Re: [理工] 計組

[wheels ()]

※ 引述《Byzantin (拜占庭)》之銘言：
: Suppose that all of conditional branch instructions except
: beq and bne were removed from MIPS instruction set along with
: slt and all of its variants.
: Show how to perform
: slt $t0,$s0,$s1

我的答案，再改一次XD

可以參考一下:)

        sub  $t3, $s0, $s1

        sll  $t4, $t3, 1

        srl  $t4, $t4, 1

        xor  $t2, $t3, t4

        add  $t0, $zero, $zero

        beq  $t2, $zero, NOT_SET

        addi $t0, $t0, 1

NOT_SET:add  $t0, $t0, $zero

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◆ From: 140.112.30.141
※ 編輯: wheels          來自: 140.112.30.141       (01/31 17:11)
→ wheels:推文的比較好。
→ metalalive:請教先 sll再srl的理由是? 3q @O@
→ wheels:為了讓MSB變0，MSB以外的位置不變，所以XOR完必定是0。
→ wheels:這樣可以抓出相減完的sign。