// dimension, which can vary based on data layout, etc.
//
// The extent of `broadcast_from` dim0 must be equal to the extent of the
// feature_dim of `broadcast_to`.
//
// Example:
//   [1x2x3x4], [2], 1 -> [1x2x3x4]
// TODO(laurenzo): Swap the order of broadcast_to and broadcast_from for
// consistency. Possibly also rename for clarity.
static Value Broadcast1DToFeatureDim(Location loc, Value broadcast_to,