From a9d91ffcfcc508cabeaa2b7f80840be90222cc29 Mon Sep 17 00:00:00 2001
From: George Hotz <geohot@gmail.com>
Date: Wed, 29 Oct 2025 17:22:59 +0800
Subject: [PATCH] DEMOTE op for putting globals in locals

---
 test/test_rangeify.py             |  7 +++++++
 tinygrad/codegen/opt/__init__.py  |  1 +
 tinygrad/codegen/opt/postrange.py | 17 +++++++++++++++++
 tinygrad/uop/__init__.py          |  1 +
 tinygrad/uop/ops.py               |  2 +-
 5 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/test/test_rangeify.py b/test/test_rangeify.py
index b47da8fb98..5146c3bc13 100644
--- a/test/test_rangeify.py
+++ b/test/test_rangeify.py
@@ -143,6 +143,13 @@ class TestPcontig(unittest.TestCase):
     print(f"mse: {mse}")
     self.assertLessEqual(mse, 1e-6)
 
+  def test_flash_attention_tc(self):
+    opts = ()
+    # rows in all the matrix
+    opts += (Opt(OptOps.DEMOTE, 4, 8),)
+    #opts += (Opt(OptOps.TC, 0, (0, 0, 1)),)
+    self.test_flash_attention(opts)
+
   def test_flash_attention_opt(self):
     opts = ()
     # columns in top matrix
diff --git a/tinygrad/codegen/opt/__init__.py b/tinygrad/codegen/opt/__init__.py
index fb4b84ddee..944e37ac8d 100644
--- a/tinygrad/codegen/opt/__init__.py
+++ b/tinygrad/codegen/opt/__init__.py
@@ -6,6 +6,7 @@ from dataclasses import dataclass
 class OptOps(Enum):
   TC = auto(); UPCAST = auto(); UNROLL = auto(); LOCAL = auto(); THREAD = auto() # noqa: E702
   GROUP = auto(); GROUPTOP = auto(); NOLOCALS = auto(); PADTO = auto(); SWAP = auto() # noqa: E702
+  DEMOTE = auto()
   def __lt__(self, x:OptOps): return self.value < x.value
 
 @dataclass(frozen=True, order=True)
diff --git a/tinygrad/codegen/opt/postrange.py b/tinygrad/codegen/opt/postrange.py
index 968210878a..f8d4c3ac3a 100644
--- a/tinygrad/codegen/opt/postrange.py
+++ b/tinygrad/codegen/opt/postrange.py
@@ -174,6 +174,23 @@ class Scheduler:
         check(not self.dont_use_locals, "can't use locals")
         check(rng.arg[-1] == AxisType.REDUCE, "group is for reduce")
       ret = self.shift_to(rng, amt, opt_to_at[opt.op], top=opt.op in {OptOps.GROUPTOP, OptOps.THREAD})
+    elif opt.op is OptOps.DEMOTE:
+      _, rr = self.shift_to(rng, cast(int, opt.arg), AxisType.LOOP)
+      def do_demote(ctx, x:UOp):
+        if x.tag is not None: return None
+        mr = ctx[0]
+        nr = mr.replace(arg=ctx[0].arg[0:-2]+(mr.arg[-2]+1, mr.arg[-1]))
+        ctx[0] = nr
+        buf = x.replace(src=(x.src[0], mr)+x.src[1:], tag=1).substitute({mr:nr})
+        return UOp(Ops.APPENDINDEX, dtypes.void, (buf,mr))
+      # do the demotion
+      pm_demote = PatternMatcher([
+        (UPat(Ops.END, src=(UPat(Ops.END, name="e1"),), allow_any_len=True, name="e2"), lambda e1,e2: e1.replace(src=e1.src+e2.src[1:])),
+        (UPat(Ops.BUFFERIZE, name="x"), do_demote),
+        (UPat(Ops.INDEX, src=(UPat(Ops.APPENDINDEX, name="x"),), name="y", allow_any_len=True),
+         lambda x,y: y.replace(src=(x.src[0],)+x.src[1:]+y.src[1:])),
+      ])
+      self.ast = graph_rewrite(self.ast.src[0].end(rr).sink(), pm_demote, ctx=[rr], bottom_up=True, name="demote")
     elif opt.op is OptOps.TC:
       check(len(self.applied_opts) == 0, "tensor core opts must be first") # TODO: remove the need for this by having warps
       check(opt.axis is not None, "tensor core opts must have an axis")
diff --git a/tinygrad/uop/__init__.py b/tinygrad/uop/__init__.py
index cad734d6d0..7c0b0b3b46 100644
--- a/tinygrad/uop/__init__.py
+++ b/tinygrad/uop/__init__.py
@@ -59,6 +59,7 @@ class Ops(FastEnum):
 
   # INDEX is a BinaryOp similar to ADD, but it operates on pointers
   INDEX = auto()
+  APPENDINDEX = auto()
 
   # BinaryOps
   ADD = auto(); MUL = auto(); SHL = auto(); SHR = auto(); IDIV = auto(); MAX = auto(); MOD = auto() # noqa: E702
diff --git a/tinygrad/uop/ops.py b/tinygrad/uop/ops.py
index 263269a222..b03782599b 100644
--- a/tinygrad/uop/ops.py
+++ b/tinygrad/uop/ops.py
@@ -188,7 +188,7 @@ class UOp(MathTrait, metaclass=UOpMetaClass):
     match self.op:
       # late ops don't have shape
       case Ops.UNIQUE | Ops.DEVICE | Ops.RANGE | Ops.INDEX | Ops.LOAD | Ops.IF | Ops.BARRIER | Ops.CUSTOM | Ops.CUSTOMI | \
-           Ops.VECTORIZE | Ops.VCONST | Ops.GEP | Ops.SPECIAL | Ops.UNROLL | Ops.PRECAST:
+           Ops.VECTORIZE | Ops.VCONST | Ops.GEP | Ops.SPECIAL | Ops.UNROLL | Ops.PRECAST | Ops.CONTRACT | Ops.APPENDINDEX:
         return None
 
       # some ops init the shape