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/*
* R4000 user level lock code
*/
#define LL(base, rt) WORD $((060<<26)|((base)<<21)|((rt)<<16))
#define SC(base, rt) WORD $((070<<26)|((base)<<21)|((rt)<<16))
#define NOOP WORD $0x27
#ifdef oldstyle
TEXT xadd(SB), $0
MOVW R1, R2 /* address of counter */
loop: MOVW n+4(FP), R3 /* increment */
LL(2, 1)
NOOP
ADD R1,R3,R3
SC(2, 3)
NOOP
BEQ R3,loop
RET
#endif
TEXT _xinc(SB), $0
MOVW R1, R2 /* address of counter */
loop: MOVW $1, R3
LL(2, 1)
NOOP
ADD R1,R3,R3
SC(2, 3)
NOOP
BEQ R3,loop
RET
TEXT _xdec(SB), $0
MOVW R1, R2 /* address of counter */
loop1: MOVW $-1, R3
LL(2, 1)
NOOP
ADD R1,R3,R3
MOVW R3, R1
SC(2, 3)
NOOP
BEQ R3,loop1
RET
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