cfi: Start testing CFI in both standalone and devirtualization modes.

[pcc]

Summary

Depends on D21122

[eugenis]

LGTM w/ nit

test/cfi/CMakeLists.txt

4

In other sanitizers these config-specific directories are named in CamelCase.

test/cfi/CMakeLists.txt

+set(CFI_LIT_TEST_MODE Standalone)
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
-  ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
+  ${CMAKE_CURRENT_BINARY_DIR}/standalone/lit.site.cfg
+  )
+
+set(CFI_LIT_TEST_MODE Devirt)
+configure_lit_site_cfg(
+  ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
+  ${CMAKE_CURRENT_BINARY_DIR}/devirt/lit.site.cfg
   )
 
 set(CFI_TEST_DEPS ${SANITIZER_COMMON_LIT_TEST_DEPS})
 if(NOT COMPILER_RT_STANDALONE_BUILD)
   list(APPEND CFI_TEST_DEPS
     opt
     ubsan
     stats
if(NOT COMPILER_RT_STANDALONE_BUILD)
   if(WIN32 AND COMPILER_RT_HAS_LLD_SOURCES)
     list(APPEND CFI_TEST_DEPS
       lld
     )
   endif()
 endif()
 
 add_lit_testsuite(check-cfi "Running the cfi regression tests"
-  ${CMAKE_CURRENT_BINARY_DIR}
+  ${CMAKE_CURRENT_BINARY_DIR}/standalone
+  ${CMAKE_CURRENT_BINARY_DIR}/devirt
   DEPENDS ${CFI_TEST_DEPS})
 
 add_lit_target(check-cfi-and-supported "Running the cfi regression tests"
-  ${CMAKE_CURRENT_BINARY_DIR}
+  ${CMAKE_CURRENT_BINARY_DIR}/standalone
+  ${CMAKE_CURRENT_BINARY_DIR}/devirt
   PARAMS check_supported=1
   DEPENDS ${CFI_TEST_DEPS})
 
 set_target_properties(check-cfi PROPERTIES FOLDER "Tests")

test/cfi/lit.cfg

 import lit.formats
 import os
 
 config.name = 'cfi'
 config.suffixes = ['.c', '.cpp', '.test']
 config.test_source_root = os.path.dirname(__file__)
 
 clangxx = ' '.join([config.clang] + config.cxx_mode_flags)
 
 config.substitutions.append((r"%clang ", ' '.join([config.clang]) + ' '))
 config.substitutions.append((r"%clangxx ", clangxx + ' '))
 if config.lto_supported:
   clang_cfi = ' '.join(config.lto_launch + [config.clang] + config.lto_flags + ['-flto -fsanitize=cfi '])
+
+  if config.cfi_lit_test_mode == "Devirt":
+    config.available_features.add('devirt')
+    clang_cfi += '-fwhole-program-vtables '
+    config.substitutions.append((r"%expect_crash_unless_devirt ", ""))
+  else:
+    config.substitutions.append((r"%expect_crash_unless_devirt ", config.expect_crash))
+
   cxx = ' '.join(config.cxx_mode_flags) + ' '
   diag = '-fno-sanitize-trap=cfi -fsanitize-recover=cfi '
   non_dso = '-fvisibility=hidden '
   dso = '-fsanitize-cfi-cross-dso -fvisibility=default '
   config.substitutions.append((r"%clang_cfi ", clang_cfi + non_dso))
   config.substitutions.append((r"%clangxx_cfi ", clang_cfi + cxx + non_dso))
   config.substitutions.append((r"%clang_cfi_diag ", clang_cfi + non_dso + diag))
   config.substitutions.append((r"%clangxx_cfi_diag ", clang_cfi + cxx + non_dso + diag))
   config.substitutions.append((r"%clangxx_cfi_dso ", clang_cfi + cxx + dso))
   config.substitutions.append((r"%clangxx_cfi_dso_diag ", clang_cfi + cxx + dso + diag))
 else:
   config.unsupported = True
 
 if lit_config.params.get('check_supported', None) and config.unsupported:
   raise BaseException("Tests unsupported")

test/cfi/lit.site.cfg.in

 @LIT_SITE_CFG_IN_HEADER@
 
+config.cfi_lit_test_mode = "@CFI_LIT_TEST_MODE@"
+
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/test/lit.common.configured")
 lit_config.load_config(config, "@CMAKE_CURRENT_SOURCE_DIR@/lit.cfg")

test/cfi/overwrite.cpp

 // RUN: %clangxx_cfi -o %t1 %s
-// RUN: %expect_crash %t1 2>&1 | FileCheck --check-prefix=CFI %s
+// RUN: %expect_crash_unless_devirt %t1 2>&1 | FileCheck --check-prefix=CFI %s
 
 // RUN: %clangxx_cfi -DB32 -o %t2 %s
 // RUN: %expect_crash %t2 2>&1 | FileCheck --check-prefix=CFI %s
 
 // RUN: %clangxx_cfi -DB64 -o %t3 %s
 // RUN: %expect_crash %t3 2>&1 | FileCheck --check-prefix=CFI %s
 
 // RUN: %clangxx_cfi -DBM -o %t4 %s
int main() {
   fprintf(stderr, "1\n");
 
   // CFI-NOT: foo
   // NCFI: foo
   // CFI-DIAG: runtime error: control flow integrity check for type 'A' failed during virtual call
   // CFI-DIAG-NEXT: note: invalid vtable
   a->f();
 
-  // CFI-NOT: {{^2$}}
+  // We don't check for the absence of a 2 here because under devirtualization
+  // our virtual call may be devirtualized and we will proceed with execution
+  // rather than crashing.
+
   // NCFI: {{^2$}}
   fprintf(stderr, "2\n");
 }

test/cfi/stats.cpp

 // RUN: %clangxx_cfi -g -fsanitize-stats -o %t %s
 // RUN: env SANITIZER_STATS_PATH=%t.stats %t
 // RUN: sanstats %t.stats | FileCheck %s
 
+// FIXME: We currently emit the wrong debug info under devirtualization.
+// UNSUPPORTED: devirt
+
 struct ABase {};
 
 struct A : ABase {
   virtual void vf() {}
   void nvf() {}
 };
 
 extern "C" __attribute__((noinline)) void vcall(A *a) {

test/lit.common.cfg

 # Define CHECK-%os to check for OS-dependent output.
 config.substitutions.append( ('CHECK-%os', ("CHECK-" + config.host_os)))
 
 if config.host_os == 'Windows':
   # FIXME: This isn't quite right. Specifically, it will succeed if the program
   # does not crash but exits with a non-zero exit code. We ought to merge
   # KillTheDoctor and not --crash to make the latter more useful and remove the
   # need for this substitution.
-  config.substitutions.append( ("%expect_crash ", "not KillTheDoctor ") )
+  config.expect_crash = "not KillTheDoctor "
 else:
-  config.substitutions.append( ("%expect_crash ", "not --crash ") )
+  config.expect_crash = "not --crash "
+
+config.substitutions.append( ("%expect_crash ", config.expect_crash) )
 
 target_arch = getattr(config, 'target_arch', None)
 if target_arch:
   config.available_features.add(target_arch + '-target-arch')
   if target_arch in ['x86_64', 'i386', 'i686']:
     config.available_features.add('x86-target-arch')
 
 compiler_rt_debug = getattr(config, 'compiler_rt_debug', False)