diff --git a/src/librustc_codegen_ssa/base.rs b/src/librustc_codegen_ssa/base.rs
index e460a4a2e8c..af340008cd9 100644
--- a/src/librustc_codegen_ssa/base.rs
+++ b/src/librustc_codegen_ssa/base.rs
@@ -368,13 +368,7 @@ pub fn codegen_instance<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
     // release builds.
     info!("codegen_instance({})", instance);
 
-    let sig = instance.fn_sig(cx.tcx());
-    let sig = cx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
-
-    let lldecl = cx.get_fn(instance);
-
-    let mir = cx.tcx().instance_mir(instance.def);
-    mir::codegen_mir::<Bx>(cx, lldecl, mir, instance, sig);
+    mir::codegen_mir::<Bx>(cx, instance);
 }
 
 /// Creates the `main` function which will initialize the rust runtime and call
diff --git a/src/librustc_codegen_ssa/mir/mod.rs b/src/librustc_codegen_ssa/mir/mod.rs
index 600bdced4ed..f2f0f36824c 100644
--- a/src/librustc_codegen_ssa/mir/mod.rs
+++ b/src/librustc_codegen_ssa/mir/mod.rs
@@ -121,13 +121,16 @@ impl<'a, 'tcx, V: CodegenObject> LocalRef<'tcx, V> {
 
 pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     cx: &'a Bx::CodegenCx,
-    llfn: Bx::Function,
-    mir: mir::ReadOnlyBodyCache<'tcx, 'tcx>,
     instance: Instance<'tcx>,
-    sig: ty::FnSig<'tcx>,
 ) {
     assert!(!instance.substs.needs_infer());
 
+    let llfn = cx.get_fn(instance);
+
+    let mir = cx.tcx().instance_mir(instance.def);
+
+    let sig = instance.fn_sig(cx.tcx());
+    let sig = cx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
     let fn_abi = FnAbi::new(cx, sig, &[]);
     debug!("fn_abi: {:?}", fn_abi);