Merge remote-tracking branch 'origin/master' into frewsxcv-san

9 files changed, 136 insertions, 70 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/lto.rs b/compiler/rustc_codegen_llvm/src/back/lto.rs
index 64fd1d09cc2..29415973ed0 100644
--- a/compiler/rustc_codegen_llvm/src/back/lto.rs
+++ b/compiler/rustc_codegen_llvm/src/back/lto.rs
@@ -6,7 +6,9 @@ use crate::llvm::{self, build_string, False, True};
 use crate::{LlvmCodegenBackend, ModuleLlvm};
 use rustc_codegen_ssa::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule, ThinShared};
 use rustc_codegen_ssa::back::symbol_export;
-use rustc_codegen_ssa::back::write::{CodegenContext, FatLTOInput, ModuleConfig};
+use rustc_codegen_ssa::back::write::{
+    CodegenContext, FatLTOInput, ModuleConfig, TargetMachineFactoryConfig,
+};
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::{looks_like_rust_object_file, ModuleCodegen, ModuleKind};
 use rustc_data_structures::fx::FxHashMap;
@@ -728,7 +730,14 @@ pub unsafe fn optimize_thin_module(
     cgcx: &CodegenContext<LlvmCodegenBackend>,
 ) -> Result<ModuleCodegen<ModuleLlvm>, FatalError> {
     let diag_handler = cgcx.create_diag_handler();
-    let tm = (cgcx.tm_factory.0)().map_err(|e| write::llvm_err(&diag_handler, &e))?;
+
+    let module_name = &thin_module.shared.module_names[thin_module.idx];
+    let split_dwarf_file = cgcx
+        .output_filenames
+        .split_dwarf_filename(cgcx.split_dwarf_kind, Some(module_name.to_str().unwrap()));
+    let tm_factory_config = TargetMachineFactoryConfig { split_dwarf_file };
+    let tm =
+        (cgcx.tm_factory)(tm_factory_config).map_err(|e| write::llvm_err(&diag_handler, &e))?;
 
     // Right now the implementation we've got only works over serialized
     // modules, so we create a fresh new LLVM context and parse the module
@@ -736,12 +745,8 @@ pub unsafe fn optimize_thin_module(
     // crates but for locally codegened modules we may be able to reuse
     // that LLVM Context and Module.
     let llcx = llvm::LLVMRustContextCreate(cgcx.fewer_names);
-    let llmod_raw = parse_module(
-        llcx,
-        &thin_module.shared.module_names[thin_module.idx],
-        thin_module.data(),
-        &diag_handler,
-    )? as *const _;
+    let llmod_raw =
+        parse_module(llcx, &module_name, thin_module.data(), &diag_handler)? as *const _;
     let module = ModuleCodegen {
         module_llvm: ModuleLlvm { llmod_raw, llcx, tm },
         name: thin_module.name().to_string(),
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 7407dfc455d..230e11f274e 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -11,7 +11,10 @@ use crate::llvm_util;
 use crate::type_::Type;
 use crate::LlvmCodegenBackend;
 use crate::ModuleLlvm;
-use rustc_codegen_ssa::back::write::{BitcodeSection, CodegenContext, EmitObj, ModuleConfig};
+use rustc_codegen_ssa::back::write::{
+    BitcodeSection, CodegenContext, EmitObj, ModuleConfig, TargetMachineFactoryConfig,
+    TargetMachineFactoryFn,
+};
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::{CompiledModule, ModuleCodegen};
 use rustc_data_structures::small_c_str::SmallCStr;
@@ -20,7 +23,9 @@ use rustc_fs_util::{link_or_copy, path_to_c_string};
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::bug;
 use rustc_middle::ty::TyCtxt;
-use rustc_session::config::{self, Lto, OutputType, Passes, SanitizerSet, SwitchWithOptPath};
+use rustc_session::config::{
+    self, Lto, OutputType, Passes, SanitizerSet, SplitDwarfKind, SwitchWithOptPath,
+};
 use rustc_session::Session;
 use rustc_span::symbol::sym;
 use rustc_span::InnerSpan;
@@ -49,11 +54,31 @@ pub fn write_output_file(
     pm: &llvm::PassManager<'ll>,
     m: &'ll llvm::Module,
     output: &Path,
+    dwo_output: Option<&Path>,
     file_type: llvm::FileType,
 ) -> Result<(), FatalError> {
     unsafe {
         let output_c = path_to_c_string(output);
-        let result = llvm::LLVMRustWriteOutputFile(target, pm, m, output_c.as_ptr(), file_type);
+        let result = if let Some(dwo_output) = dwo_output {
+            let dwo_output_c = path_to_c_string(dwo_output);
+            llvm::LLVMRustWriteOutputFile(
+                target,
+                pm,
+                m,
+                output_c.as_ptr(),
+                dwo_output_c.as_ptr(),
+                file_type,
+            )
+        } else {
+            llvm::LLVMRustWriteOutputFile(
+                target,
+                pm,
+                m,
+                output_c.as_ptr(),
+                std::ptr::null(),
+                file_type,
+            )
+        };
         result.into_result().map_err(|()| {
             let msg = format!("could not write output to {}", output.display());
             llvm_err(handler, &msg)
@@ -62,12 +87,17 @@ pub fn write_output_file(
 }
 
 pub fn create_informational_target_machine(sess: &Session) -> &'static mut llvm::TargetMachine {
-    target_machine_factory(sess, config::OptLevel::No)()
+    let config = TargetMachineFactoryConfig { split_dwarf_file: None };
+    target_machine_factory(sess, config::OptLevel::No)(config)
         .unwrap_or_else(|err| llvm_err(sess.diagnostic(), &err).raise())
 }
 
-pub fn create_target_machine(tcx: TyCtxt<'_>) -> &'static mut llvm::TargetMachine {
-    target_machine_factory(&tcx.sess, tcx.backend_optimization_level(LOCAL_CRATE))()
+pub fn create_target_machine(tcx: TyCtxt<'_>, mod_name: &str) -> &'static mut llvm::TargetMachine {
+    let split_dwarf_file = tcx
+        .output_filenames(LOCAL_CRATE)
+        .split_dwarf_filename(tcx.sess.opts.debugging_opts.split_dwarf, Some(mod_name));
+    let config = TargetMachineFactoryConfig { split_dwarf_file };
+    target_machine_factory(&tcx.sess, tcx.backend_optimization_level(LOCAL_CRATE))(config)
         .unwrap_or_else(|err| llvm_err(tcx.sess.diagnostic(), &err).raise())
 }
 
@@ -122,7 +152,7 @@ fn to_llvm_code_model(code_model: Option<CodeModel>) -> llvm::CodeModel {
 pub fn target_machine_factory(
     sess: &Session,
     optlvl: config::OptLevel,
-) -> Arc<dyn Fn() -> Result<&'static mut llvm::TargetMachine, String> + Send + Sync> {
+) -> TargetMachineFactoryFn<LlvmCodegenBackend> {
     let reloc_model = to_llvm_relocation_model(sess.relocation_model());
 
     let (opt_level, _) = to_llvm_opt_settings(optlvl);
@@ -163,7 +193,10 @@ pub fn target_machine_factory(
     let use_init_array =
         !sess.opts.debugging_opts.use_ctors_section.unwrap_or(sess.target.use_ctors_section);
 
-    Arc::new(move || {
+    Arc::new(move |config: TargetMachineFactoryConfig| {
+        let split_dwarf_file = config.split_dwarf_file.unwrap_or_default();
+        let split_dwarf_file = CString::new(split_dwarf_file.to_str().unwrap()).unwrap();
+
         let tm = unsafe {
             llvm::LLVMRustCreateTargetMachine(
                 triple.as_ptr(),
@@ -182,6 +215,7 @@ pub fn target_machine_factory(
                 emit_stack_size_section,
                 relax_elf_relocations,
                 use_init_array,
+                split_dwarf_file.as_ptr(),
             )
         };
 
@@ -451,7 +485,7 @@ pub(crate) unsafe fn optimize(
     diag_handler: &Handler,
     module: &ModuleCodegen<ModuleLlvm>,
     config: &ModuleConfig,
-) -> Result<(), FatalError> {
+) {
     let _timer = cgcx.prof.generic_activity_with_arg("LLVM_module_optimize", &module.name[..]);
 
     let llmod = module.module_llvm.llmod();
@@ -477,7 +511,7 @@ pub(crate) unsafe fn optimize(
                 _ => llvm::OptStage::PreLinkNoLTO,
             };
             optimize_with_new_llvm_pass_manager(cgcx, module, config, opt_level, opt_stage);
-            return Ok(());
+            return;
         }
 
         if cgcx.prof.llvm_recording_enabled() {
@@ -600,7 +634,6 @@ pub(crate) unsafe fn optimize(
         llvm::LLVMDisposePassManager(fpm);
         llvm::LLVMDisposePassManager(mpm);
     }
-    Ok(())
 }
 
 unsafe fn add_sanitizer_passes(config: &ModuleConfig, passes: &mut Vec<&'static mut llvm::Pass>) {
@@ -785,7 +818,15 @@ pub(crate) unsafe fn codegen(
                 llmod
             };
             with_codegen(tm, llmod, config.no_builtins, |cpm| {
-                write_output_file(diag_handler, tm, cpm, llmod, &path, llvm::FileType::AssemblyFile)
+                write_output_file(
+                    diag_handler,
+                    tm,
+                    cpm,
+                    llmod,
+                    &path,
+                    None,
+                    llvm::FileType::AssemblyFile,
+                )
             })?;
         }
 
@@ -794,6 +835,15 @@ pub(crate) unsafe fn codegen(
                 let _timer = cgcx
                     .prof
                     .generic_activity_with_arg("LLVM_module_codegen_emit_obj", &module.name[..]);
+
+                let dwo_out = cgcx.output_filenames.temp_path_dwo(module_name);
+                let dwo_out = match cgcx.split_dwarf_kind {
+                    // Don't change how DWARF is emitted in single mode (or when disabled).
+                    SplitDwarfKind::None | SplitDwarfKind::Single => None,
+                    // Emit (a subset of the) DWARF into a separate file in split mode.
+                    SplitDwarfKind::Split => Some(dwo_out.as_path()),
+                };
+
                 with_codegen(tm, llmod, config.no_builtins, |cpm| {
                     write_output_file(
                         diag_handler,
@@ -801,6 +851,7 @@ pub(crate) unsafe fn codegen(
                         cpm,
                         llmod,
                         &obj_out,
+                        dwo_out,
                         llvm::FileType::ObjectFile,
                     )
                 })?;
@@ -828,6 +879,7 @@ pub(crate) unsafe fn codegen(
 
     Ok(module.into_compiled_module(
         config.emit_obj != EmitObj::None,
+        cgcx.split_dwarf_kind == SplitDwarfKind::Split,
         config.emit_bc,
         &cgcx.output_filenames,
     ))
diff --git a/compiler/rustc_codegen_llvm/src/base.rs b/compiler/rustc_codegen_llvm/src/base.rs
index 7d01f6a5499..d5be3132dee 100644
--- a/compiler/rustc_codegen_llvm/src/base.rs
+++ b/compiler/rustc_codegen_llvm/src/base.rs
@@ -1,17 +1,15 @@
-//! Codegen the completed AST to the LLVM IR.
-//!
-//! Some functions here, such as codegen_block and codegen_expr, return a value --
-//! the result of the codegen to LLVM -- while others, such as codegen_fn
-//! and mono_item, are called only for the side effect of adding a
-//! particular definition to the LLVM IR output we're producing.
+//! Codegen the MIR to the LLVM IR.
 //!
 //! Hopefully useful general knowledge about codegen:
 //!
-//! * There's no way to find out the `Ty` type of a Value. Doing so
+//! * There's no way to find out the [`Ty`] type of a [`Value`]. Doing so
 //!   would be "trying to get the eggs out of an omelette" (credit:
-//!   pcwalton). You can, instead, find out its `llvm::Type` by calling `val_ty`,
-//!   but one `llvm::Type` corresponds to many `Ty`s; for instance, `tup(int, int,
-//!   int)` and `rec(x=int, y=int, z=int)` will have the same `llvm::Type`.
+//!   pcwalton). You can, instead, find out its [`llvm::Type`] by calling [`val_ty`],
+//!   but one [`llvm::Type`] corresponds to many [`Ty`]s; for instance, `tup(int, int,
+//!   int)` and `rec(x=int, y=int, z=int)` will have the same [`llvm::Type`].
+//!
+//! [`Ty`]: rustc_middle::ty::Ty
+//! [`val_ty`]: common::val_ty
 
 use super::ModuleLlvm;
 
diff --git a/compiler/rustc_codegen_llvm/src/common.rs b/compiler/rustc_codegen_llvm/src/common.rs
index 34e1b7a6045..58af9d4cd04 100644
--- a/compiler/rustc_codegen_llvm/src/common.rs
+++ b/compiler/rustc_codegen_llvm/src/common.rs
@@ -314,6 +314,7 @@ impl ConstMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     }
 }
 
+/// Get the [LLVM type][Type] of a [`Value`].
 pub fn val_ty(v: &Value) -> &Type {
     unsafe { llvm::LLVMTypeOf(v) }
 }
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 96484034da7..36a21b38c03 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -993,9 +993,15 @@ pub fn compile_unit_metadata(
     let producer = format!("clang LLVM ({})", rustc_producer);
 
     let name_in_debuginfo = name_in_debuginfo.to_string_lossy();
-    let work_dir = tcx.sess.working_dir.0.to_string_lossy();
     let flags = "\0";
-    let split_name = "";
+
+    let out_dir = &tcx.output_filenames(LOCAL_CRATE).out_directory;
+    let split_name = tcx
+        .output_filenames(LOCAL_CRATE)
+        .split_dwarf_filename(tcx.sess.opts.debugging_opts.split_dwarf, Some(codegen_unit_name))
+        .unwrap_or_default();
+    let out_dir = out_dir.to_str().unwrap();
+    let split_name = split_name.to_str().unwrap();
 
     // FIXME(#60020):
     //
@@ -1020,8 +1026,8 @@ pub fn compile_unit_metadata(
             debug_context.builder,
             name_in_debuginfo.as_ptr().cast(),
             name_in_debuginfo.len(),
-            work_dir.as_ptr().cast(),
-            work_dir.len(),
+            out_dir.as_ptr().cast(),
+            out_dir.len(),
             llvm::ChecksumKind::None,
             ptr::null(),
             0,
@@ -1039,6 +1045,8 @@ pub fn compile_unit_metadata(
             split_name.as_ptr().cast(),
             split_name.len(),
             kind,
+            0,
+            tcx.sess.opts.debugging_opts.split_dwarf_inlining,
         );
 
         if tcx.sess.opts.debugging_opts.profile {
@@ -1409,10 +1417,11 @@ fn generator_layout_and_saved_local_names(
 
     let state_arg = mir::Local::new(1);
     for var in &body.var_debug_info {
-        if var.place.local != state_arg {
+        let place = if let mir::VarDebugInfoContents::Place(p) = var.value { p } else { continue };
+        if place.local != state_arg {
             continue;
         }
-        match var.place.projection[..] {
+        match place.projection[..] {
             [
                 // Deref of the `Pin<&mut Self>` state argument.
                 mir::ProjectionElem::Field(..),
@@ -2313,13 +2322,13 @@ fn set_members_of_composite_type(
             DIB(cx),
             composite_type_metadata,
             Some(type_array),
-            type_params,
+            Some(type_params),
         );
     }
 }
 
 /// Computes the type parameters for a type, if any, for the given metadata.
-fn compute_type_parameters(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>) -> Option<&'ll DIArray> {
+fn compute_type_parameters(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>) -> &'ll DIArray {
     if let ty::Adt(def, substs) = *ty.kind() {
         if substs.types().next().is_some() {
             let generics = cx.tcx.generics_of(def.did);
@@ -2349,10 +2358,10 @@ fn compute_type_parameters(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>) -> Option<&'
                 })
                 .collect();
 
-            return Some(create_DIArray(DIB(cx), &template_params[..]));
+            return create_DIArray(DIB(cx), &template_params[..]);
         }
     }
-    return Some(create_DIArray(DIB(cx), &[]));
+    return create_DIArray(DIB(cx), &[]);
 
     fn get_parameter_names(cx: &CodegenCx<'_, '_>, generics: &ty::Generics) -> Vec<Symbol> {
         let mut names = generics
diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs
index ec557b7a682..bf0d499e6c4 100644
--- a/compiler/rustc_codegen_llvm/src/intrinsic.rs
+++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs
@@ -854,8 +854,8 @@ fn generic_simd_intrinsic(
         ));
     }
 
-    if name_str.starts_with("simd_shuffle") {
-        let n: u64 = name_str["simd_shuffle".len()..].parse().unwrap_or_else(|_| {
+    if let Some(stripped) = name_str.strip_prefix("simd_shuffle") {
+        let n: u64 = stripped.parse().unwrap_or_else(|_| {
             span_bug!(span, "bad `simd_shuffle` instruction only caught in codegen?")
         });
 
diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs
index 5974b59d39e..92ac770aca5 100644
--- a/compiler/rustc_codegen_llvm/src/lib.rs
+++ b/compiler/rustc_codegen_llvm/src/lib.rs
@@ -19,7 +19,9 @@ use back::write::{create_informational_target_machine, create_target_machine};
 pub use llvm_util::target_features;
 use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_codegen_ssa::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule};
-use rustc_codegen_ssa::back::write::{CodegenContext, FatLTOInput, ModuleConfig};
+use rustc_codegen_ssa::back::write::{
+    CodegenContext, FatLTOInput, ModuleConfig, TargetMachineFactoryConfig, TargetMachineFactoryFn,
+};
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::ModuleCodegen;
 use rustc_codegen_ssa::{CodegenResults, CompiledModule};
@@ -34,7 +36,6 @@ use rustc_span::symbol::Symbol;
 
 use std::any::Any;
 use std::ffi::CStr;
-use std::sync::Arc;
 
 mod back {
     pub mod archive;
@@ -109,7 +110,7 @@ impl ExtraBackendMethods for LlvmCodegenBackend {
         &self,
         sess: &Session,
         optlvl: OptLevel,
-    ) -> Arc<dyn Fn() -> Result<&'static mut llvm::TargetMachine, String> + Send + Sync> {
+    ) -> TargetMachineFactoryFn<Self> {
         back::write::target_machine_factory(sess, optlvl)
     }
     fn target_cpu<'b>(&self, sess: &'b Session) -> &'b str {
@@ -159,7 +160,7 @@ impl WriteBackendMethods for LlvmCodegenBackend {
         module: &ModuleCodegen<Self::Module>,
         config: &ModuleConfig,
     ) -> Result<(), FatalError> {
-        back::write::optimize(cgcx, diag_handler, module, config)
+        Ok(back::write::optimize(cgcx, diag_handler, module, config))
     }
     unsafe fn optimize_thin(
         cgcx: &CodegenContext<Self>,
@@ -297,21 +298,19 @@ impl CodegenBackend for LlvmCodegenBackend {
         codegen_results: CodegenResults,
         outputs: &OutputFilenames,
     ) -> Result<(), ErrorReported> {
+        use crate::back::archive::LlvmArchiveBuilder;
+        use rustc_codegen_ssa::back::link::link_binary;
+
         // Run the linker on any artifacts that resulted from the LLVM run.
         // This should produce either a finished executable or library.
-        sess.time("link_crate", || {
-            use crate::back::archive::LlvmArchiveBuilder;
-            use rustc_codegen_ssa::back::link::link_binary;
-
-            let target_cpu = crate::llvm_util::target_cpu(sess);
-            link_binary::<LlvmArchiveBuilder<'_>>(
-                sess,
-                &codegen_results,
-                outputs,
-                &codegen_results.crate_name.as_str(),
-                target_cpu,
-            );
-        });
+        let target_cpu = crate::llvm_util::target_cpu(sess);
+        link_binary::<LlvmArchiveBuilder<'_>>(
+            sess,
+            &codegen_results,
+            outputs,
+            &codegen_results.crate_name.as_str(),
+            target_cpu,
+        );
 
         Ok(())
     }
@@ -331,7 +330,7 @@ impl ModuleLlvm {
         unsafe {
             let llcx = llvm::LLVMRustContextCreate(tcx.sess.fewer_names());
             let llmod_raw = context::create_module(tcx, llcx, mod_name) as *const _;
-            ModuleLlvm { llmod_raw, llcx, tm: create_target_machine(tcx) }
+            ModuleLlvm { llmod_raw, llcx, tm: create_target_machine(tcx, mod_name) }
         }
     }
 
@@ -352,7 +351,13 @@ impl ModuleLlvm {
         unsafe {
             let llcx = llvm::LLVMRustContextCreate(cgcx.fewer_names);
             let llmod_raw = back::lto::parse_module(llcx, name, buffer, handler)?;
-            let tm = match (cgcx.tm_factory.0)() {
+
+            let split_dwarf_file = cgcx
+                .output_filenames
+                .split_dwarf_filename(cgcx.split_dwarf_kind, Some(name.to_str().unwrap()));
+            let tm_factory_config = TargetMachineFactoryConfig { split_dwarf_file };
+
+            let tm = match (cgcx.tm_factory)(tm_factory_config) {
                 Ok(m) => m,
                 Err(e) => {
                     handler.struct_err(&e).emit();
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 41482d18946..707aaa2b53f 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -1830,6 +1830,8 @@ extern "C" {
         SplitName: *const c_char,
         SplitNameLen: size_t,
         kind: DebugEmissionKind,
+        DWOId: u64,
+        SplitDebugInlining: bool,
     ) -> &'a DIDescriptor;
 
     pub fn LLVMRustDIBuilderCreateFile(
@@ -2151,6 +2153,7 @@ extern "C" {
         EmitStackSizeSection: bool,
         RelaxELFRelocations: bool,
         UseInitArray: bool,
+        SplitDwarfFile: *const c_char,
     ) -> Option<&'static mut TargetMachine>;
     pub fn LLVMRustDisposeTargetMachine(T: &'static mut TargetMachine);
     pub fn LLVMRustAddBuilderLibraryInfo(
@@ -2179,6 +2182,7 @@ extern "C" {
         PM: &PassManager<'a>,
         M: &'a Module,
         Output: *const c_char,
+        DwoOutput: *const c_char,
         FileType: FileType,
     ) -> LLVMRustResult;
     pub fn LLVMRustOptimizeWithNewPassManager(
diff --git a/compiler/rustc_codegen_llvm/src/type_of.rs b/compiler/rustc_codegen_llvm/src/type_of.rs
index 8ea4768f77d..0876907e119 100644
--- a/compiler/rustc_codegen_llvm/src/type_of.rs
+++ b/compiler/rustc_codegen_llvm/src/type_of.rs
@@ -40,9 +40,7 @@ fn uncached_llvm_type<'a, 'tcx>(
         // 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::Adt(..) | ty::Closure(..) | ty::Foreign(..) | ty::Generator(..) | ty::Str
-            if !cx.sess().fewer_names() =>
-        {
+        ty::Adt(..) | ty::Closure(..) | ty::Foreign(..) | ty::Generator(..) | ty::Str => {
             let mut name = with_no_trimmed_paths(|| layout.ty.to_string());
             if let (&ty::Adt(def, _), &Variants::Single { index }) =
                 (layout.ty.kind(), &layout.variants)
@@ -58,12 +56,6 @@ fn uncached_llvm_type<'a, 'tcx>(
             }
             Some(name)
         }
-        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,
     };