diff --git a/tgt-sizer/scan_lpms.cc b/tgt-sizer/scan_lpms.cc
index 18dcbb7d8..a5164f594 100644
--- a/tgt-sizer/scan_lpms.cc
+++ b/tgt-sizer/scan_lpms.cc
@@ -125,6 +125,7 @@ void scan_lpms(ivl_scope_t scope, struct sizer_statistics&stats)
 		case IVL_LPM_CONCAT:
 		case IVL_LPM_CONCATZ:
 		case IVL_LPM_REPEAT:
+		case IVL_LPM_SUBSTITUTE:
 		  break;
 
 		case IVL_LPM_ADD: