Call __cxa_begin_catch with the current exception before
calling std::terminate(). rdar://11904428
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174940 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGException.cpp b/lib/CodeGen/CGException.cpp
index b232925..8dced63 100644
--- a/lib/CodeGen/CGException.cpp
+++ b/lib/CodeGen/CGException.cpp
@@ -1516,6 +1516,65 @@
CGF.PopCleanupBlock();
}
+/// In a terminate landing pad, should we use __clang__call_terminate
+/// or just a naked call to std::terminate?
+///
+/// __clang_call_terminate calls __cxa_begin_catch, which then allows
+/// std::terminate to usefully report something about the
+/// violating exception.
+static bool useClangCallTerminate(CodeGenModule &CGM) {
+ // Only do this for Itanium-family ABIs in C++ mode.
+ return (CGM.getLangOpts().CPlusPlus &&
+ CGM.getTarget().getCXXABI().isItaniumFamily());
+}
+
+/// Get or define the following function:
+/// void @__clang_call_terminate(i8* %exn) nounwind noreturn
+/// This code is used only in C++.
+static llvm::Constant *getClangCallTerminateFn(CodeGenModule &CGM) {
+ llvm::FunctionType *fnTy =
+ llvm::FunctionType::get(CGM.VoidTy, CGM.Int8PtrTy, /*IsVarArgs=*/false);
+ llvm::Constant *fnRef =
+ CGM.CreateRuntimeFunction(fnTy, "__clang_call_terminate");
+
+ llvm::Function *fn = dyn_cast<llvm::Function>(fnRef);
+ if (fn && fn->empty()) {
+ fn->setDoesNotThrow();
+ fn->setDoesNotReturn();
+
+ // What we really want is to massively penalize inlining without
+ // forbidding it completely. The difference between that and
+ // 'noinline' is negligible.
+ fn->addFnAttr(llvm::Attribute::NoInline);
+
+ // Allow this function to be shared across translation units, but
+ // we don't want it to turn into an exported symbol.
+ fn->setLinkage(llvm::Function::LinkOnceODRLinkage);
+ fn->setVisibility(llvm::Function::HiddenVisibility);
+
+ // Set up the function.
+ llvm::BasicBlock *entry =
+ llvm::BasicBlock::Create(CGM.getLLVMContext(), "", fn);
+ CGBuilderTy builder(entry);
+
+ // Pull the exception pointer out of the parameter list.
+ llvm::Value *exn = &*fn->arg_begin();
+
+ // Call __cxa_begin_catch(exn).
+ builder.CreateCall(getBeginCatchFn(CGM), exn)->setDoesNotThrow();
+
+ // Call std::terminate().
+ llvm::CallInst *termCall = builder.CreateCall(getTerminateFn(CGM));
+ termCall->setDoesNotThrow();
+ termCall->setDoesNotReturn();
+
+ // std::terminate cannot return.
+ builder.CreateUnreachable();
+ }
+
+ return fnRef;
+}
+
llvm::BasicBlock *CodeGenFunction::getTerminateLandingPad() {
if (TerminateLandingPad)
return TerminateLandingPad;
@@ -1533,9 +1592,16 @@
getOpaquePersonalityFn(CGM, Personality), 0);
LPadInst->addClause(getCatchAllValue(*this));
- llvm::CallInst *TerminateCall = Builder.CreateCall(getTerminateFn(CGM));
- TerminateCall->setDoesNotReturn();
- TerminateCall->setDoesNotThrow();
+ llvm::CallInst *terminateCall;
+ if (useClangCallTerminate(CGM)) {
+ // Extract out the exception pointer.
+ llvm::Value *exn = Builder.CreateExtractValue(LPadInst, 0);
+ terminateCall = Builder.CreateCall(getClangCallTerminateFn(CGM), exn);
+ } else {
+ terminateCall = Builder.CreateCall(getTerminateFn(CGM));
+ }
+ terminateCall->setDoesNotReturn();
+ terminateCall->setDoesNotThrow();
Builder.CreateUnreachable();
// Restore the saved insertion state.