message: Do not assign the default layout in case of rank 1 -> effective rank 1 reshapes
diff: @@ -741,6 +741,11 @@ std::unique_ptr<Layout> LayoutAssignment::ChooseOperandLayoutFromOutputLayout(
  // layouts. So if 'output_layout' is the default layout, try if the
  // reshape is a bitcast when using the same layout. This may avoid copy
  // operations.
  + if (ShapeUtil::TrueRank(operand->shape()) == 1 &&
  + ShapeUtil::Rank(instruction->shape()) == 1) {
  + // Don't assign a layout in case of R1 -> effective R1 reshape.
  + return nullptr;
  + }
  const Shape& output_shape = instruction->shape();
  Shape output_shape_with_layout = ShapeUtil::MakeShapeWithLayout(
  output_shape.element_type(), AsInt64Slice(output_shape.dimensions()),
  @@ -800,6 +805,11 @@ std::unique_ptr<Layout> LayoutAssignment::ChooseOutputLayoutFromOperandLayout(
  // layouts. So if 'operand_layout' is the default layout, try if the
  // reshape is a bitcast when using the same layout. This may avoid copy
  // operations.
  + if (ShapeUtil::Rank(operand->shape()) == 1 &&
  + ShapeUtil::TrueRank(user->shape()) == 1) {
  + // Don't assign a layout in case of R1 -> effective R1 reshape.
  + return nullptr;
  + }
  Shape operand_shape_with_layout = ShapeUtil::MakeShapeWithLayout(
  operand->shape().element_type(),
  AsInt64Slice(operand->shape().dimensions()),
  