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waitcnt

Counts of outstanding instructions to wait for.

The bits of this operand have the following meaning:

Bits Description
3:0 VM_CNT: vector memory operations count.
6:4 EXP_CNT: export count.
11:8 LGKM_CNT: LDS, GDS, Constant and Message count.

This operand may be specified as a positive 16-bit :ref:`integer_number<amdgpu_synid_integer_number>` or as a combination of the following symbolic helpers:

Syntax Description
vmcnt(<N>) VM_CNT value. N must not exceed the largest VM_CNT value.
expcnt(<N>) EXP_CNT value. N must not exceed the largest EXP_CNT value.
lgkmcnt(<N>) LGKM_CNT value. N must not exceed the largest LGKM_CNT value.
vmcnt_sat(<N>) VM_CNT value computed as min(N, the largest VM_CNT value).
expcnt_sat(<N>) EXP_CNT value computed as min(N, the largest EXP_CNT value).
lgkmcnt_sat(<N>) LGKM_CNT value computed as min(N, the largest LGKM_CNT value).

These helpers may be specified in any order. Ampersands and commas may be used as optional separators.

N is either an :ref:`integer number<amdgpu_synid_integer_number>` or an :ref:`absolute expression<amdgpu_synid_absolute_expression>`.

Examples:

s_waitcnt 0
s_waitcnt vmcnt(1)
s_waitcnt expcnt(2) lgkmcnt(3)
s_waitcnt vmcnt(1) expcnt(2) lgkmcnt(3)
s_waitcnt vmcnt(1), expcnt(2), lgkmcnt(3)
s_waitcnt vmcnt(1) & lgkmcnt_sat(100) & expcnt(2)