diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/LowerGlobalDtors.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/LowerGlobalDtors.cpp | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/Utils/LowerGlobalDtors.cpp b/llvm/lib/Transforms/Utils/LowerGlobalDtors.cpp index 195c274ff18e..4908535cba54 100644 --- a/llvm/lib/Transforms/Utils/LowerGlobalDtors.cpp +++ b/llvm/lib/Transforms/Utils/LowerGlobalDtors.cpp @@ -128,7 +128,7 @@ static bool runImpl(Module &M) { // extern "C" int __cxa_atexit(void (*f)(void *), void *p, void *d); LLVMContext &C = M.getContext(); - PointerType *VoidStar = Type::getInt8PtrTy(C); + PointerType *VoidStar = PointerType::getUnqual(C); Type *AtExitFuncArgs[] = {VoidStar}; FunctionType *AtExitFuncTy = FunctionType::get(Type::getVoidTy(C), AtExitFuncArgs, @@ -140,6 +140,17 @@ static bool runImpl(Module &M) { {PointerType::get(AtExitFuncTy, 0), VoidStar, VoidStar}, /*isVarArg=*/false)); + // If __cxa_atexit is defined (e.g. in the case of LTO) and arg0 is not + // actually used (i.e. it's dummy/stub function as used in emscripten when + // the program never exits) we can simply return early and clear out + // @llvm.global_dtors. + if (auto F = dyn_cast<Function>(AtExit.getCallee())) { + if (F && F->hasExactDefinition() && F->getArg(0)->getNumUses() == 0) { + GV->eraseFromParent(); + return true; + } + } + // Declare __dso_local. Type *DsoHandleTy = Type::getInt8Ty(C); Constant *DsoHandle = M.getOrInsertGlobal("__dso_handle", DsoHandleTy, [&] { |