[GlobalISel][Legalizer] Fix crash when trying to lower G_FNEG of fp128 types.

This doesn't add legalizer support, just prevents crashing so that we
can gracefully fall back to SDAG.

Fixes PR35690.

llvm-svn: 321091

1 files changed, 3 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 87a658be4c2..a3b43c92a7f 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -835,6 +835,9 @@ LegalizerHelper::lower(MachineInstr &MI, unsigned TypeIdx, LLT Ty) {
     case 64:
       ZeroTy = Type::getDoubleTy(Ctx);
       break;
+    case 128:
+      ZeroTy = Type::getFP128Ty(Ctx);
+      break;
     default:
       llvm_unreachable("unexpected floating-point type");
     }