ty: remove obsolete printer

This commit removes the obsolete printer and replaces all uses of it
with `FmtPrinter`. Of the replaced uses, all but one use was in `debug!`
logging, two cases were notable:

- `MonoItem::to_string` is used in `-Z print-mono-items` and therefore
  affects the output of all codegen-units tests.
- `DefPathBasedNames` was used in `librustc_codegen_llvm/type_of.rs`
  with `LLVMStructCreateNamed` and that'll now get different values, but
  this should result in no functional change.

Signed-off-by: David Wood <david@davidtw.co>

2 files changed, 10 insertions, 18 deletions

diff --git a/compiler/rustc_mir/src/monomorphize/collector.rs b/compiler/rustc_mir/src/monomorphize/collector.rs
index d379f4ef428..43cac8e5ee6 100644
--- a/compiler/rustc_mir/src/monomorphize/collector.rs
+++ b/compiler/rustc_mir/src/monomorphize/collector.rs
@@ -191,7 +191,6 @@ use rustc_middle::mir::mono::{InstantiationMode, MonoItem};
 use rustc_middle::mir::visit::Visitor as MirVisitor;
 use rustc_middle::mir::{self, Local, Location};
 use rustc_middle::ty::adjustment::{CustomCoerceUnsized, PointerCast};
-use rustc_middle::ty::print::obsolete::DefPathBasedNames;
 use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts};
 use rustc_middle::ty::{self, GenericParamDefKind, Instance, Ty, TyCtxt, TypeFoldable};
 use rustc_session::config::EntryFnType;
@@ -348,7 +347,7 @@ fn collect_items_rec<'tcx>(
         // We've been here already, no need to search again.
         return;
     }
-    debug!("BEGIN collect_items_rec({})", starting_point.node.to_string(tcx, true));
+    debug!("BEGIN collect_items_rec({})", starting_point.node);
 
     let mut neighbors = Vec::new();
     let recursion_depth_reset;
@@ -397,7 +396,7 @@ fn collect_items_rec<'tcx>(
         recursion_depths.insert(def_id, depth);
     }
 
-    debug!("END collect_items_rec({})", starting_point.node.to_string(tcx, true));
+    debug!("END collect_items_rec({})", starting_point.node);
 }
 
 fn record_accesses<'a, 'tcx: 'a>(
@@ -992,7 +991,7 @@ impl ItemLikeVisitor<'v> for RootCollector<'_, 'v> {
                         let def_id = self.tcx.hir().local_def_id(item.hir_id);
                         debug!(
                             "RootCollector: ADT drop-glue for {}",
-                            def_id_to_string(self.tcx, def_id)
+                            self.tcx.def_path_str(def_id.to_def_id())
                         );
 
                         let ty = Instance::new(def_id.to_def_id(), InternalSubsts::empty())
@@ -1004,14 +1003,14 @@ impl ItemLikeVisitor<'v> for RootCollector<'_, 'v> {
             hir::ItemKind::GlobalAsm(..) => {
                 debug!(
                     "RootCollector: ItemKind::GlobalAsm({})",
-                    def_id_to_string(self.tcx, self.tcx.hir().local_def_id(item.hir_id))
+                    self.tcx.def_path_str(self.tcx.hir().local_def_id(item.hir_id).to_def_id())
                 );
                 self.output.push(dummy_spanned(MonoItem::GlobalAsm(item.hir_id)));
             }
             hir::ItemKind::Static(..) => {
-                let def_id = self.tcx.hir().local_def_id(item.hir_id);
-                debug!("RootCollector: ItemKind::Static({})", def_id_to_string(self.tcx, def_id));
-                self.output.push(dummy_spanned(MonoItem::Static(def_id.to_def_id())));
+                let def_id = self.tcx.hir().local_def_id(item.hir_id).to_def_id();
+                debug!("RootCollector: ItemKind::Static({})", self.tcx.def_path_str(def_id));
+                self.output.push(dummy_spanned(MonoItem::Static(def_id)));
             }
             hir::ItemKind::Const(..) => {
                 // const items only generate mono items if they are
@@ -1134,7 +1133,7 @@ fn create_mono_items_for_default_impls<'tcx>(
 
             debug!(
                 "create_mono_items_for_default_impls(item={})",
-                def_id_to_string(tcx, impl_def_id)
+                tcx.def_path_str(impl_def_id.to_def_id())
             );
 
             if let Some(trait_ref) = tcx.impl_trait_ref(impl_def_id) {
@@ -1218,13 +1217,6 @@ fn collect_neighbours<'tcx>(
     MirNeighborCollector { tcx, body: &body, output, instance }.visit_body(&body);
 }
 
-fn def_id_to_string(tcx: TyCtxt<'_>, def_id: LocalDefId) -> String {
-    let mut output = String::new();
-    let printer = DefPathBasedNames::new(tcx, false, false);
-    printer.push_def_path(def_id.to_def_id(), &mut output);
-    output
-}
-
 fn collect_const_value<'tcx>(
     tcx: TyCtxt<'tcx>,
     value: ConstValue<'tcx>,
diff --git a/compiler/rustc_mir/src/monomorphize/partitioning/mod.rs b/compiler/rustc_mir/src/monomorphize/partitioning/mod.rs
index 9dfbd65e1b1..5747c016357 100644
--- a/compiler/rustc_mir/src/monomorphize/partitioning/mod.rs
+++ b/compiler/rustc_mir/src/monomorphize/partitioning/mod.rs
@@ -246,7 +246,7 @@ where
 
                 debug!(
                     " - {} [{:?}] [{}] estimated size {}",
-                    mono_item.to_string(tcx, true),
+                    mono_item,
                     linkage,
                     symbol_hash,
                     mono_item.size_estimate(tcx)
@@ -374,7 +374,7 @@ fn collect_and_partition_mono_items<'tcx>(
         let mut item_keys: Vec<_> = items
             .iter()
             .map(|i| {
-                let mut output = i.to_string(tcx, false);
+                let mut output = i.to_string();
                 output.push_str(" @@");
                 let mut empty = Vec::new();
                 let cgus = item_to_cgus.get_mut(i).unwrap_or(&mut empty);