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@joyeamd joyeamd commented Oct 11, 2025

update s_barrier's logic in gfx12, use s_wait_loadcnt_dscnt instead of s_waitcnt; because s_waitcnt in gfx12 is equivalent to s_wait_idle,  which means wait for all activity in the wave to be complete (all dependency and memory counters at zero). This will hurt performance.

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change s_waitcnt's logic in gfx1250

change s_waitcnt's logic in gfx1250

update comment
waitcnt_arg::from_expcnt<expcnt>() |
waitcnt_arg::from_lgkmcnt<lgkmcnt>();

asm volatile("s_wait_loadcnt_dscnt %0" : : "n"(wait_mask) : "memory");
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Do we have a builtin for this instruction? We could also ask compiler to add one, if the answer is no.

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There is no builtin for s_wait_loadcnt_dscnt.

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