CS nested profile has a benefit over the CS flat profile that is to speed up the build while achieve an on-par performance. I'm turning it on by default for CSSPGO.
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D121142
For reducing binary size purpose, the binary's debug info and executable segment can be separated(like using objcopy --only-keep-debug). Here add support in llvm-profgen to use two binaries as input. The original one is executable binary and added for debug info only binary. Adding a flag `--debug-binary=file-path`, with this, the binary will load debug info from debug binary.
Reviewed By: hoy, wenlei
Differential Revision: https://reviews.llvm.org/D115948
Hongtao Yu