Revert "IR: add optional type to 'byval' function parameters"

The IRLinker doesn't delve into the new byval attribute when mapping types, and
this breaks LTO.

llvm-svn: 362029

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -747,7 +747,7 @@ void ModuleBitcodeWriter::writeAttributeGroupTable() {
         Record.push_back(1);
         Record.push_back(getAttrKindEncoding(Attr.getKindAsEnum()));
         Record.push_back(Attr.getValueAsInt());
-      } else if (Attr.isStringAttribute()) {
+      } else {
         StringRef Kind = Attr.getKindAsString();
         StringRef Val = Attr.getValueAsString();
 
@@ -758,13 +758,6 @@ void ModuleBitcodeWriter::writeAttributeGroupTable() {
           Record.append(Val.begin(), Val.end());
           Record.push_back(0);
         }
-      } else {
-        assert(Attr.isTypeAttribute());
-        Type *Ty = Attr.getValueAsType();
-        Record.push_back(Ty ? 6 : 5);
-        Record.push_back(getAttrKindEncoding(Attr.getKindAsEnum()));
-        if (Ty)
-          Record.push_back(VE.getTypeID(Attr.getValueAsType()));
       }
     }
 
@@ -4133,15 +4126,15 @@ void ModuleBitcodeWriter::write() {
   // Emit blockinfo, which defines the standard abbreviations etc.
   writeBlockInfo();
 
-  // Emit information describing all of the types in the module.
-  writeTypeTable();
-
   // Emit information about attribute groups.
   writeAttributeGroupTable();
 
   // Emit information about parameter attributes.
   writeAttributeTable();
 
+  // Emit information describing all of the types in the module.
+  writeTypeTable();
+
   writeComdats();
 
   // Emit top-level description of module, including target triple, inline asm,