Merge from rustc

15 files changed, 102 insertions, 185 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index b802284eb32..58fa3c392ca 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -6,7 +6,7 @@ use std::fs::{File, OpenOptions, read};
 use std::io::{BufWriter, Write};
 use std::ops::{ControlFlow, Deref};
 use std::path::{Path, PathBuf};
-use std::process::{ExitStatus, Output, Stdio};
+use std::process::{Output, Stdio};
 use std::{env, fmt, fs, io, mem, str};
 
 use cc::windows_registry;
@@ -736,13 +736,10 @@ fn link_natively(
 
     // Invoke the system linker
     info!("{cmd:?}");
-    let retry_on_segfault = env::var("RUSTC_RETRY_LINKER_ON_SEGFAULT").is_ok();
     let unknown_arg_regex =
         Regex::new(r"(unknown|unrecognized) (command line )?(option|argument)").unwrap();
     let mut prog;
-    let mut i = 0;
     loop {
-        i += 1;
         prog = sess.time("run_linker", || exec_linker(sess, &cmd, out_filename, flavor, tmpdir));
         let Ok(ref output) = prog else {
             break;
@@ -858,54 +855,7 @@ fn link_natively(
             continue;
         }
 
-        // Here's a terribly awful hack that really shouldn't be present in any
-        // compiler. Here an environment variable is supported to automatically
-        // retry the linker invocation if the linker looks like it segfaulted.
-        //
-        // Gee that seems odd, normally segfaults are things we want to know
-        // about!  Unfortunately though in rust-lang/rust#38878 we're
-        // experiencing the linker segfaulting on Travis quite a bit which is
-        // causing quite a bit of pain to land PRs when they spuriously fail
-        // due to a segfault.
-        //
-        // The issue #38878 has some more debugging information on it as well,
-        // but this unfortunately looks like it's just a race condition in
-        // macOS's linker with some thread pool working in the background. It
-        // seems that no one currently knows a fix for this so in the meantime
-        // we're left with this...
-        if !retry_on_segfault || i > 3 {
-            break;
-        }
-        let msg_segv = "clang: error: unable to execute command: Segmentation fault: 11";
-        let msg_bus = "clang: error: unable to execute command: Bus error: 10";
-        if out.contains(msg_segv) || out.contains(msg_bus) {
-            warn!(
-                ?cmd, %out,
-                "looks like the linker segfaulted when we tried to call it, \
-                 automatically retrying again",
-            );
-            continue;
-        }
-
-        if is_illegal_instruction(&output.status) {
-            warn!(
-                ?cmd, %out, status = %output.status,
-                "looks like the linker hit an illegal instruction when we \
-                 tried to call it, automatically retrying again.",
-            );
-            continue;
-        }
-
-        #[cfg(unix)]
-        fn is_illegal_instruction(status: &ExitStatus) -> bool {
-            use std::os::unix::prelude::*;
-            status.signal() == Some(libc::SIGILL)
-        }
-
-        #[cfg(not(unix))]
-        fn is_illegal_instruction(_status: &ExitStatus) -> bool {
-            false
-        }
+        break;
     }
 
     match prog {
diff --git a/compiler/rustc_codegen_ssa/src/back/lto.rs b/compiler/rustc_codegen_ssa/src/back/lto.rs
index 9fd984b6419..ce6fe8a191b 100644
--- a/compiler/rustc_codegen_ssa/src/back/lto.rs
+++ b/compiler/rustc_codegen_ssa/src/back/lto.rs
@@ -56,12 +56,7 @@ impl<B: WriteBackendMethods> LtoModuleCodegen<B> {
     }
 
     /// Optimize this module within the given codegen context.
-    ///
-    /// This function is unsafe as it'll return a `ModuleCodegen` still
-    /// points to LLVM data structures owned by this `LtoModuleCodegen`.
-    /// It's intended that the module returned is immediately code generated and
-    /// dropped, and then this LTO module is dropped.
-    pub unsafe fn optimize(
+    pub fn optimize(
         self,
         cgcx: &CodegenContext<B>,
     ) -> Result<ModuleCodegen<B::Module>, FatalError> {
@@ -70,7 +65,7 @@ impl<B: WriteBackendMethods> LtoModuleCodegen<B> {
                 B::optimize_fat(cgcx, &mut module)?;
                 Ok(module)
             }
-            LtoModuleCodegen::Thin(thin) => unsafe { B::optimize_thin(cgcx, thin) },
+            LtoModuleCodegen::Thin(thin) => B::optimize_thin(cgcx, thin),
         }
     }
 
@@ -85,7 +80,7 @@ impl<B: WriteBackendMethods> LtoModuleCodegen<B> {
     }
 
     /// Run autodiff on Fat LTO module
-    pub unsafe fn autodiff(
+    pub fn autodiff(
         self,
         cgcx: &CodegenContext<B>,
         diff_fncs: Vec<AutoDiffItem>,
diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 0fd4ed8475b..a41ca8ce28b 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -383,7 +383,7 @@ pub struct CodegenContext<B: WriteBackendMethods> {
     pub coordinator_send: Sender<Box<dyn Any + Send>>,
     /// `true` if the codegen should be run in parallel.
     ///
-    /// Depends on [`CodegenBackend::supports_parallel()`] and `-Zno_parallel_backend`.
+    /// Depends on [`ExtraBackendMethods::supports_parallel()`] and `-Zno_parallel_backend`.
     pub parallel: bool,
 }
 
@@ -416,8 +416,7 @@ fn generate_lto_work<B: ExtraBackendMethods>(
             B::run_fat_lto(cgcx, needs_fat_lto, import_only_modules).unwrap_or_else(|e| e.raise());
         if cgcx.lto == Lto::Fat && !autodiff.is_empty() {
             let config = cgcx.config(ModuleKind::Regular);
-            module =
-                unsafe { module.autodiff(cgcx, autodiff, config).unwrap_or_else(|e| e.raise()) };
+            module = module.autodiff(cgcx, autodiff, config).unwrap_or_else(|e| e.raise());
         }
         // We are adding a single work item, so the cost doesn't matter.
         vec![(WorkItem::LTO(module), 0)]
@@ -887,9 +886,7 @@ fn execute_optimize_work_item<B: ExtraBackendMethods>(
     let dcx = cgcx.create_dcx();
     let dcx = dcx.handle();
 
-    unsafe {
-        B::optimize(cgcx, dcx, &mut module, module_config)?;
-    }
+    B::optimize(cgcx, dcx, &mut module, module_config)?;
 
     // After we've done the initial round of optimizations we need to
     // decide whether to synchronously codegen this module or ship it
@@ -1020,7 +1017,7 @@ fn execute_lto_work_item<B: ExtraBackendMethods>(
     module: lto::LtoModuleCodegen<B>,
     module_config: &ModuleConfig,
 ) -> Result<WorkItemResult<B>, FatalError> {
-    let module = unsafe { module.optimize(cgcx)? };
+    let module = module.optimize(cgcx)?;
     finish_intra_module_work(cgcx, module, module_config)
 }
 
@@ -1036,7 +1033,7 @@ fn finish_intra_module_work<B: ExtraBackendMethods>(
         || module.kind == ModuleKind::Metadata
         || module.kind == ModuleKind::Allocator
     {
-        let module = unsafe { B::codegen(cgcx, dcx, module, module_config)? };
+        let module = B::codegen(cgcx, dcx, module, module_config)?;
         Ok(WorkItemResult::Finished(module))
     } else {
         Ok(WorkItemResult::NeedsLink(module))
@@ -1725,9 +1722,8 @@ fn start_executing_work<B: ExtraBackendMethods>(
             let dcx = cgcx.create_dcx();
             let dcx = dcx.handle();
             let module = B::run_link(&cgcx, dcx, needs_link).map_err(|_| ())?;
-            let module = unsafe {
-                B::codegen(&cgcx, dcx, module, cgcx.config(ModuleKind::Regular)).map_err(|_| ())?
-            };
+            let module =
+                B::codegen(&cgcx, dcx, module, cgcx.config(ModuleKind::Regular)).map_err(|_| ())?;
             compiled_modules.push(module);
         }
 
diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
index 1890119dca7..f7863fe4ae2 100644
--- a/compiler/rustc_codegen_ssa/src/base.rs
+++ b/compiler/rustc_codegen_ssa/src/base.rs
@@ -492,6 +492,7 @@ where
 /// users main function.
 pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     cx: &'a Bx::CodegenCx,
+    cgu: &CodegenUnit<'tcx>,
 ) -> Option<Bx::Function> {
     let (main_def_id, entry_type) = cx.tcx().entry_fn(())?;
     let main_is_local = main_def_id.is_local();
@@ -500,10 +501,10 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     if main_is_local {
         // We want to create the wrapper in the same codegen unit as Rust's main
         // function.
-        if !cx.codegen_unit().contains_item(&MonoItem::Fn(instance)) {
+        if !cgu.contains_item(&MonoItem::Fn(instance)) {
             return None;
         }
-    } else if !cx.codegen_unit().is_primary() {
+    } else if !cgu.is_primary() {
         // We want to create the wrapper only when the codegen unit is the primary one
         return None;
     }
diff --git a/compiler/rustc_codegen_ssa/src/common.rs b/compiler/rustc_codegen_ssa/src/common.rs
index 6d0c9d8d066..ef0d565333e 100644
--- a/compiler/rustc_codegen_ssa/src/common.rs
+++ b/compiler/rustc_codegen_ssa/src/common.rs
@@ -60,15 +60,6 @@ pub enum AtomicRmwBinOp {
 }
 
 #[derive(Copy, Clone, Debug)]
-pub enum AtomicOrdering {
-    Relaxed,
-    Acquire,
-    Release,
-    AcquireRelease,
-    SequentiallyConsistent,
-}
-
-#[derive(Copy, Clone, Debug)]
 pub enum SynchronizationScope {
     SingleThread,
     CrossThread,
diff --git a/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs b/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
index a6d159c51e1..a79d67bb6cd 100644
--- a/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
@@ -99,6 +99,17 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
         let llret_ty = bx.backend_type(bx.layout_of(ret_ty));
 
+        let ret_llval = |bx: &mut Bx, llval| {
+            if result.layout.ty.is_bool() {
+                OperandRef::from_immediate_or_packed_pair(bx, llval, result.layout)
+                    .val
+                    .store(bx, result);
+            } else if !result.layout.ty.is_unit() {
+                bx.store_to_place(llval, result.val);
+            }
+            Ok(())
+        };
+
         let llval = match name {
             sym::abort => {
                 bx.abort();
@@ -334,9 +345,48 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             // This requires that atomic intrinsics follow a specific naming pattern:
             // "atomic_<operation>[_<ordering>]"
             name if let Some(atomic) = name_str.strip_prefix("atomic_") => {
-                use crate::common::AtomicOrdering::*;
+                use rustc_middle::ty::AtomicOrdering::*;
+
                 use crate::common::{AtomicRmwBinOp, SynchronizationScope};
 
+                let invalid_monomorphization = |ty| {
+                    bx.tcx().dcx().emit_err(InvalidMonomorphization::BasicIntegerType {
+                        span,
+                        name,
+                        ty,
+                    });
+                };
+
+                let parse_const_generic_ordering = |ord: ty::Value<'tcx>| {
+                    let discr = ord.valtree.unwrap_branch()[0].unwrap_leaf();
+                    discr.to_atomic_ordering()
+                };
+
+                // Some intrinsics have the ordering already converted to a const generic parameter, we handle those first.
+                match name {
+                    sym::atomic_load => {
+                        let ty = fn_args.type_at(0);
+                        let ordering = fn_args.const_at(1).to_value();
+                        if !(int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_raw_ptr()) {
+                            invalid_monomorphization(ty);
+                            return Ok(());
+                        }
+                        let layout = bx.layout_of(ty);
+                        let source = args[0].immediate();
+                        let llval = bx.atomic_load(
+                            bx.backend_type(layout),
+                            source,
+                            parse_const_generic_ordering(ordering),
+                            layout.size,
+                        );
+
+                        return ret_llval(bx, llval);
+                    }
+
+                    // The rest falls back to below.
+                    _ => {}
+                }
+
                 let Some((instruction, ordering)) = atomic.split_once('_') else {
                     bx.sess().dcx().emit_fatal(errors::MissingMemoryOrdering);
                 };
@@ -345,19 +395,11 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     "relaxed" => Relaxed,
                     "acquire" => Acquire,
                     "release" => Release,
-                    "acqrel" => AcquireRelease,
-                    "seqcst" => SequentiallyConsistent,
+                    "acqrel" => AcqRel,
+                    "seqcst" => SeqCst,
                     _ => bx.sess().dcx().emit_fatal(errors::UnknownAtomicOrdering),
                 };
 
-                let invalid_monomorphization = |ty| {
-                    bx.tcx().dcx().emit_err(InvalidMonomorphization::BasicIntegerType {
-                        span,
-                        name,
-                        ty,
-                    });
-                };
-
                 match instruction {
                     "cxchg" | "cxchgweak" => {
                         let Some((success, failure)) = ordering.split_once('_') else {
@@ -390,24 +432,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         return Ok(());
                     }
 
-                    "load" => {
-                        let ty = fn_args.type_at(0);
-                        if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_raw_ptr() {
-                            let layout = bx.layout_of(ty);
-                            let size = layout.size;
-                            let source = args[0].immediate();
-                            bx.atomic_load(
-                                bx.backend_type(layout),
-                                source,
-                                parse_ordering(bx, ordering),
-                                size,
-                            )
-                        } else {
-                            invalid_monomorphization(ty);
-                            return Ok(());
-                        }
-                    }
-
                     "store" => {
                         let ty = fn_args.type_at(0);
                         if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_raw_ptr() {
@@ -538,14 +562,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             }
         };
 
-        if result.layout.ty.is_bool() {
-            OperandRef::from_immediate_or_packed_pair(bx, llval, result.layout)
-                .val
-                .store(bx, result);
-        } else if !result.layout.ty.is_unit() {
-            bx.store_to_place(llval, result.val);
-        }
-        Ok(())
+        ret_llval(bx, llval)
     }
 }
 
diff --git a/compiler/rustc_codegen_ssa/src/mono_item.rs b/compiler/rustc_codegen_ssa/src/mono_item.rs
index c2067e52afe..7b4268abe4b 100644
--- a/compiler/rustc_codegen_ssa/src/mono_item.rs
+++ b/compiler/rustc_codegen_ssa/src/mono_item.rs
@@ -11,11 +11,13 @@ pub trait MonoItemExt<'a, 'tcx> {
     fn define<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
         cx: &'a mut Bx::CodegenCx,
+        cgu_name: &str,
         item_data: MonoItemData,
     );
     fn predefine<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
-        cx: &'a Bx::CodegenCx,
+        cx: &'a mut Bx::CodegenCx,
+        cgu_name: &str,
         linkage: Linkage,
         visibility: Visibility,
     );
@@ -26,14 +28,10 @@ impl<'a, 'tcx: 'a> MonoItemExt<'a, 'tcx> for MonoItem<'tcx> {
     fn define<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
         cx: &'a mut Bx::CodegenCx,
+        cgu_name: &str,
         item_data: MonoItemData,
     ) {
-        debug!(
-            "BEGIN IMPLEMENTING '{} ({})' in cgu {}",
-            self,
-            self.to_raw_string(),
-            cx.codegen_unit().name()
-        );
+        debug!("BEGIN IMPLEMENTING '{} ({})' in cgu {}", self, self.to_raw_string(), cgu_name);
 
         match *self {
             MonoItem::Static(def_id) => {
@@ -56,26 +54,17 @@ impl<'a, 'tcx: 'a> MonoItemExt<'a, 'tcx> for MonoItem<'tcx> {
             }
         }
 
-        debug!(
-            "END IMPLEMENTING '{} ({})' in cgu {}",
-            self,
-            self.to_raw_string(),
-            cx.codegen_unit().name()
-        );
+        debug!("END IMPLEMENTING '{} ({})' in cgu {}", self, self.to_raw_string(), cgu_name);
     }
 
     fn predefine<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
-        cx: &'a Bx::CodegenCx,
+        cx: &'a mut Bx::CodegenCx,
+        cgu_name: &str,
         linkage: Linkage,
         visibility: Visibility,
     ) {
-        debug!(
-            "BEGIN PREDEFINING '{} ({})' in cgu {}",
-            self,
-            self.to_raw_string(),
-            cx.codegen_unit().name()
-        );
+        debug!("BEGIN PREDEFINING '{} ({})' in cgu {}", self, self.to_raw_string(), cgu_name);
 
         let symbol_name = self.symbol_name(cx.tcx()).name;
 
@@ -97,12 +86,7 @@ impl<'a, 'tcx: 'a> MonoItemExt<'a, 'tcx> for MonoItem<'tcx> {
             MonoItem::GlobalAsm(..) => {}
         }
 
-        debug!(
-            "END PREDEFINING '{} ({})' in cgu {}",
-            self,
-            self.to_raw_string(),
-            cx.codegen_unit().name()
-        );
+        debug!("END PREDEFINING '{} ({})' in cgu {}", self, self.to_raw_string(), cgu_name);
     }
 
     fn to_raw_string(&self) -> String {
diff --git a/compiler/rustc_codegen_ssa/src/traits/backend.rs b/compiler/rustc_codegen_ssa/src/traits/backend.rs
index e2f1458d062..95bf3b16685 100644
--- a/compiler/rustc_codegen_ssa/src/traits/backend.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/backend.rs
@@ -21,12 +21,12 @@ use crate::back::write::TargetMachineFactoryFn;
 use crate::{CodegenResults, ModuleCodegen, TargetConfig};
 
 pub trait BackendTypes {
-    type Value: CodegenObject;
+    type Value: CodegenObject + PartialEq;
     type Metadata: CodegenObject;
     type Function: CodegenObject;
 
     type BasicBlock: Copy;
-    type Type: CodegenObject;
+    type Type: CodegenObject + PartialEq;
     type Funclet;
 
     // FIXME(eddyb) find a common convention for all of the debuginfo-related
@@ -97,13 +97,6 @@ pub trait CodegenBackend {
     fn link(&self, sess: &Session, codegen_results: CodegenResults, outputs: &OutputFilenames) {
         link_binary(sess, &ArArchiveBuilderBuilder, codegen_results, outputs);
     }
-
-    /// Returns `true` if this backend can be safely called from multiple threads.
-    ///
-    /// Defaults to `true`.
-    fn supports_parallel(&self) -> bool {
-        true
-    }
 }
 
 pub trait ExtraBackendMethods:
@@ -144,4 +137,11 @@ pub trait ExtraBackendMethods:
     {
         std::thread::Builder::new().name(name).spawn(f)
     }
+
+    /// Returns `true` if this backend can be safely called from multiple threads.
+    ///
+    /// Defaults to `true`.
+    fn supports_parallel(&self) -> bool {
+        true
+    }
 }
diff --git a/compiler/rustc_codegen_ssa/src/traits/builder.rs b/compiler/rustc_codegen_ssa/src/traits/builder.rs
index f66309cf340..7f78bc75695 100644
--- a/compiler/rustc_codegen_ssa/src/traits/builder.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/builder.rs
@@ -4,7 +4,7 @@ use std::ops::Deref;
 use rustc_abi::{Align, Scalar, Size, WrappingRange};
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
-use rustc_middle::ty::{Instance, Ty};
+use rustc_middle::ty::{AtomicOrdering, Instance, Ty};
 use rustc_session::config::OptLevel;
 use rustc_span::Span;
 use rustc_target::callconv::FnAbi;
@@ -19,9 +19,7 @@ use super::misc::MiscCodegenMethods;
 use super::type_::{ArgAbiBuilderMethods, BaseTypeCodegenMethods, LayoutTypeCodegenMethods};
 use super::{CodegenMethods, StaticBuilderMethods};
 use crate::MemFlags;
-use crate::common::{
-    AtomicOrdering, AtomicRmwBinOp, IntPredicate, RealPredicate, SynchronizationScope, TypeKind,
-};
+use crate::common::{AtomicRmwBinOp, IntPredicate, RealPredicate, SynchronizationScope, TypeKind};
 use crate::mir::operand::{OperandRef, OperandValue};
 use crate::mir::place::{PlaceRef, PlaceValue};
 
@@ -514,11 +512,11 @@ pub trait BuilderMethods<'a, 'tcx>:
     fn extract_value(&mut self, agg_val: Self::Value, idx: u64) -> Self::Value;
     fn insert_value(&mut self, agg_val: Self::Value, elt: Self::Value, idx: u64) -> Self::Value;
 
-    fn set_personality_fn(&mut self, personality: Self::Value);
+    fn set_personality_fn(&mut self, personality: Self::Function);
 
     // These are used by everyone except msvc
-    fn cleanup_landing_pad(&mut self, pers_fn: Self::Value) -> (Self::Value, Self::Value);
-    fn filter_landing_pad(&mut self, pers_fn: Self::Value) -> (Self::Value, Self::Value);
+    fn cleanup_landing_pad(&mut self, pers_fn: Self::Function) -> (Self::Value, Self::Value);
+    fn filter_landing_pad(&mut self, pers_fn: Self::Function) -> (Self::Value, Self::Value);
     fn resume(&mut self, exn0: Self::Value, exn1: Self::Value);
 
     // These are used only by msvc
diff --git a/compiler/rustc_codegen_ssa/src/traits/declare.rs b/compiler/rustc_codegen_ssa/src/traits/declare.rs
index c1edeac31b0..9f735546558 100644
--- a/compiler/rustc_codegen_ssa/src/traits/declare.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/declare.rs
@@ -4,14 +4,14 @@ use rustc_middle::ty::Instance;
 
 pub trait PreDefineCodegenMethods<'tcx> {
     fn predefine_static(
-        &self,
+        &mut self,
         def_id: DefId,
         linkage: Linkage,
         visibility: Visibility,
         symbol_name: &str,
     );
     fn predefine_fn(
-        &self,
+        &mut self,
         instance: Instance<'tcx>,
         linkage: Linkage,
         visibility: Visibility,
diff --git a/compiler/rustc_codegen_ssa/src/traits/misc.rs b/compiler/rustc_codegen_ssa/src/traits/misc.rs
index 4004947b464..710fab27901 100644
--- a/compiler/rustc_codegen_ssa/src/traits/misc.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/misc.rs
@@ -1,7 +1,6 @@
 use std::cell::RefCell;
 
 use rustc_data_structures::fx::FxHashMap;
-use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::ty::{self, Instance, Ty};
 use rustc_session::Session;
 
@@ -20,9 +19,8 @@ pub trait MiscCodegenMethods<'tcx>: BackendTypes {
     }
     fn get_fn(&self, instance: Instance<'tcx>) -> Self::Function;
     fn get_fn_addr(&self, instance: Instance<'tcx>) -> Self::Value;
-    fn eh_personality(&self) -> Self::Value;
+    fn eh_personality(&self) -> Self::Function;
     fn sess(&self) -> &Session;
-    fn codegen_unit(&self) -> &'tcx CodegenUnit<'tcx>;
     fn set_frame_pointer_type(&self, llfn: Self::Function);
     fn apply_target_cpu_attr(&self, llfn: Self::Function);
     /// Declares the extern "C" main function for the entry point. Returns None if the symbol
diff --git a/compiler/rustc_codegen_ssa/src/traits/mod.rs b/compiler/rustc_codegen_ssa/src/traits/mod.rs
index 239857a4298..6d1ac717c0b 100644
--- a/compiler/rustc_codegen_ssa/src/traits/mod.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/mod.rs
@@ -50,7 +50,7 @@ pub use self::type_::{
 };
 pub use self::write::{ModuleBufferMethods, ThinBufferMethods, WriteBackendMethods};
 
-pub trait CodegenObject = Copy + PartialEq + fmt::Debug;
+pub trait CodegenObject = Copy + fmt::Debug;
 
 pub trait CodegenMethods<'tcx> = LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
     + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
diff --git a/compiler/rustc_codegen_ssa/src/traits/statics.rs b/compiler/rustc_codegen_ssa/src/traits/statics.rs
index ece0ea1b2ea..0e1e445c72f 100644
--- a/compiler/rustc_codegen_ssa/src/traits/statics.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/statics.rs
@@ -5,19 +5,7 @@ use super::BackendTypes;
 
 pub trait StaticCodegenMethods: BackendTypes {
     fn static_addr_of(&self, cv: Self::Value, align: Align, kind: Option<&str>) -> Self::Value;
-    fn codegen_static(&self, def_id: DefId);
-
-    /// Mark the given global value as "used", to prevent the compiler and linker from potentially
-    /// removing a static variable that may otherwise appear unused.
-    fn add_used_global(&self, global: Self::Value);
-
-    /// Same as add_used_global(), but only prevent the compiler from potentially removing an
-    /// otherwise unused symbol. The linker is still permitted to drop it.
-    ///
-    /// This corresponds to the documented semantics of the `#[used]` attribute, although
-    /// on some targets (non-ELF), we may use `add_used_global` for `#[used]` statics
-    /// instead.
-    fn add_compiler_used_global(&self, global: Self::Value);
+    fn codegen_static(&mut self, def_id: DefId);
 }
 
 pub trait StaticBuilderMethods: BackendTypes {
diff --git a/compiler/rustc_codegen_ssa/src/traits/type_.rs b/compiler/rustc_codegen_ssa/src/traits/type_.rs
index 32d9f27d32d..c3fc21a9285 100644
--- a/compiler/rustc_codegen_ssa/src/traits/type_.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/type_.rs
@@ -158,7 +158,6 @@ pub trait ArgAbiBuilderMethods<'tcx>: BackendTypes {
         val: Self::Value,
         dst: PlaceRef<'tcx, Self::Value>,
     );
-    fn arg_memory_ty(&self, arg_abi: &ArgAbi<'tcx, Ty<'tcx>>) -> Self::Type;
 }
 
 pub trait TypeCodegenMethods<'tcx> = DerivedTypeCodegenMethods<'tcx>
diff --git a/compiler/rustc_codegen_ssa/src/traits/write.rs b/compiler/rustc_codegen_ssa/src/traits/write.rs
index c77efdd1728..07a0609fda1 100644
--- a/compiler/rustc_codegen_ssa/src/traits/write.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/write.rs
@@ -6,7 +6,7 @@ use crate::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule};
 use crate::back::write::{CodegenContext, FatLtoInput, ModuleConfig};
 use crate::{CompiledModule, ModuleCodegen};
 
-pub trait WriteBackendMethods: 'static + Sized + Clone {
+pub trait WriteBackendMethods: Clone + 'static {
     type Module: Send + Sync;
     type TargetMachine;
     type TargetMachineError;
@@ -37,7 +37,7 @@ pub trait WriteBackendMethods: 'static + Sized + Clone {
     ) -> Result<(Vec<LtoModuleCodegen<Self>>, Vec<WorkProduct>), FatalError>;
     fn print_pass_timings(&self);
     fn print_statistics(&self);
-    unsafe fn optimize(
+    fn optimize(
         cgcx: &CodegenContext<Self>,
         dcx: DiagCtxtHandle<'_>,
         module: &mut ModuleCodegen<Self::Module>,
@@ -47,11 +47,11 @@ pub trait WriteBackendMethods: 'static + Sized + Clone {
         cgcx: &CodegenContext<Self>,
         llmod: &mut ModuleCodegen<Self::Module>,
     ) -> Result<(), FatalError>;
-    unsafe fn optimize_thin(
+    fn optimize_thin(
         cgcx: &CodegenContext<Self>,
         thin: ThinModule<Self>,
     ) -> Result<ModuleCodegen<Self::Module>, FatalError>;
-    unsafe fn codegen(
+    fn codegen(
         cgcx: &CodegenContext<Self>,
         dcx: DiagCtxtHandle<'_>,
         module: ModuleCodegen<Self::Module>,