Rollup merge of #130457 - nnethercote:cleanup-codegen-traits, r=bjorn3

Cleanup codegen traits

The traits governing codegen are quite complicated and hard to follow. This PR cleans them up a bit.

r? `@bjorn3`

compiler/rustc_codegen_cranelift/src/common.rs

@@ -309,8 +309,6 @@ pub(crate) struct FunctionCx<'m, 'clif, 'tcx: 'm> {
 }
 
 impl<'tcx> LayoutOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         RevealAllLayoutCx(self.tcx).handle_layout_err(err, span, ty)
@@ -318,8 +316,6 @@ impl<'tcx> LayoutOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> {
 }
 
 impl<'tcx> FnAbiOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> {
-    type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
-
     #[inline]
     fn handle_fn_abi_err(
         &self,
@@ -450,8 +446,6 @@ impl<'tcx> FunctionCx<'_, '_, 'tcx> {
 pub(crate) struct RevealAllLayoutCx<'tcx>(pub(crate) TyCtxt<'tcx>);
 
 impl<'tcx> LayoutOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         if let LayoutError::SizeOverflow(_) | LayoutError::ReferencesError(_) = err {
@@ -466,8 +460,6 @@ impl<'tcx> LayoutOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
 }
 
 impl<'tcx> FnAbiOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
-    type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
-
     #[inline]
     fn handle_fn_abi_err(
         &self,

compiler/rustc_codegen_gcc/src/abi.rs

@@ -1,7 +1,7 @@
 #[cfg(feature = "master")]
 use gccjit::FnAttribute;
 use gccjit::{ToLValue, ToRValue, Type};
-use rustc_codegen_ssa::traits::{AbiBuilderMethods, BaseTypeMethods};
+use rustc_codegen_ssa::traits::{AbiBuilderMethods, BaseTypeCodegenMethods};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::LayoutOf;

compiler/rustc_codegen_gcc/src/asm.rs

@@ -5,8 +5,8 @@ use rustc_ast::ast::{InlineAsmOptions, InlineAsmTemplatePiece};
 use rustc_codegen_ssa::mir::operand::OperandValue;
 use rustc_codegen_ssa::mir::place::PlaceRef;
 use rustc_codegen_ssa::traits::{
-    AsmBuilderMethods, AsmMethods, BaseTypeMethods, BuilderMethods, GlobalAsmOperandRef,
-    InlineAsmOperandRef,
+    AsmBuilderMethods, AsmCodegenMethods, BaseTypeCodegenMethods, BuilderMethods,
+    GlobalAsmOperandRef, InlineAsmOperandRef,
 };
 use rustc_middle::bug;
 use rustc_middle::ty::Instance;
@@ -770,7 +770,7 @@ fn dummy_output_type<'gcc, 'tcx>(cx: &CodegenCx<'gcc, 'tcx>, reg: InlineAsmRegCl
     }
 }
 
-impl<'gcc, 'tcx> AsmMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> AsmCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn codegen_global_asm(
         &self,
         template: &[InlineAsmTemplatePiece],

compiler/rustc_codegen_gcc/src/base.rs

@@ -6,7 +6,7 @@ use std::time::Instant;
 use gccjit::{CType, FunctionType, GlobalKind};
 use rustc_codegen_ssa::base::maybe_create_entry_wrapper;
 use rustc_codegen_ssa::mono_item::MonoItemExt;
-use rustc_codegen_ssa::traits::DebugInfoMethods;
+use rustc_codegen_ssa::traits::DebugInfoCodegenMethods;
 use rustc_codegen_ssa::{ModuleCodegen, ModuleKind};
 use rustc_middle::dep_graph;
 use rustc_middle::mir::mono::Linkage;

compiler/rustc_codegen_gcc/src/builder.rs

@@ -14,8 +14,8 @@ use rustc_codegen_ssa::common::{
 use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
 use rustc_codegen_ssa::mir::place::PlaceRef;
 use rustc_codegen_ssa::traits::{
-    BackendTypes, BaseTypeMethods, BuilderMethods, ConstMethods, HasCodegen, LayoutTypeMethods,
-    OverflowOp, StaticBuilderMethods,
+    BackendTypes, BaseTypeCodegenMethods, BuilderMethods, ConstCodegenMethods,
+    LayoutTypeCodegenMethods, OverflowOp, StaticBuilderMethods,
 };
 use rustc_codegen_ssa::MemFlags;
 use rustc_data_structures::fx::FxHashSet;
@@ -23,7 +23,6 @@ use rustc_middle::bug;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers,
-    TyAndLayout,
 };
 use rustc_middle::ty::{Instance, ParamEnv, Ty, TyCtxt};
 use rustc_span::def_id::DefId;
@@ -460,10 +459,6 @@ impl<'a, 'gcc, 'tcx> Builder<'a, 'gcc, 'tcx> {
     }
 }
 
-impl<'gcc, 'tcx> HasCodegen<'tcx> for Builder<'_, 'gcc, 'tcx> {
-    type CodegenCx = CodegenCx<'gcc, 'tcx>;
-}
-
 impl<'tcx> HasTyCtxt<'tcx> for Builder<'_, '_, 'tcx> {
     fn tcx(&self) -> TyCtxt<'tcx> {
         self.cx.tcx()
@@ -477,8 +472,6 @@ impl HasDataLayout for Builder<'_, '_, '_> {
 }
 
 impl<'tcx> LayoutOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         self.cx.handle_layout_err(err, span, ty)
@@ -486,8 +479,6 @@ impl<'tcx> LayoutOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
 }
 
 impl<'tcx> FnAbiOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
-    type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
-
     #[inline]
     fn handle_fn_abi_err(
         &self,
@@ -531,6 +522,8 @@ fn set_rvalue_location<'a, 'gcc, 'tcx>(
 }
 
 impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
+    type CodegenCx = CodegenCx<'gcc, 'tcx>;
+
     fn build(cx: &'a CodegenCx<'gcc, 'tcx>, block: Block<'gcc>) -> Builder<'a, 'gcc, 'tcx> {
         Builder::with_cx(cx, block)
     }

compiler/rustc_codegen_gcc/src/common.rs

@@ -1,5 +1,7 @@
 use gccjit::{LValue, RValue, ToRValue, Type};
-use rustc_codegen_ssa::traits::{BaseTypeMethods, ConstMethods, MiscMethods, StaticMethods};
+use rustc_codegen_ssa::traits::{
+    BaseTypeCodegenMethods, ConstCodegenMethods, MiscCodegenMethods, StaticCodegenMethods,
+};
 use rustc_middle::mir::interpret::{ConstAllocation, GlobalAlloc, Scalar};
 use rustc_middle::mir::Mutability;
 use rustc_middle::ty::layout::LayoutOf;
@@ -55,7 +57,7 @@ pub fn type_is_pointer(typ: Type<'_>) -> bool {
     typ.get_pointee().is_some()
 }
 
-impl<'gcc, 'tcx> ConstMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> ConstCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn const_null(&self, typ: Type<'gcc>) -> RValue<'gcc> {
         if type_is_pointer(typ) { self.context.new_null(typ) } else { self.const_int(typ, 0) }
     }

compiler/rustc_codegen_gcc/src/consts.rs

@@ -1,7 +1,9 @@
 #[cfg(feature = "master")]
 use gccjit::{FnAttribute, VarAttribute, Visibility};
 use gccjit::{Function, GlobalKind, LValue, RValue, ToRValue, Type};
-use rustc_codegen_ssa::traits::{BaseTypeMethods, ConstMethods, StaticMethods};
+use rustc_codegen_ssa::traits::{
+    BaseTypeCodegenMethods, ConstCodegenMethods, StaticCodegenMethods,
+};
 use rustc_hir::def::DefKind;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
 use rustc_middle::mir::interpret::{
@@ -37,7 +39,7 @@ fn set_global_alignment<'gcc, 'tcx>(
     gv.set_alignment(align.bytes() as i32);
 }
 
-impl<'gcc, 'tcx> StaticMethods for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> StaticCodegenMethods for CodegenCx<'gcc, 'tcx> {
     fn static_addr_of(&self, cv: RValue<'gcc>, align: Align, kind: Option<&str>) -> RValue<'gcc> {
         // TODO(antoyo): implement a proper rvalue comparison in libgccjit instead of doing the
         // following:

compiler/rustc_codegen_gcc/src/context.rs

@@ -5,20 +5,19 @@ use gccjit::{
 };
 use rustc_codegen_ssa::base::wants_msvc_seh;
 use rustc_codegen_ssa::errors as ssa_errors;
-use rustc_codegen_ssa::traits::{BackendTypes, BaseTypeMethods, MiscMethods};
+use rustc_codegen_ssa::traits::{BackendTypes, BaseTypeCodegenMethods, MiscCodegenMethods};
 use rustc_data_structures::base_n::{ToBaseN, ALPHANUMERIC_ONLY};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::span_bug;
 use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOf, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, HasTyCtxt, LayoutError,
-    LayoutOfHelpers, TyAndLayout,
+    LayoutOfHelpers,
 };
 use rustc_middle::ty::{self, Instance, ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_span::source_map::respan;
 use rustc_span::{Span, DUMMY_SP};
-use rustc_target::abi::call::FnAbi;
 use rustc_target::abi::{HasDataLayout, PointeeInfo, Size, TargetDataLayout, VariantIdx};
 use rustc_target::spec::{HasTargetSpec, HasWasmCAbiOpt, Target, TlsModel, WasmCAbi};
 
@@ -426,7 +425,7 @@ impl<'gcc, 'tcx> BackendTypes for CodegenCx<'gcc, 'tcx> {
     type DIVariable = (); // TODO(antoyo)
 }
 
-impl<'gcc, 'tcx> MiscMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn vtables(
         &self,
     ) -> &RefCell<FxHashMap<(Ty<'tcx>, Option<PolyExistentialTraitRef<'tcx>>), RValue<'gcc>>> {
@@ -572,8 +571,6 @@ impl<'gcc, 'tcx> HasWasmCAbiOpt for CodegenCx<'gcc, 'tcx> {
 }
 
 impl<'gcc, 'tcx> LayoutOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         if let LayoutError::SizeOverflow(_) | LayoutError::ReferencesError(_) = err {
@@ -585,8 +582,6 @@ impl<'gcc, 'tcx> LayoutOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
 }
 
 impl<'gcc, 'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
-    type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
-
     #[inline]
     fn handle_fn_abi_err(
         &self,

compiler/rustc_codegen_gcc/src/debuginfo.rs

@@ -2,7 +2,7 @@ use std::ops::Range;
 
 use gccjit::{Location, RValue};
 use rustc_codegen_ssa::mir::debuginfo::{DebugScope, FunctionDebugContext, VariableKind};
-use rustc_codegen_ssa::traits::{DebugInfoBuilderMethods, DebugInfoMethods};
+use rustc_codegen_ssa::traits::{DebugInfoBuilderMethods, DebugInfoCodegenMethods};
 use rustc_data_structures::sync::Lrc;
 use rustc_index::bit_set::BitSet;
 use rustc_index::{Idx, IndexVec};
@@ -206,7 +206,7 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
     }
 }
 
-impl<'gcc, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn create_vtable_debuginfo(
         &self,
         _ty: Ty<'tcx>,

compiler/rustc_codegen_gcc/src/declare.rs

@@ -1,7 +1,7 @@
 #[cfg(feature = "master")]
 use gccjit::{FnAttribute, ToRValue};
 use gccjit::{Function, FunctionType, GlobalKind, LValue, RValue, Type};
-use rustc_codegen_ssa::traits::BaseTypeMethods;
+use rustc_codegen_ssa::traits::BaseTypeCodegenMethods;
 use rustc_middle::ty::Ty;
 use rustc_span::Symbol;
 use rustc_target::abi::call::FnAbi;

compiler/rustc_codegen_gcc/src/int.rs

@@ -4,7 +4,7 @@
 
 use gccjit::{BinaryOp, ComparisonOp, FunctionType, Location, RValue, ToRValue, Type, UnaryOp};
 use rustc_codegen_ssa::common::{IntPredicate, TypeKind};
-use rustc_codegen_ssa::traits::{BackendTypes, BaseTypeMethods, BuilderMethods, OverflowOp};
+use rustc_codegen_ssa::traits::{BackendTypes, BaseTypeCodegenMethods, BuilderMethods, OverflowOp};
 use rustc_middle::ty::{ParamEnv, Ty};
 use rustc_target::abi::call::{ArgAbi, ArgAttributes, Conv, FnAbi, PassMode};
 use rustc_target::abi::Endian;

compiler/rustc_codegen_gcc/src/intrinsic/mod.rs

@@ -13,10 +13,10 @@ use rustc_codegen_ssa::errors::InvalidMonomorphization;
 use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
 use rustc_codegen_ssa::mir::place::{PlaceRef, PlaceValue};
 use rustc_codegen_ssa::traits::{
-    ArgAbiMethods, BuilderMethods, ConstMethods, IntrinsicCallMethods,
+    ArgAbiBuilderMethods, BuilderMethods, ConstCodegenMethods, IntrinsicCallBuilderMethods,
 };
 #[cfg(feature = "master")]
-use rustc_codegen_ssa::traits::{BaseTypeMethods, MiscMethods};
+use rustc_codegen_ssa::traits::{BaseTypeCodegenMethods, MiscCodegenMethods};
 use rustc_codegen_ssa::MemFlags;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::LayoutOf;
@@ -94,7 +94,7 @@ fn get_simple_intrinsic<'gcc, 'tcx>(
     Some(cx.context.get_builtin_function(gcc_name))
 }
 
-impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
+impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
     fn codegen_intrinsic_call(
         &mut self,
         instance: Instance<'tcx>,
@@ -448,7 +448,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
     }
 }
 
-impl<'a, 'gcc, 'tcx> ArgAbiMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
+impl<'a, 'gcc, 'tcx> ArgAbiBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
     fn store_fn_arg(
         &mut self,
         arg_abi: &ArgAbi<'tcx, Ty<'tcx>>,

compiler/rustc_codegen_gcc/src/intrinsic/simd.rs

@@ -10,7 +10,7 @@ use rustc_codegen_ssa::errors::ExpectedPointerMutability;
 use rustc_codegen_ssa::errors::InvalidMonomorphization;
 use rustc_codegen_ssa::mir::operand::OperandRef;
 use rustc_codegen_ssa::mir::place::PlaceRef;
-use rustc_codegen_ssa::traits::{BaseTypeMethods, BuilderMethods};
+use rustc_codegen_ssa::traits::{BaseTypeCodegenMethods, BuilderMethods};
 #[cfg(feature = "master")]
 use rustc_hir as hir;
 use rustc_middle::mir::BinOp;

compiler/rustc_codegen_gcc/src/mono_item.rs

@@ -1,6 +1,6 @@
 #[cfg(feature = "master")]
 use gccjit::{FnAttribute, VarAttribute};
-use rustc_codegen_ssa::traits::PreDefineMethods;
+use rustc_codegen_ssa::traits::PreDefineCodegenMethods;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
@@ -13,7 +13,7 @@ use crate::context::CodegenCx;
 use crate::type_of::LayoutGccExt;
 use crate::{attributes, base};
 
-impl<'gcc, 'tcx> PreDefineMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     #[cfg_attr(not(feature = "master"), allow(unused_variables))]
     fn predefine_static(
         &self,

compiler/rustc_codegen_gcc/src/type_.rs

@@ -5,7 +5,9 @@ use std::convert::TryInto;
 use gccjit::CType;
 use gccjit::{RValue, Struct, Type};
 use rustc_codegen_ssa::common::TypeKind;
-use rustc_codegen_ssa::traits::{BaseTypeMethods, DerivedTypeMethods, TypeMembershipMethods};
+use rustc_codegen_ssa::traits::{
+    BaseTypeCodegenMethods, DerivedTypeCodegenMethods, TypeMembershipCodegenMethods,
+};
 use rustc_middle::ty::layout::TyAndLayout;
 use rustc_middle::{bug, ty};
 use rustc_target::abi::{AddressSpace, Align, Integer, Size};
@@ -121,7 +123,7 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
     }
 }
 
-impl<'gcc, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> BaseTypeCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn type_i8(&self) -> Type<'gcc> {
         self.i8_type
     }
@@ -381,4 +383,4 @@ pub fn struct_fields<'gcc, 'tcx>(
     (result, packed)
 }
 
-impl<'gcc, 'tcx> TypeMembershipMethods<'tcx> for CodegenCx<'gcc, 'tcx> {}
+impl<'gcc, 'tcx> TypeMembershipCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {}

compiler/rustc_codegen_gcc/src/type_of.rs

@@ -1,7 +1,9 @@
 use std::fmt::Write;
 
 use gccjit::{Struct, Type};
-use rustc_codegen_ssa::traits::{BaseTypeMethods, DerivedTypeMethods, LayoutTypeMethods};
+use rustc_codegen_ssa::traits::{
+    BaseTypeCodegenMethods, DerivedTypeCodegenMethods, LayoutTypeCodegenMethods,
+};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
@@ -330,7 +332,7 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
     }
 }
 
-impl<'gcc, 'tcx> LayoutTypeMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
+impl<'gcc, 'tcx> LayoutTypeCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn backend_type(&self, layout: TyAndLayout<'tcx>) -> Type<'gcc> {
         layout.gcc_type(self)
     }

compiler/rustc_codegen_llvm/src/abi.rs

@@ -285,7 +285,7 @@ impl<'ll, 'tcx> ArgAbiExt<'ll, 'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
     }
 }
 
-impl<'ll, 'tcx> ArgAbiMethods<'tcx> for Builder<'_, 'll, 'tcx> {
+impl<'ll, 'tcx> ArgAbiBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
     fn store_fn_arg(
         &mut self,
         arg_abi: &ArgAbi<'tcx, Ty<'tcx>>,

compiler/rustc_codegen_llvm/src/asm.rs

@@ -356,7 +356,7 @@ impl<'ll, 'tcx> AsmBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
     }
 }
 
-impl<'tcx> AsmMethods<'tcx> for CodegenCx<'_, 'tcx> {
+impl<'tcx> AsmCodegenMethods<'tcx> for CodegenCx<'_, 'tcx> {
     fn codegen_global_asm(
         &self,
         template: &[InlineAsmTemplatePiece],

compiler/rustc_codegen_llvm/src/builder.rs

@@ -93,8 +93,6 @@ impl HasTargetSpec for Builder<'_, '_, '_> {
 }
 
 impl<'tcx> LayoutOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         self.cx.handle_layout_err(err, span, ty)
@@ -102,8 +100,6 @@ impl<'tcx> LayoutOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
 }
 
 impl<'tcx> FnAbiOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
-    type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
-
     #[inline]
     fn handle_fn_abi_err(
         &self,
@@ -124,10 +120,6 @@ impl<'ll, 'tcx> Deref for Builder<'_, 'll, 'tcx> {
     }
 }
 
-impl<'ll, 'tcx> HasCodegen<'tcx> for Builder<'_, 'll, 'tcx> {
-    type CodegenCx = CodegenCx<'ll, 'tcx>;
-}
-
 macro_rules! builder_methods_for_value_instructions {
     ($($name:ident($($arg:ident),*) => $llvm_capi:ident),+ $(,)?) => {
         $(fn $name(&mut self, $($arg: &'ll Value),*) -> &'ll Value {
@@ -139,6 +131,8 @@ macro_rules! builder_methods_for_value_instructions {
 }
 
 impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
+    type CodegenCx = CodegenCx<'ll, 'tcx>;
+
     fn build(cx: &'a CodegenCx<'ll, 'tcx>, llbb: &'ll BasicBlock) -> Self {
         let bx = Builder::with_cx(cx);
         unsafe {

compiler/rustc_codegen_llvm/src/common.rs

@@ -113,7 +113,7 @@ impl<'ll> CodegenCx<'ll, '_> {
     }
 }
 
-impl<'ll, 'tcx> ConstMethods<'tcx> for CodegenCx<'ll, 'tcx> {
+impl<'ll, 'tcx> ConstCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn const_null(&self, t: &'ll Type) -> &'ll Value {
         unsafe { llvm::LLVMConstNull(t) }
     }

compiler/rustc_codegen_llvm/src/consts.rs

@@ -565,7 +565,7 @@ impl<'ll> CodegenCx<'ll, '_> {
     }
 }
 
-impl<'ll> StaticMethods for CodegenCx<'ll, '_> {
+impl<'ll> StaticCodegenMethods for CodegenCx<'ll, '_> {
     fn static_addr_of(&self, cv: &'ll Value, align: Align, kind: Option<&str>) -> &'ll Value {
         if let Some(&gv) = self.const_globals.borrow().get(&cv) {
             unsafe {

compiler/rustc_codegen_llvm/src/context.rs

@@ -15,7 +15,6 @@ use rustc_middle::middle::codegen_fn_attrs::PatchableFunctionEntry;
 use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, LayoutError, LayoutOfHelpers,
-    TyAndLayout,
 };
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
@@ -25,7 +24,6 @@ use rustc_session::config::{
 use rustc_session::Session;
 use rustc_span::source_map::Spanned;
 use rustc_span::{Span, DUMMY_SP};
-use rustc_target::abi::call::FnAbi;
 use rustc_target::abi::{HasDataLayout, TargetDataLayout, VariantIdx};
 use rustc_target::spec::{HasTargetSpec, RelocModel, SmallDataThresholdSupport, Target, TlsModel};
 use smallvec::SmallVec;
@@ -598,7 +596,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
     }
 }
 
-impl<'ll, 'tcx> MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> {
+impl<'ll, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn vtables(
         &self,
     ) -> &RefCell<FxHashMap<(Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>), &'ll Value>>
@@ -1158,8 +1156,6 @@ impl<'tcx, 'll> HasParamEnv<'tcx> for CodegenCx<'ll, 'tcx> {
 }
 
 impl<'tcx> LayoutOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         if let LayoutError::SizeOverflow(_) | LayoutError::ReferencesError(_) = err {
@@ -1171,8 +1167,6 @@ impl<'tcx> LayoutOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
 }
 
 impl<'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
-    type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>;
-
     #[inline]
     fn handle_fn_abi_err(
         &self,

compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -1,5 +1,5 @@
 use itertools::Itertools as _;
-use rustc_codegen_ssa::traits::{BaseTypeMethods, ConstMethods};
+use rustc_codegen_ssa::traits::{BaseTypeCodegenMethods, ConstCodegenMethods};
 use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_index::IndexVec;

compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs

@@ -2,8 +2,8 @@ use std::cell::RefCell;
 
 use libc::c_uint;
 use rustc_codegen_ssa::traits::{
-    BaseTypeMethods, BuilderMethods, ConstMethods, CoverageInfoBuilderMethods, MiscMethods,
-    StaticMethods,
+    BaseTypeCodegenMethods, BuilderMethods, ConstCodegenMethods, CoverageInfoBuilderMethods,
+    MiscCodegenMethods, StaticCodegenMethods,
 };
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
 use rustc_llvm::RustString;

compiler/rustc_codegen_llvm/src/debuginfo/metadata/enums/cpp_like.rs

@@ -3,7 +3,7 @@ use std::borrow::Cow;
 use libc::c_uint;
 use rustc_codegen_ssa::debuginfo::type_names::compute_debuginfo_type_name;
 use rustc_codegen_ssa::debuginfo::{tag_base_type, wants_c_like_enum_debuginfo};
-use rustc_codegen_ssa::traits::ConstMethods;
+use rustc_codegen_ssa::traits::ConstCodegenMethods;
 use rustc_index::IndexVec;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};

compiler/rustc_codegen_llvm/src/debuginfo/metadata/enums/native.rs

@@ -3,7 +3,7 @@ use std::borrow::Cow;
 use libc::c_uint;
 use rustc_codegen_ssa::debuginfo::type_names::compute_debuginfo_type_name;
 use rustc_codegen_ssa::debuginfo::{tag_base_type, wants_c_like_enum_debuginfo};
-use rustc_codegen_ssa::traits::ConstMethods;
+use rustc_codegen_ssa::traits::ConstCodegenMethods;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
 use rustc_middle::ty::{self};

compiler/rustc_codegen_llvm/src/debuginfo/mod.rs

@@ -286,7 +286,7 @@ impl CodegenCx<'_, '_> {
     }
 }
 
-impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
+impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn create_function_debug_context(
         &self,
         instance: Instance<'tcx>,

compiler/rustc_codegen_llvm/src/declare.rs

@@ -12,7 +12,7 @@
 //! * When in doubt, define.
 
 use itertools::Itertools;
-use rustc_codegen_ssa::traits::TypeMembershipMethods;
+use rustc_codegen_ssa::traits::TypeMembershipCodegenMethods;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_middle::ty::{Instance, Ty};
 use rustc_sanitizers::{cfi, kcfi};

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -148,7 +148,7 @@ fn get_simple_intrinsic<'ll>(
     Some(cx.get_intrinsic(llvm_name))
 }
 
-impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> {
+impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
     fn codegen_intrinsic_call(
         &mut self,
         instance: ty::Instance<'tcx>,

compiler/rustc_codegen_llvm/src/mono_item.rs

@@ -14,7 +14,7 @@ use crate::errors::SymbolAlreadyDefined;
 use crate::type_of::LayoutLlvmExt;
 use crate::{base, llvm};
 
-impl<'tcx> PreDefineMethods<'tcx> for CodegenCx<'_, 'tcx> {
+impl<'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'_, 'tcx> {
     fn predefine_static(
         &self,
         def_id: DefId,

compiler/rustc_codegen_llvm/src/type_.rs

@@ -141,7 +141,7 @@ impl<'ll> CodegenCx<'ll, '_> {
     }
 }
 
-impl<'ll, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'ll, 'tcx> {
+impl<'ll, 'tcx> BaseTypeCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn type_i8(&self) -> &'ll Type {
         unsafe { llvm::LLVMInt8TypeInContext(self.llcx) }
     }
@@ -245,7 +245,7 @@ impl Type {
     }
 }
 
-impl<'ll, 'tcx> LayoutTypeMethods<'tcx> for CodegenCx<'ll, 'tcx> {
+impl<'ll, 'tcx> LayoutTypeCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn backend_type(&self, layout: TyAndLayout<'tcx>) -> &'ll Type {
         layout.llvm_type(self)
     }
@@ -280,7 +280,7 @@ impl<'ll, 'tcx> LayoutTypeMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     }
 }
 
-impl<'ll, 'tcx> TypeMembershipMethods<'tcx> for CodegenCx<'ll, 'tcx> {
+impl<'ll, 'tcx> TypeMembershipCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn add_type_metadata(&self, function: &'ll Value, typeid: String) {
         let typeid_metadata = self.typeid_metadata(typeid).unwrap();
         let v = [self.const_usize(0), typeid_metadata];

compiler/rustc_codegen_llvm/src/va_arg.rs

@@ -1,6 +1,6 @@
 use rustc_codegen_ssa::common::IntPredicate;
 use rustc_codegen_ssa::mir::operand::OperandRef;
-use rustc_codegen_ssa::traits::{BaseTypeMethods, BuilderMethods, ConstMethods};
+use rustc_codegen_ssa::traits::{BaseTypeCodegenMethods, BuilderMethods, ConstCodegenMethods};
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf};
 use rustc_middle::ty::Ty;
 use rustc_target::abi::{Align, Endian, HasDataLayout, Size};

compiler/rustc_codegen_ssa/src/lib.rs

@@ -11,6 +11,7 @@
 #![feature(negative_impls)]
 #![feature(rustdoc_internals)]
 #![feature(strict_provenance)]
+#![feature(trait_alias)]
 #![feature(try_blocks)]
 #![warn(unreachable_pub)]
 // tidy-alphabetical-end

compiler/rustc_codegen_ssa/src/mir/operand.rs

@@ -27,32 +27,32 @@ pub enum OperandValue<V> {
     /// which indicates that it refers to an unsized rvalue.
     ///
     /// An `OperandValue` *must* be this variant for any type for which
-    /// [`LayoutTypeMethods::is_backend_ref`] returns `true`.
+    /// [`LayoutTypeCodegenMethods::is_backend_ref`] returns `true`.
     /// (That basically amounts to "isn't one of the other variants".)
     ///
     /// This holds a [`PlaceValue`] (like a [`PlaceRef`] does) with a pointer
     /// to the location holding the value. The type behind that pointer is the
-    /// one returned by [`LayoutTypeMethods::backend_type`].
+    /// one returned by [`LayoutTypeCodegenMethods::backend_type`].
     Ref(PlaceValue<V>),
     /// A single LLVM immediate value.
     ///
     /// An `OperandValue` *must* be this variant for any type for which
-    /// [`LayoutTypeMethods::is_backend_immediate`] returns `true`.
+    /// [`LayoutTypeCodegenMethods::is_backend_immediate`] returns `true`.
     /// The backend value in this variant must be the *immediate* backend type,
-    /// as returned by [`LayoutTypeMethods::immediate_backend_type`].
+    /// as returned by [`LayoutTypeCodegenMethods::immediate_backend_type`].
     Immediate(V),
     /// A pair of immediate LLVM values. Used by fat pointers too.
     ///
     /// An `OperandValue` *must* be this variant for any type for which
-    /// [`LayoutTypeMethods::is_backend_scalar_pair`] returns `true`.
+    /// [`LayoutTypeCodegenMethods::is_backend_scalar_pair`] returns `true`.
     /// The backend values in this variant must be the *immediate* backend types,
-    /// as returned by [`LayoutTypeMethods::scalar_pair_element_backend_type`]
+    /// as returned by [`LayoutTypeCodegenMethods::scalar_pair_element_backend_type`]
     /// with `immediate: true`.
     Pair(V, V),
     /// A value taking no bytes, and which therefore needs no LLVM value at all.
     ///
     /// If you ever need a `V` to pass to something, get a fresh poison value
-    /// from [`ConstMethods::const_poison`].
+    /// from [`ConstCodegenMethods::const_poison`].
     ///
     /// An `OperandValue` *must* be this variant for any type for which
     /// `is_zst` on its `Layout` returns `true`. Note however that
@@ -110,7 +110,7 @@ impl<V: CodegenObject> OperandValue<V> {
         PlaceValue { llval, llextra, align }
     }
 
-    pub(crate) fn is_expected_variant_for_type<'tcx, Cx: LayoutTypeMethods<'tcx>>(
+    pub(crate) fn is_expected_variant_for_type<'tcx, Cx: LayoutTypeCodegenMethods<'tcx>>(
         &self,
         cx: &Cx,
         ty: TyAndLayout<'tcx>,
@@ -280,7 +280,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
     ///
     /// If you don't need the type, see [`OperandValue::pointer_parts`]
     /// or [`OperandValue::deref`].
-    pub fn deref<Cx: LayoutTypeMethods<'tcx>>(self, cx: &Cx) -> PlaceRef<'tcx, V> {
+    pub fn deref<Cx: CodegenMethods<'tcx>>(self, cx: &Cx) -> PlaceRef<'tcx, V> {
         if self.layout.ty.is_box() {
             // Derefer should have removed all Box derefs
             bug!("dereferencing {:?} in codegen", self.layout.ty);

compiler/rustc_codegen_ssa/src/mir/place.rs

@@ -133,7 +133,7 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
         Self::alloca(bx, ptr_layout)
     }
 
-    pub fn len<Cx: ConstMethods<'tcx, Value = V>>(&self, cx: &Cx) -> V {
+    pub fn len<Cx: ConstCodegenMethods<'tcx, Value = V>>(&self, cx: &Cx) -> V {
         if let FieldsShape::Array { count, .. } = self.layout.fields {
             if self.layout.is_unsized() {
                 assert_eq!(count, 0);

compiler/rustc_codegen_ssa/src/traits/asm.rs

@@ -60,7 +60,7 @@ pub trait AsmBuilderMethods<'tcx>: BackendTypes {
     );
 }
 
-pub trait AsmMethods<'tcx> {
+pub trait AsmCodegenMethods<'tcx> {
     fn codegen_global_asm(
         &self,
         template: &[InlineAsmTemplatePiece],

compiler/rustc_codegen_ssa/src/traits/backend.rs

@@ -8,13 +8,11 @@ use rustc_errors::ErrorGuaranteed;
 use rustc_metadata::creader::MetadataLoaderDyn;
 use rustc_metadata::EncodedMetadata;
 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, LayoutOf, TyAndLayout};
-use rustc_middle::ty::{Ty, TyCtxt};
+use rustc_middle::ty::TyCtxt;
 use rustc_middle::util::Providers;
 use rustc_session::config::{self, OutputFilenames, PrintRequest};
 use rustc_session::Session;
 use rustc_span::symbol::Symbol;
-use rustc_target::abi::call::FnAbi;
 
 use super::write::WriteBackendMethods;
 use super::CodegenObject;
@@ -36,23 +34,6 @@ pub trait BackendTypes {
     type DIVariable: Copy;
 }
 
-pub trait Backend<'tcx>:
-    Sized
-    + BackendTypes
-    + HasTyCtxt<'tcx>
-    + LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
-    + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
-{
-}
-
-impl<'tcx, T> Backend<'tcx> for T where
-    Self: BackendTypes
-        + HasTyCtxt<'tcx>
-        + LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
-        + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
-{
-}
-
 pub trait CodegenBackend {
     /// Locale resources for diagnostic messages - a string the content of the Fluent resource.
     /// Called before `init` so that all other functions are able to emit translatable diagnostics.

compiler/rustc_codegen_ssa/src/traits/builder.rs

@@ -1,23 +1,23 @@
 use std::assert_matches::assert_matches;
+use std::ops::Deref;
 
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
-use rustc_middle::ty::layout::{HasParamEnv, TyAndLayout};
+use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{Instance, Ty};
 use rustc_session::config::OptLevel;
 use rustc_span::Span;
 use rustc_target::abi::call::FnAbi;
 use rustc_target::abi::{Abi, Align, Scalar, Size, WrappingRange};
-use rustc_target::spec::HasTargetSpec;
 
 use super::abi::AbiBuilderMethods;
 use super::asm::AsmBuilderMethods;
-use super::consts::ConstMethods;
+use super::consts::ConstCodegenMethods;
 use super::coverageinfo::CoverageInfoBuilderMethods;
 use super::debuginfo::DebugInfoBuilderMethods;
-use super::intrinsic::IntrinsicCallMethods;
-use super::misc::MiscMethods;
-use super::type_::{ArgAbiMethods, BaseTypeMethods, LayoutTypeMethods};
-use super::{HasCodegen, StaticBuilderMethods};
+use super::intrinsic::IntrinsicCallBuilderMethods;
+use super::misc::MiscCodegenMethods;
+use super::type_::{ArgAbiBuilderMethods, BaseTypeCodegenMethods, LayoutTypeCodegenMethods};
+use super::{CodegenMethods, StaticBuilderMethods};
 use crate::common::{
     AtomicOrdering, AtomicRmwBinOp, IntPredicate, RealPredicate, SynchronizationScope, TypeKind,
 };
@@ -33,17 +33,33 @@ pub enum OverflowOp {
 }
 
 pub trait BuilderMethods<'a, 'tcx>:
-    HasCodegen<'tcx>
+    Sized
+    + LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
+    + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
+    + Deref<Target = Self::CodegenCx>
     + CoverageInfoBuilderMethods<'tcx>
     + DebugInfoBuilderMethods
-    + ArgAbiMethods<'tcx>
+    + ArgAbiBuilderMethods<'tcx>
     + AbiBuilderMethods<'tcx>
-    + IntrinsicCallMethods<'tcx>
+    + IntrinsicCallBuilderMethods<'tcx>
     + AsmBuilderMethods<'tcx>
     + StaticBuilderMethods
-    + HasParamEnv<'tcx>
-    + HasTargetSpec
 {
+    // `BackendTypes` is a supertrait of both `CodegenMethods` and
+    // `BuilderMethods`. This bound ensures all impls agree on the associated
+    // types within.
+    type CodegenCx: CodegenMethods<
+            'tcx,
+            Value = Self::Value,
+            Function = Self::Function,
+            BasicBlock = Self::BasicBlock,
+            Type = Self::Type,
+            Funclet = Self::Funclet,
+            DIScope = Self::DIScope,
+            DILocation = Self::DILocation,
+            DIVariable = Self::DIVariable,
+        >;
+
     fn build(cx: &'a Self::CodegenCx, llbb: Self::BasicBlock) -> Self;
 
     fn cx(&self) -> &Self::CodegenCx;

compiler/rustc_codegen_ssa/src/traits/consts.rs

@@ -3,7 +3,7 @@ use rustc_target::abi;
 
 use super::BackendTypes;
 
-pub trait ConstMethods<'tcx>: BackendTypes {
+pub trait ConstCodegenMethods<'tcx>: BackendTypes {
     // Constant constructors
     fn const_null(&self, t: Self::Type) -> Self::Value;
     /// Generate an uninitialized value (matching uninitialized memory in MIR).

compiler/rustc_codegen_ssa/src/traits/coverageinfo.rs

@@ -1,9 +1,7 @@
 use rustc_middle::mir::coverage::CoverageKind;
 use rustc_middle::ty::Instance;
 
-use super::BackendTypes;
-
-pub trait CoverageInfoBuilderMethods<'tcx>: BackendTypes {
+pub trait CoverageInfoBuilderMethods<'tcx> {
     /// Performs any start-of-function codegen needed for coverage instrumentation.
     ///
     /// Can be a no-op in backends that don't support coverage instrumentation.

compiler/rustc_codegen_ssa/src/traits/debuginfo.rs

@@ -9,7 +9,7 @@ use rustc_target::abi::Size;
 use super::BackendTypes;
 use crate::mir::debuginfo::{FunctionDebugContext, VariableKind};
 
-pub trait DebugInfoMethods<'tcx>: BackendTypes {
+pub trait DebugInfoCodegenMethods<'tcx>: BackendTypes {
     fn create_vtable_debuginfo(
         &self,
         ty: Ty<'tcx>,

compiler/rustc_codegen_ssa/src/traits/declare.rs

@@ -2,9 +2,7 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::mir::mono::{Linkage, Visibility};
 use rustc_middle::ty::Instance;
 
-use super::BackendTypes;
-
-pub trait PreDefineMethods<'tcx>: BackendTypes {
+pub trait PreDefineCodegenMethods<'tcx> {
     fn predefine_static(
         &self,
         def_id: DefId,

compiler/rustc_codegen_ssa/src/traits/intrinsic.rs

@@ -5,7 +5,7 @@ use rustc_target::abi::call::FnAbi;
 use super::BackendTypes;
 use crate::mir::operand::OperandRef;
 
-pub trait IntrinsicCallMethods<'tcx>: BackendTypes {
+pub trait IntrinsicCallBuilderMethods<'tcx>: BackendTypes {
     /// Remember to add all intrinsics here, in `compiler/rustc_hir_analysis/src/check/mod.rs`,
     /// and in `library/core/src/intrinsics.rs`; if you need access to any LLVM intrinsics,
     /// add them to `compiler/rustc_codegen_llvm/src/context.rs`.

compiler/rustc_codegen_ssa/src/traits/misc.rs

@@ -7,7 +7,7 @@ use rustc_session::Session;
 
 use super::BackendTypes;
 
-pub trait MiscMethods<'tcx>: BackendTypes {
+pub trait MiscCodegenMethods<'tcx>: BackendTypes {
     fn vtables(
         &self,
     ) -> &RefCell<FxHashMap<(Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>), Self::Value>>;

compiler/rustc_codegen_ssa/src/traits/mod.rs

@@ -8,9 +8,6 @@
 //! actual codegen, while the builder stores the information about the function during codegen and
 //! is used to produce the instructions of the backend IR.
 //!
-//! Finally, a third `Backend` structure has to implement methods related to how codegen information
-//! is passed to the backend, especially for asynchronous compilation.
-//!
 //! The traits contain associated types that are backend-specific, such as the backend's value or
 //! basic blocks.
 
@@ -30,71 +27,36 @@ mod write;
 
 use std::fmt;
 
-use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt};
-use rustc_target::spec::HasTargetSpec;
+use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
+use rustc_middle::ty::Ty;
+use rustc_target::abi::call::FnAbi;
 
 pub use self::abi::AbiBuilderMethods;
-pub use self::asm::{AsmBuilderMethods, AsmMethods, GlobalAsmOperandRef, InlineAsmOperandRef};
-pub use self::backend::{Backend, BackendTypes, CodegenBackend, ExtraBackendMethods};
+pub use self::asm::{
+    AsmBuilderMethods, AsmCodegenMethods, GlobalAsmOperandRef, InlineAsmOperandRef,
+};
+pub use self::backend::{BackendTypes, CodegenBackend, ExtraBackendMethods};
 pub use self::builder::{BuilderMethods, OverflowOp};
-pub use self::consts::ConstMethods;
+pub use self::consts::ConstCodegenMethods;
 pub use self::coverageinfo::CoverageInfoBuilderMethods;
-pub use self::debuginfo::{DebugInfoBuilderMethods, DebugInfoMethods};
-pub use self::declare::PreDefineMethods;
-pub use self::intrinsic::IntrinsicCallMethods;
-pub use self::misc::MiscMethods;
-pub use self::statics::{StaticBuilderMethods, StaticMethods};
+pub use self::debuginfo::{DebugInfoBuilderMethods, DebugInfoCodegenMethods};
+pub use self::declare::PreDefineCodegenMethods;
+pub use self::intrinsic::IntrinsicCallBuilderMethods;
+pub use self::misc::MiscCodegenMethods;
+pub use self::statics::{StaticBuilderMethods, StaticCodegenMethods};
 pub use self::type_::{
-    ArgAbiMethods, BaseTypeMethods, DerivedTypeMethods, LayoutTypeMethods, TypeMembershipMethods,
-    TypeMethods,
+    ArgAbiBuilderMethods, BaseTypeCodegenMethods, DerivedTypeCodegenMethods,
+    LayoutTypeCodegenMethods, TypeCodegenMethods, TypeMembershipCodegenMethods,
 };
 pub use self::write::{ModuleBufferMethods, ThinBufferMethods, WriteBackendMethods};
 
-pub trait CodegenObject: Copy + PartialEq + fmt::Debug {}
-impl<T: Copy + PartialEq + fmt::Debug> CodegenObject for T {}
+pub trait CodegenObject = Copy + PartialEq + fmt::Debug;
 
-pub trait CodegenMethods<'tcx>:
-    Backend<'tcx>
-    + TypeMethods<'tcx>
-    + MiscMethods<'tcx>
-    + ConstMethods<'tcx>
-    + StaticMethods
-    + DebugInfoMethods<'tcx>
-    + AsmMethods<'tcx>
-    + PreDefineMethods<'tcx>
-    + HasParamEnv<'tcx>
-    + HasTyCtxt<'tcx>
-    + HasTargetSpec
-{
-}
-
-impl<'tcx, T> CodegenMethods<'tcx> for T where
-    Self: Backend<'tcx>
-        + TypeMethods<'tcx>
-        + MiscMethods<'tcx>
-        + ConstMethods<'tcx>
-        + StaticMethods
-        + DebugInfoMethods<'tcx>
-        + AsmMethods<'tcx>
-        + PreDefineMethods<'tcx>
-        + HasParamEnv<'tcx>
-        + HasTyCtxt<'tcx>
-        + HasTargetSpec
-{
-}
-
-pub trait HasCodegen<'tcx>:
-    Backend<'tcx> + std::ops::Deref<Target = <Self as HasCodegen<'tcx>>::CodegenCx>
-{
-    type CodegenCx: CodegenMethods<'tcx>
-        + BackendTypes<
-            Value = Self::Value,
-            Function = Self::Function,
-            BasicBlock = Self::BasicBlock,
-            Type = Self::Type,
-            Funclet = Self::Funclet,
-            DIScope = Self::DIScope,
-            DILocation = Self::DILocation,
-            DIVariable = Self::DIVariable,
-        >;
-}
+pub trait CodegenMethods<'tcx> = LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
+    + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
+    + TypeCodegenMethods<'tcx>
+    + ConstCodegenMethods<'tcx>
+    + StaticCodegenMethods
+    + DebugInfoCodegenMethods<'tcx>
+    + AsmCodegenMethods<'tcx>
+    + PreDefineCodegenMethods<'tcx>;

compiler/rustc_codegen_ssa/src/traits/statics.rs

@@ -3,7 +3,7 @@ use rustc_target::abi::Align;
 
 use super::BackendTypes;
 
-pub trait StaticMethods: 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);
 

compiler/rustc_codegen_ssa/src/traits/type_.rs

@@ -1,17 +1,15 @@
 use rustc_middle::bug;
-use rustc_middle::ty::layout::TyAndLayout;
+use rustc_middle::ty::layout::{HasTyCtxt, TyAndLayout};
 use rustc_middle::ty::{self, Ty};
 use rustc_target::abi::call::{ArgAbi, CastTarget, FnAbi, Reg};
 use rustc_target::abi::{AddressSpace, Float, Integer};
 
-use super::misc::MiscMethods;
-use super::{Backend, HasCodegen};
+use super::misc::MiscCodegenMethods;
+use super::BackendTypes;
 use crate::common::TypeKind;
 use crate::mir::place::PlaceRef;
 
-// This depends on `Backend` and not `BackendTypes`, because consumers will probably want to use
-// `LayoutOf` or `HasTyCtxt`. This way, they don't have to add a constraint on it themselves.
-pub trait BaseTypeMethods<'tcx>: Backend<'tcx> {
+pub trait BaseTypeCodegenMethods<'tcx>: BackendTypes {
     fn type_i8(&self) -> Self::Type;
     fn type_i16(&self) -> Self::Type;
     fn type_i32(&self) -> Self::Type;
@@ -42,7 +40,9 @@ pub trait BaseTypeMethods<'tcx>: Backend<'tcx> {
     fn val_ty(&self, v: Self::Value) -> Self::Type;
 }
 
-pub trait DerivedTypeMethods<'tcx>: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {
+pub trait DerivedTypeCodegenMethods<'tcx>:
+    BaseTypeCodegenMethods<'tcx> + MiscCodegenMethods<'tcx> + HasTyCtxt<'tcx>
+{
     fn type_int(&self) -> Self::Type {
         match &self.sess().target.c_int_width[..] {
             "16" => self.type_i16(),
@@ -100,9 +100,12 @@ pub trait DerivedTypeMethods<'tcx>: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {
     }
 }
 
-impl<'tcx, T> DerivedTypeMethods<'tcx> for T where Self: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {}
+impl<'tcx, T> DerivedTypeCodegenMethods<'tcx> for T where
+    Self: BaseTypeCodegenMethods<'tcx> + MiscCodegenMethods<'tcx> + HasTyCtxt<'tcx>
+{
+}
 
-pub trait LayoutTypeMethods<'tcx>: Backend<'tcx> {
+pub trait LayoutTypeCodegenMethods<'tcx>: BackendTypes {
     /// The backend type used for a rust type when it's in memory,
     /// such as when it's stack-allocated or when it's being loaded or stored.
     fn backend_type(&self, layout: TyAndLayout<'tcx>) -> Self::Type;
@@ -114,7 +117,7 @@ pub trait LayoutTypeMethods<'tcx>: Backend<'tcx> {
     ///
     /// For nearly all types this is the same as the [`Self::backend_type`], however
     /// `bool` (and other `0`-or-`1` values) are kept as `i1` in registers but as
-    /// [`BaseTypeMethods::type_i8`] in memory.
+    /// [`BaseTypeCodegenMethods::type_i8`] in memory.
     ///
     /// Converting values between the two different backend types is done using
     /// [`from_immediate`](super::BuilderMethods::from_immediate) and
@@ -146,7 +149,7 @@ pub trait LayoutTypeMethods<'tcx>: Backend<'tcx> {
 
 // For backends that support CFI using type membership (i.e., testing whether a given pointer is
 // associated with a type identifier).
-pub trait TypeMembershipMethods<'tcx>: Backend<'tcx> {
+pub trait TypeMembershipCodegenMethods<'tcx>: BackendTypes {
     fn add_type_metadata(&self, _function: Self::Function, _typeid: String) {}
     fn set_type_metadata(&self, _function: Self::Function, _typeid: String) {}
     fn typeid_metadata(&self, _typeid: String) -> Option<Self::Value> {
@@ -156,7 +159,7 @@ pub trait TypeMembershipMethods<'tcx>: Backend<'tcx> {
     fn set_kcfi_type_metadata(&self, _function: Self::Function, _typeid: u32) {}
 }
 
-pub trait ArgAbiMethods<'tcx>: HasCodegen<'tcx> {
+pub trait ArgAbiBuilderMethods<'tcx>: BackendTypes {
     fn store_fn_arg(
         &mut self,
         arg_abi: &ArgAbi<'tcx, Ty<'tcx>>,
@@ -172,12 +175,6 @@ pub trait ArgAbiMethods<'tcx>: HasCodegen<'tcx> {
     fn arg_memory_ty(&self, arg_abi: &ArgAbi<'tcx, Ty<'tcx>>) -> Self::Type;
 }
 
-pub trait TypeMethods<'tcx>:
-    DerivedTypeMethods<'tcx> + LayoutTypeMethods<'tcx> + TypeMembershipMethods<'tcx>
-{
-}
-
-impl<'tcx, T> TypeMethods<'tcx> for T where
-    Self: DerivedTypeMethods<'tcx> + LayoutTypeMethods<'tcx> + TypeMembershipMethods<'tcx>
-{
-}
+pub trait TypeCodegenMethods<'tcx> = DerivedTypeCodegenMethods<'tcx>
+    + LayoutTypeCodegenMethods<'tcx>
+    + TypeMembershipCodegenMethods<'tcx>;

compiler/rustc_middle/src/lib.rs

@@ -33,6 +33,7 @@
 #![feature(allocator_api)]
 #![feature(array_windows)]
 #![feature(assert_matches)]
+#![feature(associated_type_defaults)]
 #![feature(box_as_ptr)]
 #![feature(box_patterns)]
 #![feature(closure_track_caller)]

compiler/rustc_middle/src/ty/layout.rs

@@ -627,7 +627,7 @@ pub type TyAndLayout<'tcx> = rustc_target::abi::TyAndLayout<'tcx, Ty<'tcx>>;
 pub trait LayoutOfHelpers<'tcx>: HasDataLayout + HasTyCtxt<'tcx> + HasParamEnv<'tcx> {
     /// The `TyAndLayout`-wrapping type (or `TyAndLayout` itself), which will be
     /// returned from `layout_of` (see also `handle_layout_err`).
-    type LayoutOfResult: MaybeResult<TyAndLayout<'tcx>>;
+    type LayoutOfResult: MaybeResult<TyAndLayout<'tcx>> = TyAndLayout<'tcx>;
 
     /// `Span` to use for `tcx.at(span)`, from `layout_of`.
     // FIXME(eddyb) perhaps make this mandatory to get contexts to track it better?
@@ -1233,7 +1233,7 @@ pub enum FnAbiRequest<'tcx> {
 pub trait FnAbiOfHelpers<'tcx>: LayoutOfHelpers<'tcx> {
     /// The `&FnAbi`-wrapping type (or `&FnAbi` itself), which will be
     /// returned from `fn_abi_of_*` (see also `handle_fn_abi_err`).
-    type FnAbiOfResult: MaybeResult<&'tcx FnAbi<'tcx, Ty<'tcx>>>;
+    type FnAbiOfResult: MaybeResult<&'tcx FnAbi<'tcx, Ty<'tcx>>> = &'tcx FnAbi<'tcx, Ty<'tcx>>;
 
     /// Helper used for `fn_abi_of_*`, to adapt `tcx.fn_abi_of_*(...)` into a
     /// `Self::FnAbiOfResult` (which does not need to be a `Result<...>`).

compiler/rustc_passes/src/layout_test.rs

@@ -2,7 +2,7 @@ use rustc_ast::Attribute;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LocalDefId;
 use rustc_middle::span_bug;
-use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers, TyAndLayout};
+use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers};
 use rustc_middle::ty::{self, ParamEnv, Ty, TyCtxt};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::sym;
@@ -139,8 +139,6 @@ struct UnwrapLayoutCx<'tcx> {
 }
 
 impl<'tcx> LayoutOfHelpers<'tcx> for UnwrapLayoutCx<'tcx> {
-    type LayoutOfResult = TyAndLayout<'tcx>;
-
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         span_bug!(span, "`#[rustc_layout(..)]` test resulted in `layout_of({ty}) = Err({err})`",);
     }