Auto merge of #131650 - saethlin:post-mono-mir-opts, r=<try>

Add post-mono MIR passes to make mono-reachable analysis more accurate

r? ghost

Author: bors

compiler/rustc_codegen_cranelift/src/base.rs

@@ -41,7 +41,7 @@ pub(crate) fn codegen_fn<'tcx>(
     let symbol_name = tcx.symbol_name(instance).name.to_string();
     let _timer = tcx.prof.generic_activity_with_arg("codegen fn", &*symbol_name);
 
-    let mir = tcx.instance_mir(instance.def);
+    let mir = tcx.build_codegen_mir(instance);
     let _mir_guard = crate::PrintOnPanic(|| {
         let mut buf = Vec::new();
         with_no_trimmed_paths!({

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -167,7 +167,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
     let llfn = cx.get_fn(instance);
 
-    let mir = cx.tcx().instance_mir(instance.def);
+    let mir = cx.tcx().build_codegen_mir(instance);
 
     let fn_abi = cx.fn_abi_of_instance(instance, ty::List::empty());
     debug!("fn_abi: {:?}", fn_abi);