Add -ftls-model command-line flag.
This allows for setting the default TLS model. (PR9788)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159336 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/tools/clang.pod b/docs/tools/clang.pod
index 8f61568..425a91e 100644
--- a/docs/tools/clang.pod
+++ b/docs/tools/clang.pod
@@ -303,6 +303,14 @@
This flag specifies that variables without initializers get common linkage. It
can be disabled with B<-fno-common>.
+=item B<-ftls-model>
+
+Set the default thread-local storage (TLS) model to use for thread-local
+variables. Valid values are: "global-dynamic", "local-dynamic", "initial-exec"
+and "local-exec". The default is "global-dynamic". The default model can be
+overridden with the tls_model attribute. The compiler will try to choose a more
+efficient model if possible.
+
=item B<-flto> B<-emit-llvm>
Generate output files in LLVM formats, suitable for link time optimization. When
diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 0161e2d..6a99b5a 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -648,6 +648,7 @@
def fterminated_vtables : Flag<"-fterminated-vtables">, Alias<fapple_kext>;
def fthreadsafe_statics : Flag<"-fthreadsafe-statics">, Group<f_Group>;
def ftime_report : Flag<"-ftime-report">, Group<f_Group>, Flags<[CC1Option]>;
+def ftlsmodel_EQ : Joined<"-ftls-model=">, Group<f_Group>, Flags<[CC1Option]>;
def ftrapv : Flag<"-ftrapv">, Group<f_Group>, Flags<[CC1Option]>,
HelpText<"Trap on integer overflow">;
def ftrapv_handler_EQ : Joined<"-ftrapv-handler=">, Group<f_Group>,
diff --git a/include/clang/Frontend/CodeGenOptions.h b/include/clang/Frontend/CodeGenOptions.h
index c3ac10c..b36f5f2 100644
--- a/include/clang/Frontend/CodeGenOptions.h
+++ b/include/clang/Frontend/CodeGenOptions.h
@@ -44,6 +44,13 @@
FullDebugInfo // Generate complete debug info.
};
+ enum TLSModel {
+ GeneralDynamicTLSModel,
+ LocalDynamicTLSModel,
+ InitialExecTLSModel,
+ LocalExecTLSModel
+ };
+
unsigned AsmVerbose : 1; ///< -dA, -fverbose-asm.
unsigned ObjCAutoRefCountExceptions : 1; ///< Whether ARC should be EH-safe.
unsigned CUDAIsDevice : 1; ///< Set when compiling for CUDA device.
@@ -175,6 +182,9 @@
/// The run-time penalty for bounds checking, or 0 to disable.
unsigned char BoundsChecking;
+ /// The default TLS model to use.
+ TLSModel DefaultTLSModel;
+
public:
CodeGenOptions() {
AsmVerbose = 0;
@@ -231,6 +241,7 @@
DebugInfo = NoDebugInfo;
Inlining = NoInlining;
RelocationModel = "pic";
+ DefaultTLSModel = GeneralDynamicTLSModel;
}
ObjCDispatchMethodKind getObjCDispatchMethod() const {
diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index 08a9382..be6638e 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -183,26 +183,20 @@
else
Name = GetStaticDeclName(*this, D, Separator);
- llvm::GlobalVariable::ThreadLocalMode TLM;
- TLM = D.isThreadSpecified() ? llvm::GlobalVariable::GeneralDynamicTLSModel
- : llvm::GlobalVariable::NotThreadLocal;
-
- // Set the TLS mode if it it's explicitly specified.
- if (D.hasAttr<TLSModelAttr>()) {
- assert(D.isThreadSpecified() && "Can't have TLS model on non-tls var.");
- const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>();
- TLM = CodeGenModule::GetLLVMTLSModel(Attr->getModel());
- }
-
llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(Ty);
llvm::GlobalVariable *GV =
new llvm::GlobalVariable(CGM.getModule(), LTy,
Ty.isConstant(getContext()), Linkage,
- CGM.EmitNullConstant(D.getType()), Name, 0, TLM,
+ CGM.EmitNullConstant(D.getType()), Name, 0,
+ llvm::GlobalVariable::NotThreadLocal,
CGM.getContext().getTargetAddressSpace(Ty));
GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
if (Linkage != llvm::GlobalValue::InternalLinkage)
GV->setVisibility(CurFn->getVisibility());
+
+ if (D.isThreadSpecified())
+ CGM.setTLSMode(GV, D);
+
return GV;
}
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 8f769d9..25053b9 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -258,6 +258,45 @@
GV->setVisibility(GetLLVMVisibility(LV.visibility()));
}
+static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
+ return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
+ .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
+ .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel)
+ .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel)
+ .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel);
+}
+
+static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(
+ CodeGenOptions::TLSModel M) {
+ switch (M) {
+ case CodeGenOptions::GeneralDynamicTLSModel:
+ return llvm::GlobalVariable::GeneralDynamicTLSModel;
+ case CodeGenOptions::LocalDynamicTLSModel:
+ return llvm::GlobalVariable::LocalDynamicTLSModel;
+ case CodeGenOptions::InitialExecTLSModel:
+ return llvm::GlobalVariable::InitialExecTLSModel;
+ case CodeGenOptions::LocalExecTLSModel:
+ return llvm::GlobalVariable::LocalExecTLSModel;
+ }
+ llvm_unreachable("Invalid TLS model!");
+}
+
+void CodeGenModule::setTLSMode(llvm::GlobalVariable *GV,
+ const VarDecl &D) const {
+ assert(D.isThreadSpecified() && "setting TLS mode on non-TLS var!");
+
+ llvm::GlobalVariable::ThreadLocalMode TLM;
+ TLM = GetLLVMTLSModel(CodeGenOpts.DefaultTLSModel);
+
+ // Override the TLS model if it is explicitly specified.
+ if (D.hasAttr<TLSModelAttr>()) {
+ const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>();
+ TLM = GetLLVMTLSModel(Attr->getModel());
+ }
+
+ GV->setThreadLocalMode(TLM);
+}
+
/// Set the symbol visibility of type information (vtable and RTTI)
/// associated with the given type.
void CodeGenModule::setTypeVisibility(llvm::GlobalValue *GV,
@@ -1212,13 +1251,8 @@
GV->setVisibility(GetLLVMVisibility(LV.visibility()));
}
- GV->setThreadLocal(D->isThreadSpecified());
-
- // Set the TLS model if it it's explicitly specified.
- if (D->hasAttr<TLSModelAttr>()) {
- const TLSModelAttr *Attr = D->getAttr<TLSModelAttr>();
- GV->setThreadLocalMode(GetLLVMTLSModel(Attr->getModel()));
- }
+ if (D->isThreadSpecified())
+ setTLSMode(GV, *D);
}
if (AddrSpace != Ty->getAddressSpace())
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index a742d84..d6ff50d 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -474,6 +474,10 @@
/// GlobalValue.
void setGlobalVisibility(llvm::GlobalValue *GV, const NamedDecl *D) const;
+ /// setTLSMode - Set the TLS mode for the given LLVM GlobalVariable
+ /// for the thread-local variable declaration D.
+ void setTLSMode(llvm::GlobalVariable *GV, const VarDecl &D) const;
+
/// TypeVisibilityKind - The kind of global variable that is passed to
/// setTypeVisibility
enum TypeVisibilityKind {
@@ -498,15 +502,6 @@
llvm_unreachable("unknown visibility!");
}
- static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
- return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
- .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
- .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel)
- .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel)
- .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel)
- .Default(llvm::GlobalVariable::NotThreadLocal);
- }
-
llvm::Constant *GetAddrOfGlobal(GlobalDecl GD) {
if (isa<CXXConstructorDecl>(GD.getDecl()))
return GetAddrOfCXXConstructor(cast<CXXConstructorDecl>(GD.getDecl()),
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index c3ea22f..c5a837f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -2209,6 +2209,8 @@
Args.AddLastArg(CmdArgs, options::OPT_fvisibility_inlines_hidden);
+ Args.AddLastArg(CmdArgs, options::OPT_ftlsmodel_EQ);
+
// -fhosted is default.
if (Args.hasFlag(options::OPT_ffreestanding, options::OPT_fhosted, false) ||
KernelOrKext)
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 40328d4..4100dea 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -307,6 +307,20 @@
Res.push_back("-disable-llvm-verifier");
for (unsigned i = 0, e = Opts.BackendOptions.size(); i != e; ++i)
Res.push_back("-backend-option", Opts.BackendOptions[i]);
+
+ switch (Opts.DefaultTLSModel) {
+ case CodeGenOptions::GeneralDynamicTLSModel:
+ break;
+ case CodeGenOptions::LocalDynamicTLSModel:
+ Res.push_back("-ftls-model=local-dynamic");
+ break;
+ case CodeGenOptions::InitialExecTLSModel:
+ Res.push_back("-ftls-model=initial-exec");
+ break;
+ case CodeGenOptions::LocalExecTLSModel:
+ Res.push_back("-ftls-model=local-exec");
+ break;
+ }
}
static void DependencyOutputOptsToArgs(const DependencyOutputOptions &Opts,
@@ -788,7 +802,7 @@
if (Opts.AppleKext)
Res.push_back("-fapple-kext");
-
+
if (Opts.getVisibilityMode() != DefaultVisibility) {
Res.push_back("-fvisibility");
if (Opts.getVisibilityMode() == HiddenVisibility) {
@@ -1256,6 +1270,22 @@
}
}
+ if (Arg *A = Args.getLastArg(OPT_ftlsmodel_EQ)) {
+ StringRef Name = A->getValue(Args);
+ unsigned Model = llvm::StringSwitch<unsigned>(Name)
+ .Case("global-dynamic", CodeGenOptions::GeneralDynamicTLSModel)
+ .Case("local-dynamic", CodeGenOptions::LocalDynamicTLSModel)
+ .Case("initial-exec", CodeGenOptions::InitialExecTLSModel)
+ .Case("local-exec", CodeGenOptions::LocalExecTLSModel)
+ .Default(~0U);
+ if (Model == ~0U) {
+ Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Name;
+ Success = false;
+ } else {
+ Opts.DefaultTLSModel = static_cast<CodeGenOptions::TLSModel>(Model);
+ }
+ }
+
return Success;
}
diff --git a/test/CodeGen/tls-model.c b/test/CodeGen/tls-model.c
new file mode 100644
index 0000000..b5bae77
--- /dev/null
+++ b/test/CodeGen/tls-model.c
@@ -0,0 +1,28 @@
+// RUN: %clang_cc1 %s -triple x86_64-pc-linux-gnu -emit-llvm -o - | FileCheck %s -check-prefix=CHECK-GD
+// RUN: %clang_cc1 %s -triple x86_64-pc-linux-gnu -ftls-model=global-dynamic -emit-llvm -o - | FileCheck %s -check-prefix=CHECK-GD
+// RUN: %clang_cc1 %s -triple x86_64-pc-linux-gnu -ftls-model=local-dynamic -emit-llvm -o - | FileCheck %s -check-prefix=CHECK-LD
+// RUN: %clang_cc1 %s -triple x86_64-pc-linux-gnu -ftls-model=initial-exec -emit-llvm -o - | FileCheck %s -check-prefix=CHECK-IE
+// RUN: %clang_cc1 %s -triple x86_64-pc-linux-gnu -ftls-model=local-exec -emit-llvm -o - | FileCheck %s -check-prefix=CHECK-LE
+
+int __thread x;
+int f() {
+ static int __thread y;
+ return y++;
+}
+int __thread __attribute__((tls_model("initial-exec"))) z;
+
+// CHECK-GD: @f.y = internal thread_local global i32 0
+// CHECK-GD: @x = thread_local global i32 0
+// CHECK-GD: @z = thread_local(initialexec) global i32 0
+
+// CHECK-LD: @f.y = internal thread_local(localdynamic) global i32 0
+// CHECK-LD: @x = thread_local(localdynamic) global i32 0
+// CHECK-LD: @z = thread_local(initialexec) global i32 0
+
+// CHECK-IE: @f.y = internal thread_local(initialexec) global i32 0
+// CHECK-IE: @x = thread_local(initialexec) global i32 0
+// CHECK-IE: @z = thread_local(initialexec) global i32 0
+
+// CHECK-LE: @f.y = internal thread_local(localexec) global i32 0
+// CHECK-LE: @x = thread_local(localexec) global i32 0
+// CHECK-LE: @z = thread_local(initialexec) global i32 0
