[Clang][Basic] Enable __has_feature(cfi)

Support `__has_feature(cfi)` to check for control flow integrity sanitizers.

Author: moorabbit

clang/include/clang/Basic/Features.def

@@ -303,6 +303,7 @@ FEATURE(is_trivially_assignable, LangOpts.CPlusPlus)
 FEATURE(is_trivially_constructible, LangOpts.CPlusPlus)
 FEATURE(is_trivially_copyable, LangOpts.CPlusPlus)
 FEATURE(is_union, LangOpts.CPlusPlus)
+FEATURE(cfi, LangOpts.Sanitize.hasOneOf(SanitizerKind::CFI))
 FEATURE(kcfi, LangOpts.Sanitize.has(SanitizerKind::KCFI))
 FEATURE(kcfi_arity, LangOpts.Sanitize.has(SanitizerKind::KCFI))
 FEATURE(modules, LangOpts.Modules)

clang/include/clang/Basic/Sanitizers.def

@@ -134,7 +134,7 @@ SANITIZER("cfi-nvcall", CFINVCall)
 SANITIZER("cfi-vcall", CFIVCall)
 SANITIZER_GROUP("cfi", CFI,
                 CFIDerivedCast | CFIICall | CFIMFCall | CFIUnrelatedCast |
-                    CFINVCall | CFIVCall)
+                    CFINVCall | CFIVCall | CFICastStrict)
 
 // Kernel Control Flow Integrity
 SANITIZER("kcfi", KCFI)

clang/test/Lexer/has_feature_cfi.c

@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -E -fsanitize=cfi-cast-strict -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E -fsanitize=cfi-derived-cast -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E -fsanitize=cfi-icall -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E -fsanitize=cfi-mfcall -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E -fsanitize=cfi-unrelated-cast -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E -fsanitize=cfi-nvcall -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E -fsanitize=cfi-vcall -o - %s | FileCheck --check-prefix=CHECK-CFISAN %s
+// RUN: %clang_cc1 -E %s -o - | FileCheck --check-prefix=CHECK-NO-CFISAN %s
+
+#if __has_feature(cfi)
+int CFISanitizerEnabled();
+#else
+int CFISanitizerDisabled();
+#endif
+
+// CHECK-CFISAN: CFISanitizerEnabled
+// CHECK-NO-CFISAN: CFISanitizerDisabled
+