Relax restriction on using link-time types for shader parameters. (#8387)

This change relaxes a previous restriction on link-time types and
constants, so that we now allow them to be used to define shader
parameters.

Doing so will result in a parameter layout that is incomplete prior to
linking. The PR added a test to call the reflection API on a fully
linked program and ensure that we can report correct binding info.

5 files changed, 18 insertions, 34 deletions

diff --git a/source/slang/slang-check-decl.cpp b/source/slang/slang-check-decl.cpp
index 4711eaddd..4362f0926 100644
--- a/source/slang/slang-check-decl.cpp
+++ b/source/slang/slang-check-decl.cpp
@@ -2922,13 +2922,6 @@ void SemanticsDeclBodyVisitor::checkVarDeclCommon(VarDeclBase* varDecl)
 
     if (auto elementType = getConstantBufferElementType(varDecl->getType()))
     {
-        if (doesTypeHaveTag(elementType, TypeTag::Incomplete))
-        {
-            getSink()->diagnose(
-                varDecl->type.exp->loc,
-                Diagnostics::incompleteTypeCannotBeUsedInBuffer,
-                elementType);
-        }
         if (doesTypeHaveTag(elementType, TypeTag::Unsized))
         {
             // If the element type is unsized, it can only be an array of resource types that we can
@@ -2947,17 +2940,6 @@ void SemanticsDeclBodyVisitor::checkVarDeclCommon(VarDeclBase* varDecl)
             }
         }
     }
-    else if (varDecl->findModifier<HLSLUniformModifier>())
-    {
-        auto varType = varDecl->getType();
-        if (doesTypeHaveTag(varType, TypeTag::Incomplete))
-        {
-            getSink()->diagnose(
-                varDecl->type.exp->loc,
-                Diagnostics::incompleteTypeCannotBeUsedInUniformParameter,
-                varType);
-        }
-    }
     maybeRegisterDifferentiableType(getASTBuilder(), varDecl->getType());
 }
 
diff --git a/source/slang/slang-diagnostic-defs.h b/source/slang/slang-diagnostic-defs.h
index 2febd317e..64b1423ac 100644
--- a/source/slang/slang-diagnostic-defs.h
+++ b/source/slang/slang-diagnostic-defs.h
@@ -1455,16 +1455,6 @@ DIAGNOSTIC(
     "modifier '$0' is redundant or conflicting with existing modifier '$1'")
 DIAGNOSTIC(31203, Error, cannotExportIncompleteType, "cannot export incomplete type '$0'")
 DIAGNOSTIC(
-    31204,
-    Error,
-    incompleteTypeCannotBeUsedInBuffer,
-    "incomplete type '$0' cannot be used in a buffer")
-DIAGNOSTIC(
-    31205,
-    Error,
-    incompleteTypeCannotBeUsedInUniformParameter,
-    "incomplete type '$0' cannot be used in a uniform parameter")
-DIAGNOSTIC(
     31206,
     Error,
     memoryQualifierNotAllowedOnANonImageTypeParameter,
diff --git a/source/slang/slang-parameter-binding.cpp b/source/slang/slang-parameter-binding.cpp
index 4b91056fc..b79f96022 100644
--- a/source/slang/slang-parameter-binding.cpp
+++ b/source/slang/slang-parameter-binding.cpp
@@ -2420,7 +2420,7 @@ static RefPtr<TypeLayout> processEntryPointVaryingParameter(
         if (auto structDeclRef = declRef.as<StructDecl>())
         {
             RefPtr<StructTypeLayout> structLayout = new StructTypeLayout();
-            structLayout->type = type;
+            structLayout->type = declRefType;
 
             // We will recursively walk the fields of a `struct` type
             // to compute layouts for those fields.
diff --git a/source/slang/slang-type-layout.cpp b/source/slang/slang-type-layout.cpp
index efd41bd86..fb40382c5 100644
--- a/source/slang/slang-type-layout.cpp
+++ b/source/slang/slang-type-layout.cpp
@@ -4918,7 +4918,8 @@ static TypeLayoutResult _createTypeLayout(TypeLayoutContext& context, Type* type
     else if (auto vecType = as<VectorExpressionType>(type))
     {
         auto elementType = vecType->getElementType();
-        size_t elementCount = (size_t)getIntVal(vecType->getElementCount());
+        size_t elementCount =
+            (size_t)getIntVal(context.tryResolveLinkTimeVal(vecType->getElementCount()));
 
         auto element = _createTypeLayout(context, elementType);
 
@@ -4944,8 +4945,9 @@ static TypeLayoutResult _createTypeLayout(TypeLayoutContext& context, Type* type
     }
     else if (auto matType = as<MatrixExpressionType>(type))
     {
-        size_t rowCount = (size_t)getIntVal(matType->getRowCount());
-        size_t colCount = (size_t)getIntVal(matType->getColumnCount());
+        size_t rowCount = (size_t)getIntVal(context.tryResolveLinkTimeVal(matType->getRowCount()));
+        size_t colCount =
+            (size_t)getIntVal(context.tryResolveLinkTimeVal(matType->getColumnCount()));
 
         auto elementType = matType->getElementType();
         auto elementResult = _createTypeLayout(context, elementType);
@@ -5031,7 +5033,7 @@ static TypeLayoutResult _createTypeLayout(TypeLayoutContext& context, Type* type
             context,
             arrayType,
             arrayType->getElementType(),
-            arrayType->getElementCount());
+            context.tryResolveLinkTimeVal(arrayType->getElementCount()));
     }
     else if (auto atomicType = as<AtomicType>(type))
     {
@@ -5181,7 +5183,7 @@ static TypeLayoutResult _createTypeLayout(TypeLayoutContext& context, Type* type
             StructTypeLayoutBuilder typeLayoutBuilder;
             StructTypeLayoutBuilder pendingDataTypeLayoutBuilder;
 
-            typeLayoutBuilder.beginLayout(type, rules);
+            typeLayoutBuilder.beginLayout(declRefType, rules);
             auto typeLayout = typeLayoutBuilder.getTypeLayout();
 
             _addLayout(context, type, typeLayout);
diff --git a/source/slang/slang-type-layout.h b/source/slang/slang-type-layout.h
index bcb842013..84840c043 100644
--- a/source/slang/slang-type-layout.h
+++ b/source/slang/slang-type-layout.h
@@ -1231,6 +1231,16 @@ struct TypeLayoutContext
         }
         return result;
     }
+
+    IntVal* tryResolveLinkTimeVal(IntVal* inVal) const
+    {
+        if (!programLayout)
+            return inVal;
+        auto constIntVal = programLayout->getProgram()->tryFoldIntVal(inVal);
+        if (constIntVal)
+            return constIntVal;
+        return inVal;
+    }
 };
 
 //