Make FnAbiError Copy.

compiler/rustc_codegen_cranelift/src/common.rs

@@ -274,7 +274,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> {
     #[inline]
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {
@@ -396,7 +396,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
     #[inline]
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {

compiler/rustc_codegen_gcc/src/builder.rs

@@ -354,7 +354,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
     #[inline]
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {

compiler/rustc_codegen_gcc/src/context.rs

@@ -397,7 +397,7 @@ impl<'gcc, 'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
     #[inline]
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {

compiler/rustc_codegen_llvm/src/builder.rs

@@ -105,7 +105,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for Builder<'_, '_, 'tcx> {
     #[inline]
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {

compiler/rustc_codegen_llvm/src/context.rs

@@ -920,7 +920,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
     #[inline]
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -341,12 +341,12 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> FnAbiOfHelpers<'tcx> for InterpCx
 
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         _span: Span,
         _fn_abi_request: FnAbiRequest<'tcx>,
     ) -> InterpErrorInfo<'tcx> {
         match err {
-            FnAbiError::Layout(err) => err_inval!(Layout(*err)).into(),
+            FnAbiError::Layout(err) => err_inval!(Layout(err)).into(),
             FnAbiError::AdjustForForeignAbi(err) => {
                 err_inval!(FnAbiAdjustForForeignAbi(err)).into()
             }

compiler/rustc_middle/src/mir/interpret/error.rs

@@ -144,7 +144,7 @@ pub enum InvalidProgramInfo<'tcx> {
     /// An error occurred during FnAbi computation: the passed --target lacks FFI support
     /// (which unfortunately typeck does not reject).
     /// Not using `FnAbiError` as that contains a nested `LayoutError`.
-    FnAbiAdjustForForeignAbi(&'tcx call::AdjustForForeignAbiError),
+    FnAbiAdjustForForeignAbi(call::AdjustForForeignAbiError),
     /// An invalid transmute happened.
     TransmuteSizeDiff(Ty<'tcx>, Ty<'tcx>),
     /// SizeOf of unsized type was requested.

compiler/rustc_middle/src/query/mod.rs

@@ -1217,8 +1217,7 @@ rustc_queries! {
     /// instead, where the instance is an `InstanceDef::Virtual`.
     query fn_abi_of_fn_ptr(
         key: ty::ParamEnvAnd<'tcx, (ty::PolyFnSig<'tcx>, &'tcx ty::List<Ty<'tcx>>)>
-    ) -> Result<abi::call::FnAbi<'tcx, Ty<'tcx>>, ty::layout::FnAbiError<'tcx>> {
+    ) -> Result<&'tcx abi::call::FnAbi<'tcx, Ty<'tcx>>, ty::layout::FnAbiError<'tcx>> {
-        storage(ArenaCacheSelector<'tcx>)
         desc { "computing call ABI of `{}` function pointers", key.value.0 }
         remap_env_constness
     }
@@ -1230,8 +1229,7 @@ rustc_queries! {
     /// to an `InstanceDef::Virtual` instance (of `<dyn Trait as Trait>::fn`).
     query fn_abi_of_instance(
         key: ty::ParamEnvAnd<'tcx, (ty::Instance<'tcx>, &'tcx ty::List<Ty<'tcx>>)>
-    ) -> Result<abi::call::FnAbi<'tcx, Ty<'tcx>>, ty::layout::FnAbiError<'tcx>> {
+    ) -> Result<&'tcx abi::call::FnAbi<'tcx, Ty<'tcx>>, ty::layout::FnAbiError<'tcx>> {
-        storage(ArenaCacheSelector<'tcx>)
         desc { "computing call ABI of `{}`", key.value.0 }
         remap_env_constness
     }

compiler/rustc_middle/src/ty/layout.rs

@@ -2839,7 +2839,7 @@ pub fn conv_from_spec_abi(tcx: TyCtxt<'_>, abi: SpecAbi) -> Conv {
 }
 
 /// Error produced by attempting to compute or adjust a `FnAbi`.
-#[derive(Clone, Debug, HashStable)]
+#[derive(Copy, Clone, Debug, HashStable)]
 pub enum FnAbiError<'tcx> {
     /// Error produced by a `layout_of` call, while computing `FnAbi` initially.
     Layout(LayoutError<'tcx>),
@@ -2893,7 +2893,7 @@ pub trait FnAbiOfHelpers<'tcx>: LayoutOfHelpers<'tcx> {
     /// (and any `FnAbiError`s are turned into fatal errors or ICEs).
     fn handle_fn_abi_err(
         &self,
-        err: &'tcx FnAbiError<'tcx>,
+        err: FnAbiError<'tcx>,
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> <Self::FnAbiOfResult as MaybeResult<&'tcx FnAbi<'tcx, Ty<'tcx>>>>::Error;
@@ -2915,11 +2915,9 @@ pub trait FnAbiOf<'tcx>: FnAbiOfHelpers<'tcx> {
         let span = self.layout_tcx_at_span();
         let tcx = self.tcx().at(span);
 
-        MaybeResult::from(
+        MaybeResult::from(tcx.fn_abi_of_fn_ptr(self.param_env().and((sig, extra_args))).map_err(
-            tcx.fn_abi_of_fn_ptr(self.param_env().and((sig, extra_args))).as_ref().map_err(|err| {
+            |err| self.handle_fn_abi_err(err, span, FnAbiRequest::OfFnPtr { sig, extra_args }),
-                self.handle_fn_abi_err(err, span, FnAbiRequest::OfFnPtr { sig, extra_args })
+        ))
-            }),
-        )
     }
 
     /// Compute a `FnAbi` suitable for declaring/defining an `fn` instance, and for
@@ -2938,21 +2936,14 @@ pub trait FnAbiOf<'tcx>: FnAbiOfHelpers<'tcx> {
         let tcx = self.tcx().at(span);
 
         MaybeResult::from(
-            tcx.fn_abi_of_instance(self.param_env().and((instance, extra_args))).as_ref().map_err(
+            tcx.fn_abi_of_instance(self.param_env().and((instance, extra_args))).map_err(|err| {
-                |err| {
+                // HACK(eddyb) at least for definitions of/calls to `Instance`s,
-                    // HACK(eddyb) at least for definitions of/calls to `Instance`s,
+                // we can get some kind of span even if one wasn't provided.
-                    // we can get some kind of span even if one wasn't provided.
+                // However, we don't do this early in order to avoid calling
-                    // However, we don't do this early in order to avoid calling
+                // `def_span` unconditionally (which may have a perf penalty).
-                    // `def_span` unconditionally (which may have a perf penalty).
+                let span = if !span.is_dummy() { span } else { tcx.def_span(instance.def_id()) };
-                    let span =
+                self.handle_fn_abi_err(err, span, FnAbiRequest::OfInstance { instance, extra_args })
-                        if !span.is_dummy() { span } else { tcx.def_span(instance.def_id()) };
+            }),
-                    self.handle_fn_abi_err(
-                        err,
-                        span,
-                        FnAbiRequest::OfInstance { instance, extra_args },
-                    )
-                },
-            ),
         )
     }
 }
@@ -2962,7 +2953,7 @@ impl<'tcx, C: FnAbiOfHelpers<'tcx>> FnAbiOf<'tcx> for C {}
 fn fn_abi_of_fn_ptr<'tcx>(
     tcx: TyCtxt<'tcx>,
     query: ty::ParamEnvAnd<'tcx, (ty::PolyFnSig<'tcx>, &'tcx ty::List<Ty<'tcx>>)>,
-) -> Result<FnAbi<'tcx, Ty<'tcx>>, FnAbiError<'tcx>> {
+) -> Result<&'tcx FnAbi<'tcx, Ty<'tcx>>, FnAbiError<'tcx>> {
     let (param_env, (sig, extra_args)) = query.into_parts();
 
     LayoutCx { tcx, param_env }.fn_abi_new_uncached(
@@ -2977,7 +2968,7 @@ fn fn_abi_of_fn_ptr<'tcx>(
 fn fn_abi_of_instance<'tcx>(
     tcx: TyCtxt<'tcx>,
     query: ty::ParamEnvAnd<'tcx, (ty::Instance<'tcx>, &'tcx ty::List<Ty<'tcx>>)>,
-) -> Result<FnAbi<'tcx, Ty<'tcx>>, FnAbiError<'tcx>> {
+) -> Result<&'tcx FnAbi<'tcx, Ty<'tcx>>, FnAbiError<'tcx>> {
     let (param_env, (instance, extra_args)) = query.into_parts();
 
     let sig = instance.fn_sig_for_fn_abi(tcx, param_env);
@@ -3010,7 +3001,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
         codegen_fn_attr_flags: CodegenFnAttrFlags,
         // FIXME(eddyb) replace this with something typed, like an `enum`.
         force_thin_self_ptr: bool,
-    ) -> Result<FnAbi<'tcx, Ty<'tcx>>, FnAbiError<'tcx>> {
+    ) -> Result<&'tcx FnAbi<'tcx, Ty<'tcx>>, FnAbiError<'tcx>> {
         debug!("fn_abi_new_uncached({:?}, {:?})", sig, extra_args);
 
         let sig = self.tcx.normalize_erasing_late_bound_regions(self.param_env, sig);
@@ -3174,7 +3165,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
         };
         self.fn_abi_adjust_for_abi(&mut fn_abi, sig.abi)?;
         debug!("fn_abi_new_uncached = {:?}", fn_abi);
-        Ok(fn_abi)
+        Ok(self.tcx.arena.alloc(fn_abi))
     }
 
     fn fn_abi_adjust_for_abi(

compiler/rustc_target/src/abi/call/mod.rs

@@ -1,6 +1,7 @@
 use crate::abi::{self, Abi, Align, FieldsShape, Size};
 use crate::abi::{HasDataLayout, TyAbiInterface, TyAndLayout};
 use crate::spec::{self, HasTargetSpec};
+use rustc_span::Symbol;
 use std::fmt;
 
 mod aarch64;
@@ -623,10 +624,10 @@ pub struct FnAbi<'a, Ty> {
 }
 
 /// Error produced by attempting to adjust a `FnAbi`, for a "foreign" ABI.
-#[derive(Clone, Debug, HashStable_Generic)]
+#[derive(Copy, Clone, Debug, HashStable_Generic)]
 pub enum AdjustForForeignAbiError {
     /// Target architecture doesn't support "foreign" (i.e. non-Rust) ABIs.
-    Unsupported { arch: String, abi: spec::abi::Abi },
+    Unsupported { arch: Symbol, abi: spec::abi::Abi },
 }
 
 impl fmt::Display for AdjustForForeignAbiError {
@@ -703,7 +704,10 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             "asmjs" => wasm::compute_c_abi_info(cx, self),
             "bpf" => bpf::compute_abi_info(self),
             arch => {
-                return Err(AdjustForForeignAbiError::Unsupported { arch: arch.to_string(), abi });
+                return Err(AdjustForForeignAbiError::Unsupported {
+                    arch: Symbol::intern(arch),
+                    abi,
+                });
             }
         }