[llvm] [nfc][InstrFDO]Encapsulate header writes in a class member function (PR #90142)

[Mingming Liu via llvm-commits]

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@@ -763,16 +771,25 @@ Error InstrProfWriter::writeImpl(ProfOStream &OS) {
   }
   InfoObj->CSSummaryBuilder = nullptr;
 
+  const size_t MemProfOffset =
+      BackPatchStartOffset + sizeof(IndexedInstrProf::Header::HashOffset);
+  const size_t BinaryIdOffset =
+      MemProfOffset + sizeof(IndexedInstrProf::Header::MemProfOffset);
+  const size_t TemporalProfTracesOffset =
+      BinaryIdOffset + sizeof(IndexedInstrProf::Header::BinaryIdOffset);
+  const size_t VTableNamesOffset =
+      TemporalProfTracesOffset +
+      sizeof(IndexedInstrProf::Header::TemporalProfTracesOffset);
   if (!WritePrevVersion) {
     // Now do the final patch:
     PatchItem PatchItems[] = {
         // Patch the Header.HashOffset field.
-        {HashTableStartFieldOffset, &HashTableStart, 1},
+        {BackPatchStartOffset, &HashTableStart, 1},
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minglotus-6 wrote:

I updated the code to use `sizeof(uint64_t)`



https://github.com/llvm/llvm-project/pull/90142