Practice codes for GPU optimization.

• Example codes I have tried while studying GPU programming with CUDA.
• From resources usch as, "Programming Massively Parallel Processors" (4th edition), cuda_training_series from NVIDIA, and some other interesting problems for practice such as image_rotation.
• For each code, there are multiple kernels with different optimizations enabled based on preprocessor directives. Check them at the beginning of the code before compiling.
• e.g.: nvcc -arch=sm_70 -DTILED -o solver.x matmul.cu