[ELF] Rename NameTypeEntry and its field "Type"

[MaskRay]

Summary

NameTypeEntry::Type is a bit-packed value of CU index+attributes, which is named cu_index_and_attrs in a local variable in gdb/dwarf2read.c:dw2_symtab_iter_next

CuIndexAndAttrs is more meaningful.

[MaskRay]

Also rename NameTypeEntry

[dblaikie]

Seems reasonable - the spec https://sourceware.org/gdb//onlinedocs/gdb/Index-Section-Format.html also describes these as "CU index+attributes" values.

ELF/SyntheticSections.h

public:
 
   struct CuEntry {
     uint64_t CuOffset;
     uint64_t CuLength;
   };
 
   struct NameTypeEntry {
     llvm::CachedHashStringRef Name;
-    uint32_t Type;
+    uint32_t CuIndexAndAttrs;
   };
 
   struct GdbChunk {
     InputSection *Sec;
     std::vector<AddressEntry> AddressAreas;
     std::vector<CuEntry> CompilationUnits;
   };
 

ELF/SyntheticSections.cpp

createSymbols(ArrayRef<std::vector<GdbIndexSection::NameTypeEntry>> NameTypes,
   parallelForEachN(0, Concurrency, [&](size_t ThreadId) {
     uint32_t I = 0;
     for (ArrayRef<NameTypeEntry> Entries : NameTypes) {
       for (const NameTypeEntry &Ent : Entries) {
         size_t ShardId = Ent.Name.hash() >> Shift;
         if ((ShardId & (Concurrency - 1)) != ThreadId)
           continue;
 
-        uint32_t V = Ent.Type + CuIdxs[I];
+        uint32_t V = Ent.CuIndexAndAttrs + CuIdxs[I];
         size_t &Idx = Map[ShardId][Ent.Name];
         if (Idx) {
           Symbols[ShardId][Idx - 1].CuVector.push_back(V);
           continue;
         }
 
         Idx = Symbols[ShardId].size() + 1;
         Symbols[ShardId].push_back({Ent.Name, {V}, 0, 0});