Support PyTorch grid_sample

include/tvm/relay/attrs/image.h

@@ -275,6 +275,7 @@ struct AffineGridAttrs : public tvm::AttrsNode<AffineGridAttrs> {
 struct GridSampleAttrs : public tvm::AttrsNode<GridSampleAttrs> {
   String method;
   String layout;
+  String padding_mode;
 
   TVM_DECLARE_ATTRS(GridSampleAttrs, "relay.attrs.GridSampleAttrs") {
     TVM_ATTR_FIELD(method)
@@ -287,6 +288,11 @@ struct GridSampleAttrs : public tvm::AttrsNode<GridSampleAttrs> {
         "'N', 'C', 'H', 'W' stands for batch, channel, height, and width"
         "dimensions respectively. Resize is applied on the 'H' and"
         "'W' dimensions.");
+    TVM_ATTR_FIELD(padding_mode)
+        .set_default("zeros")
+        .describe(
+            "Specify the padding mode to use."
+            "zeros, border etc.");
   }
 };
 

python/tvm/relay/frontend/pytorch.py

@@ -2896,6 +2896,25 @@ def mv(self, inputs, _):
         # Chop off the extra result dimension
         return _op.transform.squeeze(dense_result)
 
+    def grid_sampler(self, inputs, input_types):
+        if inputs[2] == 0:
+            mode = "bilinear"
+        else:
+            msg = "Only bilinear mode is supported in grid_sampler"
+            raise NotImplementedError(msg)
+
+        if inputs[3] == 0:
+            padding_mode = "zeros"
+        elif inputs[3] == 1:
+            padding_mode = "border"
+        else:
+            msg = "Only zeros and border padding mode are supported in grid_sampler"
+            raise NotImplementedError(msg)
+
+        axes = [0, 3, 1, 2]
+        grid = _op.transform.transpose(inputs[1], axes)
+        return _op.image.grid_sample(inputs[0], grid, mode, "NCHW", padding_mode)
+
     # Operator mappings
     def create_convert_map(self):
         self.convert_map = {
@@ -3124,6 +3143,7 @@ def create_convert_map(self):
             "aten::einsum": self.einsum,
             "aten::dot": self.dot,
             "aten::mv": self.mv,
+            "aten::grid_sampler": self.grid_sampler,
         }
 
     def update_convert_map(self, custom_map):

python/tvm/relay/op/image/_image.py

@@ -365,7 +365,8 @@ def affine_grid_func(attrs, inputs, _):
 def compute_grid_sample(attrs, inputs, out_dtype):
     method = attrs.method
     layout = attrs.layout
-    return [topi.image.grid_sample(inputs[0], inputs[1], method, layout)]
+    padding_mode = attrs.padding_mode
+    return [topi.image.grid_sample(inputs[0], inputs[1], method, layout, padding_mode)]
 
 
 reg.register_injective_schedule("image.grid_sample")

python/tvm/relay/op/image/image.py

@@ -455,7 +455,7 @@ def affine_grid(data, target_shape=None):
     return _make.affine_grid(data, target_shape)
 
 
-def grid_sample(data, grid, method="bilinear", layout="NCHW"):
+def grid_sample(data, grid, method="bilinear", layout="NCHW", padding_mode="zeros"):
     """Applies bilinear sampling to input feature map.
 
     Given :math:`data` and :math:`grid`, then the output is computed by
@@ -468,7 +468,8 @@ def grid_sample(data, grid, method="bilinear", layout="NCHW"):
 
     :math:`x_{dst}`, :math:`y_{dst}` enumerate all spatial locations in :math:`output`, and
     :math:`G()` denotes the interpolation function.
-    The out-boundary points will be padded with zeros. The shape of the output will be
+    The out-boundary points will be padded with zeros if padding_mode is "zeros".
+    The shape of the output will be
     (data.shape[0], data.shape[1], grid.shape[2], grid.shape[3]).
 
     The operator assumes that :math:`grid` has been normalized to [-1, 1].
@@ -489,9 +490,12 @@ def grid_sample(data, grid, method="bilinear", layout="NCHW"):
     layout : str
         The layout of input data and the output.
 
+    padding_mode : str
+        The padding mode for outside grid values.
+
     Returns
     -------
     Output : tvm.Tensor
         4-D with shape [batch, 2, out_height, out_width]
     """
-    return _make.grid_sample(data, grid, method, layout)
+    return _make.grid_sample(data, grid, method, layout, padding_mode)

python/tvm/topi/image/grid_sample.py

@@ -59,7 +59,7 @@ def _compute(n, dim, i, j):
     return te.compute(oshape, _compute, tag="affine_grid")
 
 
-def grid_sample(data, grid, method="bilinear", layout="NCHW"):
+def grid_sample(data, grid, method="bilinear", layout="NCHW", padding_mode="zeros"):
     """Applies bilinear sampling to input feature map.
 
     Given :math:`data` and :math:`grid`, assuming NCHW layout, then the output is computed by
@@ -72,7 +72,8 @@ def grid_sample(data, grid, method="bilinear", layout="NCHW"):
 
     :math:`x_{dst}`, :math:`y_{dst}` enumerate all spatial locations in :math:`output`, and
     :math:`G()` denotes the interpolation method.
-    The out-boundary points will be padded with zeros. The shape of the output will be
+    The out-boundary points will be padded with zeros if the padding_mode is "zeros".
+    The shape of the output will be
     (data.shape[0], data.shape[1], grid.shape[2], grid.shape[3]).
 
     The operator assumes that :math:`grid` has been normalized to [-1, 1].
@@ -96,19 +97,26 @@ def grid_sample(data, grid, method="bilinear", layout="NCHW"):
     Returns
     -------
     Output : tvm.Tensor
-        4-D with shape [batch, 2, out_height, out_width]
+        4-D with shape [batch, in_channel, out_height, out_width]
     """
     batch, in_channel, in_height, in_width = data.shape
     out_height, out_width = grid.shape[2:]
     assert method == "bilinear", "Only bilinear is supported"
     assert layout == "NCHW", "Only NCHW is supported"
 
     def _get_pixel_value(n, c, h, w):
-        return te.if_then_else(
-            te.all(h >= 0, w >= 0, h < in_height, w < in_width),
-            data[n, c, h, w],
-            tir.const(0.0, dtype=data.dtype),
-        )
+        if padding_mode == "zeros":
+            return te.if_then_else(
+                te.all(h >= 0, w >= 0, h < in_height, w < in_width),
+                data[n, c, h, w],
+                tir.const(0.0, dtype=data.dtype),
+            )
+        if padding_mode == "border":
+            h_b = te.max(te.min(h, in_height - 1), 0)
+            w_b = te.max(te.min(w, in_width - 1), 0)
+            return data[n, c, h_b, w_b]
+
+        raise AssertionError("unsupported padding_mode")
 
     def _bilinear_sample(n, c, h, w):
         x = grid[n, 0, h, w]

python/tvm/topi/testing/grid_sample_python.py

@@ -29,36 +29,71 @@ def affine_grid_python(data, target_shape):
     return data.reshape(-1, 3).dot(grid).reshape(data.shape[0], 2, *target_shape)
 
 
-def _bilinear_sample_nchw_python(data, grid):
+def _bilinear_sample_nchw_python(data, grid, padding_mode):
     batch, in_channel, in_height, in_width = data.shape
     _, _, out_height, out_width = grid.shape
     out = np.zeros((batch, in_channel, out_height, out_width), dtype=data.dtype)
 
     def _within_bound(y, x):
         return 0 <= y < in_height and 0 <= x < in_width
 
-    for n in range(0, batch):
-        for h in range(0, out_height):
-            for w in range(0, out_width):
-                x, y = grid[n, :, h, w]
-                y = (y + 1) * (in_height - 1) / 2
-                x = (x + 1) * (in_width - 1) / 2
-                y0 = int(math.floor(y))
-                x0 = int(math.floor(x))
-                y1 = y0 + 1
-                x1 = x0 + 1
-                if _within_bound(y0, x0):
-                    out[n, :, h, w] += data[n, :, y0, x0] * (1.0 - (y - y0)) * (1.0 - (x - x0))
-                if _within_bound(y0, x1):
+    def compute_padding_mode_zeros():
+        for n in range(0, batch):
+            for h in range(0, out_height):
+                for w in range(0, out_width):
+                    x, y = grid[n, :, h, w]
+                    y = (y + 1) * (in_height - 1) / 2
+                    x = (x + 1) * (in_width - 1) / 2
+                    y0 = int(math.floor(y))
+                    x0 = int(math.floor(x))
+                    y1 = y0 + 1
+                    x1 = x0 + 1
+                    if _within_bound(y0, x0):
+                        out[n, :, h, w] += data[n, :, y0, x0] * (1.0 - (y - y0)) * (1.0 - (x - x0))
+                    if _within_bound(y0, x1):
+                        out[n, :, h, w] += data[n, :, y0, x1] * (1.0 - (y - y0)) * (x - x0)
+                    if _within_bound(y1, x0):
+                        out[n, :, h, w] += data[n, :, y1, x0] * (y - y0) * (1.0 - (x - x0))
+                    if _within_bound(y1, x1):
+                        out[n, :, h, w] += data[n, :, y1, x1] * (y - y0) * (x - x0)
+
+        return out
+
+    def get_pixel_value(x, x_max):
+        return max(min(x, x_max - 1), 0)
+
+    def compute_padding_mode_border():
+        for n in range(0, batch):
+            for h in range(0, out_height):
+                for w in range(0, out_width):
+                    x, y = grid[n, :, h, w]
+                    y = (y + 1) * (in_height - 1) / 2
+                    x = (x + 1) * (in_width - 1) / 2
+                    y0 = int(math.floor(y))
+                    x0 = int(math.floor(x))
+                    y1 = y0 + 1
+                    x1 = x0 + 1
+                    y0 = get_pixel_value(y0, in_height)
+                    y1 = get_pixel_value(y1, in_height)
+                    x0 = get_pixel_value(x0, in_width)
+                    x1 = get_pixel_value(x1, in_width)
+                    out[n, :, h, w] = data[n, :, y0, x0] * (1.0 - (y - y0)) * (1.0 - (x - x0))
                     out[n, :, h, w] += data[n, :, y0, x1] * (1.0 - (y - y0)) * (x - x0)
-                if _within_bound(y1, x0):
                     out[n, :, h, w] += data[n, :, y1, x0] * (y - y0) * (1.0 - (x - x0))
-                if _within_bound(y1, x1):
                     out[n, :, h, w] += data[n, :, y1, x1] * (y - y0) * (x - x0)
-    return out
 
+        return out
+
+    if padding_mode == "zeros":
+        return compute_padding_mode_zeros()
+    if padding_mode == "border":
+        return compute_padding_mode_border()
 
-def grid_sample_nchw_python(data, grid, method="bilinear"):
+    raise ValueError("invalid padding_mode")
+
+
+def grid_sample_nchw_python(data, grid, method="bilinear", padding_mode="zeros"):
     if method == "bilinear":
-        return _bilinear_sample_nchw_python(data, grid)
+        return _bilinear_sample_nchw_python(data, grid, padding_mode)
+
     raise ValueError("invalid method")

src/relay/op/image/grid_sample.cc

@@ -116,10 +116,11 @@ bool GridSampleRel(const Array<Type>& types, int num_inputs, const Attrs& attrs,
 
 // Positional relay function to create affine_grid operator
 // used by frontend FFI.
-Expr MakeGridSample(Expr data, Expr grid, String method, String layout) {
+Expr MakeGridSample(Expr data, Expr grid, String method, String layout, String padding_mode) {
   auto attrs = make_object<GridSampleAttrs>();
   attrs->method = std::move(method);
   attrs->layout = std::move(layout);
+  attrs->padding_mode = std::move(padding_mode);
   static const Op& op = Op::Get("image.grid_sample");
   return Call(op, {data, grid}, Attrs(attrs), {});
 }

tests/python/frontend/pytorch/test_forward.py

@@ -216,9 +216,8 @@ def verify_model(
             if not tvm.runtime.enabled(target):
                 continue
             dev = tvm.device(target, 0)
-            relay_graph, relay_lib, relay_params = relay.build(mod, target=target, params=params)
-            relay_model = graph_executor.create(relay_graph, relay_lib, dev)
-            relay_model.set_input(**relay_params)
+            lib = relay.build(mod, target=target, params=params)
+            relay_model = graph_executor.GraphModule(lib["default"](dev))
             for name, inp in compiled_input.items():
                 relay_model.set_input(name, inp)
             relay_model.run()
@@ -4079,5 +4078,45 @@ def test_fn(m, v):
     verify_model(test_fn, [torch.randn(3, 8), torch.randn(8)])
 
 
+def test_grid_sample():
+    class Grid_sample_zeros(Module):
+        def forward(self, x, y):
+            return torch.nn.functional.grid_sample(
+                input=x, grid=y, mode="bilinear", padding_mode="zeros", align_corners=True
+            )
+
+    class Grid_sample_border(Module):
+        def forward(self, x, y):
+            return torch.nn.functional.grid_sample(
+                input=x, grid=y, mode="bilinear", padding_mode="border", align_corners=True
+            )
+
+    data = torch.rand([4, 4, 16, 32]).float()
+    grid = torch.rand([4, 8, 8, 2]).float()
+    verify_model(Grid_sample_zeros(), input_data=[data, grid])
+    verify_model(Grid_sample_border(), input_data=[data, grid])
+
+
+def test_list_tuple():
+    """test compilation error for a Python list followed by a prim::TupleConstruct."""
+
+    class List_tuple(Module):
+        def forward(self, x):
+            merged = []
+            mask_list = []
+            for i in range(3):
+                w0 = torch.sigmoid(x)
+                merged.append((w0, w0))
+                mask_list.append(x)
+
+            for i in range(3):
+                merged[i] = merged[i][0] + merged[i][1]
+            return mask_list[2], merged
+
+    x = torch.rand([4, 4, 16, 32]).float()
+    script_module = torch.jit.trace(List_tuple(), x, strict=False).eval()
+    mod, params = relay.frontend.from_pytorch(script_module, [("x", x.shape)])
+
+
 if __name__ == "__main__":
     pytest.main([__file__])

tests/python/relay/test_op_level5.py

@@ -1392,20 +1392,24 @@ def verify_affine_grid(num_batch, target_shape):
 
 @tvm.testing.uses_gpu
 def test_grid_sample():
-    def verify_grid_sample(data_shape, grid_shape):
+    def verify_grid_sample(data_shape, grid_shape, padding_mode="zeros"):
         dtype = "float32"
         batch, channel, _, _ = data_shape
         _, _, out_height, out_width = grid_shape
         data = relay.var("data", relay.ty.TensorType(data_shape, dtype))
         grid = relay.var("grid", relay.ty.TensorType(grid_shape, dtype))
-        y = relay.image.grid_sample(data, grid, method="bilinear", layout="NCHW")
+        y = relay.image.grid_sample(
+            data, grid, method="bilinear", layout="NCHW", padding_mode=padding_mode
+        )
         yy = run_infer_type(y)
         assert yy.checked_type == relay.TensorType((batch, channel, out_height, out_width), dtype)
         func = relay.Function([data, grid], y)
 
         data_np = np.random.uniform(size=data_shape).astype(dtype)
         grid_np = np.random.uniform(size=grid_shape, low=-1.5, high=1.5).astype(dtype)
-        ref_res = tvm.topi.testing.grid_sample_nchw_python(data_np, grid_np, method="bilinear")
+        ref_res = tvm.topi.testing.grid_sample_nchw_python(
+            data_np, grid_np, method="bilinear", padding_mode=padding_mode
+        )
 
         for target, dev in tvm.testing.enabled_targets():
             for kind in ["graph", "debug"]:
@@ -1416,6 +1420,8 @@ def verify_grid_sample(data_shape, grid_shape):
 
     verify_grid_sample((4, 4, 16, 32), (4, 2, 8, 8))
     verify_grid_sample((4, 4, 16, 32), (4, 2, 32, 32))
+    verify_grid_sample((4, 4, 16, 32), (4, 2, 8, 8), "border")
+    verify_grid_sample((4, 4, 16, 32), (4, 2, 32, 32), "border")
 
 
 @tvm.testing.uses_gpu

tests/python/topi/python/test_topi_image.py

@@ -274,18 +274,20 @@ def check_target(target, dev):
 
 @tvm.testing.uses_gpu
 def test_grid_sample():
-    def verify_grid_sample(data_shape, grid_shape):
+    def verify_grid_sample(data_shape, grid_shape, padding_mode="zeros"):
         dtype = "float32"
         data = te.placeholder(data_shape, dtype=dtype)
         grid = te.placeholder(grid_shape, dtype=dtype)
-        out = topi.image.grid_sample(data, grid, "bilinear")
+        out = topi.image.grid_sample(data, grid, "bilinear", padding_mode=padding_mode)
 
         @memoize("topi.tests.test_grid_sample.verify_grid_sample")
         def get_ref_data():
             data_np = np.random.uniform(size=data_shape).astype(dtype)
             # allow grid values to be out-of-bound
             grid_np = np.random.uniform(size=grid_shape, low=-1.5, high=1.5).astype(dtype)
-            out_np = tvm.topi.testing.grid_sample_nchw_python(data_np, grid_np, "bilinear")
+            out_np = tvm.topi.testing.grid_sample_nchw_python(
+                data_np, grid_np, "bilinear", padding_mode
+            )
             return data_np, grid_np, out_np
 
         data_np, grid_np, out_np = get_ref_data()
@@ -306,7 +308,8 @@ def check_target(target, dev):
             check_target(target, dev)
 
     verify_grid_sample((4, 4, 16, 32), (4, 2, 8, 8))
-    verify_grid_sample((4, 4, 16, 32), (4, 2, 32, 32))
+    verify_grid_sample((4, 4, 16, 32), (4, 2, 32, 32), "border")
+    verify_grid_sample((4, 4, 16, 32), (4, 2, 8, 8), "border")
 
 
 if __name__ == "__main__":