================ @@ -21,16 +21,67 @@ #include "clang/StaticAnalyzer/Core/PathSensitive/CallDescription.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" +#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h" #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicExtent.h" +#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h" using namespace clang; using namespace ento; namespace { +QualType getOverflowBuiltinResultType(const CallEvent &Call) { + assert(Call.getNumArgs() == 3); + + return Call.getArgExpr(2)->getType()->getPointeeType(); +} + +QualType getOverflowBuiltinResultType(const CallEvent &Call, CheckerContext &C, + unsigned BI) { + assert(Call.getNumArgs() == 3); + + ASTContext &Ast = C.getASTContext(); + + switch (BI) { + case Builtin::BI__builtin_smul_overflow: + case Builtin::BI__builtin_ssub_overflow: + case Builtin::BI__builtin_sadd_overflow: + return Ast.IntTy; + case Builtin::BI__builtin_smull_overflow: + case Builtin::BI__builtin_ssubl_overflow: + case Builtin::BI__builtin_saddl_overflow: + return Ast.LongTy; + case Builtin::BI__builtin_smulll_overflow: + case Builtin::BI__builtin_ssubll_overflow: + case Builtin::BI__builtin_saddll_overflow: + return Ast.LongLongTy; + case Builtin::BI__builtin_umul_overflow: + case Builtin::BI__builtin_usub_overflow: + case Builtin::BI__builtin_uadd_overflow: + return Ast.UnsignedIntTy; + case Builtin::BI__builtin_umull_overflow: + case Builtin::BI__builtin_usubl_overflow: + case Builtin::BI__builtin_uaddl_overflow: + return Ast.UnsignedLongTy; + case Builtin::BI__builtin_umulll_overflow: + case Builtin::BI__builtin_usubll_overflow: + case Builtin::BI__builtin_uaddll_overflow: + return Ast.UnsignedLongLongTy; + case Builtin::BI__builtin_mul_overflow: + case Builtin::BI__builtin_sub_overflow: + case Builtin::BI__builtin_add_overflow: + return getOverflowBuiltinResultType(Call); + default: + assert(false && "Unknown overflow builtin"); ---------------- steakhal wrote:
When using asserts, one should also consider the path when they are violated. For example in `NDEBUG`, they disappear, and we end up with UB by not returning a value from a function. In such cases returning a non-harmful value is usually better than having an immediate UB. ```suggestion assert(false && "Unknown overflow builtin"); return Ast.IntTy; ``` https://github.com/llvm/llvm-project/pull/102602 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits