[llvm] [LoopVectorize] Add support for vectorisation of simple early exit loops (PR #88385)

[Shih-Po Hung via llvm-commits]

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@@ -2831,6 +2840,18 @@ class VPRegionBlock : public VPBlockBase {
   /// VPRegionBlock.
   VPBlockBase *Exiting;
 
+  /// Hold the Early Exiting block of the SEME region, if one exists.
+  VPBlockBase *EarlyExit;
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arcbbb wrote:

IIUC, for the SEME region, the latch exit VPBlock `middle.block` is placed as the successor of the region block, and the other exit VPBlocks other than the latch exit VPBlock are included in the region block, e.g. `vector.early.exit` pointed by `EarlyExit`.
And the early exiting block would be the predecessor of `EarlyExit`. 
Therefore the comment should be updated to `/// Hold the Early Exit block of the SEME region, if one exists`.

https://github.com/llvm/llvm-project/pull/88385