[libc] Remove *TestMain libraries and combine them with the main test libraries.

[sivachandra]

Summary

There are not tests currently which use the main test framework but not
the main function from LibcTestMain.cpp. So, this change essentially
simplifies by merging the *TestMain libraries with the main test
libraries.

[jhuber6]

Do we have facilities to merge the existing integration tests in with the hermetic tests? I believe the only difference is whether or not we get to call main directly in the test.

[sivachandra]

In D150698#4347187, @jhuber6 wrote:

Do we have facilities to merge the existing integration tests in with the hermetic tests? I believe the only difference is whether or not we get to call main directly in the test.

I am working on converting the integration tests to hermetic tests. Will start sending out patches in the coming days.

[michaelrj]

LGTM

libc/cmake/modules/LLVMLibCTestRules.cmake

set_target_properties(${fq_build_target_name}
     PROPERTIES RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
 
   add_dependencies(
     ${fq_build_target_name}
     ${fq_deps_list}
   )
 
   # LibcUnitTest should not depend on anything in LINK_LIBRARIES.
-  list(APPEND link_libraries LibcUnitTestMain LibcUnitTest)
+  list(APPEND link_libraries LibcUnitTest)
 
   target_link_libraries(${fq_build_target_name} PRIVATE ${link_libraries})
 
   if(NOT LIBC_UNITTEST_NO_RUN_POSTBUILD)
     add_custom_target(
       ${fq_target_name}
       COMMAND ${fq_build_target_name}
       COMMENT "Running unit test ${fq_target_name}"
function(add_libc_hermetic_test test_name)
   else()
     target_link_options(${fq_build_target_name} PRIVATE -nolibc -nostartfiles -nostdlib++ -static)
   endif()
   target_link_libraries(
     ${fq_build_target_name}
     PRIVATE
       ${HERMETIC_TEST_LINK_LIBRARIES}
       libc.startup.${LIBC_TARGET_OS}.crt1
-      LibcHermeticTestMain LibcHermeticTest
+      LibcHermeticTest
       # The NVIDIA 'nvlink' linker does not currently support static libraries.
       $<$<NOT:$<BOOL:${LIBC_GPU_TARGET_ARCHITECTURE_IS_NVPTX}>>:${fq_target_name}.__libc__>)
   add_dependencies(${fq_build_target_name}
                    LibcHermeticTest
                    ${fq_deps_list})
 
   # Tests on the GPU require an external loader utility to launch the kernel.
   if(TARGET libc.utils.gpu.loader)

libc/test/UnitTest/CMakeLists.txt

 set(libc_test_srcs_common
-  Test.h
-  LibcTest.cpp
   CmakeFilePath.cpp
-  LibcTest.h
+  LibcTest.cpp
+  LibcTestMain.cpp
   TestLogger.cpp
+  LibcTest.h
+  Test.h
   TestLogger.h
 )
 
 set(libc_death_test_srcs ExecuteFunction.h)
 if(${LIBC_TARGET_OS} STREQUAL "linux")
   list(APPEND libc_death_test_srcs 
        LibcDeathTestExecutors.cpp ExecuteFunctionUnix.cpp)
 endif()

 add_library(
   LibcHermeticTest
   ${library_type}
   EXCLUDE_FROM_ALL
   ${libc_test_srcs_common}
   HermeticTestUtils.cpp
 )
 
-add_library(
-  LibcUnitTestMain
-  ${library_type}
-  EXCLUDE_FROM_ALL
-  LibcTestMain.cpp
-)
-add_dependencies(LibcUnitTestMain LibcUnitTest)
-
-add_library(
-  LibcHermeticTestMain
-  ${library_type}
-  EXCLUDE_FROM_ALL
-  LibcTestMain.cpp
-)
-add_dependencies(LibcHermeticTestMain LibcHermeticTest)
-
-foreach(lib LibcUnitTest LibcUnitTestMain LibcHermeticTest LibcHermeticTestMain)
+foreach(lib LibcUnitTest LibcHermeticTest)
   target_include_directories(${lib} PUBLIC ${LIBC_SOURCE_DIR})
   target_compile_options(${lib} PRIVATE -fno-exceptions -fno-rtti)
   add_dependencies(${lib}
     libc.src.__support.c_string
     libc.src.__support.CPP.string
     libc.src.__support.CPP.string_view
     libc.src.__support.CPP.type_traits
     libc.src.__support.OSUtil.osutil
     libc.src.__support.uint128
   )
 endforeach()
 
-foreach(lib LibcHermeticTest LibcHermeticTestMain)
-  target_include_directories(${lib} PRIVATE ${LIBC_BUILD_DIR}/include)
-  target_compile_options(${lib}
-      PRIVATE ${LIBC_HERMETIC_TEST_COMPILE_OPTIONS} -ffreestanding -nostdlib -nostdlib++)
-endforeach()
+target_include_directories(LibcHermeticTest PRIVATE ${LIBC_BUILD_DIR}/include)
+target_compile_options(LibcHermeticTest
 
 add_header_library(
   string_utils
   HDRS
   StringUtils.h
   DEPENDS
     libc.src.__support.CPP.string
     libc.src.__support.CPP.type_traits