From c5b2b9242dc5e9398cff1e8d0102a118cfbbbd6a Mon Sep 17 00:00:00 2001
From: chenyu <chenyu@fastmail.com>
Date: Thu, 23 Jul 2026 02:02:44 -0400
Subject: [PATCH] python speed tweak for compile3 (#17147)

---
 tinygrad/engine/realize.py    | 6 ++++--
 tinygrad/schedule/rangeify.py | 2 +-
 tinygrad/uop/symbolic.py      | 5 ++---
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/tinygrad/engine/realize.py b/tinygrad/engine/realize.py
index 3a64d7b0bf..482133e3ce 100644
--- a/tinygrad/engine/realize.py
+++ b/tinygrad/engine/realize.py
@@ -89,11 +89,13 @@ def optimize_local_size(call:UOp, prg:UOp) -> UOp|None:
   if prg.arg.local_size is not None or not Device[device].renderer.has_local or not all_int(prg.arg.global_size): return None
 
   if (local_size:=local_size_cache.get(prg.key)) is None:
-    bufs = [UOp.from_buffer(b.allocate()) for b in bufs_from_ast(prg.src[0], device)]
+    # reuse one loaded runtime across candidates, only launch dims vary
+    bufs, runtime = [b.allocate() for b in bufs_from_ast(prg.src[0], device)], get_runtime(device, prg, cache=False)
     def try_exec(local_size):
       try:
         new_gs = tuple(g//l if g%l == 0 else g/l for g,l in zip(prg.arg.global_size, local_size))
-        return time_call(prg.replace(arg=replace(prg.arg, global_size=new_gs, local_size=tuple(local_size))).call(*bufs))
+        return runtime(*[bufs[i].get_buf(device) for i in prg.arg.globals], global_size=new_gs, local_size=(*local_size,),
+                       vals=prg.arg.vals({}), wait=True)
       except Exception: return float('inf')
 
     MAX_WORKGROUP = 1024
diff --git a/tinygrad/schedule/rangeify.py b/tinygrad/schedule/rangeify.py
index bd1a3162ee..400649d7ea 100644
--- a/tinygrad/schedule/rangeify.py
+++ b/tinygrad/schedule/rangeify.py
@@ -60,9 +60,9 @@ pm_mops = PatternMatcher([
 # 0. do some cleanup rewrites, mostly copied from the old stuff
 
 def fix_store_hazard(target:UOp, src:UOp):
+  if (base:=target.base) not in src.backward_slice_with_self: return None
   # PERMUTE and FLIP reorder indices, SHRINK can have overlapping regions when dest is also shrunk
   unsafe = {Ops.PERMUTE, Ops.FLIP} | ({Ops.SHRINK} if target.op_in_backward_slice_with_self(Ops.SHRINK) else set())
-  base = target.base
   reaches_base: dict[UOp, bool] = {}
   for s in src.toposort(gate=lambda s: s.op is not Ops.CONTIGUOUS):
     reaches_base[s] = s is base or any(reaches_base.get(c) for c in s.src)
diff --git a/tinygrad/uop/symbolic.py b/tinygrad/uop/symbolic.py
index 3d07200640..fffa74a2fe 100644
--- a/tinygrad/uop/symbolic.py
+++ b/tinygrad/uop/symbolic.py
@@ -332,9 +332,8 @@ def uop_given_valid(valid:UOp, uop:UOp, try_simplex=True) -> UOp:
 
       for candidate in candidates:
         # if every branch in candidate gives the same simplified uop, we can rewrite the uop
-        newuops = [uop.substitute({X:newX}) for X,newX in candidate]
-        if any(u is uop for u in newuops): continue  # if any branch doesnt appear in uop, skip
-        newuops = [u.simplify().substitute({newX:X}).simplify() for (X,newX),u in zip(candidate,newuops)]
+        if any(X not in uop.backward_slice_with_self for X,_ in candidate): continue  # skip if a branch var isn't in uop
+        newuops = [uop.substitute({X:newX}).simplify().substitute({newX:X}).simplify() for X,newX in candidate]
         if all_same(newuops): uop = newuops[0]
         elif uop.op is Ops.STACK and len(uop.src) == 2:
           if all_same([uops.src[0] for uops in newuops]): uop = uop.replace(src=(newuops[0].src[0], uop.src[1]))