Use derives on CanonAbi

Author: workingjubilee

compiler/rustc_abi/src/canon_abi.rs

@@ -1,9 +1,7 @@
-use std::cmp::{Eq, Ord, Ordering, PartialEq, PartialOrd};
 use std::fmt;
-use std::hash::{Hash, Hasher};
 
 #[cfg(feature = "nightly")]
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher, StableOrd};
+use rustc_macros::HashStable_Generic;
 
 use crate::ExternAbi;
 
@@ -19,6 +17,8 @@ use crate::ExternAbi;
 /// In that sense, this erases mere syntactic distinctions to create a canonical *directive*,
 /// rather than picking the "actual" ABI.
 #[derive(Copy, Clone, Debug)]
+#[derive(PartialOrd, Ord, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "nightly", derive(HashStable_Generic))]
 pub enum CanonAbi {
     // NOTE: the use of nested variants for some ABIs is for many targets they don't matter,
     // and this pushes the complexity of their reasoning to target-specific code,
@@ -48,50 +48,6 @@ pub enum CanonAbi {
     X86(X86Call),
 }
 
-// For most "utility" impls, just forward CanonAbi to ExternAbi as it is notionally a subset
-impl Ord for CanonAbi {
-    fn cmp(&self, other: &Self) -> Ordering {
-        self.to_erased_extern_abi().cmp(&other.to_erased_extern_abi())
-    }
-}
-
-impl PartialOrd for CanonAbi {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        Some(self.cmp(&other))
-    }
-}
-
-impl PartialEq for CanonAbi {
-    fn eq(&self, other: &Self) -> bool {
-        self.cmp(&other) == Ordering::Equal
-    }
-}
-
-impl Eq for CanonAbi {}
-
-impl Hash for CanonAbi {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        self.to_erased_extern_abi().hash(state)
-    }
-}
-
-// because we forward hashing to ExternAbi, also forward this:
-#[cfg(feature = "nightly")]
-impl<C> HashStable<C> for CanonAbi {
-    #[inline]
-    fn hash_stable(&self, _: &mut C, hasher: &mut StableHasher) {
-        Hash::hash(self, hasher);
-    }
-}
-
-#[cfg(feature = "nightly")]
-impl StableOrd for CanonAbi {
-    const CAN_USE_UNSTABLE_SORT: bool = true;
-
-    // because each ABI is hashed like a string, there is no possible instability
-    const THIS_IMPLEMENTATION_HAS_BEEN_TRIPLE_CHECKED: () = ();
-}
-
 impl fmt::Display for CanonAbi {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         self.to_erased_extern_abi().fmt(f)
@@ -141,6 +97,8 @@ impl CanonAbi {
 /// these "ABI" differences are not relevant to callers, since there is "no caller".
 /// These only affect callee codegen. making their categorization as distinct ABIs a bit peculiar.
 #[derive(Copy, Clone, Debug)]
+#[derive(PartialOrd, Ord, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "nightly", derive(HashStable_Generic))]
 pub enum InterruptKind {
     Avr,
     AvrNonBlocking,
@@ -154,6 +112,8 @@ pub enum InterruptKind {
 ///
 /// One of SysV64 or Win64 may alias the C ABI, and arguably Win64 is cross-platform now?
 #[derive(Clone, Copy, Debug)]
+#[derive(PartialOrd, Ord, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "nightly", derive(HashStable_Generic))]
 pub enum X86Call {
     /// "fastcall" has both GNU and Windows variants
     Fastcall,
@@ -167,6 +127,8 @@ pub enum X86Call {
 
 /// ABIs defined for 32-bit Arm
 #[derive(Copy, Clone, Debug)]
+#[derive(PartialOrd, Ord, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "nightly", derive(HashStable_Generic))]
 pub enum ArmCall {
     Aapcs,
     CCmseNonSecureCall,