When investigating failures in https://github.com/pytorch/pytorch/pull/100017 I realized that we were reentering FakeTensorMode even though there was already one on the stack. Although we have attempted assert for these cases in the past, e.g., as in https://github.com/pytorch/pytorch/pull/97186 it seems that the existing protections were insufficient.
In this particular case, the reapplication of FakeTensorMode was due to an interaction with NotImplemented multiple dispatch handling. If proxy tensor mode detects an unrecognized tensor type (this includes FakeTensor, if it is not tracked with a proxy), it will return NotImplemented to give this tensor a chance to unpack itself into proxyable operation. However, this is never the right thing for FakeTensor, where no unpacking is possible. However, today, FakeTensor attempts to reapply the FakeTensorMode, resulting in FakeTensorMode being twice on the stack.
This PR does a number of things:
* It adds an assert in `FakeTensorMode.__torch_dispatch__` that you must not already have this mode on the stack, this is ALWAYS an error
* It modifies `FakeTensor.__torch_dispatch__` to return `NotImplemented` if the mode is already active. This prevents us from readding the mode on the stack
* It adds a new logging artifact `not_implemented` which you can use to get debug logs about all of the times a `__torch_dispatch__` handler returned NotImplemented and why it did so. Your subclass has to manually opt into this logging, but I inserted the necessary logs for ProxyTensorMode and FakeTensor(Mode)
* `with fake_mode` now no-ops if the fake mode is already on the stack, which is what users want anyway
* I am BREAKING pre-autograd tracing, because it is currently doing something weird with the original C++ mode stack. Brian is going to follow up with a fix next week.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/102091
Approved by: https://github.com/thiagocrepaldi, https://github.com/eellison, https://github.com/wanchaol, https://github.com/bdhirsh
The bug was that: if you want to move a mode to the autograd key, we need to use the "functionality" key for it (AutogradFunctionality). But when we do that, we need to clear any PythonDispatcher caches for every op for **every** autograd key (since you could run autograd ops with both cpu and cuda tensors underneath the mode, which both may have been cached).
I didn't add a test, since this ends up getting indirectly tests by export in the PR. If someone would prefer a direct test I can add one.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/98030
Approved by: https://github.com/ezyang
This PR improves the list/tuple handling by merging the logic into
`wrap_with_proxy` directly, and set_meta when we find the current
proxy is a fx.Proxy. This also solves the problem that even `fused_adam`
have `val`, some corresponding `getitem` calls followed after `fused_adam` don't have val
Pull Request resolved: https://github.com/pytorch/pytorch/pull/99897
Approved by: https://github.com/ezyang
This PR introduces CustomOp, a wrapper around a dispatcher operator that allows
users to define custom operators. It adds the skeleton for CustomOp and
some very simple behavior: as of this PR:
- one can create a CustomOp for an operator that does not have inplace or aliasing
- give it CPU/CUDA and Meta implementations
- and trace it into a graph via make_fx.
The design follows
https://docs.google.com/document/d/19Uc5OUCA187q9BZggJb70RT2ZoSTDoG5QQkJkZwd25M/edit
Concretely, we implement the following things mentioned in the doc in this PR:
- Entrypoint 1 (CustomOp.define, creating a new custom operator)
- impl (to define device-specific code) and impl_meta (to define meta
formulas)
The goal for the short term is to get the code to a state where it can be trialed
by the export folks. On top of this PR, the blockers are:
- adding Entrypoint 3 (CustomOp.from_existing)
- adding a way to do data-dependent shape formulas
These will come in future PRs since this one is getting long.
Things that will come in the longer-near-term (before 2.1):
- adding the other entrypoints mentioned in the doc (2 & 3)
- more safety checks and better error messages
- support for views and mutation
- support for defining autograd formulas
- support for functionalization
- making this API public (it's private right now).
Test Plan:
- added a new test case, TestCustomOp. It mostly tests a bunch of error
cases.
- added OpInfos for custom operators and hooked these up to
test_proxy_tensor to test that they work with make_fx. These custom
operators were based off of the ones in the autograd_function_db.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/98440
Approved by: https://github.com/ezyang
The purpose of this API is to execute a few large components of work:
1) Refactor all the internals of plumbing dynamic dimension information after dynamo to be stateless
2) Decouple allocation controls around dynamic dimensions from verification
3) For (2), for allocation, create an enum that dictates whether we are in DUCK (default today), STATIC (aka assume_static_default in the past), or DYNAMIC (aka user constrained, do not duck shape)
4) For (2), for verification, we separate out the list of dynamic ranges entirely from allocation. This means shape_env does not tracking for what we verify on, and instead, it is the callers job to invoke produce_guards() with the various things they want verified, specifically, with the valid ranges. We do use constrain ranges to refine value ranges when doing analysis.
5) We have decided, therefore, as an extension of (4) to double down on "late" checks versus "eager" checks, primarily because the mechanisms for gathering what actually matters happens during guards, and should be a purview of the caller seeking guards, not the shape env. However, for dynamo, these structures are essentially one and the same.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/96699
Approved by: https://github.com/avikchaudhuri, https://github.com/ezyang
This removes the need to explicitly constrain_unify `x[mask]` and `y[mask]` when mask is a boolean tensor. It's very narrow but it seems to work in practice.
To invalidate the nonzero call when mutation occurs, I use version counter. I know there are ways to bypass this but I think it's good enough for now.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/95399
Approved by: https://github.com/eellison
This takes the strategy described in https://docs.google.com/document/d/1lFRYAJo5nrfxRhwIzGnfi2pbLpU6T4ytSRSuLJ5qebI/edit#
It is essentially https://github.com/pytorch/pytorch/pull/95222 but squashed and with changes that are unnecessary given that we assume nonzero returns > 1.
What's in the PR:
* nonzero now supports meta propagation. When `capture_dynamic_output_shape_ops`, it will return a tensor with an unbacked SymInt representing the size in question.
* The unbacked SymInt is UNSOUNDLY assumed to be not equal to 0/1. We will still error if you guard otherwise.
* PrimTorch pointwise operators are updated to use empty_permuted, to avoid guarding on unbacked SymInt from empty_strided (tested in `test_dynamic_pointwise_scalar`)
* Convolution is updated to skip backend selection if batch is unbacked, to avoid guarding on unbacked SymInt (tested in `test_unbacked_batch_resnet`)
* I kept the helper utilities like `definitely_true` for working with possibly unbacked SymInts. They're not used right now but maybe someone will find them useful.
* Added `constrain_unify` to let you specify two unbacked SymInts must have the same value
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/95387
Approved by: https://github.com/voznesenskym
torch.empty_permuted is a generalized version of torch.empty(memory_format=...), where you can pass an arbitrary physical layout as a tuple of dims to allow you to setup dense, non-overlapping tensors with non-standard memory format. Check the docblock for a full description of semantics.
The initial motivation for this PR is with guard-less unbacked SymInts. Traditionally, the way we allocate dense tensors with arbitrary layout is with `empty_strided`. However, `empty_strided` does not know that the given strides are actually contiguous, and must test this manually to find out if it is the case. With `empty_permuted`, this is known statically to be the case and helps us skip some 0/1 guards.
However, I also think torch.empty_permuted is a useful API in its own right. It is technically possible to simulate this with an empty and a permute; however, there are some downsides:
* The manual incant is tricky to work out. To allocate an NHWC tensor, the invocation is `torch.empty(N, H, W, C).permute(0, 3, 1, 2)`; the permute call has to take NHWC to NCHW, and is the *inverse* of the permutation people are typically thinking of when they talk about NHWC (0, 2, 3, 1). Instead, torch.empty_permuted lets you say `torch.empty_permuted((N, C, H, W), (0, 2, 3, 1))`, letting you provide the intuitive permutation. It can be literally be read off as NHWC if you assign N=0, C=1, H=2, W=3.
* An empty(requires_grad=True).permute() is no longer a leaf tensor. You can force it to be a leaf with a detach(), but it is more straightforward and less error prone to allow directly allocating a tensor with the correct permutation.
It is also technically possible to simulate this with empty_strided. However, this requires the user to manually compute the contiguous output strides and is bad from a reduction of guards perspective. For what it's worth, this is one of the more common uses of as_strided in the wild, and it would be nice to get rid of it.
A nice enhancement of this feature would be to accept `physical_layout` anywhere `memory_format` is accepted. However, this would be a pretty involved change, so I'm doing the easy thing instead.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/95069
Approved by: https://github.com/malfet, https://github.com/ngimel, https://github.com/albanD, https://github.com/dagitses
This PR introduces a new `constrain_range` function which can be used to constrain the possible values a SymInt/SymFloat can take on. This knowledge can be then used to discharge potential guards (by running the range analysis, and then seeing if the guard must be true given the original range) without adding another guard.
The usage of ranges is very limited right now; ranges are only constrained when the user explicitly instructs the system so. However, we can also infer range constraints based on guards as well; this is left for future work.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/95063
Approved by: https://github.com/eellison
With this change, expected failures will be correctly reported as such by pytest (instead of passes as before).
It was sometimes a little confusing to see operators you did not expect to work in inductor reported as passing their tests.
One downside is that expected failures/skips for test variants have now to be identified by tuples. I.e., `("max", "reduction_no_dim"): {f16},` instead of just `"max.reduction_no_dim": {f16}`. It seems to me it is worth it.
This change would also allow to simplify `TestInductorOpInfo` class a little, since it doesn't have to handle the skips/xfails anymore, but that might require dropping support for things like `PYTORCH_COLLECT_EXPECT` and `PYTORCH_FAIL_ON_SUCCESS` so I didn't do it.
Also couple of other minor changes:
- Got rid of c32, c64, c128 in torchinductor_opinfo. We don't support complex numbers, so they shouldn't be necessary.
- Renamed TestExpect Enum to ExpectedTestResult to get rid of a pytest warning that thinks it is a class that has tests.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94813
Approved by: https://github.com/lezcano, https://github.com/jansel
This PR removes the unnecessary == 0 guard when constructing empty tensors, by ensuring that when we create a contiguous tensor we go directly to the C++ torch.empty implementation (instead of indirecting through empty_strided), where we can bypass doing zero tests when computing the size of the storage. This probably also speeds up trace time.
When I did this, I found out that `empty_tensor_restride_symint` was flagrantly wrong (we had never exercised it before because we redirected to `empty_strided` in PrimTorch decomp, which doesn't hit this codepath.) The bugs:
* Stride computation was wrong (only `last_idx` was ever written to)
* Using set_sizes_and_strides with `sym_sizes` input doesn't work, because there is some sort of ordering problem where `clone_symvec` isn't safe when you clone a vector into itself. Probably should fix this.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94512
Approved by: https://github.com/ngimel
This is the main payload of this diff stack. With it, we are able to construct a 1D tensor from unbacked SymInt with guards that are equivalent to asserting that the size is non-negative (which makes sense!) To get here, I had to arrange for all of the guards that occur when doing contiguity tests to be lazy. This was done by writing non-branching implementations of each of the tests in `sympy_is_contiguous` etc functions, and then using those implementations when we don't branch.
I also had to do some bug fixes for `is_non_overlapping_and_dense`, as unbacked SymInts were very untested previously (and that was the only time you would actually hit the Python version of the code.) In particular, we now consistently pass separate sizes/strides lists into each of the boolean computation functions (and only pack them into a single argument list when going to Sympy, which doesn't support lists of variables in custom functions.)
Finally, to actually test that this is doing something, I add a simple assumptions system from https://github.com/pytorch/pytorch/pull/90985 and use this to get the end to end test test_item_to_constructor passing. Soon, I intend to replace this with a range analysis system which will be used for assumptions in the short term. (We still might use Z3, but for all the stray assumptions I've seen range analysis will be good enough.)
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94473
Approved by: https://github.com/albanD
With this change, expected failures will be correctly reported as such by pytest (instead of passes as before).
It was sometimes a little confusing to see operators you did not expect to work in inductor reported as passing their tests.
One downside is that expected failures/skips for test variants have now to be identified by tuples. I.e., `("max", "reduction_no_dim"): {f16},` instead of just `"max.reduction_no_dim": {f16}`. It seems to me it is worth it.
This change would also allow to simplify `TestInductorOpInfo` class a little, since it doesn't have to handle the skips/xfails anymore, but that might require dropping support for things like `PYTORCH_COLLECT_EXPECT` and `PYTORCH_FAIL_ON_SUCCESS` so I didn't do it.
Also couple of other minor changes:
- Got rid of c32, c64, c128 in torchinductor_opinfo. We don't support complex numbers, so they shouldn't be necessary.
- Renamed TestExpect Enum to ExpectedTestResult to get rid of a pytest warning that thinks it is a class that has tests.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94813
Approved by: https://github.com/lezcano, https://github.com/jansel
Changes:
* Add `simplified` kwarg to let you only render guards that are nontrivial (excludes duck sizing)
* Make a list of strings valid for sources, if you just have some variable names you want to bind to
* Add test helper `show_guards` using these facilities, switch a few tests to it
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94404
Approved by: https://github.com/Chillee
I applied some flake8 fixes and enabled checking for them in the linter. I also enabled some checks for my previous comprehensions PR.
This is a follow up to #94323 where I enable the flake8 checkers for the fixes I made and fix a few more of them.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94601
Approved by: https://github.com/ezyang
### Motivation of this PR
This patch is to migrate `spmm_reduce` from `torch-sparse` (a 3rd party dependency for PyG) to `torch`, which is a response to the initial proposal for fusion of **Gather, Apply Scatter** in Message Passing of GNN inference/training. https://github.com/pytorch/pytorch/issues/71300
**GAS** is the major step for Message Passing, the behavior of **GAS** can be classified into 2 kinds depending on the storage type of `EdgeIndex` which records the connections of nodes:
* COO: the hotspot is `scatter_reduce`
* CSR: the hotspot is `spmm_reduce`
The reduce type can be choose from: "max", "mean", "max", "min".
extend `torch.sparse.mm` with an `reduce` argument, maps to `torch.sparse_mm.reduce` internally.
`sparse_mm_reduce` is registered under the TensorTypeId of `SparseCsrCPU`, and this operator requires an internal interface `_sparse_mm_reduce_impl` which has dual outputs:
* `out` - the actual output
* `arg_out` - records output indices in the non zero elements if the reduce type is "max" or "min", this is only useful for training. So for inference, it will not be calculated.
### Performance
Benchmark on GCN for obgn-products on Xeon single socket, the workload is improved by `4.3x` with this patch.
Performance benefit for training will be bigger, the original backward impl for `sum|mean` is sequential; the original backward impl for `max|min` is not fused.
#### before:
```
----------------------------- ------------ ------------ ------------ ------------ ------------ ------------
Name Self CPU % Self CPU CPU total % CPU total CPU time avg # of Calls
----------------------------- ------------ ------------ ------------ ------------ ------------ ------------
torch_sparse::spmm_sum 97.09% 56.086s 97.09% 56.088s 6.232s 9
aten::linear 0.00% 85.000us 1.38% 795.485ms 88.387ms 9
aten::matmul 0.00% 57.000us 1.38% 795.260ms 88.362ms 9
aten::mm 1.38% 795.201ms 1.38% 795.203ms 88.356ms 9
aten::relu 0.00% 50.000us 0.76% 440.434ms 73.406ms 6
aten::clamp_min 0.76% 440.384ms 0.76% 440.384ms 73.397ms 6
aten::add_ 0.57% 327.801ms 0.57% 327.801ms 36.422ms 9
aten::log_softmax 0.00% 23.000us 0.10% 55.503ms 18.501ms 3
```
#### after
```
----------------------------- ------------ ------------ ------------ ------------ ------------ ------------
Name Self CPU % Self CPU CPU total % CPU total CPU time avg # of Calls
----------------------------- ------------ ------------ ------------ ------------ ------------ ------------
aten::spmm_sum 87.35% 11.826s 87.36% 11.827s 1.314s 9
aten::linear 0.00% 92.000us 5.87% 794.451ms 88.272ms 9
aten::matmul 0.00% 62.000us 5.87% 794.208ms 88.245ms 9
aten::mm 5.87% 794.143ms 5.87% 794.146ms 88.238ms 9
aten::relu 0.00% 53.000us 3.35% 452.977ms 75.496ms 6
aten::clamp_min 3.35% 452.924ms 3.35% 452.924ms 75.487ms 6
aten::add_ 2.58% 348.663ms 2.58% 348.663ms 38.740ms 9
aten::argmax 0.42% 57.473ms 0.42% 57.475ms 14.369ms 4
aten::log_softmax 0.00% 22.000us 0.39% 52.605ms 17.535ms 3
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/83727
Approved by: https://github.com/jgong5, https://github.com/cpuhrsch, https://github.com/rusty1s, https://github.com/pearu
By moving guard string assembly into dynamo's default behavior and letting code_parts do the work, we can have much better shape guard failures.
Before this fix, the guard failure in the test would look like:
```
'x.size()[1] == x.size()[0] and x.stride()[0] == x.[264 chars]!= 1' != 'x.size()[0] < 3'
- x.size()[1] == x.size()[0] and x.stride()[0] == x.size()[0] and x.stride()[1] == 1 and x.storage_offset() == 0 and y.size()[0] == x.size()[0] and y.size()[1] == x.size()[0] and y.stride()[0] == x.size()[0] and y.stride()[1] == 1 and y.storage_offset() == 0 and x.size()[0] < 3 and x.size()[0] != 0 and x.size()[0] != 1
+ x.size()[0] < 3
```
now it is
```
"x.size()[0] < 3"
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/93894
Approved by: https://github.com/ezyang
We'll rely on the underlying fake tensor to raise an error in these cases. We only raise the error if there is an input to the data dependent operation that is a real tensor (and thus we are at risk of accidentally burning in real values)
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/93265
Approved by: https://github.com/albanD
This PR:
- Updates the docs to say it is deprecated
- Raises a UserWarning
- Changes most of the callsites inside PyTorch to use
torch.func.functional_call, minus the test_stateless testing.
The motivation behind this is that we can now align behind a single
functional_call API in PyTorch.
Test Plan:
- existing tests
Pull Request resolved: https://github.com/pytorch/pytorch/pull/92280
Approved by: https://github.com/albanD
Whenever you guard on something, you're supposed to tell GuardBuilder about it, so GuardBuilder knows that it has to actually bind it in scope when it creates the guard function. But shape env guards bypass that mechanism completely. Well, now they don't.
For the most part, this didn't matter in practice, because we usually had a `TENSOR_MATCH` guard floating around that made sure that the guard stayed live. But if we ever eliminate those guards (e.g., because we build it into the shape guard directly; something we'll probably want to do when https://github.com/pytorch/pytorch/pull/89707 goes online) then this will indeed matter.
One complication: some of the shape env guards are on globals. You have to make sure to shunt the usage to the correct guard builder in that case. Maybe it would be better if we refactored things so there is only one GuardBuilder. Not sure.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/91058
Approved by: https://github.com/voznesenskym
I'm going to need this in the follow up PR. Instead of storing only Source.name() in Symbol, I now store a full on Source. Lots of replumbing reoccurs. In particular:
- Move Source to torch._guards to break cycles
- I have to add TensorPropertySource and NegateSource to handle x.size()[0] and -x codegen that I was doing with string manipulation previously
- I tighten up invariants so that I never pass source=None; instead I pass ConstantSource (these are constant sources right) and test for that rather than source being missing. I think this is more parsimonious
- Some mypy wobbles from new imports
I didn't move LocalSource and friends to torch._guards, but I ended up needing to access them in a few places. The main annoyance with moving these is that then I also need to move the bytecode codegen stuff, and that's not so easy to move without bringing in the kitchen sink.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/91057
Approved by: https://github.com/albanD, https://github.com/voznesenskym, https://github.com/zou3519
This PR moves the definitions for:
* `sym_int`
* `sym_ceil` (used only for `sym_int`)
* `sym_floor` (used only for `sym_int`)
* `sym_float`
from `torch/fx/experimental/symbolic_shapes.py` to `torch/__init__.py`, where `SymInt` and `SymFloat` are already defined.
This removes the need for several in-line imports, and enables proper JIT script gating for #91318. I'm very open to doing this in a better way!
Pull Request resolved: https://github.com/pytorch/pytorch/pull/91317
Approved by: https://github.com/ezyang, https://github.com/anijain2305
I'm going to need this in the follow up PR. Instead of storing only Source.name() in Symbol, I now store a full on Source. Lots of replumbing reoccurs. In particular:
- Move Source to torch._guards to break cycles
- I have to add TensorPropertySource and NegateSource to handle x.size()[0] and -x codegen that I was doing with string manipulation previously
- I tighten up invariants so that I never pass source=None; instead I pass ConstantSource (these are constant sources right) and test for that rather than source being missing. I think this is more parsimonious
- Some mypy wobbles from new imports
I didn't move LocalSource and friends to torch._guards, but I ended up needing to access them in a few places. The main annoyance with moving these is that then I also need to move the bytecode codegen stuff, and that's not so easy to move without bringing in the kitchen sink.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/91057
Approved by: https://github.com/albanD, https://github.com/voznesenskym
Previously, we planned to lift the parameters and weights while exporting and implement our own transformer to "unlift" the lifted weights and params back to the graph as attributes. But this is bit challenging because:
- We need to maintain correct ordering for weights and parameters that are passed as inputs so that we know how to map them back.
- Some weights are unused in the graph, so our transformer needs to be aware of which weights and parameters are not used in the graph. And we need to distinguish which are real user input and which are parameters.
- There can be more edge cases we haven't seen in other models yet.
I am aware that @Chillee and @bdhirsh mentioned that functionalization won't work with fake-tensor attributes but this is fine for the short term as we don't expect users to be modifying weights and params in inference mode. In fact, we explicitly disable attribute mutation in torchdynamo export mode right now.
Given above condition, it might be ok to just fakify params when we need. I use a flag to guard against this change.
Differential Revision: [D41891201](https://our.internmc.facebook.com/intern/diff/D41891201)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90417
Approved by: https://github.com/eellison
The big idea is to add `create_unbacked_symfloat` and `create_unbacked_symint` to ShapeEnv, allowing you to allocate symbolic floats/ints corresponding to data you don't know about at compile time. Then, instead of immediately erroring out when you try to call local_scalar_dense on a FakeTensor, we instead create a fresh symint/symfloat and return that.
There a bunch of odds and ends that need to be handled:
* A number of `numel` calls converted to `sym_numel`
* When we finally return from item(), we need to ensure we actually produce a SymInt/SymFloat when appropriate. The previous binding code assumed that you would have to get a normal Python item. I add a pybind11 binding for Scalar (to PyObject only) and refactor the code to use that. There is some trickiness where you are NOT allowed to go through c10::SymInt if there isn't actually any SymInt involved. See comment.
* One of our unit tests tripped an implicit data dependent access which occurs when you pass a Tensor as an argument to a sizes parameter. This is also converted to support symbolic shapes
* We now support tracking bare SymInt/SymFloat returns in proxy tensor mode (this was already in symbolic-shapes branch)
* Whenever we allocate an unbacked symint, we record the stack trace it was allocated at. These get printed when you attempt data dependent access on the symint (e.g., you try to guard on it)
* Subtlety: unbacked symints are not necessarily > 1. I added a test for this.
These unbacked symints are not very useful right now as you will almost always immediately raise an error later when you try to guard on them. The next logical step is adding an assertion refinement system that lets ShapeEnv learn facts about unbacked symints so it can do a better job eliding guards that are unnecessary.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90624
Approved by: https://github.com/Skylion007, https://github.com/voznesenskym
Instead of inferring shape mappings from a bunch of data structures that were plumbed in InstructionTranslator, we instead work out mappings by just iterating over the GraphArgs and mapping symbols to arguments as they show up. If multiple argument sizes/strides/offset map to the same symbol, this means they are duck sized, so we also generate extra equality tests that they must be equal. Finally, we generate 0/1 specialization guards. The resulting code is much shorter, and I think also easier to understand.
TODO: Delete all the tensor ref tracking code, it's unnecessary
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90528
Approved by: https://github.com/voznesenskym
So, uh, I have a new strategy for generating dupe guards, one where I don't actually need to allocate symints for every tensor that is fakeified. So I'm reverting the changes I made from earlier PRs in this one.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90381
Approved by: https://github.com/voznesenskym
We may need to express guards on the size/stride/storage offset of
a tensor, but we cannot do this if it's already been duck sized.
This PR guarantees that we allocate a symbol (or negation of the
symbol) whenever we ask to create a SymInt, and propagates this
symbol to SymNode so that Dynamo can look at it (not in this PR).
This PR doesn't actually add guards, nor does Dynamo do anything
with these symbols.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/89879
Approved by: https://github.com/albanD
The idea is to add a custom handler to Functionalize key in Python
dispatcher that runs the functionalized version along side a non
functionalized version, and checks that their outputs agree in the
end. (Technically, for metadata mutation we should also check the
inputs, but for now we're relying on those functions returning self.)
I turned this on for test_functionalize.py (new TestCrossRefFunctionalize)
and found a bunch of failures that look legit.
This probably doesn't interact that nicely if you're also tracing at
the same time, probably need more special logic for that (directly,
just disabling tracing for when we create the nested fake tensor mode,
but IDK if there's a more principled way to organize this.)
There are some misc fixups which I can split if people really want.
- xfail_inherited_tests moved to test common_utils
- Bindings for _dispatch_tls_set_dispatch_key_included,
_dispatch_tls_is_dispatch_key_included and _functionalization_reapply_views_tls
- Type stubs for _enable_functionalization, _disable_functionalization
- all_known_overloads utility to let you iterate over all OpOverloads
in all namespaces. Iterator support on all torch._ops objects to let
you iterate over their members.
- suspend_functionalization lets you temporarily disable functionalization mode
in a context
- check_metadata_matches for easily comparing outputs of functions and see
if they match (TODO: there are a few copies of this logic, consolidate!)
- _fmt for easily printing the metadata of a tensor without its data
- _uncache_dispatch for removing a particular dispatch key from the cache,
so that we force it to regenerate
- check_significant_strides new kwarg only_cuda to let you also do stride
test even when inputs are not CUDA
- Functionalize in torch._C.DispatchKey
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/89498
Approved by: https://github.com/malfet
We add most in-place references in a generic way. We also implement a
wrapper to implement the annoying interface that `nn.functional`
nonlinearities have.
We fix along the way a couple decompositions for some non-linearities by
extending the arguments that the references have.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/88117
Approved by: https://github.com/mruberry
Fake tensor behaves pretty differently depending on if you have
symbolic shapes or not. This leads to bugs; for example, we
weren't getting correct convolution_backward strides because we
bypassed the correct stride logic in fake tensor on symbolic
shapes.
This PR attempts to unify the two codepaths. I don't manage to
unify everything, but I get most of it. The algorithm is delicate
and I'm still hosing down test failures.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/89038
Approved by: https://github.com/anjali411
This refactor was prompted by challenges handling mixed int/float
operations in C++. A previous version of this patch
added overloads for each permutation of int/float and was unwieldy
https://github.com/pytorch/pytorch/pull/87722/ This PR takes a different
approach.
The general outline of the patch is to combine the C++ types SymIntNode
and SymFloatNode into a single type, SymNode. This is type erased; we
no longer know statically at C++ if we have an int/float and have to test
it with the is_int()/is_float() virtual methods. This has a number of
knock on effects.
- We no longer have C++ classes to bind to Python. Instead, we take an
entirely new approach to our Python API, where we have a SymInt/SymFloat
class defined entirely in Python, which hold a SymNode (which corresponds
to the C++ SymNode). However, SymNode is not pybind11-bound; instead,
it lives as-is in Python, and is wrapped into C++ SymNode using PythonSymNode
when it goes into C++. This implies a userland rename.
In principle, it is also possible for the canonical implementation of SymNode
to be written in C++, and then bound to Python with pybind11 (we have
this code, although it is commented out.) However, I did not implement
this as we currently have no C++ implementations of SymNode.
Because we do return SymInt/SymFloat from C++ bindings, the C++ binding
code needs to know how to find these classes. Currently, this is done
just by manually importing torch and getting the attributes.
- Because SymInt/SymFloat are easy Python wrappers, __sym_dispatch__ now
takes SymInt/SymFloat, rather than SymNode, bringing it in line with how
__torch_dispatch__ works.
Some miscellaneous improvements:
- SymInt now has a constructor that takes SymNode. Note that this
constructor is ambiguous if you pass in a subclass of SymNode,
so an explicit downcast is necessary. This means toSymFloat/toSymInt
are no more. This is a mild optimization as it means rvalue reference
works automatically.
- We uniformly use the caster for c10::SymInt/SymFloat, rather than
going the long way via the SymIntNode/SymFloatNode.
- Removed some unnecessary toSymInt/toSymFloat calls in normalize_*
functions, pretty sure this doesn't do anything.
- guard_int is now a free function, since to guard on an int you cannot
assume the method exists. A function can handle both int and SymInt
inputs.
- We clean up the magic method definition code for SymInt/SymFloat/SymNode.
ONLY the user classes (SymInt/SymFloat) get magic methods; SymNode gets
plain methods; this is to help avoid confusion between the two types.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
cc @jansel @mlazos @soumith @voznesenskym @yanboliang @penguinwu @anijain2305
Pull Request resolved: https://github.com/pytorch/pytorch/pull/87817
Approved by: https://github.com/albanD, https://github.com/anjali411
**Introduces symbolic shape guards into dynamo.**
In this PR, we take the existing fake tensor infra and plumbing in dynamo and we start passing a shape_env around. This shape_env does not get plumbed down to middle layers / backend yet - it only collects expressions from frontend invocations at the moment. We then translate these expressions into guards at the point where we take other guards installed throughout dynamo - and add them to check_fn.
Part 1 of https://docs.google.com/document/d/1QJ-M4zfMkD-fjHIqW089RptjLl9EgozZGCceUbvmgfY/edit#
cc @jansel @lezcano @fdrocha @mlazos @soumith @yanboliang @penguinwu @anijain2305
Pull Request resolved: https://github.com/pytorch/pytorch/pull/87570
Approved by: https://github.com/ezyang
Big-bang PR to symintify **all** .sizes() calls in derivatives.yaml, which will be needed for symbolic tracing.
* with the exception of `split()`, which is tougher to land because it requires internal changes.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86610
Approved by: https://github.com/albanD
This reverts commit 978b46d7c9.
Reverted https://github.com/pytorch/pytorch/pull/86488 on behalf of https://github.com/osalpekar due to Broke executorch builds internally with the following message: RuntimeError: Missing out variant for functional op: aten::split.Tensor(Tensor(a -> *) self, SymInt split_size, int dim=0) -> Tensor(a)[] . Make sure you have loaded your custom_ops_generated_lib
symintify split_with_sizes, dropout, fused_fake_obs_quant. meta for padding_2d ops
add meta_bernoulli_
meta kernel for at::gather
get pytorch_struct to pass: meta for scatter_add, fix backward
symintify split ops
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86488
Approved by: https://github.com/ezyang
symintify split_with_sizes, dropout, fused_fake_obs_quant. meta for padding_2d ops
add meta_bernoulli_
meta kernel for at::gather
get pytorch_struct to pass: meta for scatter_add, fix backward
symintify split ops
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86334
Approved by: https://github.com/ezyang
It's not clear to me what's the difference between `unfold` and `unfold_copy`, as this latter one is codegen'd
I also took this chance to clean the implementation of unfold and its reference
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85629
Approved by: https://github.com/mruberry
- TensorGeometry supports symint
- check_size supports symint
- functorch batch rule improved symint
- Some operator support for symint in LTC
- More supported operations on SymInt and SymFloat
- More symint support in backwards formulas
This merge includes code contributions from bdhirsh and anjali411.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86160
Approved by: https://github.com/Chillee
Duck shaping says that when two input tensors have the same
size, we assume they are symbolically related. This follows
the same optimization done by inductor.
This optimization is not done completely because we don't
currently install guards corresponding to the duck shape
relationships we created, but overall the guard propagation
for dynamic shape tracing is incomplete at the moment.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85808
Approved by: https://github.com/albanD
This is based on wconstab tests from #84680
Technically, slice is covered by the __getitem__ opinfo, but it is
easier to debug/test on a more narrow internal function that only
uses this functionality and not other advanced indexing stuff.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85554
Approved by: https://github.com/mruberry, https://github.com/wconstab
This results in some test wobbling, which looks legit. I also
added some debug helpers for stuff that I found useful while
working on this.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85260
Approved by: https://github.com/albanD
- Support storing SymFloat in IValue
- Add SymFloat to JIT type system (erases to float)
- Printing support for SymFloat
- add/sub/mul/truediv operator support for SymFloat
- Support truediv on integers, it returns a SymFloat
- Support parsing SymFloat from Python object
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85411
Approved by: https://github.com/albanD
- previous impl compared the summed bool values of the tensor to its nelem, which in a symbolic world is a symint and can't be coerced back into a bool for the purpose of shoving into a result tensor
- new impl adds one extra negation op but avoids the need to compare to the symbolic nelem
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85352
Approved by: https://github.com/ezyang, https://github.com/mruberry
- Lazily allocate FX nodes for size/stride accessors on proxy tensor
- Properly track derived computations on strides/numel/etc
- Remove unnecessary tree_map at end of proxy tensor trace checking
invariants; we will just have to be smart (it's too expensive)
- Avoid tree_map in sym proxy tracing
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85049
Approved by: https://github.com/wconstab
Signed-off-by: Edward Z. Yang <ezyangfb.com>
From @ezyang's original PR:
There are a number of situations where we have non-backend kernels (e.g., CompositeImplicitAutograd, batching rules) which we would like to port to Python, but we have no way to integrate these ports with the overall system while using preexisting C++ registrations otherwise. This PR changes that by introducing a Python dispatcher (which can have its own kernels directly in Python), which can be interpose over ordinary C++ dispatch. The ingredients:
We introduce a new PythonDispatcher dispatch key, that has the same tenor as FuncTorchDynamicLayerFrontMode: it works by getting triggered before every other dispatch key in the dispatch key, and shunting to a Python implementation
The Python dispatcher is a per-interpreter global object that is enabled/disabled via the guard EnablePythonDispatcher/DisablePythonDispatcher. We don't make it compositional as I have no idea what a compositional version of this feature would look like. Because it is global, we don't need to memory manage it and so I use a simpler SafePyHandle (newly added) to control access to this pointer from non-Python C++. Like __torch_dispatch__, we use PyInterpreter to get to the Python interpreter to handle the dispatch.
I need to reimplement dispatch table computation logic in Python. To do this, I expose a lot more helper functions for doing computations on alias dispatch keys and similar. I also improve the pybind11 handling for DispatchKey so that you can either accept the pybind11 bound enum or a string; this simplifies our binding code. See https://github.com/pybind/pybind11/issues/483#issuecomment-1237418106 for how this works; the technique is generally useful.
I need to be able to call backend fallbacks. I do this by permitting you to call at a dispatch key which doesn't have a kernel for the operator; if the kernel doesn't exist, we check the backend fallback table instead.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/84826
Approved by: https://github.com/ezyang
