# Dynamo allow in graph fail on tensor.view(dtype)

**URL:** <https://dev-discuss.pytorch.org/t/dynamo-allow-in-graph-fail-on-tensor-view-dtype/1326>\
**Category:** compiler\
**Created:** [June 13, 2023, 10:03pm UTC](https://dev-discuss.pytorch.org/t/dynamo-allow-in-graph-fail-on-tensor-view-dtype/1326 "2023-06-13T22:03:52Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![thong3le](https://yyz2.discourse-cdn.com/flex036/user_avatar/dev-discuss.pytorch.org/thong3le/32/957_2.png) [@thong3le](https://dev-discuss.pytorch.org/u/thong3le)\
**Post date:** [June 13, 2023, 10:03pm UTC](https://dev-discuss.pytorch.org/t/dynamo-allow-in-graph-fail-on-tensor-view-dtype/1326/1 "2023-06-13T22:03:52Z")

</div>

hi team, I am trying to run dynamo on python function which contains `tensor.view(dtype)` operation,  
I know that this can’t be captured by dynamo, so I added `foo` into list of allow functions, e.g. `dynamo.allow_in_graph(foo)`.  
however, dynamo still fails to run. Is this a bug or expected behavior? would be great if someone could help to take a look.

cc @ezyang who might know the answer

```auto
import torch
import torch._dynamo as dynamo

def foo(a):
    b = a.view(torch.int8)
    return b

def bar(x):
    x = x + 1
    y = foo(x)
    z = y * 2
    return z

torch.manual_seed(42)
x = torch.randn(1,3)

dynamo.allow_in_graph(foo)
dynamo.explain(bar, x)

```

Full stack trace,

```auto
fake tensor raised TypeError
Traceback (most recent call last):
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_subclasses/fake_tensor.py", line 987, in __torch_dispatch__
    return self.dispatch(func, types, args, kwargs)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_subclasses/fake_tensor.py", line 1170, in dispatch
    r = func(*args, **kwargs)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_ops.py", line 287, in __call__
    return self._op(*args, **kwargs or {})
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_refs/ __init__.py", line 3988, in view
    return _reshape_view_helper(a, *shape, allow_copy=False)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_refs/ __init__.py", line 3152, in _reshape_view_helper
    shape = utils.infer_size(shape, a.numel())
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_prims_common/ __init__.py", line 725, in infer_size
    elif d >= 0:
TypeError: '>=' not supported between instances of 'torch.dtype' and 'int'
Traceback (most recent call last):
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_dynamo/utils.py", line 1194, in run_node
    return node.target(*args, **kwargs)
  File "/home/thonle/dev/dynamo/repro_fp16.py", line 5, in foo
    b = a.view(torch.int8)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/utils/_stats.py", line 20, in wrapper
    return fn(*args, **kwargs)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_subclasses/fake_tensor.py", line 987, in __torch_dispatch__
    return self.dispatch(func, types, args, kwargs)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_subclasses/fake_tensor.py", line 1170, in dispatch
    r = func(*args, **kwargs)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_ops.py", line 287, in __call__
    return self._op(*args, **kwargs or {})
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_refs/ __init__.py", line 3988, in view
    return _reshape_view_helper(a, *shape, allow_copy=False)
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_refs/ __init__.py", line 3152, in _reshape_view_helper
    shape = utils.infer_size(shape, a.numel())
  File "/home/thonle/.local/lib/python3.8/site-packages/torch/_prims_common/ __init__.py", line 725, in infer_size
    elif d >= 0:
TypeError: '>=' not supported between instances of 'torch.dtype' and 'int'

```

---

<div class="post-metadata">

**Author:** ![Lezcano](https://yyz2.discourse-cdn.com/flex036/user_avatar/dev-discuss.pytorch.org/lezcano/32/300_2.png) [@Lezcano](https://dev-discuss.pytorch.org/u/Lezcano)\
**Post date:** [June 17, 2023, 11:43am UTC](https://dev-discuss.pytorch.org/t/dynamo-allow-in-graph-fail-on-tensor-view-dtype/1326/2 "2023-06-17T11:43:16Z")

</div>

Are you using commit ahead of [[Inductor] Fix x.view(dtype) decomp and make inductor support it by yanboliang · Pull Request #102920 · pytorch/pytorch · GitHub](https://github.com/pytorch/pytorch/pull/102920)?