3 files changed, 33 insertions, 19 deletions
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index 4ece08f6293..89c3e21632e 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -6,7 +6,6 @@ use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
 use crate::value::Value;
 use libc::{c_char, c_uint};
-use rustc_codegen_ssa::base::to_immediate;
 use rustc_codegen_ssa::common::{IntPredicate, RealPredicate, TypeKind};
 use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
 use rustc_codegen_ssa::mir::place::PlaceRef;
@@ -367,6 +366,20 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         (self.extract_value(res, 0), self.extract_value(res, 1))
     }
 
+    fn from_immediate(&mut self, val: Self::Value) -> Self::Value {
+        if self.cx().val_ty(val) == self.cx().type_i1() {
+            self.zext(val, self.cx().type_i8())
+        } else {
+            val
+        }
+    }
+    fn to_immediate_scalar(&mut self, val: Self::Value, scalar: &abi::Scalar) -> Self::Value {
+        if scalar.is_bool() {
+            return self.trunc(val, self.cx().type_i1());
+        }
+        val
+    }
+
     fn alloca(&mut self, ty: &'ll Type, align: Align) -> &'ll Value {
         let mut bx = Builder::with_cx(self.cx);
         bx.position_at_start(unsafe { llvm::LLVMGetFirstBasicBlock(self.llfn()) });
@@ -471,7 +484,7 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
                 }
                 load
             });
-            OperandValue::Immediate(to_immediate(self, llval, place.layout))
+            OperandValue::Immediate(self.to_immediate(llval, place.layout))
         } else if let abi::Abi::ScalarPair(ref a, ref b) = place.layout.abi {
             let b_offset = a.value.size(self).align_to(b.value.align(self).abi);
 
@@ -479,7 +492,7 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
                 let llptr = self.struct_gep(place.llval, i as u64);
                 let load = self.load(llptr, align);
                 scalar_load_metadata(self, load, scalar);
-                if scalar.is_bool() { self.trunc(load, self.type_i1()) } else { load }
+                self.to_immediate_scalar(load, scalar)
             };
 
             OperandValue::Pair(
diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs
index c1dfb83b135..951b9928cc9 100644
--- a/compiler/rustc_codegen_llvm/src/intrinsic.rs
+++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs
@@ -8,7 +8,7 @@ use crate::va_arg::emit_va_arg;
 use crate::value::Value;
 
 use rustc_ast as ast;
-use rustc_codegen_ssa::base::{compare_simd_types, to_immediate, wants_msvc_seh};
+use rustc_codegen_ssa::base::{compare_simd_types, wants_msvc_seh};
 use rustc_codegen_ssa::common::span_invalid_monomorphization_error;
 use rustc_codegen_ssa::common::{IntPredicate, TypeKind};
 use rustc_codegen_ssa::glue;
@@ -301,7 +301,7 @@ impl IntrinsicCallMethods<'tcx> for Builder<'a, 'll, 'tcx> {
                 unsafe {
                     llvm::LLVMSetAlignment(load, align);
                 }
-                to_immediate(self, load, self.layout_of(tp_ty))
+                self.to_immediate(load, self.layout_of(tp_ty))
             }
             sym::volatile_store => {
                 let dst = args[0].deref(self.cx());
diff --git a/compiler/rustc_codegen_llvm/src/type_of.rs b/compiler/rustc_codegen_llvm/src/type_of.rs
index 40870c66475..a02601eb43e 100644
--- a/compiler/rustc_codegen_llvm/src/type_of.rs
+++ b/compiler/rustc_codegen_llvm/src/type_of.rs
@@ -4,7 +4,6 @@ use crate::type_::Type;
 use rustc_codegen_ssa::traits::*;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{FnAbiExt, TyAndLayout};
-use rustc_middle::ty::print::obsolete::DefPathBasedNames;
 use rustc_middle::ty::{self, Ty, TypeFoldable};
 use rustc_target::abi::{Abi, AddressSpace, Align, FieldsShape};
 use rustc_target::abi::{Int, Pointer, F32, F64};
@@ -52,32 +51,34 @@ fn uncached_llvm_type<'a, 'tcx>(
     }
 
     let name = match layout.ty.kind {
-        ty::Closure(..) |
-        ty::Generator(..) |
-        ty::Adt(..) |
         // FIXME(eddyb) producing readable type names for trait objects can result
         // in problematically distinct types due to HRTB and subtyping (see #47638).
         // ty::Dynamic(..) |
-        ty::Foreign(..) |
-        ty::Str => {
-            let mut name = String::with_capacity(32);
-            let printer = DefPathBasedNames::new(cx.tcx, true, true);
-            printer.push_type_name(layout.ty, &mut name, false);
-            if let (&ty::Adt(def, _), &Variants::Single { index })
-                 = (&layout.ty.kind, &layout.variants)
+        ty::Adt(..) | ty::Closure(..) | ty::Foreign(..) | ty::Generator(..) | ty::Str
+            if !cx.sess().fewer_names() =>
+        {
+            let mut name = layout.ty.to_string();
+            if let (&ty::Adt(def, _), &Variants::Single { index }) =
+                (&layout.ty.kind, &layout.variants)
             {
                 if def.is_enum() && !def.variants.is_empty() {
                     write!(&mut name, "::{}", def.variants[index].ident).unwrap();
                 }
             }
-            if let (&ty::Generator(_, _, _), &Variants::Single { index })
-                 = (&layout.ty.kind, &layout.variants)
+            if let (&ty::Generator(_, _, _), &Variants::Single { index }) =
+                (&layout.ty.kind, &layout.variants)
             {
                 write!(&mut name, "::{}", ty::GeneratorSubsts::variant_name(index)).unwrap();
             }
             Some(name)
         }
-        _ => None
+        ty::Adt(..) => {
+            // If `Some` is returned then a named struct is created in LLVM. Name collisions are
+            // avoided by LLVM (with increasing suffixes). If rustc doesn't generate names then that
+            // can improve perf.
+            Some(String::new())
+        }
+        _ => None,
     };
 
     match layout.fields {