[region-isolation] Re-group diagnostics in header based on which diagnostic emitter they are used by.

It just makes it easier to reason about which diagnostics one is changing as one
is working on them.

This is NFC.

Author: gottesmm

include/swift/AST/DiagnosticsSIL.def

@@ -935,55 +935,39 @@ NOTE(sil_referencebinding_inout_binding_here, none,
 //                  MARK: Region Based Isolation Diagnostics
 //===----------------------------------------------------------------------===//
 
-NOTE(regionbasedisolation_maybe_race, none,
-     "access can happen concurrently", ())
-NOTE(regionbasedisolation_inout_sending_must_be_reinitialized, none,
-     "'inout sending' parameter must be reinitialized before function exit with a non-actor isolated value",
-     ())
+// READ THIS: Please when adding diagnostics for region based isolation, keep
+// them ordered in sections depending on which emitter uses it. It makes it
+// easier for people unfamiliar with the code to quickly see which diagnostics
+// are used by which of the SendNonSendable emitters use.
+
+//===
+// Misc
+
 ERROR(regionbasedisolation_unknown_pattern, none,
       "pattern that the region based isolation checker does not understand how to check. Please file a bug",
       ())
+NOTE(regionbasedisolation_maybe_race, none,
+     "access can happen concurrently", ())
+NOTE(regionbasedisolation_type_is_non_sendable, none,
+      "%0 is a non-Sendable type",
+      (Type))
+
+//===
+// Use After Send Emitter
 
 ERROR(regionbasedisolation_named_transfer_yields_race, none,
       "sending %0 risks causing data races",
       (Identifier))
-NOTE(regionbasedisolation_type_is_non_sendable, none,
-      "%0 is a non-Sendable type",
-      (Type))
 ERROR(regionbasedisolation_type_transfer_yields_race, none,
       "sending value of non-Sendable type %0 risks causing data races",
       (Type))
-
 NOTE(regionbasedisolation_type_use_after_transfer, none,
       "sending value of non-Sendable type %0 to %1 callee risks causing data races between %1 and local %2 uses",
       (Type, ActorIsolation, ActorIsolation))
 NOTE(regionbasedisolation_type_use_after_transfer_callee, none,
-      "sending value of non-Sendable type %0 to %1 %2 %3 risks causing data races between %1 and local %4 uses",
-      (Type, ActorIsolation, DescriptiveDeclKind, DeclName, ActorIsolation))
-NOTE(regionbasedisolation_type_isolated_capture_yields_race, none,
-      "sending value of non-Sendable type %0 to %1 closure due to closure capture risks causing races in between %1 and %2 uses",
-      (Type, ActorIsolation, ActorIsolation))
-
-ERROR(regionbasedisolation_inout_sending_cannot_be_actor_isolated, none,
-      "'inout sending' parameter %0 cannot be %1at end of function",
-      (Identifier, StringRef))
-NOTE(regionbasedisolation_inout_sending_cannot_be_actor_isolated_note, none,
-      "%1%0 risks causing races in between %1uses and caller uses since caller assumes value is not actor isolated",
-      (Identifier, StringRef))
-
-ERROR(regionbasedisolation_out_sending_cannot_be_actor_isolated_type, none,
-      "returning a %1 %0 value as a 'sending' result risks causing data races",
-      (Type, StringRef))
-NOTE(regionbasedisolation_out_sending_cannot_be_actor_isolated_note_type, none,
-      "returning a %1 %0 value risks causing races since the caller assumes the value can be safely sent to other isolation domains",
-      (Type, StringRef))
-
-ERROR(regionbasedisolation_out_sending_cannot_be_actor_isolated_named, none,
-      "returning %1 %0 as a 'sending' result risks causing data races",
-      (Identifier, StringRef))
-NOTE(regionbasedisolation_out_sending_cannot_be_actor_isolated_note_named, none,
-      "returning %1 %0 risks causing data races since the caller assumes that %0 can be safely sent to other isolation domains",
-      (Identifier, StringRef))
+     "sending value of non-Sendable type %0 to %1 %2 %3 risks causing data "
+     "races between %1 and local %4 uses",
+     (Type, ActorIsolation, DescriptiveDeclKind, DeclName, ActorIsolation))
 
 NOTE(regionbasedisolation_named_info_transfer_yields_race, none,
      "sending %1%0 to %2 callee risks causing data races between %2 and local %3 uses",
@@ -992,57 +976,104 @@ NOTE(regionbasedisolation_named_info_transfer_yields_race_callee, none,
      "sending %1%0 to %2 %3 %4 risks causing data races between %2 and local %5 uses",
      (Identifier, StringRef, ActorIsolation, DescriptiveDeclKind, DeclName, ActorIsolation))
 
+// Use after transfer closure.
+NOTE(regionbasedisolation_type_isolated_capture_yields_race, none,
+      "sending value of non-Sendable type %0 to %1 closure due to closure capture risks causing races in between %1 and %2 uses",
+      (Type, ActorIsolation, ActorIsolation))
+
+// Value captured in async let and reused.
+NOTE(regionbasedisolation_named_nonisolated_asynclet_name, none,
+      "sending %0 into async let risks causing data races between async let uses and local uses",
+      (Identifier))
+
+NOTE(regionbasedisolation_named_value_used_after_explicit_sending, none,
+      "%0 used after being passed as a 'sending' parameter; Later uses could race",
+      (Identifier))
+NOTE(regionbasedisolation_named_isolated_closure_yields_race, none,
+      "%0%1 is captured by a %2 closure. %2 uses in closure may race against later %3 uses",
+      (StringRef, Identifier, ActorIsolation, ActorIsolation))
+
+NOTE(regionbasedisolation_typed_use_after_sending, none,
+      "Passing value of non-Sendable type %0 as a 'sending' argument risks causing races in between local and caller code",
+      (Type))
+NOTE(regionbasedisolation_typed_use_after_sending_callee, none,
+      "Passing value of non-Sendable type %0 as a 'sending' argument to %1 %2 risks causing races in between local and caller code",
+      (Type, DescriptiveDeclKind, DeclName))
+
+//===
+// Sending Never Sendable Emitter
+
 NOTE(regionbasedisolation_named_transfer_non_transferrable, none,
       "sending %1%0 to %2 callee risks causing data races between %2 and %3 uses",
       (Identifier, StringRef, ActorIsolation, StringRef))
 NOTE(regionbasedisolation_named_transfer_non_transferrable_callee, none,
       "sending %1%0 to %2 %3 %4 risks causing data races between %2 and %5 uses",
       (Identifier, StringRef, ActorIsolation, DescriptiveDeclKind, DeclName, StringRef))
-NOTE(regionbasedisolation_named_nonisolated_asynclet_name, none,
-      "sending %0 into async let risks causing data races between async let uses and local uses",
-      (Identifier))
 
 NOTE(regionbasedisolation_named_transfer_into_sending_param, none,
-     "%0%1 is passed as a 'sending' parameter; Uses in callee may race with later %0uses",
+     "%0%1 is passed as a 'sending' parameter; Uses in callee may race with "
+     "later %0uses",
      (StringRef, Identifier))
 NOTE(regionbasedisolation_named_notransfer_transfer_into_result, none,
      "%0%1 cannot be a 'sending' result. %2 uses may race with caller uses",
      (StringRef, Identifier, StringRef))
-NOTE(regionbasedisolation_named_value_used_after_explicit_sending, none,
-      "%0 used after being passed as a 'sending' parameter; Later uses could race",
-      (Identifier))
-NOTE(regionbasedisolation_named_isolated_closure_yields_race, none,
-      "%0%1 is captured by a %2 closure. %2 uses in closure may race against later %3 uses",
-      (StringRef, Identifier, ActorIsolation, ActorIsolation))
 NOTE(regionbasedisolation_typed_tns_passed_to_sending, none,
-     "Passing %0 value of non-Sendable type %1 as a 'sending' parameter risks causing races inbetween %0 uses and uses reachable from the callee",
+     "Passing %0 value of non-Sendable type %1 as a 'sending' parameter risks "
+     "causing races inbetween %0 uses and uses reachable from the callee",
      (StringRef, Type))
+
 NOTE(regionbasedisolation_typed_tns_passed_to_sending_callee, none,
      "Passing %0 value of non-Sendable type %1 as a 'sending' parameter to %2 %3 risks causing races inbetween %0 uses and uses reachable from %3",
      (StringRef, Type, DescriptiveDeclKind, DeclName))
 
 NOTE(regionbasedisolation_named_transfer_nt_asynclet_capture, none,
       "sending %1 %0 into async let risks causing data races between nonisolated and %1 uses",
       (Identifier, StringRef))
-
-NOTE(regionbasedisolation_typed_use_after_sending, none,
-      "Passing value of non-Sendable type %0 as a 'sending' argument risks causing races in between local and caller code",
-      (Type))
-NOTE(regionbasedisolation_typed_use_after_sending_callee, none,
-      "Passing value of non-Sendable type %0 as a 'sending' argument to %1 %2 risks causing races in between local and caller code",
-      (Type, DescriptiveDeclKind, DeclName))
-
 NOTE(regionbasedisolation_typed_transferneversendable_via_arg, none,
       "sending %0 value of non-Sendable type %1 to %2 callee risks causing races in between %0 and %2 uses",
       (StringRef, Type, ActorIsolation))
 NOTE(regionbasedisolation_typed_transferneversendable_via_arg_callee, none,
       "sending %0 value of non-Sendable type %1 to %2 %3 %4 risks causing races in between %0 and %2 uses",
       (StringRef, Type, ActorIsolation, DescriptiveDeclKind, DeclName))
 
-// Misc Error.
+// Error that is only used when the send non sendable emitter cannot discover any
+// information to give a better diagnostic.
 ERROR(regionbasedisolation_task_or_actor_isolated_transferred, none,
       "task or actor isolated value cannot be sent", ())
 
+//===
+// InOut Sending Emitter
+
+NOTE(regionbasedisolation_inout_sending_must_be_reinitialized, none,
+     "'inout sending' parameter must be reinitialized before function exit with a non-actor isolated value",
+     ())
+ERROR(regionbasedisolation_inout_sending_cannot_be_actor_isolated, none,
+      "'inout sending' parameter %0 cannot be %1at end of function",
+      (Identifier, StringRef))
+NOTE(regionbasedisolation_inout_sending_cannot_be_actor_isolated_note, none,
+      "%1%0 risks causing races in between %1uses and caller uses since caller assumes value is not actor isolated",
+      (Identifier, StringRef))
+
+//===
+// Out Sending
+
+ERROR(regionbasedisolation_out_sending_cannot_be_actor_isolated_type, none,
+      "returning a %1 %0 value as a 'sending' result risks causing data races",
+      (Type, StringRef))
+NOTE(regionbasedisolation_out_sending_cannot_be_actor_isolated_note_type, none,
+      "returning a %1 %0 value risks causing races since the caller assumes the value can be safely sent to other isolation domains",
+      (Type, StringRef))
+ERROR(regionbasedisolation_out_sending_cannot_be_actor_isolated_named, none,
+      "returning %1 %0 as a 'sending' result risks causing data races",
+      (Identifier, StringRef))
+NOTE(regionbasedisolation_out_sending_cannot_be_actor_isolated_note_named, none,
+      "returning %1 %0 risks causing data races since the caller assumes that %0 can be safely sent to other isolation domains",
+      (Identifier, StringRef))
+
+//===----------------------------------------------------------------------===//
+//                           MARK: Misc Diagnostics
+//===----------------------------------------------------------------------===//
+
 // TODO: print the name of the nominal type
 ERROR(deinit_not_visible, none,
       "deinit of non-copyable type not visible in the current module", ())