# Problem
Inductor implicitly upcasts certain rank-0 kernel arguments from float16 to float32. Currently, this happens only on the `"cpu"` device, which appears to be related to float16 support in CPU Triton. However, it can also affect the behavior of GPU kernels, when a model contains tensors from multiple devices. Upcasting may be undesirable on some platforms, so users can typically disable it with the `config.triton.codegen_upcast_to_fp32` flag. However, this flag was not respected by the rank-0 kernel argument codepath.
Through an improbable series of events, float32 upcasting caused an internal model to fail compilation on MTIA. (Internal reviewers see T242444110.)
# Fix
If `config.triton.codegen_upcast_to_fp32` evaluates to `False`, cast the kernel argument to the original dtype.
# Test plan
Added a new CI test checking for the downcast iff the config flag is false. The test mixes GPU and CPU tensors to generate a GPU kernel with the implicit float32 upcast and explicit float16 downcast.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/166118
Approved by: https://github.com/jfix71, https://github.com/jansel, https://github.com/kundaMwiza
By allowing the options classes (`BlockPtrOptions`/`TensorDescriptorOptions`) to be overridden in `TritonKernel`, subclasses with custom behaviour can be used in place of them, which provides greater flexibility.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/165899
Approved by: https://github.com/jansel
Summary: For D84399286, failing ads ne deterministic tests now. These tests are especially brittle with subtle bitwise numerics changes. Will reenable for fbcode once e2e validation tests are performed
Test Plan: N/A
Differential Revision: D84514361
Pull Request resolved: https://github.com/pytorch/pytorch/pull/165328
Approved by: https://github.com/izaitsevfb
### Implementation of #151705
This PR introduces the initial implementation of native `tl.dot` support in Inductor, with the goal of generating Triton matmul kernels directly—without relying on predefined templates.
To avoid complexity and ease the review process, I plan to split this work into two phases as outlined in #151705:
1. **Basic support** (this PR)
2. **Lazy broadcasting** for optimal performance (future PR)
### Summary of This PR
This PR implements the basic functionality. It does **not** include lazy broadcasting, so the generated kernels may involve explicit `tl.reshape` and `tl.trans` operations before calling `tl.dot`, which introduces some overhead.
### Notable Changes
1. Adds a new config flag: `config.triton.enable_native_matmul`
2. Introduces a new `ops.dot` IR node in Inductor and lowers `aten.mm` and `aten.bmm` to it when native matmul is enabled
3. Enforces tililng suitable for matmul when the native matmul flag is enabled
4. Implements code generation for `ops.dot`
5. Adds Triton autotuning heuristics: for now, I’ve copied the configuration from the existing matmul templates. However, this may not be optimal—it currently takes a long time to tune, and I think there must be a better way to tackle this.
@eellison @jansel @PaulZhang12 @shunting314
Pull Request resolved: https://github.com/pytorch/pytorch/pull/157743
Approved by: https://github.com/jansel
Verify the deterministic mode with torch.compile benchmark scripts.
Here is what my testing script does (pasted in the end):
- run a model in default mode, save it's result
- run the model again in default mode, but distort the benchmarking results. Compare it with the saved result.
- Do the above again in deterministic mode.
I tried to test a few modes
- BertForMaskedLM and GoogleFnet: I can repro the numeric change by distorting the benchnmark result in the default mode. The non-determinism is gone in the deterministic mode
- DistillGPT2: I can not repro the numeric change by distorting the benchmarking result in the default mode. It does not surprise me much. Reduction order change does not always cause numeric change.
```
model=GoogleFnet
export TORCHINDUCTOR_WRITE_ARE_DETERMINISTIC_ALGORITHMS_ENABLED=0
export TORCHINDUCTOR_FORCE_DISABLE_CACHES=1 # disable autotune cache
export TORCHINDUCTOR_FX_GRAPH_REMOTE_CACHE=0
export TORCHINDUCTOR_FX_GRAPH_CACHE=0
export TORCHINDUCTOR_CACHE_DIR=/tmp/torchinductor_shunting/
export TORCHINDUCTOR_BENCHMARK_KERNEL=1
export TORCHINDUCTOR_UNIQUE_KERNEL_NAMES=1
export INDUCTOR_TEST_DISABLE_FRESH_CACHE=1
# Non deterministic mode
# --float32 rather than --amp to make it easier to repro non-deterministic
echo "Save results for non-deterministic mode"
python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --save-model-outputs-to=/tmp/saved-non-deterministic.pkl
echo "Compare results with distorted benchmarking in non-deterministic mode"
TORCHINDUCTOR_DISTORT_BENCHMARKING_RESULT=inverse python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --compare-model-outputs-with=/tmp/saved-non-deterministic.pkl
echo "Save results for deterministic mode"
TORCHINDUCTOR_DETERMINISTIC=1 python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --save-model-outputs-to=/tmp/saved-deterministic.pkl
echo "Compare results with distorted benchmarking in deterministic mode"
TORCHINDUCTOR_DETERMINISTIC=1 TORCHINDUCTOR_DISTORT_BENCHMARKING_RESULT=inverse python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --compare-model-outputs-with=/tmp/saved-deterministic.pkl
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/164904
Approved by: https://github.com/jansel, https://github.com/v0i0
Verify the deterministic mode with torch.compile benchmark scripts.
Here is what my testing script does (pasted in the end):
- run a model in default mode, save it's result
- run the model again in default mode, but distort the benchmarking results. Compare it with the saved result.
- Do the above again in deterministic mode.
I tried to test a few modes
- BertForMaskedLM and GoogleFnet: I can repro the numeric change by distorting the benchnmark result in the default mode. The non-determinism is gone in the deterministic mode
- DistillGPT2: I can not repro the numeric change by distorting the benchmarking result in the default mode. It does not surprise me much. Reduction order change does not always cause numeric change.
```
model=GoogleFnet
export TORCHINDUCTOR_WRITE_ARE_DETERMINISTIC_ALGORITHMS_ENABLED=0
export TORCHINDUCTOR_FORCE_DISABLE_CACHES=1 # disable autotune cache
export TORCHINDUCTOR_FX_GRAPH_REMOTE_CACHE=0
export TORCHINDUCTOR_FX_GRAPH_CACHE=0
export TORCHINDUCTOR_CACHE_DIR=/tmp/torchinductor_shunting/
export TORCHINDUCTOR_BENCHMARK_KERNEL=1
export TORCHINDUCTOR_UNIQUE_KERNEL_NAMES=1
export INDUCTOR_TEST_DISABLE_FRESH_CACHE=1
# Non deterministic mode
# --float32 rather than --amp to make it easier to repro non-deterministic
echo "Save results for non-deterministic mode"
python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --save-model-outputs-to=/tmp/saved-non-deterministic.pkl
echo "Compare results with distorted benchmarking in non-deterministic mode"
TORCHINDUCTOR_DISTORT_BENCHMARKING_RESULT=inverse python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --compare-model-outputs-with=/tmp/saved-non-deterministic.pkl
echo "Save results for deterministic mode"
TORCHINDUCTOR_DETERMINISTIC=1 python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --save-model-outputs-to=/tmp/saved-deterministic.pkl
echo "Compare results with distorted benchmarking in deterministic mode"
TORCHINDUCTOR_DETERMINISTIC=1 TORCHINDUCTOR_DISTORT_BENCHMARKING_RESULT=inverse python benchmarks/dynamo/huggingface.py --backend inductor --float32 --accuracy --only $model --training --disable-cudagraphs --compare-model-outputs-with=/tmp/saved-deterministic.pkl
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/164904
Approved by: https://github.com/jansel, https://github.com/v0i0
ghstack dependencies: #164801, #164532
Add a deterministic mode to skip the on device benchmarking that we know should affect numeric. This include
- pad-mm
- dynamic rblock scaling
- template autotuning
- coordinate descent tuning for reduction
- reduction config autotuning in CachingAutotuner. For reduction both RBLOCK, num_warps should affect numeric. XBLOCK does not. We can still autotune XBLOCK for reductions.
- benchmarking for computation communication reordering pass
The mode definitely has perf hit.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/163589
Approved by: https://github.com/v0i0
Fixes#163702.
This fixes 2 issues:
1. The value may inconsistently be a shape or string. This normalizes to handle both of these.
2. 1D shapes should not transpose data. This fixes the order of operations to prevent this.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/163966
Approved by: https://github.com/eellison
Summary:
- Move the `provenance_level` flag check to inside the `set_kernel_post_grad_provenance_tracing` call to simply the code
- Move the `set_kernel_post_grad_provenance_tracing` call and `write_provenance_debug_handle` call to `codegen_comment`.
- If some `call_kernel` call sites don't have a proceeding `codegen_comment` call, add one. Now all `call_kernel` call sites are accompanied with a `codegen_comment` call.
- Add a `codegen_comment` method to BaseScheduling and remove the noop `codegen_comment` method in Scheduling
- Remove `debug_handle` from `call_kernel`.
Test Plan:
CI
```
buck run @//mode/opt-split-dwarf fbcode//caffe2/test/inductor:provenance_tracing
```
Differential Revision: D82839271
Pull Request resolved: https://github.com/pytorch/pytorch/pull/163378
Approved by: https://github.com/angelayi
Summary: Enables support for epilogue subtiling in the blackwell ws template. This requires the ability to call `store_output` twice in the same kernel and reuse the same tensor descriptor across allocations.
Test Plan:
Tested with test_max_autotune.py on a Blackwell server.
Rollback Plan:
Differential Revision: D82610077
Pull Request resolved: https://github.com/pytorch/pytorch/pull/163145
Approved by: https://github.com/eellison