Double presicion math in mandelbrot_avx

src/mandelbrot.c

@@ -31,37 +31,37 @@
 int
 mandelbrot_avx(Complex c)
 {
-    __m256 cr = _mm256_set1_ps(c.real);
-    __m256 ci = _mm256_set1_ps(c.imag);
+    __m256 cr = _mm256_set1_pd(c.real);
+    __m256 ci = _mm256_set1_pd(c.imag);
 
     __m256 zr = cr;
     __m256 zi = ci;
 
-    __m256 threshold = _mm256_set1_ps(4); 
+    __m256 threshold = _mm256_set1_pd(4); 
 
     int k = 1;
 
-    __m256 mk = _mm256_set1_ps(k);
-    __m256 one = _mm256_set1_ps(1);
+    __m256 mk = _mm256_set1_pd(k);
+    __m256 one = _mm256_set1_pd(1);
     while (++k < MAX_ITERATIONS){
         /* Compute z1 from z0 */
-        __m256 zr2 = _mm256_mul_ps(zr, zr);
-        __m256 zi2 = _mm256_mul_ps(zi, zi);
-        __m256 zrzi = _mm256_mul_ps(zr, zi);
+        __m256 zr2 = _mm256_mul_pd(zr, zr);
+        __m256 zi2 = _mm256_mul_pd(zi, zi);
+        __m256 zrzi = _mm256_mul_pd(zr, zi);
         /* zr1 = zr0 * zr0 - zi0 * zi0 + cr */
         /* zi1 = zr0 * zi0 + zr0 * zi0 + ci */
-        zr = _mm256_add_ps(_mm256_sub_ps(zr2, zi2), cr);
-        zi = _mm256_add_ps(_mm256_add_ps(zrzi, zrzi), ci);
+        zr = _mm256_add_pd(_mm256_sub_pd(zr2, zi2), cr);
+        zi = _mm256_add_pd(_mm256_add_pd(zrzi, zrzi), ci);
 
         /* Increment k */
-        zr2 = _mm256_mul_ps(zr, zr);
-        zi2 = _mm256_mul_ps(zi, zi);
-        __m256 mag2 = _mm256_add_ps(zr2, zi2);
-        __m256 mask = _mm256_cmp_ps(mag2, threshold, _CMP_LT_OS);
-        mk = _mm256_add_ps(_mm256_and_ps(mask, one), mk);
+        zr2 = _mm256_mul_pd(zr, zr);
+        zi2 = _mm256_mul_pd(zi, zi);
+        __m256 mag2 = _mm256_add_pd(zr2, zi2);
+        __m256 mask = _mm256_cmp_pd(mag2, threshold, _CMP_LT_OS);
+        mk = _mm256_add_pd(_mm256_and_pd(mask, one), mk);
 
         /* Early bailout? */
-        if (_mm256_testz_ps(mask, _mm256_set1_ps(-1)))
+        if (_mm256_testz_pd(mask, _mm256_set1_pd(-1)))
             break;
     }
     return k;