[region-isolation] Move computation of SILIsolationInfo for a SILFunctionArgument onto SILIsolationInfo::get(...).

Author: gottesmm

include/swift/SILOptimizer/Utils/PartitionUtils.h

@@ -257,6 +257,9 @@ class SILIsolationInfo {
   /// Attempt to infer the isolation region info for \p inst.
   static SILIsolationInfo get(SILInstruction *inst);
 
+  /// Attempt to infer the isolation region info for \p arg.
+  static SILIsolationInfo get(SILFunctionArgument *arg);
+
   bool operator==(const SILIsolationInfo &other) const {
     if (getKind() != other.getKind())
       return false;

lib/SILOptimizer/Analysis/RegionAnalysis.cpp

@@ -3383,39 +3383,8 @@ TrackableValue RegionAnalysisValueMap::getTrackableValue(
   if (auto *fArg =
           dyn_cast<SILFunctionArgument>(iter.first->first.getValue())) {
     if (!isTransferrableFunctionArgument(fArg)) {
-      auto *self =
-          iter.first->first.getValue()->getFunction()->maybeGetSelfArgument();
-      NominalTypeDecl *nomDecl = nullptr;
-      if (self &&
-          ((nomDecl = self->getType().getNominalOrBoundGenericNominal()))) {
-        iter.first->getSecond().mergeIsolationRegionInfo(
-            SILIsolationInfo::getActorIsolated(nomDecl));
-        return {iter.first->first, iter.first->second};
-      }
-
-      // See if we can infer actor isolation from our fArg's value decl.
-      //
-      // This handles functions generated by SILGen with global actors, but
-      // doesn't handle SIL written global actors since function arguments
-      // parsed from SIL do not have associated var decls.
-      if (auto *decl = fArg->getDecl()) {
-        auto isolation =
-            swift::getActorIsolation(const_cast<ValueDecl *>(decl));
-        if (!bool(isolation)) {
-          if (auto *dc = decl->getDeclContext()) {
-            isolation = swift::getActorIsolationOfContext(dc);
-          }
-        }
-
-        if (isolation.isActorIsolated()) {
-          iter.first->getSecond().mergeIsolationRegionInfo(
-              SILIsolationInfo::getActorIsolated(isolation));
-          return {iter.first->first, iter.first->second};
-        }
-      }
-
       iter.first->getSecond().mergeIsolationRegionInfo(
-          SILIsolationInfo::getTaskIsolated(fArg));
+          SILIsolationInfo::get(fArg));
       return {iter.first->first, iter.first->second};
     }
   }

lib/SILOptimizer/Utils/PartitionUtils.cpp

@@ -63,3 +63,26 @@ SILIsolationInfo SILIsolationInfo::get(SILInstruction *inst) {
   // cannot cross an isolation domain.
   return SILIsolationInfo();
 }
+
+SILIsolationInfo SILIsolationInfo::get(SILFunctionArgument *arg) {
+  if (auto *self = arg->getFunction()->maybeGetSelfArgument()) {
+    if (auto *nomDecl = self->getType().getNominalOrBoundGenericNominal()) {
+      return SILIsolationInfo::getActorIsolated(nomDecl);
+    }
+  }
+
+  if (auto *decl = arg->getDecl()) {
+    auto isolation = swift::getActorIsolation(const_cast<ValueDecl *>(decl));
+    if (!bool(isolation)) {
+      if (auto *dc = decl->getDeclContext()) {
+        isolation = swift::getActorIsolationOfContext(dc);
+      }
+    }
+
+    if (isolation.isActorIsolated()) {
+      return SILIsolationInfo::getActorIsolated(isolation);
+    }
+  }
+
+  return SILIsolationInfo::getTaskIsolated(arg);
+}