[llvm] [DAG] isKnownNeverZero - add ISD::SRA/SRL DemandedElts handling and tests (PR #183577)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,32 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc  -mtriple=aarch64-linux-gnu < %s | FileCheck %s
+
+define i1 at srl_neverzero(<4 x i32> %v){
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RKSimon wrote:

(style) 
```suggestion
define i1 @srl_neverzero(<4 x i32> %v) {
```
same for others

https://github.com/llvm/llvm-project/pull/183577