我用STM32F301做实验，就计算浮点数的加减乘除，为什么启用FPU反而比不启用FPU计算慢？。下面是我实验的代码，很简单。通过观察小灯的闪烁快慢来看计算速度。
#include "LED.h"
#include "system_tick.h"
#include "math.h"
//#include "arm_math.h"
int i=0;
float c=1.3f,sin_vlu=0.0f,cos_vlu=0.0f;
int main(void)
{
SystemTick_init();
LED_Init();
while(1)
{
LED0_ON;
/*************************FPU运算************************/
for(i=0;i<65536;i++)
{
// arm_sin_cos_f32(30.0f,&sin_vlu,&cos_vlu);
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
}
///*************************CPU运算**************************/
// for(i=0;i<65536;i++)
// {
// c = cos(1.3f);
// }
LED0_OFF;
/*************************FPU运算************************/
for(i=0;i<65536;i++)
{
// arm_sin_cos_f32(30.0f,&sin_vlu,&cos_vlu);
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
}
///*************************CPU运算**************************/
// for(i=0;i<65536;i++)
// {
// c = cos(1.3f);
// }
}
}
友情提示: 此问题已得到解决，问题已经关闭,关闭后问题禁止继续编辑，回答。
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你不用FPU时用的是 for(i=0;i<65536;i++)
// {
// c = cos(1.3f);
// }
用FPU时，用的是 c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f*2.5623f/3.00543f+6.00435f-4.56234f;
c=3.1f*2.5623f/3.00543f+6
这两种公式都不一样。能放到一起比吗？
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