Remove a couple of uses of interior mutability around statics

Author: bjorn3

compiler/rustc_codegen_gcc/src/consts.rs

@@ -67,7 +67,7 @@ impl<'gcc, 'tcx> StaticCodegenMethods for CodegenCx<'gcc, 'tcx> {
     }
 
     #[cfg_attr(not(feature = "master"), allow(unused_mut))]
-    fn codegen_static(&self, def_id: DefId) {
+    fn codegen_static(&mut self, def_id: DefId) {
         let attrs = self.tcx.codegen_fn_attrs(def_id);
 
         let Ok((value, alloc)) = codegen_static_initializer(self, def_id) else {
@@ -162,11 +162,11 @@ impl<'gcc, 'tcx> StaticCodegenMethods for CodegenCx<'gcc, 'tcx> {
     }
 
     /// Add a global value to a list to be stored in the `llvm.used` variable, an array of i8*.
-    fn add_used_global(&self, _global: RValue<'gcc>) {
+    fn add_used_global(&mut self, _global: RValue<'gcc>) {
         // TODO(antoyo)
     }
 
-    fn add_compiler_used_global(&self, global: RValue<'gcc>) {
+    fn add_compiler_used_global(&mut self, global: RValue<'gcc>) {
         // NOTE: seems like GCC does not make the distinction between compiler.used and used.
         self.add_used_global(global);
     }

compiler/rustc_codegen_llvm/src/base.rs

@@ -115,14 +115,11 @@ pub(crate) fn compile_codegen_unit(
             }
 
             // Create the llvm.used and llvm.compiler.used variables.
-            if !cx.used_statics.borrow().is_empty() {
-                cx.create_used_variable_impl(c"llvm.used", &*cx.used_statics.borrow());
+            if !cx.used_statics.is_empty() {
+                cx.create_used_variable_impl(c"llvm.used", &cx.used_statics);
             }
-            if !cx.compiler_used_statics.borrow().is_empty() {
-                cx.create_used_variable_impl(
-                    c"llvm.compiler.used",
-                    &*cx.compiler_used_statics.borrow(),
-                );
+            if !cx.compiler_used_statics.is_empty() {
+                cx.create_used_variable_impl(c"llvm.compiler.used", &cx.compiler_used_statics);
             }
 
             // Run replace-all-uses-with for statics that need it. This must

compiler/rustc_codegen_llvm/src/consts.rs

@@ -411,7 +411,7 @@ impl<'ll> CodegenCx<'ll, '_> {
         g
     }
 
-    fn codegen_static_item(&self, def_id: DefId) {
+    fn codegen_static_item(&mut self, def_id: DefId) {
         unsafe {
             assert!(
                 llvm::LLVMGetInitializer(
@@ -571,18 +571,18 @@ impl<'ll> StaticCodegenMethods for CodegenCx<'ll, '_> {
         self.const_pointercast(gv, self.type_ptr())
     }
 
-    fn codegen_static(&self, def_id: DefId) {
+    fn codegen_static(&mut self, def_id: DefId) {
         self.codegen_static_item(def_id)
     }
 
     /// Add a global value to a list to be stored in the `llvm.used` variable, an array of ptr.
-    fn add_used_global(&self, global: &'ll Value) {
-        self.used_statics.borrow_mut().push(global);
+    fn add_used_global(&mut self, global: &'ll Value) {
+        self.used_statics.push(global);
     }
 
     /// Add a global value to a list to be stored in the `llvm.compiler.used` variable,
     /// an array of ptr.
-    fn add_compiler_used_global(&self, global: &'ll Value) {
-        self.compiler_used_statics.borrow_mut().push(global);
+    fn add_compiler_used_global(&mut self, global: &'ll Value) {
+        self.compiler_used_statics.push(global);
     }
 }

compiler/rustc_codegen_llvm/src/context.rs

@@ -2,7 +2,7 @@ use std::borrow::Borrow;
 use std::cell::{Cell, RefCell};
 use std::ffi::{CStr, c_char, c_uint};
 use std::marker::PhantomData;
-use std::ops::Deref;
+use std::ops::{Deref, DerefMut};
 use std::str;
 
 use rustc_abi::{HasDataLayout, Size, TargetDataLayout, VariantIdx};
@@ -77,6 +77,13 @@ impl<'ll, T: Borrow<SCx<'ll>>> Deref for GenericCx<'ll, T> {
     }
 }
 
+impl<'ll, T: Borrow<SCx<'ll>>> DerefMut for GenericCx<'ll, T> {
+    #[inline]
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+
 pub(crate) type SimpleCx<'ll> = GenericCx<'ll, SCx<'ll>>;
 
 /// There is one `CodegenCx` per codegen unit. Each one has its own LLVM
@@ -110,11 +117,11 @@ pub(crate) struct FullCx<'ll, 'tcx> {
 
     /// Statics that will be placed in the llvm.used variable
     /// See <https://llvm.org/docs/LangRef.html#the-llvm-used-global-variable> for details
-    pub used_statics: RefCell<Vec<&'ll Value>>,
+    pub used_statics: Vec<&'ll Value>,
 
     /// Statics that will be placed in the llvm.compiler.used variable
     /// See <https://llvm.org/docs/LangRef.html#the-llvm-compiler-used-global-variable> for details
-    pub compiler_used_statics: RefCell<Vec<&'ll Value>>,
+    pub compiler_used_statics: Vec<&'ll Value>,
 
     /// Mapping of non-scalar types to llvm types.
     pub type_lowering: RefCell<FxHashMap<(Ty<'tcx>, Option<VariantIdx>), &'ll Type>>,
@@ -606,8 +613,8 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
                 const_str_cache: Default::default(),
                 const_globals: Default::default(),
                 statics_to_rauw: RefCell::new(Vec::new()),
-                used_statics: RefCell::new(Vec::new()),
-                compiler_used_statics: RefCell::new(Vec::new()),
+                used_statics: Vec::new(),
+                compiler_used_statics: Vec::new(),
                 type_lowering: Default::default(),
                 scalar_lltypes: Default::default(),
                 coverage_cx,

compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -27,7 +27,7 @@ mod unused;
 ///
 /// Those sections are then read and understood by LLVM's `llvm-cov` tool,
 /// which is distributed in the `llvm-tools` rustup component.
-pub(crate) fn finalize(cx: &CodegenCx<'_, '_>) {
+pub(crate) fn finalize(cx: &mut CodegenCx<'_, '_>) {
     let tcx = cx.tcx;
 
     // Ensure that LLVM is using a version of the coverage mapping format that
@@ -62,6 +62,7 @@ pub(crate) fn finalize(cx: &CodegenCx<'_, '_>) {
         .sorted_by_cached_key(|&instance| tcx.symbol_name(instance).name)
         .filter_map(|instance| prepare_covfun_record(tcx, instance, true))
         .collect::<Vec<_>>();
+    drop(instances_used);
 
     // In a single designated CGU, also prepare covfun records for functions
     // in this crate that were instrumented for coverage, but are unused.
@@ -206,7 +207,7 @@ impl VirtualFileMapping {
 /// Generates the contents of the covmap record for this CGU, which mostly
 /// consists of a header and a list of filenames. The record is then stored
 /// as a global variable in the `__llvm_covmap` section.
-fn generate_covmap_record<'ll>(cx: &CodegenCx<'ll, '_>, version: u32, filenames_buffer: &[u8]) {
+fn generate_covmap_record<'ll>(cx: &mut CodegenCx<'ll, '_>, version: u32, filenames_buffer: &[u8]) {
     // A covmap record consists of four target-endian u32 values, followed by
     // the encoded filenames table. Two of the header fields are unused in
     // modern versions of the LLVM coverage mapping format, and are always 0.

compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs

@@ -181,7 +181,7 @@ fn fill_region_tables<'tcx>(
 /// contains the function's coverage mapping data. The record is then stored
 /// as a global variable in the `__llvm_covfun` section.
 pub(crate) fn generate_covfun_record<'tcx>(
-    cx: &CodegenCx<'_, 'tcx>,
+    cx: &mut CodegenCx<'_, 'tcx>,
     global_file_table: &GlobalFileTable,
     covfun: &CovfunRecord<'tcx>,
 ) {

compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs

@@ -56,7 +56,7 @@ impl<'ll, 'tcx> CguCoverageContext<'ll, 'tcx> {
 }
 
 impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
-    pub(crate) fn coverageinfo_finalize(&self) {
+    pub(crate) fn coverageinfo_finalize(&mut self) {
         mapgen::finalize(self)
     }
 

compiler/rustc_codegen_ssa/src/traits/statics.rs

@@ -5,19 +5,19 @@ 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);
+    fn codegen_static(&mut 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);
+    fn add_used_global(&mut 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 add_compiler_used_global(&mut self, global: Self::Value);
 }
 
 pub trait StaticBuilderMethods: BackendTypes {