squiggle.c

commit b497b5b399b0bab278ac450b8d4a1fc55c79e16d
parent 3bb2804ccf2db29dfe59ba077fe731d9697762af
Author: NunoSempere <nuno.sempere@protonmail.com>
Date:   Sat, 13 Jan 2024 00:50:51 +0100

remove loop unrolling again

Diffstat:
M
squiggle_more.c
 | 
17
-----------------

1 file changed, 0 insertions(+), 17 deletions(-)
diff --git a/squiggle_more.c b/squiggle_more.c
@@ -75,23 +75,6 @@ void sampler_parallel(double (*sampler)(uint64_t* seed), double* results, int n_
                 // b) trying to unroll loops actually makes the code slower
                 // c) 8 results[j] are 8 doubles, which fit a cache line. If n_samples/n_threads
             }
-            // Failed loop unrolling
-            /*
-            for (int j = lower_bound_inclusive; j < 4*(upper_bound_not_inclusive/4); j++) {
-                results[j+0] = sampler(&(cache_box[i].seed));
-                results[j+1] = sampler(&(cache_box[i].seed));
-                results[j+2] = sampler(&(cache_box[i].seed));
-                results[j+3] = sampler(&(cache_box[i].seed));
-                // In principle, these results[j] could also result in two threads competing for the same cache line.
-                // In practice, though,
-                // a) this would happen infrequently
-                // b) trying to unroll loops actually makes the code slower
-                // c) 8 results[j] are 8 doubles, which fit a cache line. If n_samples/n_threads
-            }
-            for (int j = 4*(upper_bound_not_inclusive/4); j < upper_bound_not_inclusive; j++) {
-                results[j] = sampler(&(cache_box[i].seed));
-            }
-            */
         }
     }
     for (int j = divisor_multiple; j < n_samples; j++) {