Differential Revision: D63206258
This diff introduces a mechanism to generate a json-compatible deserializer in cpp using nlohmann json (already being used by AOTI).
Why we need this? Because there will be a lot of cases where people don't want to use Python to load the graph (e.g. cpp runtime), and instead they can use this header to deserialize the JSON graph.
Every time we call update_schema.py to update the schema, the header will be auto generated and included into the source files.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/136398
Approved by: https://github.com/angelayi
Summary:
had a land racing with another diff D65166035 to fix the schema.
According to export team's discussion, we are upgrading min_val and max_val to optional fields which shouldn't break BC and allows the schema to express infinity.
Test Plan: buck2 test 'fbcode//mode/opt' fbcode//apf/rec/ir/tests:ir_export_deserialize_test
Differential Revision: D65273170
Pull Request resolved: https://github.com/pytorch/pytorch/pull/139394
Approved by: https://github.com/yiming0416
Summary:
This diff reverts D65167805
broke the release pipeline
Test Plan: NA
Differential Revision: D65245198
@diff-train-skip-merge (to silent facebook-github-bot until I have a stamp to land this)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/139371
Approved by: https://github.com/malfet
Summary: According to export team's discussion, we are upgrading min_val and max_val to optional fields which shouldn't break BC and allows the schema to express infinity.
Test Plan: buck test mode/opt caffe2/test:test_export -- -r test_serialize_infinite_sym_int
Differential Revision: D65167805
Pull Request resolved: https://github.com/pytorch/pytorch/pull/139223
Approved by: https://github.com/yiming0416
Summary:
Unflatten was broken for HOPs for a couple of reasons:
(1) we didn't expect `get_attr` nodes in the exported program, but they can occur to hold graph arguments to HOPs; such attributes must be moved from the exported program to the corresponding unflattened submodule containing the HOP call.
(2) we don't record metadata for graph arguments on serialization (there's nothing to hold it in our schema), and accordingly the `get_attr` nodes we create on deserialization don't have `nn_module_stack` metadata, which obviously wrecks unflatten.
Test Plan: added a couple of tests
Differential Revision: D65013647
Pull Request resolved: https://github.com/pytorch/pytorch/pull/138978
Approved by: https://github.com/zhxchen17
Currently when we deserialize inputs to nodes, we deserialize arguments with default values as kwargs. So deserializing `aten.uniform`, which has the signature `uniform(Tensor(a!) self, float from=0, float to=1, *, Generator? generator=None) -> Tensor(a!)`, will get become `uniform(x, from=0, to=1)`. However, this fails when running in python because `from` is a python keyword. So the solution here is to not deserialize it as a kwarg.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/136036
Approved by: https://github.com/zhxchen17
Summary: In general I think it will be useful to also record the global torch version in the EP, so that we can track them in the logging in addition to the schema version.
Test Plan: CI
Reviewed By: henryoier
Differential Revision: D62252626
Pull Request resolved: https://github.com/pytorch/pytorch/pull/135243
Approved by: https://github.com/yushangdi
`nn_module_stack` was previously serialized to string by adding commas between the module_path and module_type. This error prone when the `nn_module_stack` itself contains commas.
This PR fixes this by creating a dictionary to store the `nn_module_stack` and serialize it to string via `json.dumps()`
Fixes#131941
Pull Request resolved: https://github.com/pytorch/pytorch/pull/134049
Approved by: https://github.com/angelayi
Summary: Some element of tensor list output doesn't not have a user. In such case, create a name as `{node_name}_unused_{index}` for it.
Test Plan: OSS CI
Differential Revision: D61309011
Pull Request resolved: https://github.com/pytorch/pytorch/pull/133539
Approved by: https://github.com/zhxchen17
Summary:
Add a special field in Graph and Node level metadata called "custom" which should be mapped to a json-serializable object, and we guarantee this field should be always preversed across the following transformations:
1. copy/deepcopy
2. run_decompositions()
3. serialization
4. re-exporting
Test Plan: :test_export -- -r custom_tag
Reviewed By: angelayi
Differential Revision: D60291839
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131912
Approved by: https://github.com/angelayi
Summary:
- make default DCE pass check schema,
- need to rebase onto https://github.com/pytorch/pytorch/pull/131651 after it's in phabricator (for now the change is manually added).
- mark Proxy dump as NotImplemented for better error msg
- Remove Proxy from tensors when dumping models, as Proxy cannot be dumped.
More details in https://docs.google.com/document/d/1G5vmTXjzxoyVGRI2kpA1gQukK_Glyg2NrE0Oh6Nlg9A/edit?usp=sharing.
Test Plan:
CI
```
- buck2 run 'fbcode//mode/dev-nosan' fbcode//caffe2/test/quantization:test_quantization -- -r qat_conv2d
- test_export.py
- buck2 run 'fbcode//mode/dev-nosan' fbcode//modai/test:test_modai -- -r test_qat_stinson_htp_export
- buck2 run 'fbcode//mode/dev-nosan' fbcode//vizard_projects/ml_depth/tests:test_model -- -r test_qat_model_et
- buck2 run 'fbcode//mode/dev-nosan' fbcode//caffe2/test:fx -- -r dce
- buck2 run 'fbcode//mode/dev-nosan' fbcode//bolt/nn/executorch/backends/tests:qnn_test -- -r test_qat_bias=False,use_3d_input=False
- buck2 run 'fbcode//mode/dev-nosan' fbcode//bolt/nn/executorch/backends/tests:qnn_test -- -r test_qat_bias=True,use_3d_input=False
- buck2 run 'fbcode//mode/dev-nosan' fbcode//caffe2/test/quantization:test_quantization -- -r test_fold_bn_erases_bn_node
```
Reviewed By: angelayi
Differential Revision: D60319175
Pull Request resolved: https://github.com/pytorch/pytorch/pull/132764
Approved by: https://github.com/angelayi
Context:
We are planning to make a BC breaking change to `torch.load` by flipping the default for `weights_only` from `False` --> `True` in a future release. With `weights_only=True`, a custom unpickler is used that limits what can be loaded to state_dicts containing tensors (there is also a way for the user to allowlist specific things to be loaded). The goal of this is to attempt to prevent remote execution of arbitrary code when using `torch.load`.
To my understanding, in export, `torch.load` is used internally to load arbitrary objects, so we should set `weights_only=False` here to prevent the flip from breaking export.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/132348
Approved by: https://github.com/angelayi
Sets `prefer_deferred_runtime_asserts_over_guards=True` for export, so any guards emitted from `SymNode.expect_true` (for example, guards that are implicitly required to be true for an op to succeed) won't lead to constraint violations. Instead these should appear in the graph as runtime asserts, or potentially as replacement expressions for placeholder shapes.
For example, this reshape op should emit s0 * s1 = s2, deferred as a runtime assert.
```
x = torch.randn(4, 8) # [s0, s1]
y = torch.randn(32) # [s2]
out = x.reshape(-1) + y
# this emits Eq(s0 * s1, s2), and we represent y's shape as [s0*s1] in the graph.
```
However, other complex guards can still cause export to fail, for instance guards emitted from `SymNode.guard_bool/guard_size_oblivious` (e.g. explicit if-else conditions in user code or lower-level op implementations hit during tracing) can still raise constraint violations. These can be deferred with `allow_complex_guards_as_runtime_asserts=True`. We don't yet make this default, because while this makes export more likely to succeed, it results in non-trivial asserts being emitted that often represent specialization to a variant of the op, or checks related to 0/1 specialization.
We also remove forced specializations for export and kill the `_disable_forced_specializations` flag - now any guard we can't express with Dims/DerivedDims either are handled with Hybrid SymInts, or should be resolved with rewriting or deferring.
Follow up:
Currently, `ShapeEnv._set_replacement()` is called for complex equality expressions (e.g. s2 -> s0*s1 in the example above), and the ExportedProgram stores `s0*s1` in the input placeholder. This isn't checked for validity when the program is run, so an option is to avoid replacement and/or runtime assert on equality.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130775
Approved by: https://github.com/avikchaudhuri
Summary: Finishing up the mechanism to "register" certain types of operators to a registry so that the serializer can handle them correctly. This is expected to be firstly used by executorch.
Test Plan: buck run mode/opt caffe2/test:test_export -- -r test_export_with_extension_op_serialization
Differential Revision: D59825148
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130851
Approved by: https://github.com/angelayi
Summary: `quantization_tag` is a first class citizen metadata in quantization flows that is preserved by it. As we'll want to store the quantized exported graphs we also need to preserve this metadata as it's used in later flows. Only json supported metadata will be allowed to be serialized.
Test Plan: Added test case
Differential Revision: D57939282
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127473
Approved by: https://github.com/angelayi
Summary: This diff updates the ExportedProgram class in PyTorch to allow for multiple verifiers to be attached to it. This is done by adding a new field to the ExportedProgram schema called "verifiers" which is a list of strings representing the names of the verifiers to be attached to the program. The verifiers are loaded using the "load_verifier" function which is defined in the "torch._export.serde.serialize" module. The "exported_program.dialect" field is also deprecated in favor of the "verifiers" field.
Test Plan: CI
Differential Revision: D59408546
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130364
Approved by: https://github.com/angelayi, https://github.com/ydwu4
original PR: https://github.com/pytorch/pytorch/pull/128599 (re-created after revert + poisoned diff train)
Summary:
This PR adds deduplication and CSE for runtime asserts. Existing size computation in the graph is CSE'd along with added runtime asserts, and redundant asserts are removed. Shape calls on intermediate tensors are also turned into compute on input sizes if possible, allowing intermediate tensors to be freed earlier. For example:
```
z = torch.cat([x, x], dim=0) # 2*s0
w = z.repeat(y.shape[0]) # 2*s0*s1
_w = w.shape[0]
s0 = x.shape[0]
s1 = y.shape[0]
_w0 = 2 * s0
_w = _w0 * s1
```
Additionally, constrain_range calls are deduplicated. Single-symbol bound checks for unbacked symbols (e.g. u0 >= 0, u0 <= 5) and sym_constrain_range.default calls are also removed, since they accumulate range info in the ShapeEnv, and are replaced with two _assert_scalar.default calls that check the min/max bounds. For example:
```
torch.sym_constrain_range_for_size(n, min=2, max=16)
torch.sym_constrain_range(n, min=4, max=20)
torch._check(n >= 0)
torch._check(n >= 3)
torch._check(n <= 14)
torch.sym_constrain_range_for_size(n)
torch._check(n >= 4)
torch._check(n <= 14)
```
Test Plan:
contbuild & OSS CI, see 940e4477ab
Original Phabricator Test Plan:
Imported from GitHub, without a `Test Plan:` line.
Differential Revision: D59543603
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130380
Approved by: https://github.com/izaitsevfb
Fixes the example in #118304 for `torch._functorch.aot_autograd.aot_export_module` and `torch.export.export`.
On a high level, the issue is caused by not detecting fake_mode when there's no input.
Change plan:
1) we add a `dynamic_shapes: Union[bool, None] = None` arg to `aot_export_module` and `_aot_export_function`.
2) if the input is not a graph module, then we can only rely on this `dynamic_shapes` input arg.
3) If the input is a graph module, then we can traverse the graph and check.
4) So we check if the input mod is a graph module or just a module, and do 2) or 3) depending on the type.
Fixes#129927
Bug source: dynamo's fake_mode is not detected correctly in `_convert_input_to_fake` in `_traced.py` when there’s no input to the graph). So in ` _strict_export_lower_to_aten_ir`, we create another fake_mode. `dynamo_fake_mode` is not the same as the fake_mode used by dynamo.
Change plan:
check `gm_torch_level` graph's node meta "example_value" for fake mode in addition.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/129928
Approved by: https://github.com/angelayi
This PR adds deduplication and CSE for runtime asserts. Existing size computation in the graph is CSE'd along with added runtime asserts, and redundant asserts are removed. Shape calls on intermediate tensors are also turned into compute on input sizes if possible, allowing intermediate tensors to be freed earlier. For example:
```
z = torch.cat([x, x], dim=0) # 2*s0
w = z.repeat(y.shape[0]) # 2*s0*s1
_w = w.shape[0]
# something with _w ...
# turns into ->
s0 = x.shape[0]
s1 = y.shape[0]
_w0 = 2 * s0
_w = _w0 * s1
```
Additionally, constrain_range calls are deduplicated. Single-symbol bound checks for unbacked symbols (e.g. u0 >= 0, u0 <= 5) and sym_constrain_range.default calls are also removed, since they accumulate range info in the ShapeEnv, and are replaced with two _assert_scalar.default calls that check the min/max bounds. For example:
```
torch.sym_constrain_range_for_size(n, min=2, max=16)
torch.sym_constrain_range(n, min=4, max=20)
torch._check(n >= 0)
torch._check(n >= 3)
torch._check(n <= 14)
# turns into
torch.sym_constrain_range_for_size(n)
torch._check(n >= 4)
torch._check(n <= 14)
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/128599
Approved by: https://github.com/ezyang
This PR adds deduplication and CSE for runtime asserts. Existing size computation in the graph is CSE'd along with added runtime asserts, and redundant asserts are removed. Shape calls on intermediate tensors are also turned into compute on input sizes if possible, allowing intermediate tensors to be freed earlier. For example:
```
z = torch.cat([x, x], dim=0) # 2*s0
w = z.repeat(y.shape[0]) # 2*s0*s1
_w = w.shape[0]
# something with _w ...
# turns into ->
s0 = x.shape[0]
s1 = y.shape[0]
_w0 = 2 * s0
_w = _w0 * s1
```
Additionally, constrain_range calls are deduplicated. Single-symbol bound checks for unbacked symbols (e.g. u0 >= 0, u0 <= 5) and sym_constrain_range.default calls are also removed, since they accumulate range info in the ShapeEnv, and are replaced with two _assert_scalar.default calls that check the min/max bounds. For example:
```
torch.sym_constrain_range_for_size(n, min=2, max=16)
torch.sym_constrain_range(n, min=4, max=20)
torch._check(n >= 0)
torch._check(n >= 3)
torch._check(n <= 14)
# turns into
torch.sym_constrain_range_for_size(n)
torch._check(n >= 4)
torch._check(n <= 14)
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/128599
Approved by: https://github.com/ezyang
In a previous life, we used sympy.oo to represent the lower/upper bounds of integer ranges. Later, we changed this to be sys.maxsize - 1 for a few reasons: (1) sometimes we do tests on a value being exactly sys.maxsize, and we wanted to avoid a data dependent guard in this case, (2) sympy.oo corresponds to floating point infinity, so you get incorrect types for value ranges with oo, and (3) you can do slightly better reasoning if you assume that input sizes fall within representable 64-bit integer range.
After working in the sys.maxsize regime for a bit, I've concluded that this was actually a bad idea. Specifically, the problem is that you end up with sys.maxsize in your upper bound, and then whenever you do any sort of size-increasing computation like size * 2, you end up with 2 * sys.maxsize, and you end up doing a ton of arbitrary precision int computation that is totally unnecessary. A symbolic bound is better.
But especially after #126905, we can't go back to using sympy.oo, because that advertises that it's not an integer, and now your ValueRanges is typed incorrectly. So what do we do? We define a new numeric constant `int_oo`, which is like `sympy.oo` but it advertises `is_integer`. **test/test_sympy_utils.py** describes some basic properties of the number, and **torch/utils/_sympy/numbers.py** has the actual implementation.
The rest of the changes of the PR are working out the implications of this change. I'll give more commentary as inline comments.
Fixes https://github.com/pytorch/pytorch/issues/127396
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127693
Approved by: https://github.com/lezcano
ghstack dependencies: #126905
In a previous life, we used sympy.oo to represent the lower/upper bounds of integer ranges. Later, we changed this to be sys.maxsize - 1 for a few reasons: (1) sometimes we do tests on a value being exactly sys.maxsize, and we wanted to avoid a data dependent guard in this case, (2) sympy.oo corresponds to floating point infinity, so you get incorrect types for value ranges with oo, and (3) you can do slightly better reasoning if you assume that input sizes fall within representable 64-bit integer range.
After working in the sys.maxsize regime for a bit, I've concluded that this was actually a bad idea. Specifically, the problem is that you end up with sys.maxsize in your upper bound, and then whenever you do any sort of size-increasing computation like size * 2, you end up with 2 * sys.maxsize, and you end up doing a ton of arbitrary precision int computation that is totally unnecessary. A symbolic bound is better.
But especially after #126905, we can't go back to using sympy.oo, because that advertises that it's not an integer, and now your ValueRanges is typed incorrectly. So what do we do? We define a new numeric constant `int_oo`, which is like `sympy.oo` but it advertises `is_integer`. **test/test_sympy_utils.py** describes some basic properties of the number, and **torch/utils/_sympy/numbers.py** has the actual implementation.
The rest of the changes of the PR are working out the implications of this change. I'll give more commentary as inline comments.
Fixes https://github.com/pytorch/pytorch/issues/127396
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127693
Approved by: https://github.com/lezcano
ghstack dependencies: #126905
At a high level, the idea behind this PR is:
* Make it clearer what the promotion and int/float rules for various Sympy operations are. Operators that previously were polymorphic over int/float are now split into separate operators for clarity. We never do mixed int/float addition/multiplication etc in sympy, instead, we always promote to the appropriate operator. (However, equality is currently not done correctly.)
* Enforce strict typing on ValueRanges: if you have a ValueRange for a float, the lower and upper MUST be floats, and so forth for integers.
The story begins in **torch/utils/_sympy/functions.py**. Here, I make some changes to how we represent certain operations in sympy expressions:
* FloorDiv now only supports integer inputs; to do float floor division, do a truediv and then a trunc. Additionally, we remove the divide out addition by gcd optimization, because sympy gcd is over fields and is willing to generate rationals (but rationals are bad for ValueRange strict typing).
* ModularIndexing, LShift, RShift now assert they are given integer inputs.
* Mod only supports integer inputs; eventually we will support FloatMod (left for later work, when we build out Sympy support for floating operations). Unfortunately, I couldn't assert integer inputs here, because of a bad interaction with sympy's inequality solver that is used by the offline solver
* TrueDiv is split into FloatTrueDiv and IntTrueDiv. This allows for us to eventually generate accurate code for Python semantics IntTrueDiv, which is written in a special way to preserve precision when the inputs are >= 2**53 beyond what first coercing the integer to floats and then doing true division.
* Trunc is split to TruncToFloat and TruncToInt.
* Round is updated to return a float, not an int, making it consistent with the round op handler in Inductor. To get Python-style conversion to int, we call TruncToInt on the result.
* RoundDecimal updated to consistently only ever return a float
* Add ToFloat for explicit coercion to float (required so we can enforce strict ValueRanges typing)
In **torch/__init__.py**, we modify SymInt and SymFloat to appropriately call into new bindings that route to these refined sympy operations. Also, we modify `torch.sym_min` and `torch.sym_max` to have promotion semantics (if one argument is a float, the return result is always a float), making them inconsistent with builtins.min/max, but possible to do type analysis without runtime information.
We also need to introduce some new op handlers in **torch/_inductor/ops_handler.py**:
* `to_int` for truncation to int64, directly corresponding to TruncToInt; this can be implemented by trunc and dtype, but with a dedicated handler it is more convenient for roundtripping in Sympy
* `int_truediv` for Python-style integer true division, which has higher precision than casting to floats and then running `truediv`
These changes have consequences. First, we need to make some administrative changes:
* Actually wire up these Sympy functions from SymInt/SymFloat in **torch/fx/experimental/sym_node.py**, including the new promotion rules (promote2)
* Add support for new Sympy functions in **torch/utils/_sympy/interp.py**, **torch/utils/_sympy/reference.py**
* In particular, in torch.utils._sympy.reference, we have a strong preference to NOT do nontrivial compute, instead, everything in ops handler should map to a singular sympy function
* TODO: I chose to roundtrip mod back to our Mod function, but I think I'm going to have to deal with the C/Python inconsistency this to fix tests here
* Add printer support for the Sympy functions in **torch/_inductor/codegen/common.py**, **torch/_inductor/codegen/cpp_utils.py**, **torch/_inductor/codegen/triton.py**. `int_truediv` and mixed precision equality is currently not implemented soundly, so we will lose precision in codegen for large values. TODO: The additions here are not exhaustive yet
* Update ValueRanges logic to use new sympy functions in **torch/utils/_sympy/value_ranges.py**. In general, we prefer to use the new Sympy function rather than try to roll things by hand, which is what was done previously for many VR analysis functions.
In **torch/fx/experimental/symbolic_shapes.py** we need to make some symbolic reasoning adjustments:
* Avoid generation of rational subexpressions by removing simplification of `x // y` into `floor(x / y)`. This simplification then triggers an addition simplification rule `(x + y) / c --> x / c + y / c` which is bad because x / c is a rational number now
* `_assert_bound_is_rational` is no more, we no longer generate rational bounds
* Don't intersect non-int value ranges with the `int_range`
* Support more sympy Functions for guard SYMPY_INTERP
* Assert the type of value range is consistent with the variable type
The new asserts uncovered necessary bug fixes:
* **torch/_inductor/codegen/cpp.py**, **torch/_inductor/select_algorithm.py**, **torch/_inductor/sizevars.py** - Ensure Wild/Symbol manually allocated in Inductor is marked `is_integer` so it's accepted to build expressions
* **torch/_inductor/utils.py** - make sure you actually pass in sympy.Expr to these functions
* **torch/_inductor/ir.py** - make_contiguous_strides_for takes int/SymInt, not sympy.Expr!
* **torch/export/dynamic_shapes.py** - don't use infinity to represent int ranges, instead use sys.maxsize - 1
Because of the removal of some symbolic reasoning that produced rationals, some of our symbolic reasoning has gotten worse and we are unable to simplify some guards. Check the TODO at **test/test_proxy_tensor.py**
**Reland notes.** This requires this internal fbcode diff https://www.internalfb.com/phabricator/paste/view/P1403322587 but I cannot prepare the diff codev due to https://fb.workplace.com/groups/osssupport/posts/26343544518600814/
It also requires this Executorch PR https://github.com/pytorch/executorch/pull/3911 but the ET PR can be landed prior to this landing.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/126905
Approved by: https://github.com/xadupre, https://github.com/lezcano
At a high level, the idea behind this PR is:
* Make it clearer what the promotion and int/float rules for various Sympy operations are. Operators that previously were polymorphic over int/float are now split into separate operators for clarity. We never do mixed int/float addition/multiplication etc in sympy, instead, we always promote to the appropriate operator. (However, equality is currently not done correctly.)
* Enforce strict typing on ValueRanges: if you have a ValueRange for a float, the lower and upper MUST be floats, and so forth for integers.
The story begins in **torch/utils/_sympy/functions.py**. Here, I make some changes to how we represent certain operations in sympy expressions:
* FloorDiv now only supports integer inputs; to do float floor division, do a truediv and then a trunc. Additionally, we remove the divide out addition by gcd optimization, because sympy gcd is over fields and is willing to generate rationals (but rationals are bad for ValueRange strict typing).
* ModularIndexing, LShift, RShift now assert they are given integer inputs.
* Mod only supports integer inputs; eventually we will support FloatMod (left for later work, when we build out Sympy support for floating operations). Unfortunately, I couldn't assert integer inputs here, because of a bad interaction with sympy's inequality solver that is used by the offline solver
* TrueDiv is split into FloatTrueDiv and IntTrueDiv. This allows for us to eventually generate accurate code for Python semantics IntTrueDiv, which is written in a special way to preserve precision when the inputs are >= 2**53 beyond what first coercing the integer to floats and then doing true division.
* Trunc is split to TruncToFloat and TruncToInt.
* Round is updated to return a float, not an int, making it consistent with the round op handler in Inductor. To get Python-style conversion to int, we call TruncToInt on the result.
* RoundDecimal updated to consistently only ever return a float
* Add ToFloat for explicit coercion to float (required so we can enforce strict ValueRanges typing)
In **torch/__init__.py**, we modify SymInt and SymFloat to appropriately call into new bindings that route to these refined sympy operations. Also, we modify `torch.sym_min` and `torch.sym_max` to have promotion semantics (if one argument is a float, the return result is always a float), making them inconsistent with builtins.min/max, but possible to do type analysis without runtime information.
We also need to introduce some new op handlers in **torch/_inductor/ops_handler.py**:
* `to_int` for truncation to int64, directly corresponding to TruncToInt; this can be implemented by trunc and dtype, but with a dedicated handler it is more convenient for roundtripping in Sympy
* `int_truediv` for Python-style integer true division, which has higher precision than casting to floats and then running `truediv`
These changes have consequences. First, we need to make some administrative changes:
* Actually wire up these Sympy functions from SymInt/SymFloat in **torch/fx/experimental/sym_node.py**, including the new promotion rules (promote2)
* Add support for new Sympy functions in **torch/utils/_sympy/interp.py**, **torch/utils/_sympy/reference.py**
* In particular, in torch.utils._sympy.reference, we have a strong preference to NOT do nontrivial compute, instead, everything in ops handler should map to a singular sympy function
* TODO: I chose to roundtrip mod back to our Mod function, but I think I'm going to have to deal with the C/Python inconsistency this to fix tests here
* Add printer support for the Sympy functions in **torch/_inductor/codegen/common.py**, **torch/_inductor/codegen/cpp_utils.py**, **torch/_inductor/codegen/triton.py**. `int_truediv` and mixed precision equality is currently not implemented soundly, so we will lose precision in codegen for large values. TODO: The additions here are not exhaustive yet
* Update ValueRanges logic to use new sympy functions in **torch/utils/_sympy/value_ranges.py**. In general, we prefer to use the new Sympy function rather than try to roll things by hand, which is what was done previously for many VR analysis functions.
In **torch/fx/experimental/symbolic_shapes.py** we need to make some symbolic reasoning adjustments:
* Avoid generation of rational subexpressions by removing simplification of `x // y` into `floor(x / y)`. This simplification then triggers an addition simplification rule `(x + y) / c --> x / c + y / c` which is bad because x / c is a rational number now
* `_assert_bound_is_rational` is no more, we no longer generate rational bounds
* Don't intersect non-int value ranges with the `int_range`
* Support more sympy Functions for guard SYMPY_INTERP
* Assert the type of value range is consistent with the variable type
The new asserts uncovered necessary bug fixes:
* **torch/_inductor/codegen/cpp.py**, **torch/_inductor/select_algorithm.py**, **torch/_inductor/sizevars.py** - Ensure Wild/Symbol manually allocated in Inductor is marked `is_integer` so it's accepted to build expressions
* **torch/_inductor/utils.py** - make sure you actually pass in sympy.Expr to these functions
* **torch/_inductor/ir.py** - make_contiguous_strides_for takes int/SymInt, not sympy.Expr!
* **torch/export/dynamic_shapes.py** - don't use infinity to represent int ranges, instead use sys.maxsize - 1
Because of the removal of some symbolic reasoning that produced rationals, some of our symbolic reasoning has gotten worse and we are unable to simplify some guards. Check the TODO at **test/test_proxy_tensor.py**
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/126905
Approved by: https://github.com/xadupre, https://github.com/lezcano
At a high level, the idea behind this PR is:
* Make it clearer what the promotion and int/float rules for various Sympy operations are. Operators that previously were polymorphic over int/float are now split into separate operators for clarity. We never do mixed int/float addition/multiplication etc in sympy, instead, we always promote to the appropriate operator. (However, equality is currently not done correctly.)
* Enforce strict typing on ValueRanges: if you have a ValueRange for a float, the lower and upper MUST be floats, and so forth for integers.
The story begins in **torch/utils/_sympy/functions.py**. Here, I make some changes to how we represent certain operations in sympy expressions:
* FloorDiv now only supports integer inputs; to do float floor division, do a truediv and then a trunc. Additionally, we remove the divide out addition by gcd optimization, because sympy gcd is over fields and is willing to generate rationals (but rationals are bad for ValueRange strict typing).
* ModularIndexing, LShift, RShift now assert they are given integer inputs.
* Mod only supports integer inputs; eventually we will support FloatMod (left for later work, when we build out Sympy support for floating operations). Unfortunately, I couldn't assert integer inputs here, because of a bad interaction with sympy's inequality solver that is used by the offline solver
* TrueDiv is split into FloatTrueDiv and IntTrueDiv. This allows for us to eventually generate accurate code for Python semantics IntTrueDiv, which is written in a special way to preserve precision when the inputs are >= 2**53 beyond what first coercing the integer to floats and then doing true division.
* Trunc is split to TruncToFloat and TruncToInt.
* Round is updated to return a float, not an int, making it consistent with the round op handler in Inductor. To get Python-style conversion to int, we call TruncToInt on the result.
* RoundDecimal updated to consistently only ever return a float
* Add ToFloat for explicit coercion to float (required so we can enforce strict ValueRanges typing)
In **torch/__init__.py**, we modify SymInt and SymFloat to appropriately call into new bindings that route to these refined sympy operations. Also, we modify `torch.sym_min` and `torch.sym_max` to have promotion semantics (if one argument is a float, the return result is always a float), making them inconsistent with builtins.min/max, but possible to do type analysis without runtime information.
We also need to introduce some new op handlers in **torch/_inductor/ops_handler.py**:
* `to_int` for truncation to int64, directly corresponding to TruncToInt; this can be implemented by trunc and dtype, but with a dedicated handler it is more convenient for roundtripping in Sympy
* `int_truediv` for Python-style integer true division, which has higher precision than casting to floats and then running `truediv`
These changes have consequences. First, we need to make some administrative changes:
* Actually wire up these Sympy functions from SymInt/SymFloat in **torch/fx/experimental/sym_node.py**, including the new promotion rules (promote2)
* Add support for new Sympy functions in **torch/utils/_sympy/interp.py**, **torch/utils/_sympy/reference.py**
* In particular, in torch.utils._sympy.reference, we have a strong preference to NOT do nontrivial compute, instead, everything in ops handler should map to a singular sympy function
* TODO: I chose to roundtrip mod back to our Mod function, but I think I'm going to have to deal with the C/Python inconsistency this to fix tests here
* Add printer support for the Sympy functions in **torch/_inductor/codegen/common.py**, **torch/_inductor/codegen/cpp_utils.py**, **torch/_inductor/codegen/triton.py**. `int_truediv` and mixed precision equality is currently not implemented soundly, so we will lose precision in codegen for large values. TODO: The additions here are not exhaustive yet
* Update ValueRanges logic to use new sympy functions in **torch/utils/_sympy/value_ranges.py**. In general, we prefer to use the new Sympy function rather than try to roll things by hand, which is what was done previously for many VR analysis functions.
In **torch/fx/experimental/symbolic_shapes.py** we need to make some symbolic reasoning adjustments:
* Avoid generation of rational subexpressions by removing simplification of `x // y` into `floor(x / y)`. This simplification then triggers an addition simplification rule `(x + y) / c --> x / c + y / c` which is bad because x / c is a rational number now
* `_assert_bound_is_rational` is no more, we no longer generate rational bounds
* Don't intersect non-int value ranges with the `int_range`
* Support more sympy Functions for guard SYMPY_INTERP
* Assert the type of value range is consistent with the variable type
The new asserts uncovered necessary bug fixes:
* **torch/_inductor/codegen/cpp.py**, **torch/_inductor/select_algorithm.py**, **torch/_inductor/sizevars.py** - Ensure Wild/Symbol manually allocated in Inductor is marked `is_integer` so it's accepted to build expressions
* **torch/_inductor/utils.py** - make sure you actually pass in sympy.Expr to these functions
* **torch/_inductor/ir.py** - make_contiguous_strides_for takes int/SymInt, not sympy.Expr!
* **torch/export/dynamic_shapes.py** - don't use infinity to represent int ranges, instead use sys.maxsize - 1
Because of the removal of some symbolic reasoning that produced rationals, some of our symbolic reasoning has gotten worse and we are unable to simplify some guards. Check the TODO at **test/test_proxy_tensor.py**
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/126905
Approved by: https://github.com/xadupre, https://github.com/lezcano
We ran into a graph that looks something like the following, where we have 2 getitem calls to the same index (%getitem, %getitem_2 both query topk[0]):
```
graph():
%x : [num_users=1] = placeholder[target=x]
%topk : [num_users=3] = call_function[target=torch.ops.aten.topk.default](args = (%x, 2), kwargs = {})
%getitem : [num_users=1] = call_function[target=operator.getitem](args = (%topk, 0), kwargs = {})
%getitem_1 : [num_users=1] = call_function[target=operator.getitem](args = (%topk, 1), kwargs = {})
%getitem_2 : [num_users=1] = call_function[target=operator.getitem](args = (%topk, 0), kwargs = {})
%mul_tensor : [num_users=1] = call_function[target=torch.ops.aten.mul.Tensor](args = (%getitem, %getitem_2), kwargs = {})
%mul : [num_users=1] = call_function[target=torch.ops.aten.mul.Tensor](args = (%mul_tensor, 2), kwargs = {})
return (mul, getitem_1)
```
The duplicate getitem call gets created during a pass.. so there are a couple of solutions:
1. Change serializer to support the case of duplicate getitem calls
2. Change the pass so that it doesn’t produce duplicate getitem calls
3. Add a pass which dedups the getitem calls
As a framework, we should do 1 and 3 (through a CSE pass).
This PR implements solution 1. However, the serializer currently does some special handling for getitem nodes -- instead of directly serializing the getitem nodes, we serialize the output of the node that outputting a list of tensors (the %topk node in this example) into a list nodes for each output ([%getitem, %getitem_1]). This fails when we have duplicate getitem nodes to the same index (%getitem_2), since we do not record that duplicate getitem node anywhere. So, the solution this PR takes is that the serializer will deduplicate the getitem nodes (%getitem_2 will be replaced with %getitem). This would result in a sematically correct graph, but not necessarily node-to-node identical as the original fx graph.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127633
Approved by: https://github.com/ydwu4
This PR adds a registration function and a global registry for GraphModuleSerializer. After this PR, custom serialization methods can be done through registration instead of subclassing for ease of maintenance.
## Changes
- Add a test case where it injects custom op to test serialization.
- Add custom op handler
- Change allowed op for verifier
Co-authored-by: Zhengxu Chen <zhxchen17@outlook.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/126550
Approved by: https://github.com/zhxchen17
