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// 计算结果，有进位借位或溢出或溢出产生，则为非0，否则为0

// 调用完宏后直接加以判断

int g_iResult = 0;

// 对有符号整数数学计算进行判断

#define CARRY \

__asm__ ("jo <chmetcnv unitname="F" sourcevalue="0" hasspace="False" negative="False" numbertype="1" tcsc="0" w:st="on">0f</chmetcnv>\n\t" \

"movl $0, g_iResult\n\t" \

"jmp <chmetcnv unitname="F" sourcevalue="1" hasspace="False" negative="False" numbertype="1" tcsc="0" w:st="on">1f</chmetcnv>\n\t" \

"0:\n\t" \

"movl $1, g_iResult\n\t" \

"1:\n\t");

// 对无符号整数数学计算进行判断

#define OVER_FLOW \

__asm__ ("jc <chmetcnv unitname="F" sourcevalue="0" hasspace="False" negative="False" numbertype="1" tcsc="0" w:st="on">0f</chmetcnv>\n\t" \

"movl $0, g_iResult\n\t" \

"jmp <chmetcnv unitname="F" sourcevalue="1" hasspace="False" negative="False" numbertype="1" tcsc="0" w:st="on">1f</chmetcnv>\n\t" \

"0:\n\t" \

"movl $1, g_iResult\n\t" \

"1:\n\t");

对于数学计算是无符号还是有符号，和参与计算的整型变量本身没有关系，而是视程序把计算结果当成有符号还是无符号而定。汇编代码为AT&T语法格式。

——元创，于<chsdate w:st="on" year="2007" month="10" day="14" islunardate="False" isrocdate="False"><span lang="EN-US" style="FONT-SIZE: 12pt; LINE-HEIGHT: 150%">2007</span><span style="FONT-SIZE: 12pt; LINE-HEIGHT: 150%; FONT-FAMILY: 宋体">年</span><span lang="EN-US" style="FONT-SIZE: 12pt; LINE-HEIGHT: 150%">10</span><span style="FONT-SIZE: 12pt; LINE-HEIGHT: 150%; FONT-FAMILY: 宋体">月</span><span lang="EN-US" style="FONT-SIZE: 12pt; LINE-HEIGHT: 150%">14</span><span style="FONT-SIZE: 12pt; LINE-HEIGHT: 150%; FONT-FAMILY: 宋体">日</span></chsdate>