ref: 8a45afd47d2545b2d85aecf9ec5af90cba3905d3
dir: /sys/src/libc/mips/tas.s/
/* * magnum 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 #define COP3 WORD $(023<<26) TEXT C_3ktas(SB),$0 MOVW R1, R21 btas: MOVW R21, R1 MOVB R0, 1(R1) NOOP COP3 BLTZ R1, btas RET TEXT C_4ktas(SB), $0 MOVW R1, R2 /* address of key */ tas1: MOVW $1, R3 LL(2, 1) NOOP SC(2, 3) NOOP BEQ R3, tas1 RET TEXT C_fcr0(SB), $0 MOVW FCR0, R1 RET