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用的是创龙的OMAP-L138的板子和XDS100v3仿真器,用的方法是TSCL = 0;
+ t I. Y- Q: z7 y* Y TSCH = 0;
1 ~. `% d# K$ x$ A, k3 q7 p6 t unsigned long long start,stop,overhead;
( k, e. f/ D( e start = _itoll(TSCH,TSCL);
$ I% P6 ]( o" B# l. I- u stop = _itoll(TSCH,TSCL);
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& _* M/ Q* Z' Moverhead = stop - start;) e3 ]) k8 o' y- x6 b/ C
printf("overhead run-time is %d\n",overhead);% W& @! c! K, m/ w- u
! L) o9 b# w$ dstart = _itoll(TSCH,TSCL);
+ Y$ n6 t9 R" R7 g//here is function! _: R3 e7 N* N6 L7 o" O
function();' J6 ]; {1 S9 Y; v( q* A; I
stop = _itoll(TSCH,TSCL);6 ~6 N1 \0 T/ `
printf("The function run-time time is %lu\n",(stop - start - overhead));
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为什么每次测量出来的时间都不一致?测量出来的不是一个固定的值。8 X6 B0 C( ?5 _: N1 U3 ]" Y' J
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