[rbi] Change Region Based Isolation for closures to not use the AST and instead just use SIL.

The reason why I am doing this is that in certain cases the AST captures indices
will never actually line up with partial apply capture indices since we seem to
"smush" together closures and locally defined functions.

NOTE: The reason for the really small amount of test changes is that this change
does not change the actual output by design. The only cases I had to change were
a case where we began to emit a better diagnostic and also where I added code
coverage around _ and let _ since those require ignored_use to be implemented so
that they would be diagnosed (previously we just did not emit anything so we
couldn't emit the diagnostic at the SIL level).

rdar://142661388

Author: gottesmm

include/swift/AST/DiagnosticsSIL.def

@@ -1056,6 +1056,12 @@ NOTE(regionbasedisolation_typed_tns_passed_to_sending_closure_helper_have_value_
 NOTE(regionbasedisolation_typed_tns_passed_to_sending_closure_helper_multiple_value, none,
      "closure captures non-Sendable %0",
      (DeclName))
+NOTE(regionbasedisolation_closure_captures, none,
+     "closure captures %0",
+     (DeclName))
+NOTE(regionbasedisolation_closure_captures_actor, none,
+     "closure captures %0 allowing access to %1 state within the closure",
+     (DeclName, StringRef))
 
 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",

include/swift/SIL/InstructionUtils.h

@@ -129,6 +129,11 @@ bool isEndOfScopeMarker(SILInstruction *user);
 /// only used in recognizable patterns without otherwise "escaping".
 bool isIncidentalUse(SILInstruction *user);
 
+/// Returns true if this is a move only wrapper use.
+///
+/// E.x.: moveonlywrapper_to_copyable_addr, copyable_to_moveonlywrapper_value
+bool isMoveOnlyWrapperUse(SILInstruction *user);
+
 /// Return true if the given `user` instruction modifies the value's refcount
 /// without propagating the value or having any other effect aside from
 /// potentially destroying the value itself (and executing associated cleanups).

include/swift/SILOptimizer/Utils/PartitionUtils.h

@@ -1374,6 +1374,12 @@ struct PartitionOpEvaluator {
       Region sentRegion = p.getRegion(sentElement);
       bool isClosureCapturedElt = false;
       SILDynamicMergedIsolationInfo sentRegionIsolation;
+
+      // TODO: Today we only return the first element in our region that has
+      // some form of isolation. This causes us to in the case of sending
+      // partial_applies to only emit a diagnostic for the first element in the
+      // capture list of the partial_apply. If we returned a list of potential
+      // errors... we could emit the error for each capture individually.
       auto pairOpt = getIsolationRegionInfo(sentRegion, op.getSourceOp());
       if (!pairOpt) {
         return handleError(UnknownCodePatternError(op));

lib/SIL/Utils/InstructionUtils.cpp

@@ -339,6 +339,19 @@ bool swift::isIncidentalUse(SILInstruction *user) {
          isa<IgnoredUseInst>(user);
 }
 
+bool swift::isMoveOnlyWrapperUse(SILInstruction *user) {
+  switch (user->getKind()) {
+  case SILInstructionKind::MoveOnlyWrapperToCopyableValueInst:
+  case SILInstructionKind::MoveOnlyWrapperToCopyableBoxInst:
+  case SILInstructionKind::MoveOnlyWrapperToCopyableAddrInst:
+  case SILInstructionKind::CopyableToMoveOnlyWrapperValueInst:
+  case SILInstructionKind::CopyableToMoveOnlyWrapperAddrInst:
+    return true;
+  default:
+    return false;
+  }
+}
+
 bool swift::onlyAffectsRefCount(SILInstruction *user) {
   switch (user->getKind()) {
   default: