[llvm] [llvm][ARM]Add ARM widen strings pass (PR #107120)

[Nashe Mncube via llvm-commits]

nasherm wrote:

My most recent patch addresses the comments.

> Probably worth investigating if we can fit this easily into some pass that's already examining the uses of globals, like GlobalOpt; iterating over the whole module isn't cheap.

I've had a look at GlobalOpt briefly and I  have a few question: if this pass were added wouldn't investigation also include seeing if this improves performance on other targets? I can see restricting the pass to ARM cores but it seems like that would it make it a poor fit for GlobalOpt. Is there something I'm missing?



https://github.com/llvm/llvm-project/pull/107120