#defineunlikely(x) __builtin_expect(!!(x), 0) __builtin_expect是编译器内建函数,原型为long __builtin_expect (long exp, long c)。 a>100不太可能发生写法 intfun(inta) { if(unlikely(a>100)) ... } 1.likely和unlikely使用判断必须准确,写反会使运行速度变慢。 2.编译时优化一般需要至少...
在这个过程中,gcc编译器帮我们把likely.c的分支代码逻辑,翻译成了cmpl、je、addl、jmp和subl等汇编机器指令给CPU去执行。 3、CPU Cache和指令预取 上面的likely.c源码,经过编译,最终生成了likely可执行程序,这个可执行程序现在在磁盘上,当我们在linux系统上通过./likely执行程序时,计算机会把likely程序文件包含的内...
During field trials of the two known cerambycid beetle pheromone components 3-hydroxyhexan-2-one and 1-(1 H -pyrrol-2-yl)-1,2-propanedione (henceforth "pyrrole") in Guangxi and Anhui provinces in China, four species in the subfamily Cerambycinae were attracted to lures containing one of ...
Information on (changes in) standing and lying behaviour of cows can be used for oestrus detection, early diagnosis of disorders and to evaluate welfare consequences of changes in housing and management. Data sets on lying and standing behaviour were collected from cows with IceTag sensors fitted ...
在linux内核源码或一些比较成熟的c语言架构源码中,我们常会见到类似下面的代码: 复制代码 1if(unlikely(!packet)) {2returnres_failed;3}45//OR67if(likely(packet->type =HTTP)) {8do_something();9} 有的地方可能会用大写,LIKELY() / UNLIKELY(),意思一样。
To get a broad idea of what a study participant's family environment was like during their childhood, participants answered survey questions such as how often a parent or other adult in the household made the participant feel loved, supported and cared for, and how often a parent or other...
(c) seem likely that + 子句 看來可能……;看似可能…… Itseems likely thatthe epidemic in the UK would only get worse. 英國的疫情可能只會越來越嚴重。 補充:That’s a likely story. Likely 作為形容詞「可能的」加上 story. 直翻為「有可能性的故事」,亦即表示某件事「聽起來像真的一樣」,也...
WASHINGTON , Jan . 28 ( Xinhua ) - - By the age of six , girls become less likely than boys to believe that members of their gender are brilliant , and are more likely to avoid activities said to be for children who are
A. probably B.possibly C.likely D.perhaps 点拨不能说It is perhaps to …;A, B都是副词，所以不能选择 A或B。常不用 It is probable to do sth.但可以说It is possible that从句.请看以下例句：It is possible for him to finish work.It is possible that he shall finish work.I...
Furthermore, the vector adjustment was able to recover 95% of the actual positional displacement present in the database. To demonstrate a practical ... C Bray - ISPRS International Journal of Geo-Information 被引量: 0发表: 2007年 加载更多研究点推荐 Positional Play Data 站内活动 0关于...