[llvm] [AArch64] Re-enable rematerialization for streaming-mode-changing functions. (PR #83235)

[Paul Walker via llvm-commits]

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@@ -9494,40 +9494,12 @@ bool AArch64InstrInfo::isReallyTriviallyReMaterializable(
     // Avoid rematerializing rematerializable instructions that use/define
     // scalable values, such as 'pfalse' or 'ptrue', which result in different
     // results when the runtime vector length is different.
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paulwalker-arm wrote:

This comment likely needs updating?

https://github.com/llvm/llvm-project/pull/83235