[Mlir-commits] [mlir] [mlir] [vector] Add linearization pattern for vector.create_mask (PR #138214)

[James Newling]

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@@ -445,6 +445,64 @@ struct LinearizeVectorSplat final
   }
 };
 
+/// This pattern converts the CreateMaskOp to work on a linearized vector.
+/// It currently supports only 2D masks with a unit outer dimension.
+/// Following,
+///   vector.create_mask %arg0, %arg1 : vector<1x4xi1>
+/// is converted to:
+///   %zero = arith.constant 0 : index
+///   %cmpi = arith.cmpi sgt, %arg0, %zero : index
+///   %index = arith.index_cast %cmpi : i1 to index
+///   %mul = arith.andi %index, %arg1 : index
+///   %mask = vector.create_mask %mul : vector<4xi1>
+///   %shape_cast = vector.shape_cast %mask : vector<4xi1> to vector<1x4xi1>
+struct LinearizeVectorCreateMask final
+    : OpConversionPattern<vector::CreateMaskOp> {
+  using OpConversionPattern::OpConversionPattern;
+
+  LinearizeVectorCreateMask(const TypeConverter &typeConverter,
+                            MLIRContext *context, PatternBenefit benefit = 1)
+      : OpConversionPattern(typeConverter, context, benefit) {}
+
+  LogicalResult
+  matchAndRewrite(vector::CreateMaskOp createMaskOp, OpAdaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override {
+    Location loc = createMaskOp.getLoc();
+    VectorType srcTy = createMaskOp.getType();
+    auto srcShape = srcTy.getShape();
+    if (srcShape.size() != 2)
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newling wrote:

Consider adding 
// FIXME: add support for any vector with at most 1 non-unit dimension (like vector<1x4x1xi1>) 
here 

https://github.com/llvm/llvm-project/pull/138214