[Debuginfo][NFC] Rename error handling functions using the same pattern.

[avl]

Summary

That patch is extracted from https://reviews.llvm.org/D74308.
Currently there are two patterns to name error handling functions:
using "Callback" and "Handler". This patch uses "Handler" for all
usage places.

[dblaikie]

Looks good - thanks!

[jhenderson]

LGTM too.

llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h

public:
   /// Get a reference to the parsed accelerator table object.
   const AppleAcceleratorTable &getAppleObjC();
 
   /// Get a pointer to a parsed line table corresponding to a compile unit.
   /// Report any parsing issues as warnings on stderr.
   const DWARFDebugLine::LineTable *getLineTableForUnit(DWARFUnit *U);
 
   /// Get a pointer to a parsed line table corresponding to a compile unit.
-  /// Report any recoverable parsing problems using the callback.
+  /// Report any recoverable parsing problems using the handler.
   Expected<const DWARFDebugLine::LineTable *>
   getLineTableForUnit(DWARFUnit *U,
-                      function_ref<void(Error)> RecoverableErrorCallback);
+                      function_ref<void(Error)> RecoverableErrorHandler);
 
   DataExtractor getStringExtractor() const {
     return DataExtractor(DObj->getStrSection(), false, 0);
   }
   DataExtractor getLineStringExtractor() const {
     return DataExtractor(DObj->getLineStrSection(), false, 0);
   }
 

llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h

struct Prologue {
     getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
                        DILineInfoSpecifier::FileLineInfoKind Kind,
                        std::string &Result,
                        sys::path::Style Style = sys::path::Style::native) const;
 
     void clear();
     void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
     Error parse(const DWARFDataExtractor &DebugLineData, uint64_t *OffsetPtr,
-                function_ref<void(Error)> RecoverableErrorCallback,
+                function_ref<void(Error)> RecoverableErrorHandler,
                 const DWARFContext &Ctx, const DWARFUnit *U = nullptr);
   };
 
   /// Standard .debug_line state machine structure.
   struct Row {
     explicit Row(bool DefaultIsStmt = false);
 
     /// Called after a row is appended to the matrix.
bool getFileLineInfoForAddress(object::SectionedAddress Address,
                                    DILineInfo &Result) const;
 
     void dump(raw_ostream &OS, DIDumpOptions DumpOptions) const;
     void clear();
 
     /// Parse prologue and all rows.
     Error parse(DWARFDataExtractor &DebugLineData, uint64_t *OffsetPtr,
                 const DWARFContext &Ctx, const DWARFUnit *U,
-                function_ref<void(Error)> RecoverableErrorCallback,
+                function_ref<void(Error)> RecoverableErrorHandler,
                 raw_ostream *OS = nullptr);
 
     using RowVector = std::vector<Row>;
     using RowIter = RowVector::const_iterator;
     using SequenceVector = std::vector<Sequence>;
     using SequenceIter = SequenceVector::const_iterator;
 
     struct Prologue Prologue;
private:
     bool lookupAddressRangeImpl(object::SectionedAddress Address, uint64_t Size,
                                 std::vector<uint32_t> &Result) const;
   };
 
   const LineTable *getLineTable(uint64_t Offset) const;
   Expected<const LineTable *>
   getOrParseLineTable(DWARFDataExtractor &DebugLineData, uint64_t Offset,
                       const DWARFContext &Ctx, const DWARFUnit *U,
-                      function_ref<void(Error)> RecoverableErrorCallback);
+                      function_ref<void(Error)> RecoverableErrorHandler);
 
   /// Helper to allow for parsing of an entire .debug_line section in sequence.
   class SectionParser {
   public:
     using cu_range = DWARFUnitVector::iterator_range;
     using tu_range = DWARFUnitVector::iterator_range;
     using LineToUnitMap = std::map<uint64_t, DWARFUnit *>;
 
     SectionParser(DWARFDataExtractor &Data, const DWARFContext &C, cu_range CUs,
                   tu_range TUs);
 
     /// Get the next line table from the section. Report any issues via the
-    /// callbacks.
+    /// handlers.
     ///
-    /// \param RecoverableErrorCallback - any issues that don't prevent further
-    /// parsing of the table will be reported through this callback.
-    /// \param UnrecoverableErrorCallback - any issues that prevent further
-    /// parsing of the table will be reported through this callback.
+    /// \param RecoverableErrorHandler - any issues that don't prevent further
+    /// parsing of the table will be reported through this handler.
+    /// \param UnrecoverableErrorHandler - any issues that prevent further
+    /// parsing of the table will be reported through this handler.
     /// \param OS - if not null, the parser will print information about the
     /// table as it parses it.
     LineTable
     parseNext(
-        function_ref<void(Error)> RecoverableErrorCallback,
-        function_ref<void(Error)> UnrecoverableErrorCallback,
+        function_ref<void(Error)> RecoverableErrorHandler,
+        function_ref<void(Error)> UnrecoverableErrorHandler,
         raw_ostream *OS = nullptr);
 
     /// Skip the current line table and go to the following line table (if
     /// present) immediately.
     ///
-    /// \param RecoverableErrorCallback - report any recoverable prologue
-    /// parsing issues via this callback.
-    /// \param UnrecoverableErrorCallback - report any unrecoverable prologue
-    /// parsing issues via this callback.
-    void skip(function_ref<void(Error)> RecoverableErrorCallback,
-              function_ref<void(Error)> UnrecoverableErrorCallback);
+    /// \param RecoverableErrorHandler - report any recoverable prologue
+    /// parsing issues via this handler.
+    /// \param UnrecoverableErrorHandler - report any unrecoverable prologue
+    /// parsing issues via this handler.
+    void skip(function_ref<void(Error)> RecoverableErrorHandler,
+              function_ref<void(Error)> UnrecoverableErrorHandler);
 
     /// Indicates if the parser has parsed as much as possible.
     ///
     /// \note Certain problems with the line table structure might mean that
     /// parsing stops before the end of the section is reached.
     bool done() const { return Done; }
 
     /// Get the offset the parser has reached.

llvm/lib/DebugInfo/DWARF/DWARFContext.cpp

DWARFContext::getLineTableForUnit(DWARFUnit *U) {
   if (!ExpectedLineTable) {
     dumpWarning(ExpectedLineTable.takeError());
     return nullptr;
   }
   return *ExpectedLineTable;
 }
 
 Expected<const DWARFDebugLine::LineTable *> DWARFContext::getLineTableForUnit(
-    DWARFUnit *U, function_ref<void(Error)> RecoverableErrorCallback) {
+    DWARFUnit *U, function_ref<void(Error)> RecoverableErrorHandler) {
   if (!Line)
     Line.reset(new DWARFDebugLine);
 
   auto UnitDIE = U->getUnitDIE();
   if (!UnitDIE)
     return nullptr;
 
   auto Offset = toSectionOffset(UnitDIE.find(DW_AT_stmt_list));
   if (!Offset)
     return nullptr; // No line table for this compile unit.
 
   uint64_t stmtOffset = *Offset + U->getLineTableOffset();
   // See if the line table is cached.
   if (const DWARFLineTable *lt = Line->getLineTable(stmtOffset))
     return lt;
 
   // Make sure the offset is good before we try to parse.
   if (stmtOffset >= U->getLineSection().Data.size())
     return nullptr;
 
   // We have to parse it first.
   DWARFDataExtractor lineData(*DObj, U->getLineSection(), isLittleEndian(),
                               U->getAddressByteSize());
   return Line->getOrParseLineTable(lineData, stmtOffset, *this, U,
-                                   RecoverableErrorCallback);
+                                   RecoverableErrorHandler);
 }
 
 void DWARFContext::parseNormalUnits() {
   if (!NormalUnits.empty())
     return;
   DObj->forEachInfoSections([&](const DWARFSection &S) {
     NormalUnits.addUnitsForSection(*this, S, DW_SECT_INFO);
   });

llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp

uint64_t Length = PrologueLength + sizeofTotalLength() +
                     sizeof(getVersion()) + sizeofPrologueLength();
   if (getVersion() >= 5)
     Length += 2; // Address + Segment selector sizes.
   return Length;
 }
 
 Error DWARFDebugLine::Prologue::parse(
     const DWARFDataExtractor &DebugLineData, uint64_t *OffsetPtr,
-    function_ref<void(Error)> RecoverableErrorCallback, const DWARFContext &Ctx,
+    function_ref<void(Error)> RecoverableErrorHandler, const DWARFContext &Ctx,
     const DWARFUnit *U) {
   const uint64_t PrologueOffset = *OffsetPtr;
 
   clear();
   TotalLength = DebugLineData.getRelocatedValue(4, OffsetPtr);
   if (TotalLength == dwarf::DW_LENGTH_DWARF64) {
     FormParams.Format = dwarf::DWARF64;
     TotalLength = DebugLineData.getU64(OffsetPtr);
for (uint32_t I = 1; I < OpcodeBase; ++I) {
     uint8_t OpLen = DebugLineData.getU8(OffsetPtr);
     StandardOpcodeLengths.push_back(OpLen);
   }
 
   if (getVersion() >= 5) {
     if (Error E =
             parseV5DirFileTables(DebugLineData, OffsetPtr, FormParams, Ctx, U,
                                  ContentTypes, IncludeDirectories, FileNames)) {
-      RecoverableErrorCallback(joinErrors(
+      RecoverableErrorHandler(joinErrors(
           createStringError(
               errc::invalid_argument,
               "parsing line table prologue at 0x%8.8" PRIx64
               " found an invalid directory or file table description at"
               " 0x%8.8" PRIx64,
               PrologueOffset, *OffsetPtr),
           std::move(E)));
       // Skip to the end of the prologue, since the chances are that the parser
       // did not read the whole table. This prevents the length check below from
       // executing.
       if (*OffsetPtr < EndPrologueOffset)
         *OffsetPtr = EndPrologueOffset;
     }
   } else
     parseV2DirFileTables(DebugLineData, OffsetPtr, EndPrologueOffset,
                          ContentTypes, IncludeDirectories, FileNames);
 
   if (*OffsetPtr != EndPrologueOffset) {
-    RecoverableErrorCallback(createStringError(
+    RecoverableErrorHandler(createStringError(
         errc::invalid_argument,
         "parsing line table prologue at 0x%8.8" PRIx64
         " should have ended at 0x%8.8" PRIx64 " but it ended at 0x%8.8" PRIx64,
         PrologueOffset, EndPrologueOffset, *OffsetPtr));
     *OffsetPtr = EndPrologueOffset;
   }
   return Error::success();
 }
DWARFDebugLine::getLineTable(uint64_t Offset) const {
   LineTableConstIter Pos = LineTableMap.find(Offset);
   if (Pos != LineTableMap.end())
     return &Pos->second;
   return nullptr;
 }
 
 Expected<const DWARFDebugLine::LineTable *> DWARFDebugLine::getOrParseLineTable(
     DWARFDataExtractor &DebugLineData, uint64_t Offset, const DWARFContext &Ctx,
-    const DWARFUnit *U, function_ref<void(Error)> RecoverableErrorCallback) {
+    const DWARFUnit *U, function_ref<void(Error)> RecoverableErrorHandler) {
   if (!DebugLineData.isValidOffset(Offset))
     return createStringError(errc::invalid_argument, "offset 0x%8.8" PRIx64
                        " is not a valid debug line section offset",
                        Offset);
 
   std::pair<LineTableIter, bool> Pos =
       LineTableMap.insert(LineTableMapTy::value_type(Offset, LineTable()));
   LineTable *LT = &Pos.first->second;
   if (Pos.second) {
     if (Error Err =
-            LT->parse(DebugLineData, &Offset, Ctx, U, RecoverableErrorCallback))
+            LT->parse(DebugLineData, &Offset, Ctx, U, RecoverableErrorHandler))
       return std::move(Err);
     return LT;
   }
   return LT;
 }
 
 Error DWARFDebugLine::LineTable::parse(
     DWARFDataExtractor &DebugLineData, uint64_t *OffsetPtr,
     const DWARFContext &Ctx, const DWARFUnit *U,
-    function_ref<void(Error)> RecoverableErrorCallback, raw_ostream *OS) {
+    function_ref<void(Error)> RecoverableErrorHandler, raw_ostream *OS) {
   const uint64_t DebugLineOffset = *OffsetPtr;
 
   clear();
 
   Error PrologueErr = Prologue.parse(DebugLineData, OffsetPtr,
-                                     RecoverableErrorCallback, Ctx, U);
+                                     RecoverableErrorHandler, Ctx, U);
 
   if (OS) {
     // The presence of OS signals verbose dumping.
     DIDumpOptions DumpOptions;
     DumpOptions.Verbose = true;
     Prologue.dump(*OS, DumpOptions);
   }
 
   if (PrologueErr)
     return PrologueErr;
 
   uint64_t ProgramLength = Prologue.TotalLength + Prologue.sizeofTotalLength();
   if (!DebugLineData.isValidOffsetForDataOfSize(DebugLineOffset,
                                                 ProgramLength)) {
     assert(DebugLineData.size() > DebugLineOffset &&
            "prologue parsing should handle invalid offset");
     uint64_t BytesRemaining = DebugLineData.size() - DebugLineOffset;
-    RecoverableErrorCallback(
+    RecoverableErrorHandler(
         createStringError(errc::invalid_argument,
                           "line table program with offset 0x%8.8" PRIx64
                           " has length 0x%8.8" PRIx64 " but only 0x%8.8" PRIx64
                           " bytes are available",
                           DebugLineOffset, ProgramLength, BytesRemaining));
     // Continue by capping the length at the number of remaining bytes.
     ProgramLength = BytesRemaining;
   }
if (Opcode == 0) {
         // that affect the address register add a delta to it. This instruction
         // stores a relocatable value into it instead.
         //
         // Make sure the extractor knows the address size.  If not, infer it
         // from the size of the operand.
         {
           uint8_t ExtractorAddressSize = DebugLineData.getAddressSize();
           if (ExtractorAddressSize != Len - 1 && ExtractorAddressSize != 0)
-            RecoverableErrorCallback(createStringError(
+            RecoverableErrorHandler(createStringError(
                 errc::invalid_argument,
                 "mismatching address size at offset 0x%8.8" PRIx64
                 " expected 0x%2.2" PRIx8 " found 0x%2.2" PRIx64,
                 ExtOffset, ExtractorAddressSize, Len - 1));
 
           // Assume that the line table is correct and temporarily override the
           // address size.
           DebugLineData.setAddressSize(Len - 1);
if (Opcode == 0) {
         (*OffsetPtr) += Len - 1;
         break;
       }
       // Make sure the length as recorded in the table and the standard length
       // for the opcode match. If they don't, continue from the end as claimed
       // by the table.
       uint64_t End = ExtOffset + Len;
       if (*OffsetPtr != End) {
-        RecoverableErrorCallback(createStringError(
+        RecoverableErrorHandler(createStringError(
             errc::illegal_byte_sequence,
             "unexpected line op length at offset 0x%8.8" PRIx64
             " expected 0x%2.2" PRIx64 " found 0x%2.2" PRIx64,
             ExtOffset, Len, *OffsetPtr - ExtOffset));
         *OffsetPtr = End;
       }
     } else if (Opcode < Prologue.OpcodeBase) {
       if (OS)
if (Opcode == 0) {
 
       State.appendRowToMatrix();
     }
     if(OS)
       *OS << "\n";
   }
 
   if (!State.Sequence.Empty)
-    RecoverableErrorCallback(createStringError(
+    RecoverableErrorHandler(createStringError(
         errc::illegal_byte_sequence,
         "last sequence in debug line table at offset 0x%8.8" PRIx64
         " is not terminated",
         DebugLineOffset));
 
   // Sort all sequences so that address lookup will work faster.
   if (!Sequences.empty()) {
     llvm::sort(Sequences, Sequence::orderByHighPC);

 }
 
 bool DWARFDebugLine::Prologue::totalLengthIsValid() const {
   return TotalLength == dwarf::DW_LENGTH_DWARF64 ||
          TotalLength < dwarf::DW_LENGTH_lo_reserved;
 }
 
 DWARFDebugLine::LineTable DWARFDebugLine::SectionParser::parseNext(
-    function_ref<void(Error)> RecoverableErrorCallback,
-    function_ref<void(Error)> UnrecoverableErrorCallback, raw_ostream *OS) {
+    function_ref<void(Error)> RecoverableErrorHandler,
+    function_ref<void(Error)> UnrecoverableErrorHandler, raw_ostream *OS) {
   assert(DebugLineData.isValidOffset(Offset) &&
          "parsing should have terminated");
   DWARFUnit *U = prepareToParse(Offset);
   uint64_t OldOffset = Offset;
   LineTable LT;
   if (Error Err = LT.parse(DebugLineData, &Offset, Context, U,
-                           RecoverableErrorCallback, OS))
-    UnrecoverableErrorCallback(std::move(Err));
+                           RecoverableErrorHandler, OS))
+    UnrecoverableErrorHandler(std::move(Err));
   moveToNextTable(OldOffset, LT.Prologue);
   return LT;
 }
 
 void DWARFDebugLine::SectionParser::skip(
-    function_ref<void(Error)> RecoverableErrorCallback,
-    function_ref<void(Error)> UnrecoverableErrorCallback) {
+    function_ref<void(Error)> RecoverableErrorHandler,
+    function_ref<void(Error)> UnrecoverableErrorHandler) {
   assert(DebugLineData.isValidOffset(Offset) &&
          "parsing should have terminated");
   DWARFUnit *U = prepareToParse(Offset);
   uint64_t OldOffset = Offset;
   LineTable LT;
   if (Error Err = LT.Prologue.parse(DebugLineData, &Offset,
-                                    RecoverableErrorCallback, Context, U))
-    UnrecoverableErrorCallback(std::move(Err));
+                                    RecoverableErrorHandler, Context, U))
+    UnrecoverableErrorHandler(std::move(Err));
   moveToNextTable(OldOffset, LT.Prologue);
 }
 
 DWARFUnit *DWARFDebugLine::SectionParser::prepareToParse(uint64_t Offset) {
   DWARFUnit *U = nullptr;
   auto It = LineToUnit.find(Offset);
   if (It != LineToUnit.end())
     U = It->second;