[SystemZ][z/OS] Add custom config file for libc++/abi testing

[muiez]

Summary

This initial change adds the z/OS custom configuration file for libc++/abi which adds the appropriate compiler and linker flags for LIT testing.

[muiez]

The motivation of this patch is to incrementally integrate a libc++ CI for z/OS.

libcxx/test/configs/ibm-zos-libc++-shared.cfg.in

23–24

The libraries libc++_a & libc++_exception are generated in the following patches: https://reviews.llvm.org/D118503 & https://reviews.llvm.org/D118620. Their comments have been addressed and are awaiting review.

The libc++abixl & libunwind libraries will be provided with the OS.

[zibi]

Looking good, I wonder if we can incorporating a small change to set PATH, see inline comment in ibm-zos-libc++-shared.cfg.in.

libcxx/CMakeLists.txt

269

Consider moving this to Configure System section were various output directories are being set, for example: LIBCXX_LIBRARY_DIR.

libcxx/test/configs/ibm-zos-libc++-shared.cfg.in

34–35

[muiez]

Address comments.

[zibi]

LGTM, thank you.

[muiez]

kickoff CI

[muiez]

Rebase with latest main.

[muiez]

@libc++ The CI is green, can I get a review please? Thanks

[muiez]

Ping, can I get a review? @libcxx

[Mordante]

Sorry it seems I overlooked this patch.
Can you rebase it?
Next time feel free to ping us at Discord, there we tend to miss less messages.
I really like @ldionne to have a look, I'll ping him on Discord.

[muiez]

Rebase

[muiez]

@ldionne May I get a review please? Thanks

[muiez]

Ping :)

libcxx/CMakeLists.txt

 option(LIBCXXABI_USE_LLVM_UNWINDER "Build and use the LLVM unwinder." OFF)
 
 # Target options --------------------------------------------------------------
 option(LIBCXX_BUILD_32_BITS "Build 32 bit multilib libc++. This option is not supported anymore when building the runtimes. Please specify a full triple instead." ${LLVM_BUILD_32_BITS})
 if (LIBCXX_BUILD_32_BITS)
   message(FATAL_ERROR "LIBCXX_BUILD_32_BITS is not supported anymore when building the runtimes, please specify a full triple instead.")
 endif()
 
 # TODO: Remove this after branching for LLVM 15
 if(LIBCXX_SYSROOT OR LIBCXX_TARGET_TRIPLE OR LIBCXX_GCC_TOOLCHAIN)
   message(WARNING "LIBCXX_SYSROOT, LIBCXX_TARGET_TRIPLE and LIBCXX_GCC_TOOLCHAIN are not supported anymore, please use the native CMake equivalents instead")
 endif()
 
 # Feature options -------------------------------------------------------------
 option(LIBCXX_ENABLE_EXCEPTIONS "Use exceptions." ON)
 option(LIBCXX_ENABLE_RTTI "Use run time type information." ON)
 option(LIBCXX_ENABLE_THREADS "Build libc++ with support for threads." ON)

 endif()
 
 file(MAKE_DIRECTORY "${LIBCXX_BINARY_INCLUDE_DIR}")
 
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBCXX_LIBRARY_DIR})
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIBCXX_LIBRARY_DIR})
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LIBCXX_LIBRARY_DIR})
 
+if (ZOS)
+  set(LIBCXX_DATASET_PREFIX "" CACHE STRING "Use the dataset prefix.")
+endif()
+
 # Declare libc++ configuration variables.
 # They are intended for use as follows:
 # LIBCXX_CXX_FLAGS: General flags for both the compiler and linker.
 # LIBCXX_COMPILE_FLAGS: Compile only flags.
 # LIBCXX_LINK_FLAGS: Linker only flags.
 # LIBCXX_LIBRARIES: libraries libc++ is linked to.
 set(LIBCXX_COMPILE_FLAGS "")
 set(LIBCXX_LINK_FLAGS "")

libcxx/test/configs/ibm-zos-libc++-shared.cfg.in

+# This testing configuration handles running the libc++ tests on
+# z/OS using a shared library.
+
+import os, site
+
+lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
+
+config.substitutions.append(('%{flags}', ''))
+
+compile_flags = '-nostdinc++ -I %{include} -I %{libcxx}/test/support'
+if os.getenv('ZOS_LIBCXX_TEST_ASCII') == '1':
+    # Testing ASCII
+    compile_flags += ' -fzos-le-char-mode=ascii'
+else:
+    # Testing EBCDIC
+    compile_flags += ' -D_LIBCPP_HAS_NO_UNICODE'
+    config.available_features.add('zos-ebcdic')
+
+config.substitutions.append(('%{compile_flags}', compile_flags))
+
+config.substitutions.append(('%{link_flags}',
+    '-nostdlib++ -L %{install}/lib -L %{install}/libcxx/lib -lc++ -lc++_a \
+    -lc++_exception -lc++abi -lc++abixl -lunwind'))
+
+dataset_prefix = '@LIBCXX_DATASET_PREFIX@'
+if dataset_prefix is None:
+    raise ValueError('No dataset prefix has been provided.')
+
+steplib = dataset_prefix + '.SCEERUN2'
+if os.getenv('STEPLIB',''):
+    steplib += ":" + os.environ['STEPLIB']
+
+path = os.environ['PATH']
+
+config.substitutions.append(('%{exec}',
+    '%{{executor}} --execdir %T --env _BPXK_AUTOCVT=ON STEPLIB={0} PATH={1} -- '.format(steplib,path)))
+
+site.addsitedir(os.path.join('@LIBCXX_SOURCE_DIR@', 'utils'))
+import libcxx.test.params, libcxx.test.newconfig
+libcxx.test.newconfig.configure(
+    libcxx.test.params.DEFAULT_PARAMETERS,
+    libcxx.test.features.DEFAULT_FEATURES,
+    config,
+    lit_config
+)

libcxxabi/test/configs/ibm-zos-libc++abi-shared.cfg.in

+# Testing configuration for libc++abi on z/OS.
+
+import os, site
+
+lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
+
+config.substitutions.append(('%{flags}',''))
+
+compile_flags = '-nostdinc++ -I %{include} -I %{cxx-include} -I %{cxx-target-include} \
+    -D_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS \
+    -I %{libcxx}/test/support -I %{libcxx}/src -I %{libcxx}/include/c++build'
+
+if os.getenv('ZOS_LIBCXX_TEST_ASCII') == '1':
+    # Testing ASCII
+    compile_flags += ' -fzos-le-char-mode=ascii'
+else:
+    # Testing EBCDIC
+    compile_flags += ' -D_LIBCPP_HAS_NO_UNICODE'
+    config.available_features.add('zos-ebcdic')
+
+config.substitutions.append(('%{compile_flags}', compile_flags))
+
+config.substitutions.append(('%{link_flags}',
+    '-nostdlib++ -L %{install}/lib -L %{install}/libcxx/lib -lc++ -lc++_a \
+    -lc++_exception -lc++abi -lc++abixl -lunwind'))
+
+dataset_prefix = '@LIBCXX_DATASET_PREFIX@'
+if dataset_prefix is None:
+    raise ValueError('No dataset prefix has been provided.')
+
+steplib = dataset_prefix + '.SCEERUN2'
+if os.getenv('STEPLIB',''):
+    steplib += ":" + os.environ['STEPLIB']
+
+config.substitutions.append(('%{exec}',
+    '%{{executor}} --execdir %T --env _BPXK_AUTOCVT=ON STEPLIB={0} -- '.format(steplib)))
+
+site.addsitedir(os.path.join('@LIBCXXABI_LIBCXX_PATH@', 'utils'))
+import libcxx.test.params, libcxx.test.newconfig, libcxx.test.newconfig
+libcxx.test.newconfig.configure(
+    libcxx.test.params.DEFAULT_PARAMETERS,
+    libcxx.test.features.DEFAULT_FEATURES,
+    config,
+    lit_config
+)