[llvm] [AArch64][GlobalISel] Correct instructions for 64bit fneg constant vectors. (PR #166537)

[Sjoerd Meijer via llvm-commits]

https://github.com/sjoerdmeijer approved this pull request.

Looks like a good and straight forward fix to me, but I haven't reviewed GISel code before, so maybe we can get a second opinion before merging this.

Just a question: I think this is fixing https://github.com/llvm/llvm-project/issues/166400, but isn't mentioned in the description. Do you expect some more work before that can be closed?

https://github.com/llvm/llvm-project/pull/166537