如何获得“每行代码的执行时间"?为我的程序? [英] How to get "execution time for each line of code" for my program?

问题描述

我只是用gprof分析我的程序.我想看看哪些功能消耗了最多的CPU时间.
但是，现在我想以另一种方式分析我的程序.我想看看哪些代码行占用最多的CPU时间.
起初，我读到gprof可以做到，但是我找不到适合的选项.
现在，我找到了gcov.但是，我尝试执行的第三方程序没有"./configure".因此我无法应用"./configure --enable-gcov".

我的问题很简单.有谁知道如何为我的程序的每一行代码获取执行时间?
(我更喜欢gprof的建议，因为我发现它的输出非常易于阅读和理解.)

问候，
Linux noob

Hi,
I just used gprof to analyze my program. I wanted to see what functions were consuming the most CPU time.
However, now I would like to analyze my program in a different way. I want to see what LINES of the code that consume the most CPU time.
At first, I read that gprof could do that, but I couldn''t find the right option for it.
Now, I found gcov. However, the third-party program I am trying to execute has no "./configure" so I could not apply the "./configure --enable-gcov".

My question is simple. Does anyone know how to get execution time for each line of code for my program?
(I prefer suggestions with gprof, because I found its output to be very easy to read and understand.)

Regards,
Linux noob

推荐答案

问题是编译器不关心在源代码中放置换行符的位置.它会看到您的代码包含声明 [基本块 [ ^ ]，而不是一行. 每行的执行时间"的整个想法几乎毫无意义.

The problem is that the compiler doesn''t care about where you put line feeds in your source code. It sees your code consisting of statements[^] and basic blocks[^], not lines. The whole idea of "execution time of each line" is nearly meaningless.

请考虑以下代码:

Please consider this code :

#include 
#include <stdio.h>
#include <unistd.h>
int main()
{
    struct timeval start, end;

    long mtime, seconds, useconds;    

    gettimeofday(&start, NULL);
    ProfiledFunction();
    gettimeofday(&end, NULL);

    seconds  = end.tv_sec  - start.tv_sec;
    useconds = end.tv_usec - start.tv_usec;

    mtime = ((seconds) * 1000 + useconds/1000.0) + 0.5;

    printf("Elapsed time: %ld milliseconds\n", mtime);

    return 0;
}

</unistd.h></stdio.h>

ProfiledFunction是正在分析的功能.
代码是从这里提取的:
http://stackoverflow.com/Questions/588307/c-obtaining-milliseconds-time-on-linux-clock-doesnt-seem-to-work-properl [ http://kerneltrap.org/node/6393 [

ProfiledFunction is the function which is being profiled.
The code was extracted from here :
http://stackoverflow.com/questions/588307/c-obtaining-milliseconds-time-on-linux-clock-doesnt-seem-to-work-properl[^]


If you need microsecond precision just use tv_usec part of timeval structure.

If you''re developing in kernel mode please consider using this function :
http://kerneltrap.org/node/6393[^]


Hope it helps.

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