working on aobench

This commit is contained in:
Evghenii
2013-11-10 14:29:53 +01:00
parent 17809992d7
commit 66edc180be
4 changed files with 780 additions and 0 deletions

283
examples_cuda/aobench/ao.cu Normal file
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// -*- mode: c++ -*-
/*
Copyright (c) 2010-2011, Intel Corporation
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of Intel Corporation nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
Based on Syoyo Fujita's aobench: http://code.google.com/p/aobench
*/
#define NAO_SAMPLES 8
#define M_PI 3.1415926535f
typedef float<3> vec;
#ifdef __NVPTX__
#warning "emitting DEVICE code"
#define programCount warpSize()
#define programIndex laneIndex()
#define taskIndex blockIndex0()
#define taskCount blockCount0()
#else
#warning "emitting HOST code"
#endif
struct Isect {
float t;
vec p;
vec n;
int hit;
};
struct Sphere {
vec center;
float radius;
};
struct Plane {
vec p;
vec n;
};
struct Ray {
vec org;
vec dir;
};
static inline float dot(vec a, vec b) {
return a.x * b.x + a.y * b.y + a.z * b.z;
}
static inline vec vcross(vec v0, vec v1) {
vec ret;
ret.x = v0.y * v1.z - v0.z * v1.y;
ret.y = v0.z * v1.x - v0.x * v1.z;
ret.z = v0.x * v1.y - v0.y * v1.x;
return ret;
}
static inline void vnormalize(vec &v) {
float len2 = dot(v, v);
float invlen = rsqrt(len2);
v *= invlen;
}
static inline void
ray_plane_intersect(Isect &isect, Ray &ray, uniform Plane &plane) {
float d = -dot(plane.p, plane.n);
float v = dot(ray.dir, plane.n);
if (abs(v) < 1.0e-17)
return;
else {
float t = -(dot(ray.org, plane.n) + d) / v;
if ((t > 0.0) && (t < isect.t)) {
isect.t = t;
isect.hit = 1;
isect.p = ray.org + ray.dir * t;
isect.n = plane.n;
}
}
}
static inline void
ray_sphere_intersect(Isect &isect, Ray &ray, uniform Sphere &sphere) {
vec rs = ray.org - sphere.center;
float B = dot(rs, ray.dir);
float C = dot(rs, rs) - sphere.radius * sphere.radius;
float D = B * B - C;
if (D > 0.) {
float t = -B - sqrt(D);
if ((t > 0.0) && (t < isect.t)) {
isect.t = t;
isect.hit = 1;
isect.p = ray.org + t * ray.dir;
isect.n = isect.p - sphere.center;
vnormalize(isect.n);
}
}
}
static inline void
orthoBasis(vec basis[3], vec n) {
basis[2] = n;
basis[1].x = 0.0; basis[1].y = 0.0; basis[1].z = 0.0;
if ((n.x < 0.6) && (n.x > -0.6)) {
basis[1].x = 1.0;
} else if ((n.y < 0.6) && (n.y > -0.6)) {
basis[1].y = 1.0;
} else if ((n.z < 0.6) && (n.z > -0.6)) {
basis[1].z = 1.0;
} else {
basis[1].x = 1.0;
}
basis[0] = vcross(basis[1], basis[2]);
vnormalize(basis[0]);
basis[1] = vcross(basis[2], basis[0]);
vnormalize(basis[1]);
}
static inline float
ambient_occlusion(Isect &isect, uniform Plane &plane, uniform Sphere spheres[3],
RNGState &rngstate) {
float eps = 0.0001f;
vec p, n;
vec basis[3];
float occlusion = 0.0;
p = isect.p + eps * isect.n;
orthoBasis(basis, isect.n);
static const uniform int ntheta = NAO_SAMPLES;
static const uniform int nphi = NAO_SAMPLES;
for (uniform int j = 0; j < ntheta; j++) {
for (uniform int i = 0; i < nphi; i++) {
Ray ray;
Isect occIsect;
float theta = sqrt(frandom(&rngstate));
float phi = 2.0f * M_PI * frandom(&rngstate);
float x = cos(phi) * theta;
float y = sin(phi) * theta;
float z = sqrt(1.0 - theta * theta);
// local . global
float rx = x * basis[0].x + y * basis[1].x + z * basis[2].x;
float ry = x * basis[0].y + y * basis[1].y + z * basis[2].y;
float rz = x * basis[0].z + y * basis[1].z + z * basis[2].z;
ray.org = p;
ray.dir.x = rx;
ray.dir.y = ry;
ray.dir.z = rz;
occIsect.t = 1.0e+17;
occIsect.hit = 0;
for (uniform int snum = 0; snum < 3; ++snum)
ray_sphere_intersect(occIsect, ray, spheres[snum]);
ray_plane_intersect (occIsect, ray, plane);
if (occIsect.hit) occlusion += 1.0;
}
}
occlusion = (ntheta * nphi - occlusion) / (float)(ntheta * nphi);
return occlusion;
}
/* Compute the image for the scanlines from [y0,y1), for an overall image
of width w and height h.
*/
static inline void ao_scanlines(uniform int y0, uniform int y1, uniform int w,
uniform int h, uniform int nsubsamples,
uniform float image[]) {
static uniform Plane plane = { { 0.0f, -0.5f, 0.0f }, { 0.f, 1.f, 0.f } };
static uniform Sphere spheres[3] = {
{ { -2.0f, 0.0f, -3.5f }, 0.5f },
{ { -0.5f, 0.0f, -3.0f }, 0.5f },
{ { 1.0f, 0.0f, -2.2f }, 0.5f } };
RNGState rngstate;
seed_rng(&rngstate, programIndex + (y0 << (programIndex & 15)));
float invSamples = 1.f / nsubsamples;
foreach_tiled(y = y0 ... y1, x = 0 ... w,
u = 0 ... nsubsamples, v = 0 ... nsubsamples)
{
float du = (float)u * invSamples, dv = (float)v * invSamples;
// Figure out x,y pixel in NDC
float px = (x + du - (w / 2.0f)) / (w / 2.0f);
float py = -(y + dv - (h / 2.0f)) / (h / 2.0f);
float ret = 0.f;
Ray ray;
Isect isect;
ray.org = 0.f;
// Poor man's perspective projection
ray.dir.x = px;
ray.dir.y = py;
ray.dir.z = -1.0;
vnormalize(ray.dir);
isect.t = 1.0e+17;
isect.hit = 0;
for (uniform int snum = 0; snum < 3; ++snum)
ray_sphere_intersect(isect, ray, spheres[snum]);
ray_plane_intersect(isect, ray, plane);
// Note use of 'coherent' if statement; the set of rays we
// trace will often all hit or all miss the scene
if (isect.hit) {
ret = ambient_occlusion(isect, plane, spheres, rngstate);
ret *= invSamples * invSamples;
int offset = 3 * (y * w + x);
atomic_add_local(&image[offset], ret);
atomic_add_local(&image[offset+1], ret);
atomic_add_local(&image[offset+2], ret);
}
}
}
export void ao_ispc(uniform int w, uniform int h, uniform int nsubsamples,
uniform float image[]) {
ao_scanlines(0, h, w, h, nsubsamples, image);
}
static void task ao_task(uniform int width, uniform int height,
uniform int nsubsamples, uniform float image[]) {
ao_scanlines(taskIndex, taskIndex+1, width, height, nsubsamples, image);
}
export void ao_ispc_tasks(uniform int w, uniform int h, uniform int nsubsamples,
uniform float image[]) {
launch[h] ao_task(w, h, nsubsamples, image);
}

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typedef float<3> vec;
#ifdef __NVPTX__
#warning "emitting DEVICE code"
#define programCount warpSize()
#define programIndex laneIndex()
#define taskIndex blockIndex0()
#define taskCount blockCount0()
#else
#warning "emitting HOST code"
#endif
struct Isect {
float t;
vec p;

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// -*- mode: c++ -*-
/*
Copyright (c) 2010-2011, Intel Corporation
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of Intel Corporation nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
Based on Syoyo Fujita's aobench: http://code.google.com/p/aobench
*/
#define NAO_SAMPLES 8
#define M_PI 3.1415926535f
typedef float<3> vec;
#ifdef __NVPTX__
#warning "emitting DEVICE code"
#define programCount warpSize()
#define programIndex laneIndex()
#define taskIndex blockIndex0()
#define taskCount blockCount0()
#else
#warning "emitting HOST code"
#endif
struct Isect {
float t;
vec p;
vec n;
int hit;
};
struct Sphere {
vec center;
float radius;
};
struct Plane {
vec p;
vec n;
};
struct Ray {
vec org;
vec dir;
};
static inline float dot(vec a, vec b) {
return a.x * b.x + a.y * b.y + a.z * b.z;
}
static inline vec vcross(vec v0, vec v1) {
vec ret;
ret.x = v0.y * v1.z - v0.z * v1.y;
ret.y = v0.z * v1.x - v0.x * v1.z;
ret.z = v0.x * v1.y - v0.y * v1.x;
return ret;
}
static inline void vnormalize(vec &v) {
float len2 = dot(v, v);
float invlen = rsqrt(len2);
v *= invlen;
}
static inline void
ray_plane_intersect(Isect &isect, Ray &ray, uniform Plane &plane) {
float d = -dot(plane.p, plane.n);
float v = dot(ray.dir, plane.n);
if (abs(v) < 1.0e-17)
return;
else {
float t = -(dot(ray.org, plane.n) + d) / v;
if ((t > 0.0) && (t < isect.t)) {
isect.t = t;
isect.hit = 1;
isect.p = ray.org + ray.dir * t;
isect.n = plane.n;
}
}
}
static inline void
ray_sphere_intersect(Isect &isect, Ray &ray, uniform Sphere &sphere) {
vec rs = ray.org - sphere.center;
float B = dot(rs, ray.dir);
float C = dot(rs, rs) - sphere.radius * sphere.radius;
float D = B * B - C;
if (D > 0.) {
float t = -B - sqrt(D);
if ((t > 0.0) && (t < isect.t)) {
isect.t = t;
isect.hit = 1;
isect.p = ray.org + t * ray.dir;
isect.n = isect.p - sphere.center;
vnormalize(isect.n);
}
}
}
static inline void
orthoBasis(vec basis[3], vec n) {
basis[2] = n;
basis[1].x = 0.0; basis[1].y = 0.0; basis[1].z = 0.0;
if ((n.x < 0.6) && (n.x > -0.6)) {
basis[1].x = 1.0;
} else if ((n.y < 0.6) && (n.y > -0.6)) {
basis[1].y = 1.0;
} else if ((n.z < 0.6) && (n.z > -0.6)) {
basis[1].z = 1.0;
} else {
basis[1].x = 1.0;
}
basis[0] = vcross(basis[1], basis[2]);
vnormalize(basis[0]);
basis[1] = vcross(basis[2], basis[0]);
vnormalize(basis[1]);
}
static inline float
ambient_occlusion(Isect &isect, uniform Plane &plane, uniform Sphere spheres[3],
RNGState &rngstate) {
float eps = 0.0001f;
vec p, n;
vec basis[3];
float occlusion = 0.0;
p = isect.p + eps * isect.n;
orthoBasis(basis, isect.n);
static const uniform int ntheta = NAO_SAMPLES;
static const uniform int nphi = NAO_SAMPLES;
for (uniform int j = 0; j < ntheta; j++) {
for (uniform int i = 0; i < nphi; i++) {
Ray ray;
Isect occIsect;
float theta = sqrt(frandom(&rngstate));
float phi = 2.0f * M_PI * frandom(&rngstate);
float x = cos(phi) * theta;
float y = sin(phi) * theta;
float z = sqrt(1.0 - theta * theta);
// local . global
float rx = x * basis[0].x + y * basis[1].x + z * basis[2].x;
float ry = x * basis[0].y + y * basis[1].y + z * basis[2].y;
float rz = x * basis[0].z + y * basis[1].z + z * basis[2].z;
ray.org = p;
ray.dir.x = rx;
ray.dir.y = ry;
ray.dir.z = rz;
occIsect.t = 1.0e+17;
occIsect.hit = 0;
for (uniform int snum = 0; snum < 3; ++snum)
ray_sphere_intersect(occIsect, ray, spheres[snum]);
ray_plane_intersect (occIsect, ray, plane);
if (occIsect.hit) occlusion += 1.0;
}
}
occlusion = (ntheta * nphi - occlusion) / (float)(ntheta * nphi);
return occlusion;
}
/* Compute the image for the scanlines from [y0,y1), for an overall image
of width w and height h.
*/
static inline void ao_scanlines(uniform int y0, uniform int y1, uniform int w,
uniform int h, uniform int nsubsamples,
uniform float image[]) {
static uniform Plane plane = { { 0.0f, -0.5f, 0.0f }, { 0.f, 1.f, 0.f } };
static uniform Sphere spheres[3] = {
{ { -2.0f, 0.0f, -3.5f }, 0.5f },
{ { -0.5f, 0.0f, -3.0f }, 0.5f },
{ { 1.0f, 0.0f, -2.2f }, 0.5f } };
RNGState rngstate;
seed_rng(&rngstate, programIndex + (y0 << (programIndex & 15)));
float invSamples = 1.f / nsubsamples;
foreach_tiled(y = y0 ... y1, x = 0 ... w,
u = 0 ... nsubsamples, v = 0 ... nsubsamples)
{
float du = (float)u * invSamples, dv = (float)v * invSamples;
// Figure out x,y pixel in NDC
float px = (x + du - (w / 2.0f)) / (w / 2.0f);
float py = -(y + dv - (h / 2.0f)) / (h / 2.0f);
float ret = 0.f;
Ray ray;
Isect isect;
ray.org = 0.f;
// Poor man's perspective projection
ray.dir.x = px;
ray.dir.y = py;
ray.dir.z = -1.0;
vnormalize(ray.dir);
isect.t = 1.0e+17;
isect.hit = 0;
for (uniform int snum = 0; snum < 3; ++snum)
ray_sphere_intersect(isect, ray, spheres[snum]);
ray_plane_intersect(isect, ray, plane);
// Note use of 'coherent' if statement; the set of rays we
// trace will often all hit or all miss the scene
if (isect.hit) {
ret = ambient_occlusion(isect, plane, spheres, rngstate);
ret *= invSamples * invSamples;
int offset = 3 * (y * w + x);
atomic_add_local(&image[offset], ret);
atomic_add_local(&image[offset+1], ret);
atomic_add_local(&image[offset+2], ret);
}
}
}
export void ao_ispc(uniform int w, uniform int h, uniform int nsubsamples,
uniform float image[]) {
ao_scanlines(0, h, w, h, nsubsamples, image);
}
static void task ao_task(uniform int width, uniform int height,
uniform int nsubsamples, uniform float image[]) {
ao_scanlines(taskIndex, taskIndex+1, width, height, nsubsamples, image);
}
export void ao_ispc_tasks(uniform int w, uniform int h, uniform int nsubsamples,
uniform float image[]) {
launch[h] ao_task(w, h, nsubsamples, image);
}

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/*
Copyright (c) 2010-2011, Intel Corporation
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of Intel Corporation nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS
#define NOMINMAX
#pragma warning (disable: 4244)
#pragma warning (disable: 4305)
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#ifdef __linux__
#include <malloc.h>
#endif
#include <math.h>
#include <map>
#include <string>
#include <algorithm>
#include <sys/types.h>
#include "ao_ispc.h"
using namespace ispc;
#include "../timing.h"
#include <sys/time.h>
static inline double rtc(void)
{
struct timeval Tvalue;
double etime;
struct timezone dummy;
gettimeofday(&Tvalue,&dummy);
etime = (double) Tvalue.tv_sec +
1.e-6*((double) Tvalue.tv_usec);
return etime;
}
#define NSUBSAMPLES 2
extern void ao_serial(int w, int h, int nsubsamples, float image[]);
static unsigned int test_iterations;
static unsigned int width, height;
static unsigned char *img;
static float *fimg;
static unsigned char
clamp(float f)
{
int i = (int)(f * 255.5);
if (i < 0) i = 0;
if (i > 255) i = 255;
return (unsigned char)i;
}
static void
savePPM(const char *fname, int w, int h)
{
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
img[3 * (y * w + x) + 0] = clamp(fimg[3 *(y * w + x) + 0]);
img[3 * (y * w + x) + 1] = clamp(fimg[3 *(y * w + x) + 1]);
img[3 * (y * w + x) + 2] = clamp(fimg[3 *(y * w + x) + 2]);
}
}
FILE *fp = fopen(fname, "wb");
if (!fp) {
perror(fname);
exit(1);
}
fprintf(fp, "P6\n");
fprintf(fp, "%d %d\n", w, h);
fprintf(fp, "255\n");
fwrite(img, w * h * 3, 1, fp);
fclose(fp);
printf("Wrote image file %s\n", fname);
}
int main(int argc, char **argv)
{
if (argc != 4) {
printf ("%s\n", argv[0]);
printf ("Usage: ao [num test iterations] [width] [height]\n");
getchar();
exit(-1);
}
else {
test_iterations = atoi(argv[1]);
width = atoi (argv[2]);
height = atoi (argv[3]);
}
// Allocate space for output images
img = new unsigned char[width * height * 3];
fimg = new float[width * height * 3];
//
// Run the ispc path, test_iterations times, and report the minimum
// time for any of them.
//
double minTimeISPC = 1e30;
#if 0
for (unsigned int i = 0; i < test_iterations; i++) {
memset((void *)fimg, 0, sizeof(float) * width * height * 3);
assert(NSUBSAMPLES == 2);
reset_and_start_timer();
ao_ispc(width, height, NSUBSAMPLES, fimg);
double t = get_elapsed_mcycles();
minTimeISPC = std::min(minTimeISPC, t);
}
// Report results and save image
printf("[aobench ispc]:\t\t\t[%.3f] million cycles (%d x %d image)\n",
minTimeISPC, width, height);
savePPM("ao-ispc.ppm", width, height);
#endif
//
// Run the ispc + tasks path, test_iterations times, and report the
// minimum time for any of them.
//
double minTimeISPCTasks = 1e30;
for (unsigned int i = 0; i < test_iterations; i++) {
memset((void *)fimg, 0, sizeof(float) * width * height * 3);
assert(NSUBSAMPLES == 2);
reset_and_start_timer();
const double t0 = rtc();
ao_ispc_tasks(width, height, NSUBSAMPLES, fimg);
double t = (rtc() - t0); //get_elapsed_mcycles();
minTimeISPCTasks = std::min(minTimeISPCTasks, t);
}
// Report results and save image
printf("[aobench ispc + tasks]:\t\t[%.3f] million cycles (%d x %d image)\n",
minTimeISPCTasks, width, height);
savePPM("ao-ispc-tasks.ppm", width, height);
return 0;
//
// Run the serial path, again test_iteration times, and report the
// minimum time.
//
double minTimeSerial = 1e30;
for (unsigned int i = 0; i < test_iterations; i++) {
memset((void *)fimg, 0, sizeof(float) * width * height * 3);
reset_and_start_timer();
ao_serial(width, height, NSUBSAMPLES, fimg);
double t = get_elapsed_mcycles();
minTimeSerial = std::min(minTimeSerial, t);
}
// Report more results, save another image...
printf("[aobench serial]:\t\t[%.3f] million cycles (%d x %d image)\n", minTimeSerial,
width, height);
printf("\t\t\t\t(%.2fx speedup from ISPC, %.2fx speedup from ISPC + tasks)\n",
minTimeSerial / minTimeISPC, minTimeSerial / minTimeISPCTasks);
savePPM("ao-serial.ppm", width, height);
return 0;
}