[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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@@ -7749,6 +7758,12 @@ VPRecipeBuilder::tryToWidenMemory(Instruction *I, ArrayRef<VPValue *> Operands,
     Builder.insert(VectorPtr);
     Ptr = VectorPtr;
   }
+  if (Legal->getSpeculativeLoads().contains(I)) {
+    auto *Load = dyn_cast<LoadInst>(I);
+    return new VPWidenFFLoadRecipe(*Load, Ptr, Mask, VPIRMetadata(*Load, LVer),
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arcbbb wrote:

Updated! After rebasing, this patch supports WidenFFLoad in non–tail-folded mode only. To tail-fold early-exit loops and FFLoad support in the EVL transform will have to be addressed in a separate patch.

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