Improve code readability

Author: GuillaumeGomez

Diff for: src/abi.rs

@@ -96,22 +96,30 @@ impl GccType for Reg {
     }
 }
 
+pub struct FnAbiGcc<'gcc> {
+    pub return_type: Type<'gcc>,
+    pub arguments_type: Vec<Type<'gcc>>,
+    pub is_c_variadic: bool,
+    pub on_stack_param_indices: FxHashSet<usize>,
+    pub fn_attributes: Vec<FnAttribute<'gcc>>,
+}
+
 pub trait FnAbiGccExt<'gcc, 'tcx> {
     // TODO(antoyo): return a function pointer type instead?
-    fn gcc_type(&self, cx: &CodegenCx<'gcc, 'tcx>) -> (Type<'gcc>, Vec<Type<'gcc>>, bool, FxHashSet<usize>, Vec<FnAttribute<'gcc>>);
+    fn gcc_type(&self, cx: &CodegenCx<'gcc, 'tcx>) -> FnAbiGcc<'gcc>;
     fn ptr_to_gcc_type(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc>;
 }
 
 impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
-    fn gcc_type(&self, cx: &CodegenCx<'gcc, 'tcx>) -> (Type<'gcc>, Vec<Type<'gcc>>, bool, FxHashSet<usize>, Vec<FnAttribute<'gcc>>) {
+    fn gcc_type(&self, cx: &CodegenCx<'gcc, 'tcx>) -> FnAbiGcc<'gcc> {
         let mut on_stack_param_indices = FxHashSet::default();
 
         // This capacity calculation is approximate.
         let mut argument_tys = Vec::with_capacity(
             self.args.len() + if let PassMode::Indirect { .. } = self.ret.mode { 1 } else { 0 }
         );
 
-        let return_ty =
+        let return_type =
             match self.ret.mode {
                 PassMode::Ignore => cx.type_void(),
                 PassMode::Direct(_) | PassMode::Pair(..) => self.ret.layout.immediate_gcc_type(cx),
@@ -185,13 +193,25 @@ impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
         #[cfg(not(feature = "master"))]
         let fn_attrs = Vec::new();
 
-        (return_ty, argument_tys, self.c_variadic, on_stack_param_indices, fn_attrs)
+        FnAbiGcc {
+            return_type,
+            arguments_type: argument_tys,
+            is_c_variadic: self.c_variadic,
+            on_stack_param_indices,
+            fn_attributes: fn_attrs,
+        }
     }
 
     fn ptr_to_gcc_type(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc> {
-        // FIXME: Should we do something with `fn_attrs`?
-        let (return_type, params, variadic, on_stack_param_indices, _fn_attrs) = self.gcc_type(cx);
-        let pointer_type = cx.context.new_function_pointer_type(None, return_type, &params, variadic);
+        // FIXME(antoyo): Should we do something with `FnAbiGcc::fn_attributes`?
+        let FnAbiGcc {
+            return_type,
+            arguments_type,
+            is_c_variadic,
+            on_stack_param_indices,
+            ..
+        } = self.gcc_type(cx);
+        let pointer_type = cx.context.new_function_pointer_type(None, return_type, &arguments_type, is_c_variadic);
         cx.on_stack_params.borrow_mut().insert(pointer_type.dyncast_function_ptr_type().expect("function ptr type"), on_stack_param_indices);
         pointer_type
     }

Diff for: src/declare.rs

@@ -6,7 +6,7 @@ use rustc_middle::ty::Ty;
 use rustc_span::Symbol;
 use rustc_target::abi::call::FnAbi;
 
-use crate::abi::FnAbiGccExt;
+use crate::abi::{FnAbiGcc, FnAbiGccExt};
 use crate::context::CodegenCx;
 use crate::intrinsic::llvm;
 
@@ -80,11 +80,16 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
     }
 
     pub fn declare_fn(&self, name: &str, fn_abi: &FnAbi<'tcx, Ty<'tcx>>) -> Function<'gcc> {
-        let (return_type, params, variadic, on_stack_param_indices, fn_attrs) = fn_abi.gcc_type(self);
-        let func = declare_raw_fn(self, name, () /*fn_abi.llvm_cconv()*/, return_type, &params, variadic);
+        let FnAbiGcc {
+            return_type,
+            arguments_type,
+            is_c_variadic,
+            on_stack_param_indices,
+            fn_attributes,
+        } = fn_abi.gcc_type(self);
+        let func = declare_raw_fn(self, name, () /*fn_abi.llvm_cconv()*/, return_type, &arguments_type, is_c_variadic);
         self.on_stack_function_params.borrow_mut().insert(func, on_stack_param_indices);
-        // We need to handle `nonnull` here where we still have access to function args.
-        for fn_attr in fn_attrs {
+        for fn_attr in fn_attributes {
             func.add_attribute(fn_attr);
         }
         func

Diff for: src/intrinsic/mod.rs

@@ -1197,7 +1197,7 @@ fn get_rust_try_fn<'a, 'gcc, 'tcx>(cx: &'a CodegenCx<'gcc, 'tcx>, codegen: &mut
 #[cfg(feature="master")]
 fn gen_fn<'a, 'gcc, 'tcx>(cx: &'a CodegenCx<'gcc, 'tcx>, name: &str, rust_fn_sig: ty::PolyFnSig<'tcx>, codegen: &mut dyn FnMut(Builder<'a, 'gcc, 'tcx>)) -> (Type<'gcc>, Function<'gcc>) {
     let fn_abi = cx.fn_abi_of_fn_ptr(rust_fn_sig, ty::List::empty());
-    let (typ, _, _, _, _) = fn_abi.gcc_type(cx);
+    let return_type = fn_abi.gcc_type(cx).return_type;
     // FIXME(eddyb) find a nicer way to do this.
     cx.linkage.set(FunctionType::Internal);
     let func = cx.declare_fn(name, fn_abi);
@@ -1207,5 +1207,5 @@ fn gen_fn<'a, 'gcc, 'tcx>(cx: &'a CodegenCx<'gcc, 'tcx>, name: &str, rust_fn_sig
     let block = Builder::append_block(cx, func_val, "entry-block");
     let bx = Builder::build(cx, block);
     codegen(bx);
-    (typ, func)
+    (return_type, func)
 }

Diff for: src/type_of.rs

@@ -9,7 +9,7 @@ use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_target::abi::{self, Abi, Align, F32, F64, FieldsShape, Int, Integer, Pointer, PointeeInfo, Size, TyAbiInterface, Variants};
 use rustc_target::abi::call::{CastTarget, FnAbi, Reg};
 
-use crate::abi::{FnAbiGccExt, GccType};
+use crate::abi::{FnAbiGcc, FnAbiGccExt, GccType};
 use crate::context::CodegenCx;
 use crate::type_::struct_fields;
 
@@ -372,8 +372,13 @@ impl<'gcc, 'tcx> LayoutTypeMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     }
 
     fn fn_decl_backend_type(&self, fn_abi: &FnAbi<'tcx, Ty<'tcx>>) -> Type<'gcc> {
-        // // FIXME: Should we do something with `fn_attrs`?
-        let (return_type, param_types, variadic, _, _fn_attrs) = fn_abi.gcc_type(self);
-        self.context.new_function_pointer_type(None, return_type, &param_types, variadic)
+        // FIXME(antoyo): Should we do something with `FnAbiGcc::fn_attributes`?
+        let FnAbiGcc {
+            return_type,
+            arguments_type,
+            is_c_variadic,
+            ..
+        } = fn_abi.gcc_type(self);
+        self.context.new_function_pointer_type(None, return_type, &arguments_type, is_c_variadic)
     }
 }