--- a/src/hotspot/share/adlc/output_c.cpp	Tue Nov 26 16:09:23 2019 +0300
+++ b/src/hotspot/share/adlc/output_c.cpp	Tue Nov 26 16:09:25 2019 +0300
@@ -2781,6 +2781,8 @@
       // Return the sole RegMask.
       if (strcmp(first_reg_class, "stack_slots") == 0) {
         fprintf(fp,"  return &(Compile::current()->FIRST_STACK_mask());\n");
+      } else if (strcmp(first_reg_class, "dynamic") == 0) {
+        fprintf(fp,"  return &RegMask::Empty;\n");
       } else {
         const char* first_reg_class_to_upper = toUpper(first_reg_class);
         fprintf(fp,"  return &%s_mask();\n", first_reg_class_to_upper);