Change sroa threshold back.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39980 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/opt/opt.cpp b/tools/opt/opt.cpp
index 64b554c..fc71074 100644
--- a/tools/opt/opt.cpp
+++ b/tools/opt/opt.cpp
@@ -268,7 +268,7 @@
   addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
   addPass(PM, createCFGSimplificationPass());    // Merge & remove BBs
   // FIXME: Temporary!
-  addPass(PM, createScalarReplAggregatesPass(512)); // Break up aggregate allocas
+  addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
   addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
   addPass(PM, createCondPropagationPass());      // Propagate conditionals