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diff --git a/db2/mutex/uts4_cc.s b/db2/mutex/uts4_cc.s
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+ /
+ / int uts_lock ( int *p, int i );
+ / Update the lock word pointed to by p with the
+ / value i, using compare-and-swap.
+ / Returns 0 if update was successful.
+ / Returns 1 if update failed.
+ /
+ entry uts_lock
+ uts_lock:
+ using .,r15
+ st r2,8(sp) / Save R2
+ l r2,64+0(sp) / R2 -> word to update
+ slr r0, r0 / R0 = current lock value must be 0
+ l r1,64+4(sp) / R1 = new lock value
+ cs r0,r1,0(r2) / Try the update ...
+ be x / ... Success. Return 0
+ la r0,1 / ... Failure. Return 1
+ x: /
+ l r2,8(sp) / Restore R2
+ b 2(,r14) / Return to caller
+ drop r15