[Mlir-commits] [mlir] [mlir][ArmSME] Add initial SME vector legalization pass (PR #79152)

[Andrzej Warzyński]

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@@ -0,0 +1,308 @@
+#include "mlir/Dialect/ArmSME/IR/ArmSME.h"
+#include "mlir/Dialect/ArmSME/Transforms/Passes.h"
+#include "mlir/Dialect/ArmSME/Utils/Utils.h"
+#include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/Func/Transforms/OneToNFuncConversions.h"
+#include "mlir/Dialect/SCF/Transforms/Patterns.h"
+#include "mlir/Dialect/Utils/IndexingUtils.h"
+#include "mlir/Transforms/OneToNTypeConversion.h"
+
+#define DEBUG_TYPE "arm-sme-vector-legalization"
+
+namespace mlir::arm_sme {
+#define GEN_PASS_DEF_VECTORLEGALIZATION
+#include "mlir/Dialect/ArmSME/Transforms/Passes.h.inc"
+} // namespace mlir::arm_sme
+
+using namespace mlir;
+using namespace mlir::arm_sme;
+
+namespace {
+
+struct SMETile {
+  // Note: The units of (row, col) are vscale (as SME tiles are scalable).
+  int row{0};
+  int col{0};
+  VectorType type;
+};
+
+/// Adds a constant scalable offset to `indices`. i.e. for 2D:
+/// { indices[0] + offset[0] * vscale, indices[1] + offset[1] * vscale }
+SmallVector<Value, 2> addConstantScalableOffset(OpBuilder &builder,
+                                                Location loc,
+                                                ValueRange indices,
+                                                ArrayRef<int> scalableOffset) {
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banach-space wrote:

Is this an elementwise operation? As in, for every "index" in `indices` there's an "offset" in `scalableOffset` and the result is "index" + "offset"? If yes then this will basically be adding 2 vectors and:
* `indices` implies that there are multiple elements in this vector,
* `scalableOffset` implies that there's only one element.

https://github.com/llvm/llvm-project/pull/79152