[Mlir-commits] [mlir] [mlir][linalg] Morphism across linalg named, category and generic ops. (PR #148424)

[Javed Absar]

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@@ -0,0 +1,97 @@
+//===- NamedToElementwise.cpp - convert linalg named op into elementwise --===//
+//
+// 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 rewriting those linalg named ops that are essentially
+// elementwise e.g. `linalg.exp`, to `linalg.elementwise`. This allows further
+// optimization on `linalg.elementwise` such as folding transpose, broadcast.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Dialect/Linalg/IR/Linalg.h"
+#include "mlir/Dialect/Linalg/Passes.h"
+#include "mlir/Dialect/Linalg/Transforms/Transforms.h"
+#include "mlir/IR/PatternMatch.h"
+#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/TypeSwitch.h"
+
+using namespace mlir;
+using namespace mlir::linalg;
+
+#define DEBUG_TYPE "linalg-named-to-elementwise"
+
+namespace {
+ElementwiseKind getKind(Operation *op) {
+  return llvm::TypeSwitch<Operation *, ElementwiseKind>(op)
+      .Case([](SelectOp) { return ElementwiseKind::select; })
+      .Case([](AddOp) { return ElementwiseKind::add; })
+      .Case([](SubOp) { return ElementwiseKind::sub; })
+      .Case([](MulOp) { return ElementwiseKind::mul; })
+      .Case([](DivOp) { return ElementwiseKind::div; })
+      .Case([](DivUnsignedOp) { return ElementwiseKind::div_unsigned; })
+      .Case([](PowFOp) { return ElementwiseKind::powf; })
+      .Case([](ExpOp) { return ElementwiseKind::exp; })
+      .Case([](LogOp) { return ElementwiseKind::log; })
+      .Case([](AbsOp) { return ElementwiseKind::abs; })
+      .Case([](CeilOp) { return ElementwiseKind::ceil; })
+      .Case([](FloorOp) { return ElementwiseKind::floor; })
+      .Case([](NegFOp) { return ElementwiseKind::negf; })
+      .Case([](ReciprocalOp) { return ElementwiseKind::reciprocal; })
+      .Case([](RoundOp) { return ElementwiseKind::round; })
+      .Case([](SqrtOp) { return ElementwiseKind::sqrt; })
+      .Case([](RsqrtOp) { return ElementwiseKind::rsqrt; })
+      .Case([](SquareOp) { return ElementwiseKind::square; })
+      .Case([](TanhOp) { return ElementwiseKind::tanh; })
+      .Case([](ErfOp) { return ElementwiseKind::erf; })
+      .Default([&](Operation *op) {
+        llvm_unreachable("unhandled case in named to elementwise");
+        return ElementwiseKind::sub;
+      });
+}
+
+template <typename NamedOpTy>
+struct NamedToElementwisePattern : public OpRewritePattern<NamedOpTy> {
+  using OpRewritePattern<NamedOpTy>::OpRewritePattern;
+
+  LogicalResult matchAndRewrite(NamedOpTy op,
+                                PatternRewriter &rewriter) const override {
+    SmallVector<NamedAttribute> attrs;
+    auto kindAttr = ElementwiseKindAttr::get(op.getContext(), getKind(op));
+    attrs.push_back(rewriter.getNamedAttr("kind", kindAttr));
+    attrs.push_back(
----------------
javedabsar1 wrote:

Yes it is picking the indexing map from op, but we need to provide it to the elementwise constructor. We could
let the constructor check if 'indexing_maps' attr is present, and if not select from 
`ElementwiseOp::getDefaultIndexingMaps(unsigned numMaps, unsigned numDims, MLIRContext *context)`. But that seems more round-about to me.
 

https://github.com/llvm/llvm-project/pull/148424