Created by: chengduoZH

This PR's work includes:

1. Add call stack info during compile time.
2. Extract the common code of run time and compile time to operator_call_stack.

Before

Traceback (most recent call last):
  File "./train_gpu_paddle.py", line 471, in <module>
    train(n_token, cutoffs)
  File "./train_gpu_paddle.py", line 254, in train
    decr_ratio=FLAGS.decr_ratio)
  File "/ssd3/transformer-xl-paddlepaddle_tmp/optimization.py", line 151, in optimization
    _, param_grads = optimizer.minimize(loss)
  File "</usr/local/lib/python2.7/dist-packages/decorator.pyc:decorator-gen-20>", line 2, in minimize
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/wrapped_decorator.py", line 25, in __impl__
    return wrapped_func(*args, **kwargs)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/dygraph/base.py", line 86, in __impl__
    return func(*args, **kwargs)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/optimizer.py", line 594, in minimize
    no_grad_set=no_grad_set)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/optimizer.py", line 493, in backward
    no_grad_set, callbacks)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/backward.py", line 706, in append_backward
    _append_backward_vars_(root_block, fwd_op_num, grad_to_var, grad_info_map)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/backward.py", line 518, in _append_backward_vars_
    op_desc.infer_shape(block.desc)
paddle.fluid.core_avx.EnforceNotMet: Invoke operator elementwise_add_grad error.

Input(Out@GRAD) should not be null at [../paddle/fluid/operators/elementwise/elementwise_op.h:289]
PaddlePaddle Call Stacks:
0       0x7fb76db1b35ap void paddle::platform::EnforceNotMet::Init<char const*>(char const*, char const*, int) + 506
1       0x7fb76db1c065p paddle::platform::EnforceNotMet::EnforceNotMet(std::__exception_ptr::exception_ptr, char const*, int) + 165
2       0x7fb76f427ebap paddle::operators::ElementwiseOpExplicitGrad::InferShape(paddle::framework::InferShapeContext*) const + 1130
3       0x7fb76dcdf605p
4       0x7fb76dce3ed9p paddle::framework::OpDesc::InferShape(paddle::framework::BlockDesc const&) const + 985
5       0x7fb76dc00334p
6       0x7fb76db4eb14p
7             0x4c5326p PyEval_EvalFrameEx + 37958
8             0x4b9b66p PyEval_EvalCodeEx + 774
9             0x4c1f56p PyEval_EvalFrameEx + 24694
10            0x4b9b66p PyEval_EvalCodeEx + 774
11            0x4c17c6p PyEval_EvalFrameEx + 22758
12            0x4b9b66p PyEval_EvalCodeEx + 774
13            0x4c17c6p PyEval_EvalFrameEx + 22758
14            0x4b9b66p PyEval_EvalCodeEx + 774
15            0x4d57a3p
16            0x4a587ep PyObject_Call + 62
17            0x4be51ep PyEval_EvalFrameEx + 9790
18            0x4b9b66p PyEval_EvalCodeEx + 774
19            0x4d57a3p

Now:

Traceback (most recent call last):
  File "./train_gpu_paddle.py", line 471, in <module>
    train(n_token, cutoffs)
  File "./train_gpu_paddle.py", line 254, in train
    decr_ratio=FLAGS.decr_ratio)
  File "/ssd3/transformer-xl-paddlepaddle_tmp/optimization.py", line 151, in optimization
    _, param_grads = optimizer.minimize(loss)
  File "</usr/local/lib/python2.7/dist-packages/decorator.pyc:decorator-gen-20>", line 2, in minimize
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/wrapped_decorator.py", line 25, in __impl__
    return wrapped_func(*args, **kwargs)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/dygraph/base.py", line 86, in __impl__
    return func(*args, **kwargs)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/optimizer.py", line 594, in minimize
    no_grad_set=no_grad_set)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/optimizer.py", line 493, in backward
    no_grad_set, callbacks)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/backward.py", line 706, in append_backward
    _append_backward_vars_(root_block, fwd_op_num, grad_to_var, grad_info_map)
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/backward.py", line 518, in _append_backward_vars_
    op_desc.infer_shape(block.desc)
paddle.fluid.core_avx.EnforceNotMet: Invoke operator elementwise_add_grad error.

Python Callstacks:
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/framework.py", line 1776, in append_op
    attrs=kwargs.get("attrs", None))
  File "/ssd3/zcd_Paddle/build_fast/python/paddle/fluid/layers/math_op_patch.py", line 149, in __impl__
    attrs={'axis': axis})
  File "/ssd3/transformer-xl-paddlepaddle_tmp/model.py", line 371, in gather_nd
    index_join = raw_index * tensor.shape[1] + col_index
  File "/ssd3/transformer-xl-paddlepaddle_tmp/model.py", line 403, in _gather_logprob
    return gather_nd(logprob, idx)
  File "/ssd3/transformer-xl-paddlepaddle_tmp/model.py", line 494, in mask_adaptive_logsoftmax
    _gather_logprob(tail_logprob, cur_target))
  File "/ssd3/transformer-xl-paddlepaddle_tmp/model.py", line 558, in transformer
    proj_same_dim=proj_same_dim)
  File "/ssd3/transformer-xl-paddlepaddle_tmp/transformer_xl.py", line 200, in _build_model
    name='encoder'
  File "./train_gpu_paddle.py", line 84, in model_fn
    loss, new_mems = transofrmer_xl._build_model()
  File "./train_gpu_paddle.py", line 99, in single_core_graph
    is_training=is_training)
  File "./train_gpu_paddle.py", line 128, in create_model
    mems=mems)
  File "./train_gpu_paddle.py", line 238, in train
    batch_size=bsz_per_trainner, n_token=n_token, cutoffs=cutoffs)
  File "./train_gpu_paddle.py", line 471, in <module>
    train(n_token, cutoffs)
C++ Callstacks:
Input(Out@GRAD) should not be null at [../paddle/fluid/operators/elementwise/elementwise_op.h:289]
PaddlePaddle Call Stacks:
0       0x7fb76db1b35ap void paddle::platform::EnforceNotMet::Init<char const*>(char const*, char const*, int) + 506
1       0x7fb76db1c065p paddle::platform::EnforceNotMet::EnforceNotMet(std::__exception_ptr::exception_ptr, char const*, int) + 165
2       0x7fb76f427ebap paddle::operators::ElementwiseOpExplicitGrad::InferShape(paddle::framework::InferShapeContext*) const + 1130
3       0x7fb76dcdf605p
4       0x7fb76dce3ed9p paddle::framework::OpDesc::InferShape(paddle::framework::BlockDesc const&) const + 985
5       0x7fb76dc00334p
6       0x7fb76db4eb14p
7             0x4c5326p PyEval_EvalFrameEx + 37958
8             0x4b9b66p PyEval_EvalCodeEx + 774
9             0x4c1f56p PyEval_EvalFrameEx + 24694
10            0x4b9b66p PyEval_EvalCodeEx + 774
11            0x4c17c6p PyEval_EvalFrameEx + 22758
12            0x4b9b66p PyEval_EvalCodeEx + 774