Atomic types

Atomic operations only work on 32-bit integers.

An atomic type is specified as atomic<T> , where T is i32 or u32.

An atomic type can only appear in the store type for a variable in the workgroup or storage address space.

Atomic types are not constructible, and so they cannot directly be used:

in an expression,
passed as a function argument,
returned from a function,
assigned to a variable, or
used as an initializer expression.

Remember, only atomic builtin functions operate on atomic types, and only when accessed from memory. Pass a pointer to the memory to the builtin function.

var<workgroup> item_sum: atomic<i32>; fn what_is_the_sum_now() -> i32 { return atomicLoad(&item_sum); } fn reset_sum() { atomicStore(&item_sum, 0); } struct Queue { read_count: atomic<u32>, write_count: atomic<u32>, items: array<i32>, } @group(0) @binding(0) var<storage,read_write> work: Queue; //var<private> bad_private: atomic<u32>; // Error: wrong address space fn helper() { //var bad: atomic<u32>; // Error: wrong address space }