restore SUPEROPT_GC, SUPEROPT_VM

Author: dhalbert

py/py.mk

@@ -292,11 +292,25 @@ $(BUILD)/shared/libc/string0.o: CFLAGS += $(CFLAGS_BUILTIN)
 # that the function preludes are of a minimal and predictable form.
 $(PY_BUILD)/nlr%.o: CFLAGS += -Os
 
+# CIRCUITPY: separate SUPEROPT for gc.o and vm.o
 # optimising gc for speed; 5ms down to 4ms on pybv2
+ifndef SUPEROPT_GC
+  SUPEROPT_GC = 1
+endif
+
+ifeq ($(SUPEROPT_GC),1)
 $(PY_BUILD)/gc.o: CFLAGS += $(CSUPEROPT)
+endif
 
 # optimising vm for speed, adds only a small amount to code size but makes a huge difference to speed (20% faster)
+ifndef SUPEROPT_VM
+  SUPEROPT_VM = 1
+endif
+
+ifeq ($(SUPEROPT_VM),1)
 $(PY_BUILD)/vm.o: CFLAGS += $(CSUPEROPT)
+endif
+
 # Optimizing vm.o for modern deeply pipelined CPUs with branch predictors
 # may require disabling tail jump optimization. This will make sure that
 # each opcode has its own dispatching jump which will improve branch