[slydiman]

Added the CAS statistics stored in the binary stats file in CAS directory.
llvm-cas --show-stats -cas <CASPath> shows something like

llvm-cas: stats:
Cache hits:                      766
Cache misses:                    924
Cache misses (result_not_found): 0
Cache backend output not found:  0
Cache skipped:                   0
Average depscan:                 0.122599 s (1690)
Average backend key query:       0.000005 s (1690)
Average backend key update:      0.000011 s (853)
Average backend load:            0.003442 s (766)
Average backend store:           0.000018 s (853)
Cache location: <CASPath>

llvm-cas --zero-stats -cas <CASPath> resets the statistics.
Note the compiler should use -Xclang -Rcompile-job-cache-timing -Xclang -Rcompile-job-cache to get it working.
We can disable CacheStatsDiagnosticConsumer if compile-job-cache remarks are disabled.
We can create custom remarks enabled by default and add extra Diag.Report() wherever compile-job-cache-* are reported.
Note TextDiagnosticPrinter will print compile-job-cache or any custom remarks anyway to stdout.

[tagolog]

Is this commented-out code still needed, or can we safely remove it?

[slydiman]

Sure, we can remove it.