[libcxxabi, libunwind] [test] Place output from tests under a 'test' subdir

[mstorsjo]

Summary

Previously, all the output from the tests were placed directly in
the build directory. The tests produce a couple directories named
__config_{exec,cache,src}__ which are easy to distinguish, and
the output from the individual tests were placed directly in a
directory named Output.

This is the same change as
736c6e246f5398331d83edd204a846cc967ad5c6, but for the libcxxabi
and libunwind test suites.

[phosek]

LGTM

libcxxabi/test/configs/cmake-bridge.cfg.in

 site.addsitedir(os.path.join('@LIBCXXABI_SOURCE_DIR@', 'test'))
 import libcxx.test.format
 
 # Basic configuration of the test suite
 config.name = os.path.basename('@LIBCXXABI_TEST_CONFIG@')
 config.test_source_root = os.path.join('@LIBCXXABI_SOURCE_DIR@', 'test')
 config.test_format = libcxx.test.format.CxxStandardLibraryTest()
 config.recursiveExpansionLimit = 10
-config.test_exec_root = '@CMAKE_BINARY_DIR@'
+config.test_exec_root = os.path.join('@CMAKE_BINARY_DIR@', 'test')
 
 # TODO: This is a non-standard Lit attribute and we should have another way of accessing this.
 config.host_triple = '@LLVM_HOST_TRIPLE@'
 
 config.substitutions.append(('%{cxx}', '@CMAKE_CXX_COMPILER@'))
 config.substitutions.append(('%{libcxx}', '@LIBCXXABI_LIBCXX_PATH@'))
 config.substitutions.append(('%{include}', '@LIBCXXABI_SOURCE_DIR@/include'))
 config.substitutions.append(('%{cxx-include}', '@LIBCXXABI_HEADER_DIR@/include/c++/v1'))
 config.substitutions.append(('%{cxx-target-include}', '@LIBCXXABI_HEADER_DIR@/include/%{triple}/c++/v1'))
 config.substitutions.append(('%{lib}', '@LIBCXXABI_LIBRARY_DIR@'))
 config.substitutions.append(('%{executor}', '@LIBCXXABI_EXECUTOR@'))
 
 if @LIBCXXABI_USE_LLVM_UNWINDER@:
     config.substitutions.append(('%{maybe-include-libunwind}', '-I "@LIBCXXABI_LIBUNWIND_INCLUDES_INTERNAL@"'))
 else:
     config.substitutions.append(('%{maybe-include-libunwind}', ''))

libunwind/test/configs/cmake-bridge.cfg.in

 site.addsitedir(os.path.join('@LIBUNWIND_LIBCXX_PATH@', 'utils'))
 import libcxx.test.format
 
 # Basic configuration of the test suite
 config.name = os.path.basename('@LIBUNWIND_TEST_CONFIG@')
 config.test_source_root = os.path.join('@LIBUNWIND_SOURCE_DIR@', 'test')
 config.test_format = libcxx.test.format.CxxStandardLibraryTest()
 config.recursiveExpansionLimit = 10
-config.test_exec_root = '@CMAKE_BINARY_DIR@'
+config.test_exec_root = os.path.join('@CMAKE_BINARY_DIR@', 'test')
 
 # Add a few features that are common to all the configurations
 if @LIBUNWIND_USES_ARM_EHABI@:
     config.available_features.add('libunwind-arm-ehabi')
 if not @LIBUNWIND_ENABLE_THREADS@:
     config.available_features.add('libunwind-no-threads')
 
 # Add substitutions for bootstrapping the test suite configuration
 import shlex
 config.substitutions.append(('%{cxx}', shlex.quote('@CMAKE_CXX_COMPILER@')))
 config.substitutions.append(('%{executor}', '@LIBUNWIND_EXECUTOR@'))
 config.substitutions.append(('%{include}', '@LIBUNWIND_SOURCE_DIR@/include'))
 config.substitutions.append(('%{lib}', '@LIBUNWIND_LIBRARY_DIR@'))