mirror of https://github.com/llvm/torch-mlir
07d0645f64
Adaptive pooling ops can only be decomposed into their non-adaptive counterparts in trivial cases. For example, the current decomposition for AtenAdaptiveAvgPool1dOp in DecomposeComplexOps.cpp supports outSize = inSize (i.e., do literally nothing), and outSize = 1 (i.e., do a batched average). The reason adaptive pooling ops are difficult to lower to linalg is that they are not constantly strided. They are computed by taking an input tensor of shape (N, C, Hin), and an output size Hout, and computing the output tensor at position (n,c, h) in the following way: 1. compute st(h) = (h*Hin)//Hout 2. compute en(h) = 1 + ((h+1)*Hin -1)//Hout 3. apply a computation (max or avg) to the slice: INPUT[n, c, st(h):en(h)] The provided sample implementation (for ConvertAtenAdaptiveAvgPool1dOp) uses tensor.extract to access the input tensor inside the payload of a linalg generic op. This is likely an unattractive use of linalg generic ops, which is why I am asking for some more targeted feedback on the validity of this approach before attempting to support the many other adaptive pooling ops. Specifically: - Is the performance of this implementation bad enough to warrant targeting different dialects entirely? e.g. TMtensor/linalg ext/ etc. - If the provided implementation is of acceptable performance to the community, then is it permissable to remove the Adaptive pooling decompositions from DecomposeComplexOps.cpp? Based on the current structure of the -torch-decompose-complex-ops pass, it does not seem possible to only decompose the adaptive ops in special cases (it seems to get stuck in an infinite loop on a match failure). I would be happy to instead incorporate the case logic into the conversion directly, and remove the decompositions once they are rendered completely obsolete. As long as this approach is acceptable, I can clean up the implementation with some helper functions, and quickly add support for each of the remaining Adaptive pooling ops. |
||
|---|---|---|
| .. | ||
| TorchConversionToMLProgram | ||
| TorchOnnxToTorch | ||
| TorchToArith | ||
| TorchToLinalg | ||
| TorchToSCF | ||
| TorchToStablehlo | ||
| TorchToTMTensor | ||
| TorchToTensor | ||
| TorchToTosa | ||
| Utils | ||
| CMakeLists.txt | ||
| PassDetail.h | ||
| Passes.cpp | ||