[llvm] [LoopVectorize] Add the cost of VPInstruction::AnyOf to vplan (PR #125058)

[David Sherwood via llvm-commits]

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@@ -7539,7 +7539,7 @@ VectorizationFactor LoopVectorizationPlanner::computeBestVF() {
                         CM.CostKind);
   precomputeCosts(BestPlan, BestFactor.Width, CostCtx);
   assert((BestFactor.Width == LegacyVF.Width ||
-          Legal->hasUncountableEarlyExit() ||
+          BestPlan.hasRegionWithEarlyExit() ||
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david-arm wrote:

Yeah, I struggled with naming too. There is only one exiting block that just happens to have the conditions merged and there is only a single successor - the middle split block. What most accurately describes the CFG is something like:

`doesRegionTerminatorHaveMultipleConditionsForExiting`

or

`isMiddleBlockIndirectSuccessorOfVectorRegion`

but these seem a bit wordy! I'm happy to inline the check here for now, however I imagine at some point it will be useful to have some way of querying this.

https://github.com/llvm/llvm-project/pull/125058