radv: Optimize memcpy in write_image_descriptor
Optimize memcpy in write_image_descriptor
The size parameter can only take certain values. Make this visible to the compiler to encourage it to inline the memcpy.
330% gain on vkoverhead test descriptor_16combined_sampler on i5-2500 CPU.
N Min Max Median Avg Stddev
x 50 876 913 897 896.06 6.6067683
+ 50 3895 3933 3928 3925.28 7.461575
Difference at 95.0% confidence
3029.22 +/- 2.79631
338.06% +/- 0.312067%
(Student's t, pooled s = 7.04714)
Are these all possible size values? Should the fallback call memcpy with the unknown size value?