[Mlir-commits] [mlir] [mlir][scf][vector] Add `scf.parallel` vectorizer (PR #94168)

[Maksim Levental]

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@@ -0,0 +1,648 @@
+//===- SCFVectorize.cpp - SCF vectorization utilities ---------------------===//
+//
+// 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/Dialect/SCF/Transforms/SCFVectorize.h"
+
+#include "mlir/Dialect/Arith/IR/Arith.h"
+#include "mlir/Dialect/Linalg/Transforms/Transforms.h" // getCombinerOpKind
+#include "mlir/Dialect/MemRef/IR/MemRef.h"
+#include "mlir/Dialect/SCF/IR/SCF.h"
+#include "mlir/Dialect/UB/IR/UBOps.h"
+#include "mlir/Dialect/Vector/IR/VectorOps.h"
+#include "mlir/IR/IRMapping.h"
+
+using namespace mlir;
+
+static bool isSupportedVecElem(Type type) { return type.isIntOrIndexOrFloat(); }
+
+/// Return type bitwidth for vectorization purposes or 0 if type cannot be
+/// vectorized.
+static unsigned getTypeBitWidth(Type type, const DataLayout *DL) {
+  if (!isSupportedVecElem(type))
+    return 0;
+
+  if (DL)
+    return DL->getTypeSizeInBits(type);
+
+  if (type.isIntOrFloat())
+    return type.getIntOrFloatBitWidth();
+
+  return 0;
+}
+
+static unsigned getArgsTypeWidth(Operation &op, const DataLayout *DL) {
+  unsigned ret = 0;
+  for (auto arg : op.getOperands())
+    ret = std::max(ret, getTypeBitWidth(arg.getType(), DL));
+
+  for (auto res : op.getResults())
+    ret = std::max(ret, getTypeBitWidth(res.getType(), DL));
+
+  return ret;
+}
+
+static bool isSupportedVectorOp(Operation &op) {
+  return op.hasTrait<OpTrait::Vectorizable>();
+}
+
+/// Check if one `ValueRange` is permutation of another, i.e. contains same
+/// values, potentially in different order.
+static bool isRangePermutation(ValueRange val1, ValueRange val2) {
+  if (val1.size() != val2.size())
+    return false;
+
+  for (auto v1 : val1) {
+    auto it = llvm::find(val2, v1);
+    if (it == val2.end())
+      return false;
+  }
+  return true;
+}
+
+template <typename Op>
+static std::optional<unsigned>
+canTriviallyVectorizeMemOpImpl(scf::ParallelOp loop, unsigned dim, Op memOp,
+                               const DataLayout *DL) {
+  auto loopIndexVars = loop.getInductionVars();
+  assert(dim < loopIndexVars.size());
+  auto memref = memOp.getMemRef();
+  auto type = cast<MemRefType>(memref.getType());
+  auto width = getTypeBitWidth(type.getElementType(), DL);
----------------
makslevental wrote:

nit: please spell out `auto` except in cases where the spelling is very verbose (this is a general convention/rule in mlir)

https://github.com/llvm/llvm-project/pull/94168