variables should not be weakints

.github/workflows/test.yml

@@ -86,27 +86,6 @@ jobs:
     - name: Custom tests
       run: DEV=CPU:LLVM GPUS=4 TINY_BACKEND=1 python3 -m pytest -nauto extra/torch_backend/test.py extra/torch_backend/test_inplace.py extra/torch_backend/test_multigpu.py extra/torch_backend/test_kernel_fusion.py --durations=20
 
-  torchbackendtrain:
-    name: Torch Backend Training
-    runs-on: ${{ github.repository == 'tinygrad/tinygrad' && github.event_name == 'pull_request' && github.event.pull_request.author_association == 'COLLABORATOR' && 'namespace-profile-tinygrad' || 'ubuntu-24.04' }}
-    timeout-minutes: 15
-    steps:
-    - name: Checkout Code
-      uses: actions/checkout@v6
-    - name: Setup Environment
-      uses: ./.github/actions/setup-tinygrad
-      with:
-        key: torch-backend-pillow-torchvision-et-pt
-        deps: testing_unit
-        pydeps: "pillow torchvision expecttest"
-        llvm: 'true'
-    - name: Install ninja
-      run: |
-        sudo apt update || true
-        sudo apt install -y --no-install-recommends ninja-build
-    - name: Test beautiful_mnist in torch with TINY_BACKEND
-      run: STEPS=20 DEV=CPU TARGET_EVAL_ACC_PCT=90.0 MAX_BUFFER_SIZE=0 TINY_BACKEND=1 python3 examples/other_mnist/beautiful_mnist_torch.py
-
   bepython:
     name: Python Backend
     runs-on: ${{ github.repository == 'tinygrad/tinygrad' && github.event_name == 'pull_request' && github.event.pull_request.author_association == 'COLLABORATOR' && 'namespace-profile-tinygrad' || 'ubuntu-24.04' }}

README.md

@@ -140,7 +140,7 @@ Documentation along with a quick start guide can be found on the [docs website](
 ```python
 from tinygrad import Tensor
 
-x = Tensor.eye(3).clone()  # clone to make it a buffer
+x = Tensor.eye(3)
 y = Tensor([[2.0,0,-2.0]])
 z = y.matmul(x).sum()
 z.backward()

extra/hcq2/ops_amd2.py

@@ -561,7 +561,9 @@ class AMDDevice(HCQ2Compiled):
   def is_usb(self) -> bool: return False
 
   def __init__(self, device:str=""):
-    self.iface = self._select_iface(device)
+    self.device_id = int(device.split(":")[1]) if ":" in device else 0
+
+    self.iface = self._select_iface()
 
     self.target:tuple[int, ...] = ((trgt:=self.iface.props['gfx_target_version']) // 10000, (trgt // 100) % 100, trgt % 100)
     self.arch = "gfx%d%x%x" % self.target

extra/thunder/tiny/tk/tiles.py

@@ -209,7 +209,7 @@ class ST:
     return cls(uop, rows, cols, layout, base_shape, ker)
 
   def swizzle(self, row, col):
-    swizzled_offset = self.base_shape.swizzle(row, col, self._uop.dtype)
+    swizzled_offset = self.base_shape.swizzle(row, col, self._uop.dtype.scalar())
 
     row = swizzled_offset // self.base_shape.cols
     col = swizzled_offset % self.base_shape.cols

extra/torch_backend/backend.py

@@ -4,7 +4,7 @@
 # A006 Lambda argument `input` is shadowing a Python builtin
 from tinygrad import Tensor, dtypes, Device
 from tinygrad.uop.ops import Ops, GroupOp
-from tinygrad.helpers import getenv, prod, strides_for_shape
+from tinygrad.helpers import getenv, prod, strides_for_shape, argfix
 import torch.lib
 TORCH_DEBUG = getenv("TORCH_DEBUG")
 import torch, pathlib, operator, functools, weakref
@@ -88,6 +88,9 @@ view_ops = {
   "aten.diagonal": Tensor.diagonal,
   }
 
+# torch 2.10 handles this natively
+if tuple(map(int, torch.__version__.split('.')[:2])) < (2, 10): view_ops.update({"aten.detach": Tensor.detach})
+
 for k,v in view_ops.items(): torch.library.impl(k.replace("aten.", "aten::"), "privateuseone")(wrap_view_op(v))
 
 def _get_view_ops(view): return getattr(view, "_view_ops", [])
@@ -96,21 +99,46 @@ def _apply_view_ops(target, ops):
   for fn, args, kwargs in ops: target = fn(target, *args, **kwargs)
   return target
 
-# a chain of reshapes is undone by reshaping the value back to the base
+# similar to https://github.com/pytorch/pytorch/blob/main/aten/src/ATen/InferSize.h
+def _reshape_target_shape(shape:tuple[int, ...], args) -> tuple[int, ...]|None:
+  if not (req := argfix(*args)): return None
+  new_shape, infer_idx = [], -1
+  for i, s in enumerate(req):
+    if s is None: s = shape[i] if i < len(shape) else None
+    if not isinstance(s, int): return None
+    if s == -1:
+      if infer_idx != -1: return None
+      infer_idx = len(new_shape)
+    new_shape.append(s)
+  total = prod(shape)
+  if infer_idx != -1:
+    known = prod(x for x in new_shape if x != -1)
+    if known == 0:
+      if total != 0: return None
+      new_shape[infer_idx] = 0
+    else: new_shape[infer_idx] = total // known
+  return tuple(new_shape) if prod(new_shape) == total else None
+
+# TODO: can we get rid of this? only for test_flatten_reshape_add
 def _try_simple_reshape_view_write(base: Tensor, view: Tensor, val: Tensor) -> bool:
   if not (ops := _get_view_ops(view)): return False
-  if any(fn is not Tensor.reshape for fn, _, _ in ops): return False
-  base.assign(val.reshape(base.shape))
+  shapes = [base.shape]
+  for fn, args, _ in ops:
+    if fn is Tensor.reshape:
+      if not (next_shape := _reshape_target_shape(shapes[-1], args)): return False
+      shapes.append(next_shape)
+  if shapes[-1] != view.shape: return False
+  for s in reversed(shapes[:-1]): val = val.reshape(s)
+  base.assign(val)
   return True
 
 def _view_write(base: Tensor, view: Tensor, value: Tensor) -> None:
   val = value if value.dtype == base.dtype else value.cast(base.dtype)
+  if view.shape == base.shape: return base.assign(val)
   if _try_simple_reshape_view_write(base, view, val): return
   idx_base = Tensor.arange(base.numel(), dtype=dtypes.int32).reshape(base.shape)
   idx_view = _apply_view_ops(idx_base, _get_view_ops(view)).reshape(-1)
-  # clone, not contiguous: contiguous() on a base that already owns its buffer returns the base itself, and scattering
-  # into that is an in-place write to a buffer other tensors still hold, which setitem refuses
-  flat_base = base.reshape(base.numel()).clone()
+  flat_base = base.reshape(base.numel()).contiguous()
   flat_base[idx_view] = val.reshape(-1)
   base.assign(flat_base.reshape(base.shape))
 
@@ -273,34 +301,6 @@ def slice_tensor(self, dim=0, start=None, end=None, step=1):
   slices[dim] = slice(start, end, step)
   return self[slices]
 
-# the functional scatters. without an impl aten falls back to a path that assumes a real storage: "self.has_storage() INTERNAL ASSERT FAILED"
-def _scatter_into(self, src, dim, index):
-  out = unwrap(self).clone()
-  slices = [slice(None)] * out.ndim
-  slices[dim] = index
-  out[slices] = unwrap(src).cast(out.dtype)  # torch casts src to self's dtype, tinygrad setitem demands they already match
-  return wrap(out)
-
-@torch.library.impl("aten::slice_scatter", "privateuseone")
-def slice_scatter(self, src, dim=0, start=None, end=None, step=1): return _scatter_into(self, src, dim, slice(start, end, step))
-
-@torch.library.impl("aten::select_scatter", "privateuseone")
-def select_scatter(self, src, dim, index): return _scatter_into(self, src, dim, index)
-
-@torch.library.impl("aten::diagonal_scatter", "privateuseone")
-def diagonal_scatter(self, src, offset=0, dim1=0, dim2=1):
-  # a diagonal is not one axis, so scatter through the flat indices it picks out
-  base, out = unwrap(self), unwrap(self).clone().reshape(-1)
-  idx = Tensor.arange(base.numel(), dtype=dtypes.int32).reshape(base.shape).diagonal(offset, dim1, dim2).reshape(-1)
-  out[idx] = unwrap(src).cast(base.dtype).reshape(-1)
-  return wrap(out.reshape(base.shape))
-
-# the functional copy_. without an impl the fallback segfaults on a tensor with no storage
-@torch.library.impl("aten::copy", "privateuseone")
-def copy(self, src, non_blocking=False):
-  dest = unwrap(self)
-  return wrap(unwrap(src).cast(dest.dtype).to(dest.device).expand(dest.shape))
-
 @torch.library.impl("aten::slice_backward", "privateuseone")
 def slice_backward(grad_out, input_sizes, dim, start, end, step):
   grad_input = Tensor.zeros(input_sizes).contiguous()
@@ -341,9 +341,7 @@ for dim in [1, 2, 3]:
     torch.library.impl(f"aten::{pad_type}_pad{dim}d", "privateuseone")(functools.partial(pad_forward, mode=mode))
     torch.library.impl(f"aten::{pad_type}_pad{dim}d_backward", "privateuseone")(functools.partial(pad_backward, mode=mode))
 
-# the schemas are all positional: (self, output_size, align_corners, *scales) for linear, (self, output_size, *scales) for nearest.
-def upsample(self, size, *args, mode=None):
-  return wrap(Tensor.interpolate(unwrap(self), size, mode=mode, align_corners=args[0] if mode == "linear" else False))
+def upsample(self, size, align_corners=False, mode=None): return wrap(Tensor.interpolate(unwrap(self), size, mode=mode, align_corners=align_corners))
 for i,pre in enumerate(["", "bi", "tri"]):
   torch.library.impl(f"aten::upsample_{pre}linear{i+1}d", "privateuseone")(functools.partial(upsample, mode="linear"))
   torch.library.impl(f"aten::upsample_nearest{i+1}d", "privateuseone")(functools.partial(upsample, mode="nearest"))
@@ -415,7 +413,6 @@ def _linalg_svd(self, full_matrices=False):
 from torch._decomp import get_decompositions
 decomps = [
   aten.native_layer_norm_backward,
-  aten.native_group_norm_backward,
   aten.linalg_cross,
   aten.addmm,
   aten.addcmul,
@@ -450,20 +447,12 @@ decomps = [
   aten._softmax_backward_data, aten.embedding_dense_backward,
   aten.linalg_vector_norm,
   aten.binary_cross_entropy, aten.binary_cross_entropy_backward,
-  # the C++ mse/smooth_l1 kernels resize their out tensor, and a tiny tensor has no storage to resize
-  aten.mse_loss, aten.mse_loss_backward,
-  aten.smooth_l1_loss, aten.smooth_l1_loss_backward,
   aten.upsample_nearest2d.out,
-  # NOTE: only the "out" overload, the "vec" one is CompositeImplicitAutograd and overriding it loses the autograd kernel
-  aten.upsample_bicubic2d.out,
-  aten._adaptive_avg_pool2d,
   # activations
   aten.hardswish, aten.hardswish_backward,
   aten.hardtanh, aten.hardtanh_backward,
   aten.gelu, aten.gelu_backward,
-  # NOTE: no aten.logical_or here, its decomposition reaches aten.bitwise_or through a path that checks aliasing by
-  # reading storage, which a tiny tensor has none of. it gets a direct impl below instead
-  aten.logical_and, aten.logical_xor,
+  aten.logical_and,
   aten.randint,
   aten.eye,
   aten.hardsigmoid_backward,
@@ -506,7 +495,7 @@ simple_tensor_methods = [
   # reduce
   "all", "any", "argmax", "argmin", "cumsum", "cumprod",
   # complex
-  "linspace"]
+  "avg_pool2d", "linspace"]
 
 tiny_backend_out = {**{f"aten.{x}.out":getattr(Tensor,x) for x in simple_tensor_methods}, **{
   "aten.add.out": lambda input,other,alpha=1: input+alpha*other,
@@ -590,8 +579,8 @@ tiny_backend = {**{k:wrap_out(v) for k,v in tiny_backend_out.items()}, **{
   # inplace ops using replace for fusion
   "aten.zero_": lambda x: x.const_like(0),
   "aten.fill_.Scalar": lambda x, y: x.const_like(y),
-  "aten.add_.Tensor": lambda self, other, alpha=1: self + other * alpha,
-  "aten.add_.Scalar": lambda self, other, alpha=1: self + other * alpha,
+  "aten.add_.Tensor": lambda self, other, alpha=1.0: self + other * alpha,
+  "aten.add_.Scalar": lambda self, other, alpha=1.0: self + other * alpha,
   "aten.mul_.Tensor": lambda self, other: self * other,
   "aten.mul_.Scalar": lambda self, other: self * other,
   # relu doesn't have an out form?
@@ -624,9 +613,7 @@ tiny_backend = {**{k:wrap_out(v) for k,v in tiny_backend_out.items()}, **{
   # these don't work in out form, they have size 0
   "aten.abs": Tensor.abs,
   "aten.logical_not": Tensor.logical_not,
-  # compare against zero first: logical_* is bool-valued for any input dtype, while | is bitwise
-  "aten.logical_or": lambda x, y: (x != 0) | (y != 0),
-  "aten.logical_or_": lambda x, y: (x != 0) | (y != 0),
+  "aten.logical_or_": lambda x, y: x | y,
   "aten.multinomial": Tensor.multinomial,
   "aten.masked_fill_.Scalar": lambda self, mask, value: self.masked_fill(mask, value),
   "aten.masked_fill_.Tensor": lambda self, mask, value: self.masked_fill(mask, value),
@@ -635,7 +622,14 @@ tiny_backend = {**{k:wrap_out(v) for k,v in tiny_backend_out.items()}, **{
   "aten.masked_select": Tensor.masked_select,
   "aten.all": Tensor.all,
   "aten.sgn": Tensor.sign,
+  "aten.acos": Tensor.acos,
   "aten.any": Tensor.any,
+  "aten.bitwise_not": Tensor.bitwise_not,
+  "aten.argmax": Tensor.argmax,
+  "aten.argmin": Tensor.argmin,
+  "aten.asinh": Tensor.asinh,
+  "aten.mul": Tensor.mul,
+  "aten.atanh": Tensor.atanh,
   "aten.fill_.Tensor": lambda self, value: self.const_like(value.reshape(()).item()),
   "aten.flip": Tensor.flip,
   "aten.scatter_reduce.two": Tensor.scatter_reduce,
@@ -648,7 +642,8 @@ tiny_backend = {**{k:wrap_out(v) for k,v in tiny_backend_out.items()}, **{
     Tensor.linspace(start, stop, steps, **({"dtype": _from_torch_dtype(dtype)} if dtype is not None else {})),
   "aten.topk": Tensor.topk,
   "aten.constant_pad_nd": lambda self, padding, value=0.0: self.pad(padding, mode="constant", value=value).contiguous(),
-  "aten.cumsum": lambda self, dim: self.cumsum(dim),
+  # TODO: input contiguous is needed to prevent CFGContext circular dependency assertion for shapes >512 (see test_cumsum_arange_large)
+  "aten.cumsum": lambda self, dim: self.contiguous().cumsum(dim),
   "aten.logsumexp": lambda self, axis, keepdim=False: self.logsumexp(axis[0], keepdim=keepdim),
   "aten.roll": Tensor.roll,
   "aten.logcumsumexp": Tensor.logcumsumexp,
@@ -657,7 +652,6 @@ tiny_backend = {**{k:wrap_out(v) for k,v in tiny_backend_out.items()}, **{
     self.ones_like(**{k: v for k, v in {"dtype": _from_torch_dtype(dtype) if dtype else None,
                                         "device": _from_torch_device(device) if device else None}.items() if v is not None}),
   "aten.max.dim": lambda self, dim, keepdim=False: (self.max(dim, keepdim), self.argmax(dim, keepdim).cast(dtype=dtypes.int64)),
-  "aten.min.dim": lambda self, dim, keepdim=False: (self.min(dim, keepdim), self.argmin(dim, keepdim).cast(dtype=dtypes.int64)),
   "aten.cummax": lambda self, dim: ((r := self.cummax(dim))[0], r[1].cast(dtypes.int64)),
   "aten.cummin": lambda self, dim: ((r := self.cummin(dim))[0], r[1].cast(dtypes.int64)),
   "aten.nonzero": Tensor.nonzero,

extra/torch_backend/test.py

@@ -166,15 +166,6 @@ class TestTorchBackend(unittest.TestCase):
     expected = np.array([[1.5, 5.2, 9.0], [13.2, 17.1, 18.4]], dtype=np.float32)
     np.testing.assert_equal(y3.cpu().numpy(), expected)
 
-  def test_argmax_argmin(self):
-    a = torch.arange(12, dtype=torch.float32, device=device).reshape(3, 4)
-    c = a.cpu()
-    for got, want in [(a.argmax(), c.argmax()), (a.argmin(0), c.argmin(0)), (a.argmax(1, keepdim=True), c.argmax(1, keepdim=True)),
-                      (torch.min(a, 1).indices, torch.min(c, 1).indices), (torch.max(a, 1).indices, torch.max(c, 1).indices),
-                      (torch.min(a, 1).values, torch.min(c, 1).values), (torch.min(a, 1, keepdim=True).indices, torch.min(c, 1, keepdim=True).indices)]:
-      self.assertEqual(got.dtype, want.dtype)  # torch's arg reduces are int64, tinygrad's are int32
-      np.testing.assert_equal(got.cpu().numpy(), want.numpy())
-
   def test_isfinite(self):
     a = torch.ones(4, device=device)
     np.testing.assert_equal(torch.isfinite(a).cpu().numpy(), [True, True, True, True])
@@ -382,22 +373,6 @@ class TestTorchBackend(unittest.TestCase):
     for bwd_eps in [1e-5, 0.3]:
       for got, want in zip(run(device, bwd_eps), run("cpu", bwd_eps)): np.testing.assert_allclose(got, want, atol=1e-4, rtol=1e-3)
 
-  def test_groupnorm_backward(self):
-    def run(dev):
-      x = torch.arange(24., device=dev).reshape(2, 4, 3).requires_grad_()
-      w = torch.linspace(0.5, 2.0, 4).to(dev).requires_grad_()
-      torch.nn.functional.group_norm(x, 2, w, torch.zeros(4, device=dev)).square().sum().backward()
-      return x.grad.cpu().numpy(), w.grad.cpu().numpy()
-    for got, want in zip(run(device), run("cpu")): np.testing.assert_allclose(got, want, atol=1e-4, rtol=1e-3)
-
-  def test_mse_smooth_l1_loss_backward(self):
-    def run(dev, loss):
-      x = torch.arange(4., device=dev).requires_grad_()
-      loss(x, torch.ones(4, device=dev)).backward()
-      return x.grad.cpu().numpy()
-    for loss in [torch.nn.functional.mse_loss, torch.nn.functional.smooth_l1_loss]:
-      np.testing.assert_allclose(run(device, loss), run("cpu", loss), atol=1e-6)
-
   def test_batchnorm_unsqueeze(self):
     bn = torch.nn.BatchNorm2d(4).to(device)
     x = torch.randn(8, 4, 3, 3, device=device)
@@ -821,86 +796,6 @@ class TestTorchBackend(unittest.TestCase):
     np.testing.assert_allclose(w_tiny.grad.cpu().numpy(), w_cpu.grad.numpy(), atol=1e-4, rtol=1e-3)
     np.testing.assert_allclose(b_tiny.grad.cpu().numpy(), b_cpu.grad.numpy(), atol=1e-4, rtol=1e-3)
 
-  def test_write_through_detach_of_unrealized(self):
-    a = torch.empty(4, device=device)
-    a.detach().fill_(3)
-    np.testing.assert_equal(a.cpu().numpy(), [3, 3, 3, 3])
-
-  def test_square_transpose_inplace(self):
-    # a same-shape transpose is not a reshape: writing the transposed values straight back would scramble the base
-    a = torch.tensor([[0., 1., 2.], [3., 4., 5.], [6., 7., 8.]], device=device)
-    a.transpose(0, 1).add_(100)
-    np.testing.assert_equal(a.cpu().numpy(), [[100., 101., 102.], [103., 104., 105.], [106., 107., 108.]])
-
-  def test_interpolate(self):
-    a = torch.arange(4, dtype=torch.float32, device=device).reshape(1, 1, 2, 2)
-    nearest = torch.nn.functional.interpolate(a, scale_factor=2.0)
-    np.testing.assert_equal(nearest.cpu().numpy()[0, 0], [[0, 0, 1, 1], [0, 0, 1, 1], [2, 2, 3, 3], [2, 2, 3, 3]])
-    linear = torch.nn.functional.interpolate(a, size=(4, 4), mode="bilinear", align_corners=False)
-    ref = torch.nn.functional.interpolate(a.cpu(), size=(4, 4), mode="bilinear", align_corners=False)
-    np.testing.assert_allclose(linear.cpu().numpy(), ref.numpy(), rtol=1e-5)
-
-  def test_interpolate_bicubic_area(self):
-    a = torch.arange(32, dtype=torch.float32, device=device).reshape(1, 2, 4, 4)
-    for mode, scale in [("bicubic", 2.0), ("area", 0.5)]:
-      ref = torch.nn.functional.interpolate(a.cpu(), scale_factor=scale, mode=mode)
-      np.testing.assert_allclose(torch.nn.functional.interpolate(a, scale_factor=scale, mode=mode).cpu().numpy(), ref.numpy(), atol=1e-4)
-
-  @unittest.expectedFailure
-  def test_interpolate_bicubic_backward(self):
-    # the forward comes from a decomposition, but aten::upsample_bicubic2d_backward has none (nor does
-    # aten::_adaptive_avg_pool2d_backward, for area), so training through these modes needs a real kernel
-    x = torch.arange(32., dtype=torch.float32, device=device).reshape(1, 2, 4, 4).requires_grad_()
-    torch.nn.functional.interpolate(x, scale_factor=2.0, mode="bicubic").sum().backward()
-
-  @unittest.expectedFailure
-  def test_interpolate_inexact_scale(self):
-    # torch forwards the raw scale_factor, Tensor.interpolate recomputes it from output_size, and they disagree here
-    a = torch.arange(6, dtype=torch.float32, device=device).reshape(1, 1, 2, 3)
-    tiny = torch.nn.functional.interpolate(a, scale_factor=2.5, mode="bilinear")
-    ref = torch.nn.functional.interpolate(a.cpu(), scale_factor=2.5, mode="bilinear")
-    np.testing.assert_allclose(tiny.cpu().numpy(), ref.numpy(), rtol=1e-5)
-
-  def test_logical_or_xor(self):
-    a = torch.tensor([True, True, False, False], device=device)
-    b = torch.tensor([True, False, True, False], device=device)
-    np.testing.assert_equal(torch.logical_or(a, b).cpu().numpy(), [True, True, True, False])
-    np.testing.assert_equal(torch.logical_xor(a, b).cpu().numpy(), [False, True, True, False])
-    # bool-valued whatever the input dtype, so this is not | and ^
-    i, j = torch.tensor([2, 0, 5, 0], device=device), torch.tensor([0, 0, 1, 1], device=device)
-    np.testing.assert_equal(torch.logical_or(i, j).cpu().numpy(), [True, False, True, True])
-    np.testing.assert_equal(torch.logical_xor(i, j).cpu().numpy(), [True, False, False, True])
-
-  def test_slice_scatter(self):
-    # the scatters are functional: they return a new tensor and must leave the one they were given alone
-    a = torch.arange(12, dtype=torch.float32, device=device).reshape(3, 4)
-    out = torch.slice_scatter(a, torch.ones(1, 4, device=device), 0, 0, 1)
-    np.testing.assert_equal(out.cpu().numpy(), [[1, 1, 1, 1], [4, 5, 6, 7], [8, 9, 10, 11]])
-    np.testing.assert_equal(a.cpu().numpy(), np.arange(12, dtype=np.float32).reshape(3, 4))
-
-  def test_slice_scatter_casts_src(self):
-    a = torch.zeros(3, 4, device=device)
-    out = torch.slice_scatter(a, torch.ones(1, 4, dtype=torch.int32, device=device), 0, 0, 1)
-    self.assertEqual(out.dtype, torch.float32)
-    np.testing.assert_equal(out.cpu().numpy()[0], np.ones(4, dtype=np.float32))
-
-  def test_select_scatter(self):
-    a = torch.arange(12, dtype=torch.float32, device=device).reshape(3, 4)
-    out = torch.select_scatter(a, torch.ones(4, device=device), 0, 1)
-    np.testing.assert_equal(out.cpu().numpy(), [[0, 1, 2, 3], [1, 1, 1, 1], [8, 9, 10, 11]])
-
-  def test_diagonal_scatter(self):
-    a = torch.zeros(3, 3, device=device)
-    out = torch.diagonal_scatter(a, torch.arange(3, dtype=torch.float32, device=device))
-    np.testing.assert_equal(out.cpu().numpy(), np.diag([0., 1., 2.]))
-    np.testing.assert_equal(a.cpu().numpy(), np.zeros((3, 3), dtype=np.float32))
-
-  def test_copy_functional(self):
-    # without an impl this segfaults rather than fails: a regression here takes the whole run down
-    a = torch.arange(4, dtype=torch.float32, device=device)
-    out = torch.ops.aten.copy(a, torch.zeros(4, device=device))
-    np.testing.assert_equal(out.cpu().numpy(), [0., 0., 0., 0.])
-    np.testing.assert_equal(a.cpu().numpy(), [0., 1., 2., 3.])
 
 from tinygrad import Tensor
 class TestBackendHelpers(unittest.TestCase):

test/backend/test_const_folding.py

@@ -188,6 +188,7 @@ class TestTautologicalCompare(unittest.TestCase):
     np.testing.assert_equal((Tensor(True) < Tensor(False)).numpy(), False)
     np.testing.assert_equal((Tensor(True) < Tensor(True)).numpy(), False)
 
+  @unittest.skipIf(Device.DEFAULT == "WEBGPU", "WEBGPU doesn't support NaN comparison correctly")
   def test_a_eq_a(self):
     # self eq is always true for int or bool
     a = Tensor([1, 2, 3])

test/backend/test_dtype.py

@@ -340,9 +340,6 @@ class TestUint64DType(TestDType):
   DTYPE = dtypes.uint64
   def test_uint64_load(self):
     assert Tensor(2**64 - 1, dtype=dtypes.uint64).numpy() == 2**64 - 1
-  @unittest.skipIf(dtypes.double not in supported_dtypes, "needs float64")
-  def test_uint64_cast_double(self):
-    assert Tensor([2**32 + 1], dtype=dtypes.uint64).cast(dtypes.double).numpy() == 2**32 + 1
 
 @unittest.skipIf(isinstance(Device[Device.DEFAULT].renderer, PTXRenderer), "PTX does indexing math with longs")
 class TestEmulatedUInt64DType(TestUint64DType):

test/backend/test_isel.py

@@ -7,7 +7,7 @@ from tinygrad.renderer.isa.x86 import X86Renderer, X86Ops
 from tinygrad.renderer.isa import IselContext
 
 # INDEX on a register value with a constant index extracts a single element (the old GEP)
-def lane(y:UOp, i:int) -> UOp: return y.index(UOp.const(i, dtypes.int), dtype=y.dtype)
+def lane(y:UOp, i:int) -> UOp: return y.index(UOp.const(i, dtypes.int), dtype=y.dtype.scalar())
 
 @unittest.skipUnless(isinstance(Device[Device.DEFAULT].renderer, X86Renderer), "only x86")
 class TestIselX86(unittest.TestCase):

test/backend/test_quantize_onnx.py

@@ -82,7 +82,7 @@ class TestQuantizeOnnxCPU(unittest.TestCase):
       linear = run_onnx({"input":inp})["output"].schedule_linear()
       prg = to_program(linear.src[-2].src[0], renderer=Device[Device.DEFAULT].renderer)
       daccs = [u for u in tuple(prg.src[1].src) if u.op is Ops.BUFFER and u.addrspace is AddrSpace.REG]
-      assert all(u.dtype is dtypes.int for u in daccs)
+      assert all(u.dtype.scalar() is dtypes.int for u in daccs)
 
 @unittest.skipIf(Device.DEFAULT != "DSP", "only tests for DSP")
 class TestQuantizeOnnx(unittest.TestCase):

test/backend/test_tensor.py

@@ -653,19 +653,9 @@ class TestZeroShapeTensor(unittest.TestCase):
     np.testing.assert_equal(Tensor([[1, 2]]).pad_to(2, 3).numpy(), [[1, 2, 0], [0, 0, 0]])
     np.testing.assert_equal(Tensor([[1, 2]]).pad_to(1, 3).numpy(), [[1, 2, 0]])
     np.testing.assert_equal(Tensor([[1, 2]]).pad_to(None, 3).numpy(), [[1, 2, 0]])
-    np.testing.assert_equal(Tensor([1, 2]).pad_to(4, value=2).numpy(), [1, 2, 2, 2])
-    np.testing.assert_equal(Tensor([[1, 2]]).pad_to(2, 3, value=-1).numpy(), [[1, 2, -1], [-1, -1, -1]])
-    np.testing.assert_equal(Tensor([1, 2]).pad_to(None, value=5).numpy(), [1, 2])  # no-op pad ignores the fill
     with self.assertRaises(ValueError): Tensor([1, 2]).pad_to(2, 3)
     with self.assertRaises(ValueError): Tensor([[1, 2]]).pad_to(3)
 
-  def test_max_shape(self):
-    from tinygrad import UOp
-    t = Tensor.empty(2, UOp.variable('v', 1, 32), 4)
-    self.assertEqual(t.max_shape, (2, 32, 4))
-    self.assertEqual(t.max_numel(), 2*32*4)
-    self.assertEqual(Tensor.empty(2, 3).max_shape, (2, 3))
-
   def test_shrink_into_zero(self):
     t = Tensor.rand(3, 4).realize()
     assert t.shrink((None, (2, 2))).realize().shape == (3, 0)

test/device/test_hcq2.py

@@ -10,13 +10,5 @@ class TestHCQ2(unittest.TestCase):
     with patch.object(Device[Device.DEFAULT], "has_copy_queue", False):
       np.testing.assert_equal(Tensor(np.arange(61, dtype=np.float32)).to(Device.DEFAULT).contiguous().realize().numpy(), np.arange(61))
 
-  def test_overlapping_device_tuples(self):
-    # an op on a wide device tuple followed by an op on an overlapping smaller tuple used to MMU-fault the smaller one
-    d4, d2 = tuple(f"{Device.DEFAULT}:{i}" for i in range(4)), tuple(f"{Device.DEFAULT}:{i}" for i in range(2))
-    ref = Tensor.arange(16).contiguous().realize()
-    Tensor(ref.uop.copy_to_device(d4)).realize()
-    out = Tensor.ones(8).shard(d2, axis=0).contiguous().realize()
-    np.testing.assert_equal(out.numpy(), np.ones(8))
-
 if __name__ == "__main__":
   unittest.main()

test/external/external_uop_gc.py

@@ -44,7 +44,7 @@ def realized_matmul():
   z = y.matmul(x)
   Tensor.realize(z)
 def realized_gradient():
-  x = Tensor.eye(3).clone()
+  x = Tensor.eye(3)
   y = Tensor([[2.0,0,-2.0]])
   z = y.matmul(x).sum()
   z.backward()

test/helpers.py

@@ -86,9 +86,7 @@ def assert_jit_cache_len(fxn, expected_len):
   if linear is None or not linear.src:
     if expected_len != 0: raise KernelCountException(expected_len, 0)
     return
-  if expected_len and all(call_is_hcq(call) for call in linear.src): # HCQ2: one batch submitter, or fence + reset + merged calls + finalizer
-    from tinygrad.runtime.support.hcq2 import HCQ_RUNTIME_DEV
-    expected_len = 1 if HCQ_RUNTIME_DEV.value == "CPU" else 4
+  if expected_len and all(call_is_hcq(call) for call in linear.src): expected_len = 4 # HCQ2: fence + reset + merged same-queue calls + finalizer
   if call_is_graph(linear.src[0]):
     if len(linear.src) != 1: raise KernelCountException(1, len(linear.src))
     inner = linear.src[0].src[0].src[0]  # LINEAR UOp inside CUSTOM_FUNCTION

test/null/test_dtype_spec.py

@@ -51,6 +51,10 @@ class TestHelpers(unittest.TestCase):
     assert dtypes.is_float(dtypes.fp8e4m3)
     assert dtypes.is_float(dtypes.fp8e5m2)
 
+  @given(strat.sampled_from([d for d in DTYPES_DICT.values() if dtypes.is_float(d) or dtypes.is_int(d)]))
+  def test_scalar(self, dtype):
+    assert dtype.scalar() == dtype
+
   def test_from_py(self):
     assert dtypes.from_py(True) == dtypes.bool
     assert dtypes.from_py(Invalid) == dtypes.bool

test/null/test_tensor.py

@@ -69,7 +69,7 @@ class TestIdxUpcast(unittest.TestCase):
     if not isinstance(Device[Device.DEFAULT].renderer, (PTXRenderer, NIRRenderer)):
       assert idx.op is Ops.INDEX
       idx_val = idx.src[1]
-      self.assertFalse(idx_val.overflows(idx_val.dtype))
+      self.assertFalse(idx_val.overflows(idx_val.dtype.scalar()))
 
   # use expand to generate kernel that uses large idx
   def do_op_then_assert(self, dtype: DType, dim1, dim2, dim3):

test/opt/test_gen_float4.py

@@ -10,12 +10,12 @@ from test.helpers import replace_opts
 class TestFloat4(unittest.TestCase):
   @staticmethod
   def count_float4(uops: list[UOp], n=4):
-    return (len([uop for uop in uops if uop.op is Ops.LOAD and uop.dtype == dtypes.float and uop.shape == (4,)]),
-            len([uop for uop in uops if uop.op is Ops.STORE and uop.src[1].dtype == dtypes.float and uop.shape == (4,)]))
+    return (len([uop for uop in uops if uop.op is Ops.LOAD and uop.dtype.scalar() == dtypes.float and uop.shape == (4,)]),
+            len([uop for uop in uops if uop.op is Ops.STORE and uop.src[1].dtype.scalar() == dtypes.float and uop.shape == (4,)]))
   @staticmethod
   def count_half4(uops: list[UOp]):
-    return (len([uop for uop in uops if uop.op is Ops.LOAD and uop.dtype == dtypes.half and uop.shape == (4,)]),
-            len([uop for uop in uops if uop.op is Ops.STORE and uop.src[1].dtype == dtypes.half and uop.shape == (4,)]))
+    return (len([uop for uop in uops if uop.op is Ops.LOAD and uop.dtype.scalar() == dtypes.half and uop.shape == (4,)]),
+            len([uop for uop in uops if uop.op is Ops.STORE and uop.src[1].dtype.scalar() == dtypes.half and uop.shape == (4,)]))
 
   def test_float4_basic(self):
     a = Tensor.empty(2, 8).realize()

test/unit/test_allreduce.py

@@ -64,7 +64,7 @@ class TestAllreduceCast(unittest.TestCase):
     with Context(ALLREDUCE_CAST=allreduce_cast, RING=0, SCACHE=0):
       t = Tensor.empty(4, 4, dtype=dtype).shard(ds, axis=0)
       linear = t.sum(0).linear_with_vars()[0]
-      return {si.src[1].buffer.dtype for si in linear.src if si.src[0].op is Ops.COPY}
+      return {si.src[1].buffer.dtype.scalar() for si in linear.src if si.src[0].op is Ops.COPY}
 
   def test_allreduce_cast_bf16(self):
     # with ALLREDUCE_CAST, allreduce copies stay in bfloat16 instead of promoting to float32

tinygrad/codegen/decomp/dtype.py

@@ -33,8 +33,7 @@ def l2i(op: Ops, dt: DType, *uops:UOp):
       return (lo:=uops[0].cast(l2i_dt[dt])), (uops[0] / 2**32).cast(l2i_dt[dt]) - ((uops[0] < 0) & lo.ne(0))
     case Ops.CAST if dt in dtypes.floats:
       small = (a1.eq(0) & (a0 >= 0)) | (a1.eq(-1) & (a0 < 0))
-      cdt = dt if dt == dtypes.float64 else dtypes.float32
-      return small.where(a0.cast(dt), ((a1.cast(cdt) * (2**32)) + a0.bitcast(dtypes.uint).cast(cdt)).cast(dt))
+      return small.where(a0.cast(dt), ((a1.cast(dtypes.float32) * (2**32)) + a0.bitcast(dtypes.uint).cast(dtypes.float32)).cast(dt))
     case Ops.CAST: return a0.bitcast(dtypes.uint).cast(dt)
     case Ops.BITCAST: return a0.bitcast(dt), a1.bitcast(dt)
     case Ops.SHL:

tinygrad/device.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 from dataclasses import dataclass, replace
 from collections import defaultdict
-from typing import Any, Callable, Generic, TypeVar, Iterator, Generator, Self, TYPE_CHECKING
+from typing import Any, Generic, TypeVar, Iterator, Generator, Self, TYPE_CHECKING
 import importlib, inspect, functools, pathlib, os, contextlib, re, atexit, pickle, decimal
 from tinygrad.helpers import LRU, getenv, diskcache_get, diskcache_put, DEBUG, GlobalCounters, PROFILE, temp, colored
 from tinygrad.helpers import Context, CCACHE, ALLOW_DEVICE_USAGE, MAX_BUFFER_SIZE, cpu_events, ProfileEvent, ProfilePointEvent, suppress_finalizing
@@ -103,7 +103,7 @@ class Buffer:
   def __init__(self, device:str, size:int, dtype:DType, opaque:Any=None, options:BufferSpec|None=None,
                initial_value:bytes|pickle.PickleBuffer|None=None, uop_refcount=0, base:Buffer|None=None, offset:int=0, preallocate=False):
     assert isinstance(dtype, DType)
-    self.device, self.size, self.dtype, self.options, self.offset, self.allocated_views = Device.canonicalize(device), size, dtype, options, offset, 0
+    self.device, self.size, self.dtype, self.options, self.offset, self.allocated_views = device, size, dtype, options, offset, 0
     self._bufs: dict[str, Any] = {}
     if base is None:
       assert offset == 0, "base buffers can't have offset"
@@ -116,7 +116,7 @@ class Buffer:
         if isinstance(initial_value, pickle.PickleBuffer): initial_value.release()
     else:
       assert base._base is None, "base can't have a base"
-      assert self.device == base.device, "base must have the same device"
+      assert device == base.device, "base must have the same device"
       self._base = base
     if preallocate: self.allocate()
   @property
@@ -133,7 +133,7 @@ class Buffer:
   # check if the underlying buffer is allocated, possibly from the base object
   def is_allocated(self) -> bool: return self.base.is_allocated() if self._base is not None else self.device in self._bufs
   def get_buf(self, device: str) -> Any:
-    if (device:=Device.canonicalize(device)) not in self._bufs:
+    if device not in self._bufs:
       allocator = Device[device].allocator
       if device == self.device: self.ensure_allocated()
       elif self._base is not None: self._bufs[device] = allocator._offset(self._base.get_buf(device), self.nbytes, self.offset)
@@ -331,18 +331,17 @@ class Program(Generic[DeviceType]):
                wait=False) -> float|None: pass
 
 class Compiled:
-  ifaces:list[Callable] = []
   profile_events:list[ProfileEvent] = [ProfileDeviceEvent("CPU")] # NOTE: CPU is the default device.
 
-  has_copy_queue:bool = True
-
   pm_lower:Any = None
   pm_bufferize:Any = None
 
+  has_copy_queue:bool = True
+
   def __init__(self, device:str, allocator:Allocator, renderers:list[type[Renderer]], runtime:type[Program[Self]]|None, graph=None, arch=None):
     from tinygrad.renderer import Renderer
     self.device, self.allocator, self.runtime_t, self.graph, self.renderers = device, allocator, runtime, graph, renderers or [Renderer]
-    self.device_id, self.arch = (int(idx) if ":" in device and (idx:=device.split(":")[1]).isdigit() else 0), arch
+    self.arch = arch
     self.cached_renderer:dict[Any, Renderer] = {}
 
   @property
@@ -365,21 +364,11 @@ class Compiled:
     return select_first_inited(select_by_name(self.renderers, self._renderer_name, t.renderer, f"{self.device} has no renderer {t.renderer!r}"),
                                f"No renderer for {self.device} is available", self.cached_renderer, t)
 
-  def _select_iface(self, device:str):
-    self.device_id = int(device.split(":")[1]) if ":" in device else 0
-    assert (v:=getenv(k:=f'{type(self).__name__[:-6].upper()}_IFACE', "")) == "",  \
-      f"{k}={v} is deprecated, use DEV={replace(DEV.target(type(self).__name__[:-6]), interface=v)} instead"
-    t = DEV.target(dev:=type(self).__name__[:-6])
-    filtered = select_by_name(self.ifaces, lambda i: i.__name__[:-5], t.interface, f"{dev} has no interface {t.interface!r}")
-    filtered = [i for i in filtered if t.interface.startswith("MOCK") or not i.__name__[:-5].startswith("MOCK")] # never fallback to mock ifaces
-    return select_first_inited([functools.partial(iface, self, self.device_id) for iface in filtered],
-                               f"No interface for {dev}:{self.device_id} is available")
-
   def count(self) -> int:
     """
     Returns the number of physical accelerators available to the runtime.
     """
-    return self.iface.count if hasattr(self, 'iface') else 1
+    return 1
 
   def synchronize(self):
     """
@@ -397,7 +386,7 @@ class Compiled:
     """
     Called at the end of process lifetime to allow the device to finalize.
     """
-    if hasattr(self, 'iface') and hasattr(self.iface, 'device_fini'): self.iface.device_fini()
+    # override this in your device implementation
 
 if PROFILE:
   @atexit.register
@@ -419,7 +408,7 @@ def enumerate_devices_str() -> Generator[str, None, None]:
     ren_results, iface_results = [], []
     try:
       d = Device[device]
-      for iface in [i for i in d.ifaces if not i.__name__.startswith("MOCK")]:
+      for iface in [i for i in getattr(d, 'ifaces', []) if not i.__name__.startswith("MOCK")]:
         try:
           name = iface.__name__[:-5]
           default_text, count = ("(default)", d.count()) if type(d.iface) is iface else (f"(DEV={name}+{device} to make default)", iface(d, 0).count) # type: ignore

tinygrad/dtype.py

@@ -66,6 +66,7 @@ class DType(metaclass=DTypeMetaClass):
   def __reduce__(self): return type(self), tuple(getattr(self, f.name) for f in fields(self))
   def __repr__(self): return f"dtypes.{INVERSE_DTYPES_DICT[self.name]}"
   def __lt__(self, o:DType): return (self.priority, self.bitsize, self.name, self.fmt) < (o.priority, o.bitsize, o.name, o.fmt)
+  def scalar(self) -> DType: return self
   @functools.cached_property
   def min(self):
     if dtypes.is_int(self): return 0 if dtypes.is_unsigned(self) else -2**(self.bitsize-1)

tinygrad/engine/jit.py

@@ -269,14 +269,10 @@ class _TinyJit(Generic[ReturnType]):
         big_linear, onetime_linear = prune_linear(big_linear, set(input_buf_uops))
         if DEBUG >= 1: print(f"pruned from {len(big_linear.src) + len(onetime_linear.src)} -> {len(big_linear.src)} kernels")
         run_linear(onetime_linear, var_vals)
-        del onetime_linear
 
       # hold all buffers reachable from live Tensors (e.g. lazy .grad created during capture), the memory planner can't suballocate those
       held_bufs = set(buffers) | {u for tref in list(all_tensors) if (t:=tref()) is not None for u in t.uop.toposort() if u.op is Ops.BUFFER}
       linear = jit_lower(big_linear, held_bufs, input_buf_uops)
-      # drop the pre-planning graph: it keeps the whole capture-time working set allocated (big_linear) or referenced (held_bufs).
-      # the planned linear only uses the arena/held buffers, so the intermediates must be freed before linking and first exec
-      del big_linear, held_bufs
       self.captured = CapturedJit(ret, linear, names, expected_input_info)
       ret = self.captured(input_buf_uops, var_vals)
     elif self.cnt >= 2:

tinygrad/engine/realize.py

@@ -3,10 +3,9 @@ from typing import cast, Iterator, Any, Sequence
 import time, random, itertools, math, contextlib, weakref, array
 from dataclasses import dataclass, replace, field
 from tinygrad.helpers import colored, DEBUG, GlobalCounters, ansilen, all_int, prod, flatten, Context, getenv, to_tuple
-from tinygrad.helpers import BEAM, size_to_str, time_to_str, VALIDATE_WITH_CPU, PROFILE, ProfilePointEvent, cpu_events
+from tinygrad.helpers import BEAM, size_to_str, time_to_str, VALIDATE_WITH_CPU, PROFILE, ProfilePointEvent, cpu_events, wait_cond
 from tinygrad.uop.ops import Ops, PatternMatcher, UOp, UPat, AxisType, sym_infer, graph_rewrite
 from tinygrad.device import Device, Buffer, MultiBuffer, ProfileGraphEntry
-from tinygrad.dtype import dtypes
 from tinygrad.renderer import Estimates
 from tinygrad.codegen import to_program
 from tinygrad.codegen.opt.postrange import args_from_ast
@@ -14,9 +13,7 @@ from tinygrad.codegen.opt.postrange import args_from_ast
 # **************** Helpers ****************
 
 def get_call_arg_uops(call:UOp) -> tuple[UOp, ...]: return tuple(s for s in call.src[1:] if not s.is_bound_var)
-def get_call_var_uops(call:UOp, prg:UOp) -> list[UOp]:
-  bound = {s.src[0].expr: s.src[1].src[1] for s in call.src[1:] if s.is_bound_var}
-  return [bound.get(v.expr, v) for v in prg.arg.vars]
+
 def get_call_outs_ins(call:UOp) -> tuple[tuple[int, ...], tuple[int, ...]]:
   ast = call.src[0]
   if ast.op is Ops.PROGRAM: return tuple(ast.arg.outs), tuple(ast.arg.ins)
@@ -169,10 +166,9 @@ def exec_copy(ctx:ExecContext, call:UOp, ast:UOp) -> float|None:
 
 def exec_kernel(ctx:ExecContext, call:UOp, ast:UOp) -> float|None:
   et = None
-  resolved = resolve_params(call, ctx.input_uops)
-  for device, (bufs, device_vars) in zip(to_tuple(call.src[1].device), unwrap_multi(call, [resolved[i] for i in ast.arg.globals])):
+  for device, (bufs, device_vars) in zip(to_tuple(call.src[1].device), unwrap_multi(call, resolve_params(call, ctx.input_uops))):
     var_vals = {**ctx.var_vals, **device_vars}
-    prg_bufs = [b.ensure_allocated() for b in bufs]
+    prg_bufs = [bufs[i].ensure_allocated() for i in ast.arg.globals]
     rt = get_runtime(device, ast, cache=ctx.cache)
     global_size, local_size = ast.arg.launch_dims(var_vals)
     with track_stats(ctx, call, device, prg_bufs, var_vals) as tm:
@@ -204,26 +200,28 @@ def exec_graph(ctx:ExecContext, call:UOp, ast:UOp) -> float|None:
   return t[0]
 
 def exec_hcq(ctx:ExecContext, call:UOp, ast:UOp) -> float|None:
-  dev = cast(Any, Device[(info:= call.arg.aux).device[0]])
-  addrs = [(b.bufs[j] if isinstance(b:=_resolve(ctx.input_uops[k], ctx.input_uops).buffer, MultiBuffer) else b).get_buf(dev_name).va_addr
-           for devs, idxs in info.input_idxs for j, dev_name in enumerate(devs) for k in idxs]
-  dev.rt_buffer._buf.cpu_view().view(offset=(base:=dev.rt_allocator.alloc(len(addrs) * 8)), fmt='Q')[:len(addrs)] = array.array('Q', addrs)
+  if (info:=call.arg.aux).inputs is not None:
+    bufs = [_resolve(ctx.input_uops[i], ctx.input_uops).buffer for i in call.arg.aux.input_idxs]
+    table = call.src[1+info.inputs].buffer
+    for j,dev in enumerate(call.arg.aux.device):
+      addrs = array.array('Q', [(b.bufs[j] if isinstance(b, MultiBuffer) else b).get_buf(dev).va_addr for b in bufs])
+      mv = (table.bufs[j] if isinstance(table, MultiBuffer) else table).ensure_allocated()._buf.cpu_view().view(fmt='Q')
+      wait_cond(lambda: mv[0], value=0, timeout_ms=ctx.timeout or getenv("HCQDEV_WAIT_TIMEOUT_MS", 30000), msg=f"{dev} hang detected")
+      mv[:len(addrs)] = addrs
 
-  tables = [UOp.from_buffer(dev.rt_buffer.view(len(idxs), dtypes.uint64, base + j*len(idxs)*8), HCQ_RUNTIME_DEV.value)
-            for devs, idxs in info.input_idxs for j in range(len(devs))]
-  if info.inputs is not None: call = call.substitute({call.src[1+info.inputs]: UOp.mstack(*tables)})
-  exec_kernel(replace(ctx, update_stats=DEBUG>=3, var_vals={**ctx.var_vals, "hcq_inputs_ptr": dev.rt_buffer._buf.va_addr + base}), call, ast)
+  exec_kernel(replace(ctx, update_stats=DEBUG>=3), call, ast)
 
   tms = []
-  for devices, stat_call, prof in info.kernels:
+  for devices,name,estimates,prof in info.kernels:
     for device in devices:
       tm = None
       if prof:
-        (d:=cast(Any, Device[device])).prof_ents[prof[0]] = ProfileGraphEntry(device, stat_call.arg.name, *prof)
+        (d:=cast(Any, Device[device])).prof_ents[prof[0]] = ProfileGraphEntry(device, name, *prof)
         if ctx.wait:
           d.synchronize(timeout=ctx.timeout)
           st, en = (d.signal(x)._buf.cpu_view().view(fmt='Q')[0] for x in prof)
           tms.append(tm:=float(en-st)/d.timestamp_divider/1e6)
+      stat_call = call.replace(arg=replace(call.arg, name=name, aux=replace(info, estimates=estimates, kernels=())))
       with track_stats(ctx, stat_call, device, [], ctx.var_vals) as et: et[0] = tm
   return max(tms) if tms else None
 
@@ -264,7 +262,7 @@ pm_exec = PatternMatcher([
   (UPat(Ops.CALL, src=(UPat(Ops.CUSTOM_FUNCTION, arg="validate", name="ast"),), name="call", allow_any_len=True), exec_validate),
 ])
 
-if getenv("HCQ2"): from tinygrad.runtime.support.hcq2 import hcq_compile, hcq_link, HCQ_RUNTIME_DEV # noqa: E402 # down here, hcq2 imports realize
+if getenv("HCQ2"): from tinygrad.runtime.support.hcq2 import hcq_compile, hcq_link # noqa: E402 # down here, hcq2 imports the helpers above
 
 def compile_linear(linear:UOp, beam:int|None=None, validate=False, input_uops:list[UOp]|None=None, profile:bool|None=None) -> UOp:
   if validate: linear = graph_rewrite(linear, pm_validate, name="validate", walk=True)

tinygrad/mixin/gradient.py

@@ -33,7 +33,7 @@ def call_gradient(ctx:UOp, k:UOp, needed:set[int]) -> tuple[UOp|None, ...]:
   params = {x.arg.slot:x for x in fxn.toposort(enter_calls=False) if x.op == Ops.PARAM}
   grad_args = ctx.src
   root_grad = UOp(Ops.TUPLE, src=tuple(UOp(Ops.NOOP) if g.op is Ops.NOOP else
-    g if g.device is None else g.param_like(len(args)+i) for i,g in enumerate(grad_args)))
+    g if g.base.op is Ops.CONST else g.param_like(len(args)+i) for i,g in enumerate(grad_args)))
   grads = compute_gradient(fxn, root_grad, set(params.values()))
   # for precompiled calls, substitute forward outputs with params so intermediates aren't recomputed
   fwd_subs = {src: src.param_like(len(args)+len(grad_args)+i) for i, src in enumerate(fxn.src)} if k.arg.precompile else {}

tinygrad/mixin/movement.py

@@ -46,16 +46,6 @@ class MovementMixin:
     """
     return prod(self.shape)
 
-  @property
-  def max_shape(self) -> tuple[int, ...]:
-    """The shape with every symbolic dimension replaced by its maximum."""
-    from tinygrad.uop.ops import to_max_shape  # deferred: ops.py imports the mixins
-    return to_max_shape(self.shape)
-
-  def max_numel(self) -> int:
-    """The number of elements in `max_shape`."""
-    return prod(self.max_shape)
-
   def size(self, dim:int|None=None) -> sint|tuple[sint, ...]:
     """
     Returns the size of the tensor. If `dim` is specified, return the length along dimension `dim`. Otherwise return the shape of the tensor.

tinygrad/mixin/op.py

@@ -289,12 +289,6 @@ class OpMixin(ElementwiseMixin, ReduceMixin):
     if value == 0: return base
     return MovementMixin.pad(X.const_like(True, dtypes.bool), pads).where(base, value)
 
-  def pad_to(self, shape, *args, value:ConstType=0) -> Self:
-    # same mask trick as _pad_constant so the fill survives backends that realize PAD as 0-fill
-    ret = MovementMixin.pad_to(self, shape, *args)
-    if value == 0 or ret is self: return ret
-    return MovementMixin.pad_to(self.const_like(True, dtypes.bool), shape, *args).where(ret, value)
-
   def _pad_circular(self, pX:tuple[tuple[sint, sint], ...]) -> Self:
     # shrink first for negative pads, then wrap the non-negative remainder
     X = self.shrink(tuple((-smin(pB,0), smin(pA+sh,sh)) for (pB,pA),sh in zip(pX, self.shape)))

tinygrad/renderer/__init__.py

@@ -35,8 +35,8 @@ class Estimates:
         while len(buf.src) and buf.op is not Ops.PARAM: buf = buf.src[0]
         if buf.op is Ops.PARAM:
           # u.src[0] is INDEX, cap at buffer size for re-reads (e.g. matmul)
-          accessed = mem.get((buf, u.op), 0) + u.src[0].max_numel() * u.src[0].dtype.itemsize * mults
-          mem[(buf, u.op)] = smin(accessed, buf.max_numel() * buf.dtype.itemsize)
+          accessed = mem.get((buf, u.op), 0) + u.src[0].max_numel() * u.src[0].dtype.scalar().itemsize * mults
+          mem[(buf, u.op)] = smin(accessed, buf.max_numel() * buf.dtype.scalar().itemsize)
       if u.op is Ops.RANGE:
         mult_stack.append(mults)
         if u.dtype is not dtypes.void:  # unbounded loop, unknown trip count
@@ -47,9 +47,9 @@ class Estimates:
       elif u.op is Ops.SPECIAL: mults *= cast(sint, u.src[0].ssimplify()) # NOTE: we don't push to the mult_stack here, you can't end these
       elif u.op is Ops.PARAM and u.arg.addrspace == AddrSpace.ALU and u.expr == 'core_id': mults *= int(u.vmax) + 1
       elif u.op is Ops.LOAD and u.src[0].addrspace != AddrSpace.REG:
-        lds += u.max_numel() * u.dtype.itemsize * mults
+        lds += u.max_numel() * u.dtype.scalar().itemsize * mults
       elif u.op is Ops.STORE and u.src[0].addrspace != AddrSpace.REG:
-        lds += u.max_numel() * u.src[1].dtype.itemsize * mults
+        lds += u.max_numel() * u.src[1].dtype.scalar().itemsize * mults
       elif u.op in GroupOp.ALU and u not in excluded:
         flops += (mults * (2 if u.op is Ops.MULACC else 1)) * u.max_numel()
       elif u.op is Ops.WMMA and u not in excluded:

tinygrad/renderer/cstyle.py

@@ -107,11 +107,11 @@ def uops_to_dtypes(uops:list[UOp]) -> list[tuple[DType, int]]:
 
 def _wmma_name(u:UOp) -> str:
   # sanitize spaces in DType.name (int8 = "signed char")
-  return f"WMMA_{'_'.join(map(str, u.arg[0]))}_{u.arg[1].name}_{u.dtype.name}".replace(" ", "_")
+  return f"WMMA_{'_'.join(map(str, u.arg[0]))}_{u.arg[1].name}_{u.dtype.scalar().name}".replace(" ", "_")
 
 # (name, dims, dtype_in, dtype_out, device, threads, upcast_sizes)
 def wmma_args(uops:list[UOp]):
-  return dedup((_wmma_name(uop), uop.arg[0], uop.arg[1], uop.dtype, *(uop.arg[2:4]),
+  return dedup((_wmma_name(uop), uop.arg[0], uop.arg[1], uop.dtype.scalar(), *(uop.arg[2:4]),
                tuple(uop.src[i].shape[-1] for i in range(3)))
               for uop in uops if uop.op is Ops.WMMA)
 
@@ -182,8 +182,8 @@ class CStyleLanguage(Renderer):
     if addrspace in (AddrSpace.LOCAL, AddrSpace.GLOBAL) or override_ptr:
       suffix = "*"
     if sz > 1:
-      return prefix + self.type_map.get(dtype, dtype.name).replace(" ", "_") + str(sz) + suffix
-    return prefix + self.type_map.get(dtype, dtype.name) + suffix
+      return prefix + self.type_map.get(scalar:=dtype.scalar(), scalar.name).replace(" ", "_") + str(sz) + suffix
+    return prefix + self.type_map.get(scalar:=dtype.scalar(), scalar.name) + suffix
 
   def render_type(self, u:UOp): return self._render_dtype(u.dtype, u.max_numel(), u.addrspace, shape=u._shape)
   def render_access(self, u:UOp):
@@ -472,7 +472,7 @@ class CUDARenderer(CStyleLanguage):
 class NVCCRenderer(CUDARenderer):
   def __init__(self, target:Target): super().__init__(target, use_nvcc=True)
 
-def fp8_index(dtype: DType): return (dtypes.fp8e4m3, dtypes.fp8e5m2).index(dtype)
+def fp8_index(dtype: DType): return (dtypes.fp8e4m3, dtypes.fp8e5m2).index(dtype.scalar())
 def _ocml(op): return lambda x,dtype: f"__ocml_{op}_f{ {dtypes.half:16, dtypes.double:64}.get(dtype, 32)}({x})"
 
 class HIPRenderer(CStyleLanguage):
@@ -546,7 +546,7 @@ class HIPRenderer(CStyleLanguage):
       ockl = [(f"__ockl_get_{name}", "unsigned int", "size_t", "const") for name in ["local_id", "group_id", "local_size"]]
     ocml_ops = {Ops.EXP2: ("exp2", "pure"), Ops.LOG2: ("log2", "pure"), Ops.SQRT: ("sqrt", "const"), Ops.SIN: ("sin", ""), Ops.TRUNC: ("trunc", "")}
     ocml = [(f"__ocml_{ocml_ops[op][0]}_f{dt.bitsize}", dt.name, dt.name, ocml_ops[op][1])
-      for op, dt in dedup((u.op, u.dtype) for u in uops) if op in ocml_ops and dt in (dtypes.half, dtypes.float, dtypes.double)]
+      for op, dt in dedup((u.op, u.dtype.scalar()) for u in uops) if op in ocml_ops and dt in (dtypes.half, dtypes.float, dtypes.double)]
     if any(dt == dtypes.bfloat16 for dt, _ in used_dtypes):
       prefix.append(f"typedef {'__bf16' if self.is_cdna4(self.target.arch) else 'unsigned short'} hip_bfloat16;")
     if any(dt == dtypes.half for dt, _ in used_dtypes): prefix.append("#define half _Float16")

tinygrad/renderer/isa/x86.py

@@ -165,7 +165,7 @@ def scratch_buffer(elem_dt:DType, count:int, slot:int) -> UOp:
   return UOp.placeholder((count,), elem_dt, slot, AddrSpace.LOCAL)
 
 def gated_load(ctx, addr:UOp, alt:UOp, gate:UOp, x:UOp):
-  local = scratch_buffer(addr.src[0].dtype, x.max_numel(), next(ctx))
+  local = scratch_buffer(addr.src[0].dtype.scalar(), x.max_numel(), next(ctx))
   local_idx = local.index(UOp.const(0, dtypes.int32), dtype=dtypes.uint64)
   # the selected address is a 64bit value, the AFTER orders the load after the scratch store and carries the element dtype for the encoder
   sel = gate.where(addr.replace(dtype=dtypes.uint64), local_idx)
@@ -173,7 +173,7 @@ def gated_load(ctx, addr:UOp, alt:UOp, gate:UOp, x:UOp):
   return ptr.load(dtype=x.dtype)
 
 def gated_store(addr:UOp, gate:UOp, val:UOp):
-  local = scratch_buffer(addr.src[0].dtype, val.max_numel(), -1)
+  local = scratch_buffer(addr.src[0].dtype.scalar(), val.max_numel(), -1)
   sel = gate.where(addr.replace(dtype=dtypes.uint64), local.index(UOp.const(0, dtypes.int32), dtype=dtypes.uint64))
   return UOp(Ops.AFTER, addr.dtype, (sel,)).store(val)
 
@@ -237,7 +237,7 @@ def cmp(x:UOp) -> UOp:
   return x.ins(X86Ops.CMP, dtype=dtypes.void) if (i:=to_imm(x.src[1])) is None else x.ins(X86Ops.CMPi, dtype=dtypes.void, src=(x.src[0], i))
 def vcmp(x:UOp) -> UOp:
   v = imm(dtypes.uint8, {Ops.CMPLT: 1, Ops.CMPNE: 4, Ops.CMPEQ: 0}[x.op])
-  if x.dtype is dtypes.float32: return x.ins(X86Ops.VCMPSS if x.max_numel() == 1 else X86Ops.VCMPPS, src=x.src + (v,))
+  if x.dtype.scalar() is dtypes.float32: return x.ins(X86Ops.VCMPSS if x.max_numel() == 1 else X86Ops.VCMPPS, src=x.src + (v,))
   return x.ins(X86Ops.VCMPSD if x.max_numel() == 1 else X86Ops.VCMPPD, src=x.src + (v,))
 
 # vinsertps xmm2, xmm0, xmm1, imm
@@ -252,7 +252,7 @@ def vinsertps(x:UOp) -> UOp:
 # vpinsq xmm2, xmm0, rax, imm
 # inserts element in rax into any position in xmm0, result is written to xmm2 according to imm
 def vpins(x:UOp) -> UOp:
-  op = {1: X86Ops.VPINSRB, 2: X86Ops.VPINSRW, 4: X86Ops.VPINSRD, 8: X86Ops.VPINSRQ}[x.dtype.itemsize]
+  op = {1: X86Ops.VPINSRB, 2: X86Ops.VPINSRW, 4: X86Ops.VPINSRD, 8: X86Ops.VPINSRQ}[x.dtype.scalar().itemsize]
   return functools.reduce(lambda ret,i: x.ins(op, src=(ret, x.src[i], imm(dtypes.uint8, i))), range(len(x.src)), def_reg(x.dtype))
 
 # we don't call ctx.vreg on the srcs to avoid duplicates, a rewrite will assign the tuple of valid registers to a vreg

tinygrad/renderer/ptx.py

@@ -64,7 +64,7 @@ def render_wmma(ctx: "PTXRenderer", wmma: UOp):
 
   for src, regs in zip(wmma.src, ctx.wmma_r):
     for i, reg in enumerate(regs): # pack input and acc registers
-      if (elems_per_reg := 4 // src.dtype.itemsize) == 1: yield f"mov.b32 {reg}, {ctx.r[src][i]};"
+      if (elems_per_reg := 4 // src.dtype.scalar().itemsize) == 1: yield f"mov.b32 {reg}, {ctx.r[src][i]};"
       else: yield f"mov.b32 {reg}, {{{', '.join(ctx.r[src][i * elems_per_reg : (i+1) * elems_per_reg])}}};"
 
   dt_map_in, dt_map_out = {dtypes.float: "tf32", dtypes.half: "f16"}, {dtypes.float: "f32", dtypes.half: "f16"}
@@ -101,17 +101,17 @@ string_rewrite = PatternMatcher([
      if loc.addrspace == AddrSpace.REG else None),
   (UPat(Ops.STORE, src=(UPat((Ops.INDEX, Ops.SHRINK), name="loc"), UPat.var("var"))),
    lambda ctx, loc, var: f"st.{mem_type(loc)}" + \
-    f"{f'.v{cnt}' if ((cnt:=var.max_numel())>1) else ''}.{ctx.mem_types[var.dtype]} " + \
+    f"{f'.v{cnt}' if ((cnt:=var.max_numel())>1) else ''}.{ctx.mem_types[var.dtype.scalar()]} " + \
     f"[{ctx.r[loc]}+0], {('{' + ', '.join(ctx.r[var]) + '}') if var.max_numel() > 1 else ctx.r[var]};"),
   (UPat(Ops.LOAD, name="x", src=(UPat((Ops.INDEX, Ops.SHRINK), name="loc"), UPat.var("alt"), UPat.var("gate"))),
     lambda ctx, x, loc, alt, gate: flatten([
-    [f"mov.{ctx.mem_types[x.dtype]} {v}, {render_val(0, x.dtype)};" for v in ctx.r[x]],
-    [f"@{ctx.r[gate]} ld.{mem_type(loc)}.v{x.max_numel()}.{ctx.mem_types[x.dtype]} {{{', '.join(ctx.r[x])}}}, [{ctx.r[loc]}+0];"]
+    [f"mov.{ctx.mem_types[x.dtype.scalar()]} {v}, {render_val(0, x.dtype.scalar())};" for v in ctx.r[x]],
+    [f"@{ctx.r[gate]} ld.{mem_type(loc)}.v{x.max_numel()}.{ctx.mem_types[x.dtype.scalar()]} {{{', '.join(ctx.r[x])}}}, [{ctx.r[loc]}+0];"]
   ]) if alt.max_numel() > 1 else [
-    f"@{ctx.r[gate]} ld.{mem_type(loc)}.{ctx.mem_types[x.dtype]} {ctx.r[x]}, [{ctx.r[loc]}+0];",
-    f"@!{ctx.r[gate]} mov.b{ctx.types[x.dtype][1:]} {ctx.r[x]}, {ctx.r[alt]};"]),
+    f"@{ctx.r[gate]} ld.{mem_type(loc)}.{ctx.mem_types[x.dtype.scalar()]} {ctx.r[x]}, [{ctx.r[loc]}+0];",
+    f"@!{ctx.r[gate]} mov.b{ctx.types[x.dtype.scalar()][1:]} {ctx.r[x]}, {ctx.r[alt]};"]),
   (UPat(Ops.LOAD, name="x", src=(UPat((Ops.INDEX, Ops.SHRINK), name="loc"),)),
-    lambda ctx, x, loc: f"ld.{mem_type(loc)}.v{x.max_numel()}.{ctx.mem_types[x.dtype]} {{{', '.join(ctx.r[x])}}}, [{ctx.r[loc]}+0];" \
+    lambda ctx, x, loc: f"ld.{mem_type(loc)}.v{x.max_numel()}.{ctx.mem_types[x.dtype.scalar()]} {{{', '.join(ctx.r[x])}}}, [{ctx.r[loc]}+0];" \
      if x.max_numel() > 1 else f"ld.{mem_type(loc)}.{ctx.mem_types[x.dtype]} {ctx.r[x]}, [{ctx.r[loc]}+0];"),
   # simple
   (UPat(Ops.BUFFER, name="x"), lambda ctx, x: [] if x.addrspace == AddrSpace.REG else [
@@ -197,7 +197,7 @@ class PTXRenderer(Renderer):
         r[u] = [cast(str,r[x]) for x in u.src]
         continue
       if u.op is Ops.BUFFER and u.addrspace == AddrSpace.REG:
-        r[u] = [ssa("reg", u, self.types[u.dtype]) for _ in range(u.max_numel())]
+        r[u] = [ssa("reg", u, self.types[u.dtype.scalar()]) for _ in range(u.max_numel())]
         continue
       if u.op in {Ops.INDEX, Ops.SHRINK, Ops.LOAD} and u.src[0].addrspace in (AddrSpace.REG, AddrSpace.ALU):
         # on REG, INDEX/SHRINK pick the register (must be CONST) and LOAD is a noop
@@ -207,14 +207,14 @@ class PTXRenderer(Renderer):
         continue
       if u.op is Ops.SPECIAL: r[u] = "%" + u.arg
       elif u.op is Ops.LOAD:
-        r[u] = [ssa('val', dtype=self.types[u.dtype]) for _ in range(u.max_numel())] if u.max_numel() > 1 else ssa('val', u)
+        r[u] = [ssa('val', dtype=self.types[u.dtype.scalar()]) for _ in range(u.max_numel())] if u.max_numel() > 1 else ssa('val', u)
       elif u.op is Ops.PARAM: bufs.append((f"data{u.arg.slot}", u))
       elif u.op is Ops.WMMA:
         # registers for packing/unpacking input and acc
-        self.wmma_r = [[ssa("wmma_in", dtype="b32") for _ in range(0, len(r[u.src[0]]), 4 // u.src[0].dtype.itemsize)],
-                       [ssa("wmma_in", dtype="b32") for _ in range(0, len(r[u.src[1]]), 4 // u.src[0].dtype.itemsize)],
-                       [ssa("wmma_acc", dtype="b32") for _ in range(0, len(r[u.src[2]]), 4 // u.dtype.itemsize)]]
-        r[u] = [ssa("wmma", dtype=self.types[u.dtype]) for _ in range(u.max_numel())]
+        self.wmma_r = [[ssa("wmma_in", dtype="b32") for _ in range(0, len(r[u.src[0]]), 4 // u.src[0].dtype.scalar().itemsize)],
+                       [ssa("wmma_in", dtype="b32") for _ in range(0, len(r[u.src[1]]), 4 // u.src[0].dtype.scalar().itemsize)],
+                       [ssa("wmma_acc", dtype="b32") for _ in range(0, len(r[u.src[2]]), 4 // u.dtype.scalar().itemsize)]]
+        r[u] = [ssa("wmma", dtype=self.types[u.dtype.scalar()]) for _ in range(u.max_numel())]
       prefix, dtype = {Ops.CAST: ("cast", None), Ops.BITCAST: ("cast", None), Ops.END: ("pred", "pred"), Ops.RANGE: ("ridx", None),
         Ops.CONST: ("const", None), Ops.BUFFER: ("local", "u64"), Ops.INDEX: ("bidx", "u64"), Ops.SHRINK: ("bidx", "u64"),
         Ops.PARAM: ("dat", "u64" if u.addrspace is AddrSpace.GLOBAL else None), **{op: ("alu", None) for op in GroupOp.ALU}}.get(u.op, (None, None))

tinygrad/renderer/wgsl.py

@@ -50,9 +50,8 @@ wgsl_matcher = PatternMatcher([
   (UPat.store(UPat.var("b"), UPat.var("var"), name="s"), lambda b,var,s: packed_store(b,var) if is_packed(s) else None),
   (UPat.var("a") << UPat.var("b"),lambda a,b:(a.bitcast(dtypes.uint32)<<b.cast(dtypes.uint32)).bitcast(a.dtype) if b.dtype!=dtypes.uint32 else None),
   (UPat.var("x") >> UPat.var("y"), lambda x,y: UOp(Ops.SHR, x.dtype, (x,y.cast(dtypes.uint))) if y.dtype != dtypes.uint else None),
-  # fix nan check: 'a != a -> is_nan()'. the decomp rewrites (a != a).logical_not() to CMPEQ, so match both forms
-  (UPat.var("a", dtypes.floats) != UPat.var("a"), is_nan),
-  (UPat.var("a", dtypes.floats).alu(Ops.CMPEQ, UPat.var("a")), lambda a: is_nan(a).ne(True)),
+  # fix nan check: 'a != a -> is_nan()'
+  (UPat.var("a") != UPat.var("a"), is_nan),
   ])
 
 class WGSLRenderer(CStyleLanguage):

tinygrad/runtime/ops_amd.py

@@ -944,7 +944,9 @@ class AMDDevice(HCQCompiled):
   def is_usb(self) -> bool: return isinstance(self.iface, USBIface)
 
   def __init__(self, device:str=""):
-    self.iface = self._select_iface(device)
+    self.device_id = int(device.split(":")[1]) if ":" in device else 0
+
+    self.iface = self._select_iface()
 
     self.target:tuple[int, ...] = ((trgt:=self.iface.props['gfx_target_version']) // 10000, (trgt // 100) % 100, trgt % 100)
     self.arch = "gfx%d%x%x" % self.target

tinygrad/runtime/ops_cl.py

@@ -24,10 +24,10 @@ class CLCompiler(Compiler):
     super().__init__(f"compile_cl_{compile_key}")
   def compile(self, src:str) -> bytes:
     program = checked(cl.clCreateProgramWithSource(self.dev.context, 1, to_char_p_p([src.encode()]), None, status := ctypes.c_int32()), status)
-    build_status: int = cl.clBuildProgram(program, 1, self.dev.cl_dev, None, BP_CB(), None)
+    build_status: int = cl.clBuildProgram(program, 1, self.dev.device_id, None, BP_CB(), None)
     if build_status != 0:
-      cl.clGetProgramBuildInfo(program, self.dev.cl_dev, cl.CL_PROGRAM_BUILD_LOG, 0, None, log_size := ctypes.c_size_t())
-      cl.clGetProgramBuildInfo(program, self.dev.cl_dev, cl.CL_PROGRAM_BUILD_LOG,
+      cl.clGetProgramBuildInfo(program, self.dev.device_id, cl.CL_PROGRAM_BUILD_LOG, 0, None, log_size := ctypes.c_size_t())
+      cl.clGetProgramBuildInfo(program, self.dev.device_id, cl.CL_PROGRAM_BUILD_LOG,
                                log_size.value, mstr := ctypes.create_string_buffer(log_size.value), None)
       raise CompileError(f"OpenCL Compile Error\n\n{mstr.value.decode()}")
     check(cl.clGetProgramInfo(program, cl.CL_PROGRAM_BINARY_SIZES, ctypes.sizeof(ctypes.c_size_t), binary_sizes := (ctypes.c_size_t * 1)(), None))
@@ -39,11 +39,11 @@ class CLCompiler(Compiler):
 class CLProgram(Program['CLDevice']):
   def __init__(self, device:CLDevice, obj:TinyELF):
     self.dev, self.lib, self.signature = device, device.cl_compiler.compile_cached(obj.lib.decode()), obj.signature
-    self.program = checked(cl.clCreateProgramWithBinary(device.context, 1, device.cl_dev, (ctypes.c_size_t * 1)(len(self.lib)),
+    self.program = checked(cl.clCreateProgramWithBinary(device.context, 1, device.device_id, (ctypes.c_size_t * 1)(len(self.lib)),
                                                         to_char_p_p([self.lib], ctypes.c_ubyte), binary_status := ctypes.c_int32(),
                                                         errcode_ret := ctypes.c_int32()), errcode_ret)
     check(binary_status.value)
-    check(cl.clBuildProgram(self.program, 1, device.cl_dev, None, BP_CB(), None)) # NOTE: OSX requires this
+    check(cl.clBuildProgram(self.program, 1, device.device_id, None, BP_CB(), None)) # NOTE: OSX requires this
     self.kernel = checked(cl.clCreateKernel(self.program, obj.name.encode(), status := ctypes.c_int32()), status)
 
   def __del__(self):
@@ -101,17 +101,17 @@ class CLDevice(Compiled):
       CLDevice.device_ids = c.init_c_var((cl.cl_device_id * num_devices.value),
                                          lambda x: check(cl.clGetDeviceIDs(platform_ids[0], device_type, num_devices, x, None)))
 
-    self.cl_dev = CLDevice.device_ids[0 if ":" not in device else int(device.split(":")[1])]
-    self.device_name = (cl.clGetDeviceInfo(self.cl_dev, cl.CL_DEVICE_NAME, 256,
+    self.device_id = CLDevice.device_ids[0 if ":" not in device else int(device.split(":")[1])]
+    self.device_name = (cl.clGetDeviceInfo(self.device_id, cl.CL_DEVICE_NAME, 256,
                                            buf:=ctypes.create_string_buffer(256), None), buf.value.decode())[1]
-    self.driver_version = (cl.clGetDeviceInfo(self.cl_dev, cl.CL_DRIVER_VERSION, 256,
+    self.driver_version = (cl.clGetDeviceInfo(self.device_id, cl.CL_DRIVER_VERSION, 256,
                                               buf:=ctypes.create_string_buffer(256), None), buf.value.decode())[1]
     if DEBUG >= 1: print(f"CLDevice: opening {self.device_name} with version {self.driver_version}")
-    self.context = checked(cl.clCreateContext(None, 1, self.cl_dev, CC_CB(), None, status := ctypes.c_int32()), status)
-    self.queue = checked(cl.clCreateCommandQueue(self.context, self.cl_dev, cl.CL_QUEUE_PROFILING_ENABLE, status), status)
+    self.context = checked(cl.clCreateContext(None, 1, self.device_id, CC_CB(), None, status := ctypes.c_int32()), status)
+    self.queue = checked(cl.clCreateCommandQueue(self.context, self.device_id, cl.CL_QUEUE_PROFILING_ENABLE, status), status)
     self.pending_copyin: list[memoryview] = []
-    check(cl.clGetDeviceInfo(self.cl_dev, cl.CL_DEVICE_EXTENSIONS, 0, None, ctypes.byref(exts_len:=ctypes.c_size_t())))
-    self.device_exts = (cl.clGetDeviceInfo(self.cl_dev, cl.CL_DEVICE_EXTENSIONS, exts_len.value,
+    check(cl.clGetDeviceInfo(self.device_id, cl.CL_DEVICE_EXTENSIONS, 0, None, ctypes.byref(exts_len:=ctypes.c_size_t())))
+    self.device_exts = (cl.clGetDeviceInfo(self.device_id, cl.CL_DEVICE_EXTENSIONS, exts_len.value,
                                            ctypes.byref(buf := ctypes.create_string_buffer(exts_len.value)), None),
                                            ctypes.string_at(buf).decode().split())[1]
 
@@ -119,7 +119,7 @@ class CLDevice(Compiled):
 
     arch = ",".join(self.device_exts)
     if "cl_khr_image2d_from_buffer" in self.device_exts:
-      check(cl.clGetDeviceInfo(self.cl_dev, cl.CL_DEVICE_IMAGE_PITCH_ALIGNMENT, 4, ctypes.byref(ipa := ctypes.c_uint32()), None))
+      check(cl.clGetDeviceInfo(self.device_id, cl.CL_DEVICE_IMAGE_PITCH_ALIGNMENT, 4, ctypes.byref(ipa := ctypes.c_uint32()), None))
       arch += f",IMAGE_PITCH_ALIGNMENT={ipa.value}"
     super().__init__(device, CLAllocator(self), [OpenCLRenderer], CLProgram, arch=arch)
 

tinygrad/runtime/ops_cpu.py

@@ -13,7 +13,7 @@ from tinygrad.renderer.isa.x86 import X86Renderer
 from tinygrad.runtime.support.elf import jit_loader
 from tinygrad.runtime.autogen import libc
 from tinygrad.codegen import do_to_program
-from tinygrad.engine.realize import pm_flatten_linear, get_call_arg_uops, get_call_var_uops, get_runtime
+from tinygrad.engine.realize import pm_flatten_linear, get_call_arg_uops, get_runtime
 from tinygrad import UOp, dtypes
 from tinygrad.dtype import AddrSpace
 from tinygrad.uop.ops import KernelInfo, Ops, UPat, PatternMatcher, graph_rewrite
@@ -64,7 +64,7 @@ def cpu_cmd(devs:tuple[str, ...], prog, *args:UOp) -> UOp:
   return UOp(Ops.INS, dtypes.void, words + (UOp.const(0, dtypes.uint64),) * (CMD_SIZE - len(words)), arg="cmd")
 
 def cpu_exec(ctx:tuple[str, ...], call:UOp, prg:UOp) -> UOp:
-  args = [get_call_arg_uops(call)[i].getaddr(ctx) for i in prg.arg.globals] + [v.cast(dtypes.uint64) for v in get_call_var_uops(call, prg)]
+  args = [get_call_arg_uops(call)[i].getaddr(ctx) for i in prg.arg.globals] + [v.cast(dtypes.uint64) for v in prg.arg.vars]
   if (core:=prg.arg.runtimevars.get('core_id')) is None: return cpu_cmd(ctx, prg, *args)
 
   la = [cpu_cmd(ctx,prg,*args[:(cid:=(len(prg.arg.globals)+core))],UOp.const(t, dtypes.uint64),*args[cid+1:]) for t in range(prg.arg.global_size[0])]
@@ -99,11 +99,10 @@ def encode_queue(q:UOp) -> UOp:
   e = UOp.range(cnt, next(UOp.unique_num), dtype=dtypes.int, src=(cmdbuf, ring))
   copy = UOp.group(*[ring.index((base + e*CMD_SIZE + w) % ring_words).store(cmdbuf.index(e*CMD_SIZE + w).load()) for w in range(CMD_SIZE)])
 
-  bumped = put.after(copy.end(e)).index(0).store(put.index(0).load() + cnt)
-  if WIN: return sysbuf.after(bumped).index(0).store(put.after(bumped).index(0).load())
-
-  e = UOp.range(cnt, next(UOp.unique_num), dtype=dtypes.int, src=(bumped,))
-  return make_signal(devs, tag="func:sem_post").after(e).index(0).load().call(sem.after(e).index(0), ret_dtype=dtypes.void).end(e)
+  # wake the worker after each entry, keeping the post with the stores stops it from hoisting out of the loop
+  wake = copy.end(e) if WIN else make_signal(devs, tag="func:sem_post").after(copy).index(0).load().call(sem.index(0), ret_dtype=dtypes.void).end(e)
+  bumped = put.after(wake).index(0).store(put.index(0).load() + cnt)
+  return sysbuf.after(bumped).index(0).store(put.index(0).load() + cnt) if WIN else bumped
 
 # *****************
 
@@ -197,13 +196,11 @@ class CPUDevice(HCQ2Compiled):
   pm_lower = PatternMatcher([(UPat(Ops.CUSTOM_FUNCTION, arg="submit_cmdbuf", src=(UPat(Ops.LINEAR, name="q"),)), encode_queue)])
 
   def __init__(self, device:str=""):
-    self.workers:list[CPUWorker] = []
     super().__init__(device, CPUAllocator(self), [ClangRenderer, CPULLVMRenderer, LVPRenderer, X86Renderer], CPUProgram,
       arch={'amd64':'x86_64', 'aarch64':'arm64'}.get(m:=platform.machine().lower(), m)+",native")
 
     self.pm_bufferize = PatternMatcher(
-      [(UPat(Ops.PARAM, tag=f"{q}_{n}"), lambda ctx, q=q,n=n: getattr(ctx[0].worker(q), n))
-       for q in ("COMPUTE:0", "SUBMIT:0") for n in ("ring", "put", "sem", "sys", "done")] +
+      [(UPat(Ops.PARAM, tag=f"COMPUTE:0_{n}"), lambda ctx, n=n: getattr(ctx[0].worker, n)) for n in ("ring", "put", "sem", "sys", "done")] +
       [(UPat(Ops.PARAM, tag=f"func:{f}"), lambda ctx, f=f: ctx[0].func_ptr(f)) for f in FUNCS]) + self.pm_bufferize
 
     with Context(EMULATED_DTYPES="", TRACK_MATCH_STATS=0):
@@ -213,12 +210,6 @@ class CPUDevice(HCQ2Compiled):
 
   def func_ptr(self, name:str) -> Buffer: return self.func_table.view(1, dtypes.uint64, FUNCS.index(name)*8).ensure_allocated()
 
-  def synchronize(self, timeout:int|None=None):
-    for worker in self.workers:
-      put, done = (getattr(worker, x)._buf.cpu_view().view(fmt='Q') for x in ("put", "done"))
-      while done[0] < put[0]: self._wait_signal(done, put[0], timeout)
-    super().synchronize(timeout)
-
   @functools.cached_property
   def func_table(self) -> Buffer:
     lib = ctypes.windll.kernel32 if sys.platform == "win32" else libc.dll # type: ignore[attr-defined]
@@ -226,8 +217,8 @@ class CPUDevice(HCQ2Compiled):
       array.array('Q', [unwrap(ctypes.cast(getattr(lib, f), ctypes.c_void_p).value) for f in FUNCS])
     return ft
 
-  @functools.cache
-  def worker(self, queue:str) -> CPUWorker:
+  @functools.cached_property
+  def worker(self) -> CPUWorker:
     ring, put, sysbuf, done = (Buffer(self.device, sz, dtypes.uint64, preallocate=True) for sz in (RING_SLOTS*CMD_SIZE, 1, 1, 1))
     addr, hsem = 0, None
 
@@ -239,6 +230,5 @@ class CPUDevice(HCQ2Compiled):
     sem = Buffer(self.device, 1, dtypes.uint64, options=BufferSpec(external_ptr=addr), preallocate=True)
 
     worker_args = [ring._buf.va_addr, sysbuf._buf.va_addr if WIN else self.func_ptr('sem_wait')._buf.va_addr, done._buf.va_addr, addr]
-    (thread:=threading.Thread(target=self.prgs[worker_prog].fxn, daemon=True, args=[ctypes.c_uint64(x) for x in worker_args])).start()
-    self.workers.append(worker:=CPUWorker(ring, put, sem, sysbuf, done, thread))
-    return worker
+    (worker:=threading.Thread(target=self.prgs[worker_prog].fxn, daemon=True, args=[ctypes.c_uint64(x) for x in worker_args])).start()
+    return CPUWorker(ring, put, sem, sysbuf, done, worker)

tinygrad/runtime/ops_nv.py

@@ -588,7 +588,8 @@ class NVDevice(HCQCompiled[NVSignal]):
   def is_nvd(self) -> bool: return isinstance(self.iface, PCIIface)
 
   def __init__(self, device:str=""):
-    self.iface = self._select_iface(device)
+    self.device_id = int(device.split(":")[1]) if ":" in device else 0
+    self.iface = self._select_iface()
 
     device_params = nv_gpu.NV0080_ALLOC_PARAMETERS(deviceId=self.iface.gpu_instance, hClientShare=self.iface.root,
                                                    vaMode=nv_gpu.NV_DEVICE_ALLOCATION_VAMODE_OPTIONAL_MULTIPLE_VASPACES)

tinygrad/runtime/ops_rdma.py

@@ -101,5 +101,6 @@ class RDMAAllocator(HCQAllocatorBase):
 
 class RDMADevice(HCQCompiled):
   def __init__(self, device:str=""):
-    self.iface = MLXIface(self, int(device.split(":")[1]) if ":" in device else 0)
+    self.device_id = int(device.split(":")[1]) if ":" in device else 0
+    self.iface = MLXIface(self, self.device_id)
     super().__init__(device, RDMAAllocator(self), [], None, signal_t=None)

tinygrad/runtime/support/hcq.py

@@ -1,9 +1,10 @@
 from __future__ import annotations
 from typing import cast, Callable, Type, TypeVar, Generic, Any
-import contextlib, decimal, statistics, time, ctypes, array, os, struct, collections, itertools
+import contextlib, decimal, statistics, time, ctypes, array, os, struct, collections, functools, itertools
+from dataclasses import replace
 try: import fcntl # windows misses that
 except ImportError: fcntl = None #type:ignore[assignment]
-from tinygrad.helpers import DEV, PROFILE, getenv, to_mv, from_mv, cpu_profile, ProfileRangeEvent, unwrap
+from tinygrad.helpers import DEV, PROFILE, getenv, to_mv, from_mv, cpu_profile, ProfileRangeEvent, select_first_inited, select_by_name, unwrap
 from tinygrad.helpers import suppress_finalizing, pluralize, TracingKey
 from tinygrad.device import Device, BufferSpec, Compiled, LRUAllocator, ProfileDeviceEvent, ProfileProgramEvent, Program, TinyELF
 from tinygrad.uop.ops import sym_infer, sint, UOp
@@ -392,6 +393,8 @@ class HCQCompiled(Compiled, Generic[SignalType]):
   def __init__(self, device:str, allocator:HCQAllocatorBase, compilers:list[type[Renderer]], runtime:type[Program]|None,
                signal_t:Type[SignalType]|None=None, comp_queue_t:Callable[..., HWQueue]|None=None, copy_queue_t:Callable[..., HWQueue]|None=None,
                kernargs_size=(16 << 20), sigalloc_size=0x1000, can_recover:bool=False, arch=None):
+    self.device_id:int = int(device.split(":")[1]) if ":" in device else 0
+
     from tinygrad.runtime.graph.hcq import HCQGraph
     super().__init__(device, allocator, compilers, runtime, HCQGraph, arch=arch)
 
@@ -421,6 +424,8 @@ class HCQCompiled(Compiled, Generic[SignalType]):
 
     if self._is_cpu(): HCQCompiled.cpu_devices.append(self)
 
+  def count(self) -> int: return self.iface.count if hasattr(self, 'iface') else 1
+
   def synchronize(self, timeout:int|None=None):
     if self.error_state is not None: raise self.error_state
     if not hasattr(self, 'timeline_signal'): return
@@ -486,6 +491,16 @@ class HCQCompiled(Compiled, Generic[SignalType]):
       buf, realloced = self.allocator.alloc(oldbuf.size if oldbuf is not None else new_size, options=options), False
     return buf, realloced
 
+  def _select_iface(self):
+    assert (v:=getenv(k:=f'{type(self).__name__[:-6].upper()}_IFACE', "")) == "",  \
+      f"{k}={v} is deprecated, use DEV={replace(DEV.target(type(self).__name__[:-6]), interface=v)} instead"
+    assert hasattr(self, "ifaces"), "must have ifaces to select an iface"
+    t = DEV.target(dev:=type(self).__name__[:-6])
+    filtered = select_by_name(self.ifaces, lambda i: i.__name__[:-5], t.interface, f"{dev} has no interface {t.interface!r}")
+    filtered = [i for i in filtered if t.interface.startswith("MOCK") or not i.__name__[:-5].startswith("MOCK")] # never fallback to mock ifaces
+    return select_first_inited([functools.partial(cast(Callable, iface), self, self.device_id) for iface in filtered],
+                               f"No interface for {dev}:{self.device_id} is available")
+
   def _is_cpu(self) -> bool: return hasattr(self, 'device') and self.device.split(":")[0] == "CPU"
 
   def rdma_dev(self):
@@ -497,7 +512,9 @@ class HCQCompiled(Compiled, Generic[SignalType]):
   def finalize(self):
     try: self.synchronize() # Try to finalize device in any case.
     except RuntimeError as e: print(f"{self.device} synchronization failed before finalizing: {e}")
-    super().finalize()
+
+    # If the device has an interface, call its device_fini method to clean up resources.
+    if hasattr(self, 'iface') and hasattr(self.iface, 'device_fini'): self.iface.device_fini()
 
 class HCQBuffer:
   def __init__(self, va_addr:sint, size:int, meta:Any=None, _base:HCQBuffer|None=None, view:MMIOInterface|None=None, owner:Any=None):

tinygrad/runtime/support/hcq2.py

@@ -1,8 +1,8 @@
 from __future__ import annotations
-from typing import cast, TypeVar, Generic, Any, Sequence, Iterable
+from typing import cast, Callable, TypeVar, Generic, Any, Sequence, Iterable
 import struct, functools, time, collections, itertools, decimal, statistics
 from dataclasses import replace, dataclass
-from tinygrad.helpers import suppress_finalizing, dedup, pluralize, JIT_BATCH_SIZE, unwrap, PROFILE
+from tinygrad.helpers import DEV, getenv, select_first_inited, select_by_name, suppress_finalizing, dedup, pluralize, JIT_BATCH_SIZE, unwrap, PROFILE
 from tinygrad.helpers import to_tuple, round_up, partition, data64_le, panic, ContextVar, perf_counter_us, Context
 from tinygrad.device import Device, Buffer, BufferSpec, Compiled, LRUAllocator, MultiBuffer, DepsTracker
 from tinygrad.device import ProfileDeviceEvent, ProfileGraphEntry, ProfileGraphEvent
@@ -23,16 +23,17 @@ HCQDeviceType = TypeVar('HCQDeviceType', bound='HCQ2Compiled')
 HCQ_RUNTIME_DEV = ContextVar("HCQ_RUNTIME_DEV", "CPU")
 
 HCQ_DEVS = frozenset(("AMD", "CPU"))
-HCQ_CACHE_TAGS = frozenset(("program", "systems"))
+HCQ_P2P_DEVS = HCQ_DEVS | frozenset(("CPU",))
+HCQ_CACHE_TAGS = frozenset(("program", "systems", "template"))
 
 @dataclass(frozen=True)
 class HCQInfo:
   device:tuple[str, ...]
   estimates:Estimates = Estimates()
 
-  input_idxs:tuple[tuple[tuple[str, ...], tuple[int, ...]], ...] = () # per inputs table: (devices, indexes into input_uops)
-  inputs:int|None = None # index of the inputs table in call.src
-  kernels:tuple[tuple[tuple[str, ...], UOp, tuple[int, ...]], ...] = () # per kernel: (devices, a call carrying its name and estimates, timestamps)
+  input_idxs:tuple[int, ...] = () # indexes into input_uops used by this call
+  inputs:int|None = None
+  kernels:tuple[tuple[tuple[str, ...], str, Estimates, tuple[int, ...]], ...] = ()
 
 def all_devices_in(d:Any, c:frozenset[str]) -> bool: return {x.split(":")[0] for x in to_tuple(d)} <= c
 
@@ -93,10 +94,10 @@ pm_replace_buffers = PatternMatcher([(UPat(Ops.CALL, name="call"), replace_call_
 # *****************
 # 1.1. prep: staging copies
 
-def _need_staging(a, b): return all_devices_in(a.device, HCQ_DEVS - {"CPU"}) and not all_devices_in(b.device, HCQ_DEVS)
+def _need_staging(a, b): return all_devices_in(a.device, HCQ_DEVS - {"CPU"}) and not all_devices_in(b.device, HCQ_P2P_DEVS)
 
 def _get_enqueue_devs(call:UOp) -> Any|None:
-  if not (bufs:=call.src[1:]) or not all(all_devices_in(b.device, HCQ_DEVS) for b in bufs): return None
+  if not (bufs:=call.src[1:]) or not all(all_devices_in(b.device, HCQ_P2P_DEVS) for b in bufs): return None
   devs = min(bufs, key=lambda b: to_tuple(b.device)[0].startswith("CPU")).device # prio to enqueue on not CPU device
   return devs if all_devices_in(devs, HCQ_DEVS) else None
 
@@ -215,7 +216,7 @@ def _finalize_batch(batch:list[tuple[UOp, tuple[str, ...]]], profile:bool) -> li
     # and make hcq call
     name, info = get_call_name(call, get_call_arg_uops(call)), HCQInfo(devices, estimate_uop(call))
     ts_ids = [next(UOp.unique_num) for _ in range(2)] if profile else []
-    kerns.append((devices, make_call(name, call.src[0], info), tuple(ts_ids)))
+    kerns.append((devices, name, info.estimates, tuple(ts_ids)))
 
     ts_ins = [UOp(Ops.INS, arg="timestamp", src=(make_signal(devices, s),)) for s in ts_ids]
     q += ts_ins[:1] + [call.replace(arg=replace(call.arg, aux=info))] + ts_ins[1:]
@@ -345,11 +346,14 @@ def split_patches(call:UOp) -> UOp|None:
   scatter = make_scatter_loops(input_patches, tables[0], lt_patches)
   body = body.substitute({p:p.substitute(scatter | reads) for p in rt_patches})
 
+  if inputs: # fence inputs
+    fills.append((t:=tables[0][0]).after(make_binary_patch(t, bytes(t.max_numel() * 8)))) # zeroed at link, slot 0 is the host fence
+    body = body.replace(src=(UOp.sink(*body.src[0].src, t.after(*body.src[0].src).index(0).store(0)),)) # open it once consumed
+
   lt_srcs = collections.defaultdict(list)
   for p in lt_patches: lt_srcs[p.buf_uop].append(p)
   return call.replace(src=(body, *call.src[1:], *[b.after(*ps) for b,ps in lt_srcs.items()], *fills),
-    arg=replace(call.arg, aux=replace(call.arg.aux, input_idxs=((call.arg.aux.device,
-      tuple(sorted(dedup(b.arg.slot for g in inputs for b in unwrap_mstack(g.buf_uop))))),) if inputs else call.arg.aux.input_idxs)))
+    arg=replace(call.arg, aux=replace(call.arg.aux, input_idxs=tuple(sorted(dedup(b.arg.slot for g in inputs for b in unwrap_mstack(g.buf_uop)))))))
 pm_split_patches = PatternMatcher([(UPat(Ops.CALL, src=(UPat(Ops.CUSTOM_FUNCTION, arg="hcq"),), name="call", allow_any_len=True), split_patches)])
 
 # *****************
@@ -368,13 +372,14 @@ def replace_params(call:UOp) -> UOp|None:
 
   # keep buffers whose addresses become link-time constants alive and mapped
   held = args + [r.without_after for r in refhold]
-  addrs = dedup([g.src[0].without_after for g in call.toposort() if g.op is Ops.GETADDR])
+  addrs = dedup([g.src[0].without_after for x in call.src for g in x.toposort() if g.op is Ops.GETADDR])
   refhold += [a for a in addrs if a not in held and all(b.op is not Ops.PARAM or b.tag is not None for b in unwrap_mstack(a))]
 
   sub = {(b:=u.without_after): UOp.param(i, u.dtype, shape=b.shape, device=HCQ_RUNTIME_DEV.value, volatile=b.op is Ops.PARAM and b.arg.volatile)
          for i,u in enumerate(c_args)} | {v: v.replace(arg=replace(v.arg, slot=-1)) for v in variables if v.op is Ops.PARAM} | _rank_ranges(tops)
-  info = replace(call.arg.aux, inputs=next((i for i,u in enumerate(c_args + refhold) if u.without_after.tag == "inputs"), None))
-  return call.replace(src=(body.substitute(sub).replace(arg="hcq_args"), *c_args, *refhold), arg=replace(call.arg, aux=info))
+  info = replace(call.arg.aux, inputs=next((i for i,u in enumerate(c_args) if u.without_after.tag == "inputs"), None))
+  return call.replace(src=(body.substitute(sub).replace(arg="hcq_args"), *c_args, *refhold),
+                      arg=replace(call.arg, aux=info)) # TODO: call.after(*refhold)?
 pm_replace_params = PatternMatcher([
   (UPat(Ops.CALL, src=(UPat(Ops.CUSTOM_FUNCTION, arg="hcq"),), name="call", allow_any_len=True), replace_params)])
 
@@ -420,44 +425,8 @@ def callify_hcq(call:UOp, cf:UOp) -> UOp:
 pm_callify_hcq = PatternMatcher([(UPat(Ops.CALL, src=(
   UPat(Ops.CUSTOM_FUNCTION, arg="hcq_args", src=(UPat(Ops.SINK),), name="cf"),), name="call", allow_any_len=True), callify_hcq)])
 
-# *****************
-# 9. merge submitters
-
-def _lane_arg(a:UOp, lane:int, table:UOp) -> UOp: return table if a.tag == "inputs" else a.mselect(lane) if len(to_tuple(a.device)) > 1 else a
-
-def merge_batch(batch:list[UOp]) -> UOp:
-  tables = UOp.variable("hcq_inputs_ptr", 0, 2**64-1, dtypes.uint64, param=True)
-  lanes = [(c, j, sum(len(idxs) * 8 for _, idxs in c.arg.aux.input_idxs)) for c in batch for j in range(len(c.arg.aux.device))] # (call, lane, bytes)
-  offs = itertools.accumulate((table_bytes for _, _, table_bytes in lanes), initial=0) # every lane owns the next table of the region
-  cmds = [c.src[0].src[0].call(*[_lane_arg(a.without_after, j, tables + off) for a in c.src[1:]], UOp.variable("_device_num", 0, 1 << 30).bind(j))
-          for (c, j, _), off in zip(lanes, offs)]
-
-  info = HCQInfo((HCQ_RUNTIME_DEV.value,), sum((c.arg.aux.estimates for c in batch), start=Estimates()),
-                 input_idxs=tuple(x for c in batch for x in c.arg.aux.input_idxs), kernels=tuple(k for c in batch for k in c.arg.aux.kernels))
-  body = UOp.custom_function("hcq", make_submit(*cmds, devs=HCQ_RUNTIME_DEV.value, queue="SUBMIT:0").sink())
-  return body.call(*[s for c in batch for s in c.src[1:] if s.without_after.tag != "inputs"], name=f"hcq_submitter ({len(batch)})", aux=info)
-
-def merge_submitters(linear:UOp) -> UOp:
-  batches = [(k, list(g)) for k, g in itertools.groupby(linear.src, key=lambda c: isinstance(c.arg.aux, HCQInfo))]
-  return linear.replace(src=tuple(c for is_hcq, b in batches for c in ([merge_batch(b)] if is_hcq else b)))
-
-# *****************
-# hcq schedule
-
 hcq_compile_cache:dict[tuple[bytes, bool], UOp] = {}
 
-def hcq_lower(linear:UOp, pm_encode:PatternMatcher) -> UOp:
-  # lowering to hcq ir
-  linear = graph_rewrite(linear, pm_encode, walk=True, name="encode and pack", enter_calls=True)
-
-  # patches and runtime uops
-  linear = graph_rewrite(linear, pm_early_simplify+symbolic, bottom_up=False, name="simplify patches", enter_calls=True)
-  linear = graph_rewrite(linear, pm_split_patches, walk=True, name="split patches")
-
-  # and compile it
-  linear = graph_rewrite(linear, pm_replace_params, name="replace params")
-  return graph_rewrite(linear, pm_callify_hcq, name="callify hcq", enter_calls=True)
-
 @rewrite_group(lambda linear,input_uops,profile,ret: f"HCQ Compile {pluralize('Kernel', len(ret.src))}")
 def hcq_compile(linear:UOp, input_uops:list[UOp]|None, profile:bool) -> UOp:
   if input_uops is not None:
@@ -472,9 +441,16 @@ def hcq_compile(linear:UOp, input_uops:list[UOp]|None, profile:bool) -> UOp:
     # schedule
     linear = graph_rewrite(linear, pm_schedule_and_merge, ctx=({s:p for p,s in back_map.items()}, profile), walk=True, name="schedule and merge hcq")
 
-    # lower to hcq programs, then pack the programs of every batch into one C submitter (needs a C runtime device for the program addresses)
-    linear = hcq_lower(linear, pm_encode_cmdbufs+pm_pack_placeholders)
-    final_linear = hcq_compile_cache[cache_key] = hcq_lower(merge_submitters(linear), pm_encode_cmdbufs) if HCQ_RUNTIME_DEV.value == "CPU" else linear
+    # lowering to hcq ir
+    linear = graph_rewrite(linear, pm_encode_cmdbufs+pm_pack_placeholders, walk=True, name="encode and pack", enter_calls=True)
+
+    # patches and runtime uops
+    linear = graph_rewrite(linear, pm_early_simplify+symbolic, bottom_up=False, name="simplify patches", enter_calls=True)
+    linear = graph_rewrite(linear, pm_split_patches, walk=True, name="split patches")
+
+    # and compile it
+    linear = graph_rewrite(linear, pm_replace_params, name="replace params")
+    final_linear = hcq_compile_cache[cache_key] = graph_rewrite(linear, pm_callify_hcq, name="callify hcq", enter_calls=True)
 
   return final_linear
 
@@ -491,7 +467,7 @@ pm_bufferize = PatternMatcher([(UPat(Ops.PARAM, name="buf"), bufferize_buf)])
 # 7. resolve patches
 
 def push_stack(op, s): return UOp(Ops.STACK,
-  src=tuple(op.replace(dtype=op.dtype, src=tuple(x if y is s else y for y in op.src)) for x in s.src))
+  src=tuple(op.replace(dtype=op.dtype.scalar(), src=tuple(x if y is s else y for y in op.src)) for x in s.src))
 
 def fold_binary(buf:UOp, blob:UOp) -> UOp:
   for b in (m.bufs if isinstance(m:=buf.buffer, MultiBuffer) else (m,)):
@@ -556,6 +532,7 @@ class HCQ2Compiled(Compiled):
   wait_timeout_ms: float = 30000.0
 
   def __init__(self, device:str, allocator:HCQAllocator, compilers:list[type[Renderer]], runtime, can_recover:bool=False, arch=None):
+    self.device_id:int = int(device.split(":")[1]) if ":" in device else 0
     self.can_recover = can_recover
 
     self.pm_bufferize = PatternMatcher([
@@ -568,6 +545,7 @@ class HCQ2Compiled(Compiled):
 
     super().__init__(device, allocator, compilers, runtime, None, arch=arch)
 
+    self.rt_buffer = Buffer(self.device, 64 << 20, dtypes.uint8, options=BufferSpec(uncached=True, cpu_access=True))
     self.rt_allocator = BumpAllocator(64 << 20)
     self.prof_ents:dict[int, ProfileGraphEntry] = {}
 
@@ -591,10 +569,6 @@ class HCQ2Compiled(Compiled):
       tdiffs.append((st+perf_counter_us())/2 - gpu)
     Compiled.profile_events.append(ProfileDeviceEvent(self.device, statistics.median(tdiffs), self.device_props()))
 
-  @functools.cached_property
-  def rt_buffer(self) -> Buffer:
-    return Buffer(self.device, self.rt_allocator.size, dtypes.uint8, options=BufferSpec(uncached=True, cpu_access=True), preallocate=True)
-
   def new_buffer(self, b:UOp, cache:bool) -> Buffer:
     if cache or b.tag in HCQ_CACHE_TAGS:
       return Buffer(self.device, b.max_numel(), b.dtype, options=BufferSpec(uncached=True, cpu_access=True, nolru=True))
@@ -606,31 +580,42 @@ class HCQ2Compiled(Compiled):
     buf.as_memoryview(force_zero_copy=True, no_sync=True).cast('Q')[0] = init_value
     return buf
 
-  def _wait_signal(self, sig:memoryview, value:int, timeout:int|None=None):
-    timeout = timeout if timeout is not None and self.can_recover else None
-    st, done = time.perf_counter(), sig[0]
-    while done < value:
-      if done != (done:=sig[0]): st = time.perf_counter()
-      elif time.perf_counter() - st > (timeout or self.wait_timeout_ms) / 1000: self.on_device_hang()
-
   def synchronize(self, timeout:int|None=None):
     if HCQ_RUNTIME_DEV.value != self.device: Device[HCQ_RUNTIME_DEV.value].synchronize()
 
     sig = self.signal("timeline").as_memoryview(force_zero_copy=True, no_sync=True).cast('Q')
     tl = self.signal("value", 1).as_memoryview(force_zero_copy=True, no_sync=True).cast('Q')
-    self._wait_signal(sig, tl[0] - 1, timeout)
+    timeout = timeout if timeout is not None and self.can_recover else None
+    st, done = time.perf_counter(), sig[0]
+    while done < tl[0] - 1:
+      if done != (done:=sig[0]): st = time.perf_counter()
+      elif time.perf_counter() - st > (timeout or self.wait_timeout_ms) / 1000: self.on_device_hang()
     if self.prof_ents: self.collect_prof()
 
   def on_device_hang(self): raise RuntimeError(f"{self.device} hang detected")
 
   def device_props(self) -> dict[str,Any]: return {} # to be overridden if needed. dict keys are backend dependent.
 
+  def count(self) -> int: return self.iface.count if hasattr(self, 'iface') else 1
+
+  def _select_iface(self):
+    assert (v:=getenv(k:=f'{type(self).__name__[:-6].upper()}_IFACE', "")) == "",  \
+      f"{k}={v} is deprecated, use DEV={replace(DEV.target(type(self).__name__[:-6]), interface=v)} instead"
+    assert hasattr(self, "ifaces"), "must have ifaces to select an iface"
+    t = DEV.target(dev:=type(self).__name__[:-6])
+    filtered = select_by_name(self.ifaces, lambda i: i.__name__[:-5], t.interface, f"{dev} has no interface {t.interface!r}")
+    filtered = [i for i in filtered if t.interface.startswith("MOCK") or not i.__name__[:-5].startswith("MOCK")] # never fall back to mock ifaces
+    return select_first_inited([functools.partial(cast(Callable, iface), self, self.device_id) for iface in filtered],
+                               f"No interface for {dev}:{self.device_id} is available")
+
   def _is_cpu(self) -> bool: return hasattr(self, 'device') and self.device.split(":")[0] == "CPU"
 
   def finalize(self):
     try: self.synchronize() # try to finalize the device in any case
     except RuntimeError as e: print(f"{self.device} synchronization failed before finalizing: {e}")
-    super().finalize()
+
+    # if the device has an interface, call device_fini to clean up resources
+    if hasattr(self, 'iface') and hasattr(self.iface, 'device_fini'): self.iface.device_fini()
 
 @dataclass
 class HCQ2Buffer:

tinygrad/schedule/multi.py

@@ -22,14 +22,14 @@ def mstack_early_shrink(ms:UOp, shrink:UOp):
 
 def lower_broadcast_copy(c:UOp, x:UOp):
   if not (isinstance(c.device, tuple) and isinstance(x.device, str)): return None
-  if (sx:=x.simplify()).device is None: return UOp(Ops.MSTACK, src=(sx,)*len(c.device))
+  if (sx:=x.simplify()).device is None and sx.base.op is Ops.CONST: return UOp(Ops.MSTACK, src=(sx,)*len(c.device))
   return UOp(Ops.MSTACK, src=tuple(x.copy_to_device(d) for d in c.device))
 
 replace_allreduce = PatternMatcher([
   # BROADCAST: explicitly expand broadcast copies and combine with MSTACK
-  (UPat(Ops.COPY, name="c", src=(UPat(name="x"),)), lower_broadcast_copy),
+  (UPat(Ops.COPY, name="c", src=(UPat(GroupOp.All-{Ops.CONST}, name="x"),)), lower_broadcast_copy),
   # COPY_TO_ONE: if copying from multidevice to one, MSELECT the first (TODO: a little from each?)
-  (UPat(Ops.COPY, name="c", src=(UPat(name="x"),)), lambda c,x:
+  (UPat(Ops.COPY, name="c", src=(UPat(GroupOp.All-{Ops.CONST}, name="x"),)), lambda c,x:
     x.mselect(0).copy_to_device(c.device) if isinstance(c.device, str) and isinstance(x.device, tuple) else None),
   # MSELECT on MSTACK is replaced with nothing
   (UPat(Ops.MSELECT, src=(UPat(Ops.MSTACK, name="mstack"),), name="ms"), lambda mstack, ms: mstack.src[ms.arg]),

tinygrad/schedule/rangeify.py

@@ -313,9 +313,9 @@ pm_const_buffer_folding = pm_mops+PatternMatcher([
    lambda idx,after: idx.const_like(Invalid) if after_all_invalid(after) else None),
   # hack if a noop turned to a const
   (UPat(Ops.NOOP, src=(UPat.cvar("c"),)), lambda c: c),
-  # a deviceless MSTACK src is the same value on every device, so indexing the stack is just indexing that value
-  (UPat(Ops.MSTACK, src=(UPat.var("s"),), allow_any_len=True).f(Ops.INDEX, allow_any_len=True, name="idx"),
-   lambda s,idx: idx.replace(src=(s,)+idx.src[1:]) if s.device is None else None),
+  # mstack on CONST is CONST
+  (UPat(Ops.MSTACK, src=(UPat.var("s"),), allow_any_len=True).f(Ops.INDEX, allow_any_len=True),
+   lambda s: c if (c:=s.base).op is Ops.CONST else None),
 ])
 
 pm_remove_bufferize = PatternMatcher([

tinygrad/tensor.py

@@ -665,13 +665,13 @@ class Tensor(RandMixin):
     ```
     """
     all_uops = self.uop.toposort()
-    # backward fills .grad for every in-scope float tensor with a device
+    # backward fills .grad for every in-scope non-CONST float tensor
     tensors_need_grad: list[Tensor] = [t for tref in all_tensors if (t:=tref()) is not None and \
-                                       t.uop in all_uops and t.is_floating_point() and t.device is not None]
+                                       t.uop in all_uops and t.is_floating_point() and t.uop.op is not Ops.CONST]
     # clear contexts
     for t,g in zip(tensors_need_grad, self.gradient(*tensors_need_grad, gradient=gradient)):
       assert g.shape == t.shape, f"grad shape must match tensor shape, {g.shape!r} != {t.shape!r}"
-      if g.device is None: g = g.clone(device=t.device)
+      if g.device is None and t.device is not None: g = g.clone(device=t.device)
       if t.grad is None: t.grad = g
       else: t.grad.assign(t.grad + g.to(t.grad.device))
     return self

tinygrad/uop/ops.py

@@ -242,10 +242,9 @@ class UOp(RandMixin, metaclass=UOpMetaClass):
   arg:Any = None
   tag:Any = None
   def __del__(self):
-    # NOTE: getattr because this object may be partially constructed (e.g. if __init__ raised, like the BEAM timeout SIGALRM)
-    if Ops is not None and getattr(self, 'op', None) is Ops.BUFFER and (buffer:=buffers.get(self)) is not None: buffer.ref(-1)
+    if Ops is not None and self.op is Ops.BUFFER and (buffer:=buffers.get(self)) is not None: buffer.ref(-1)
     try: del UOpMetaClass.ucache[(self.op, self.dtype, self.src, self.arg, self.tag)]
-    except (AttributeError, KeyError): pass
+    except AttributeError: pass
   def __reduce__(self):
     args = [self.op, self.dtype, self.src, self.arg, self.tag, self.metadata]
     if self.op is Ops.BUFFER and self.realized is not None: args.append(self.realized)
@@ -471,6 +470,10 @@ class UOp(RandMixin, metaclass=UOpMetaClass):
     if (ret:=self._shape) is None: raise RuntimeError(f"shape requested, but {self.op} doesn't have a shape")
     return ret
 
+  @property
+  def max_shape(self) -> tuple[int, ...]: return to_max_shape(self.shape)
+  def max_numel(self) -> int: return prod(self.max_shape)
+
   @property
   def shard_shape(self) -> tuple[sint, ...]:
     if not isinstance(self.device, tuple) or self.axis is None: return self.shape
@@ -584,9 +587,9 @@ class UOp(RandMixin, metaclass=UOpMetaClass):
   def const_like(self, b:ConstLike, dtype:DType|None=None):
     ret = UOp.const(b, dtype or self.dtype)
     return ret._mop(Ops.EXPAND, arg=self._shape) if self._shape and ret._shape != self._shape else ret
-  def vconst_like(self, b:ConstLike):
+  def vconst_like(self, b:ConstLike, dtype:DType|None=None):
     # for use after movement ops have been removed
-    return UOp.const(b, self.dtype).broadcast(self.max_numel())
+    return UOp.const(b, dtype or self.dtype).broadcast(self.max_numel())
   def ufix(self, x):
     if isinstance(x, UOp): return x
     return UOp.const(x)
@@ -966,7 +969,7 @@ class UOp(RandMixin, metaclass=UOpMetaClass):
   # *** uop Variable stuff ***
 
   @staticmethod
-  def variable(name:str, min_val:PyConst, max_val:PyConst, dtype:DType=dtypes.weakint, multiple_of:int=1, param:bool=False) -> UOp:
+  def variable(name:str, min_val:PyConst, max_val:PyConst, dtype:DType=dtypes.int, multiple_of:int=1, param:bool=False) -> UOp:
     # a Variable is a 0-d BUFFER in the ALU addrspace; binding it is storing a CONST into it
     # param=True creates the kernel-side form directly: an ALU PARAM (what the BUFFER becomes inside kernels)
     arg = ParamArg(-1, dtype, name=name, vmin_vmax=(min_val, max_val), multiple_of=multiple_of, addrspace=AddrSpace.ALU)
@@ -1404,7 +1407,7 @@ class UPat(OpMixin):
     if self.is_any: return flatten([x.match(uop, store.copy()) for x in self.src[0]])
     if (self.op is not None and uop.op not in self.op) or \
        (self.name is not None and store.setdefault(self.name, uop) is not uop) or \
-       (self.match_dtype is not None and uop.dtype not in self.match_dtype) or \
+       (self.match_dtype is not None and uop.dtype not in self.match_dtype and uop.dtype.scalar() not in self.match_dtype) or \
        (self.arg is not None and self.arg != uop.arg) or \
        (self.match_tag is not None and uop.tag not in self.match_tag) or \
        (len(uop.src) < self.required_len) or \