[Fuzzer] Avoid the unnecessary rebuild of the custom libc++

This changes the add_custom_libcxx macro to resemble the
llvm_ExternalProject_Add. The primary motivation is to avoid
unnecessary libFuzzer rebuilds that are being done on every
Ninja/Make invocation. The libc++ should be only rebuilt whenever
the libc++ source itself changes.

Differential Revision: https://reviews.llvm.org/D43213

llvm-svn: 326921

compiler-rt/cmake/Modules/AddCompilerRT.cmake

@@ -477,56 +477,97 @@ macro(add_custom_libcxx name prefix)
   foreach(flag ${LIBCXX_CFLAGS})
     set(flagstr "${flagstr} ${flag}")
   endforeach()
-  set(LIBCXX_CFLAGS ${flagstr})
+  set(LIBCXX_C_FLAGS ${flagstr})
+  set(LIBCXX_CXX_FLAGS ${flagstr})
 
   if(LIBCXX_USE_TOOLCHAIN)
     set(compiler_args -DCMAKE_C_COMPILER=${COMPILER_RT_TEST_COMPILER}
                       -DCMAKE_CXX_COMPILER=${COMPILER_RT_TEST_CXX_COMPILER})
     if(NOT COMPILER_RT_STANDALONE_BUILD)
-      set(force_deps DEPENDS clang)
+      set(toolchain_deps $<TARGET_FILE:clang>)
+      set(force_deps DEPENDS $<TARGET_FILE:clang>)
     endif()
   else()
     set(compiler_args -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
                       -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER})
   endif()
 
+  set(STAMP_DIR ${prefix}-stamps/)
+  set(BINARY_DIR ${prefix}-bins/)
+
+  add_custom_target(${name}-clear
+    COMMAND ${CMAKE_COMMAND} -E remove_directory ${BINARY_DIR}
+    COMMAND ${CMAKE_COMMAND} -E remove_directory ${STAMP_DIR}
+    COMMENT "Clobbering ${name} build and stamp directories"
+    USES_TERMINAL
+    )
+
+  add_custom_command(
+    OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${name}-clobber-stamp
+    DEPENDS ${LIBCXX_DEPS} ${toolchain_deps}
+    COMMAND ${CMAKE_COMMAND} -E touch ${BINARY_DIR}/CMakeCache.txt
+    COMMAND ${CMAKE_COMMAND} -E touch ${STAMP_DIR}/${name}-mkdir
+    COMMAND ${CMAKE_COMMAND} -E touch ${CMAKE_CURRENT_BINARY_DIR}/${name}-clobber-stamp
+    COMMENT "Clobbering bootstrap build and stamp directories"
+    )
+
+  add_custom_target(${name}-clobber
+    DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${name}-clobber-stamp)
+
   if(CMAKE_SYSROOT)
     set(sysroot_arg -DCMAKE_SYSROOT=${CMAKE_SYSROOT})
   endif()
 
   ExternalProject_Add(${name}
-    DEPENDS ${LIBCXX_DEPS}
+    DEPENDS ${name}-clobber ${LIBCXX_DEPS}
     PREFIX ${prefix}
     SOURCE_DIR ${COMPILER_RT_LIBCXX_PATH}
+    STAMP_DIR ${STAMP_DIR}
+    BINARY_DIR ${BINARY_DIR}
     CMAKE_ARGS -DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}
                ${compiler_args}
                ${sysroot_arg}
-               -DCMAKE_C_FLAGS=${LIBCXX_CFLAGS}
-               -DCMAKE_CXX_FLAGS=${LIBCXX_CFLAGS}
+               -DCMAKE_C_FLAGS=${LIBCXX_C_FLAGS}
+               -DCMAKE_CXX_FLAGS=${LIBCXX_CXX_FLAGS}
                -DCMAKE_BUILD_TYPE=Release
-               -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
+               -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
                -DLLVM_PATH=${LLVM_MAIN_SRC_DIR}
-               -DLIBCXX_STANDALONE_BUILD=On
+               -DLLVM_BINARY_DIR=${prefix}
+               -DLLVM_LIBRARY_OUTPUT_INTDIR=${prefix}/lib
+               -DLIBCXX_STANDALONE_BUILD=ON
                ${LIBCXX_CMAKE_ARGS}
-    STEP_TARGETS configure build install
-    LOG_BUILD 1
-    LOG_CONFIGURE 1
-    LOG_INSTALL 1
+    INSTALL_COMMAND ""
+    STEP_TARGETS configure build
+    BUILD_ALWAYS 1
+    USES_TERMINAL_CONFIGURE 1
+    USES_TERMINAL_BUILD 1
+    USES_TERMINAL_INSTALL 1
     EXCLUDE_FROM_ALL TRUE
     )
 
-  ExternalProject_Add_Step(${name} force-reconfigure
-    DEPENDERS configure
-    ALWAYS 1
-    )
+  if (CMAKE_GENERATOR MATCHES "Make")
+    set(run_clean "$(MAKE)" "-C" "${BINARY_DIR}" "clean")
+  else()
+    set(run_clean ${CMAKE_COMMAND} --build ${BINARY_DIR} --target clean
+                                   --config "$<CONFIGURATION>")
+  endif()
 
-  ExternalProject_Add_Step(${name} clobber
-    COMMAND ${CMAKE_COMMAND} -E remove_directory <BINARY_DIR>
-    COMMAND ${CMAKE_COMMAND} -E make_directory <BINARY_DIR>
-    COMMENT "Clobberring ${name} build directory..."
-    DEPENDERS configure
+  ExternalProject_Add_Step(${name} clean
+    COMMAND ${run_clean}
+    COMMENT "Cleaning ${name}..."
+    DEPENDEES configure
     ${force_deps}
+    WORKING_DIRECTORY ${BINARY_DIR}
+    EXCLUDE_FROM_MAIN 1
+    USES_TERMINAL 1
     )
+  ExternalProject_Add_StepTargets(${name} clean)
+
+  if(LIBCXX_USE_TOOLCHAIN)
+    add_dependencies(${name}-clean ${name}-clobber)
+    set_target_properties(${name}-clean PROPERTIES
+      SOURCES ${CMAKE_CURRENT_BINARY_DIR}/${name}-clobber-stamp)
+  endif()
 endmacro()
 
 function(rt_externalize_debuginfo name)

compiler-rt/lib/fuzzer/CMakeLists.txt

@@ -86,7 +86,7 @@ if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux" AND COMPILER_RT_LIBCXX_PATH)
     set(cxx_${arch}_merge_dir "${CMAKE_CURRENT_BINARY_DIR}/cxx_${arch}_merge.dir")
     file(MAKE_DIRECTORY ${cxx_${arch}_merge_dir})
     add_custom_command(TARGET clang_rt.${name}-${arch} POST_BUILD
-      COMMAND ${CMAKE_LINKER} --whole-archive "$<TARGET_LINKER_FILE:clang_rt.${name}-${arch}>" --no-whole-archive ${dir}/src/libcxx_fuzzer_${arch}-build/lib/libc++.a -r -o ${name}.o
+      COMMAND ${CMAKE_LINKER} --whole-archive "$<TARGET_LINKER_FILE:clang_rt.${name}-${arch}>" --no-whole-archive ${dir}/lib/libc++.a -r -o ${name}.o
       COMMAND ${CMAKE_OBJCOPY} --localize-hidden ${name}.o
       COMMAND ${CMAKE_COMMAND} -E remove "$<TARGET_LINKER_FILE:clang_rt.${name}-${arch}>"
       COMMAND ${CMAKE_AR} qcs "$<TARGET_LINKER_FILE:clang_rt.${name}-${arch}>" ${name}.o
@@ -104,9 +104,9 @@ if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux" AND COMPILER_RT_LIBCXX_PATH)
              -fvisibility=hidden
       CMAKE_ARGS -DLIBCXX_ENABLE_EXCEPTIONS=OFF
                  -DLIBCXX_CXX_ABI=none)
-    target_compile_options(RTfuzzer.${arch} PRIVATE -isystem ${COMPILER_RT_LIBCXX_PATH}/include)
+    target_compile_options(RTfuzzer.${arch} PRIVATE -isystem ${LIBCXX_${arch}_PREFIX}/include/c++/v1)
     add_dependencies(RTfuzzer.${arch} libcxx_fuzzer_${arch}-build)
-    target_compile_options(RTfuzzer_main.${arch} PRIVATE -isystem ${COMPILER_RT_LIBCXX_PATH}/include)
+    target_compile_options(RTfuzzer_main.${arch} PRIVATE -isystem ${LIBCXX_${arch}_PREFIX}/include/c++/v1)
     add_dependencies(RTfuzzer_main.${arch} libcxx_fuzzer_${arch}-build)
     partially_link_libcxx(fuzzer_no_main ${LIBCXX_${arch}_PREFIX} ${arch})
     partially_link_libcxx(fuzzer ${LIBCXX_${arch}_PREFIX} ${arch})

compiler-rt/lib/fuzzer/tests/CMakeLists.txt

@@ -40,7 +40,7 @@ foreach(arch ${FUZZER_SUPPORTED_ARCH})
   if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux" AND COMPILER_RT_LIBCXX_PATH)
     set(LIBFUZZER_TEST_RUNTIME_DEPS libcxx_fuzzer_${arch}-build)
     set(LIBFUZZER_TEST_RUNTIME_CFLAGS -isystem ${COMPILER_RT_LIBCXX_PATH}/include)
-    set(LIBFUZZER_TEST_RUNTIME_LINK_FLAGS ${LIBCXX_${arch}_PREFIX}/src/libcxx_fuzzer_${arch}-build/lib/libc++.a)
+    set(LIBFUZZER_TEST_RUNTIME_LINK_FLAGS ${LIBCXX_${arch}_PREFIX}/lib/libc++.a)
   endif()
 
   set(FuzzerTestObjects)

compiler-rt/lib/msan/tests/CMakeLists.txt

@@ -109,7 +109,7 @@ macro(add_msan_tests_for_arch arch kind cflags)
                    DEPS ${MSAN_INST_LOADABLE_OBJECTS})
 
   set(MSAN_TEST_OBJECTS ${MSAN_INST_TEST_OBJECTS} ${MSAN_INST_GTEST})
-  set(MSAN_TEST_DEPS ${MSAN_TEST_OBJECTS} libcxx_msan_${arch}-install
+  set(MSAN_TEST_DEPS ${MSAN_TEST_OBJECTS} libcxx_msan_${arch}-build
                      ${MSAN_LOADABLE_SO})
   if(NOT COMPILER_RT_STANDALONE_BUILD)
     list(APPEND MSAN_TEST_DEPS msan)

compiler-rt/lib/tsan/CMakeLists.txt

@@ -214,7 +214,7 @@ if(COMPILER_RT_LIBCXX_PATH AND
       DEPS ${TSAN_RUNTIME_LIBRARIES}
       CFLAGS ${TARGET_CFLAGS} -fsanitize=thread
       USE_TOOLCHAIN)
-    list(APPEND libcxx_tsan_deps libcxx_tsan_${arch}-install)
+    list(APPEND libcxx_tsan_deps libcxx_tsan_${arch}-build)
   endforeach()
 
   add_custom_target(libcxx_tsan DEPENDS ${libcxx_tsan_deps})

compiler-rt/test/fuzzer/lit.cfg

@@ -7,8 +7,6 @@ config.test_format = lit.formats.ShTest(True)
 config.suffixes = ['.test']
 config.test_source_root = os.path.dirname(__file__)
 
-config.environment['LD_LIBRARY_PATH'] = config.llvm_library_dir
-
 # Choose between lit's internal shell pipeline runner and a real shell.  If
 # LIT_USE_INTERNAL_SHELL is in the environment, we use that as an override.
 use_lit_shell = os.environ.get("LIT_USE_INTERNAL_SHELL")
@@ -54,9 +52,9 @@ config.substitutions.append(('%libfuzzer_src', libfuzzer_src_root))
 def generate_compiler_cmd(is_cpp=True, fuzzer_enabled=True):
   compiler_cmd = config.c_compiler
   if config.clang and config.stdlib == 'libc++':
-    link_cmd = '-stdlib=libc++'
+    link_cmd = '-stdlib=libc++ -Wl,-rpath=%s' % config.llvm_library_dir
   elif config.clang and config.stdlib == 'static-libc++':
-    link_cmd = '-stdlib=libc++ -lc++abi -static-libstdc++'
+    link_cmd = '-stdlib=libc++ -lc++abi -static-libstdc++ -Wl,-rpath=%s' % config.llvm_library_dir
   else:
     link_cmd = '-lc++' if any(x in config.target_triple for x in ('darwin', 'freebsd')) else '-lstdc++'
   std_cmd = '--driver-mode=g++ -std=c++11' if is_cpp else ''

compiler-rt/test/tsan/lit.cfg

@@ -56,7 +56,7 @@ clang_tsan_cxxflags = config.cxx_mode_flags + clang_tsan_cflags + ["-std=c++11"]
 if config.has_libcxx and config.host_os != 'Darwin':
   # FIXME: Dehardcode this path somehow.
   libcxx_path = os.path.join(config.compiler_rt_obj_root, "lib",
-                             "tsan", "libcxx_tsan_" + config.target_arch)
+                             "tsan", "libcxx_tsan_%s" % config.target_arch)
   libcxx_incdir = os.path.join(libcxx_path, "include", "c++", "v1")
   libcxx_libdir = os.path.join(libcxx_path, "lib")
   libcxx_so = os.path.join(libcxx_libdir, "libc++.so")