[llvm] [VPlan] Replace ExtractFromEnd with Extract(Last|Penultimate)Lane (NFC). (PR #137030)

[via llvm-commits]

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@@ -337,16 +337,18 @@ void UnrollState::unrollBlock(VPBlockBase *VPB) {
       continue;
     }
     VPValue *Op0;
-    if (match(&R, m_VPInstruction<VPInstruction::ExtractFromEnd>(
-                      m_VPValue(Op0), m_VPValue(Op1)))) {
+    if (match(&R, m_VPInstruction<VPInstruction::ExtractLastElement>(
+                      m_VPValue(Op0))) ||
+        match(&R, m_VPInstruction<VPInstruction::ExtractPenultimateElement>(
+                      m_VPValue(Op0)))) {
       addUniformForAllParts(cast<VPSingleDefRecipe>(&R));
       if (Plan.hasScalarVFOnly()) {
-        // Extracting from end with VF = 1 implies retrieving the scalar part UF
-        // - Op1.
+        auto *I = cast<VPInstruction>(&R);
+        // Extracting from end with VF = 1 implies retrieving retrieving the
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ayalz wrote:

```suggestion
        // Extracting from end with VF = 1 implies retrieving the
```


https://github.com/llvm/llvm-project/pull/137030