[Mlir-commits] [mlir] [mlir][ArmSVE] Add `-arm-sve-legalize-vector-storage` pass (PR #68794)

[Andrzej Warzyński]

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@@ -0,0 +1,327 @@
+//===- LegalizeVectorStorage.cpp - Ensures SVE loads/stores are legal -----===//
+//
+// 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/ArmSVE/IR/ArmSVEDialect.h"
+#include "mlir/Dialect/ArmSVE/Transforms/Passes.h"
+#include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/MemRef/IR/MemRef.h"
+#include "mlir/Dialect/Vector/IR/VectorOps.h"
+#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
+
+namespace mlir::arm_sve {
+#define GEN_PASS_DEF_LEGALIZEVECTORSTORAGE
+#include "mlir/Dialect/ArmSVE/Transforms/Passes.h.inc"
+} // namespace mlir::arm_sve
+
+using namespace mlir;
+using namespace mlir::arm_sve;
+
+// A tag to mark unrealized_conversions produced by this pass. This is used to
+// detect IR this pass failed to completely legalize, and report an error.
+// If everything was successfully legalized, no tagged ops will remain after
+// this pass.
+constexpr StringLiteral kSVELegalizerTag("__arm_sve_legalize_vector_storage__");
+
+namespace {
+
+/// A (legal) SVE predicate mask that has a logical size, i.e. the number of
+/// bits match the number of lanes it masks (such as vector<[4]xi1>), but is too
+/// small to be stored to memory.
+bool isLogicalSVEMaskType(VectorType type) {
+  return type.getRank() > 0 && type.getElementType().isInteger(1) &&
+         type.getScalableDims().back() && type.getShape().back() < 16 &&
+         llvm::isPowerOf2_32(type.getShape().back()) &&
+         !llvm::is_contained(type.getScalableDims().drop_back(), true);
+}
+
+VectorType widenScalableMaskTypeToSvbool(VectorType type) {
+  assert(isLogicalSVEMaskType(type));
+  return VectorType::Builder(type).setDim(type.getRank() - 1, 16);
+}
+
+template <typename TOp, typename TLegalizerCallback>
+void replaceOpWithLegalizedOp(PatternRewriter &rewriter, TOp op,
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banach-space wrote:

static?

Also, could you add a short comment that would explain the rationale for having this? I guess that it's mostly a syntactic sugar? (i.e. a helper method)

https://github.com/llvm/llvm-project/pull/68794