[llvm] Spill/restore FP/BP around instructions in which they are clobbered (PR #81048)

[via llvm-commits]

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@@ -963,6 +963,16 @@ class TargetRegisterInfo : public MCRegisterInfo {
     return false;
   }
 
+  /// Returns true if the target needs a base register.
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weiguozhi wrote:

Simply implements requiresVirtualBaseRegisters and returns true for X86 doesn't work, it still generates wrong code for i386-baseptr.ll. It needs more changes in different places.

https://github.com/llvm/llvm-project/pull/81048