[ubsan] Treat ObjC's BOOL as if its range is always {0, 1}
On some Apple platforms, the ObjC BOOL type is defined as a signed char.
When performing instrumentation for -fsanitize=bool, we'd like to treat
the range of BOOL like it's always {0, 1}. While we can't change clang's
IRGen for char-backed BOOL's due to ABI compatibility concerns, we can
teach ubsan to catch potential abuses of this type.
rdar://problem/29502773
Differential Revision: https://reviews.llvm.org/D27607
llvm-svn: 289290
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index bd21a86..dc147a1 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -24,6 +24,7 @@
#include "clang/AST/ASTContext.h"
#include "clang/AST/Attr.h"
#include "clang/AST/DeclObjC.h"
+#include "clang/AST/NSAPI.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/StringExtras.h"
@@ -1219,11 +1220,10 @@
static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
llvm::APInt &Min, llvm::APInt &End,
- bool StrictEnums) {
+ bool StrictEnums, bool IsBool) {
const EnumType *ET = Ty->getAs<EnumType>();
bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
ET && !ET->getDecl()->isFixed();
- bool IsBool = hasBooleanRepresentation(Ty);
if (!IsBool && !IsRegularCPlusPlusEnum)
return false;
@@ -1253,8 +1253,8 @@
llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
llvm::APInt Min, End;
- if (!getRangeForType(*this, Ty, Min, End,
- CGM.getCodeGenOpts().StrictEnums))
+ if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
+ hasBooleanRepresentation(Ty)))
return nullptr;
llvm::MDBuilder MDHelper(getLLVMContext());
@@ -1313,14 +1313,15 @@
false /*ConvertTypeToTag*/);
}
- bool NeedsBoolCheck =
- SanOpts.has(SanitizerKind::Bool) && hasBooleanRepresentation(Ty);
+ bool IsBool = hasBooleanRepresentation(Ty) ||
+ NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
+ bool NeedsBoolCheck = SanOpts.has(SanitizerKind::Bool) && IsBool;
bool NeedsEnumCheck =
SanOpts.has(SanitizerKind::Enum) && Ty->getAs<EnumType>();
if (NeedsBoolCheck || NeedsEnumCheck) {
SanitizerScope SanScope(this);
llvm::APInt Min, End;
- if (getRangeForType(*this, Ty, Min, End, true)) {
+ if (getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool)) {
--End;
llvm::Value *Check;
if (!Min)