[PATCH] D39636: [X86] Don't clobber reserved registers with stack adjustments

[Reid Kleckner via Phabricator via llvm-commits]

rnk accepted this revision.
rnk added a comment.
This revision is now accepted and ready to land.

Marking accepted in the review tool.

In https://reviews.llvm.org/D39636#917117, @mkuper wrote:

> I'm not sure whether it's the right fix.
>  I would expect the clobbers list of an instruction to be precise - if it says it's clobbered, you can't rely on it being preserved across the call, whatever the circumstances. So maybe the right thing to do would be to filter reserved registers out of the clobber list for these invokes when they're lowered?
>
> @rnk, thoughts?


Maybe SP is a special case, but CALL is definitely a def of SP, and we don't worry about it's liveness or preservation because it's reserved.


https://reviews.llvm.org/D39636