add thrust/PSTL example with particles and tracks

TODO: includes massive hacks to LLAMA.
Using a custom fork of thrust to fix supporting proxy references.

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "examples/raycast/Sponza"]
 	path = examples/raycast/Sponza
 	url = https://github.com/jimmiebergmann/Sponza
+[submodule "thirdparty/thrust"]
+	path = thirdparty/thrust
+	url = https://github.com/bernhardmgruber/thrust.git

CMakeLists.txt

@@ -74,6 +74,7 @@ if (LLAMA_BUILD_EXAMPLES)
 	add_subdirectory("examples/bitpack")
 	add_subdirectory("examples/bytesplit")
 	add_subdirectory("examples/floatpack")
+	add_subdirectory("examples/thrust")
 
 	# alpaka examples
 	find_package(alpaka 0.7.0 QUIET)

examples/thrust/CMakeLists.txt

@@ -0,0 +1,23 @@
+cmake_minimum_required (VERSION 3.15)
+project(llama-thrust CXX CUDA)
+
+set (Thrust_DIR "../../thirdparty/thrust/thrust/cmake/")
+find_package(Thrust REQUIRED CONFIG)
+thrust_create_target(Thrust FROM_OPTIONS)
+find_package(OpenMP REQUIRED)
+if (NOT TARGET llama::llama)
+	find_package(llama REQUIRED)
+endif()
+add_executable(${PROJECT_NAME} thrust.cu ../common/Stopwatch.hpp ../common/hostname.hpp)
+target_compile_features(${PROJECT_NAME} PRIVATE cxx_std_17)
+target_compile_options(${PROJECT_NAME} PUBLIC $<$<COMPILE_LANGUAGE:CUDA>:--expt-extended-lambda --expt-relaxed-constexpr --use_fast_math --ftemplate-backtrace-limit 500>)
+target_link_libraries(${PROJECT_NAME} PRIVATE llama::llama Thrust OpenMP::OpenMP_CXX)
+
+# OpenMP is not added to the compiler commandline by cmake when using nvcc ..
+if (NOT MSVC)
+	find_package(TBB REQUIRED)
+	target_link_libraries(${PROJECT_NAME} PRIVATE TBB::tbb)
+	target_compile_options(${PROJECT_NAME} PUBLIC -Xcompiler -march=native -ffast-math -fopenmp)
+else()
+	target_compile_options(${PROJECT_NAME} PUBLIC -Xcompiler /openmp)
+endif()