[nfc]Make InstrProfSymtab non-copyable and non-movable (#86882)

- The direct use case (in [1]) is to add `llvm::IntervalMap` [2]  and the allocator required by IntervalMap ctor [3]
   to class `InstrProfSymtab` as owned members. The allocator class doesn't have a move-assignment operator; 
   and it's going to take much effort to implement move-assignment operator for the allocator class such that the
   enclosing class is movable.
- There is only one use of compiler-generated move-assignment operator in the repo, which is in 
   CoverageMappingReader.cpp. Luckily it's possible to use std::unique_ptr<InstrProfSymtab> instead, so did the change.

[1] #66825
[2] https://github.com/llvm/llvm-project/blob/4c2f68840e984b0f111779c46845ac00e3a7547d/llvm/include/llvm/ADT/IntervalMap.h#L936
[3] https://github.com/llvm/llvm-project/blob/4c2f68840e984b0f111779c46845ac00e3a7547d/llvm/include/llvm/ADT/IntervalMap.h#L1041

Author: mingmingl-llvm

llvm/include/llvm/ProfileData/Coverage/CoverageMappingReader.h

@@ -184,7 +184,7 @@ class BinaryCoverageReader : public CoverageMappingReader {
 private:
   std::vector<std::string> Filenames;
   std::vector<ProfileMappingRecord> MappingRecords;
-  InstrProfSymtab ProfileNames;
+  std::unique_ptr<InstrProfSymtab> ProfileNames;
   size_t CurrentRecord = 0;
   std::vector<StringRef> FunctionsFilenames;
   std::vector<CounterExpression> Expressions;
@@ -195,8 +195,9 @@ class BinaryCoverageReader : public CoverageMappingReader {
   // D69471, which can split up function records into multiple sections on ELF.
   FuncRecordsStorage FuncRecords;
 
-  BinaryCoverageReader(FuncRecordsStorage &&FuncRecords)
-      : FuncRecords(std::move(FuncRecords)) {}
+  BinaryCoverageReader(std::unique_ptr<InstrProfSymtab> Symtab,
+                       FuncRecordsStorage &&FuncRecords)
+      : ProfileNames(std::move(Symtab)), FuncRecords(std::move(FuncRecords)) {}
 
 public:
   BinaryCoverageReader(const BinaryCoverageReader &) = delete;
@@ -209,12 +210,10 @@ class BinaryCoverageReader : public CoverageMappingReader {
          SmallVectorImpl<object::BuildIDRef> *BinaryIDs = nullptr);
 
   static Expected<std::unique_ptr<BinaryCoverageReader>>
-  createCoverageReaderFromBuffer(StringRef Coverage,
-                                 FuncRecordsStorage &&FuncRecords,
-                                 InstrProfSymtab &&ProfileNames,
-                                 uint8_t BytesInAddress,
-                                 llvm::endianness Endian,
-                                 StringRef CompilationDir = "");
+  createCoverageReaderFromBuffer(
+      StringRef Coverage, FuncRecordsStorage &&FuncRecords,
+      std::unique_ptr<InstrProfSymtab> ProfileNamesPtr, uint8_t BytesInAddress,
+      llvm::endianness Endian, StringRef CompilationDir = "");
 
   Error readNextRecord(CoverageMappingRecord &Record) override;
 };

llvm/include/llvm/ProfileData/InstrProf.h

@@ -471,6 +471,13 @@ class InstrProfSymtab {
 public:
   InstrProfSymtab() = default;
 
+  // Not copyable or movable.
+  // Consider std::unique_ptr for move.
+  InstrProfSymtab(const InstrProfSymtab &) = delete;
+  InstrProfSymtab &operator=(const InstrProfSymtab &) = delete;
+  InstrProfSymtab(InstrProfSymtab &&) = delete;
+  InstrProfSymtab &operator=(InstrProfSymtab &&) = delete;
+
   /// Create InstrProfSymtab from an object file section which
   /// contains function PGO names. When section may contain raw
   /// string data or string data in compressed form. This method

llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp

@@ -894,31 +894,34 @@ static Error readCoverageMappingData(
 Expected<std::unique_ptr<BinaryCoverageReader>>
 BinaryCoverageReader::createCoverageReaderFromBuffer(
     StringRef Coverage, FuncRecordsStorage &&FuncRecords,
-    InstrProfSymtab &&ProfileNames, uint8_t BytesInAddress,
+    std::unique_ptr<InstrProfSymtab> ProfileNamesPtr, uint8_t BytesInAddress,
     llvm::endianness Endian, StringRef CompilationDir) {
-  std::unique_ptr<BinaryCoverageReader> Reader(
-      new BinaryCoverageReader(std::move(FuncRecords)));
-  Reader->ProfileNames = std::move(ProfileNames);
+  if (ProfileNamesPtr == nullptr)
+    return make_error<CoverageMapError>(coveragemap_error::malformed,
+                                        "Caller must provide ProfileNames");
+  std::unique_ptr<BinaryCoverageReader> Reader(new BinaryCoverageReader(
+      std::move(ProfileNamesPtr), std::move(FuncRecords)));
+  InstrProfSymtab &ProfileNames = *Reader->ProfileNames;
   StringRef FuncRecordsRef = Reader->FuncRecords->getBuffer();
   if (BytesInAddress == 4 && Endian == llvm::endianness::little) {
     if (Error E = readCoverageMappingData<uint32_t, llvm::endianness::little>(
-            Reader->ProfileNames, Coverage, FuncRecordsRef,
-            Reader->MappingRecords, CompilationDir, Reader->Filenames))
+            ProfileNames, Coverage, FuncRecordsRef, Reader->MappingRecords,
+            CompilationDir, Reader->Filenames))
       return std::move(E);
   } else if (BytesInAddress == 4 && Endian == llvm::endianness::big) {
     if (Error E = readCoverageMappingData<uint32_t, llvm::endianness::big>(
-            Reader->ProfileNames, Coverage, FuncRecordsRef,
-            Reader->MappingRecords, CompilationDir, Reader->Filenames))
+            ProfileNames, Coverage, FuncRecordsRef, Reader->MappingRecords,
+            CompilationDir, Reader->Filenames))
       return std::move(E);
   } else if (BytesInAddress == 8 && Endian == llvm::endianness::little) {
     if (Error E = readCoverageMappingData<uint64_t, llvm::endianness::little>(
-            Reader->ProfileNames, Coverage, FuncRecordsRef,
-            Reader->MappingRecords, CompilationDir, Reader->Filenames))
+            ProfileNames, Coverage, FuncRecordsRef, Reader->MappingRecords,
+            CompilationDir, Reader->Filenames))
       return std::move(E);
   } else if (BytesInAddress == 8 && Endian == llvm::endianness::big) {
     if (Error E = readCoverageMappingData<uint64_t, llvm::endianness::big>(
-            Reader->ProfileNames, Coverage, FuncRecordsRef,
-            Reader->MappingRecords, CompilationDir, Reader->Filenames))
+            ProfileNames, Coverage, FuncRecordsRef, Reader->MappingRecords,
+            CompilationDir, Reader->Filenames))
       return std::move(E);
   } else
     return make_error<CoverageMapError>(
@@ -963,8 +966,8 @@ loadTestingFormat(StringRef Data, StringRef CompilationDir) {
   if (Data.size() < ProfileNamesSize)
     return make_error<CoverageMapError>(coveragemap_error::malformed,
                                         "the size of ProfileNames is too big");
-  InstrProfSymtab ProfileNames;
-  if (Error E = ProfileNames.create(Data.substr(0, ProfileNamesSize), Address))
+  auto ProfileNames = std::make_unique<InstrProfSymtab>();
+  if (Error E = ProfileNames->create(Data.substr(0, ProfileNamesSize), Address))
     return std::move(E);
   Data = Data.substr(ProfileNamesSize);
 
@@ -1099,7 +1102,7 @@ loadBinaryFormat(std::unique_ptr<Binary> Bin, StringRef Arch,
       OF->isLittleEndian() ? llvm::endianness::little : llvm::endianness::big;
 
   // Look for the sections that we are interested in.
-  InstrProfSymtab ProfileNames;
+  auto ProfileNames = std::make_unique<InstrProfSymtab>();
   std::vector<SectionRef> NamesSectionRefs;
   // If IPSK_name is not found, fallback to search for IPK_covname, which is
   // used when binary correlation is enabled.
@@ -1116,7 +1119,7 @@ loadBinaryFormat(std::unique_ptr<Binary> Bin, StringRef Arch,
     return make_error<CoverageMapError>(
         coveragemap_error::malformed,
         "the size of coverage mapping section is not one");
-  if (Error E = ProfileNames.create(NamesSectionRefs.back()))
+  if (Error E = ProfileNames->create(NamesSectionRefs.back()))
     return std::move(E);
 
   auto CoverageSection = lookupSections(*OF, IPSK_covmap);