Expand ParameterAttributes to 32 bits (in preparation
for adding alignment info, not there yet).  Clean up
interfaces to reference ParameterAttributes consistently.

llvm-svn: 47342
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index fe013e8..3f7cfcc 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -119,7 +119,7 @@
     const ParamAttrsList *A = Attrs[i];
     for (unsigned op = 0, e = A->size(); op != e; ++op) {
       Record.push_back(A->getParamIndex(op));
-      Record.push_back(A->getParamAttrsAtIndex(op));
+      Record.push_back((uint16_t)A->getParamAttrsAtIndex(op));
     }
     
     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);