Add 'compiler/rustc_codegen_gcc/' from commit 'afae271d5d3719eeb92c18bc004bb6d1965a5f3f'

git-subtree-dir: compiler/rustc_codegen_gcc
git-subtree-mainline: ae90dcf020
git-subtree-split: afae271d5d

compiler/rustc_codegen_gcc/src/mono_item.rs

@@ -0,0 +1,59 @@
+use rustc_codegen_ssa::traits::PreDefineMethods;
+use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
+use rustc_middle::mir::mono::{Linkage, Visibility};
+use rustc_middle::ty::{self, Instance, TypeFoldable};
+use rustc_middle::ty::layout::FnAbiExt;
+use rustc_span::def_id::DefId;
+use rustc_target::abi::LayoutOf;
+use rustc_target::abi::call::FnAbi;
+
+use crate::base;
+use crate::context::CodegenCx;
+use crate::type_of::LayoutGccExt;
+
+impl<'gcc, 'tcx> PreDefineMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+    fn predefine_static(&self, def_id: DefId, _linkage: Linkage, _visibility: Visibility, symbol_name: &str) {
+        let attrs = self.tcx.codegen_fn_attrs(def_id);
+        let instance = Instance::mono(self.tcx, def_id);
+        let ty = instance.ty(self.tcx, ty::ParamEnv::reveal_all());
+        let gcc_type = self.layout_of(ty).gcc_type(self, true);
+
+        let is_tls = attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL);
+        let global = self.define_global(symbol_name, gcc_type, is_tls, attrs.link_section).unwrap_or_else(|| {
+            self.sess().span_fatal(
+                self.tcx.def_span(def_id),
+                &format!("symbol `{}` is already defined", symbol_name),
+            )
+        });
+
+        // TODO
+        /*unsafe {
+            llvm::LLVMRustSetLinkage(global, base::linkage_to_llvm(linkage));
+            llvm::LLVMRustSetVisibility(global, base::visibility_to_llvm(visibility));
+        }*/
+
+        self.instances.borrow_mut().insert(instance, global);
+    }
+
+    fn predefine_fn(&self, instance: Instance<'tcx>, linkage: Linkage, _visibility: Visibility, symbol_name: &str) {
+        assert!(!instance.substs.needs_infer() && !instance.substs.has_param_types_or_consts());
+
+        let fn_abi = FnAbi::of_instance(self, instance, &[]);
+        self.linkage.set(base::linkage_to_gcc(linkage));
+        let _decl = self.declare_fn(symbol_name, &fn_abi);
+        //let attrs = self.tcx.codegen_fn_attrs(instance.def_id());
+
+        // TODO: call set_link_section() to allow initializing argc/argv.
+        //base::set_link_section(decl, &attrs);
+        /*if linkage == Linkage::LinkOnceODR || linkage == Linkage::WeakODR {
+            llvm::SetUniqueComdat(self.llmod, decl);
+        }*/
+
+        //debug!("predefine_fn: instance = {:?}", instance);
+
+        // TODO: use inline attribute from there in linkage.set() above:
+        //attributes::from_fn_attrs(self, decl, instance);
+
+        //self.instances.borrow_mut().insert(instance, decl);
+    }
+}