[clang] [NFC] [Serializer] Pack information in serializer (PR #69287)

[Chuanqi Xu via cfe-commits]

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@@ -2005,14 +2039,11 @@ void ASTWriter::WriteDeclAbbrevs() {
   // Decl
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
-  Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
-  Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
-  Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
-  Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
-  Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
-  Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));  // ModuleOwnershipKind
+  Abv->Add(BitCodeAbbrevOp(
+      BitCodeAbbrevOp::Fixed,
+      11)); // Packed DeclBits: isInvalidDecl, HasAttrs, isImplicit, isUsed,
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ChuanqiXu9 wrote:

This looks odd at the first sight. But it is formatted by clang-format. And it looks not bad after looking into it.

https://github.com/llvm/llvm-project/pull/69287