[llvm] [TRI] Remove reserved registers in getRegPressureSetLimit (PR #118787)

[Matt Arsenault via llvm-commits]

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@@ -674,6 +674,50 @@ TargetRegisterInfo::prependOffsetExpression(const DIExpression *Expr,
                                       PrependFlags & DIExpression::EntryValue);
 }
 
+unsigned TargetRegisterInfo::getRegPressureSetLimit(const MachineFunction &MF,
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arsenm wrote:

It's still desirable to cache this somewhere (which I guess was the point of RegisterClassInfo). Computing this is very much not cheap. Is there a way to try to push users to go through RegisterClassInfo?

https://github.com/llvm/llvm-project/pull/118787