[llvm] [AArch64][CostModel] Consider the cost of const vector (PR #117539)

[Alexey Bataev via llvm-commits]

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@@ -11019,8 +11039,6 @@ BoUpSLP::getEntryCost(const TreeEntry *E, ArrayRef<Value *> VectorizedVals,
 
   bool NeedToShuffleReuses = !E->ReuseShuffleIndices.empty();
   if (E->isGather()) {
-    if (allConstant(VL))
-      return 0;
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alexey-bataev wrote:

1. I do not see any kind of "complexity" in your constants analysis. OperandValueInfo already contains most of the stuff required. If you need some extra stuff, expand OperandValueInfo/Operands info.
2. Adding a call here introduces an extra divergence point, which complicates things.  

https://github.com/llvm/llvm-project/pull/117539