[WebAssembly] Fix inaccurate comments / assertion messages

[sbc100]

wasm/Symbols.h

339

This a copied from ELF/Symbols.h. Lokos like it should be "SymbolUnion too small".

[aheejin]

• "SymbolUnion too small"

wasm/InputFiles.cpp

void ObjFile::dumpInfo() const {
   log("info for: " + getName() +
       "\n              Symbols : " + Twine(Symbols.size()) +
       "\n     Function Imports : " + Twine(WasmObj->getNumImportedFunctions()) +
       "\n       Global Imports : " + Twine(WasmObj->getNumImportedGlobals()));
 }
 
 // Relocations contain either symbol or type indices.  This function takes a
 // relocation and returns relocated index (i.e. translates from the input
-// sybmol/type space to the output symbol/type space).
+// symbol/type space to the output symbol/type space).
 uint32_t ObjFile::calcNewIndex(const WasmRelocation &Reloc) const {
   if (Reloc.Type == R_WEBASSEMBLY_TYPE_INDEX_LEB) {
     assert(TypeIsUsed[Reloc.Index]);
     return TypeMap[Reloc.Index];
   }
   return Symbols[Reloc.Index]->getOutputSymbolIndex();
 }
 

wasm/SymbolTable.cpp

 static void reportTypeError(const Symbol *Existing, const InputFile *File,
                             llvm::wasm::WasmSymbolType Type) {
   error("symbol type mismatch: " + toString(*Existing) + "\n>>> defined as " +
         toString(Existing->getWasmType()) + " in " +
         toString(Existing->getFile()) + "\n>>> defined as " + toString(Type) +
         " in " + toString(File));
 }
 
+// Check the type of new symbol matches that of the symbol is replacing.
+// For functions this can also involve verifying that the signatures match.
 static void checkFunctionType(Symbol *Existing, const InputFile *File,
                               const WasmSignature *NewSig) {
   auto ExistingFunction = dyn_cast<FunctionSymbol>(Existing);
   if (!ExistingFunction) {
     reportTypeError(Existing, File, WASM_SYMBOL_TYPE_FUNCTION);
     return;
   }
 
   if (!NewSig)
     return;
 
   const WasmSignature *OldSig = ExistingFunction->FunctionType;
   if (!OldSig) {
     ExistingFunction->FunctionType = NewSig;
     return;
   }
 
   if (*NewSig != *OldSig)
     warn("function signature mismatch: " + Existing->getName() +
          "\n>>> defined as " + toString(*OldSig) + " in " +
          toString(Existing->getFile()) + "\n>>> defined as " +
          toString(*NewSig) + " in " + toString(File));
 }
 
-// Check the type of new symbol matches that of the symbol is replacing.
-// For functions this can also involve verifying that the signatures match.
 static void checkGlobalType(const Symbol *Existing, const InputFile *File,
                             const WasmGlobalType *NewType) {
   if (!isa<GlobalSymbol>(Existing)) {
     reportTypeError(Existing, File, WASM_SYMBOL_TYPE_GLOBAL);
     return;
   }
 
   const WasmGlobalType *OldType = cast<GlobalSymbol>(Existing)->getGlobalType();

wasm/Symbols.h

public:
   void setGlobalIndex(uint32_t Index);
   bool hasGlobalIndex() const;
 
 protected:
   GlobalSymbol(StringRef Name, Kind K, uint32_t Flags, InputFile *F,
                const WasmGlobalType *GlobalType)
       : Symbol(Name, K, Flags, F), GlobalType(GlobalType) {}
 
-  // Explicit function type, needed for undefined or synthetic functions only.
-  // For regular defined globals this information comes from the InputChunk.
   const WasmGlobalType *GlobalType;
   uint32_t GlobalIndex = INVALID_INDEX;
 };
 
 class DefinedGlobal : public GlobalSymbol {
 public:
   DefinedGlobal(StringRef Name, uint32_t Flags, InputFile *File,
                 InputGlobal *Global);
union SymbolUnion {
   alignas(UndefinedGlobal) char G[sizeof(UndefinedGlobal)];
   alignas(SectionSymbol) char I[sizeof(SectionSymbol)];
 };
 
 template <typename T, typename... ArgT>
 T *replaceSymbol(Symbol *S, ArgT &&... Arg) {
   static_assert(std::is_trivially_destructible<T>(),
                 "Symbol types must be trivially destructible");
-  static_assert(sizeof(T) <= sizeof(SymbolUnion), "Symbol too small");
+  static_assert(sizeof(T) <= sizeof(SymbolUnion), "Symbol too large");
   static_assert(alignof(T) <= alignof(SymbolUnion),
                 "SymbolUnion not aligned enough");
   assert(static_cast<Symbol *>(static_cast<T *>(nullptr)) == nullptr &&
          "Not a Symbol");
 
   Symbol SymCopy = *S;
 
   T *S2 = new (S) T(std::forward<ArgT>(Arg)...);