diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src/context.rs')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/context.rs | 46 |
1 files changed, 29 insertions, 17 deletions
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index 9c0220d3448..35c866d48a4 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -71,9 +71,13 @@ pub struct CodegenCx<'ll, 'tcx> { /// to constants.) pub statics_to_rauw: RefCell<Vec<(&'ll Value, &'ll Value)>>, + /// 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>>, + /// 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 used_statics: RefCell<Vec<&'ll Value>>, + pub compiler_used_statics: RefCell<Vec<&'ll Value>>, /// Mapping of non-scalar types to llvm types and field remapping if needed. pub type_lowering: RefCell<FxHashMap<(Ty<'tcx>, Option<VariantIdx>), TypeLowering<'ll>>>, @@ -325,6 +329,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> { const_globals: Default::default(), statics_to_rauw: RefCell::new(Vec::new()), used_statics: RefCell::new(Vec::new()), + compiler_used_statics: RefCell::new(Vec::new()), type_lowering: Default::default(), scalar_lltypes: Default::default(), pointee_infos: Default::default(), @@ -347,6 +352,18 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> { pub fn coverage_context(&'a self) -> Option<&'a coverageinfo::CrateCoverageContext<'ll, 'tcx>> { self.coverage_cx.as_ref() } + + fn create_used_variable_impl(&self, name: &'static CStr, values: &[&'ll Value]) { + let section = cstr!("llvm.metadata"); + let array = self.const_array(&self.type_ptr_to(self.type_i8()), values); + + unsafe { + let g = llvm::LLVMAddGlobal(self.llmod, self.val_ty(array), name.as_ptr()); + llvm::LLVMSetInitializer(g, array); + llvm::LLVMRustSetLinkage(g, llvm::Linkage::AppendingLinkage); + llvm::LLVMSetSection(g, section.as_ptr()); + } + } } impl MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> { @@ -437,6 +454,10 @@ impl MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> { &self.used_statics } + fn compiler_used_statics(&self) -> &RefCell<Vec<&'ll Value>> { + &self.compiler_used_statics + } + fn set_frame_pointer_type(&self, llfn: &'ll Value) { attributes::set_frame_pointer_type(self, llfn) } @@ -447,23 +468,14 @@ impl MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> { } fn create_used_variable(&self) { - // The semantics of #[used] in Rust only require the symbol to make it into the object - // file. It is explicitly allowed for the linker to strip the symbol if it is dead. - // As such, use llvm.compiler.used instead of llvm.used. - // Additionally, https://reviews.llvm.org/D97448 in LLVM 13 started emitting unique - // sections with SHF_GNU_RETAIN flag for llvm.used symbols, which may trigger bugs in - // some versions of the gold linker. - let name = cstr!("llvm.compiler.used"); - let section = cstr!("llvm.metadata"); - let array = - self.const_array(&self.type_ptr_to(self.type_i8()), &*self.used_statics.borrow()); + self.create_used_variable_impl(cstr!("llvm.used"), &*self.used_statics.borrow()); + } - unsafe { - let g = llvm::LLVMAddGlobal(self.llmod, self.val_ty(array), name.as_ptr()); - llvm::LLVMSetInitializer(g, array); - llvm::LLVMRustSetLinkage(g, llvm::Linkage::AppendingLinkage); - llvm::LLVMSetSection(g, section.as_ptr()); - } + fn create_compiler_used_variable(&self) { + self.create_used_variable_impl( + cstr!("llvm.compiler.used"), + &*self.compiler_used_statics.borrow(), + ); } fn declare_c_main(&self, fn_type: Self::Type) -> Option<Self::Function> { |