[llvm] [LoopVectorize] Teach LoopVectorizationLegality about more early exits (PR #107004)

[Paul Walker via llvm-commits]

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@@ -1070,6 +1070,50 @@ bool LoopVectorizationLegality::canVectorizeMemory() {
     return false;
   }
 
+  // For loops with uncountable early exiting blocks that are not the latch
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paulwalker-arm wrote:

"that are not the latch" can be dropped because by definition the latch block cannot be early exiting?

https://github.com/llvm/llvm-project/pull/107004