[llvm] [LLVM][InstSimplify] Add folds for SVE integer reduction intrinsics. (PR #167519)

[Paul Walker via llvm-commits]

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@@ -183,6 +183,23 @@ bool Constant::isMinSignedValue() const {
   return false;
 }
 
+bool Constant::isMaxSignedValue() const {
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paulwalker-arm wrote:

This is just a clone of isMinSignedValue with `s/Min/Max/`.

https://github.com/llvm/llvm-project/pull/167519