* Ported injective schedules to C++. Added some elementwise ops.

* Fix lint errors

* Added reduction ops and schedules

* Fix lint errors

* Fix lint errors

* Fix lint errors

* Added transform ops

* Fix lint errors

* Fix lint errors

* Added softmax, log_softmax, leaky_relu and flatten ops.
Fixed issue where TVM_DECLARE_INTRIN_UNARY used the PureExtern flag
instead of PureIntrinsic.
Added softmax CUDA schedule.

* Fix lint

* Fix lint

* Added binary_dense, batch_norm_inference, dense, dilate, scale_shift_*,
global_pool and pool ops.
Extended pad to allow specifying pad_value.
Fixed issue where pad would throw if padding was zero in all dimensions.

* Fix lint

* Fix lint

* Added CUDA schedules for dense, pool and global_pool

* Added extern schedules for generic and CUDA

* Fix lint

* Added x86 binary schedules

* Fix lint

* Added rocm dense schedule. Added rocBLAS and cuBLAS support to dense ops

* Added pow ops. Added x86 default and injective schedules

* Fix lint

* Fix lint

* Fix lint

* Fix lint

* Fix lint

* Fix indent

* Removed schedules directory

* Changed left_shift, right_shift to operators. Changed pad_value in pad() to remove pointer usage

* Fixed usage of pad in nn/pooling.h. Fixed declaration of operator>>

* Fixed comments for shift operators

* Added comments to utility functions

* Added TOPI C++ library, exporting broadcast_add op

* Fix lint

* Share libinfo.py with TVM

* Fix lint

* Add other broadcast ops

* Fix lint

* Fix imports in topi

* Fix lib names

* Fixed build issue where windows builds don't apply correct definitions

* Removed TVM_EXPORTS from topi library

* Attempted CI build fix

* Add topi lib to tvm_multilib

* Fix Jenkinsfile

* Added TOPI build target to Makefile

* Fix nn op namespaces.

* Fix lint

* Renamed TOPI lib to libtvm_topi

* Removed _ffi/base.py

* Remove _ffi from topi, now shared with tvm.

* Make libtvm_topi loading optional

* Fix compiler warnings

* Fix lint

* Fix lint

* Fix lint

* Fix build error by making new libs argument to Target optional

* Added C++ Target type interop. Added registration of remaining C++ ops and schedules. Added test of broadcast ops

* Fix lint

* Fix lint

* Fix compile error

* Fix compiler warnings

* Fix compiler warnings

* Fixed int vector interop. Fixed argmin incorrectly invoking argmax. Fixed corner case in default schedules of attempting to fuse 0 length axes. Added tests for reduce ops.

* Refactored reduce builders

* Fixed typos in topi.cc. Added basic test.

* Fixed padding size error. Added dense, dilate, pooling tests

* Fixed issue where clip would output a different dtype to the input. Added split_sections op to cover the other mode of the python split op. Added tests.

* Changed extension type numbers to avoid clash with NNVM

* Fix lint

* Fix compiler warnings

* Removed use of std::vector from the public TOPI API

* Fix lint

* Add TOPI C++ tests to CI

* Fixed detail namespacing. Improved comments.

* when there is no intrin func, using body for initialization. For issue 714.

* Refine code per review comments, and add a test case.

* Fix lint issues.

* Re-organize the tensorize test cases, and add a new case for none-reset
mode.

* Fix a typo.

* Delete the unit case because merged it into test_schedule_tensorize.py already.

* always use new tensor in its stage when rewrite for cache read

* revert previous changes to sync up with master

* support using the ptr with an original offset

* update test case and fix CI error

* Port build_module.py to C++

* Fix lint errors

* Fix more lint errors

* Fix more lint errors

* Fix more lint errors

* Fix build error

* Implemented style fixes

* Fix lint errors

* Added function to construct target from string
lower now returns array

* Fix lint error

* Implemented review changes - style & Target options -> std::vector

* Fixed lint, argument alignment and added unit test

* Changed test to target LLVM, fixed sign compare warnings

* Reverted unit test to CUDA, changed Jenkinsfile to enable GPU for C++ tests

* Slight change to Jenkinsfile

* Changed build_module test from CUDA to LLVM

* Added function var() to construct a Var instance.
Changed implementation of LLVMEnabled()

* Reverted Jenkinsfile

* Support rank-0 tensor

* fix lint

* Support vector operations for AMD (llvm IR)

* fix whitespace

* update comments, docstring

* [BUFFER] Smarter slice to detect compactness

* move simplify of begins early

[TOPI] Add broadcast and reduce operators

* [RUNTIME][PASS] Allow declare vector type array

* fix bcast

* [BUFFER] Enable vload/store function in buffer

* ok

* [GRAPH] Add GraphHandle

* Move to apps/graph_executor

* [STORAGE][BUFFER] Support access ptr for clear access pattern.

* fix lint

* [C API] Make DSL API registerable, add copy from/to raw bytes

* fix cython

* [CODEGEN/PASS] add restricted, alignment option

* fix lint

* Fix the alloca

* [IR] Add body to AssertStmt

* fix lint

* [OP] Initial start of op library

* add gtest

* Support for batch ComputeOp

* Support for batch ComputeOp

* Fix CrossThreadReduction

* Fix lint

* Add UpdateArray, remove support for batch reduce

* Tuple input support for reduce

* rfactor works with multiple reducer; support multiple reducers with different types

* Small fix

* Small fix

* Change return type of rfactor to Array<Expr>

* Fix lint

* Improve

* Add tutorial

* Improve tutorial

* Improve tutorial

* [LANG] CommReducer

* Reorganize c_api

* Remove InitValue and Combine; refactor Functor

* Make CommReducer an Expr

* Make comm_reducer type independent

* Make CommReducerNode a Node

* Small fix

* Refine

* Refine front api; add integration testcases for min/max

* Fix python

* Refine

* Fix lint and add example

* [LANG/GPU] Cross Thread Reduction.

* Fix doxygen error

* Upgrade verilog testcase to new one

* [RUNTIME] Refactor runtime to be DLPack compatible. Enable plugin of new runtime.

* fix mac compile

* ok

* [IterVar/REFACTOR] Add types to IterVar

* [ARITH/REFACTOR] Move IntSet to include

* [REFACTOR/OP] Move Op detail to seperate folder.

* fix test