FIx logic in xnn_use_nr2 to match the previous behaviour.

src/microkernel-utils.c

@@ -155,17 +155,15 @@ size_t xnn_gemm_best_tile_size(size_t num_groups, size_t m, size_t n,
 
 // Checks whether to use the `nr2` config or not.
 bool xnn_use_nr2(size_t nr, size_t nr2, size_t output_channels) {
-  size_t nr_overcompute = (nr - output_channels % nr) % nr;
-  size_t nr2_overcompute = (nr2 - output_channels % nr2) % nr2;
-  // Switch to alternative microkernel when:
-  // 1. Alternative microkernel better supports fewer output channels, or
-  // 2. Alternative microkernel has less overcompute and default wastes >1% of
-  // output channels
-  if (nr > output_channels || (nr2_overcompute < nr_overcompute &&
-                               nr_overcompute * 100 > output_channels)) {
-    // Default microkernel is suboptimal, use a microkernel that better
-    // supports fewer output channels.
-    return true;
+  if (nr > output_channels) {
+    size_t nr_overcompute = (nr - output_channels % nr) % nr;
+    size_t nr2_overcompute = (nr2 - output_channels % nr2) % nr2;
+    // Switch to alternative microkernel when:
+    // 1. Alternative microkernel better supports fewer output channels, or
+    // 2. Alternative microkernel has less overcompute and default wastes >1% of
+    // output channels
+    return nr2_overcompute < nr_overcompute &&
+           nr_overcompute * 100 > output_channels;
   }
   return false;
 }