Summary: By using reg_nodbg_empty() to determine if a function can be
treated as a leaf function or not, we miss the case when the register
pair L0_L1 is used but not L0 by itself. This has the effect that
use_all_i32_regs(), a test in reserved-regs.ll which tries to use all
registers, gets treated as a leaf function.
Reviewers: jyknight, venkatra
Reviewed By: jyknight
Subscribers: davide, RKSimon, sepavloff, llvm-commits
Differential Revision: https://reviews.llvm.org/D27089
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297285 91177308-0d34-0410-b5e6-96231b3b80d8