Plan 9 from Bell Labs’s /usr/web/sources/contrib/quanstro/root/sys/src/cmd/aux/cpuid/amd64.s
TEXT cpuid1(SB), 1, $0 MOVQ RARG, BP MOVL 0(BP), AX MOVL 4(BP), BX MOVL 8(BP), CX MOVL 12(BP), DX CPUID MOVQ RARG, BP MOVL AX, 0(BP) MOVL BX, 4(BP) MOVL CX, 8(BP) MOVL DX, 12(BP) RET