[llvm] [MC][DWARF][NFC] Drop CIEKey map (PR #96075)

[Fangrui Song via llvm-commits]

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@@ -1777,23 +1777,7 @@ void FrameEmitterImpl::EmitFDE(const MCSymbol &cieStart,
 namespace {
 
 struct CIEKey {
-  static const CIEKey getEmptyKey() {
-    return CIEKey(nullptr, 0, -1, false, false, static_cast<unsigned>(INT_MAX),
-                  false, false);
-  }
-
-  static const CIEKey getTombstoneKey() {
-    return CIEKey(nullptr, -1, 0, false, false, static_cast<unsigned>(INT_MAX),
-                  false, false);
-  }
-
-  CIEKey(const MCSymbol *Personality, unsigned PersonalityEncoding,
-         unsigned LSDAEncoding, bool IsSignalFrame, bool IsSimple,
-         unsigned RAReg, bool IsBKeyFrame, bool IsMTETaggedFrame)
-      : Personality(Personality), PersonalityEncoding(PersonalityEncoding),
-        LsdaEncoding(LSDAEncoding), IsSignalFrame(IsSignalFrame),
-        IsSimple(IsSimple), RAReg(RAReg), IsBKeyFrame(IsBKeyFrame),
-        IsMTETaggedFrame(IsMTETaggedFrame) {}
+  CIEKey() {}
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MaskRay wrote:

`= default`

https://github.com/llvm/llvm-project/pull/96075