Add support for lowering mhlo.dynamic_slice to Linalg ops.

PiperOrigin-RevId: 368033540
This commit is contained in:
Hanhan Wang 2021-04-12 10:34:01 -07:00 committed by TensorFlow MLIR Team
parent 0ec0a23e61
commit a3fc99efe0
2 changed files with 94 additions and 0 deletions

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@ -1134,6 +1134,70 @@ class SliceConverter : public OpConversionPattern<OpTy> {
}
};
class DynamicSliceConverter : public OpConversionPattern<mhlo::DynamicSliceOp> {
public:
using OpConversionPattern<mhlo::DynamicSliceOp>::OpConversionPattern;
LogicalResult matchAndRewrite(
mhlo::DynamicSliceOp dynamic_slice_op, ArrayRef<Value> args,
ConversionPatternRewriter& rewriter) const final {
auto loc = dynamic_slice_op.getLoc();
mhlo::DynamicSliceOp::Adaptor adaptor(args);
auto arg_type = adaptor.operand().getType().dyn_cast<ShapedType>();
if (!arg_type || !arg_type.hasRank()) {
return rewriter.notifyMatchFailure(dynamic_slice_op,
"require known-rank args");
}
auto index_type = rewriter.getIndexType();
SmallVector<OpFoldResult, 3> start_indices, sizes;
Value zero = rewriter.create<ConstantOp>(
loc, rewriter.getZeroAttr(adaptor.start_indices()[0]
.getType()
.cast<RankedTensorType>()
.getElementType()));
for (auto en : llvm::enumerate(
llvm::zip(adaptor.start_indices(),
dynamic_slice_op.slice_sizes().getValues<int64_t>()))) {
int64_t size = std::get<1>(en.value());
sizes.push_back(rewriter.getI64IntegerAttr(size));
// By mhlo.DynamicSlice definition:
// `start_indices[i] = clamp(start_indices[i],
// 0, operand.dimension_size[i] - size_indices[i])`
Value start_index =
rewriter.create<tensor::ExtractOp>(loc, std::get<0>(en.value()));
Value ub = rewriter.createOrFold<memref::DimOp>(loc, adaptor.operand(),
en.index());
// ClampOp lowering does not support index type, so cast it into integer
// type.
ub = rewriter.createOrFold<IndexCastOp>(loc, start_index.getType(), ub);
ub = rewriter.createOrFold<SubIOp>(
loc, ub,
rewriter.create<ConstantOp>(
loc, rewriter.getIntegerAttr(start_index.getType(), size)));
// TODO(hanchung): This is a workaround to use the method because only
// lmhlo version is defined. The implementation in
// map_lmhlo_to_scalar_op.h requires to pass a mhlo op. It will convert it
// to an lmhlo op and call the lmhlo implementation.
start_index = lmhlo::HloOpToStdScalarOp::map<lmhlo::ClampOp>(
loc, start_index.getType(), ArrayRef<Value>{zero, start_index, ub},
&rewriter);
start_indices.push_back(
rewriter.create<IndexCastOp>(loc, index_type, start_index)
.getResult());
}
int64_t rank = arg_type.getRank();
SmallVector<OpFoldResult, 3> strides(rank, rewriter.getI64IntegerAttr(1));
rewriter.replaceOpWithNewOp<SubTensorOp>(
dynamic_slice_op, dynamic_slice_op.getType().cast<RankedTensorType>(),
adaptor.operand(), start_indices, sizes, strides);
return success();
}
};
enum class DotOperationType {
kVectorDot = 0,
kMatrixVector = 1,
@ -2090,6 +2154,7 @@ void populateHLOToLinalgConversionPattern(MLIRContext* context,
ReshapeOpConverter<mhlo::ReshapeOp, false>,
ReverseConverter<mhlo::ReverseOp, false>,
SliceConverter<mhlo::SliceOp, false>,
DynamicSliceConverter,
TransposeConverter<mhlo::TransposeOp, false>,
DotOpOnTensorsConversion<DotOperationType::kMatrixMatrix,
linalg::MatmulOp>,

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@ -1532,6 +1532,35 @@ func @slice_stride_part(%arg0: tensor<3x4xi32>) -> tensor<1x2xi32> {
// -----
func @dynamic_slice(%arg: tensor<3x4xf32>, %start1: tensor<i64>, %start2: tensor<i64>) -> tensor<1x4xf32> {
%0 = "mhlo.dynamic-slice"(%arg, %start1, %start2) {
slice_sizes = dense<[1, 4]> : tensor<2xi64>
} : (tensor<3x4xf32>, tensor<i64>, tensor<i64>) -> tensor<1x4xf32>
return %0 : tensor<1x4xf32>
}
// CHECK-LABEL: func @dynamic_slice
// CHECK-SAME: %[[ARG0:[a-zA-Z0-9_]*]]
// CHECK-SAME: %[[ARG1:[a-zA-Z0-9_]*]]
// CHECK-SAME: %[[ARG2:[a-zA-Z0-9_]*]]
// CHECK: %[[C0:.*]] = constant 0 : i64
// CHECK: %[[SCALAR1:.*]] = tensor.extract %[[ARG1]][] : tensor<i64>
// CHECK: %[[UB1:.*]] = constant 2 : i64
// CHECK: %[[COND1:.*]] = cmpi slt, %[[SCALAR1]], %[[UB1]] : i64
// CHECK: %[[T1:.*]] = select %[[COND1]], %[[SCALAR1]], %[[UB1]] : i64
// CHECK: %[[COND2:.*]] = cmpi sgt, %[[T1]], %[[C0]] : i64
// CHECK: %[[CLAMPED1:.*]] = select %[[COND2]], %[[T1]], %[[C0]] : i64
// CHECK: %[[START1:.*]] = index_cast %[[CLAMPED1]] : i64 to index
// CHECK: %[[SCALAR2:.*]] = tensor.extract %[[ARG2]][] : tensor<i64>
// CHECK: %[[UB2:.*]] = constant 0 : i64
// CHECK: %[[COND3:.*]] = cmpi slt, %[[SCALAR2]], %[[UB2]] : i64
// CHECK: %[[T2:.*]] = select %[[COND3]], %[[SCALAR2]], %[[UB2]] : i64
// CHECK: %[[COND4:.*]] = cmpi sgt, %[[T2]], %[[C0]] : i64
// CHECK: %[[CLAMPED2:.*]] = select %[[COND4]], %[[T2]], %[[C0]] : i64
// CHECK: %[[START2:.*]] = index_cast %[[CLAMPED2]] : i64 to index
// CHECK: subtensor %[[ARG0]][%[[START1]], %[[START2]]] [1, 4] [1, 1]
// -----
func @pad_cst(%arg0: tensor<12x4xf32>) -> tensor<18x12xf32> {
%0 = constant dense<0.0> : tensor<f32>
%1 = "mhlo.pad"(%arg0, %0) {