[llvm] Update the base and index value for masked gather (PR #130920)

[Rohit Aggarwal via llvm-commits]

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@@ -126,6 +126,11 @@ static cl::opt<bool> MulConstantOptimization(
              "SHIFT, LEA, etc."),
     cl::Hidden);
 
+static cl::opt<bool>
+    EnableBaseIndexUpdate("update-baseIndex", cl::init(true),
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rohitaggarwal007 wrote:

I just added this flag for the safety incase any untest usecase occur. So that we can fall back to existing behavior. 
Sure, I will remove the flag.

https://github.com/llvm/llvm-project/pull/130920