Merge pull request #124 from GraphStreamingProject/likely_if

Faster fast with branch prediction
GraphStreamingProject · Feb 15, 2023 · 28e23eb · 28e23eb
2 parents f7196f7 + 6a33a14
commit 28e23eb
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diff --git a/include/types.h b/include/types.h
@@ -24,3 +24,6 @@ struct GraphUpdate {
   Edge edge;
   UpdateType type;
 };
+
+#define likely_if(x) if(__builtin_expect((bool)(x), true))
+#define unlikely_if(x) if (__builtin_expect((bool)(x), false))
diff --git a/src/l0_sampling/sketch.cpp b/src/l0_sampling/sketch.cpp
@@ -64,7 +64,7 @@ void Sketch::update(const vec_t update_idx) {
   for (unsigned i = 0; i < num_buckets; ++i) {
     col_hash_t depth = Bucket_Boruvka::get_index_depth(update_idx, seed + i, num_guesses);
     size_t bucket_id = i * num_guesses + depth;
-    if (depth < num_guesses)
+    likely_if(depth < num_guesses)
       Bucket_Boruvka::update(bucket_a[bucket_id], bucket_c[bucket_id], update_idx, checksum);
   }
 }