Lowering for upsample_bicubic2d

test/test_torchinductor.py

@@ -2175,6 +2175,15 @@ def fn(a, b):
             check_lowp=False,
         )
 
+    def test_upsample_bicubic2d(self):
+        def fn(a):
+            return (
+                aten.upsample_bicubic2d(a, (128, 128), True),
+                aten.upsample_bicubic2d(a, (128, 256), False),
+            )
+
+        self.common(fn, (torch.randn([4, 3, 64, 32], dtype=torch.float32),))
+
     def test_sort(self):
         def fn(a):
             return torch.sort(a)

torchinductor/lowering.py

@@ -62,6 +62,7 @@ def add_needs_realized_inputs(fn):
         aten.mm,
         aten.upsample_bilinear2d,
         aten.upsample_nearest2d,
+        aten.upsample_bicubic2d,
     ]
 )
 
@@ -953,7 +954,6 @@ def inner_fn(index):
 make_fallback(aten.topk)
 make_fallback(aten.unfold)
 make_fallback(aten.unfold_backward)
-make_fallback(aten.upsample_bicubic2d)
 make_fallback(aten.upsample_bicubic2d_backward)
 make_fallback(aten.upsample_bilinear2d_backward)
 
@@ -1718,6 +1718,115 @@ def fn(idx):
     )
 
 
+@register_lowering(aten.upsample_bicubic2d)
+def upsample_bicubic2d(x, output_size, align_corners, scales_h=None, scales_w=None):
+    x.realize_hint()
+    x_loader = x.make_loader()
+
+    N, C, iH, iW = x.get_size()
+    oH, oW = output_size
+
+    iH = V.graph.sizevars.guard_static_shape(iH)
+    iW = V.graph.sizevars.guard_static_shape(iW)
+
+    def get_int_dtype(maxval):
+        if maxval > torch.iinfo(torch.int32).max:
+            return torch.int64
+        return torch.int32
+
+    def compute_scale(in_size, out_size, align_corners, scale=None):
+        if align_corners:
+            return (in_size - 1) / (out_size - 1) if out_size > 1 else 0
+        else:
+            return 1 / scale if scale is not None and scale > 0 else in_size / out_size
+
+    def compute_source_index(scale, dst_index, align_corners):
+        dst_index_ie = ops.index_expr(dst_index, torch.float32)
+        if align_corners:
+            return ops.mul(scale, dst_index_ie)
+        else:
+            return ops.sub(
+                ops.mul(scale, ops.add(dst_index_ie, 0.5)), 0.5
+            )  # scale * (dst_index + 0.5) - 0.5
+
+    def cubic_convolution1(x, A):
+        # ((A + 2) * x - (A+3)) * x * x + 1
+        return ops.add(ops.mul(ops.mul(ops.sub(ops.mul(A + 2, x), A + 3), x), x), 1.0)
+
+    def cubic_convolution2(x, A):
+        # ((A * x - 5 * A) * x + 8 * A) * x - 4*A
+        return ops.sub(
+            ops.mul(ops.add(ops.mul(ops.sub(ops.mul(A, x), 5 * A), x), 8 * A), x), 4 * A
+        )
+
+    def get_cubic_upsample_coefficients(t):
+        A = -0.75
+        c0 = cubic_convolution2(ops.add(t, 1.0), A)
+        c1 = cubic_convolution1(t, A)
+
+        x2 = ops.sub(1.0, t)
+        c2 = cubic_convolution1(x2, A)
+        c3 = cubic_convolution2(ops.add(x2, 1.0), A)
+        return (
+            c0,
+            c1,
+            c2,
+            c3,
+        )
+
+    def cubic_interp1d(xs, t):
+        cs = get_cubic_upsample_coefficients(t)
+        # dot product between xs and cs
+        return ops.add(
+            ops.mul(xs[0], cs[0]),
+            ops.add(
+                ops.mul(xs[1], cs[1]),
+                ops.add(ops.mul(xs[2], cs[2]), ops.mul(xs[3], cs[3])),
+            ),
+        )
+
+    height_scale = compute_scale(iH, oH, align_corners, scales_h)
+    width_scale = compute_scale(iW, oW, align_corners, scales_h)
+
+    def clamp(v, min, max):
+        return ops.maximum(min, ops.minimum(max, v))
+
+    def fn(idx):
+        n, c, oy, ox = idx
+
+        real_x = compute_source_index(width_scale, ox, align_corners)
+        in_x = ops.floor(real_x)
+        t_x = ops.sub(real_x, in_x)
+
+        real_y = compute_source_index(height_scale, oy, align_corners)
+        in_y = ops.floor(real_y)
+        t_y = ops.sub(real_y, in_y)
+
+        def load_bounded(fy, fx):
+            iy = ops.indirect_indexing(clamp(fy, 0, iH - 1))
+            ix = ops.indirect_indexing(clamp(fx, 0, iW - 1))
+            return x_loader([n, c, iy, ix])
+
+        iy = ops.to_dtype(in_y, get_int_dtype(iH + 1))
+        ix = ops.to_dtype(in_x, get_int_dtype(iW + 1))
+        iys_ofs = tuple((ops.add(iy, ofs) for ofs in (-1, 0, 1, 2)))
+        ixs_ofs = tuple((ops.add(ix, ofs) for ofs in (-1, 0, 1, 2)))
+
+        def get_x_interp(y):
+            coeffs_x = tuple((load_bounded(y, x) for x in ixs_ofs))
+            return cubic_interp1d(coeffs_x, t_x)
+
+        coeffs_y = tuple(get_x_interp(y) for y in iys_ofs)
+        return cubic_interp1d(coeffs_y, t_y)
+
+    return Pointwise.create(
+        device=x.get_device(),
+        dtype=x.get_dtype(),
+        inner_fn=fn,
+        ranges=[N, C, sympy.Integer(oH), sympy.Integer(oW)],
+    )
+
+
 @register_lowering(aten.reflection_pad2d)
 def reflection_pad2d(x, padding):
     assert len(padding) == 4