feat(ir): Accept pad_value kwarg on tile.slice

python/pypto/ir/op/tile_ops.py

@@ -1919,6 +1919,7 @@ def slice(
     shape: Sequence[int | Expr] | _ir_core.MakeTuple,
     offset: Sequence[int | Expr] | _ir_core.MakeTuple,
     valid_shape: Sequence[int | Expr] | _ir_core.MakeTuple | None = None,
+    pad_value: PadValue | None = None,
     span: Span | None = None,
 ) -> Call:
     """Create a slice of a tile with static shape and optional valid shape.
@@ -1929,6 +1930,9 @@ def slice(
         offset: Offset dimensions for the slice, or a MakeTuple
         valid_shape: Valid shape dimensions, or a MakeTuple. When omitted, shape
             is reused as the valid shape.
+        pad_value: Optional padding mode for out-of-valid-shape elements
+            (PadValue.zero, PadValue.max, or PadValue.min). When omitted, no
+            padding is applied (equivalent to PadValue.null).
         span: Optional source span for debugging (auto-captured if not provided)
 
     Returns:
@@ -1951,7 +1955,11 @@ def slice(
             )
         args.append(valid_shape_tuple)
 
-    return _ir_core.create_op_call("tile.slice", args, {}, actual_span)
+    kwargs: dict[str, Any] = {}
+    if pad_value is not None:
+        kwargs["pad_value"] = pad_value
+
+    return _ir_core.create_op_call("tile.slice", args, kwargs, actual_span)
 
 
 def reshape(

python/pypto/language/op/tile_ops.py

@@ -15,6 +15,7 @@
 Accessed as ``pl.tile.*``
 """
 
+import warnings
 from collections.abc import Sequence
 from typing import overload
 
@@ -1214,6 +1215,7 @@ def slice(
     shape: Sequence[IntLike],
     offset: Sequence[IntLike],
     valid_shape: Sequence[IntLike] | None = None,
+    pad_value: PadValue | None = None,
 ) -> Tile:
     """Create a slice of a tile with static shape and optional valid shape.
 
@@ -1223,17 +1225,31 @@ def slice(
         offset: Offset dimensions for the slice
         valid_shape: Valid shape dimensions. When omitted, shape is reused as the
             logical valid shape.
+        pad_value: Optional padding mode (PadValue.zero, PadValue.max, or
+            PadValue.min) applied to out-of-valid-shape elements. Only
+            meaningful when ``valid_shape`` is smaller than ``shape``.
 
     Returns:
         Tile wrapping the slice operation
     """
+    if pad_value is not None and pad_value != PadValue.null and valid_shape is None:
+        warnings.warn(
+            f"tile.slice received pad_value={pad_value!r} but no valid_shape. "
+            f"pad_value has no effect unless valid_shape is smaller than shape. "
+            f"If you intend to narrow the valid region later via "
+            f"tile.set_validshape, you can ignore this warning; otherwise "
+            f"pass valid_shape=... to tile.slice.",
+            stacklevel=2,
+        )
+
     tile_expr = tile.unwrap()
     normalized_valid_shape = None if valid_shape is None else _normalize_intlike(valid_shape)
     call_expr = _ir_ops.slice(
         tile_expr,
         _normalize_intlike(shape),
         _normalize_intlike(offset),
         normalized_valid_shape,
+        pad_value=pad_value,
     )
     return Tile(expr=call_expr)
 

src/ir/op/tile_ops/transform.cpp

@@ -188,6 +188,20 @@ TypePtr DeduceTileSliceType(const std::vector<ExprPtr>& args,
 
   tile_view.blayout = InferTileLayoutFromShape(new_shape);
 
+  // Read optional pad_value kwarg (default PadValue::null = no padding).
+  PadValue pad_value = PadValue::null;
+  for (const auto& [k, v] : kwargs) {
+    if (k != "pad_value") continue;
+    CHECK(v.type() == typeid(PadValue))
+        << "tile.slice pad_value must be a PadValue enum, got " << v.type().name();
+    pad_value = std::any_cast<PadValue>(v);
+    CHECK(pad_value == PadValue::null || pad_value == PadValue::zero || pad_value == PadValue::max ||
+          pad_value == PadValue::min)
+        << "tile.slice pad_value has invalid enum value: " << static_cast<int>(pad_value);
+    break;
+  }
+  tile_view.pad = pad_value;
+
   return std::make_shared<TileType>(new_shape, tile_type->dtype_, std::nullopt, tile_view);
 }
 
@@ -298,6 +312,7 @@ REGISTER_OP("tile.slice")
     .add_argument("offset", "Offset dimensions (TupleType of ScalarType(INT64/UINT64/INDEX))")
     .add_argument("valid_shape", "Optional logical valid shape (TupleType of ScalarType(INT64/UINT64/INDEX))")
     .set_output_memory_inherit_input()
+    .set_attr<PadValue>("pad_value")
     .f_deduce_type([](const std::vector<ExprPtr>& args,
                       const std::vector<std::pair<std::string, std::any>>& kwargs) {
       return DeduceTileSliceType(args, kwargs);

tests/ut/ir/operators/test_op_registry.py

@@ -485,6 +485,12 @@ def test_fillpad_kwarg_schema():
     assert tile_fillpad_inplace_op.has_attr("pad_value")
 
 
+def test_tile_slice_pad_value_kwarg_schema():
+    """Test that tile.slice declares pad_value in its kwarg schema."""
+    tile_slice_op = ir.get_op("tile.slice")
+    assert tile_slice_op.has_attr("pad_value")
+
+
 class TestOpMemorySpecRegistry:
     """Test that op memory specs are correctly registered and queryable."""
 

tests/ut/ir/operators/test_tile_ops.py

@@ -1017,6 +1017,95 @@ def test_tile_slice_rejects_dynamic_shape(self):
         with pytest.raises(ValueError, match="compile-time constant"):
             tile.slice(tile_var, [8, valid_n], [0, 0])
 
+    @staticmethod
+    def _make_slice_tile_var():
+        """Build a [16, 32] FP16 tile Var for slice pad_value tests."""
+        span = ir.Span.unknown()
+        dim16 = ir.ConstInt(16, DataType.INT32, span)
+        dim32 = ir.ConstInt(32, DataType.INT32, span)
+        tile_type = ir.TileType([dim16, dim32], DataType.FP16)
+        return ir.Var("tile", tile_type, span)
+
+    def test_tile_slice_with_pad_value_zero(self):
+        """tile.slice writes pad_value=zero to the output tile_view.pad."""
+        tile_var = self._make_slice_tile_var()
+        call = tile.slice(tile_var, [8, 16], [0, 0], valid_shape=[8, 4], pad_value=ir.PadValue.zero)
+
+        assert isinstance(call, ir.Call)
+        assert call.op.name == "tile.slice"
+        result_type = call.type
+        assert isinstance(result_type, ir.TileType)
+        assert result_type.tile_view is not None
+        assert result_type.tile_view.pad == ir.PadValue.zero
+        assert len(result_type.tile_view.valid_shape) == 2
+        assert isinstance(result_type.tile_view.valid_shape[0], ir.ConstInt)
+        assert result_type.tile_view.valid_shape[0].value == 8
+        assert isinstance(result_type.tile_view.valid_shape[1], ir.ConstInt)
+        assert result_type.tile_view.valid_shape[1].value == 4
+
+    def test_tile_slice_with_pad_value_min(self):
+        """tile.slice writes pad_value=min to the output tile_view.pad."""
+        tile_var = self._make_slice_tile_var()
+        call = tile.slice(tile_var, [8, 16], [0, 0], valid_shape=[8, 4], pad_value=ir.PadValue.min)
+
+        result_type = call.type
+        assert isinstance(result_type, ir.TileType)
+        assert result_type.tile_view is not None
+        assert result_type.tile_view.pad == ir.PadValue.min
+
+    def test_tile_slice_with_pad_value_max(self):
+        """tile.slice writes pad_value=max to the output tile_view.pad."""
+        tile_var = self._make_slice_tile_var()
+        call = tile.slice(tile_var, [8, 16], [0, 0], valid_shape=[8, 4], pad_value=ir.PadValue.max)
+
+        result_type = call.type
+        assert isinstance(result_type, ir.TileType)
+        assert result_type.tile_view is not None
+        assert result_type.tile_view.pad == ir.PadValue.max
+
+    def test_tile_slice_default_pad_is_null(self):
+        """tile.slice without pad_value defaults to PadValue.null (backward compat)."""
+        tile_var = self._make_slice_tile_var()
+        call = tile.slice(tile_var, [8, 16], [0, 0])
+
+        result_type = call.type
+        assert isinstance(result_type, ir.TileType)
+        assert result_type.tile_view is not None
+        assert result_type.tile_view.pad == ir.PadValue.null
+
+    def test_tile_slice_rejects_bad_pad_value(self):
+        """tile.slice rejects a non-PadValue pad_value kwarg via registry validation."""
+        tile_var = self._make_slice_tile_var()
+        span = tile_var.span
+        shape_tuple = ir.MakeTuple(
+            [ir.ConstInt(8, DataType.INT32, span), ir.ConstInt(16, DataType.INT32, span)], span
+        )
+        offset_tuple = ir.MakeTuple(
+            [ir.ConstInt(0, DataType.INT32, span), ir.ConstInt(0, DataType.INT32, span)], span
+        )
+        valid_shape_tuple = ir.MakeTuple(
+            [ir.ConstInt(8, DataType.INT32, span), ir.ConstInt(4, DataType.INT32, span)], span
+        )
+        with pytest.raises(TypeError, match="'pad_value'.*incompatible type"):
+            ir.create_op_call(
+                "tile.slice",
+                [tile_var, shape_tuple, offset_tuple, valid_shape_tuple],
+                {"pad_value": 5},
+                span,
+            )
+
+    def test_tile_slice_pad_without_valid_shape_warns(self):
+        """DSL emits a UserWarning when pad_value is set but valid_shape is None."""
+        span = ir.Span.unknown()
+        dim16 = ir.ConstInt(16, DataType.INT32, span)
+        dim32 = ir.ConstInt(32, DataType.INT32, span)
+        tile_type = ir.TileType([dim16, dim32], DataType.FP16)
+        tile_var = ir.Var("tile", tile_type, span)
+
+        tile_arg = pl.Tile(expr=tile_var)
+        with pytest.warns(UserWarning, match="pad_value has no effect"):
+            pl.tile.slice(tile_arg, [8, 16], [0, 0], pad_value=pl.PadValue.zero)
+
     def test_tile_reshape(self):
         """Test tile.reshape operation."""
         span = ir.Span.unknown()