u3: further optimizes u3i_edit, inlining axis bit math

urbit · May 1, 2023 · bec84ac · bec84ac
1 parent dcda46f
commit bec84ac
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/pkg/noun/imprison.c b/pkg/noun/imprison.c
@@ -611,12 +611,15 @@ u3i_edit(u3_noun big, u3_noun axe, u3_noun som)
     case 1: break;
 
     default: {
-      c3_w dep_w = u3r_met(0, u3x_atom(axe)) - 2;
+      c3_w        dep_w = u3r_met(0, u3x_atom(axe)) - 2;
+      const c3_w* axe_w = ( c3y == u3a_is_cat(axe) )
+                        ? &axe
+                        : ((u3a_atom*)u3a_to_ptr(axe))->buf_w;
 
       do {
         u3a_cell*  big_u = u3a_to_ptr(big);
         u3_noun*     old = (u3_noun*)&(big_u->hed);
-        const c3_y bit_y = u3r_bit(dep_w, axe);
+        const c3_y bit_y = 1 & (axe_w[dep_w >> 5] >> (dep_w & 31));
 
         if ( c3n == u3a_is_cell(big) ) {
           return u3m_bail(c3__exit);