correct small bugs in nbl::hlsl:::mpl

Author: devsh

include/nbl/builtin/hlsl/bda/__ref.hlsl

@@ -57,6 +57,7 @@ struct __base_ref
 };
 
 // TODO: I wish HLSL had some things like C++ which would allow you to make a "stack only"/non-storable type
+// NOTE: I guess there's the Function/Private storage space variables?
 template<typename T, uint32_t alignment=alignment_of_v<T>, bool _restrict=false>
 struct __ref : __base_ref<T,alignment,_restrict>
 {

include/nbl/builtin/hlsl/bda/struct_declare.hlsl

@@ -58,14 +58,9 @@ namespace impl
 template<typename T, uint32_t N>
 struct default_alignment
 {
-    NBL_CONSTEXPR_STATIC_INLINE uint32_t value = mpl::max_v<uint32_t,member_alignment_v<T,N-1>,member_alignment_v<T,N-2> >;
+    NBL_CONSTEXPR_STATIC_INLINE uint32_t value = mpl::max_v<uint32_t,member_alignment_v<T,N-1>,default_alignment<T,N-1>::value>;
 };
-template<typename T>
-struct default_alignment<T,1>
-{
-    NBL_CONSTEXPR_STATIC_INLINE uint32_t value = member_alignment_v<T,0>;
-};
-// le invalid value
+// le invalid values
 template<typename T>
 struct default_alignment<T,0>
 {

include/nbl/builtin/hlsl/mpl.hlsl

@@ -74,7 +74,7 @@ NBL_CONSTEXPR T rotr_v = rotr<T,X,S>::value;
 template<uint64_t X, uint64_t M>
 struct align_up
 {
-    NBL_CONSTEXPR_STATIC_INLINE uint64_t value = (X+M-1)/M;
+    NBL_CONSTEXPR_STATIC_INLINE uint64_t value = X ? (((X-1)/M+1)*M):0;
 };
 template<uint64_t X, uint64_t M>
 NBL_CONSTEXPR uint64_t align_up_v = align_up<X,M>::value;