Merge pull request #656 from Eichenherz/Intrinsics

Added bit_field intrisic

Author: devshgraphicsprogramming

include/nbl/builtin/hlsl/cpp_compat/intrinsics.h

@@ -71,6 +71,11 @@ inline matrix<T,M,N> transpose(const matrix<T,N,M>& m)
     return glm::transpose(reinterpret_cast<typename matrix<T,N,M>::Base const&>(m));
 }
 
+template<typename T>
+inline T bitfieldExtract( T val, uint32_t offsetBits, uint32_t numBits )
+{
+    return glm::bitfieldExtract( val, int32_t( offsetBits ), int32_t( numBits ) );
+}
 
 #undef NBL_BIT_OP_GLM_PASSTHROUGH
 #undef NBL_SIMPLE_GLM_PASSTHROUGH

include/nbl/builtin/hlsl/glsl_compat/core.hlsl

@@ -6,6 +6,7 @@
 
 #include "nbl/builtin/hlsl/cpp_compat.hlsl"
 #include "nbl/builtin/hlsl/spirv_intrinsics/core.hlsl"
+#include "nbl/builtin/hlsl/type_traits.hlsl"
 
 namespace nbl 
 {
@@ -83,6 +84,50 @@ void tess_ctrl_barrier() {
 void memoryBarrierShared() {
     spirv::memoryBarrier(spv::ScopeDevice, spv::MemorySemanticsAcquireReleaseMask | spv::MemorySemanticsWorkgroupMemoryMask);
 }
+
+namespace impl 
+{
+
+template<typename T, bool isSigned, bool isIntegral>
+struct bitfieldExtract {};
+
+template<typename T, bool isSigned>
+struct bitfieldExtract<T, isSigned, false>
+{
+    T operator()( T val, uint32_t offsetBits, uint32_t numBits )
+    {
+        static_assert( is_integral<T>::value, "T is not an integral type!" );
+        return val;
+    }
+};
+
+template<typename T>
+struct bitfieldExtract<T, true, true>
+{
+    T operator()( T val, uint32_t offsetBits, uint32_t numBits )
+    {
+        return spirv::bitFieldSExtract<T>( val, offsetBits, numBits );
+    }
+};
+
+template<typename T>
+struct bitfieldExtract<T, false, true>
+{
+    T operator()( T val, uint32_t offsetBits, uint32_t numBits )
+    {
+        return spirv::bitFieldUExtract<T>( val, offsetBits, numBits );
+    } 
+};
+
+}
+
+template<typename T>
+T bitfieldExtract( T val, uint32_t offsetBits, uint32_t numBits )
+{
+    return impl::bitfieldExtract<T, is_signed<T>::value, is_integral<T>::value>::template 
+        ( val, offsetBits, numBits );
+}
+
 #endif
 
 }

include/nbl/builtin/hlsl/spirv_intrinsics/core.hlsl

@@ -129,6 +129,15 @@ void memoryBarrier(uint32_t memoryScope, uint32_t memorySemantics);
 template<class T, class U>
 [[vk::ext_instruction(spv::OpBitcast)]]
 T bitcast(U);
+
+template<typename Unsigned>
+[[vk::ext_instruction( spv::OpBitFieldUExtract )]]
+Unsigned bitFieldUExtract( Unsigned val, uint32_t offsetBits, uint32_t numBits );
+
+template<typename Signed>
+[[vk::ext_instruction( spv::OpBitFieldSExtract )]]
+Signed bitFieldSExtract( Signed val, uint32_t offsetBits, uint32_t numBits );
+
 }
 #endif
 }