clean up graph dedup function [run_process_replay] (#5169)

tinygrad/codegen/uops.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 from typing import Iterator, Optional, Tuple, Any, Dict, List, DefaultDict, Set, Callable, Union, cast, TypeVar
 import functools, itertools, heapq, math
-from collections import defaultdict
+from collections import defaultdict, deque
 from enum import Enum, auto
 from dataclasses import dataclass, field
 from tinygrad.dtype import ConstType, dtypes, DType
@@ -334,23 +334,22 @@ class UOpGraph:
   def graph_dedup(self, sink:UOp):
     # add nodes to graph in reverse BFS order
     # dedup all nodes
-    # TODO: i feel like this BFS is written in a few places, possible to library it?
-    early_in_degree: Dict[UOp, int] = {}
+    in_degree: Dict[UOp, int] = {}
     children: Dict[UOp, List[UOp]] = {}
-    get_children_dfs(sink, children, early_in_degree)
+    get_children_dfs(sink, children, in_degree)
 
-    early_queue = [k for k, v in early_in_degree.items() if v == 0]
+    queue = deque([k for k, v in in_degree.items() if v == 0])
     replace_nodes: Dict[UOp, UOp] = {}
-    while len(early_queue):
-      n = early_queue.pop(0)
+    while queue:
+      n = queue.popleft()
       if n in replace_nodes: continue
       key = (n.op, n.dtype, tuple(replace_nodes.get(x, x) for x in n.src), n.arg)
       if found:=self.nodes.get(key): replace_nodes[n] = found
       else: replace_nodes[n] = self.nodes[key] = UOp(*key)
       for x in children[n]:
-        early_in_degree[x] -= 1
-        if early_in_degree[x] == 0:
-          early_queue.append(x)
+        in_degree[x] -= 1
+        if in_degree[x] == 0:
+          queue.append(x)
     return replace_nodes.get(sink, sink)
 
   def linearize(self, extra_pm:Optional[PatternMatcher]=None, type_verify=True):