Store parameter indices of mutate lifetime dependence specifiers separately from borrow

Author: meg-gupta

include/swift/AST/ExtInfo.h

@@ -158,23 +158,28 @@ class ClangTypeInfo {
 };
 
 class LifetimeDependenceInfo {
-  IndexSubset *copyLifetimeParamIndices;
+  IndexSubset *inheritLifetimeParamIndices;
   IndexSubset *borrowLifetimeParamIndices;
+  IndexSubset *mutateLifetimeParamIndices;
 
 public:
   LifetimeDependenceInfo()
-      : copyLifetimeParamIndices(nullptr), borrowLifetimeParamIndices(nullptr) {
-  }
-  LifetimeDependenceInfo(IndexSubset *copyLifetimeParamIndices,
-                         IndexSubset *borrowLifetimeParamIndices)
-      : copyLifetimeParamIndices(copyLifetimeParamIndices),
-        borrowLifetimeParamIndices(borrowLifetimeParamIndices) {}
+      : inheritLifetimeParamIndices(nullptr),
+        borrowLifetimeParamIndices(nullptr),
+        mutateLifetimeParamIndices(nullptr) {}
+  LifetimeDependenceInfo(IndexSubset *inheritLifetimeParamIndices,
+                         IndexSubset *borrowLifetimeParamIndices,
+                         IndexSubset *mutateLifetimeParamIndices)
+      : inheritLifetimeParamIndices(inheritLifetimeParamIndices),
+        borrowLifetimeParamIndices(borrowLifetimeParamIndices),
+        mutateLifetimeParamIndices(mutateLifetimeParamIndices) {}
 
   operator bool() const { return empty(); }
 
   bool empty() const {
-    return copyLifetimeParamIndices == nullptr &&
-           borrowLifetimeParamIndices == nullptr;
+    return inheritLifetimeParamIndices == nullptr &&
+           borrowLifetimeParamIndices == nullptr &&
+           mutateLifetimeParamIndices == nullptr;
   }
   std::string getString() const;
 };

lib/AST/ExtInfo.cpp

@@ -74,14 +74,18 @@ std::string LifetimeDependenceInfo::getString() const {
     }
     return result;
   };
-  if (!copyLifetimeParamIndices->isEmpty()) {
+  if (!inheritLifetimeParamIndices->isEmpty()) {
     lifetimeDependenceString =
-        "_copy(" + getOnIndices(copyLifetimeParamIndices) + ")";
+        "_inherit(" + getOnIndices(inheritLifetimeParamIndices) + ")";
   }
   if (!borrowLifetimeParamIndices->isEmpty()) {
     lifetimeDependenceString +=
         "_borrow(" + getOnIndices(borrowLifetimeParamIndices) + ")";
   }
+  if (!mutateLifetimeParamIndices->isEmpty()) {
+    lifetimeDependenceString +=
+        "_mutate(" + getOnIndices(mutateLifetimeParamIndices) + ")";
+  }
   return lifetimeDependenceString;
 }
 

lib/Sema/TypeCheckDecl.cpp

@@ -2583,8 +2583,9 @@ llvm::Optional<LifetimeDependenceInfo> validateLifetimeDependenceInfo(
   auto *dc = decl->getDeclContext();
   auto &ctx = dc->getASTContext();
   auto &diags = ctx.Diags;
-  SmallBitVector copyLifetimeParamIndices(afd->getParameters()->size() + 1);
+  SmallBitVector inheritLifetimeParamIndices(afd->getParameters()->size() + 1);
   SmallBitVector borrowLifetimeParamIndices(afd->getParameters()->size() + 1);
+  SmallBitVector mutateLifetimeParamIndices(afd->getParameters()->size() + 1);
 
   auto updateLifetimeDependenceInfo = [&](LifetimeDependenceSpecifier specifier,
                                           unsigned paramIndexToSet,
@@ -2619,18 +2620,19 @@ llvm::Optional<LifetimeDependenceInfo> validateLifetimeDependenceInfo(
                      getOwnershipSpelling(ownership));
       return true;
     }
-    if (copyLifetimeParamIndices.test(paramIndexToSet) ||
+    if (inheritLifetimeParamIndices.test(paramIndexToSet) ||
         borrowLifetimeParamIndices.test(paramIndexToSet)) {
       diags.diagnose(loc, diag::lifetime_dependence_duplicate_param_id);
       return true;
     }
     if (kind == LifetimeDependenceKind::Copy ||
         kind == LifetimeDependenceKind::Consume) {
-      copyLifetimeParamIndices.set(paramIndexToSet);
-    } else {
-      assert(kind == LifetimeDependenceKind::Borrow ||
-             kind == LifetimeDependenceKind::Mutate);
+      inheritLifetimeParamIndices.set(paramIndexToSet);
+    } else if (kind == LifetimeDependenceKind::Borrow) {
       borrowLifetimeParamIndices.set(paramIndexToSet);
+    } else {
+      assert(kind == LifetimeDependenceKind::Mutate);
+      mutateLifetimeParamIndices.set(paramIndexToSet);
     }
     return false;
   };
@@ -2691,8 +2693,9 @@ llvm::Optional<LifetimeDependenceInfo> validateLifetimeDependenceInfo(
   }
 
   return LifetimeDependenceInfo(
-      IndexSubset::get(ctx, copyLifetimeParamIndices),
-      IndexSubset::get(ctx, borrowLifetimeParamIndices));
+      IndexSubset::get(ctx, inheritLifetimeParamIndices),
+      IndexSubset::get(ctx, borrowLifetimeParamIndices),
+      IndexSubset::get(ctx, mutateLifetimeParamIndices));
 }
 
 static void maybeAddParameterIsolation(AnyFunctionType::ExtInfoBuilder &infoBuilder,