[MBP] Use Function::optForSize() instead of checking OptimizeForSize directly.

Fix a FIXME.  Disable loop alignment if compiled with -Oz now.

llvm-svn: 268121
diff --git a/llvm/lib/CodeGen/MachineBlockPlacement.cpp b/llvm/lib/CodeGen/MachineBlockPlacement.cpp
index 970be7f..baa9df6 100644
--- a/llvm/lib/CodeGen/MachineBlockPlacement.cpp
+++ b/llvm/lib/CodeGen/MachineBlockPlacement.cpp
@@ -1366,8 +1366,7 @@
   // exclusively on the loop info here so that we can align backedges in
   // unnatural CFGs and backedges that were introduced purely because of the
   // loop rotations done during this layout pass.
-  // FIXME: Use Function::optForSize().
-  if (F.getFunction()->hasFnAttribute(Attribute::OptimizeForSize))
+  if (F.getFunction()->optForSize())
     return;
   BlockChain &FunctionChain = *BlockToChain[&F.front()];
   if (FunctionChain.begin() == FunctionChain.end())