#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int main(int argc, char *argv[]){
char a[5];
char b[10];
strcpy(a,"nop");
gets(b);
printf("Hello there %s. Value in a is %s.\n",b,a);
exit(0);
}
前几条生产线的装配输出显示:
push %ebp
mov %esp,%ebp
sub $0x
我有以下类型的代码
short v[8] __attribute__ (( aligned(16)));
...
// in an inlined function :
_mm_store_si128(v, some_m128i_value);
... // some more operation (4 additions )
outp[0] = v[1] / 2; // <- first access of v since the previous store
当我用perf注释这段代码时,这一行占整个采样的18%!当我说行的时候,它是在汇编级的,即从v转移后的指令占18%
这是缓存
为什么两个字符的UTF-16字符串在内存中只占6个字节,而一个字符的UTF-16字符串只占4个字节?
下面是java中的一个SSCCE来演示这种行为:
public class UTF16Test{
public static void main(String[] args) throws Exception {
System.out.println("A".getBytes("UTF-16").length);
System.out.println("AB".getBytes("UTF-16
- (IBaction)switchview6:(id)sender {
information *info = [[Information alloc] initWithNibName:nil bundle nil];
[self presentModalViewController:info animated:YES]; }
然后我得到了这个错误:
Potential leak of an object allocated on line 23 and stored into "info"
朋友们,我该怎么解决这个问题呢?你能准确地给我打一行吗?我读了很多