Fix __builtin_setjmp in combination with sjlj exception handling.
llvm.eh.sjlj.setjmp was used as part of the SjLj exception handling
style but is also used in clang to implement __builtin_setjmp. The ARM
backend needs to output additional dispatch tables for the SjLj
exception handling style, these tables however can't be emitted if
llvm.eh.sjlj.setjmp is simply used for __builtin_setjmp and no actual
landing pad blocks exist.
To solve this issue a new llvm.eh.sjlj.setup_dispatch intrinsic is
introduced which is used instead of llvm.eh.sjlj.setjmp in the SjLj
exception handling lowering, so we can differentiate between the case
where we actually need to setup a dispatch table and the case where we
just need the __builtin_setjmp semantic.
Differential Revision: http://reviews.llvm.org/D9313
llvm-svn: 242481
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 51057a0..0396736 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1264,6 +1264,7 @@
case ISD::FRAME_TO_ARGS_OFFSET:
case ISD::EH_SJLJ_SETJMP:
case ISD::EH_SJLJ_LONGJMP:
+ case ISD::EH_SJLJ_SETUP_DISPATCH:
// These operations lie about being legal: when they claim to be legal,
// they should actually be expanded.
Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 73de6e3..702e14b 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4410,6 +4410,11 @@
getRoot(), getValue(I.getArgOperand(0))));
return nullptr;
}
+ case Intrinsic::eh_sjlj_setup_dispatch: {
+ DAG.setRoot(DAG.getNode(ISD::EH_SJLJ_SETUP_DISPATCH, sdl, MVT::Other,
+ getRoot()));
+ return nullptr;
+ }
case Intrinsic::masked_gather:
visitMaskedGather(I);
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
index 8dabddc..883cc257 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
@@ -102,6 +102,7 @@
case ISD::EH_RETURN: return "EH_RETURN";
case ISD::EH_SJLJ_SETJMP: return "EH_SJLJ_SETJMP";
case ISD::EH_SJLJ_LONGJMP: return "EH_SJLJ_LONGJMP";
+ case ISD::EH_SJLJ_SETUP_DISPATCH: return "EH_SJLJ_SETUP_DISPATCH";
case ISD::ConstantPool: return "ConstantPool";
case ISD::TargetIndex: return "TargetIndex";
case ISD::ExternalSymbol: return "ExternalSymbol";
diff --git a/llvm/lib/CodeGen/SjLjEHPrepare.cpp b/llvm/lib/CodeGen/SjLjEHPrepare.cpp
index d236e1f..2a16b64 100644
--- a/llvm/lib/CodeGen/SjLjEHPrepare.cpp
+++ b/llvm/lib/CodeGen/SjLjEHPrepare.cpp
@@ -50,7 +50,7 @@
Type *FunctionContextTy;
Constant *RegisterFn;
Constant *UnregisterFn;
- Constant *BuiltinSetjmpFn;
+ Constant *BuiltinSetupDispatchFn;
Constant *FrameAddrFn;
Constant *StackAddrFn;
Constant *StackRestoreFn;
@@ -112,7 +112,8 @@
FrameAddrFn = Intrinsic::getDeclaration(&M, Intrinsic::frameaddress);
StackAddrFn = Intrinsic::getDeclaration(&M, Intrinsic::stacksave);
StackRestoreFn = Intrinsic::getDeclaration(&M, Intrinsic::stackrestore);
- BuiltinSetjmpFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_setjmp);
+ BuiltinSetupDispatchFn =
+ Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_setup_dispatch);
LSDAAddrFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_lsda);
CallSiteFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_callsite);
FuncCtxFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_functioncontext);
@@ -421,9 +422,8 @@
Val = Builder.CreateCall(StackAddrFn, {}, "sp");
Builder.CreateStore(Val, StackPtr, /*isVolatile=*/true);
- // Call the setjmp instrinsic. It fills in the rest of the jmpbuf.
- Value *SetjmpArg = Builder.CreateBitCast(JBufPtr, Builder.getInt8PtrTy());
- Builder.CreateCall(BuiltinSetjmpFn, SetjmpArg);
+ // Call the setup_dispatch instrinsic. It fills in the rest of the jmpbuf.
+ Builder.CreateCall(BuiltinSetupDispatchFn, {});
// Store a pointer to the function context so that the back-end will know
// where to look for it.