1*12b1df16SDavid du Colombier/* 2*12b1df16SDavid du Colombier * R4000 user-level atomic operations 3*12b1df16SDavid du Colombier */ 4*12b1df16SDavid du Colombier 5*12b1df16SDavid du Colombier#define LL(base, rt) WORD $((060<<26)|((base)<<21)|((rt)<<16)) 6*12b1df16SDavid du Colombier#define SC(base, rt) WORD $((070<<26)|((base)<<21)|((rt)<<16)) 7*12b1df16SDavid du Colombier#define NOOP WORD $0x27 8*12b1df16SDavid du Colombier 9*12b1df16SDavid du ColombierTEXT ainc(SB), 1, $-4 /* long ainc(long *); */ 10*12b1df16SDavid du ColombierTEXT _xinc(SB), 1, $-4 /* void _xinc(long *); */ 11*12b1df16SDavid du Colombier MOVW R1, R2 /* address of counter */ 12*12b1df16SDavid du Colombierloop: MOVW $1, R3 13*12b1df16SDavid du Colombier LL(2, 1) 14*12b1df16SDavid du Colombier NOOP 15*12b1df16SDavid du Colombier ADDU R1, R3 16*12b1df16SDavid du Colombier MOVW R3, R1 /* return new value */ 17*12b1df16SDavid du Colombier SC(2, 3) 18*12b1df16SDavid du Colombier NOOP 19*12b1df16SDavid du Colombier BEQ R3,loop 20*12b1df16SDavid du Colombier RET 21*12b1df16SDavid du Colombier 22*12b1df16SDavid du ColombierTEXT adec(SB), 1, $-4 /* long adec(long*); */ 23*12b1df16SDavid du ColombierTEXT _xdec(SB), 1, $-4 /* long _xdec(long *); */ 24*12b1df16SDavid du Colombier MOVW R1, R2 /* address of counter */ 25*12b1df16SDavid du Colombierloop1: MOVW $-1, R3 26*12b1df16SDavid du Colombier LL(2, 1) 27*12b1df16SDavid du Colombier NOOP 28*12b1df16SDavid du Colombier ADDU R1, R3 29*12b1df16SDavid du Colombier MOVW R3, R1 /* return new value */ 30*12b1df16SDavid du Colombier SC(2, 3) 31*12b1df16SDavid du Colombier NOOP 32*12b1df16SDavid du Colombier BEQ R3,loop1 33*12b1df16SDavid du Colombier RET 34*12b1df16SDavid du Colombier 35*12b1df16SDavid du Colombier/* 36*12b1df16SDavid du Colombier * int cas(uint* p, int ov, int nv); 37*12b1df16SDavid du Colombier */ 38*12b1df16SDavid du ColombierTEXT cas(SB), 1, $-4 39*12b1df16SDavid du Colombier MOVW ov+4(FP), R2 40*12b1df16SDavid du Colombier MOVW nv+8(FP), R3 41*12b1df16SDavid du Colombierspincas: 42*12b1df16SDavid du Colombier LL(1, 4) /* R4 = *R1 */ 43*12b1df16SDavid du Colombier NOOP 44*12b1df16SDavid du Colombier BNE R2, R4, fail 45*12b1df16SDavid du Colombier SC(1, 3) /* *R1 = R3 */ 46*12b1df16SDavid du Colombier NOOP 47*12b1df16SDavid du Colombier BEQ R3, spincas /* R3 == 0 means store failed */ 48*12b1df16SDavid du Colombier MOVW $1, R1 49*12b1df16SDavid du Colombier RET 50*12b1df16SDavid du Colombierfail: 51*12b1df16SDavid du Colombier MOVW $0, R1 52*12b1df16SDavid du Colombier RET 53