(#12705) OpenBlas: Add arch target option

[aborzunov]

Specify library name and version: openblas/*

Now we can specify target architecture with recipe options and not rely on hardcoded in openblas cmake auto detection utilities.

closes #12705

---

• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
• I've tried at least one configuration locally with the conan-center hook activated.

[conan-center-bot]

Failure in build 4 (fc9f86bd9a24d95bd6ca56c20c7b783feabed1b3):

• openblas/0.3.15@:
  Didn't run or was cancelled before finishing

• openblas/0.3.17@:
  Didn't run or was cancelled before finishing

• openblas/0.3.20@:
  CI failed to create some packages (All logs)

  Logs for packageID 49722bfe29e816b31c8cb5aefe12da1791066439:

  [settings]
  arch=x86_64
  build_type=Release
  compiler=gcc
  compiler.libcxx=libstdc++11
  compiler.version=9
  os=Linux
  [options]
  openblas:shared=False
  

  [...]
      $ conan profile update settings.compiler.libcxx=libstdc++11 default
  
  Or edit '/home/conan/w/prod/BuildSingleReference/.conan/profiles/default' and set compiler.libcxx=libstdc++11
  
  ************************************************************************************
  
  
  
  Default settings
  	os=Linux
  	os_build=Linux
  	arch=x86_64
  	arch_build=x86_64
  	compiler=gcc
  	compiler.version=9
  	compiler.libcxx=libstdc++
  	build_type=Release
  *** You can change them in /home/conan/w/prod/BuildSingleReference/.conan/profiles/default ***
  *** Or override with -s compiler='other' -s ...s***
  
  
  Configuration:
  [settings]
  arch=x86_64
  build_type=Release
  compiler=gcc
  compiler.libcxx=libstdc++11
  compiler.version=9
  os=Linux
  [options]
  openblas:shared=False
  [build_requires]
  [env]
  [conf]
  tools.system.package_manager:mode=install
  tools.system.package_manager:sudo=True
  
  openblas/0.3.20: Forced build from source
  Installing package: openblas/0.3.20
  Requirements
      openblas/0.3.20 from local cache - Cache
  Packages
      openblas/0.3.20:49722bfe29e816b31c8cb5aefe12da1791066439 - Build
  
  Installing (downloading, building) binaries...
  [HOOK - conan-center.py] pre_source(): [IMMUTABLE SOURCES (KB-H010)] OK
  openblas/0.3.20: Configuring sources in /home/conan/w/prod/BuildSingleReference/.conan/data/openblas/0.3.20/_/_/source
  ERROR: openblas/0.3.20: Error in source() method, line 202
  	destination=self._source_subfolder
  	TypeError: get() missing 1 required positional argument: 'conanfile'
  

• openblas/0.3.13@:
  Didn't run or was cancelled before finishing

• openblas/0.3.10@:
  Didn't run or was cancelled before finishing

• openblas/0.3.12@:
  Didn't run or was cancelled before finishing

---

^{Note: To save resources, CI tries to finish as soon as an error is found. For this reason you might find that not all the references have been launched or not all the configurations for a given reference. Also, take into account that we cannot guarantee the order of execution as it depends on CI workload and workers availability.}

[uilianries]

I'm not convinced about this change. It is not a configuration to be applied as -march or -mtune to the compiler? It looks more a setting than an option. In case it's parsed directly as a compiler flags, it can be configured directly by global.conf with tools.build

[nenomius]

Agreed with @uilianries

Conan needs something like this: https://spack.readthedocs.io/en/latest/basic_usage.html#support-for-specific-microarchitectures

Let's implement it in this PR. I think you can do this in a weekend or two.

[uilianries]

@aborzunov Microarch is a complex feature listed here: conan-io/conan#847 Please, feel free to comment there your thought. So far, the best approach is customizing your settings.yml: https://docs.conan.io/en/latest/extending/custom_settings.html#adding-new-sub-settings

[aborzunov]

@uilianries

As OpenBlas documentation says, they have special option for cmake (and make) for case, when compiling for specific architecture is required. If this option is not passed to cmake, OpenBlas build scripts will ignore anything and sets compile flags as it wish. Thus, if our build server has AVX512 it will deploy broken code to clients (e.g. with haswell).

I don't quite understand why should we substitute openblas author's cmake option with settings and how should I modify recipe in this PR to deploy arch choice functionality for other conan users, if I'll be modifying local .settings.yml.

I can do something like this in _configure_cmake(self):

if self.settings.get_safe("micro_arch_target") != "None":
             cmake.definitions["TARGET"] = self.settings. micro_arch_target

And leave a comprehensive in-code comment about what is this and that user should modify local setting.yml to make it work.
This approach will hide all this functionality until user obtain broken package and dive into source code to examine it.

[uilianries]

@aborzunov Adding a custom setting in the recipe is not an option, as it's not documented.

However, you could use validate() to check if self.info.settings.arch is aligned with that option. I don't think makes sense using option value POWER10 and arch x86_64

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This pull request has been automatically closed because it has not had recent activity. Thank you for your contributions.

[elvisdukaj]

Agreed with @uilianries

Conan needs something like this: https://spack.readthedocs.io/en/latest/basic_usage.html#support-for-specific-microarchitectures

Let's implement it in this PR. I think you can do this in a weekend or two.

Agreed with @uilianries

Conan needs something like this: https://spack.readthedocs.io/en/latest/basic_usage.html#support-for-specific-microarchitectures

Let's implement it in this PR. I think you can do this in a weekend or two.

Maybe it’s worth considering creating an MR on Conan?