[MLIR][Vector] Implement transferXXPermutationLowering as MaskableOpRewritePattern (#91987)

* Implements `TransferWritePermutationLowering`,
`TransferReadPermutationLowering` and
`TransferWriteNonPermutationLowering` as a MaskableOpRewritePattern.
Allowing to exit gracefully when such use of a xferOp is inside a
`vector::MaskOp`
* Updates MaskableOpRewritePattern to handle MemRefs and buffer
semantics providing empty `Value()` as a return value for
`matchAndRewriteMaskableOp` now represents successful rewriting without
value to replace the original op.

Split of #90835

Author: nujaa

mlir/include/mlir/Dialect/Vector/Utils/VectorUtils.h

@@ -157,7 +157,14 @@ struct MaskableOpRewritePattern : OpRewritePattern<SourceOp> {
     if (failed(newOp))
       return failure();
 
-    rewriter.replaceOp(rootOp, *newOp);
+    // Rewriting succeeded but there are no values to replace.
+    if (rootOp->getNumResults() == 0) {
+      rewriter.eraseOp(rootOp);
+    } else {
+      assert(*newOp != Value() &&
+             "Cannot replace an op's use with an empty value.");
+      rewriter.replaceOp(rootOp, *newOp);
+    }
     return success();
   }
 

mlir/lib/Dialect/Vector/Transforms/LowerVectorTransfer.cpp

@@ -90,14 +90,19 @@ namespace {
 /// Note that an alternative is to transform it to linalg.transpose +
 /// vector.transfer_read to do the transpose in memory instead.
 struct TransferReadPermutationLowering
-    : public OpRewritePattern<vector::TransferReadOp> {
-  using OpRewritePattern::OpRewritePattern;
+    : public MaskableOpRewritePattern<vector::TransferReadOp> {
+  using MaskableOpRewritePattern::MaskableOpRewritePattern;
 
-  LogicalResult matchAndRewrite(vector::TransferReadOp op,
-                                PatternRewriter &rewriter) const override {
+  FailureOr<mlir::Value>
+  matchAndRewriteMaskableOp(vector::TransferReadOp op,
+                            MaskingOpInterface maskOp,
+                            PatternRewriter &rewriter) const override {
     // TODO: support 0-d corner case.
     if (op.getTransferRank() == 0)
       return rewriter.notifyMatchFailure(op, "0-d corner case not supported");
+    // TODO: Support transfer_read inside MaskOp case.
+    if (maskOp)
+      return rewriter.notifyMatchFailure(op, "Masked case not supported");
 
     SmallVector<unsigned> permutation;
     AffineMap map = op.getPermutationMap();
@@ -142,9 +147,9 @@ struct TransferReadPermutationLowering
 
     // Transpose result of transfer_read.
     SmallVector<int64_t> transposePerm(permutation.begin(), permutation.end());
-    rewriter.replaceOpWithNewOp<vector::TransposeOp>(op, newRead,
-                                                     transposePerm);
-    return success();
+    return rewriter
+        .create<vector::TransposeOp>(op.getLoc(), newRead, transposePerm)
+        .getResult();
   }
 };
 
@@ -165,14 +170,19 @@ struct TransferReadPermutationLowering
 ///     %v = vector.transfer_write %tmp ...
 ///         permutation_map: (d0, d1, d2, d3) -> (d2, d3)
 struct TransferWritePermutationLowering
-    : public OpRewritePattern<vector::TransferWriteOp> {
-  using OpRewritePattern::OpRewritePattern;
+    : public MaskableOpRewritePattern<vector::TransferWriteOp> {
+  using MaskableOpRewritePattern::MaskableOpRewritePattern;
 
-  LogicalResult matchAndRewrite(vector::TransferWriteOp op,
-                                PatternRewriter &rewriter) const override {
+  FailureOr<mlir::Value>
+  matchAndRewriteMaskableOp(vector::TransferWriteOp op,
+                            MaskingOpInterface maskOp,
+                            PatternRewriter &rewriter) const override {
     // TODO: support 0-d corner case.
     if (op.getTransferRank() == 0)
       return rewriter.notifyMatchFailure(op, "0-d corner case not supported");
+    // TODO: Support transfer_write inside MaskOp case.
+    if (maskOp)
+      return rewriter.notifyMatchFailure(op, "Masked case not supported");
 
     SmallVector<unsigned> permutation;
     AffineMap map = op.getPermutationMap();
@@ -207,11 +217,14 @@ struct TransferWritePermutationLowering
         op.getLoc(), op.getVector(), indices);
     auto newMap = AffineMap::getMinorIdentityMap(
         map.getNumDims(), map.getNumResults(), rewriter.getContext());
-    rewriter.replaceOpWithNewOp<vector::TransferWriteOp>(
-        op, newVec, op.getSource(), op.getIndices(), AffineMapAttr::get(newMap),
-        op.getMask(), newInBoundsAttr);
-
-    return success();
+    auto newWrite = rewriter.create<vector::TransferWriteOp>(
+        op.getLoc(), newVec, op.getSource(), op.getIndices(),
+        AffineMapAttr::get(newMap), op.getMask(), newInBoundsAttr);
+    if (newWrite.hasPureTensorSemantics())
+      return newWrite.getResult();
+    // In the memref case there's no return value. Use empty value to signal
+    // success.
+    return Value();
   }
 };
 
@@ -231,14 +244,19 @@ struct TransferWritePermutationLowering
 ///     vector<1x8x16xf32>
 /// ```
 struct TransferWriteNonPermutationLowering
-    : public OpRewritePattern<vector::TransferWriteOp> {
-  using OpRewritePattern::OpRewritePattern;
+    : public MaskableOpRewritePattern<vector::TransferWriteOp> {
+  using MaskableOpRewritePattern::MaskableOpRewritePattern;
 
-  LogicalResult matchAndRewrite(vector::TransferWriteOp op,
-                                PatternRewriter &rewriter) const override {
+  FailureOr<mlir::Value>
+  matchAndRewriteMaskableOp(vector::TransferWriteOp op,
+                            MaskingOpInterface maskOp,
+                            PatternRewriter &rewriter) const override {
     // TODO: support 0-d corner case.
     if (op.getTransferRank() == 0)
       return rewriter.notifyMatchFailure(op, "0-d corner case not supported");
+    // TODO: Support transfer_write inside MaskOp case.
+    if (maskOp)
+      return rewriter.notifyMatchFailure(op, "Masked case not supported");
 
     SmallVector<unsigned> permutation;
     AffineMap map = op.getPermutationMap();
@@ -285,10 +303,14 @@ struct TransferWriteNonPermutationLowering
       newInBoundsValues.push_back(op.isDimInBounds(i));
     }
     ArrayAttr newInBoundsAttr = rewriter.getBoolArrayAttr(newInBoundsValues);
-    rewriter.replaceOpWithNewOp<vector::TransferWriteOp>(
-        op, newVec, op.getSource(), op.getIndices(), AffineMapAttr::get(newMap),
-        newMask, newInBoundsAttr);
-    return success();
+    auto newWrite = rewriter.create<vector::TransferWriteOp>(
+        op.getLoc(), newVec, op.getSource(), op.getIndices(),
+        AffineMapAttr::get(newMap), newMask, newInBoundsAttr);
+    if (newWrite.hasPureTensorSemantics())
+      return newWrite.getResult();
+    // In the memref case there's no return value. Use empty value to signal
+    // success.
+    return Value();
   }
 };
 

mlir/test/Dialect/Vector/vector-transfer-permutation-lowering.mlir

@@ -46,6 +46,51 @@ func.func @permutation_with_mask_xfer_write_scalable(%arg0: vector<4x[8]xi16>, %
     return
 }
 
+// transfer_write in MaskOp case not supported.
+// CHECK-LABEL: func @masked_permutation_xfer_write_fixed_width
+//  CHECK-SAME:        %[[ARG_0:.*]]: tensor<?x?xf32>,
+//  CHECK-SAME:        %[[ARG_1:.*]]: vector<16xf32>,
+//  CHECK-SAME:        %[[IDX:.*]]: index,
+//  CHECK-SAME:        %[[MASK:.*]]: vector<16xi1>
+//   CHECK-NOT:   vector.transpose
+//       CHECK:   %[[RES:.*]] = vector.mask %[[MASK]] { vector.transfer_write %[[ARG_1]], %[[ARG_0]]{{.*}} vector<16xf32>, tensor<?x?xf32> } : vector<16xi1> -> tensor<?x?xf32>
+func.func @masked_permutation_xfer_write_fixed_width(%t: tensor<?x?xf32>, %val: vector<16xf32>, %idx: index, %mask: vector<16xi1>) -> tensor<?x?xf32> {
+  %r = vector.mask %mask { vector.transfer_write %val, %t[%idx, %idx] {permutation_map = affine_map<(d0, d1) -> (d0)>} : vector<16xf32>, tensor<?x?xf32> } : vector<16xi1> -> tensor<?x?xf32>
+  return %r : tensor<?x?xf32>
+}
+
+// CHECK-LABEL: func.func @masked_permutation_xfer_write_scalable(
+//  CHECK-SAME:        %[[ARG_0:.*]]: vector<4x[8]xi16>,
+//  CHECK-SAME:        %[[ARG_1:.*]]: tensor<?x?x?x?xf32>,
+//  CHECK-SAME:        %[[MASK:.*]]: vector<4x[8]xi1>)
+//  CHECK-SAME:        -> tensor<?x?x?x?xf32> {
+//   CHECK-NOT:   vector.transpose
+//       CHECK:   %[[R:.*]] = vector.mask %[[MASK]] { vector.transfer_write %[[ARG_0]], %[[ARG_1]]{{.*}} : vector<4x[8]xi16>, tensor<?x?x?x?xf32> } : vector<4x[8]xi1> -> tensor<?x?x?x?xf32>
+func.func @masked_permutation_xfer_write_scalable(%arg0: vector<4x[8]xi16>, %t: tensor<?x?x?x?xf32>, %mask:  vector<4x[8]xi1>) -> tensor<?x?x?x?xf32> {
+     %c0 = arith.constant 0 : index
+     %r = vector.mask %mask { vector.transfer_write %arg0, %t[%c0, %c0, %c0, %c0] {in_bounds = [true, true], permutation_map = affine_map<(d0, d1, d2, d3) -> (d1, d2)>
+} : vector<4x[8]xi16>, tensor<?x?x?x?xf32> } : vector<4x[8]xi1> -> tensor<?x?x?x?xf32>
+
+    return %r : tensor<?x?x?x?xf32>
+}
+
+// transfer_write in MaskOp case not supported.
+// CHECK-LABEL: func @masked_non_permutation_xfer_write_fixed_width
+//  CHECK-SAME:      %[[ARG0:.*]]: tensor<?x?x?x?xf32>
+//  CHECK-SAME:      %[[ARG1:.*]]: vector<14x8x16xf32>
+//  CHECK-SAME:      %[[IDX:.*]]: index) -> tensor<?x?x?x?xf32>
+//   CHECK-NOT:   vector.broadcast
+//       CHECK:   %[[masked1:.*]] = vector.mask %0 { vector.transfer_write %[[ARG1]], %[[ARG0]]{{.*}} : vector<14x8x16xf32>, tensor<?x?x?x?xf32> } : vector<14x8x16xi1> -> tensor<?x?x?x?xf32>
+func.func @masked_non_permutation_xfer_write_fixed_width(
+    %arg0 : tensor<?x?x?x?xf32>,
+    %v1 : vector<14x8x16xf32>, %dim : index) -> tensor<?x?x?x?xf32> {
+  %c0 = arith.constant 0 : index
+  %mask = vector.create_mask %dim, %dim, %dim : vector<14x8x16xi1>
+  %0 = vector.mask %mask { vector.transfer_write %v1, %arg0[%c0, %c0, %c0, %c0] {in_bounds = [false, false, true], permutation_map = affine_map<(d0, d1, d2, d3) -> (d0, d1, d3)>} : vector<14x8x16xf32>, tensor<?x?x?x?xf32> } : vector<14x8x16xi1> -> tensor<?x?x?x?xf32>
+
+  return %0 : tensor<?x?x?x?xf32>
+}
+
 ///----------------------------------------------------------------------------------------
 /// vector.transfer_read
 ///----------------------------------------------------------------------------------------
@@ -101,6 +146,37 @@ func.func @permutation_with_mask_xfer_read_scalable(%mem: memref<?x?xf32>, %dim_
   return %1 : vector<8x[4]x2xf32>
 }
 
+// transfer_read in MaskOp case not supported.
+// CHECK-LABEL: func @masked_permutation_xfer_read_fixed_width
+//  CHECK-SAME:        %[[ARG_0:.*]]: tensor<?x1xf32>,
+//  CHECK-SAME:        %[[ARG_1:.*]]: vector<4x1xi1>
+//   CHECK-NOT:   vector.transpose
+//       CHECK:   vector.mask %[[ARG_1]] { vector.transfer_read %[[ARG_0]]{{.*}}: tensor<?x1xf32>, vector<1x4x4xf32> } : vector<4x1xi1> -> vector<1x4x4xf32>
+func.func @masked_permutation_xfer_read_fixed_width(%arg0: tensor<?x1xf32>, %mask : vector<4x1xi1>) {
+  %cst = arith.constant 0.000000e+00 : f32
+  %c0 = arith.constant 0 : index
+  %3 = vector.mask %mask { vector.transfer_read %arg0[%c0, %c0], %cst {permutation_map = affine_map<(d0, d1) -> (d1, 0, d0)>} : tensor<?x1xf32>, vector<1x4x4xf32> } : vector<4x1xi1> -> vector<1x4x4xf32>
+  call @test.some_use(%3) : (vector<1x4x4xf32>) -> ()
+  return
+}
+func.func private @test.some_use(vector<1x4x4xf32>)
+
+// CHECK-LABEL:  func.func @masked_permutation_xfer_read_scalable(
+//  CHECK-SAME:      %[[ARG_0:.*]]: tensor<?x?xf32>,
+//  CHECK-SAME:      %[[MASK:.*]]: vector<2x[4]xi1>) -> vector<8x[4]x2xf32> {
+//   CHECK-NOT:    vector.transpose
+//       CHECK:    %[[T_READ:.*]] = vector.mask %[[MASK]] { vector.transfer_read %[[ARG_0]]{{.*}} : tensor<?x?xf32>, vector<8x[4]x2xf32> } : vector<2x[4]xi1> -> vector<8x[4]x2xf32>
+func.func @masked_permutation_xfer_read_scalable(%t: tensor<?x?xf32>, %mask : vector<2x[4]xi1>) -> vector<8x[4]x2xf32> {
+
+  %c0 = arith.constant 0 : index
+  %cst_0 = arith.constant 0.000000e+00 : f32
+
+  %1 = vector.mask %mask { vector.transfer_read %t[%c0, %c0], %cst_0
+    {in_bounds = [true, true, true], permutation_map = affine_map<(d0, d1) -> (0, d1, d0)>}
+    : tensor<?x?xf32>, vector<8x[4]x2xf32> } :vector<2x[4]xi1> -> vector<8x[4]x2xf32>
+  return %1 : vector<8x[4]x2xf32>
+}
+
 module attributes {transform.with_named_sequence} {
   transform.named_sequence @__transform_main(%module_op: !transform.any_op {transform.readonly}) {
     %f = transform.structured.match ops{["func.func"]} in %module_op