Stop relying on `cl::opt` to pass along the driver's decision to
preserve use-lists. Create a new `-cc1` option called
`-emit-llvm-uselists` that does the right thing (when -emit-llvm-bc).
Note that despite its generic name, it *doesn't* do the right thing when
-emit-llvm (LLVM assembly) yet. I'll hook that up soon.
This doesn't really change the behaviour of the driver. The default is
still to preserve use-lists for `clang -emit-llvm` and `clang
-save-temps`, and nothing else. But it stops relying on global state
(and also is a nicer interface for hackers using `clang -cc1`).
llvm-svn: 234962
Change `clang` to set `-preserve-bc-uselistorder` for the driver options
`-emit-llvm` and `-save-temps`. The former is useful for reproducing
results from `clang` in `opt` or `llc`, while the latter prevents
`-save-temps` from affecting the output. This is part of PR5680.
`-preserve-bc-uselistorder=true` is currently on by default, but a
follow-up commit in LLVM will reverse it.
llvm-svn: 234920