Create and use an llvm.eh.sjlj.functioncontext intrinsic.

This intrinsic is used to pass the index of the function context to the back-end
for further processing. The back-end is in charge of filling in the rest of the
entries.

llvm-svn: 140676

2 files changed, 14 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 9d86c759b82..b2b93c9ff57 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4754,6 +4754,14 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
     MMI.setCurrentCallSite(CI->getZExtValue());
     return 0;
   }
+  case Intrinsic::eh_sjlj_functioncontext: {
+    // Get and store the index of the function context.
+    MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
+    AllocaInst *FnCtx = cast<AllocaInst>(I.getArgOperand(0));
+    int FI = FuncInfo.StaticAllocaMap[FnCtx];
+    MFI->setFunctionContextIndex(FI);
+    return 0;
+  }
   case Intrinsic::eh_sjlj_setjmp: {
     setValue(&I, DAG.getNode(ISD::EH_SJLJ_SETJMP, dl, MVT::i32, getRoot(),
                              getValue(I.getArgOperand(0))));
diff --git a/llvm/lib/CodeGen/SjLjEHPrepare.cpp b/llvm/lib/CodeGen/SjLjEHPrepare.cpp
index baa70b961b9..9749a7e1191 100644
--- a/llvm/lib/CodeGen/SjLjEHPrepare.cpp
+++ b/llvm/lib/CodeGen/SjLjEHPrepare.cpp
@@ -721,6 +721,12 @@ void SjLjEHPass::setupFunctionContext(Function &F,
   AllocaInst *FuncCtx =
     new AllocaInst(FunctionContextTy, 0, Align, "fn_context", EntryBB->begin());
 
+  // Store a pointer to the function context so that the back-end will know
+  // where to look for it.
+  CallInst::Create(Intrinsic::getDeclaration(F.getParent(),
+                                            Intrinsic::eh_sjlj_functioncontext),
+                   FuncCtx, "", EntryBB->getTerminator());
+
   // Fill in the function context structure.
   Value *Idxs[2];
   Type *Int32Ty = Type::getInt32Ty(F.getContext());