ios - 关键字 "device"在Metal Shading Language中是什么意思

Question

关键字“device”在 Metal Shading Language 中的含义是什么？如:

kernel void add_alps_2d_kernel(const device int *vector1 [[buffer(1)]],
                           device int vector2 [[buffer(2)]],
                           uint id [[ thread_position_in_grid ]]) {

}

Answer 1

根据language spec doc

Arguments to Metal graphics and kernel functions declared in a program that are pointers must be declared with the Metal device, threadgroup, threadgroup_imageblock, or constant address space attribute.

此外:

The device address space name refers to buffer memory objects allocated from the device memory pool that are both readable and writeable.

所以它是一个内存规范，指示指针所在的位置。请注意，在地址空间属性之前使用 const 表示它是只读的。您还可以在 Working with memory in Metal 中找到更多信息。