[PowerPC] Better fix for PR16556.

A more complete example of the bug in PR16556 was recently provided,
showing that the previous fix was not sufficient.  The previous fix is
reverted herein.

The real problem is that ReplaceNodeResults() uses LowerFP_TO_INT as
custom lowering for FP_TO_SINT during type legalization, without
checking whether the input type is handled by that routine.
LowerFP_TO_INT requires the input to be f32 or f64, so we fail when
the input is ppcf128.

I'm leaving the test case from the initial fix (r185821) in place, and
adding the new test as another crash-only check.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185959 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 9 deletions

diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 812f096..791d334 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -4720,15 +4720,6 @@ SDValue PPCTargetLowering::LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG,
                                            SDLoc dl) const {
   assert(Op.getOperand(0).getValueType().isFloatingPoint());
   SDValue Src = Op.getOperand(0);
-
-  // If we have a long double here, it must be that we have an undef of
-  // that type.  In this case return an undef of the target type.
-  if (Src.getValueType() == MVT::ppcf128) {
-    assert(Src.getOpcode() == ISD::UNDEF && "Unhandled ppcf128!");
-    return DAG.getNode(ISD::UNDEF, dl,
-                       Op.getValueType().getSimpleVT().SimpleTy);
-  }
-
   if (Src.getValueType() == MVT::f32)
     Src = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Src);
 
@@ -5808,6 +5799,9 @@ void PPCTargetLowering::ReplaceNodeResults(SDNode *N,
     return;
   }
   case ISD::FP_TO_SINT:
+    // LowerFP_TO_INT() can only handle f32 and f64.
+    if (N->getOperand(0).getValueType() == MVT::ppcf128)
+      return;
     Results.push_back(LowerFP_TO_INT(SDValue(N, 0), DAG, dl));
     return;
   }