[llvm] [SLP]Exclude non-profitable subtrees. (PR #162018)

[Alexey Bataev via llvm-commits]

alexey-bataev wrote:

> > I see failures like
> > ```
> > Instruction does not dominate all uses!
> >   %21 = insertelement <12 x i32> %20, i32 %call312, i64 7, !dbg !32
> >   %12 = shufflevector <12 x i32> %21, <12 x i32> poison, <8 x i32> <i32 4, i32 1, i32 2, i32 7, i32 poison, i32 poison, i32 poison, i32 poison>, !dbg !32
> > in function test_diff_18
> > fatal error: error in backend: Broken function found, compilation aborted!
> > ```
> > 
> > 
> >     
> >       
> >     
> > 
> >       
> >     
> > 
> >     
> >   
> > with this patch, also with the recommit in [1a8f5fa](https://github.com/llvm/llvm-project/commit/1a8f5fa823a55bce9be368097d2ac7e137fe5d17).
> > I don't have a reproducer I can share yet but I'll try to extract something.
> 
> @alexey-bataev `opt -passes="slp-vectorizer,verify" bbi-113847.ll -S -o -` [bbi-113847.ll.gz](https://github.com/user-attachments/files/24393293/bbi-113847.ll.gz)

Fixed in 27cf32dafdcf08095540d825a2c7ab9e43bdaa69

https://github.com/llvm/llvm-project/pull/162018