[llvm] Add freeze for LowerSELECT (PR #148796)

[Simon Pilgrim via llvm-commits]

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@@ -10099,6 +10099,15 @@ define <2 x i64> @srem_zero_zero() {
 ; GCN-LABEL: kernel:
 ; GCN:       ; %bb.0: ; %entry
 ; GCN-NEXT:    s_endpgm
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RKSimon wrote:

redundant check?

https://github.com/llvm/llvm-project/pull/148796