From fb8d02b179732b17897f1d4024583949a56b0bb5 Mon Sep 17 00:00:00 2001 From: Alp Toker Date: Thu, 5 Jun 2014 22:10:59 +0000 Subject: Implement -Wframe-larger-than backend diagnostic Add driver and frontend support for the GCC -Wframe-larger-than=bytes warning. This is the first GCC-compatible backend diagnostic built around LLVM's reporting feature. This commit adds infrastructure to perform reverse lookup from mangled names emitted after LLVM IR generation. We use that to resolve precise locations and originating AST functions, lambdas or block declarations to produce seamless codegen-guided diagnostics. An associated change, StringMap now maintains unique mangled name strings instead of allocating copies. This is a net memory saving in C++ and a small hit for C where we no longer reuse IdentifierInfo storage, pending further optimisation. llvm-svn: 210293 --- clang/lib/CodeGen/CodeGenModule.cpp | 70 ++++++++++++++++++++----------------- 1 file changed, 37 insertions(+), 33 deletions(-) (limited to 'clang/lib/CodeGen/CodeGenModule.cpp') diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index ac89ce6..9cb84f8 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -498,47 +498,40 @@ void CodeGenModule::setTLSMode(llvm::GlobalVariable *GV, } StringRef CodeGenModule::getMangledName(GlobalDecl GD) { - const auto *ND = cast(GD.getDecl()); - - StringRef &Str = MangledDeclNames[GD.getCanonicalDecl()]; - if (!Str.empty()) - return Str; + StringRef &FoundStr = MangledDeclNames[GD.getCanonicalDecl()]; + if (!FoundStr.empty()) + return FoundStr; - if (!getCXXABI().getMangleContext().shouldMangleDeclName(ND)) { + const auto *ND = cast(GD.getDecl()); + SmallString<256> Buffer; + StringRef Str; + if (getCXXABI().getMangleContext().shouldMangleDeclName(ND)) { + llvm::raw_svector_ostream Out(Buffer); + if (const auto *D = dyn_cast(ND)) + getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out); + else if (const auto *D = dyn_cast(ND)) + getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out); + else + getCXXABI().getMangleContext().mangleName(ND, Out); + Str = Out.str(); + } else { IdentifierInfo *II = ND->getIdentifier(); assert(II && "Attempt to mangle unnamed decl."); - Str = II->getName(); - return Str; } - - SmallString<256> Buffer; - llvm::raw_svector_ostream Out(Buffer); - if (const auto *D = dyn_cast(ND)) - getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out); - else if (const auto *D = dyn_cast(ND)) - getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out); - else - getCXXABI().getMangleContext().mangleName(ND, Out); - // Allocate space for the mangled name. - Out.flush(); - size_t Length = Buffer.size(); - char *Name = MangledNamesAllocator.Allocate(Length); - std::copy(Buffer.begin(), Buffer.end(), Name); - - Str = StringRef(Name, Length); - - return Str; + auto &Mangled = Manglings.GetOrCreateValue(Str); + Mangled.second = GD; + return FoundStr = Mangled.first(); } -std::string CodeGenModule::getBlockMangledName(GlobalDecl GD, - const BlockDecl *BD) { +StringRef CodeGenModule::getBlockMangledName(GlobalDecl GD, + const BlockDecl *BD) { MangleContext &MangleCtx = getCXXABI().getMangleContext(); const Decl *D = GD.getDecl(); - std::string Buffer; - llvm::raw_string_ostream Out(Buffer); + SmallString<256> Buffer; + llvm::raw_svector_ostream Out(Buffer); if (!D) MangleCtx.mangleGlobalBlock(BD, dyn_cast_or_null(initializedGlobalDecl.getDecl()), Out); @@ -549,7 +542,9 @@ std::string CodeGenModule::getBlockMangledName(GlobalDecl GD, else MangleCtx.mangleBlock(cast(D), BD, Out); - return Out.str(); + auto &Mangled = Manglings.GetOrCreateValue(Out.str()); + Mangled.second = BD; + return Mangled.first(); } llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) { @@ -1462,7 +1457,7 @@ CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName, // This is the first use or definition of a mangled name. If there is a // deferred decl with this name, remember that we need to emit it at the end // of the file. - llvm::StringMap::iterator DDI = DeferredDecls.find(MangledName); + auto DDI = DeferredDecls.find(MangledName); if (DDI != DeferredDecls.end()) { // Move the potentially referenced deferred decl to the // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we @@ -1622,7 +1617,7 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, // This is the first use or definition of a mangled name. If there is a // deferred decl with this name, remember that we need to emit it at the end // of the file. - llvm::StringMap::iterator DDI = DeferredDecls.find(MangledName); + auto DDI = DeferredDecls.find(MangledName); if (DDI != DeferredDecls.end()) { // Move the potentially referenced deferred decl to the DeferredDeclsToEmit // list, and remove it from DeferredDecls (since we don't need it anymore). @@ -3205,6 +3200,15 @@ void CodeGenModule::EmitStaticExternCAliases() { } } +bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName, + GlobalDecl &Result) const { + auto Res = Manglings.find(MangledName); + if (Res == Manglings.end()) + return false; + Result = Res->getValue(); + return true; +} + /// Emits metadata nodes associating all the global values in the /// current module with the Decls they came from. This is useful for /// projects using IR gen as a subroutine. -- cgit v1.1