MLBEDSW-4034: New Scheduler Size or Performance Optimisation

 - Merged dev/scheduler at 83639f90e8c828f70de6e29142355a940224959b

Signed-off-by: Tim Hall <tim.hall@arm.com>
Change-Id: I0050529d4b42da93768c7264296434dd877fb5b4
diff --git a/ethosu/vela/numeric_util.py b/ethosu/vela/numeric_util.py
index d596209..011765f 100644
--- a/ethosu/vela/numeric_util.py
+++ b/ethosu/vela/numeric_util.py
@@ -24,6 +24,10 @@
     return ((a + b - 1) // b) * b
 
 
+def round_down(a, b):
+    return (a // b) * b
+
+
 def round_up_divide(a, b):
     return (a + b - 1) // b