1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
#include "mandel.h"
int mandelbrot(double ca, double cb, int iterations)
{
double zr = ca;
double zi = cb;
double zr_square;
double zi_square;
int n;
for (n = 0; n < iterations; n++)
{
zi_square = zi * zi;
zr_square = zr * zr;
if (zr_square + zi_square > 4.0)
return n;
zi = 2.0 * zr * zi;
zr = zr_square - zi_square;
zi += cb;
zr += ca;
}
return n;
}
void mandelbrot_avx(State *state, Color *pixels, int width, int height)
{
__m256d real_step = _mm256_set1_pd((state->real_end - state->real_end) / (double)width);
__m256d imag_step = _mm256_set1_pd((state->imag_end - state->imag_end) / (double)height);
__m256i ones = _mm256_set1_epi64x(1);
__m256i iterations = _mm256_set1_epi64x(state->iterations);
__m256d twos = _mm256_set1_pd(2.0);
__m256d fours = _mm256_set1_pd(4.0);
__m256d offset = _mm256_setr_pd(0.0, 1.0, 2.0, 3.0);
__m256d ci = _mm256_set1_pd(0.0);
for (int y = 0; y < height; y++)
{
__m256d cr = _mm256_set1_pd(0.0);
for (int x = 0; x < width; x += 4)
{
__m256d zr = cr;
__m256d zi = ci;
__m256d zr_square;
__m256d zi_square;
__m256i n;
/* while { */
zi_square = _mm256_mul_pd(zi, zi);
zr_square = _mm256_mul_pd(zr, zr);
__m256d dist = _mm256_add_pd(zi_square, zr_square);
__m256d escaped = _mm256_cmp_pd(dist, fours, _CMP_LT_OQ);
// zi = 2.0 * zi * zr
zi = _mm256_mul_pd(zi, zr);
zi = _mm256_mul_pd(zi, twos);
zr = _mm256_sub_pd(zr_square, zi_square);
zi = _mm256_add_pd(zi, ci);
zr = _mm256_add_pd(zr, cr);
/* } */
cr = _mm256_add_pd(cr, real_step);
}
ci = _mm256_add_pd(ci, imag_step);
}
}
|
