReader.cpp - Read LLVM sample profile data ---------------===//
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| //
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| //                      The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This file implements the class that reads LLVM sample profiles. It
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| // supports three file formats: text, binary and gcov.
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| //
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| // The textual representation is useful for debugging and testing purposes. The
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| // binary representation is more compact, resulting in smaller file sizes.
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| //
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| // The gcov encoding is the one generated by GCC's AutoFDO profile creation
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| // tool (https://github.com/google/autofdo)
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| //
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| // All three encodings can be used interchangeably as an input sample profile.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "llvm/ProfileData/SampleProfReader.h"
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| #include "llvm/ADT/DenseMap.h"
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| #include "llvm/ADT/STLExtras.h"
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| #include "llvm/ADT/SmallVector.h"
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| #include "llvm/Support/Debug.h"
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| #include "llvm/Support/ErrorOr.h"
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| #include "llvm/Support/LEB128.h"
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| #include "llvm/Support/LineIterator.h"
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| #include "llvm/Support/MemoryBuffer.h"
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| 
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| using namespace llvm::sampleprof;
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| using namespace llvm;
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| 
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| /// \brief Dump the function profile for \p FName.
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| ///
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| /// \param FName Name of the function to print.
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| /// \param OS Stream to emit the output to.
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| void SampleProfileReader::dumpFunctionProfile(StringRef FName,
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|                                               raw_ostream &OS) {
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|   OS << "Function: " << FName << ": " << Profiles[FName];
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| }
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| 
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| /// \brief Dump all the function profiles found on stream \p OS.
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| void SampleProfileReader::dump(raw_ostream &OS) {
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|   for (const auto &I : Profiles)
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|     dumpFunctionProfile(I.getKey(), OS);
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| }
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| 
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| /// \brief Parse \p Input as function head.
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| ///
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| /// Parse one line of \p Input, and update function name in \p FName,
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| /// function's total sample count in \p NumSamples, function's entry
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| /// count in \p NumHeadSamples.
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| ///
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| /// \returns true if parsing is successful.
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| static bool ParseHead(const StringRef &Input, StringRef &FName,
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|                       uint64_t &NumSamples, uint64_t &NumHeadSamples) {
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|   if (Input[0] == ' ')
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|     return false;
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|   size_t n2 = Input.rfind(':');
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|   size_t n1 = Input.rfind(':', n2 - 1);
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|   FName = Input.substr(0, n1);
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|   if (Input.substr(n1 + 1, n2 - n1 - 1).getAsInteger(10, NumSamples))
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|     return false;
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|   if (Input.substr(n2 + 1).getAsInteger(10, NumHeadSamples))
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|     return false;
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|   return true;
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| }
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| 
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| /// \brief Returns true if line offset \p L is legal (only has 16 bits).
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| static bool isOffsetLegal(unsigned L) { return (L & 0xffff) == L; }
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| 
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| /// \brief Parse \p Input as line sample.
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| ///
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| /// \param Input input line.
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| /// \param IsCallsite true if the line represents an inlined callsite.
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| /// \param Depth the depth of the inline stack.
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| /// \param NumSamples total samples of the line/inlined callsite.
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| /// \param LineOffset line offset to the start of the function.
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| /// \param Discriminator discriminator of the line.
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| /// \param TargetCountMap map from indirect call target to count.
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| ///
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| /// returns true if parsing is successful.
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| static bool ParseLine(const StringRef &Input, bool &IsCallsite, uint32_t &Depth,
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|                       uint64_t &NumSamples, uint32_t &LineOffset,
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|                       uint32_t &Discriminator, StringRef &CalleeName,
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|                       DenseMap<StringRef, uint64_t> &TargetCountMap) {
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|   for (Depth = 0; Input[Depth] == ' '; Depth++)
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|     ;
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|   if (Depth == 0)
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|     return false;
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| 
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|   size_t n1 = Input.find(':');
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|   StringRef Loc = Input.substr(Depth, n1 - Depth);
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|   size_t n2 = Loc.find('.');
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|   if (n2 == StringRef::npos) {
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|     if (Loc.getAsInteger(10, LineOffset) || !isOffsetLegal(LineOffset))
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|       return false;
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|     Discriminator = 0;
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|   } else {
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|     if (Loc.substr(0, n2).getAsInteger(10, LineOffset))
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|       return false;
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|     if (Loc.substr(n2 + 1).getAsInteger(10, Discriminator))
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|       return false;
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|   }
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| 
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|   StringRef Rest = Input.substr(n1 + 2);
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|   if (Rest[0] >= '0' && Rest[0] <= '9') {
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|     IsCallsite = false;
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|     size_t n3 = Rest.find(' ');
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|     if (n3 == StringRef::npos) {
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|       if (Rest.getAsInteger(10, NumSamples))
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|         return false;
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|     } else {
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|       if (Rest.substr(0, n3).getAsInteger(10, NumSamples))
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|         return false;
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|     }
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|     while (n3 != StringRef::npos) {
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|       n3 += Rest.substr(n3).find_first_not_of(' ');
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|       Rest = Rest.substr(n3);
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|       n3 = Rest.find(' ');
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|       StringRef pair = Rest;
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|       if (n3 != StringRef::npos) {
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|         pair = Rest.substr(0, n3);
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|       }
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|       size_t n4 = pair.find(':');
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|       uint64_t count;
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|       if (pair.substr(n4 + 1).getAsInteger(10, count))
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|         return false;
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|       TargetCountMap[pair.substr(0, n4)] = count;
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|     }
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|   } else {
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|     IsCallsite = true;
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|     size_t n3 = Rest.find_last_of(':');
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|     CalleeName = Rest.substr(0, n3);
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|     if (Rest.substr(n3 + 1).getAsInteger(10, NumSamples))
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|       return false;
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|   }
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|   return true;
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| }
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| 
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| /// \brief Load samples from a text file.
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| ///
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| /// See the documentation at the top of the file for an explanation of
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| /// the expected format.
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| ///
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| /// \returns true if the file was loaded successfully, false otherwise.
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| std::error_code SampleProfileReaderText::read() {
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|   line_iterator LineIt(*Buffer, /*SkipBlanks=*/true, '#');
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|   sampleprof_error Result = sampleprof_error::success;
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| 
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|   InlineCallStack InlineStack;
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| 
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|   for (; !LineIt.is_at_eof(); ++LineIt) {
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|     if ((*LineIt)[(*LineIt).find_first_not_of(' ')] == '#')
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|       continue;
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|     // Read the header of each function.
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|     //
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|     // Note that for function identifiers we are actually expecting
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|     // mangled names, but we may not always get them. This happens when
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|     // the compiler decides not to emit the function (e.g., it was inlined
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|     // and removed). In this case, the binary will not have the linkage
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|     // name for the function, so the profiler will emit the function's
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|     // unmangled name, which may contain characters like ':' and '>' in its
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|     // name (member functions, templates, etc).
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|     //
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|     // The only requirement we place on the identifier, then, is that it
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|     // should not begin with a number.
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|     if ((*LineIt)[0] != ' ') {
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|       uint64_t NumSamples, NumHeadSamples;
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|       StringRef FName;
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|       if (!ParseHead(*LineIt, FName, NumSamples, NumHeadSamples)) {
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|         reportError(LineIt.line_number(),
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|                     "Expected 'mangled_name:NUM:NUM', found " + *LineIt);
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|         return sampleprof_error::malformed;
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|       }
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|       Profiles[FName] = FunctionSamples();
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|       FunctionSamples &FProfile = Profiles[FName];
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|       FProfile.setName(FName);
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|       MergeResult(Result, FProfile.addTotalSamples(NumSamples));
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|       MergeResult(Result, FProfile.addHeadSamples(NumHeadSamples));
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|       InlineStack.clear();
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|       InlineStack.push_back(&FProfile);
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|     } else {
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|       uint64_t NumSamples;
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|       StringRef FName;
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|       DenseMap<StringRef, uint64_t> TargetCountMap;
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|       bool IsCallsite;
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|       uint32_t Depth, LineOffset, Discriminator;
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|       if (!ParseLine(*LineIt, IsCallsite, Depth, NumSamples, LineOffset,
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|                      Discriminator, FName, TargetCountMap)) {
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|         reportError(LineIt.line_number(),
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|                     "Expected 'NUM[.NUM]: NUM[ mangled_name:NUM]*', found " +
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|                         *LineIt);
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|         return sampleprof_error::malformed;
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|       }
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|       if (IsCallsite) {
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|         while (InlineStack.size() > Depth) {
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|           InlineStack.pop_back();
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|         }
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|         FunctionSamples &FSamples = InlineStack.back()->functionSamplesAt(
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|             LineLocation(LineOffset, Discriminator));
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|         FSamples.setName(FName);
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|         MergeResult(Result, FSamples.addTotalSamples(NumSamples));
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|         InlineStack.push_back(&FSamples);
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|       } else {
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|         while (InlineStack.size() > Depth) {
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|           InlineStack.pop_back();
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|         }
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|         FunctionSamples &FProfile = *InlineStack.back();
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|         for (const auto &name_count : TargetCountMap) {
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|           MergeResult(Result, FProfile.addCalledTargetSamples(
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|                                   LineOffset, Discriminator, name_count.first,
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|                                   name_count.second));
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|         }
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|         MergeResult(Result, FProfile.addBodySamples(LineOffset, Discriminator,
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|                                                     NumSamples));
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|       }
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|     }
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|   }
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|   if (Result == sampleprof_error::success)
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|     computeSummary();
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| 
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|   return Result;
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| }
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| 
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| bool SampleProfileReaderText::hasFormat(const MemoryBuffer &Buffer) {
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|   bool result = false;
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| 
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|   // Check that the first non-comment line is a valid function header.
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|   line_iterator LineIt(Buffer, /*SkipBlanks=*/true, '#');
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|   if (!LineIt.is_at_eof()) {
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|     if ((*LineIt)[0] != ' ') {
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|       uint64_t NumSamples, NumHeadSamples;
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|       StringRef FName;
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|       result = ParseHead(*LineIt, FName, NumSamples, NumHeadSamples);
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|     }
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|   }
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| 
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|   return result;
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| }
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| 
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| template <typename T> ErrorOr<T> SampleProfileReaderBinary::readNumber() {
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|   unsigned NumBytesRead = 0;
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|   std::error_code EC;
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|   uint64_t Val = decodeULEB128(Data, &NumBytesRead);
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| 
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|   if (Val > std::numeric_limits<T>::max())
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|     EC = sampleprof_error::malformed;
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|   else if (Data + NumBytesRead > End)
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|     EC = sampleprof_error::truncated;
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|   else
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|     EC = sampleprof_error::success;
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| 
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|   if (EC) {
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|     reportError(0, EC.message());
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|     return EC;
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|   }
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| 
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|   Data += NumBytesRead;
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|   return static_cast<T>(Val);
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| }
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| 
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| ErrorOr<StringRef> SampleProfileReaderBinary::readString() {
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|   std::error_code EC;
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|   StringRef Str(reinterpret_cast<const char *>(Data));
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|   if (Data + Str.size() + 1 > End) {
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|     EC = sampleprof_error::truncated;
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|     reportError(0, EC.message());
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|     return EC;
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|   }
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| 
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|   Data += Str.size() + 1;
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|   return Str;
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| }
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| 
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| ErrorOr<StringRef> SampleProfileReaderBinary::readStringFromTable() {
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|   std::error_code EC;
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|   auto Idx = readNumber<uint32_t>();
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|   if (std::error_code EC = Idx.getError())
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|     return EC;
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|   if (*Idx >= NameTable.size())
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|     return sampleprof_error::truncated_name_table;
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|   return NameTable[*Idx];
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| }
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| 
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| std::error_code
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| SampleProfileReaderBinary::readProfile(FunctionSamples &FProfile) {
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|   auto NumSamples = readNumber<uint64_t>();
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|   if (std::error_code EC = NumSamples.getError())
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|     return EC;
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|   FProfile.addTotalSamples(*NumSamples);
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| 
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|   // Read the samples in the body.
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|   auto NumRecords = readNumber<uint32_t>();
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|   if (std::error_code EC = NumRecords.getError())
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|     return EC;
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| 
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|   for (uint32_t I = 0; I < *NumRecords; ++I) {
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|     auto LineOffset = readNumber<uint64_t>();
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|     if (std::error_code EC = LineOffset.getError())
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|       return EC;
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| 
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|     if (!isOffsetLegal(*LineOffset)) {
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|       return std::error_code();
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|     }
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| 
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|     auto Discriminator = readNumber<uint64_t>();
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|     if (std::error_code EC = Discriminator.getError())
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|       return EC;
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| 
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|     auto NumSamples = readNumber<uint64_t>();
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|     if (std::error_code EC = NumSamples.getError())
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|       return EC;
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| 
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|     auto NumCalls = readNumber<uint32_t>();
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|     if (std::error_code EC = NumCalls.getError())
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|       return EC;
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| 
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|     for (uint32_t J = 0; J < *NumCalls; ++J) {
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|       auto CalledFunction(readStringFromTable());
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|       if (std::error_code EC = CalledFunction.getError())
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|         return EC;
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| 
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|       auto CalledFunctionSamples = readNumber<uint64_t>();
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|       if (std::error_code EC = CalledFunctionSamples.getError())
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|         return EC;
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| 
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|       FProfile.addCalledTargetSamples(*LineOffset, *Discriminator,
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|                                       *CalledFunction, *CalledFunctionSamples);
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|     }
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| 
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|     FProfile.addBodySamples(*LineOffset, *Discriminator, *NumSamples);
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|   }
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| 
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|   // Read all the samples for inlined function calls.
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|   auto NumCallsites = readNumber<uint32_t>();
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|   if (std::error_code EC = NumCallsites.getError())
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|     return EC;
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| 
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|   for (uint32_t J = 0; J < *NumCallsites; ++J) {
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|     auto LineOffset = readNumber<uint64_t>();
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|     if (std::error_code EC = LineOffset.getError())
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|       return EC;
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| 
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|     auto Discriminator = readNumber<uint64_t>();
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|     if (std::error_code EC = Discriminator.getError())
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|       return EC;
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| 
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|     auto FName(readStringFromTable());
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|     if (std::error_code EC = FName.getError())
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|       return EC;
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| 
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|     FunctionSamples &CalleeProfile =
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|         FProfile.functionSamplesAt(LineLocation(*LineOffset, *Discriminator));
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|     CalleeProfile.setName(*FName);
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|     if (std::error_code EC = readProfile(CalleeProfile))
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|       return EC;
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|   }
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| 
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|   return sampleprof_error::success;
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| }
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| 
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| std::error_code SampleProfileReaderBinary::read() {
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|   while (!at_eof()) {
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|     auto NumHeadSamples = readNumber<uint64_t>();
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|     if (std::error_code EC = NumHeadSamples.getError())
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|       return EC;
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| 
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|     auto FName(readStringFromTable());
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|     if (std::error_code EC = FName.getError())
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|       return EC;
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| 
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|     Profiles[*FName] = FunctionSamples();
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|     FunctionSamples &FProfile = Profiles[*FName];
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|     FProfile.setName(*FName);
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| 
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|     FProfile.addHeadSamples(*NumHeadSamples);
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| 
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|     if (std::error_code EC = readProfile(FProfile))
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|       return EC;
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|   }
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| 
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|   return sampleprof_error::success;
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| }
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| 
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| std::error_code SampleProfileReaderBinary::readHeader() {
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|   Data = reinterpret_cast<const uint8_t *>(Buffer->getBufferStart());
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|   End = Data + Buffer->getBufferSize();
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| 
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|   // Read and check the magic identifier.
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|   auto Magic = readNumber<uint64_t>();
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|   if (std::error_code EC = Magic.getError())
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|     return EC;
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|   else if (*Magic != SPMagic())
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|     return sampleprof_error::bad_magic;
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| 
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|   // Read the version number.
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|   auto Version = readNumber<uint64_t>();
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|   if (std::error_code EC = Version.getError())
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|     return EC;
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|   else if (*Version != SPVersion())
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|     return sampleprof_error::unsupported_version;
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| 
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|   if (std::error_code EC = readSummary())
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|     return EC;
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| 
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|   // Read the name table.
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|   auto Size = readNumber<uint32_t>();
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|   if (std::error_code EC = Size.getError())
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|     return EC;
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|   NameTable.reserve(*Size);
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|   for (uint32_t I = 0; I < *Size; ++I) {
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|     auto Name(readString());
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|     if (std::error_code EC = Name.getError())
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|       return EC;
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|     NameTable.push_back(*Name);
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|   }
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| 
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|   return sampleprof_error::success;
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| }
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| 
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| std::error_code SampleProfileReaderBinary::readSummaryEntry(
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|     std::vector<ProfileSummaryEntry> &Entries) {
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|   auto Cutoff = readNumber<uint64_t>();
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|   if (std::error_code EC = Cutoff.getError())
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|     return EC;
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| 
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|   auto MinBlockCount = readNumber<uint64_t>();
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|   if (std::error_code EC = MinBlockCount.getError())
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|     return EC;
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| 
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|   auto NumBlocks = readNumber<uint64_t>();
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|   if (std::error_code EC = NumBlocks.getError())
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|     return EC;
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| 
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|   Entries.emplace_back(*Cutoff, *MinBlockCount, *NumBlocks);
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|   return sampleprof_error::success;
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| }
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| 
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| std::error_code SampleProfileReaderBinary::readSummary() {
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|   auto TotalCount = readNumber<uint64_t>();
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|   if (std::error_code EC = TotalCount.getError())
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|     return EC;
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| 
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|   auto MaxBlockCount = readNumber<uint64_t>();
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|   if (std::error_code EC = MaxBlockCount.getError())
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|     return EC;
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| 
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|   auto MaxFunctionCount = readNumber<uint64_t>();
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|   if (std::error_code EC = MaxFunctionCount.getError())
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|     return EC;
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| 
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|   auto NumBlocks = readNumber<uint64_t>();
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|   if (std::error_code EC = NumBlocks.getError())
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|     return EC;
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| 
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|   auto NumFunctions = readNumber<uint64_t>();
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|   if (std::error_code EC = NumFunctions.getError())
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|     return EC;
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| 
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|   auto NumSummaryEntries = readNumber<uint64_t>();
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|   if (std::error_code EC = NumSummaryEntries.getError())
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|     return EC;
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| 
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|   std::vector<ProfileSummaryEntry> Entries;
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|   for (unsigned i = 0; i < *NumSummaryEntries; i++) {
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|     std::error_code EC = readSummaryEntry(Entries);
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|     if (EC != sampleprof_error::success)
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|       return EC;
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|   }
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|   Summary = llvm::make_unique<SampleProfileSummary>(
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|       *TotalCount, *MaxBlockCount, *MaxFunctionCount, *NumBlocks, *NumFunctions,
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|       Entries);
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| 
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|   return sampleprof_error::success;
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| }
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| 
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| bool SampleProfileReaderBinary::hasFormat(const MemoryBuffer &Buffer) {
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|   const uint8_t *Data =
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|       reinterpret_cast<const uint8_t *>(Buffer.getBufferStart());
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|   uint64_t Magic = decodeULEB128(Data);
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|   return Magic == SPMagic();
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| }
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| 
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| std::error_code SampleProfileReaderGCC::skipNextWord() {
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|   uint32_t dummy;
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|   if (!GcovBuffer.readInt(dummy))
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|     return sampleprof_error::truncated;
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|   return sampleprof_error::success;
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| }
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| 
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| template <typename T> ErrorOr<T> SampleProfileReaderGCC::readNumber() {
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|   if (sizeof(T) <= sizeof(uint32_t)) {
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|     uint32_t Val;
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|     if (GcovBuffer.readInt(Val) && Val <= std::numeric_limits<T>::max())
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|       return static_cast<T>(Val);
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|   } else if (sizeof(T) <= sizeof(uint64_t)) {
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|     uint64_t Val;
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|     if (GcovBuffer.readInt64(Val) && Val <= std::numeric_limits<T>::max())
 | |
|       return static_cast<T>(Val);
 | |
|   }
 | |
| 
 | |
|   std::error_code EC = sampleprof_error::malformed;
 | |
|   reportError(0, EC.message());
 | |
|   return EC;
 | |
| }
 | |
| 
 | |
| ErrorOr<StringRef> SampleProfileReaderGCC::readString() {
 | |
|   StringRef Str;
 | |
|   if (!GcovBuffer.readString(Str))
 | |
|     return sampleprof_error::truncated;
 | |
|   return Str;
 | |
| }
 | |
| 
 | |
| std::error_code SampleProfileReaderGCC::readHeader() {
 | |
|   // Read the magic identifier.
 | |
|   if (!GcovBuffer.readGCDAFormat())
 | |
|     return sampleprof_error::unrecognized_format;
 | |
| 
 | |
|   // Read the version number. Note - the GCC reader does not validate this
 | |
|   // version, but the profile creator generates v704.
 | |
|   GCOV::GCOVVersion version;
 | |
|   if (!GcovBuffer.readGCOVVersion(version))
 | |
|     return sampleprof_error::unrecognized_format;
 | |
| 
 | |
|   if (version != GCOV::V704)
 | |
|     return sampleprof_error::unsupported_version;
 | |
| 
 | |
|   // Skip the empty integer.
 | |
|   if (std::error_code EC = skipNextWord())
 | |
|     return EC;
 | |
| 
 | |
|   return sampleprof_error::success;
 | |
| }
 | |
| 
 | |
| std::error_code SampleProfileReaderGCC::readSectionTag(uint32_t Expected) {
 | |
|   uint32_t Tag;
 | |
|   if (!GcovBuffer.readInt(Tag))
 | |
|     return sampleprof_error::truncated;
 | |
| 
 | |
|   if (Tag != Expected)
 | |
|     return sampleprof_error::malformed;
 | |
| 
 | |
|   if (std::error_code EC = skipNextWord())
 | |
|     return EC;
 | |
| 
 | |
|   return sampleprof_error::success;
 | |
| }
 | |
| 
 | |
| std::error_code SampleProfileReaderGCC::readNameTable() {
 | |
|   if (std::error_code EC = readSectionTag(GCOVTagAFDOFileNames))
 | |
|     return EC;
 | |
| 
 | |
|   uint32_t Size;
 | |
|   if (!GcovBuffer.readInt(Size))
 | |
|     return sampleprof_error::truncated;
 | |
| 
 | |
|   for (uint32_t I = 0; I < Size; ++I) {
 | |
|     StringRef Str;
 | |
|     if (!GcovBuffer.readString(Str))
 | |
|       return sampleprof_error::truncated;
 | |
|     Names.push_back(Str);
 | |
|   }
 | |
| 
 | |
|   return sampleprof_error::success;
 | |
| }
 | |
| 
 | |
| std::error_code SampleProfileReaderGCC::readFunctionProfiles() {
 | |
|   if (std::error_code EC = readSectionTag(GCOVTagAFDOFunction))
 | |
|     return EC;
 | |
| 
 | |
|   uint32_t NumFunctions;
 | |
|   if (!GcovBuffer.readInt(NumFunctions))
 | |
|     return sampleprof_error::truncated;
 | |
| 
 | |
|   InlineCallStack Stack;
 | |
|   for (uint32_t I = 0; I < NumFunctions; ++I)
 | |
|     if (std::error_code EC = readOneFunctionProfile(Stack, true, 0))
 | |
|       return EC;
 | |
| 
 | |
|   computeSummary();
 | |
|   return sampleprof_error::success;
 | |
| }
 | |
| 
 | |
| std::error_code SampleProfileReaderGCC::readOneFunctionProfile(
 | |
|     const InlineCallStack &InlineStack, bool Update, uint32_t Offset) {
 | |
|   uint64_t HeadCount = 0;
 | |
|   if (InlineStack.size() == 0)
 | |
|     if (!GcovBuffer.readInt64(HeadCount))
 | |
|       return sampleprof_error::truncated;
 | |
| 
 | |
|   uint32_t NameIdx;
 | |
|   if (!GcovBuffer.readInt(NameIdx))
 | |
|     return sampleprof_error::truncated;
 | |
| 
 | |
|   StringRef Name(Names[NameIdx]);
 | |
| 
 | |
|   uint32_t NumPosCounts;
 | |
|   if (!GcovBuffer.readInt(NumPosCounts))
 | |
|     return sampleprof_error::truncated;
 | |
| 
 | |
|   uint32_t NumCallsites;
 | |
|   if (!GcovBuffer.readInt(NumCallsites))
 | |
|     return sampleprof_error::truncated;
 | |
| 
 | |
|   FunctionSamples *FProfile = nullptr;
 | |
|   if (InlineStack.size() == 0) {
 | |
|     // If this is a top function that we have already processed, do not
 | |
|     // update its profile again.  This happens in the presence of
 | |
|     // function aliases.  Since these aliases share the same function
 | |
|     // body, there will be identical replicated profiles for the
 | |
|     // original function.  In this case, we simply not bother updating
 | |
|     // the profile of the original function.
 | |
|     FProfile = &Profiles[Name];
 | |
|     FProfile->addHeadSamples(HeadCount);
 | |
|     if (FProfile->getTotalSamples() > 0)
 | |
|       Update = false;
 | |
|   } else {
 | |
|     // Otherwise, we are reading an inlined instance. The top of the
 | |
|     // inline stack contains the profile of the caller. Insert this
 | |
|     // callee in the caller's CallsiteMap.
 | |
|     FunctionSamples *CallerProfile = InlineStack.front();
 | |
|     uint32_t LineOffset = Offset >> 16;
 | |
|     uint32_t Discriminator = Offset & 0xffff;
 | |
|     FProfile = &CallerProfile->functionSamplesAt(
 | |
|         LineLocation(LineOffset, Discriminator));
 | |
|   }
 | |
|   FProfile->setName(Name);
 | |
| 
 | |
|   for (uint32_t I = 0; I < NumPosCounts; ++I) {
 | |
|     uint32_t Offset;
 | |
|     if (!GcovBuffer.readInt(Offset))
 | |
|       return sampleprof_error::truncated;
 | |
| 
 | |
|     uint32_t NumTargets;
 | |
|     if (!GcovBuffer.readInt(NumTargets))
 | |
|       return sampleprof_error::truncated;
 | |
| 
 | |
|     uint64_t Count;
 | |
|     if (!GcovBuffer.readInt64(Count))
 | |
|       return sampleprof_error::truncated;
 | |
| 
 | |
|     // The line location is encoded in the offset as:
 | |
|     //   high 16 bits: line offset to the start of the function.
 | |
|     //   low 16 bits: discriminator.
 | |
|     uint32_t LineOffset = Offset >> 16;
 | |
|     uint32_t Discriminator = Offset & 0xffff;
 | |
| 
 | |
|     InlineCallStack NewStack;
 | |
|     NewStack.push_back(FProfile);
 | |
|     NewStack.insert(NewStack.end(), InlineStack.begin(), InlineStack.end());
 | |
|     if (Update) {
 | |
|       // Walk up the inline stack, adding the samples on this line to
 | |
|       // the total sample count of the callers in the chain.
 | |
|       for (auto CallerProfile : NewStack)
 | |
|         CallerProfile->addTotalSamples(Count);
 | |
| 
 | |
|       // Update the body samples for the current profile.
 | |
|       FProfile->addBodySamples(LineOffset, Discriminator, Count);
 | |
|     }
 | |
| 
 | |
|     // Process the list of functions called at an indirect call site.
 | |
|     // These are all the targets that a function pointer (or virtual
 | |
|     // function) resolved at runtime.
 | |
|     for (uint32_t J = 0; J < NumTargets; J++) {
 | |
|       uint32_t HistVal;
 | |
|       if (!GcovBuffer.readInt(HistVal))
 | |
|         return sampleprof_error::truncated;
 | |
| 
 | |
|       if (HistVal != HIST_TYPE_INDIR_CALL_TOPN)
 | |
|         return sampleprof_error::malformed;
 | |
| 
 | |
|       uint64_t TargetIdx;
 | |
|       if (!GcovBuffer.readInt64(TargetIdx))
 | |
|         return sampleprof_error::truncated;
 | |
|       StringRef TargetName(Names[TargetIdx]);
 | |
| 
 | |
|       uint64_t TargetCount;
 | |
|       if (!GcovBuffer.readInt64(TargetCount))
 | |
|         return sampleprof_error::truncated;
 | |
| 
 | |
|       if (Update) {
 | |
|         FunctionSamples &TargetProfile = Profiles[TargetName];
 | |
|         TargetProfile.addCalledTargetSamples(LineOffset, Discriminator,
 | |
|                                              TargetName, TargetCount);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   // Process all the inlined callers into the current function. These
 | |
|   // are all the callsites that were inlined into this function.
 | |
|   for (uint32_t I = 0; I < NumCallsites; I++) {
 | |
|     // The offset is encoded as:
 | |
|     //   high 16 bits: line offset to the start of the function.
 | |
|     //   low 16 bits: discriminator.
 | |
|     uint32_t Offset;
 | |
|     if (!GcovBuffer.readInt(Offset))
 | |
|       return sampleprof_error::truncated;
 | |
|     InlineCallStack NewStack;
 | |
|     NewStack.push_back(FProfile);
 | |
|     NewStack.insert(NewStack.end(), InlineStack.begin(), InlineStack.end());
 | |
|     if (std::error_code EC = readOneFunctionProfile(NewStack, Update, Offset))
 | |
|       return EC;
 | |
|   }
 | |
| 
 | |
|   return sampleprof_error::success;
 | |
| }
 | |
| 
 | |
| /// \brief Read a GCC AutoFDO profile.
 | |
| ///
 | |
| /// This format is generated by the Linux Perf conversion tool at
 | |
| /// https://github.com/google/autofdo.
 | |
| std::error_code SampleProfileReaderGCC::read() {
 | |
|   // Read the string table.
 | |
|   if (std::error_code EC = readNameTable())
 | |
|     return EC;
 | |
| 
 | |
|   // Read the source profile.
 | |
|   if (std::error_code EC = readFunctionProfiles())
 | |
|     return EC;
 | |
| 
 | |
|   return sampleprof_error::success;
 | |
| }
 | |
| 
 | |
| bool SampleProfileReaderGCC::hasFormat(const MemoryBuffer &Buffer) {
 | |
|   StringRef Magic(reinterpret_cast<const char *>(Buffer.getBufferStart()));
 | |
|   return Magic == "adcg*704";
 | |
| }
 | |
| 
 | |
| /// \brief Prepare a memory buffer for the contents of \p Filename.
 | |
| ///
 | |
| /// \returns an error code indicating the status of the buffer.
 | |
| static ErrorOr<std::unique_ptr<MemoryBuffer>>
 | |
| setupMemoryBuffer(std::string Filename) {
 | |
|   auto BufferOrErr = MemoryBuffer::getFileOrSTDIN(Filename);
 | |
|   if (std::error_code EC = BufferOrErr.getError())
 | |
|     return EC;
 | |
|   auto Buffer = std::move(BufferOrErr.get());
 | |
| 
 | |
|   // Sanity check the file.
 | |
|   if (Buffer->getBufferSize() > std::numeric_limits<uint32_t>::max())
 | |
|     return sampleprof_error::too_large;
 | |
| 
 | |
|   return std::move(Buffer);
 | |
| }
 | |
| 
 | |
| /// \brief Create a sample profile reader based on the format of the input file.
 | |
| ///
 | |
| /// \param Filename The file to open.
 | |
| ///
 | |
| /// \param Reader The reader to instantiate according to \p Filename's format.
 | |
| ///
 | |
| /// \param C The LLVM context to use to emit diagnostics.
 | |
| ///
 | |
| /// \returns an error code indicating the status of the created reader.
 | |
| ErrorOr<std::unique_ptr<SampleProfileReader>>
 | |
| SampleProfileReader::create(StringRef Filename, LLVMContext &C) {
 | |
|   auto BufferOrError = setupMemoryBuffer(Filename);
 | |
|   if (std::error_code EC = BufferOrError.getError())
 | |
|     return EC;
 | |
|   return create(BufferOrError.get(), C);
 | |
| }
 | |
| 
 | |
| /// \brief Create a sample profile reader based on the format of the input data.
 | |
| ///
 | |
| /// \param B The memory buffer to create the reader from (assumes ownership).
 | |
| ///
 | |
| /// \param Reader The reader to instantiate according to \p Filename's format.
 | |
| ///
 | |
| /// \param C The LLVM context to use to emit diagnostics.
 | |
| ///
 | |
| /// \returns an error code indicating the status of the created reader.
 | |
| ErrorOr<std::unique_ptr<SampleProfileReader>>
 | |
| SampleProfileReader::create(std::unique_ptr<MemoryBuffer> &B, LLVMContext &C) {
 | |
|   std::unique_ptr<SampleProfileReader> Reader;
 | |
|   if (SampleProfileReaderBinary::hasFormat(*B))
 | |
|     Reader.reset(new SampleProfileReaderBinary(std::move(B), C));
 | |
|   else if (SampleProfileReaderGCC::hasFormat(*B))
 | |
|     Reader.reset(new SampleProfileReaderGCC(std::move(B), C));
 | |
|   else if (SampleProfileReaderText::hasFormat(*B))
 | |
|     Reader.reset(new SampleProfileReaderText(std::move(B), C));
 | |
|   else
 | |
|     return sampleprof_error::unrecognized_format;
 | |
| 
 | |
|   if (std::error_code EC = Reader->readHeader())
 | |
|     return EC;
 | |
| 
 | |
|   return std::move(Reader);
 | |
| }
 | |
| 
 | |
| // For text and GCC file formats, we compute the summary after reading the
 | |
| // profile. Binary format has the profile summary in its header.
 | |
| void SampleProfileReader::computeSummary() {
 | |
|   Summary.reset(new SampleProfileSummary(ProfileSummary::DefaultCutoffs));
 | |
|   for (const auto &I : Profiles) {
 | |
|     const FunctionSamples &Profile = I.second;
 | |
|     Summary->addRecord(Profile);
 | |
|   }
 | |
|   Summary->computeDetailedSummary();
 | |
| }
 |