Merge pull request swiftlang#36489 from aschwaighofer/remove_error_from_async_context

Remove unused error result storage from AsyncContext

Author: aschwaighofer

lib/IRGen/GenCall.cpp

@@ -146,13 +146,6 @@ irgen::getAsyncContextLayout(IRGenModule &IGM, CanSILFunctionType originalType,
     typeInfos.push_back(&ti);
   }
 
-  //   SwiftError **errorResult;
-  auto errorCanType = IGM.Context.getExceptionType();
-  auto errorType = SILType::getPrimitiveObjectType(errorCanType);
-  auto &errorTypeInfo =
-      IGM.getTypeInfoForLowered(CanInOutType::get(errorCanType));
-  typeInfos.push_back(&errorTypeInfo);
-  valTypes.push_back(errorType);
   // Add storage for data used by runtime entry points.
   // See TaskFutureWaitAsyncContext.
   if (kind.isSpecial()) {
@@ -196,22 +189,18 @@ irgen::getAsyncContextLayout(IRGenModule &IGM, CanSILFunctionType originalType,
     } break;
     }
   }
-  bool canHaveValidError = substitutedType->hasErrorResult();
   return AsyncContextLayout(IGM, LayoutStrategy::Optimal, valTypes, typeInfos,
-                            originalType, substitutedType, substitutionMap,
-                            errorType, canHaveValidError);
+                            originalType, substitutedType, substitutionMap);
 }
 
 AsyncContextLayout::AsyncContextLayout(
     IRGenModule &IGM, LayoutStrategy strategy, ArrayRef<SILType> fieldTypes,
     ArrayRef<const TypeInfo *> fieldTypeInfos, CanSILFunctionType originalType,
-    CanSILFunctionType substitutedType, SubstitutionMap substitutionMap,
-    SILType errorType, bool canHaveValidError)
+    CanSILFunctionType substitutedType, SubstitutionMap substitutionMap)
     : StructLayout(IGM, /*decl=*/nullptr, LayoutKind::NonHeapObject, strategy,
                    fieldTypeInfos, /*typeToFill*/ nullptr),
       originalType(originalType), substitutedType(substitutedType),
-      substitutionMap(substitutionMap), errorType(errorType),
-      canHaveValidError(canHaveValidError)  {
+      substitutionMap(substitutionMap)  {
 #ifndef NDEBUG
   assert(fieldTypeInfos.size() == fieldTypes.size() &&
          "type infos don't match types");
@@ -2317,13 +2306,6 @@ class AsyncCallEmission final : public CallEmission {
         IGF.Builder.CreateZExt(dynamicContextSize32, IGF.IGM.SizeTy);
     contextBuffer = emitAllocAsyncContext(IGF, dynamicContextSize);
     context = layout.emitCastTo(IGF, contextBuffer.getAddress());
-    if (layout.canHaveError()) {
-      auto fieldLayout = layout.getErrorLayout();
-      auto ptrToAddr =
-          fieldLayout.project(IGF, context, /*offsets*/ llvm::None);
-      auto errorSlot = IGF.getAsyncCalleeErrorResultSlot(layout.getErrorType());
-      IGF.Builder.CreateStore(errorSlot.getAddress(), ptrToAddr);
-    }
   }
   void end() override {
     assert(contextBuffer.isValid());

lib/IRGen/GenCall.h

@@ -71,7 +71,6 @@ namespace irgen {
   //   SwiftPartialFunction * __ptrauth(...) returnToCaller;
   //   SwiftActor * __ptrauth(...) callerActor;
   //   SwiftPartialFunction * __ptrauth(...) yieldToCaller?;
-  //   SwiftError **errorResult;
   // };
   struct AsyncContextLayout : StructLayout {
     struct ArgumentInfo {
@@ -91,13 +90,10 @@ namespace irgen {
       Parent = 1,
       ResumeParent = 1,
       ResumeParentExecutor = 1,
-      Error = 1,
     };
     CanSILFunctionType originalType;
     CanSILFunctionType substitutedType;
     SubstitutionMap substitutionMap;
-    SILType errorType;
-    bool canHaveValidError;
 
     unsigned getParentIndex() { return (unsigned)FixedIndex::Parent; }
     unsigned getResumeParentIndex() {
@@ -120,16 +116,12 @@ namespace irgen {
       return getElement(getResumeParentExecutorIndex());
     }
     ElementLayout getFlagsLayout() { return getElement(getFlagsIndex()); }
-    bool canHaveError() { return canHaveValidError; }
-    ElementLayout getErrorLayout() { return getElement(getErrorIndex()); }
-    unsigned getErrorCount() { return (unsigned)FixedCount::Error; }
-    SILType getErrorType() { return errorType; }
 
     AsyncContextLayout(
         IRGenModule &IGM, LayoutStrategy strategy, ArrayRef<SILType> fieldTypes,
         ArrayRef<const TypeInfo *> fieldTypeInfos,
         CanSILFunctionType originalType, CanSILFunctionType substitutedType,
-        SubstitutionMap substitutionMap, SILType errorType, bool canHaveValidError);
+        SubstitutionMap substitutionMap);
   };
 
   AsyncContextLayout getAsyncContextLayout(IRGenModule &IGM,

test/IRGen/async.swift

@@ -17,7 +17,7 @@ public class SomeClass {}
 public func task_future_wait(_ task: __owned SomeClass) async throws -> Int
 
 // CHECK: define{{.*}} swift{{(tail)?}}cc void @"$s5async8testThisyyAA9SomeClassCnYF"(%swift.context* swiftasync %0{{.*}}
-// CHECK-64: call swiftcc i8* @swift_task_alloc(i64 64)
+// CHECK-64: call swiftcc i8* @swift_task_alloc(i64 56)
 // CHECK: {{(must)?}}tail call swift{{(tail)?}}cc void @swift_task_future_wait(
 public func testThis(_ task: __owned SomeClass) async {
   do {