Change how symbol sizes are handled in lib/Object.

COFF and MachO only define symbol sizes for common symbols. Reflect that
in the class hierarchy by having a method for common symbols only in the base
and a general one in ELF.

This avoids the need of using a magic value for the size, which had a few
problems
* Most callers didn't check for it.
* The ones that did could not tell the magic value from a file actually having
  that value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240529 91177308-0d34-0410-b5e6-96231b3b80d8

lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp

@@ -118,8 +118,8 @@ static std::error_code getOffset(const SymbolRef &Sym, uint64_t &Result) {
   if (std::error_code EC = Sym.getAddress(Address))
     return EC;
 
-  if (Address == UnknownAddressOrSize) {
-    Result = UnknownAddressOrSize;
+  if (Address == UnknownAddress) {
+    Result = UnknownAddress;
     return std::error_code();
   }
 
@@ -129,7 +129,7 @@ static std::error_code getOffset(const SymbolRef &Sym, uint64_t &Result) {
     return EC;
 
   if (SecI == Obj->section_end()) {
-    Result = UnknownAddressOrSize;
+    Result = UnknownAddress;
     return std::error_code();
   }
 
@@ -387,7 +387,7 @@ void RuntimeDyldImpl::computeTotalAllocSize(const ObjectFile &Obj,
     uint32_t Flags = I->getFlags();
     if (Flags & SymbolRef::SF_Common) {
       // Add the common symbols to a list.  We'll allocate them all below.
-      uint64_t Size = I->getSize();
+      uint64_t Size = I->getCommonSize();
       CommonSize += Size;
     }
   }
@@ -494,7 +494,7 @@ void RuntimeDyldImpl::emitCommonSymbols(const ObjectFile &Obj,
     }
 
     uint32_t Align = Sym.getAlignment();
-    uint64_t Size = Sym.getSize();
+    uint64_t Size = Sym.getCommonSize();
 
     CommonSize += Align + Size;
     SymbolsToAllocate.push_back(Sym);
@@ -517,7 +517,7 @@ void RuntimeDyldImpl::emitCommonSymbols(const ObjectFile &Obj,
   for (auto &Sym : SymbolsToAllocate) {
     uint32_t Align = Sym.getAlignment();
     StringRef Name;
-    uint64_t Size = Sym.getSize();
+    uint64_t Size = Sym.getCommonSize();
     Check(Sym.getName(Name));
     if (Align) {
       // This symbol has an alignment requirement.

lib/ExecutionEngine/RuntimeDyld/RuntimeDyldCOFF.cpp

@@ -64,18 +64,18 @@ RuntimeDyldCOFF::loadObject(const object::ObjectFile &O) {
 uint64_t RuntimeDyldCOFF::getSymbolOffset(const SymbolRef &Sym) {
   uint64_t Address;
   if (Sym.getAddress(Address))
-    return UnknownAddressOrSize;
+    return UnknownAddress;
 
-  if (Address == UnknownAddressOrSize)
-    return UnknownAddressOrSize;
+  if (Address == UnknownAddress)
+    return UnknownAddress;
 
   const ObjectFile *Obj = Sym.getObject();
   section_iterator SecI(Obj->section_end());
   if (Sym.getSection(SecI))
-    return UnknownAddressOrSize;
+    return UnknownAddress;
 
   if (SecI == Obj->section_end())
-    return UnknownAddressOrSize;
+    return UnknownAddress;
 
   uint64_t SectionAddress = SecI->getAddress();
   return Address - SectionAddress;