[Mlir-commits] [mlir] [mlir][XeGPU][Transform] Add gather/scatter coalescing analysis. (PR #201684)

[Jianhui Li]

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+//===- XeGPUContiguityAnalysis.cpp - Offset contiguity analysis ---------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the contiguity analysis. It computes, for a memory
+// operation (i.e., `xegpu.load` / `xegpu.store`), how many elements are
+// contiguous along the innermost offsets dimension, and stamps that count as an
+// attribute on the op. The analysis is a small XeGPU-local
+// axis-info dataflow tracking per-axis `contiguity`, `constancy`, and
+// `divisibility`; the stamped value is the inner-dim `contiguity`.
+//
+// Contiguity is a target-independent property of the offsets.
+//
+// The analysis tracks per-axis information for vectors of integer / index
+// type at any rank, against the innermost dimension.
+//
+// The analysis gets it's inspiration from the Triton Axis info analysis.
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Analysis/DataFlow/DeadCodeAnalysis.h"
+#include "mlir/Analysis/DataFlow/SparseAnalysis.h"
+#include "mlir/Analysis/DataFlowFramework.h"
+#include "mlir/Dialect/Arith/IR/Arith.h"
+#include "mlir/Dialect/MemRef/IR/MemRef.h"
+#include "mlir/Dialect/Vector/IR/VectorOps.h"
+#include "mlir/Dialect/XeGPU/IR/XeGPU.h"
+#include "mlir/Dialect/XeGPU/Transforms/Passes.h"
+#include "mlir/Dialect/XeGPU/Transforms/Transforms.h"
+#include "mlir/Dialect/XeGPU/Utils/XeGPUUtils.h"
+#include "mlir/IR/BuiltinAttributes.h"
+#include "mlir/IR/BuiltinTypes.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/Support/MathExtras.h"
+#include <numeric>
+#include <optional>
+
+#define DEBUG_TYPE "xegpu-coalesce-gather-scatter"
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Jianhui-Li wrote:

xegpu-coalesce-gather-scatter -> xegpu-contiguity-analysis to match file name. 

https://github.com/llvm/llvm-project/pull/201684