ref: aa40fda4e41feafd05bf777a969aa2b4b6c7f070 dir: /mbld/cpufeatures+plan9-x64.s/
TEXT bld$cpufeatures+0(SB),$0 MOVL $0x1,AX CPUID MOVL CX, AX MOVL DX, DX ROLQ $32, DX ORQ DX, AX RET