From d7ba46b287c29f8b188a6515f3911bb7817a455d Mon Sep 17 00:00:00 2001 From: Yaron Keren Date: Sat, 19 Apr 2014 13:47:43 +0000 Subject: Patch by Vadim Chugunov Win64 stack unwinder gets confused when execution flow "falls through" after a call to 'noreturn' function. This fixes the "missing epilogue" problem by emitting a trap instruction for IR 'unreachable' on x86_x64-pc-windows. A secondary use for it would be for anyone wanting to make double-sure that 'noreturn' functions, indeed, do not return. llvm-svn: 206684 --- llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index 06cd8b31c8b..1aaac5fc3c3 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -2765,6 +2765,11 @@ void SelectionDAGBuilder::visitIndirectBr(const IndirectBrInst &I) { getValue(I.getAddress()))); } +void SelectionDAGBuilder::visitUnreachable(const UnreachableInst &I) { + if (DAG.getTarget().Options.TrapUnreachable) + DAG.setRoot(DAG.getNode(ISD::TRAP, getCurSDLoc(), MVT::Other, DAG.getRoot())); +} + void SelectionDAGBuilder::visitFSub(const User &I) { // -0.0 - X --> fneg Type *Ty = I.getType(); -- cgit v1.2.3