Make parent_idx a dispensable output for beam_search op to support models saved by older paddle version. (#16106)

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* Revert "Optimze Gelu with MKL Erf function (#15770)"

This reverts commit 676995c8.

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* Optimize for gelu operator

* Set up the low accuracy mode of MKL ERF function.

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* Only enable MKLML ERF when OS is linux

* Use the speical mklml version included vmsErf function to verify gelu mkl kernel.

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* Add the CUDA macro to avoid NVCC's compile issue.

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* Add the TODO comments for mklml library modification.

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* Clean Code

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* Add the comment of marco for NVCC compiler.

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* Refine beam_search_op to output an extra parent_idx tensor.
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* Fix the unittest test_beam_search_op.
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* Fix the merging mistake.
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* Refine the beam_search op and test.

* A basic CUDA implementation of beam_search for small batch_size.

* Implement CUDA kernel for beam_search_op.

* Use multiple CUDA threads in the same block to select the top beam.

* Update the python api of beam_search op.

* Enable extend function in CPU kernel of beam_search op.

* Unify the CUDA codes.
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* Unify the CPU kernel of beam_search op.

* Ensure the seletced items of beam_search_op's CPU kernel sorted by scores.

* Update the description of beam_search in API.spec.

* Enable the use of CUDA kernel in beam_search op.

* Exclude the beam_search's CUDA unittest when there is no CUDA gpu, and delete some debuging statements.
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* Follow comments.
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* Call the CPU kernel for beam_search op when batch_size > 4.
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* Remove the except of is_empty op in PrepareData.
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* nce add check sample lables, test=develop

* mem opt

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* refine code  test=develop

* refine code  test=develop

* refine code  test=develop

* refine code  test=develop

* refine with cub test=develop

* fix mkldnn test && remove comments && test=develop

* polish code && test=develop

* add only_forward test && test=develop

* refactor tree2col operator with new memory mechanism test=develop

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* Modified API according to panyx0718 test=develop

* fix API change according to heavengate test=develop

* Modify API comment test=develop

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* clip softmax for fp16

* updates

* fuse xent support fp16 test=develop

* wip

* wip

* add simple row reduce

* wip fp16 accurate softmax

* add accurate softmax kernel for fp16 test=develop

* update test=develop

* fix cpu build test=develop

* update api.spec test=develop

* follow comments test=develop

* fix build test=develop

* fix trt build test=develop

* fix inference build test=develop

* fix merge test=develop

* update test=develop

* try fix build test=develop

* fix build test=develop

* rename real_exp test=develop

* fortest

* remove hacky kernels test=develop

* clean up test=develop

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* refine tensor
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* refine tensor
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* fix device_context log
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* Add Temporal Allocator

* add Temporay Allocator to DeviceContext
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* code refine
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* fix mean_iou
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* Add DeviceTemporaryAllocator
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* fix conv_op bug
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* small fix
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* code refine
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* log refine
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* fix unit test
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* move double check

* refine concat_and_split
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* add limit_of_temporary_allocation
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* fix name
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