[Mlir-commits] [mlir] [mlir][xegpu] Refine layout assignment in XeGPU SIMT distribution. (PR #142687)

[Charitha Saumya]

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@@ -0,0 +1,955 @@
+//===- XeGPULayoutPropagate.cpp - XeGPU Layout Propagation ------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Analysis/DataFlow/ConstantPropagationAnalysis.h"
+#include "mlir/Analysis/DataFlow/DeadCodeAnalysis.h"
+#include "mlir/Analysis/DataFlow/SparseAnalysis.h"
+#include "mlir/Analysis/DataFlowFramework.h"
+#include "mlir/Dialect/GPU/IR/GPUDialect.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/Utils/XeGPUUtils.h"
+#include "mlir/IR/Attributes.h"
+#include "mlir/IR/Builders.h"
+#include "mlir/IR/BuiltinAttributes.h"
+#include "mlir/IR/BuiltinTypes.h"
+#include "mlir/IR/Operation.h"
+#include "mlir/IR/Value.h"
+#include "mlir/IR/Visitors.h"
+#include "mlir/Interfaces/ControlFlowInterfaces.h"
+#include "mlir/Interfaces/FunctionInterfaces.h"
+#include "mlir/Support/LLVM.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/TypeSwitch.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/InterleavedRange.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace mlir {
+namespace xegpu {
+#define GEN_PASS_DEF_XEGPULAYOUTPROPAGATE
+#include "mlir/Dialect/XeGPU/Transforms/Passes.h.inc"
+} // namespace xegpu
+} // namespace mlir
+
+#define DEBUG_TYPE "xegpu-layout-propagate"
+#define DBGS() (llvm::dbgs() << "[" DEBUG_TYPE "]: ")
+
+using namespace mlir;
+using namespace mlir::dataflow;
+
+namespace {
+
+//===----------------------------------------------------------------------===//
+// Layout
+//===----------------------------------------------------------------------===//
+
+/// Helper class to store the ND layout of lanes within a subgroup and data
+/// owned by each lane.
+struct Layout {
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charithaintc wrote:

good suggestion. 
we can not it directly because `xegpu::LayoutAttr` does not implement join and meet methods. but we can explore other alternatives like keeping a `xegpu::LayoutAttr` as a data member inside `LayoutInfo`. I am not entirely sure this is possible because this would require passing an mlir context to the `LayoutInfo` class.

I think we can explore this as generalization step as we improve the analysis for the WgToSG as well. what do you think?

https://github.com/llvm/llvm-project/pull/142687