[Async CC] Add Flags to context.

Author: nate-chandler

lib/IRGen/GenCall.cpp

@@ -131,6 +131,16 @@ AsyncContextLayout irgen::getAsyncContextLayout(
   // ExecutorRef ResumeParentExecutor;
   addExecutor();
 
+  // AsyncContextFlags Flags;
+  {
+    auto ty = SILType::getPrimitiveObjectType(
+        BuiltinIntegerType::get(32, IGF.IGM.IRGen.SIL.getASTContext())
+            ->getCanonicalType());
+    const auto &ti = IGF.IGM.getTypeInfo(ty);
+    valTypes.push_back(ty);
+    typeInfos.push_back(&ti);
+  }
+
   //   SwiftError *errorResult;
   auto errorCanType = IGF.IGM.Context.getExceptionType();
   auto errorType = SILType::getPrimitiveObjectType(errorCanType);

lib/IRGen/GenCall.h

@@ -96,7 +96,8 @@ namespace irgen {
       Parent = 0,
       ResumeParent = 1,
       ResumeParentExecutor = 2,
-      Error = 3,
+      Flags = 3,
+      Error = 4,
     };
     enum class FixedCount : unsigned {
       Parent = 1,
@@ -124,6 +125,7 @@ namespace irgen {
     unsigned getResumeParentExecutorIndex() {
       return (unsigned)FixedIndex::ResumeParentExecutor;
     }
+    unsigned getFlagsIndex() { return (unsigned)FixedIndex::Flags; }
     unsigned getErrorIndex() { return (unsigned)FixedIndex::Error; }
     unsigned getFirstIndirectReturnIndex() {
       return getErrorIndex() + getErrorCount();
@@ -176,6 +178,7 @@ namespace irgen {
     ElementLayout getResumeParentExecutorLayout() {
       return getElement(getResumeParentExecutorIndex());
     }
+    ElementLayout getFlagsLayout() { return getElement(getFlagsIndex()); }
     bool canHaveError() { return canHaveValidError; }
     ElementLayout getErrorLayout() { return getElement(getErrorIndex()); }
     unsigned getErrorCount() { return (unsigned)FixedCount::Error; }