[llvm] [VPlan] Dispatch to multiple exit blocks via middle blocks. (PR #112138)

[Florian Hahn via llvm-commits]

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@@ -9238,11 +9259,25 @@ LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(VFRange &Range) {
          "VPBasicBlock");
   RecipeBuilder.fixHeaderPhis();
 
+  if (Legal->hasUncountableEarlyExit()) {
+    assert(Legal->getUncountableExitingBlocks().size() == 1 &&
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fhahn wrote:

Updated, it required updating `getUncountableEarlyExitingBlock` to return nullptr in if `!UncountableEarlyExit` and some slight adjustments on how it is set (and clear the entries if it is false).

WDYT @david-arm ?

https://github.com/llvm/llvm-project/pull/112138