[sledge] Only call Llvm_analysis.verify_module in debug mode

Summary:
This isn't free and is expected to hold of bitcode produced by
clang/llvm. There are tests that fail verification, so keep it in
debug mode.

Reviewed By: kren1

Differential Revision: D15535438

fbshipit-source-id: 9390a8363

sledge/src/llair/frontend.ml

@@ -1383,7 +1383,9 @@ let translate : string -> Llair.t =
       Llvm_linker.linker_dispose link_ctx ;
       llmodule
   in
-  Llvm_analysis.verify_module llmodule |> Option.iter ~f:invalid_llvm ;
+  assert (
+    Llvm_analysis.verify_module llmodule |> Option.for_all ~f:invalid_llvm
+  ) ;
   transform ~gdce:(not single_bc_input) llmodule ;
   scan_locs llmodule ;
   scan_names llmodule ;