; Test that the backend does not mess up the I/R in case of a use of an undef ; register. This typically happens while expanding a pseudo or otherwise ; replacing an instruction for another. ; ; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z13 -verify-machineinstrs | FileCheck %s ; LLCRMux define void @f1(i8*) { ; CHECK-LABEL: f1: ; CHECK-NOT: *** Bad machine code: Using an undefined physical register *** BB: %L5 = load i8, i8* %0 %B9 = lshr i8 %L5, -1 br label %CF CF: ; preds = %CF, %BB %Cmp25 = icmp ne i8 27, %B9 br i1 %Cmp25, label %CF, label %CF34 CF34: ; preds = %CF ret void }