## `VariableTracker::build()` hides the Builders
### The problem
In the current code, creating a `VariableTracker` involves choosing one of two `Builder` classes and either calling a method, or calling a constructor that creates an object that you immediately call, [like this](083c9149b7/torch/_dynamo/variables/functions.py (L761-L768)).
Variations on this code are repeated in many places.
More, the `Builder` classes have a lot of dependencies, so they have to be loaded late in the whole import process to avoid circular imports, so they end up being repeatedly imported at local scope.
### The solution
In this commit, the import from `builder` and the logic of choosing and calling the Builder class are hidden in a single static factory method, `VariableTracker.build()`, easier to reason about and to import.
This commit net lowers the total lines of code by over 150 lines by removing repetitive logic and unnecessary local imports.
**CHANGES:** Originally the name of the static method was `VariableTracker.create()` but a static method on a derived class, `LazyVariableTracker.create()` now exists with a different signature that's irreconcilable, so the new static method was renamed to `VariableTracker.build()`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/135714
Approved by: https://github.com/jansel
Cleanup:
1/ We do not need to unwrap_subclasses() in freezing wrapper, as it will be wrapped by AOTD wrappers which inclused SubclassesWrapper
2/ No need to use weakreferences for unwrapped list, dynamo optimizers need to clean unwrapped list along with original params_flat.
Verfified fbcode tests compiled_optimizers
Differential Revision: [D63393651](https://our.internmc.facebook.com/intern/diff/D63393651)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/136549
Approved by: https://github.com/bdhirsh
Fixes#115607
We were missing guards when the grads were set to `None`. So if we compiled the optimizer with grads set to their proper value, and then with the grads set to `None` we'd continuously run the `None` version because all of the guards would pass and it would be ordered before the correct version in the cache.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/121291
Approved by: https://github.com/Skylion007, https://github.com/anijain2305
This enables the new way of writing guards for dicts. Before we were
doing things like
```
L['self'].param_groups[0][___dict_keys_getitem(L['self'].param_groups[0], 0)][3] is L['self'].param_groups[0]['params'][3]
```
without knowing whether `L['self'].param_groups[0][___dict_keys_getitem(L['self'].param_groups[0], 0)]` was a list.
On a different note, I'll probably write a pass to recover the previous
way to place guards on dicts via something like `DICT_KEYS` as an
optimisation, as it seems relevant for optimisers.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/117983
Approved by: https://github.com/mlazos
ghstack dependencies: #117982, #118098
The original motivation for MYPYINDUCTOR was a faster type checking configuration that only checked a subset of files. With the removal of `follow_imports = ignore`, we are now able to use dmypy to do fast incremental typechecking, eliminating the need for this.
Perhaps erroneously, when I tee'ed up this PR I elected to delete the `follow_imports = skip` designations in the mypy-inductor.ini. This lead to a number of extra type error suppressions that I manually edited. You will need to review.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/118432
Approved by: https://github.com/Skylion007
ghstack dependencies: #118414, #118418
We split install_global_once into two APIs:
- `install_global_by_id(prefix, value) -> name`: installs a global if it hasn't
been installed yet
- `install_global(prefix, value) -> name`: always installs the global (and
generates a unique name for it)
Then, we refactor most callsites of `install_global_unsafe` to one of
the previous. Some callsites cannot be refactored because we create the
global name first, do a lot of stuff with it, and then install it.
This fixes more test flakiness.
Test Plan:
- Existing tests; I can't reliably repro the flakiness
Pull Request resolved: https://github.com/pytorch/pytorch/pull/118100
Approved by: https://github.com/ezyang, https://github.com/mlazos
1. Removes calls to `replace_all` and `clone` and makes VTs mutable.
2. Properly handles Tuple Iterator mutation. Previously TupleIterator variables would only be properly reconstructed if they were advanced at least once in a frame. On calls to `next`, the source information would be lost (due to constructing a new iterator without using builder), which would ensure that during codegen the variable would be reconstructed from scratch. Now that VTs are mutated, the source is never lost, so we need to properly track mutation and handle it by replaying calls to `next` at the end of the modified bytecode.
3. Added test for checking iadd side effects, this was missing in our unit test coverage.
4. Fixed two incorrect sources, DelayGraphBreakVariable, and UserMethodVariable both relied on setting the source to AttrSource(parent, name) at the callsite of `var_getattr`.
5. Fixed a bug in inplace adding for lists, it would set the resulting VariableTracker's source to `None` which would utilize a different reconstruct path in codegen. Now this is handled explicitly by reconstructing vars when allow_cache=`False`, so that during side effect replay, the mutated var is correctly updated.
In subsequent PRs:
* Refactoring side effect tracking to be significantly simpler (I think we only need an `is_modified` flag)
* Refactor `next_variables` iterator to match the signature of `next`
* Remove all references to `options` in the code
* Refactor VTs representing mutable collections to implement their own mutation update handling
* Remove clone and/or make it specific to lists for creating slices
* Add mutation tracking/replay for sets
* Add mutation tracking/replay for iter.py
* Removing setting source in builder (it's set at the top level after a var is returned)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113725
Approved by: https://github.com/jansel
