Author: Vitaly Buka Date: 2022-12-04T19:10:17-08:00 New Revision: a3b48e094525ebbce95e7a9da77612adf04ae314
URL: https://github.com/llvm/llvm-project/commit/a3b48e094525ebbce95e7a9da77612adf04ae314 DIFF: https://github.com/llvm/llvm-project/commit/a3b48e094525ebbce95e7a9da77612adf04ae314.diff LOG: [NFC][CodeGen] Extract HasStrictReturn Added: Modified: clang/lib/CodeGen/CGCall.cpp Removed: ################################################################################ diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp index 836f8095f064..07606877d843 100644 --- a/clang/lib/CodeGen/CGCall.cpp +++ b/clang/lib/CodeGen/CGCall.cpp @@ -1796,6 +1796,32 @@ bool CodeGenModule::MayDropFunctionReturn(const ASTContext &Context, return ReturnType.isTriviallyCopyableType(Context); } +static bool HasStrictReturn(const CodeGenModule &Module, QualType RetTy, + const Decl *TargetDecl) { + // C++ explicitly makes returning undefined values UB. C's rule only applies + // to used values, so we never mark them noundef for now. + if (!Module.getLangOpts().CPlusPlus) + return false; + if (TargetDecl) { + if (const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(TargetDecl)) { + if (FDecl->isExternC()) + return false; + } else if (const VarDecl *VDecl = dyn_cast<VarDecl>(TargetDecl)) { + // Function pointer. + if (VDecl->isExternC()) + return false; + } + } + + // We don't want to be too aggressive with the return checking, unless + // it's explicit in the code opts or we're using an appropriate sanitizer. + // Try to respect what the programmer intended. + return Module.getCodeGenOpts().StrictReturn || + !Module.MayDropFunctionReturn(Module.getContext(), RetTy) || + Module.getLangOpts().Sanitize.has(SanitizerKind::Memory) || + Module.getLangOpts().Sanitize.has(SanitizerKind::Return); +} + void CodeGenModule::getDefaultFunctionAttributes(StringRef Name, bool HasOptnone, bool AttrOnCallSite, @@ -2325,27 +2351,9 @@ void CodeGenModule::ConstructAttributeList(StringRef Name, const ABIArgInfo &RetAI = FI.getReturnInfo(); const llvm::DataLayout &DL = getDataLayout(); - // C++ explicitly makes returning undefined values UB. C's rule only applies - // to used values, so we never mark them noundef for now. - bool HasStrictReturn = getLangOpts().CPlusPlus; - if (TargetDecl && HasStrictReturn) { - if (const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(TargetDecl)) - HasStrictReturn &= !FDecl->isExternC(); - else if (const VarDecl *VDecl = dyn_cast<VarDecl>(TargetDecl)) - // Function pointer - HasStrictReturn &= !VDecl->isExternC(); - } - - // We don't want to be too aggressive with the return checking, unless - // it's explicit in the code opts or we're using an appropriate sanitizer. - // Try to respect what the programmer intended. - HasStrictReturn &= getCodeGenOpts().StrictReturn || - !MayDropFunctionReturn(getContext(), RetTy) || - getLangOpts().Sanitize.has(SanitizerKind::Memory) || - getLangOpts().Sanitize.has(SanitizerKind::Return); - // Determine if the return type could be partially undef - if (CodeGenOpts.EnableNoundefAttrs && HasStrictReturn) { + if (CodeGenOpts.EnableNoundefAttrs && + HasStrictReturn(*this, RetTy, TargetDecl)) { if (!RetTy->isVoidType() && RetAI.getKind() != ABIArgInfo::Indirect && DetermineNoUndef(RetTy, getTypes(), DL, RetAI)) RetAttrs.addAttribute(llvm::Attribute::NoUndef); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
