🚀 go-pugleaf

>>>>> On 30 Sep 92 18:00:46 GMT, bright@nazgul.UUCP (Walter Bright) said:

Walter> I have heard that there is a "well-known trick" for evaluating
Walter> 	(a > b) ? a : b
Walter> in assembler language without using any jump instructions. I haven't
Walter> been able to discover what that trick is. Does anyone know?

Probably something like: mov r1,a / mov r2,b / sub r2,r1 / cmc
sbb r3,r3 / and r3,r2 / add r3,r1 / mov result,r3
The SUB sets CF when a>b, CMC complements the CF, after the SBB
if a>b r3 is 0 (and then AND gives 0, ADD gives r1=a), otherwise
r3 is 0xFFFF (and then AND gives b-a, ADD gives b).
This all for unsigned arithmetic only... Jerzy Tarasiuk