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There is sometimes need to get the parity of a 32-bit word. This is one solution:;
; get parity of 32 bit word
;
; input:
; eax = word to get parity from
;
; output:
; flags (parity flag)
;
; destroys:
; eax,ebx
;
mov ebx,eax
shr eax,16
xor eax,ebx
xor al,ah
jp Parity ; 4 cycles if correctly predictedFor 16-bit code SHLD (4 cycles?) seems to be equivalent to MOV (2) + SHR (2), and better on 386/486 cpus:;
; get parity of 32 bit word
;
; input:
; eax = word to get parity from
;
; output:
; flags (parity flag)
;
; destroys:
; eax,ebx
;
shld ebx,eax,16
xor ax,bx
xor al,ah
jp Parity ; 6 cycles in 16-bit mode?