* flatten op support 0D-tensor

* add test in zero dim py

* fix shape should be list

* short code for ci-coverage

* add backward test

* simple code for ci coverage

* add axis check

* add 0D-tensor test in test_flatten_contiguous_range_op.py

* add axis error test for Coverage CI

* add more test for CI-Coverage

* add more test for CI-Coverage

* support 0D for paddle.sort/argsort

* support 0D tensor for paddle.sort/argsort in xpu

* fix bug

* fix grad and add value assertion

* Use BroadcastKernel and ReduceKernel to optimize expand and expand_grad.

* Correct the axis when there is only 1 input in BroadcastKernel.

* Add the calculate of output's shape.

This reverts commit 9df0ab32.

* add 0-d support for paddle.kthvalue

* add 0-d support for paddle.mode

* fix coverage test for device

* [Zero-Dim] Support 0D for paddle.diagflat

* rename some kernel name

* fix compile problem

* rm dependence to "convert_utils.h" in some files

* fix bugs

* replace DataType2String with DataTypeToString

* replace framework::DataTypeSize with phi::SizeOf

* mv convert_function from fluid to phi and rm old map

* recommit with pre-commit

* repalce ProtoVarType with ProtoDataType and update comment.

* fix error about include "dnnl.hpp"

* revert add dep mkldnn to convert_utils in phi

* add mkldnn deps in convert_utils.h in phi

* move deps to convert_utils.h in phi

* standard api

* fix xpu bugs

* [Zero-Dim] support input 0D Tensor for sundary api

* fix comment

* standard_api

* add hardtanh

* standard api

* fix ci bugs

* fix ci bugs

* fix ce bugs

* add unittest for einsum-v2-trace and diagonal

* repeat labels.

* einsum support repeated labels.

* forward is ok for diagonal and undiagonalized.
TODO: check backward is ok by our theorem.

* backward is ok!

* fix by PR suggestions.

* fix ci error

* fix ci error

* fix ci warning

* [Zero-Dim] support input 0D Tensor for unary api

* fix CI

* fix return order error and duplicate results with specific inputs

* fix split bug in static mode

* modify code style

* modify code style

* add unit test for split

* add save kernel

* add save_sr_kernel

* remove original save_op

* add save gpu kernel

* remove combine kernel

* add port.h include

* add save selected rows test

* remove useless kernel.h

* [OpAttr]ksize of pool2d support Tensor type

* fix unittest

* add unittest

* fix split bug

* solve function redefine

* fix fluid.layers.split and add unit test

* delete splitInferMeta register in unary.cc

* modify test_split_op GPU unit test

* modify test_split_op GPU unit test place param

* refactor split op and fix infershape bugs

* add () in && and ||

* fix split C++ unit test

* fix split infershape

* Adapt tensor axis for argmin/max

* Add UT

* Polish UT

* [OpAttr]Adapt tensor axis for reduce_min/max/mean/sum/prod

* [OpAttr]padding_value of Pad support Tensor type

* fix unittest

* fix unittest

* fix coverage

* remove fluid kernel and activate phi kernel

* fix parameter error

* transfer mkldnn part

* modify header file path

* fix compile error

* transfer special case

* fix lod setting and special case for layout setting

* add testcase and refine code

* [OpAttr]axis of Reverse Support Tensor type

* fix coverage

* fix unittest

* [OpAttr]Squeeze axes support Tensor

* add support_tensor

* fix unittest

* fix coverage

* make affine_grid_op support 5d_input on cpu and gpu