hotfix: prevent inf loop if reduce splits

tinygrad/codegen/late/linearizer.py

@@ -64,7 +64,10 @@ class CFGContext:
       # ranges that have dependencies on other siblings need to be scheduled after them
       order = sorted(v, key=lambda x: len([u for u in v if u in deps[x]]))
       zipped = zip(order, order[1:]) if k.op is Ops.SINK else zip([k.src[1]] + order, order)
-      for x,y in zipped: self.edges[y.src[1]] = x
+      for x,y in zipped:
+        # TODO: this can happen! it causes infinite loop in shufflenet
+        assert y.src[1] not in x.backward_slice_with_self
+        self.edges[y.src[1]] = x
 
 pm_add_control_flow = PatternMatcher([
   (UPat(Ops.RANGE, name="x"), lambda ctx,x: x.replace(src=x.src+(y,)) if (y:=ctx.edges.get(x)) is not None else None),

tinygrad/uop/symbolic.py

@@ -452,7 +452,7 @@ def _valid_priority(v: UOp, valids:list[UOp]):
   return sum(-1 if (res:=parse_valid(v)) is not None and res[0] in other.toposort() else 0 for other in valids)
 
 def simplify_valid(valid:UOp) -> UOp|None:
-  if valid.op_in_backward_slice_with_self(Ops.LOAD): return None  # this should only be for indexing, skip if there's a LOAD
+  if valid.op_in_backward_slice_with_self(Ops.INDEX): return None  # this should only be for indexing, skip if there's a INDEX
   ret:list[UOp] = []
   something_changed = False
   valids = list(valid.split_uop(Ops.AND))