[SIL] Deprecating the '-gsil' frontend flag

[mshockwave]

The -gsil is deprecated in favor of -sil-based-debuginfo.

This PR is a synergy with swiftlang/swift#38167.

[mshockwave]

@swift-ci test

[adrian-prantl]

LGTM form my side, but please wait for @nkcsgexi to also approve the PR.

[adrian-prantl]

We may have an exhaustive list of the existing -gsil userbase in the list of Reviewers now 😀

[atrick]

Sweet!

[adrian-prantl]

@mshockwave For the odd chance that there are other users of -gsil: Since we don't use -gsil for anything else — should we define it and print a "this option is deprecated" error or alias it to the new option?

[mshockwave]

@mshockwave For the odd chance that there are other users of -gsil: Since we don't use -gsil for anything else — should we define it and print a "this option is deprecated" error or alias it to the new option?

Yes I can do that

[mshockwave]

@mshockwave For the odd chance that there are other users of -gsil: Since we don't use -gsil for anything else — should we define it and print a "this option is deprecated" error or alias it to the new option?

Yes I can do that

Please refer to swiftlang/swift#38167 (comment)

@swift-ci test

[nkcsgexi]

LGTM!

[nkcsgexi]

The patch looks great to me! For future reference, we don't have to update the option list if the driver code doesn't use any new options in the implementation. The option list will be eventually updated by later changes.

[mshockwave]

Reflecting the updates in swiftlang/swift#38167 , the driver is no longer passing -Xllvm -sil-print-debuginfo if -g is given.

@swift-ci test