Add a pre-dispatch SjLj EH hook on the unwind edge for targets to do any
setup they require. Use this for ARM/Darwin to rematerialize the base
pointer from the frame pointer when required. rdar://8564268
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116879 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index c777949..cd40f64 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -865,6 +865,7 @@
case ISD::FRAME_TO_ARGS_OFFSET:
case ISD::EH_SJLJ_SETJMP:
case ISD::EH_SJLJ_LONGJMP:
+ case ISD::EH_SJLJ_DISPATCHSETUP:
// 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));
@@ -2541,9 +2542,14 @@
case ISD::PREFETCH:
case ISD::VAEND:
case ISD::EH_SJLJ_LONGJMP:
+ case ISD::EH_SJLJ_DISPATCHSETUP:
+ // If the target didn't expand these, there's nothing to do, so just
+ // preserve the chain and be done.
Results.push_back(Node->getOperand(0));
break;
case ISD::EH_SJLJ_SETJMP:
+ // If the target didn't expand this, just return 'zero' and preserve the
+ // chain.
Results.push_back(DAG.getConstant(0, MVT::i32));
Results.push_back(Node->getOperand(0));
break;
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index c6eb216..f52c931 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -5616,6 +5616,7 @@
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_DISPATCHSETUP: return "EH_SJLJ_DISPATCHSETUP";
case ISD::ConstantPool: return "ConstantPool";
case ISD::ExternalSymbol: return "ExternalSymbol";
case ISD::BlockAddress: return "BlockAddress";
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 04c424f..e2b1bb4 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4319,8 +4319,12 @@
}
case Intrinsic::eh_sjlj_longjmp: {
DAG.setRoot(DAG.getNode(ISD::EH_SJLJ_LONGJMP, dl, MVT::Other,
- getRoot(),
- getValue(I.getArgOperand(0))));
+ getRoot(), getValue(I.getArgOperand(0))));
+ return 0;
+ }
+ case Intrinsic::eh_sjlj_dispatch_setup: {
+ DAG.setRoot(DAG.getNode(ISD::EH_SJLJ_DISPATCHSETUP, dl, MVT::Other,
+ getRoot(), getValue(I.getArgOperand(0))));
return 0;
}
diff --git a/lib/CodeGen/SjLjEHPrepare.cpp b/lib/CodeGen/SjLjEHPrepare.cpp
index b637980..1f6a5c4 100644
--- a/lib/CodeGen/SjLjEHPrepare.cpp
+++ b/lib/CodeGen/SjLjEHPrepare.cpp
@@ -53,6 +53,7 @@
Constant *SelectorFn;
Constant *ExceptionFn;
Constant *CallSiteFn;
+ Constant *DispatchSetupFn;
Value *CallSite;
public:
@@ -116,6 +117,8 @@
SelectorFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_selector);
ExceptionFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_exception);
CallSiteFn = Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_callsite);
+ DispatchSetupFn
+ = Intrinsic::getDeclaration(&M, Intrinsic::eh_sjlj_dispatch_setup);
PersonalityFn = 0;
return true;
@@ -438,9 +441,17 @@
BasicBlock *DispatchBlock =
BasicBlock::Create(F.getContext(), "eh.sjlj.setjmp.catch", &F);
- // Insert a load in the Catch block, and a switch on its value. By default,
- // we go to a block that just does an unwind (which is the correct action
- // for a standard call).
+ // Add a call to dispatch_setup at the start of the dispatch block. This
+ // is expanded to any target-specific setup that needs to be done.
+ Value *SetupArg =
+ CastInst::Create(Instruction::BitCast, FunctionContext,
+ Type::getInt8PtrTy(F.getContext()), "",
+ DispatchBlock);
+ CallInst::Create(DispatchSetupFn, SetupArg, "", DispatchBlock);
+
+ // Insert a load of the callsite in the dispatch block, and a switch on
+ // its value. By default, we go to a block that just does an unwind
+ // (which is the correct action for a standard call).
BasicBlock *UnwindBlock =
BasicBlock::Create(F.getContext(), "unwindbb", &F);
Unwinds.push_back(new UnwindInst(F.getContext(), UnwindBlock));