Commit 810b28ed authored by Martin Storsjö's avatar Martin Storsjö
Browse files

[ItaniumCXXABI] Make tls wrappers properly comdat 

Just marking a symbol as weak_odr/linkonce_odr isn't enough for
actually tolerating multiple copies of it at linking on windows,
it has to be made a proper comdat; make it comdat for all platforms
for consistency.

This should hopefully fix
https://bugzilla.mozilla.org/show_bug.cgi?id=1566288.

Differential Revision: https://reviews.llvm.org/D71572
parent 80a094e1

clang/lib/CodeGen/ItaniumCXXABI.cpp

+3 −0
Original line number Diff line number Diff line
@@ -2546,6 +2546,9 @@ ItaniumCXXABI::getOrCreateThreadLocalWrapper(const VarDecl *VD, 
      llvm::Function::Create(FnTy, getThreadLocalWrapperLinkage(VD, CGM),

                             WrapperName.str(), &CGM.getModule());



  if (CGM.supportsCOMDAT() && Wrapper->isWeakForLinker())

    Wrapper->setComdat(CGM.getModule().getOrInsertComdat(Wrapper->getName()));



  CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, Wrapper);



  // Always resolve references to the wrapper at link time.

clang/test/CodeGenCXX/cxx11-thread-local-reference.cpp

+1 −1
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ int &g() { return r; } 
// DARWIN: call cxx_fast_tlscc i32* @_ZTW1r()

// CHECK: ret i32* %{{.*}}



// LINUX: define weak_odr hidden i32* @_ZTW1r() [[ATTR0:#[0-9]+]] {

// LINUX: define weak_odr hidden i32* @_ZTW1r() [[ATTR0:#[0-9]+]] comdat {

// DARWIN: define cxx_fast_tlscc i32* @_ZTW1r() [[ATTR1:#[0-9]+]] {

// LINUX: call void @_ZTH1r()

// DARWIN: call cxx_fast_tlscc void @_ZTH1r()

clang/test/CodeGenCXX/cxx11-thread-local.cpp

+3 −6
Original line number Diff line number Diff line
@@ -204,22 +204,19 @@ int f() { 
// DARWIN: declare i32 @_tlv_atexit(void (i8*)*, i8*, i8*)



// DARWIN: declare cxx_fast_tlscc i32* @_ZTWN1VIcE1mE()

// LINUX: define linkonce_odr hidden i32* @_ZTWN1VIcE1mE()

// LINUX-NOT: comdat

// LINUX: define linkonce_odr hidden i32* @_ZTWN1VIcE1mE() {{#[0-9]+}} comdat {

// LINUX: br i1 icmp ne (void ()* @_ZTHN1VIcE1mE,

// LINUX: call void @_ZTHN1VIcE1mE()

// LINUX: ret i32* @_ZN1VIcE1mE



// DARWIN: declare cxx_fast_tlscc i32* @_ZTWN1WIcE1mE()

// LINUX: define linkonce_odr hidden i32* @_ZTWN1WIcE1mE()

// LINUX-NOT: comdat

// LINUX: define linkonce_odr hidden i32* @_ZTWN1WIcE1mE() {{#[0-9]+}} comdat {

// LINUX: br i1 icmp ne (void ()* @_ZTHN1WIcE1mE,

// LINUX: call void @_ZTHN1WIcE1mE()

// LINUX: ret i32* @_ZN1WIcE1mE



// DARWIN: declare cxx_fast_tlscc {{.*}}* @_ZTWN1XIcE1mE()

// LINUX: define linkonce_odr hidden {{.*}}* @_ZTWN1XIcE1mE()

// LINUX-NOT: comdat

// LINUX: define linkonce_odr hidden {{.*}}* @_ZTWN1XIcE1mE() {{#[0-9]+}} comdat {

// LINUX: br i1 icmp ne (void ()* @_ZTHN1XIcE1mE,

// LINUX: call void @_ZTHN1XIcE1mE()

// LINUX: ret {{.*}}* @_ZN1XIcE1mE

clang/test/CodeGenCXX/tls-init-funcs.cpp

+4 −0
Original line number Diff line number Diff line 
// RUN: %clang_cc1 -triple x86_64-apple-macosx10.8 -std=c++1y -S -emit-llvm %s -o - | FileCheck %s

// RUN: %clang_cc1 -triple x86_64-windows-gnu -std=c++1y -S -emit-llvm %s -o - | FileCheck %s --check-prefix=MINGW



// CHECK: @a = internal thread_local global

// CHECK: @_Z2vtIiE = linkonce_odr thread_local global i32 5
@@ -10,6 +11,9 @@ 
// CHECK-DAG: define weak_odr hidden cxx_fast_tlscc i32* @_ZTW2vtIvE()

// CHECK-DAG: define {{.*}} @_ZTW1a



// MINGW-DAG: define weak_odr hidden i32* @_ZTW2vtIiE() {{.*}} comdat

// MINGW-DAG: define weak_odr hidden i32* @_ZTW2vtIvE() {{.*}} comdat



struct A {

  ~A();

};

clang/test/OpenMP/threadprivate_codegen.cpp

+3 −3
Original line number Diff line number Diff line
@@ -648,15 +648,15 @@ int main() { 
// CHECK-TLS:   call void [[ARR_X_TLS_INIT]]

// CHECK-TLS:   ret [2 x [3 x [[S1]]]]* [[ARR_X]]

// CHECK-TLS: }

// CHECK-TLS: define {{.*}} i32* [[ST_INT_ST_TLS_INITD]] {{#[0-9]+}} {

// CHECK-TLS: define {{.*}} i32* [[ST_INT_ST_TLS_INITD]] {{#[0-9]+}} comdat {

// CHECK-TLS-NOT:   call

// CHECK-TLS:   ret i32* [[ST_INT_ST]]

// CHECK-TLS: }

// CHECK-TLS: define {{.*}} float* [[ST_FLOAT_ST_TLS_INITD]] {{#[0-9]+}} {

// CHECK-TLS: define {{.*}} float* [[ST_FLOAT_ST_TLS_INITD]] {{#[0-9]+}} comdat {

// CHECK-TLS-NOT:   call

// CHECK-TLS:   ret float* [[ST_FLOAT_ST]]

// CHECK-TLS: }

// CHECK-TLS: define {{.*}} [[S4]]* [[ST_S4_ST_TLS_INITD]] {{#[0-9]+}} {

// CHECK-TLS: define {{.*}} [[S4]]* [[ST_S4_ST_TLS_INITD]] {{#[0-9]+}} comdat {

// CHECK-TLS:   call void [[ST_S4_ST_TLS_INIT]]

// CHECK-TLS:   ret [[S4]]* [[ST_S4_ST]]

// CHECK-TLS: }