Allow tuples to work with initializer list. (#6301)

* Allow tuples to work with initiailizer list.

* Update definition of C-Style types.

2 files changed, 58 insertions, 3 deletions

diff --git a/source/slang/slang-check-conversion.cpp b/source/slang/slang-check-conversion.cpp
index 6bbdc1477..6dda9c1ea 100644
--- a/source/slang/slang-check-conversion.cpp
+++ b/source/slang/slang-check-conversion.cpp
@@ -238,6 +238,21 @@ bool SemanticsVisitor::isCStyleType(Type* type, HashSet<Type*>& isVisit)
         return cacheResult(true);
 
 
+    // A tuple type is C-style if all of its members are C-style.
+    if (auto tupleType = as<TupleType>(type))
+    {
+        for (Index i = 0; i < tupleType->getMemberCount(); i++)
+        {
+            auto elementType = tupleType->getMember(i);
+            // Avoid infinite loop in case of circular reference.
+            if (isVisit.contains(elementType))
+                return cacheResult(false);
+            if (!isCStyleType(elementType, isVisit))
+                return cacheResult(false);
+        }
+        return cacheResult(true);
+    }
+
     if (auto structDecl = isDeclRefTypeOf<StructDecl>(type).getDecl())
     {
         // 2. It cannot have inheritance, but inherit from interface is fine.
@@ -299,6 +314,7 @@ bool SemanticsVisitor::isCStyleType(Type* type, HashSet<Type*>& isVisit)
         if (!isCStyleType(elementType, isVisit))
             return cacheResult(false);
     }
+
     return cacheResult(true);
 }
 
@@ -700,6 +716,28 @@ bool SemanticsVisitor::_readAggregateValueFromInitializerList(
             }
         }
     }
+    else if (auto tupleType = as<TupleType>(toType))
+    {
+        for (Index ee = 0; ee < tupleType->getMemberCount(); ++ee)
+        {
+            auto elementType = tupleType->getMember(ee);
+            Expr* coercedArg = nullptr;
+            bool argResult = _readValueFromInitializerList(
+                elementType,
+                outToExpr ? &coercedArg : nullptr,
+                fromInitializerListExpr,
+                ioArgIndex);
+
+            // No point in trying further if any argument fails
+            if (!argResult)
+                return false;
+
+            if (coercedArg)
+            {
+                coercedArgs.add(coercedArg);
+            }
+        }
+    }
     else if (auto toDeclRefType = as<DeclRefType>(toType))
     {
         auto toTypeDeclRef = toDeclRefType->getDeclRef();
diff --git a/source/slang/slang-lower-to-ir.cpp b/source/slang/slang-lower-to-ir.cpp
index cac157f9b..36003dcb2 100644
--- a/source/slang/slang-lower-to-ir.cpp
+++ b/source/slang/slang-lower-to-ir.cpp
@@ -4701,6 +4701,16 @@ struct ExprLoweringVisitorBase : public ExprVisitor<Derived, LoweredValInfo>
         {
             return LoweredValInfo::simple(getBuilder()->getNullPtrValue(irType));
         }
+        else if (auto tupleType = as<TupleType>(type))
+        {
+            List<IRInst*> args;
+            for (Index i = 0; i < tupleType->getMemberCount(); i++)
+            {
+                args.add(getSimpleVal(context, getDefaultVal(tupleType->getMember(i))));
+            }
+            return LoweredValInfo::simple(
+                getBuilder()->emitMakeTuple(irType, args.getCount(), args.getBuffer()));
+        }
         else if (auto declRefType = as<DeclRefType>(type))
         {
             DeclRef<Decl> declRef = declRefType->getDeclRef();
@@ -4925,9 +4935,16 @@ struct ExprLoweringVisitorBase : public ExprVisitor<Derived, LoweredValInfo>
                         args.add(irDefaultValue);
                     }
                 }
-
-                return LoweredValInfo::simple(
-                    getBuilder()->emitMakeStruct(irType, args.getCount(), args.getBuffer()));
+                if (as<TupleType>(type))
+                {
+                    return LoweredValInfo::simple(
+                        getBuilder()->emitMakeTuple(irType, args.getCount(), args.getBuffer()));
+                }
+                else
+                {
+                    return LoweredValInfo::simple(
+                        getBuilder()->emitMakeStruct(irType, args.getCount(), args.getBuffer()));
+                }
             }
         }