[ Meson ] BCQTensor dependency is added for Android build

[EunjuYang]

• This commit add BiQGEMM path to nntrainer_inc_abs to support Android build with enable-biqgemm option.
• The path for BiQGEMM corresponds to the one in the top meson.build

Self evaluation:

Build test: [X]Passed [ ]Failed [ ]Skipped
Run test: [X]Passed [ ]Failed [ ]Skipped

[skykongkong8]

Just to be sure, this won't affect tools/package_android.sh, isn't it?

[EunjuYang]

Yes. This won't affect to the current tools/package_android.sh. This aims for the case where meson build -Dplatform=android -Denable-biqgemm=true.

[djeong20]

LGTM!
One minor suggestion: How about adding it to the tensor/meson.build for consistency?

nntrainer/nntrainer/tensor/meson.build

Lines 79 to 83 in cd17a66

	if get_option('enable-biqgemm')
	tensor_headers += 'bcq_tensor.h'
	tensor_sources += 'bcq_tensor.cpp'
	nntrainer_inc += biqgemm_inc
	endif

[EunjuYang]

LGTM! One minor suggestion: How about adding it to the tensor/meson.build for consistency?

nntrainer/nntrainer/tensor/meson.build

Lines 79 to 83 in cd17a66

	if get_option('enable-biqgemm')
	tensor_headers += 'bcq_tensor.h'
	tensor_sources += 'bcq_tensor.cpp'
	nntrainer_inc += biqgemm_inc
	endif

Following the suggestion from @djeong20, I moved the code to nntrainer/tensor/meson.build.
Since the code to check BiQGEMM folder's existence is completed at the precedent meson file, the duplicate check code is removed; simply the one line is added.

nntrainer/nntrainer/tensor/meson.build

Line 83 in 0854dde

nntrainer_inc_abs += meson.source_root() / '..' / 'BiQGEMM'

[jijoongmoon]

LGTM

[myungjoo]

meson.source_root() / '..' / 'BiQGEMM'

DO NOT HARDCODE EXTERNAL PATHS IN MESON SCRIPT!
It is completely UN-portable.

If pkgconfig or cmake is not ready with BiQGEMM,
get such information via meson_options and specify such "default paths" at meson_options.

[myungjoo]

And..

if get_option('enable-biqgemm')
  # check if BiQGEMM directory exist. otherwise, throw an error
  fs = import('fs')
  if fs.is_dir('../BiQGEMM')
    extra_defines += '-DENABLE_BIQGEMM=1'
    biqgemm_inc = include_directories('../BiQGEMM')
  else
    error ('BiQGEMM cannot be enabled without BiQGEMM library.')
  endif
endif

is completely non-sense. Other developers (e.g., nntrainer users in other departments) won't understand what's going on here.

You should try

1. get biqgemm info from pkgconfig/cmake.
2. (if 1 fails) try to load it from common path (/usr/include, /usr/include/biqgemm)
3. (if 2 fails) try to load it from user-defined path (meson_option)
4. (if 3 fails) try to load it from such hardcoded path. but specify such external hardcoded path at meson_options.txt, not in this script.

[EunjuYang]

@myungjoo, Thank you for the detailed comment and guidance :) I will make additional PR to make it feasible following your suggestion. Sincerely.