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:
A re-land of D60006710.
Fixed TrainingIRToRunDecomp failures for test_tensor_attribute_zero_args and also a few re-tracability failures because run_decomposition does a retracing.
edit: also remove the eliminate_dead_code() in _unlift because of one onnx test failure:
a constant tensor attr was lifted as constant_tensor input but it's not used in the graph after aot_autograd due to a short cut in its decomposition. This causes the setattr to be removed by eliminate_dead_code but the graph signature still contains the name of that buffer, which causes an inconsitency between the transformed graph and ep's original signature after _unlift. And it seems that this has happened a few times where some nodes are accidentally removed and we're in an inconsistent state.
The alternative of removing it would be: every time we call elimiate_dead_code, we verify the consistency of the graph with 1. the graph before transformation and 2. all the meta datas but i think this deserves a complete design
edit 2: Also fix the inconsistency of graph signatures when param_constant is marked as lifted_tensor_constants but it's registered as parameters in the output of ep.module().
Differential Revision: D60532628
Pull Request resolved: https://github.com/pytorch/pytorch/pull/132307
Approved by: https://github.com/zhxchen17
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
Summary:
Reland of D60206382.
Suggested in https://github.com/pytorch/pytorch/issues/128394.
If there's an autocast context manager, the predispatch (strict) graph can look something like:
```
class <lambda>(torch.nn.Module):
def forward(self, x: "f32[1]"):
...
_enter_autocast = torch.amp.autocast_mode._enter_autocast('cuda', torch.bfloat16, True, None)
mm: "f32[8, 8]" = torch.ops.aten.mm.default(rand, rand_1); rand = rand_1 = None
_exit_autocast = torch.amp.autocast_mode._exit_autocast(_enter_autocast); _enter_autocast = None
return (mm_1,)
```
But the operator `torch.amp.autocast_mode._enter_autocast` is not a valid ATen op. We remove these nodes by turning autocast into a higher order operator and make a submodule for the blocks between `_enter_autocast` and `_exit_autocast`.
Some potential followup improvement:
1) Merge some of the duplicated logic with `replace_set_grad_with_hop_pass.py`
2) Check the current autocast status (any enabled? dtype?) and not create a submodule if the autocast args matches current autocast status.
Test Plan:
CI
```
buck2 run 'fbcode//mode/dev-nosan' fbcode//caffe2/test:test_export -- -r "test_predispatch_autocast"
buck2 run 'fbcode//mode/dev-nosan' fbcode//caffe2/test:test_export -- -r "test_predispatch_set_grad"
```
Verified that now we can export the llama model in gh issue 128394 and the gemma model in gh issue 131829 without error.
Differential Revision: D60770038
Pull Request resolved: https://github.com/pytorch/pytorch/pull/132677
Approved by: https://github.com/angelayi
Summary:
Suggested in https://github.com/pytorch/pytorch/issues/128394.
If there's an autocast context manager, the predispatch (strict) graph can look something like:
```
class <lambda>(torch.nn.Module):
def forward(self, x: "f32[1]"):
...
_enter_autocast = torch.amp.autocast_mode._enter_autocast('cuda', torch.bfloat16, True, None)
mm: "f32[8, 8]" = torch.ops.aten.mm.default(rand, rand_1); rand = rand_1 = None
_exit_autocast = torch.amp.autocast_mode._exit_autocast(_enter_autocast); _enter_autocast = None
return (mm_1,)
```
But the operator `torch.amp.autocast_mode._enter_autocast` is not a valid ATen op. We remove these nodes by turning autocast into a higher order operator and make a submodule for the blocks between `_enter_autocast` and `_exit_autocast`.
Some potential followup improvement:
1) Merge some of the duplicated logic with `replace_set_grad_with_hop_pass.py`
2) Check the current autocast status (any enabled? dtype?) and not create a submodule if the autocast args matches current autocast status.
Test Plan:
CI
```
parsh --build-flags fbcode//mode/dev-nosan fbcode//caffe2/test:test_export
run_tests("test_predispatch_autocast")
```
Reviewed By: angelayi
Differential Revision: D60206382
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131914
Approved by: https://github.com/angelayi
Summary:
Suggested in https://github.com/pytorch/pytorch/issues/128394.
If there's an autocast context manager, the predispatch (strict) graph can look something like:
```
class <lambda>(torch.nn.Module):
def forward(self, x: "f32[1]"):
...
_enter_autocast = torch.amp.autocast_mode._enter_autocast('cuda', torch.bfloat16, True, None)
mm: "f32[8, 8]" = torch.ops.aten.mm.default(rand, rand_1); rand = rand_1 = None
_exit_autocast = torch.amp.autocast_mode._exit_autocast(_enter_autocast); _enter_autocast = None
return (mm_1,)
```
But the operator `torch.amp.autocast_mode._enter_autocast` is not a valid ATen op. We remove these nodes by turning autocast into a higher order operator and make a submodule for the blocks between `_enter_autocast` and `_exit_autocast`.
Some potential followup improvement:
1) Merge some of the duplicated logic with `replace_set_grad_with_hop_pass.py`
2) Check the current autocast status (any enabled? dtype?) and not create a submodule if the autocast args matches current autocast status.
Test Plan:
CI
```
parsh --build-flags fbcode//mode/dev-nosan fbcode//caffe2/test:test_export
run_tests("test_predispatch_autocast")
```
Reviewed By: angelayi
Differential Revision: D60206382
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131914
Approved by: https://github.com/angelayi
Summary:
- moves logging functionalities into `torch/_export/db/logging.py` file.
- add a check in `_dynamo/eval_frame.py` to check for optional input and error out with `UnsupportedError`
- change the case name of `torch_sym_int` to `unsupported_operator`
- Check if the case name is registered in exportdb, if so, we give a link to the case in exportdb.
- TODO: add test
Test Plan:
CI
Running the example in https://pytorch.org/docs/main/generated/exportdb/index.html#optional-input gives the following error logging:
```
E0730 10:53:33.687000 4155538 torch/_dynamo/eval_frame.py:1086] Parameter y is optional with a default value of tensor([[-0.1633, 1.2414, -0.1071],
E0730 10:53:33.687000 4155538 torch/_dynamo/eval_frame.py:1086] [-0.1936, -0.9425, -0.0824]])
E0730 10:53:33.688000 4155538 torch/export/_trace.py:1043] See optional_input in exportdb for unsupported case. https://pytorch.org/docs/main/generated/exportdb/index.html#optional-input
......
File "/data/users/shangdiy/fbsource/buck-out/v2/gen/fbcode/389acaeb40d57230/tutorials/pytorch/nntest/__torchtest__/torchtest#link-tree/torch/_dynamo/eval_frame.py", line 1091, in produce_matching
raise Unsupported(
torch._dynamo.exc.Unsupported: Tracing through optional input is not supported yet
```
It also logs a `export.error.classified` event in Scuba.
Reviewed By: zhxchen17
Differential Revision: D60427208
Pull Request resolved: https://github.com/pytorch/pytorch/pull/132420
Approved by: https://github.com/zhxchen17
Summary:
Fixes https://github.com/pytorch/pytorch/issues/130379.
The original error is verifier finds that the placeholder nodes' meta[''val"] are missing in subgraph of WrapSetGradEnabled hop.
In this PR, we fixed it by re-ordering the replace_set_grad_with_hop_pass with lift_constant_tensor pass because only after lift_constant_pass, all the constant attrs start to have meta["val"].
Test Plan: buck2 test test:test_export -- -r "test_setgrad_lifted_tensor"
Differential Revision: D60244935
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131787
Approved by: https://github.com/yushangdi
Suggests fixes for data-dependent errors in non-strict export.
Any data-dependent error has an unresolved condition on unbacked symints. A mechanizable strategy for fixing such errors, which this PR enables, is to "bash" them using `torch._check()`s. For each error we suggest using `torch._check()` on the condition or its negation. The user selects and copy-pastes the suggested fix and continues.
For example, here's an existing data-dependent error message with the suffix following `<snip>...</snip>` added by this PR:
```
Could not guard on data-dependent expression Eq(u2, u1) (unhinted: Eq(u2, u1)). (Size-like symbols: u1)
<snip>...</snip>
User code:
File "test/export/test_export.py", line 1944, in forward
return r.view(items[0], items[2])
Suggested fixes (please choose one of the following):
1. torch._check(items[2] == r.shape[1])
2. torch._check(items[2] != r.shape[1])"
```
Tests in this PR illustrate this workflow, by taking common examples of data-dependent errors and bashing them until success, purely based on suggested fixes. In particular, we test this workflow on the "puzzlers" in https://www.internalfb.com/intern/anp/view/?id=5330476 (thanks @ezyang).
In terms of implementation, we focus on non-strict mode, where we can intercept torch function calls to install a handler that walks up the stack from the error, finding the closest non-torch frame and inspecting its locals for symints appearing in the error. The suggested fixes then access these symints through the local variables so that they can be (a) easily understood by the user (b) directly added to the code.
Implementing this idea in strict mode is follow-up work—we have already investigated what it would take, and decided to separate it out of this PR for reasons described next.
It's not too hard to map symints to locals in Dynamo (although it needs to happen elsewhere, i.e., intercepting torch function calls won't work). However, unfortunately this doesn't seem to be enough; the graph modules created by Dynamo when going through AOTAutograd can raise further data-dependent errors in some cases, and thus we need yet another mechanism to map symints to locals for graph modules, via captured source-level metadata and FX node walking. This latter component will require some care to build properly, or we might conclude it is altogether unnecessary and fix Dynamo instead.
Differential Revision: D56867432
Pull Request resolved: https://github.com/pytorch/pytorch/pull/125378
Approved by: https://github.com/ezyang
Summary:
Dynamo doesn't track whether buffers are `persistent`. This led to some ugly code where we would mark buffers as always persistent when creating signatures, then later check whether the buffers were not in the state dict to infer whether they were non-persistent, and use this to fix up the signature.
This PR instead defines a utility to look up all the non-persistent buffers registered inside a module (this information is recorded in a private `_non_persistent_buffers_set` module attribute), and uses it to (a) correctly set the persistent flag on buffers when creating signatures (b) transfer this information to a Dynamo-traced graph module, which then causes non-persistent buffers to (correctly) not show up in the state dict.
Test Plan: existing tests + new case with non-persistent buffer in nested module
Differential Revision: D60224656
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131756
Approved by: https://github.com/zhxchen17, https://github.com/ydwu4
Summary:
This pr fixes all the places in strict export stack where the output node's meta is not preserved correctly. However, we're getting a new error for the test we intend to fix: `buck2 run caffe2/test/quantization:test_quantization -- -r "test_re_export_preserve_handle"`:
The `get_attr` nodes has wrong metadata. I guess there are more things need to be fixed to get it working but it's beyond the scope of this PR.
Test Plan: buck2 run caffe2/test/quantization:test_quantization -- -r "test_re_export_preserve_handle"
Differential Revision: D60198221
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131706
Approved by: https://github.com/yushangdi
Summary:
When importing `_trace.py`, put `torch._dynamo.exc.Unsupported` in the global variable ``_ALLOW_LIST`` can cause import to ``export/_trace.py`` to fail with error:
ValueError: Artifact name: 'graph_breaks' not registered, please call register_artifact('graph_breaks') in torch._logging.registrations.
The error is directly raise on line `graph_breaks_log = torch._logging.getArtifactLogger(__name__, "graph_breaks")` in `_dynamo/exc.py`. I've checked that ``register_artifact('graph_breaks')`` does already exist in torch._logging.registrations.
Explicitly call `import torch._logging` doesn't fix the issue.
(see T196719676)
We move ``_ALLOW_LIST`` to be a local variable.
Test Plan:
buck2 test 'fbcode//mode/opt' fbcode//aiplatform/modelstore/publish/utils/tests:fc_transform_utils_test -- --exact 'aiplatform/modelstore/publish/utils/tests:fc_transform_utils_test - test_serialized_model_for_disagg_acc (aiplatform.modelstore.publish.utils.tests.fc_transform_utils_test.PrepareSerializedModelTest)'
buck2 test 'fbcode//mode/opt' fbcode//aiplatform/modelstore/publish/utils/tests:fc_transform_utils_test -- --exact 'aiplatform/modelstore/publish/utils/tests:fc_transform_utils_test - test_serialized_test_dsnn_module (aiplatform.modelstore.publish.utils.tests.fc_transform_utils_test.PrepareSerializedModelTest)'
Differential Revision: D60136706
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131523
Approved by: https://github.com/zhxchen17
Summary:
Previously it was unclear what `_convert_input_to_fake` actually does (used in strict), and in particular how it is different from `make_fake_inputs` (used in non-strict).
This PR splits that function to work purely on user inputs, then renames it to `extract_fake_inputs` and adds a comment clarifying what it does—namely, it extracts fake inputs from a given graph module instead of "converting inputs to fake inputs" (as suggested by the current name) or "making fake inputs" (as happens in non-strict, where no tracing has taken place yet).
The remainder of that function used to also fakify params and buffers. It turns out that this part is identical to what happens in non-strict, hence we also pull `make_fake_inputs` out from `non_strict_utils` into `_trace`, merge it with another util, and make both modes call it.
Test Plan: existing tests
Differential Revision: D60084442
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131421
Approved by: https://github.com/zhxchen17
Summary:
- Log export errors to Scuba and mark them with "classified" and "unclassified"
- Classify errors by exception type (ALLOW_LIST) and a `case_name` attribute
- Add `case_name` for some exceptions.
Test Plan:
Running the code below logs a classified error to `torch_export_usage` table in Scuba.
```
import torch
from torch._export.db.case import SupportLevel
class TorchSymMin(torch.nn.Module):
"""
torch.sym_min operator is not supported in export.
"""
def forward(self, x):
return x.sum() + torch.sym_min(x.size(0), 100)
example_args = (torch.randn(3, 2),)
tags = {"torch.operator"}
support_level = SupportLevel.NOT_SUPPORTED_YET
model = TorchSymMin()
torch.export.export(model, example_args)
``
Differential Revision: D59981459
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131327
Approved by: https://github.com/zhxchen17
Summary:
This diff reverts D59561509
D59561509: [FX][export] DCE pass, check schema for node impurity (#130395) by yushangdi causes the following test failure:
Tests affected:
- [cogwheel:cogwheel_mtia_cmf_m5_shrunk_test#test_flow_with_verification](https://www.internalfb.com/intern/test/844425041436985/)
Here's the Multisect link:
https://www.internalfb.com/multisect/6533402
Here are the tasks that are relevant to this breakage:
T191383430: 10+ tests unhealthy for ads_mtia_inference
The backout may land if someone accepts it.
If this diff has been generated in error, you can Commandeer and Abandon it.
Test Plan: NA
Differential Revision: D60029318
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131341
Approved by: https://github.com/angelayi
Fixed TrainingIRToRunDecomp failures for test_tensor_attribute_zero_args and also a few re-tracability failures because run_decomposition does a retracing.
**edit:** also remove the eliminate_dead_code() in _unlift because of one onnx test failure:
a constant tensor attr was lifted as constant_tensor input but it's not used in the graph after aot_autograd due to a short cut in its decomposition. This causes the setattr to be removed by eliminate_dead_code but the graph signature still contains the name of that buffer, which causes an inconsitency between the transformed graph and ep's original signature after _unlift. And it seems that this has happened a few times where some nodes are accidentally removed and we're in an inconsistent state.
The alternative of removing it would be: every time we call elimiate_dead_code, we verify the consistency of the graph with 1. the graph before transformation and 2. all the meta datas but i think this deserves a complete design.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130990
Approved by: https://github.com/pianpwk
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: Adds non-strict implementation of training IR export. Any expected non-strict training IR failures are also either existing strict training IR or non-strict failures (no new failures added). 4 strict training IR failures also resolved.
Refraining from unifying export/export_for_training, per @ydwu4's feedback :)
Test Plan: added test_export_training_ir_to_run_decomp_non_strict.py for non-strict training IR
Differential Revision: D59349454
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130062
Approved by: https://github.com/ydwu4, https://github.com/zhxchen17
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
Recently we decided to split export IR into two different IRs (training vs inference). In the inference IR, one major change we decided to introduce was we wanted to keep the composite ops that user specified in the IR. This PR does that by overriding the CompositeImplicitAutograd decomp in export inference path.
Differential Revision: [D58701607](https://our.internmc.facebook.com/intern/diff/D58701607)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/128077
Approved by: https://github.com/bdhirsh
Summary: Today meta['val'] on placeholder nodes doesn't preserve the consistent requires_grad information with the original inputs. Seems there's no easy way to fix this directly at proxy tensor layer. This is useful for reexporting joint graph.
Test Plan: test_preserve_requires_grad_placeholders
Differential Revision: D58555651
Pull Request resolved: https://github.com/pytorch/pytorch/pull/128656
Approved by: https://github.com/tugsbayasgalan
Summary: When we export already traced module, it seems to be modifying some global state causing the traced modules to fail to run. For now, we are only logging for test cases, so it is probs ok to trace fresh copy to be used in export for now.
Test Plan: CI
Differential Revision: D57983518
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127577
Approved by: https://github.com/pianpwk
With the current state of export's dynamic shapes, we struggle with guards and constraints that are beyond the current dynamic shapes language, expressed with dims and derived dims. While we can compile and guarantee correctness for guards within the current language (e.g. min/max ranges, linear relationships, integer divisibility) we struggle to dynamically compile guards which extend beyond that.
For these "complex" guards, we typically do either of the following: 1) raise a constraint violation error, along the lines of "not all values of <symbol> in the specified range satisfy <guard>", with or without suggested fixes, 2) specialize to the provided static values and suggest removing dynamism, or 3) fail compilation due to some arbitrary unsupported case. Previous [work](https://github.com/pytorch/pytorch/pull/124949) went towards resolving this by disabling forced specializations, instead allowing the user to fail at runtime with incorrect inputs.
In this PR, relying on [hybrid backed-unbacked symints](https://github.com/pytorch/pytorch/issues/121749), [deferred runtime asserts](https://github.com/pytorch/pytorch/blob/main/torch/fx/passes/runtime_assert.py), and the function [_is_supported_equivalence()](d7de4c9d80/torch/fx/experimental/symbolic_shapes.py (L1824)), we add a flag `_allow_complex_guards_as_runtime_asserts` which allows the user to compile exported programs containing these guards and maintain dynamism, while adding correctness checks as runtime assertions in the graph.
Hybrid backed-unbacked symints allow us to easily bypass "implicit" guards emitted from computation - guards that we ~expect to be true. Popular examples revolve around reshapes:
```
# reshape
def forward(self, x, y): # x: [s0, s1], y: [s2]
return x.reshape([-1]) + y # guard s0 * s1 = s2
This leads to the following exported program
class GraphModule(torch.nn.Module):
def forward(self, x: "f32[s0, s1]", y: "f32[s2]"):
sym_size_int: "Sym(s2)" = torch.ops.aten.sym_size.int(y, 0)
mul: "Sym(-s2)" = -1 * sym_size_int; sym_size_int = None
sym_size_int_1: "Sym(s0)" = torch.ops.aten.sym_size.int(x, 0)
sym_size_int_2: "Sym(s1)" = torch.ops.aten.sym_size.int(x, 1)
mul_1: "Sym(s0*s1)" = sym_size_int_1 * sym_size_int_2; sym_size_int_1 = sym_size_int_2 = None
add: "Sym(s0*s1 - s2)" = mul + mul_1; mul = mul_1 = None
eq: "Sym(Eq(s0*s1 - s2, 0))" = add == 0; add = None
_assert_scalar = torch.ops.aten._assert_scalar.default(eq, "Runtime assertion failed for expression Eq(s0*s1 - s2, 0) on node 'eq'"); eq = None
view: "f32[s0*s1]" = torch.ops.aten.view.default(x, [-1]); x = None
add_1: "f32[s0*s1]" = torch.ops.aten.add.Tensor(view, y); view = y = None
return (add_1,)
```
Another case is symbol divisibility:
```
def forward(self, x): # x: [s0, s1]
return x.reshape([-1, x.shape[0] - 1]) # Eq(Mod(s0 * s1, s0 - 1), 0)
```
Applying deferred runtime asserts also helps dynamic compilation for "explicit" complex guards that typically cause problems for export. For example we can generate runtime asserts for not-equal guards, and complex conditions like the following:
```
class Foo(torch.nn.Module):
def forward(self, x, y):
# check that negation of first guard also shows up as runtime assertion
if x.shape[0] == y.shape[0]: # False
return x + y
elif x.shape[0] == y.shape[0] ** 3: # False
return x + 2, y + 3
elif x.shape[0] ** 2 == y.shape[0] * 3: # True
return x * 2.0, y * 3.0
```
For the above graph we will generate 3 runtime assertions: the negation of the first 2, and the 3rd condition as a guard.
One additional benefit here over the current state of exported programs is that this adds further correctness guarantees - previously with explicit complex guards, if compilation succeeded, the guards would be ignored at runtime, treated as given.
As shown above, the runtime asserts appear as math ops in the graph, generated by the sympy interpreter, resulting in an _assert_scalar call. There is an option to avoid adding these asserts into the graph, by setting `TORCH_DYNAMO_DO_NOT_EMIT_RUNTIME_ASSERTS=1`. This results in the "original" computation graph, with dynamism, and any incorrect inputs will fail on ops during runtime. Further work could go into prettifying the printer, so the majority of the graph isn't guard-related.
Ideally this PR would subsume and remove the recently added [_disable_forced_specializations](https://github.com/pytorch/pytorch/pull/124949) flag, but that flag still handles one additional case of specialization: single-variable equalities where the symbol is solvable for a concrete value: see this [PR](https://github.com/pytorch/pytorch/pull/126925)
This PR doesn't change any behavior around data-dependent errors/unbacked symints yet, that could be further work.
NOTE: will take naming change suggestions for the flag :)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127129
Approved by: https://github.com/avikchaudhuri