[llvm] [SystemZ][z/OS] TXT records in the GOFF reader (PR #74526)

[James Henderson via llvm-commits]

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@@ -394,6 +406,161 @@ GOFFObjectFile::getSectionPrEsdRecord(uint32_t SectionIndex) const {
   return EsdRecord;
 }
 
+uint32_t GOFFObjectFile::getSectionDefEsdId(DataRefImpl &Sec) const {
+  const uint8_t *EsdRecord = getSectionEdEsdRecord(Sec);
+  uint32_t Length;
+  ESDRecord::getLength(EsdRecord, Length);
+  if (Length == 0) {
+    const uint8_t *PrEsdRecord = getSectionPrEsdRecord(Sec);
+    if (PrEsdRecord)
+      EsdRecord = PrEsdRecord;
+  }
+
+  uint32_t DefEsdId;
+  ESDRecord::getEsdId(EsdRecord, DefEsdId);
+  LLVM_DEBUG(dbgs() << "Got def EsdId: " << DefEsdId << '\n');
+  return DefEsdId;
+}
+
+void GOFFObjectFile::moveSectionNext(DataRefImpl &Sec) const {
+  Sec.d.a++;
+  if ((Sec.d.a) >= SectionList.size())
+    Sec.d.a = 0;
+}
+
+Expected<StringRef> GOFFObjectFile::getSectionName(DataRefImpl Sec) const {
+  DataRefImpl EdSym;
+  SectionEntryImpl EsdIds = SectionList[Sec.d.a];
+  EdSym.d.a = EsdIds.d.a;
+  Expected<StringRef> Name = getSymbolName(EdSym);
+  if (Name) {
+    StringRef Res = *Name;
+    LLVM_DEBUG(dbgs() << "Got section: " << Res << '\n');
+    // TODO: Make clang look for C____clangast instead of this
+    if (Res.equals("C___clangast"))
+      Res = "__clangast";
+    LLVM_DEBUG(dbgs() << "Final section name: " << Res << '\n');
+    Name = Res;
+  }
+  return Name;
+}
+
+uint64_t GOFFObjectFile::getSectionAddress(DataRefImpl Sec) const {
+  uint32_t Offset;
+  const uint8_t *EsdRecord = getSectionEdEsdRecord(Sec);
+  ESDRecord::getOffset(EsdRecord, Offset);
+  return Offset;
+}
+
+uint64_t GOFFObjectFile::getSectionSize(DataRefImpl Sec) const {
+  uint32_t Length;
+  uint32_t DefEsdId = getSectionDefEsdId(Sec);
+  const uint8_t *EsdRecord = EsdPtrs[DefEsdId];
+  ESDRecord::getLength(EsdRecord, Length);
+  LLVM_DEBUG(dbgs() << "Got section size: " << Length << '\n');
+  return static_cast<uint64_t>(Length);
+}
+
+// Unravel TXT records and expand fill characters to produce
+// a contiguous sequence of bytes
----------------
jh7370 wrote:

```suggestion
// a contiguous sequence of bytes.
```

https://github.com/llvm/llvm-project/pull/74526