* add stack op frontend

* concate moved

* topi stack added

* stack added

* fix stack bugs and tested

* conv2d alterlayout udpated for relay

* fix pylint

* fix cmake warnings

* cmake warnings fixed

* bug fix

* trigger ci

* [RELAY][OP] Proposal

* Fix

* Fix test

* use LLVM linker

* error message improved in case of filenotfound

* linting error fixed

add test

remove dead code

stash

do it

add more test

* fix docments

* delete e

* Add slice axis op in mxnet converter

* Fix lint

* Add batch_dot and cpu schedule

* Add relay support for batch_dot

* Rename batch_dot to batch_matmul

* nits

* Add missing file

* Put batch_matmul and dense x86 schedule in separate files

* Fix pylint

* Remove unused import

* Add cuda schedule for batch_matmul

* Add test case with larger batch size

* Add batch_matmul in api doc

* Fix quantize pass rounding error

* Fix pylint and minor change

* bug fix

* Defined a common base class for TensorComputeOp and ComputeOp

* Made changes requested by @ZihengJiang

* added a testcase to assert that `tensorize` does not have any effect on TensorComputeOp ops.

* [DOCKER] Make all install .sh scripts directly executable.

* [DOCKER] Use curl -L consistently.

Make the use of the curl -L option in docker build scripts consistent.

* [DOCKER] Drop use of --force-yes

The --force-yes option is generally not recommend, it can leave
systems in an undefined state.  The use of --allow-* options is
preferred.  In this particular case the --force-yes option appears to
serve no purpose.  Dropping it.

* [DOCKER] Drop superflous repeated apt-get update.

The "apt-get update && apt-get install" idiom is necessary and
specific to Dockerfile.  In shell the repeated apt-get update is
superflous.  Drop the duplicates.

* [DOCKER] Robustness -e -u -o pipefail

The install scripts used to construct docker environments do not, in
general, propagate errors.  Some of the scripts use adhoc &&
directives to chain together short sequences of commands but there are
numerous failure modes which are silently ignored.  This patch puts in
place some consistent, basic, shell error trapping across all of the
install scripts.

Note this is a step forward towards more robust scripts but it is not
a complete solution.

* [DOCKER] Shallow clone.

Use shallow clone to reduce bandwidth requirements of repeated docker
(re)-builds.

* [DOCKER] Use clone --branch rather than clone then checkout

Use the git clone --branch idiom rather than git clone && git
checkout.  This paves the way for using --depth=1

* [SCRIPT] Refactor grep for multiple patterns

Tidy up the use of grep.  Use -E rather than run multiple grep
instances.

* [SCRIPT] Refactor grep use in pipeline.

Prefer to use stdin redirection rather than create a pipeline.

* [SCRIPT] Refactor placement and cleanup of temporary files.

Place temporary files in the conventional /tmp location. Avoid
poisoning file name space by using $$. Ensure the temporary files get
cleaned up, even when the script fails / exits early.

* [SCRIPT] Improve robustness of task_lint.sh error handling.

Ensure script failures are caught and propagated.  Rather than trying
to explicitly catch and propagate failures with explicit "|| exit"
annotations, use the "set -e" idom from docker/install scripts and
have the shell catch and propagate errors in the general case and
special case the grep instances where non zero exit is permitted and
should be ignored.

* do

* address comment

* [DOCKER] Switch from yes|apt-get to apt-get -y

The yes | apt-get idom guarantees that the 'yes' process always exists
with exit code 141 (pipe broken).  This is fine while the script
generally ignores failures but won't work when the script behaviour is
tightened to robustly catch errors.

* [DOCKER] Turn down the wget/curl volume

* added relay quick start

* added relay/using_external_lib.py

* update using_external_lib

* Update using_external_lib.py

* update tvm/make/config.mk -> cmake/config.cmake

* Fixed: result mismatched when lowering relay with cudnn support at opt level 2

* setting opt_level=2 and out_channels=16 for consistency of original tutorial

* Fixed some typos

* move layout.h & layout.cc from relay to tvm

* change ConvertLayout in relay to bijectiveLayout->Forward/backward

* add first test case

* add LayoutAxis

* add LayoutAxis struct and compiles

* simplify BijectiveLayout rule consturct

* polish func name for Layout, move impl to .cc, remove Layout::defined(), add defined() checker

* partially add layout py support

* add layout test cases

* add doc for tvm.layout & tvm.bijective_layout

* fix lint

* fix lint

* fix layout name generation bug

* fix layout typo

* address comments and add topi.layout_transform

* layout.h->data_layout.h, test_lang_layout.py->test_lang_data_layout.py

* check in

* lint

* cleanup

* Update util.py

tshape.strip('()[]').split(',') will make a list ['1001',''] but the empty one isn't needed.

Recent pylint introduced support for the useless-return diagnostic.
This patch remove the useless returns.