Fix for emitting ArrayStride decoration for arrays of opaque types (#7568)

* WIP opaque type decoration fix

* Clearer intent

* Formatting

* Added test for fix

4 files changed, 32 insertions, 1 deletions

diff --git a/source/slang/slang-emit-spirv.cpp b/source/slang/slang-emit-spirv.cpp
index 62c667de1..7f6202a7f 100644
--- a/source/slang/slang-emit-spirv.cpp
+++ b/source/slang/slang-emit-spirv.cpp
@@ -2060,7 +2060,9 @@ struct SPIRVEmitContext : public SourceEmitterBase, public SPIRVEmitSharedContex
                     inst->getOp() == kIROp_ArrayType
                         ? emitOpTypeArray(inst, elementType, irArrayType->getElementCount())
                         : emitOpTypeRuntimeArray(inst, elementType);
-                if (shouldEmitArrayStride(irArrayType->getElementType()))
+                // Arrays of opaque types should not emit a stride
+                if (!isIROpaqueType(elementType) &&
+                    shouldEmitArrayStride(irArrayType->getElementType()))
                 {
                     auto stride = 0;
                     // If the array type has no stride, it indicates that this array type is only
diff --git a/source/slang/slang-ir-util.cpp b/source/slang/slang-ir-util.cpp
index 687841d5e..69bd2c6c2 100644
--- a/source/slang/slang-ir-util.cpp
+++ b/source/slang/slang-ir-util.cpp
@@ -2408,4 +2408,17 @@ bool isSignedType(IRType* type)
     }
 }
 
+bool isIROpaqueType(IRType* type)
+{
+    switch (type->getOp())
+    {
+    case kIROp_TextureType:
+    case kIROp_SamplerStateType:
+    case kIROp_SamplerComparisonStateType:
+        return true;
+    default:
+        return false;
+    }
+}
+
 } // namespace Slang
diff --git a/source/slang/slang-ir-util.h b/source/slang/slang-ir-util.h
index edb8fdf09..e325fbdc2 100644
--- a/source/slang/slang-ir-util.h
+++ b/source/slang/slang-ir-util.h
@@ -421,6 +421,8 @@ constexpr bool anyOf(Range&& range, Predicate&& pred)
 IRType* getUnsignedTypeFromSignedType(IRBuilder* builder, IRType* type);
 
 bool isSignedType(IRType* type);
+
+bool isIROpaqueType(IRType* type);
 } // namespace Slang
 
 #endif
diff --git a/tests/language-feature/constants/unsized-opaque-array.slang b/tests/language-feature/constants/unsized-opaque-array.slang
new file mode 100644
index 000000000..2aab695f6
--- /dev/null
+++ b/tests/language-feature/constants/unsized-opaque-array.slang
@@ -0,0 +1,14 @@
+//TEST:SIMPLE(filecheck=SPIRV): -target spirv -entry main -emit-spirv-directly
+
+// SPIRV-NOT: OpDecorate {{.*}} ArrayStride 8
+layout(binding = 0)
+Texture2D textures[];
+
+RWTexture2D<uint> tex;
+
+[shader("compute")]
+[numthreads(1,1,1)]
+void main(uint3 threadId : SV_DispatchThreadID)
+{
+    tex[threadId.xy] = uint(textures[0][threadId.xy].r);
+}
\ No newline at end of file