ref: bd773dee09460f5d77c96f2fe3d34ec5ee0b54ce dir: /sys/src/9/sgi/init9.s/
TEXT _main(SB), $8 MOVW $setR30(SB), R30 MOVW $boot(SB), R1 ADDU $12, R29, R2 /* get a pointer to 0(FP) */ MOVW R1, 4(R29) MOVW R2, 8(R29) JAL startboot(SB)