diff options
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 5 | ||||
| -rw-r--r-- | test/CodeGen/X86/tailcall-fastisel.ll | 14 |
2 files changed, 15 insertions, 4 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index 3f8c593a91..17cc6bf31b 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -4649,6 +4649,11 @@ void SelectionDAGBuilder::LowerCallTo(ImmutableCallSite CS, SDValue Callee, !isInTailCallPosition(CS, CS.getAttributes().getRetAttributes(), TLI)) isTailCall = false; + // If there's a possibility that fast-isel has already selected some amount + // of the current basic block, don't emit a tail call. + if (isTailCall && EnableFastISel) + isTailCall = false; + std::pair<SDValue,SDValue> Result = TLI.LowerCallTo(getRoot(), RetTy, CS.paramHasAttr(0, Attribute::SExt), diff --git a/test/CodeGen/X86/tailcall-fastisel.ll b/test/CodeGen/X86/tailcall-fastisel.ll index d54fb4115b..7f92af4dca 100644 --- a/test/CodeGen/X86/tailcall-fastisel.ll +++ b/test/CodeGen/X86/tailcall-fastisel.ll @@ -1,8 +1,6 @@ -; RUN: llc < %s -march=x86-64 -tailcallopt -fast-isel | grep TAILCALL +; RUN: llc < %s -march=x86-64 -tailcallopt -fast-isel | not grep TAILCALL -; Fast-isel shouldn't attempt to handle this tail call, and it should -; cleanly terminate instruction selection in the block after it's -; done to avoid emitting invalid MachineInstrs. +; Fast-isel shouldn't attempt to cope with tail calls. %0 = type { i64, i32, i8* } @@ -11,3 +9,11 @@ fail: ; preds = %entry %tmp20 = tail call fastcc i8* @"visit_array_aux<`Reference>"(%0 %arg, i32 undef) ; <i8*> [#uses=1] ret i8* %tmp20 } + +define i32 @foo() nounwind { +entry: + %0 = tail call i32 (...)* @bar() nounwind ; <i32> [#uses=1] + ret i32 %0 +} + +declare i32 @bar(...) nounwind |