Make sure :push_loc meta always has a corresponding :pop_loc

[yuyichao]

• Preserve meta node and line number info during dead code elimination
• Insert :push_loc and :pop_loc in pairs during lowering

Fix #16578

[yuyichao]

This adds a SSAValue in some cases so

@nanosoldier runbenchmarks(ALL, vs = ":master")

Also, why is circleci trying to build on this pr without a config file?

[tkelman]

Also, why is circleci trying to build on this pr without a config file?

Because it's kinda dumb. Ignore it while we try to get #18007 up and running.

[nanosoldier]

Something went wrong when running your job: RemoteException(2,CapturedException(NanosoldierError: failed to run benchmarks against primary commit: ErrorException("failed process: Process(make, ProcessExited(2)) [2]"),Any[( in pipeline_error at process.jl:612,1),( in run at process.jl:588,1),( in build_julia! at build.jl:54,1),( in execute_benchmarks! at BenchmarkJob.jl:251,1),( in run at BenchmarkJob.jl:178,1),( in #503 at multi.jl:1410,1),( in run_work_thunk at multi.jl:996,1),( in macro expansion at multi.jl:1410 [inlined],1),( in #502 at event.jl:46,1)]))
cc @jrevels

[tkelman]

We should probably revert #18164 until we're sure it works from a clean build. I guess a side effect of running nanosoldier more often is that it tests that configuration, and on a fast enough machine that it doesn't take forever to do so.

[yuyichao]

@nanosoldier runbenchmarks(ALL, vs = ":master")

[nanosoldier]

Your benchmark job has completed - possible performance regressions were detected. A full report can be found here. cc @jrevels

[yuyichao]

Comment? I can't really reproduce the two regressions in the nanosoldier report so I'm tempting to believe it's just noise.