[llvm] [SLP]Transform stores + reverse to strided stores with stride -1, if profitable. (PR #90464)

[Alexey Bataev via llvm-commits]

alexey-bataev wrote:

> Hi @alexey-bataev.
> 
> I'm confused by the code generation of this GCC torture test after this change:
> 
> https://www.godbolt.org/z/frnz9K1n4
> 
> Check line 5. I would expect the pointer of a negative strided store be moved at the address of the last element of the store. Instead we store at the original place (i.e. I'd expect something like `addi a2, a0, 4` and then `vsse32.v v8, (a2), a1`)

Yes, looks like you're right, forgot to take the last pointer. Will fix it ASAP.

https://github.com/llvm/llvm-project/pull/90464