Support shader parameters that are an array of existential type. (#1542)

* Support shader parameters that are an array of existential type.

* Rename to getFirstNonExistentialValueCategory

Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 12 insertions, 3 deletions

diff --git a/source/slang/slang-type-layout.cpp b/source/slang/slang-type-layout.cpp
index 46a521f79..88ec5f4f7 100644
--- a/source/slang/slang-type-layout.cpp
+++ b/source/slang/slang-type-layout.cpp
@@ -3489,6 +3489,13 @@ static TypeLayoutResult _createTypeLayout(
             {
                 arrayResourceCount = elementResourceInfo.count;
             }
+            // The second exception to this is arrays of an existential type
+            // where the entire array should be specialized to a single concrete type.
+            //
+            else if (elementResourceInfo.kind == LayoutResourceKind::ExistentialTypeParam)
+            {
+                arrayResourceCount = elementResourceInfo.count;
+            }
             //
             // The next big exception is when we are forming an unbounded-size
             // array and the element type got "adjusted," because that means
@@ -3677,6 +3684,7 @@ static TypeLayoutResult _createTypeLayout(
             typeLayout->rules = rules;
 
             LayoutSize fixedExistentialValueSize = 0;
+            LayoutSize uniformSlotSize = 0;
             bool targetSupportsPointer =
                 isCPUTarget(context.targetReq) || isCUDATarget(context.targetReq);
 
@@ -3689,7 +3697,7 @@ static TypeLayoutResult _createTypeLayout(
                     fixedExistentialValueSize = anyValueAttr->size;
                 }
                 // Append 16 bytes to accommodate RTTI pointer and witness table pointer.
-                auto uniformSlotSize = fixedExistentialValueSize + 16;
+                uniformSlotSize = fixedExistentialValueSize + 16;
                 typeLayout->addResourceUsage(LayoutResourceKind::Uniform, uniformSlotSize);
             }
             typeLayout->addResourceUsage(LayoutResourceKind::ExistentialTypeParam, 1);
@@ -3736,8 +3744,9 @@ static TypeLayoutResult _createTypeLayout(
                     typeLayout->pendingDataTypeLayout = concreteTypeLayout;
                 }
             }
-
-            return TypeLayoutResult(typeLayout, SimpleLayoutInfo());
+            // Interface type occupies a uniform slot for the fixed size storage, with alignment of 4 bytes.
+            return TypeLayoutResult(
+                typeLayout, SimpleLayoutInfo(LayoutResourceKind::Uniform, uniformSlotSize, 4));
         }
         else if( auto enumDeclRef = declRef.as<EnumDecl>() )
         {