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/*
Copyright (c) 2010-2023, Intel Corporation
SPDX-License-Identifier: BSD-3-Clause
*/
#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS
#define NOMINMAX
#pragma warning(disable : 4244)
#pragma warning(disable : 4305)
#endif
#include "../../common/timing.h"
#include "mandelbrot_ispc.h"
#include <algorithm>
#include <cstdlib>
#include <stdio.h>
#include <string.h>
using namespace ispc;
extern void mandelbrot_serial(float x0, float y0, float x1, float y1, int width, int height, int maxIterations,
int output[]);
/* Write a PPM image file with the image of the Mandelbrot set */
static void writePPM(int *buf, int width, int height, const char *fn) {
FILE *fp = fopen(fn, "wb");
if (!fp) {
printf("Couldn't open a file '%s'\n", fn);
exit(-1);
}
fprintf(fp, "P6\n");
fprintf(fp, "%d %d\n", width, height);
fprintf(fp, "255\n");
for (int i = 0; i < width * height; ++i) {
// Map the iteration count to colors by just alternating between
// two greys.
char c = (buf[i] & 0x1) ? (char)240 : 20;
for (int j = 0; j < 3; ++j)
fputc(c, fp);
}
fclose(fp);
printf("Wrote image file %s\n", fn);
}
int main(int argc, char *argv[]) {
static unsigned int test_iterations[] = {3, 3};
unsigned int width = 768;
unsigned int height = 512;
float x0 = -2;
float x1 = 1;
float y0 = -1;
float y1 = 1;
if (argc > 1) {
if (strncmp(argv[1], "--scale=", 8) == 0) {
float scale = atof(argv[1] + 8);
width *= scale;
height *= scale;
}
}
if ((argc == 3) || (argc == 4)) {
for (int i = 0; i < 2; i++) {
test_iterations[i] = atoi(argv[argc - 2 + i]);
}
}
int maxIterations = 256;
int *buf = new int[width * height];
//
// Compute the image using the ispc implementation; report the minimum
// time of three runs.
//
double minISPC = 1e30;
for (unsigned int i = 0; i < test_iterations[0]; ++i) {
reset_and_start_timer();
mandelbrot_ispc(x0, y0, x1, y1, width, height, maxIterations, buf);
double dt = get_elapsed_mcycles();
printf("@time of ISPC run:\t\t\t[%.3f] million cycles\n", dt);
minISPC = std::min(minISPC, dt);
}
printf("[mandelbrot ispc]:\t\t[%.3f] million cycles\n", minISPC);
writePPM(buf, width, height, "mandelbrot-ispc.ppm");
// Clear out the buffer
for (unsigned int i = 0; i < width * height; ++i)
buf[i] = 0;
//
// And run the serial implementation 3 times, again reporting the
// minimum time.
//
double minSerial = 1e30;
for (unsigned int i = 0; i < test_iterations[1]; ++i) {
reset_and_start_timer();
mandelbrot_serial(x0, y0, x1, y1, width, height, maxIterations, buf);
double dt = get_elapsed_mcycles();
printf("@time of serial run:\t\t\t[%.3f] million cycles\n", dt);
minSerial = std::min(minSerial, dt);
}
printf("[mandelbrot serial]:\t\t[%.3f] million cycles\n", minSerial);
writePPM(buf, width, height, "mandelbrot-serial.ppm");
printf("\t\t\t\t(%.2fx speedup from ISPC)\n", minSerial / minISPC);
return 0;
}
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