[SystemZ] Implement getRepRegClassFor()

This method must return a valid register class, or the list-ilp isel
scheduler will crash. For MVT::Untyped nullptr was previously returned, but
now ADDR128BitRegClass is returned instead. This is needed just as long as
list-ilp (and probably also list-hybrid) is still there.

Review: Ulrich Weigand, A Trick
https://reviews.llvm.org/D32802

llvm-svn: 302649

2 files changed, 11 insertions, 0 deletions

diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
index ac736c25bcf..235e095f001 100644
--- a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
@@ -6352,3 +6352,12 @@ MachineBasicBlock *SystemZTargetLowering::EmitInstrWithCustomInserter(
     llvm_unreachable("Unexpected instr type to insert");
   }
 }
+
+// This is only used by the isel schedulers, and is needed only to prevent
+// compiler from crashing when list-ilp is used.
+const TargetRegisterClass *
+SystemZTargetLowering::getRepRegClassFor(MVT VT) const {
+  if (VT == MVT::Untyped)
+    return &SystemZ::ADDR128BitRegClass;
+  return TargetLowering::getRepRegClassFor(VT);
+}
diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.h b/llvm/lib/Target/SystemZ/SystemZISelLowering.h
index 1c34dc43e8b..79c8c4d9266 100644
--- a/llvm/lib/Target/SystemZ/SystemZISelLowering.h
+++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.h
@@ -590,6 +590,8 @@ private:
   MachineBasicBlock *emitLoadAndTestCmp0(MachineInstr &MI,
                                          MachineBasicBlock *MBB,
                                          unsigned Opcode) const;
+
+  const TargetRegisterClass *getRepRegClassFor(MVT VT) const override;
 };
 } // end namespace llvm