[llvm] [VPlan] Enable vectorization of early-exit loops with unit-stride fault-only-first loads (PR #151300)

[Shih-Po Hung via llvm-commits]

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@@ -107,6 +108,7 @@ bool VPRecipeBase::mayReadFromMemory() const {
     return cast<VPInstruction>(this)->opcodeMayReadOrWriteFromMemory();
   case VPWidenLoadEVLSC:
   case VPWidenLoadSC:
+  case VPWidenFFLoadSC:
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arcbbb wrote:

I lean toward treating VPWidenFFLoad as side‑effecting since it returns vector length, similar to VPInstruction::ExplicitVectorLength.

https://github.com/llvm/llvm-project/pull/151300