diff options
| -rw-r--r-- | clang/include/clang/Driver/Options.td | 3 | ||||
| -rw-r--r-- | clang/include/clang/Frontend/CodeGenOptions.def | 3 | ||||
| -rw-r--r-- | clang/lib/CodeGen/CodeGenModule.cpp | 13 | ||||
| -rw-r--r-- | clang/lib/Driver/ToolChains/Clang.cpp | 1 | ||||
| -rw-r--r-- | clang/lib/Frontend/CompilerInvocation.cpp | 2 | ||||
| -rw-r--r-- | clang/test/CodeGen/keep-static-consts.cpp | 6 |
6 files changed, 27 insertions, 1 deletions
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td index 6e45f2aef63..5d27a9a7dc9 100644 --- a/clang/include/clang/Driver/Options.td +++ b/clang/include/clang/Driver/Options.td @@ -893,7 +893,8 @@ def fforce_enable_int128 : Flag<["-"], "fforce-enable-int128">, def fno_force_enable_int128 : Flag<["-"], "fno-force-enable-int128">, Group<f_Group>, Flags<[CC1Option]>, HelpText<"Disable support for int128_t type">; - +def fkeep_static_consts : Flag<["-"], "fkeep-static-consts">, Group<f_Group>, Flags<[CC1Option]>, + HelpText<"Keep static const variables even if unused">; def ffixed_point : Flag<["-"], "ffixed-point">, Group<f_Group>, Flags<[CC1Option]>, HelpText<"Enable fixed point types">; def fno_fixed_point : Flag<["-"], "fno-fixed-point">, Group<f_Group>, diff --git a/clang/include/clang/Frontend/CodeGenOptions.def b/clang/include/clang/Frontend/CodeGenOptions.def index 06aeea0ab89..4968e7b2bf3 100644 --- a/clang/include/clang/Frontend/CodeGenOptions.def +++ b/clang/include/clang/Frontend/CodeGenOptions.def @@ -341,6 +341,9 @@ CODEGENOPT(Addrsig, 1, 0) ENUM_CODEGENOPT(SignReturnAddress, SignReturnAddressScope, 2, None) +/// Whether to emit unused static constants. +CODEGENOPT(KeepStaticConsts, 1, 0) + #undef CODEGENOPT #undef ENUM_CODEGENOPT #undef VALUE_CODEGENOPT diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index aaaf6c6d754..29692eedb53 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -1350,6 +1350,12 @@ void CodeGenModule::SetCommonAttributes(GlobalDecl GD, llvm::GlobalValue *GV) { if (D && D->hasAttr<UsedAttr>()) addUsedGlobal(GV); + + if (CodeGenOpts.KeepStaticConsts && D && isa<VarDecl>(D)) { + const auto *VD = cast<VarDecl>(D); + if (VD->getType().isConstQualified() && VD->getStorageClass() == SC_Static) + addUsedGlobal(GV); + } } bool CodeGenModule::GetCPUAndFeaturesAttributes(const Decl *D, @@ -1985,6 +1991,13 @@ bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) { if (LangOpts.EmitAllDecls) return true; + if (CodeGenOpts.KeepStaticConsts) { + const auto *VD = dyn_cast<VarDecl>(Global); + if (VD && VD->getType().isConstQualified() && + VD->getStorageClass() == SC_Static) + return true; + } + return getContext().DeclMustBeEmitted(Global); } diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp index 135d40fc700..45c63d54301 100644 --- a/clang/lib/Driver/ToolChains/Clang.cpp +++ b/clang/lib/Driver/ToolChains/Clang.cpp @@ -4008,6 +4008,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA, Args.AddLastArg(CmdArgs, options::OPT_fno_operator_names); Args.AddLastArg(CmdArgs, options::OPT_femulated_tls, options::OPT_fno_emulated_tls); + Args.AddLastArg(CmdArgs, options::OPT_fkeep_static_consts); // AltiVec-like language extensions aren't relevant for assembling. if (!isa<PreprocessJobAction>(JA) || Output.getType() != types::TY_PP_Asm) diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index 8e836b163ef..78ed8f78207 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -1145,6 +1145,8 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK, << A->getAsString(Args) << A->getValue(); } + Opts.KeepStaticConsts = Args.hasArg(OPT_fkeep_static_consts); + return Success; } diff --git a/clang/test/CodeGen/keep-static-consts.cpp b/clang/test/CodeGen/keep-static-consts.cpp new file mode 100644 index 00000000000..3cdac7ad1ad --- /dev/null +++ b/clang/test/CodeGen/keep-static-consts.cpp @@ -0,0 +1,6 @@ +// RUN: %clang_cc1 -fkeep-static-consts -emit-llvm %s -o - -triple=x86_64-unknown-linux-gnu | FileCheck %s + +// CHECK: @_ZL7srcvers = internal constant [4 x i8] c"xyz\00", align 1 +// CHECK: @llvm.used = appending global [1 x i8*] [i8* getelementptr inbounds ([4 x i8], [4 x i8]* @_ZL7srcvers, i32 0, i32 0)], section "llvm.metadata" +static const char srcvers[] = "xyz"; +extern const int b = 1; |
