STM32G474--Whetstone程序移植(单精度)笔记

1 准备基本工程代码

参考这篇笔记从我的仓库中选择合适的基本工程，进行程序移植。这里我用的是stm32g474的基本工程。
使用git clone一个指定文件或者目录

2 移植程序

2.1 修改Whetstone.c

主要修改原本变量定义的类型，以及函数接口全部更换为单精度类型。其次在计时方式上这里使用的是DWT的方式计时，比TM32G474–Whetstone程序移植(双精度)笔记的计时方式更好一些，但需要更加注意溢出的问题。

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>

// 添加头文件
#include "main.h"
#include <stdint.h>
#include "stm32g4xx_hal.h"//stm32G4的hal库头文件，若更换芯片型哈需要更改
#include "debug_PmuDwt.h"

/* map the FORTRAN math functions, etc. to the C versions */
#define DSIN    sinf
#define DCOS    cosf
#define DATAN   atanf
#define DLOG    logf
#define DEXP    expf
#define DSQRT   sqrtf
#define IF      if

/* function prototypes */
void POUT(long N, long J, long K, float X1, float X2, float X3, float X4);
void PA(float E[]);
void P0(void);
void P3(float X, float Y, float *Z);
#define USAGE   "usage: whetdc [-c] [loops]\n"

//#define PRINTOUT 1

float time_in_secs(uint64_t ticks);

/*
    COMMON T,T1,T2,E1(4),J,K,L
*/
float T,T1,T2,E1[5];
int J,K,L;
int argc = 0;   //Mod for nucleo. Change in code below if you want non-default loop count

//************************************
//**    Whetstone    64b-DP         **
//**        SUB                     **
//************************************
int Whetstone(void) // ------------ Metoda -----------
{
    printf("Beginning Whetstone benchmark at ");
    
    printf(" %d MHz ...\n\n", SystemCoreClock/1000000);
    /* used in the FORTRAN version */
    long I;
    long N1, N2, N3, N4, N6, N7, N8, N9, N10, N11;
    float X1,X2,X3,X4,X,Y,Z;
    long LOOP;
    int II, JJ;

    /* added for this version */
    long loopstart = 0;
    uint64_t startsec,finisec = 0;
    uint32_t delta=0;
    float KIPS;
    int continuous;

    loopstart = 40000;       /* 1000 see the note about LOOP below */
    continuous = 0;

    II = 1;     /* start at the first arg (temp use of II here) */
 
LCONT:
/*
********************************************
*   Start benchmark timing at this point.
********************************************
*/
    startsec = 0;
    finisec = 0;
    
    delta = PMU_DWT_CounterCalibrate();
    
    startsec = PMU_DWT_CounterGet();

/*
********************************************
*   The actual benchmark starts here.
********************************************
*/
    T  = .499975f;
    T1 = 0.50025f;
    T2 = 2.0f;
/*
********************************************
*   With loopcount LOOP=10, one million Whetstone instructions
*   will be executed in EACH MAJOR LOOP..A MAJOR LOOP IS EXECUTED
*   'II' TIMES TO INCREASE WALL-CLOCK TIMING ACCURACY.
*
*   LOOP = 1000;
*/
    LOOP = loopstart;
    II   = 1;
    JJ = 1;

IILOOP:
    N1  = 0;
    N2  = 12 * LOOP;
    N3  = 14 * LOOP;
    N4  = 345 * LOOP;
    N6  = 210 * LOOP;
    N7  = 32 * LOOP;
    N8  = 899 * LOOP;
    N9  = 616 * LOOP;
    N10 = 0;
    N11 = 93 * LOOP;
/*
********************************************
*   Module 1: Simple identifiers
********************************************
*/
    X1  =  1.0f;
    X2  = -1.0f;
    X3  = -1.0f;
    X4  = -1.0f;

    for (I = 1; I <= N1; I++)
    {
        X1 = (X1 + X2 + X3 - X4) * T;
        X2 = (X1 + X2 - X3 + X4) * T;
        X3 = (X1 - X2 + X3 + X4) * T;
        X4 = (-X1+ X2 + X3 + X4) * T;
    }
#ifdef PRINTOUT
    IF (JJ==II) POUT(N1,N1,N1,X1,X2,X3,X4);
#endif

/*
********************************************
*   Module 2: Array elements
********************************************
*/
    E1[1] =  1.0f;
    E1[2] = -1.0f;
    E1[3] = -1.0f;
    E1[4] = -1.0f;

    for (I = 1; I <= N2; I++)
    {
        E1[1] = ( E1[1] + E1[2] + E1[3] - E1[4]) * T;
        E1[2] = ( E1[1] + E1[2] - E1[3] + E1[4]) * T;
        E1[3] = ( E1[1] - E1[2] + E1[3] + E1[4]) * T;
        E1[4] = (-E1[1] + E1[2] + E1[3] + E1[4]) * T;
    }

#ifdef PRINTOUT
    IF (JJ==II) POUT(N2,N3,N2,E1[1],E1[2],E1[3],E1[4]);
#endif

/*
********************************************
*  Module 3: Array as parameter
********************************************
*/
    for (I = 1; I <= N3; I++)
    {
        PA(E1);
    }
#ifdef PRINTOUT
    IF (JJ==II) POUT(N3,N2,N2,E1[1],E1[2],E1[3],E1[4]);
#endif

/*
********************************************
*   Module 4: Conditional jumps
********************************************
*/
    J = 1;
    for (I = 1; I <= N4; I++)
    {
        if (J == 1)
            J = 2;
        else
            J = 3;

        if (J > 2)
            J = 0;
        else
            J = 1;

        if (J < 1)
            J = 1;
        else
            J = 0;
    }

#ifdef PRINTOUT
    IF (JJ==II) POUT(N4,J,J,X1,X2,X3,X4);
#endif

/*
********************************************
*   Module 5: Omitted
*   Module 6: Integer arithmetic
********************************************
*/

    J = 1;
    K = 2;
    L = 3;

    for (I = 1; I <= N6; I++)
    {
        J = J * (K-J) * (L-K);
        K = L * K - (L-J) * K;
        L = (L-K) * (K+J);
        E1[L-1] = J + K + L;
        E1[K-1] = J * K * L;
    }

#ifdef PRINTOUT
    IF (JJ==II) POUT(N6,J,K,E1[1],E1[2],E1[3],E1[4]);
#endif

/*
********************************************
*   Module 7: Trigonometric functions
********************************************
*/
    X = 0.5f;
    Y = 0.5f;

    for (I = 1; I <= N7; I++)
    {
        X = T * DATAN(T2*DSIN(X)*DCOS(X)/(DCOS(X+Y)+DCOS(X-Y)-1.0f));
        Y = T * DATAN(T2*DSIN(Y)*DCOS(Y)/(DCOS(X+Y)+DCOS(X-Y)-1.0f));
    }

#ifdef PRINTOUT
    IF (JJ==II)POUT(N7,J,K,X,X,Y,Y);
#endif

/*
********************************************
*   Module 8: Procedure calls
********************************************
*/
    X = 1.0;
    Y = 1.0;
    Z = 1.0;

    for (I = 1; I <= N8; I++)
    {
        P3(X,Y,&Z);
    }
#ifdef PRINTOUT
    IF (JJ==II)POUT(N8,J,K,X,Y,Z,Z);
#endif

/*
********************************************
*   Module 9: Array references
********************************************
*/
    J = 1;
    K = 2;
    L = 3;
    E1[1] = 1.0;
    E1[2] = 2.0;
    E1[3] = 3.0;

    for (I = 1; I <= N9; I++)
    {
        P0();
    }
#ifdef PRINTOUT
    IF (JJ==II) POUT(N9,J,K,E1[1],E1[2],E1[3],E1[4]);
#endif

/*
********************************************
*   Module 10: Integer arithmetic
********************************************
*/
    J = 2;
    K = 3;

    for (I = 1; I <= N10; I++)
    {
        J = J + K;
        K = J + K;
        J = K - J;
        K = K - J - J;
    }

#ifdef PRINTOUT
    IF (JJ==II) POUT(N10,J,K,X1,X2,X3,X4);
#endif

/*
********************************************
*   Module 11: Standard functions
********************************************
*/
    X = 0.75;

    for (I = 1; I <= N11; I++)
    {
        X = DSQRT(DEXP(DLOG(X)/T1));
    }
#ifdef PRINTOUT
    IF (JJ==II) POUT(N11,J,K,X,X,X,X);
#endif

/*
********************************************
*      THIS IS THE END OF THE MAJOR LOOP.
********************************************
*/
    if (++JJ <= II)
        goto IILOOP;

/*
********************************************
*      Stop benchmark timing at this point.
********************************************
*/
   // finisec = time(0);
    finisec = PMU_DWT_CounterGet();
    //timer.reset();

/*
*--------------------------------------------------------------------
*      Performance in Whetstone KIP's per second is given by
*
*   (100*LOOP*II)/TIME
*
*      where TIME is in seconds.
*--------------------------------------------------------------------
*/
    float vreme;
    vreme = time_in_secs(finisec - startsec - delta);
    
    if (vreme <= 0)
     {
        printf("Insufficient duration- Increase the LOOP count \n");
        finisec = 0; 
        startsec = 0;
        return 1;
     }

    printf("Loops: %ld , \t Iterations: %d, \t Duration: %.3f sec. \n",
            LOOP, II, vreme);

    KIPS = (100.0f * LOOP * II) / vreme ;
   
    if (KIPS >= 1000.0f)
        printf("C Converted Float Precision Whetstones: %.3f MIPS \n\n", KIPS / 1000);
    else
        printf("C Converted Float Precision Whetstones: %.3f KIPS \n\n", KIPS);

    if (continuous)
        goto LCONT;

    finisec = 0; 
    startsec = 0;
    return 1;
}

void PA(float E[])
{
    J = 0;

L10:
    E[1] = ( E[1] + E[2] + E[3] - E[4]) * T;
    E[2] = ( E[1] + E[2] - E[3] + E[4]) * T;
    E[3] = ( E[1] - E[2] + E[3] + E[4]) * T;
    E[4] = (-E[1] + E[2] + E[3] + E[4]) / T2;
    J += 1;

    if (J < 6)
        goto L10;
}

void P0(void)
{
    E1[J] = E1[K];
    E1[K] = E1[L];
    E1[L] = E1[J];
}

void P3(float X, float Y, float *Z)
{
    float X1, Y1;

    X1 = X;
    Y1 = Y;
    X1 = T * (X1 + Y1);
    Y1 = T * (X1 + Y1);
    *Z  = (X1 + Y1) / T2;
}

float time_in_secs(uint64_t ticks)
{
  // scale timer down to avoid uint64_t -> double conversion in RV32
  uint32_t scale = 170000000;
  float delta = (float)(ticks*(1.0f)) / scale;
  return delta;
}


#ifdef PRINTOUT
void POUT(long N, long J, long K, float X1, float X2, float X3, float X4)
{
    printf("%7ld %7ld %7ld %12.4e %12.4e %12.4e %12.4e\n",
                        N, J, K, X1, X2, X3, X4);
}
#endif

2.2 修改main.c

删除示例工程中测试基本功能的一小段函数，将以下这段函数放置在while前执行即可。

  printf("\nMy Benchmark example for Whetstones \n");
  printf("Whetstone ");
  
  PMU_DWT_Initialize();// 初始化DWT
  
  Whetstone();// 测试函数

2.3 修改main.h

和双精度的示例相同，需要添加测试函数的声明。

int Whetstone(void);

3 测试结果

暂时没有具体分析细节问题，只是跑通了