[llvm] [SLP]Initial non-power-of-2 (but still whole register) for remaining nodes (PR #113356)

[Simon Pilgrim via llvm-commits]

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@@ -1,19 +1,35 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
 ; RUN: opt -S --passes=slp-vectorizer -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
 
+; FIXME: need to fix/improve cost estimation of many SK_PermuteTwo vector registers to account
+; correctly for poisoned/identity shuffles and only calculate actual shuffles.
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RKSimon wrote:

I'm hoping #117999 should be enough, but I'm looking at improving x86 processShuffleMasks handling for SK_PermuteTwoSrc but I'm not sure when I'll finish work on it.

https://github.com/llvm/llvm-project/pull/113356