[compiler-rt] Use just built libatomic if available

[abrachet]

Summary

Use libclang_rt.atomic.so instead of the libatomic installed
on the system if it is available.

[phosek]

compiler-rt/test/lit.common.cfg.py

936

Where is this set?

938

Nit: I'd use an f-string.

[abrachet]

compiler-rt/test/lit.common.cfg.py

936

Whoops it was accidentally removed from the diff

[abrachet]

Is this ready to land @phosek?

[phosek]

LGTM

compiler-rt/test/CMakeLists.txt

 # Needed for lit support in standalone builds.
 include(AddLLVM)
 
 option(COMPILER_RT_TEST_STANDALONE_BUILD_LIBS
   "When set to ON and testing in a standalone build, test the runtime \
   libraries built by this standalone build rather than the runtime libraries \
   shipped with the compiler (used for testing). When set to OFF and testing \
   in a standalone build, test the runtime libraries shipped with the compiler \
   (used for testing). This option has no effect if the compiler and this \
   build are configured to use the same runtime library path."
   ON)
 pythonize_bool(COMPILER_RT_TEST_STANDALONE_BUILD_LIBS)
 
 pythonize_bool(LLVM_ENABLE_EXPENSIVE_CHECKS)
 
 pythonize_bool(ZLIB_FOUND)
+pythonize_bool(COMPILER_RT_BUILD_STANDALONE_LIBATOMIC)
 
 pythonize_bool(COMPILER_RT_ENABLE_INTERNAL_SYMBOLIZER)
 
 configure_compiler_rt_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.common.configured.in
   ${CMAKE_CURRENT_BINARY_DIR}/lit.common.configured)
 
 # BlocksRuntime (and most of builtins) testsuites are not yet ported to lit.

compiler-rt/test/dfsan/libatomic.c

-// RUN: %clang_dfsan -g3 -DDATA_BYTES=3 %s -fno-exceptions -latomic -o %t && %run %t
-// RUN: %clang_dfsan -g3 -DDATA_BYTES=3 -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 %s -fno-exceptions -latomic -o %t && %run %t
-// RUN: %clang_dfsan -g3 -DDATA_BYTES=32 %s -fno-exceptions -latomic -o %t && %run %t
-// RUN: %clang_dfsan -g3 -DDATA_BYTES=32 -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 %s -fno-exceptions -latomic -o %t && %run %t
+// RUN: %clang_dfsan -g3 -DDATA_BYTES=3 %s -fno-exceptions %libatomic -o %t && %run %t
+// RUN: %clang_dfsan -g3 -DDATA_BYTES=3 -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 %s -fno-exceptions %libatomic -o %t && %run %t
+// RUN: %clang_dfsan -g3 -DDATA_BYTES=32 %s -fno-exceptions %libatomic -o %t && %run %t
+// RUN: %clang_dfsan -g3 -DDATA_BYTES=32 -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 %s -fno-exceptions %libatomic -o %t && %run %t
 
 #include <assert.h>
 #include <sanitizer/dfsan_interface.h>
 #include <stdatomic.h>
 
 typedef struct __attribute((packed)) {
   uint8_t val[DATA_BYTES];
 } idata;

compiler-rt/test/lit.common.cfg.py

 
 # It is not realistically possible to account for all options that could
 # possibly be present in system and user configuration files, so disable
 # default configs for the test runs. In particular, anything hardening
 # related is likely to cause issues with sanitizer tests, because it may
 # preempt something we're looking to trap (e.g. _FORTIFY_SOURCE vs our ASAN).
 config.environment["CLANG_NO_DEFAULT_CONFIG"] = "1"
 
+if config.has_compiler_rt_libatomic:
+  base_lib = os.path.join(config.compiler_rt_libdir, "libclang_rt.atomic%s.so"
+                          % config.target_suffix)
+  if sys.platform in ['win32'] and execute_external:
+    # Don't pass dosish path separator to msys bash.exe.
+    base_lib = base_lib.replace('\\', '/')
+  config.substitutions.append(("%libatomic", base_lib + f" -Wl,-rpath,{config.compiler_rt_libdir}"))
+else:
+  config.substitutions.append(("%libatomic", "-latomic"))
+
 # Set LD_LIBRARY_PATH to pick dynamic runtime up properly.
 push_dynamic_library_lookup_path(config, config.compiler_rt_libdir)
 
 # GCC-ASan uses dynamic runtime by default.
 if config.compiler_id == "GNU":
     gcc_dir = os.path.dirname(config.clang)
     libasan_dir = os.path.join(gcc_dir, "..", "lib" + config.bits)
     push_dynamic_library_lookup_path(config, libasan_dir)

compiler-rt/test/lit.common.configured.in

 set_default("android", @ANDROID_PYBOOL@)
 set_default("android_api_level", "@ANDROID_API_LEVEL@")
 set_default("android_serial", "@ANDROID_SERIAL_FOR_TESTING@")
 set_default("android_files_to_push", [])
 set_default("have_rpc_xdr_h", @HAVE_RPC_XDR_H@)
 set_default("gwp_asan", @COMPILER_RT_HAS_GWP_ASAN_PYBOOL@)
 set_default("expensive_checks", @LLVM_ENABLE_EXPENSIVE_CHECKS_PYBOOL@)
 set_default("test_standalone_build_libs", @COMPILER_RT_TEST_STANDALONE_BUILD_LIBS_PYBOOL@)
+set_default("has_compiler_rt_libatomic", @COMPILER_RT_BUILD_STANDALONE_LIBATOMIC_PYBOOL@)
 # True iff the test suite supports ignoring the test compiler's runtime library path
 # and using `config.compiler_rt_libdir` instead. This only matters when the runtime
 # library paths differ.
 set_default("test_suite_supports_overriding_runtime_lib_path", False)
 config.available_features.add('target-is-%s' % config.target_arch)
 
 if config.enable_per_target_runtime_dir:
   set_default("target_suffix", "")

compiler-rt/test/msan/libatomic.c

-// RUN: %clang_msan -fsanitize-memory-track-origins=2 -latomic -DTEST_STORE -O0 %s -o %t && %run %t 2>&1
-// RUN: %clang_msan -fsanitize-memory-track-origins=0 -latomic -DTEST_LOAD -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK
-// RUN: %clang_msan -fsanitize-memory-track-origins=2 -latomic -DTEST_LOAD -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-SHADOW
+// RUN: %clang_msan -fsanitize-memory-track-origins=2 %libatomic -DTEST_STORE -O0 %s -o %t && %run %t 2>&1
+// RUN: %clang_msan -fsanitize-memory-track-origins=0 %libatomic -DTEST_LOAD -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK
+// RUN: %clang_msan -fsanitize-memory-track-origins=2 %libatomic -DTEST_LOAD -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-SHADOW
 
 // PPC has no libatomic
 // UNSUPPORTED: powerpc64-target-arch
 // UNSUPPORTED: powerpc64le-target-arch
 
 #include <sanitizer/msan_interface.h>
 #include <stdatomic.h>
 

compiler-rt/test/msan/libatomic_load_exceptions.cpp

-// RUN: %clangxx_msan -fexceptions -fsanitize-memory-track-origins=2 -latomic -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-SHADOW
+// RUN: %clangxx_msan -fexceptions -fsanitize-memory-track-origins=2 %libatomic -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-SHADOW
 
 // PPC has no libatomic
 // UNSUPPORTED: powerpc64-target-arch
 // UNSUPPORTED: powerpc64le-target-arch
 
 #include <sanitizer/msan_interface.h>
 #include <stdatomic.h>