[IR] Refactor attribute methods in Function class (NFC)

Rename the functions that query the optimization kind attributes.

Differential revision: https://reviews.llvm.org/D60287

llvm-svn: 357731
diff --git a/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp b/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
index 60d27d3..7526610 100644
--- a/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
@@ -529,7 +529,7 @@
     }
 
     if (!Checks.empty() || !LAI.getPSE().getUnionPredicate().isAlwaysTrue()) {
-      if (L->getHeader()->getParent()->optForSize()) {
+      if (L->getHeader()->getParent()->hasOptSize()) {
         LLVM_DEBUG(
             dbgs() << "Versioning is needed but not allowed when optimizing "
                       "for size.\n");