Merge pull request #41428 from aschwaighofer/update_swiftstdlib_5.6_platforms

Update getSwift56Availability() and add getSwift57Availability() with platform versions

Author: aschwaighofer

include/swift/AST/ASTContext.h

@@ -886,6 +886,10 @@ class ASTContext final {
   /// compiler for the target platform.
   AvailabilityContext getSwift56Availability();
 
+  /// Get the runtime availability of features introduced in the Swift 5.7
+  /// compiler for the target platform.
+  AvailabilityContext getSwift57Availability();
+
   // Note: Update this function if you add a new getSwiftXYAvailability above.
   /// Get the runtime availability for a particular version of Swift (5.0+).
   AvailabilityContext

lib/AST/Availability.cpp

@@ -472,6 +472,23 @@ AvailabilityContext ASTContext::getSwift55Availability() {
 }
 
 AvailabilityContext ASTContext::getSwift56Availability() {
+  auto target = LangOpts.Target;
+
+  if (target.isMacOSX() ) {
+    return AvailabilityContext(
+        VersionRange::allGTE(llvm::VersionTuple(12, 3, 0)));
+  } else if (target.isiOS()) {
+    return AvailabilityContext(
+        VersionRange::allGTE(llvm::VersionTuple(15, 4, 0)));
+  } else if (target.isWatchOS()) {
+    return AvailabilityContext(
+        VersionRange::allGTE(llvm::VersionTuple(8, 5, 0)));
+  } else {
+    return AvailabilityContext::alwaysAvailable();
+  }
+}
+
+AvailabilityContext ASTContext::getSwift57Availability() {
   return getSwiftFutureAvailability();
 }
 
@@ -503,6 +520,7 @@ ASTContext::getSwift5PlusAvailability(llvm::VersionTuple swiftVersion) {
     case 4: return getSwift54Availability();
     case 5: return getSwift55Availability();
     case 6: return getSwift56Availability();
+    case 7: return getSwift57Availability();
     default: break;
     }
   }