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

[Sander de Smalen via llvm-commits]

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@@ -443,6 +443,9 @@ AArch64RegisterInfo::getStrictlyReservedRegs(const MachineFunction &MF) const {
       Reserved.set(SubReg);
   }
 
+  // VG cannot be allocated
+  Reserved.set(AArch64::VG);
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sdesmalen-arm wrote:

I'm not sure it really matters. None of the tests fail so it seems valid to just mark it as reserved, even if it's not used when functions are not compiled for SVE or SME.

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