Only use the query for LocalCopy instances

Author: saethlin

Cargo.lock

@@ -3522,6 +3522,7 @@ dependencies = [
  "rustc_macros",
  "rustc_metadata",
  "rustc_middle",
+ "rustc_mir_transform",
  "rustc_query_system",
  "rustc_serialize",
  "rustc_session",

compiler/rustc_codegen_ssa/Cargo.toml

@@ -32,6 +32,7 @@ rustc_index = { path = "../rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_metadata = { path = "../rustc_metadata" }
 rustc_middle = { path = "../rustc_middle" }
+rustc_mir_transform = { path = "../rustc_mir_transform" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -3,6 +3,7 @@ use std::iter;
 use rustc_index::IndexVec;
 use rustc_index::bit_set::DenseBitSet;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
+use rustc_middle::mir::mono::{InstantiationMode, MonoItem};
 use rustc_middle::mir::{Body, Local, UnwindTerminateReason, traversal};
 use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, TyAndLayout};
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
@@ -168,7 +169,12 @@ pub fn lower_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     let tcx = cx.tcx();
     let llfn = cx.get_fn(instance);
 
-    let mut mir = tcx.codegen_mir(instance);
+    let mut mir = match MonoItem::Fn(instance).instantiation_mode(tcx) {
+        InstantiationMode::LocalCopy => tcx.build_codegen_mir(instance),
+        InstantiationMode::GloballyShared { .. } => {
+            rustc_mir_transform::build_codegen_mir(tcx, instance)
+        }
+    };
 
     let fn_abi = cx.fn_abi_of_instance(instance, ty::List::empty());
     debug!("fn_abi: {:?}", fn_abi);