[llvm] [LV] Ignore some costs when loop gets fully unrolled (PR #106699)

[Florian Hahn via llvm-commits]

================
@@ -7224,6 +7259,14 @@ LoopVectorizationPlanner::precomputeCosts(VPlan &Plan, ElementCount VF,
         continue;
       IVInsts.push_back(CI);
     }
+
+    // If with the given VF loop gets fully unrolled, ignore the costs of
+    // comparison and induction instructions, as they'll get simplified away
----------------
fhahn wrote:

```suggestion
    // comparison and induction instructions, as they'll get simplified away.
```

https://github.com/llvm/llvm-project/pull/106699