[llvm] [VPlan] Simplify reverses through unary ops (fneg) (PR #208257)

[via llvm-commits]

github-actions[bot] wrote:

test-suite diff from c0ef9c53ecca5f033dc6a022da2a986f6925c70e...c78abc4acdd2986985674d5ede356b241206fe29: https://github.com/llvm/llvm-project/actions/runs/29011583053/artifacts/8197784756

Statistics: https://github.com/llvm/llvm-project/actions/runs/29011583053/artifacts/8197785323

## riscv64-linux-gnu `-march=rva23u64 -O3`
| ('Program', '')    |   ('size..text', 'base') |   ('size..text', 'head') |   ('size..text', 'diff') |
|:-------------------|-------------------------:|-------------------------:|-------------------------:|
| Geomean difference |                      nan |                      nan |                        0 |
## aarch64-linux-gnu `-march=armv9-a -O3`
| ('Program', '')    |   ('size..text', 'base') |   ('size..text', 'head') |   ('size..text', 'diff') |
|:-------------------|-------------------------:|-------------------------:|-------------------------:|
| Geomean difference |                      nan |                      nan |                        0 |
## x86_64-linux-gnu `-march=x86-64-v3 -O3`
| ('Program', '')    |   ('size..text', 'base') |   ('size..text', 'head') |   ('size..text', 'diff') |
|:-------------------|-------------------------:|-------------------------:|-------------------------:|
| Geomean difference |                      nan |                      nan |                        0 |


https://github.com/llvm/llvm-project/pull/208257