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geohot eec82b0db4 revert wrong custom kernel fix 2026-08-05 18:27:40 -07:00
2 changed files with 0 additions and 47 deletions
-35
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@@ -127,41 +127,6 @@ class TestCustomKernel(unittest.TestCase):
# https://gpuweb.github.io/gpuweb/#abstract-opdef-encoder-bind-groups-alias-a-writable-resource
self.assertEqual(x.tolist(), [1, 2, 3, 4] if Device.DEFAULT != "WEBGPU" else [0, 1, 2, 3])
def test_lazy_const_srcs_with_reduce(self):
# lazy const expressions above a custom kernel call don't resolve to a buffer state, they must be realized.
# without this, the rangeify doesn't assign ranges to the subgraph above the call and reduce conversion crashes
x = Tensor.linspace(-1.0, 1.0, 64) # Tensor.arange is cumsum-based, so this contains a REDUCE with no buffer anchor
out = Tensor.empty_like(x)
def copy_kernel(out:UOp, inp:UOp) -> UOp:
i = UOp.range(inp.numel(), 0)
return UOp.group(out[i].store(inp[i])).end(i).sink(arg=KernelInfo(name="copy"))
# forge the call like llm/kernels does: params and call args, no Tensor.custom_kernel contiguous
params = tuple(UOp.placeholder_like(x, slot=i) for i,x in enumerate((out.uop, x.uop)))
call = copy_kernel(*params).call(out.uop, x.uop)
np.testing.assert_allclose(Tensor(out.uop.after(call)).realize().numpy(), x.realize().numpy(), rtol=1e-6)
def test_mixed_buffer_and_lazy_const_srcs(self):
# a computed input must be realized even if one of its sources resolves to a buffer: the CALL gives the whole
# subgraph no ranges, so the const branch still crashes reduce conversion if only the buffer branch is found
x = Tensor.linspace(-1.0, 1.0, 64) # lazy const expression with a REDUCE
y = Tensor.ones(64).contiguous().realize()
out = Tensor.empty_like(x)
def copy_kernel(out:UOp, inp:UOp) -> UOp:
i = UOp.range(inp.numel(), 0)
return UOp.group(out[i].store(inp[i])).end(i).sink(arg=KernelInfo(name="copy"))
for expr in (y + x, x + y, y * 2.0): # buffer on either side, and a scalar const over a buffer
params = tuple(UOp.placeholder_like(u, slot=i) for i,u in enumerate((out.uop, expr.uop)))
call = copy_kernel(*params).call(out.uop, expr.uop)
np.testing.assert_allclose(Tensor(out.uop.after(call)).realize().numpy(), expr.realize().numpy(), rtol=1e-6)
# view-only movement ops over a buffer resolve to the buffer state and must NOT be realized
expr = y.reshape(8, 8).reshape(64)
expected = expr.numpy()
params = tuple(UOp.placeholder_like(u, slot=i) for i,u in enumerate((out.uop, expr.uop)))
call = copy_kernel(*params).call(out.uop, expr.uop)
GlobalCounters.kernel_count = 0
np.testing.assert_allclose(Tensor(out.uop.after(call)).realize().numpy(), expected, rtol=1e-6)
self.assertEqual(GlobalCounters.kernel_count, 1, "a view over a buffer should not add a realize kernel")
def test_simple_sharded(self):
devs = ("CPU:0", "CPU:1")
-12
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@@ -27,19 +27,7 @@ def realize_store_after_src(ctx:dict[UOp, None], dest:UOp, src:UOp):
BUFFER_STATE_OPS: set[Ops] = {Ops.AFTER, Ops.BUFFER, Ops.PARAM, Ops.MSELECT, Ops.MSTACK, Ops.BIND}
def realize_custom_kernel_srcs(ctx:dict[UOp, None], c:UOp) -> None:
# the inputs of a custom kernel must resolve to a buffer state. realize the ones that don't (e.g. lazy const
# expressions above the call), otherwise a reduce in that subgraph has no ranges and crashes in rangeify.
# NOTE: only view-only movement ops preserve the underlying buffer. anything computed (ALU, REDUCE, ...) must be
# realized even if one of its sources is a buffer, since the CALL gives the whole subgraph no ranges
for s in c.src[1:]:
t = s
while t.op in GroupOp.Movement and len(t.src): t = t.src[0]
if t.op not in BUFFER_STATE_OPS: ctx[s] = None
pm_generate_realize_map = PatternMatcher([
# realize the inputs of custom kernel calls
(UPat(Ops.CALL, src=(UPat(Ops.SINK),), name="c", allow_any_len=True), realize_custom_kernel_srcs),
# always realize
(UPat({Ops.CONTIGUOUS, Ops.STORE}, name="tr"), realize),
# realize srcs of these