The test case in https://bugs.llvm.org/show_bug.cgi?id=47373 exposed
two bugs in the PPC back end. The first one was fixed in commit
2771407584 but the test case had to
be added without -verify-machineinstrs due to the second bug.
This commit fixes the use-after-kill that is left behind by the
PPC MI peephole optimization.
The function emitRLDICWhenLoweringJumpTables in PPCMIPeephole.cpp
was supposed to convert a pair of RLDICL and RLDICR to a single RLDIC,
but it was leaving out the RLDICL instruction. This PR fixes the bug.
Differential Revision: https://reviews.llvm.org/D78063