Nicolas Vasilache 04ba475e85 [mlir][Vector] Add a rewrite pattern for better low-precision ext(bit… (#66648) ... …cast) expansion This revision adds a rewrite for sequences of vector `ext(bitcast)` to use a more efficient sequence of vector operations comprising `shuffle` and `bitwise` ops. Such patterns appear naturally when writing quantization / dequantization functionality with the vector dialect. The rewrite performs a simple enumeration of each of the bits in the result vector and determines its provenance in the source vector. The enumeration is used to generate the proper sequence of `shuffle`, `andi`, `ori` with shifts`. The rewrite currently only applies to 1-D non-scalable vectors and bails out if the final vector element type is not a multiple of 8. This is a failsafe heuristic determined empirically: if the resulting type is not an even number of bytes, further complexities arise that are not improved by this pattern: the heavy lifting still needs to be done by LLVM.		2023-09-18 19:02:46 +02:00
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mlir	[mlir][Vector] Add a rewrite pattern for better low-precision ext(bit… (#66648)	2023-09-18 19:02:46 +02:00
mlir-c	[mlir] Add Python bindings for DenseResourceElementsAttr. (#66319)	2023-09-14 18:45:29 -07:00