[cfi] Cross-DSO CFI diagnostic mode (compiler-rt part)

* add __cfi_slowpath_diag with a 3rd parameter which is a pointer to
  the diagnostic info for the ubsan handlers.
*__cfi_check gets a 3rd parameter as well.
* unify vcall/cast/etc and icall diagnostic info format, and merge
  the handlers to have a single entry point (actually two points due
  to abort/noabort variants).
* tests

Note that this comes with a tiny overhead in the non-diag mode:
cfi_slowpath must pass 0 as the 3rd argument to cfi_check.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@258744 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 3 deletions

diff --git a/lib/ubsan/ubsan_handlers.h b/lib/ubsan/ubsan_handlers.h
index 6f309cf9a..1d4c41529 100644
--- a/lib/ubsan/ubsan_handlers.h
+++ b/lib/ubsan/ubsan_handlers.h
@@ -148,13 +148,24 @@ struct NonNullArgData {
 /// \brief Handle passing null pointer to function with nonnull attribute.
 RECOVERABLE(nonnull_arg, NonNullArgData *Data)
 
-struct CFIBadIcallData {
+/// \brief Known CFI check kinds.
+/// Keep in sync with the enum of the same name in CodeGenFunction.h
+enum CFITypeCheckKind : unsigned char {
+  CFITCK_VCall,
+  CFITCK_NVCall,
+  CFITCK_DerivedCast,
+  CFITCK_UnrelatedCast,
+  CFITCK_ICall,
+};
+
+struct CFICheckFailData {
+  CFITypeCheckKind CheckKind;
   SourceLocation Loc;
   const TypeDescriptor &Type;
 };
 
-/// \brief Handle control flow integrity failure for indirect function calls.
-RECOVERABLE(cfi_bad_icall, CFIBadIcallData *Data, ValueHandle Function)
+/// \brief Handle control flow integrity failures.
+RECOVERABLE(cfi_check_fail, CFICheckFailData *Data, ValueHandle Function)
 
 }