PTX ISA 之 volatile 的用法

字面意思

挥发性的，不稳定的

用法

用于ld/st指令

ld.volatile{.ss}.type d, [a]; // load from address ld.volatile{.ss}.vec.type d, [a]; // vector load from addr

An ld.volatile operation is always performed and it will not be reordered with respect to other volatile operations to the same memory location. volatile and non-volatile load operations to the same memory location may be reordered.

关于volatile 类型的顺序问题，同是volatile类型的对同一数据访问，是不可以重排序，与non-volatile的读操作是可以重排序的。

ld.volatile may be used only with .global and .shared spaces and with generic addressing, where the address points to .global or .shared space. Cache operations are not permitted with ld.volatile.

cache 操作是不允许使用volatile类型的，换句话说，此操作是不会caching 的，只能在内存中操作。

An st.volatile operation is always performed and it will not be reordered with respect to other volatile operations to the same memory location.Generic addressing may be used with st.volatile. Cache operations are not permitted with st.volatile.

st 操作类似ld