[llvm] [z/OS][GOFF] Implement support for writing ESD + TXT records by the GOFFObjectWriter (PR #85851)

[Ulrich Weigand via llvm-commits]

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@@ -259,6 +633,411 @@ void GOFFObjectWriter::writeHeader() {
   OS.write_zeros(6);       // Reserved
 }
 
+void GOFFObjectWriter::writeSymbol(const GOFFSymbol &Symbol,
+                                   const MCAsmLayout &Layout) {
+  uint32_t Offset = 0;
+  uint32_t Length = 0;
+  GOFF::ESDNameSpaceId NameSpaceId = GOFF::ESD_NS_ProgramManagementBinder;
+  Flags SymbolFlags;
+  uint8_t FillByteValue = 0;
+
+  Flags BehavAttrs[10] = {};
+  auto setAmode = [&BehavAttrs](GOFF::ESDAmode Amode) {
+    BehavAttrs[0].set(0, 8, Amode);
+  };
+  auto setRmode = [&BehavAttrs](GOFF::ESDRmode Rmode) {
+    BehavAttrs[1].set(0, 8, Rmode);
+  };
+  auto setTextStyle = [&BehavAttrs](GOFF::ESDTextStyle Style) {
+    BehavAttrs[2].set(0, 4, Style);
+  };
+  auto setBindingAlgorithm =
+      [&BehavAttrs](GOFF::ESDBindingAlgorithm Algorithm) {
+        BehavAttrs[2].set(4, 4, Algorithm);
+      };
+  auto setTaskingBehavior =
+      [&BehavAttrs](GOFF::ESDTaskingBehavior TaskingBehavior) {
+        BehavAttrs[3].set(0, 3, TaskingBehavior);
+      };
+  auto setReadOnly = [&BehavAttrs](bool ReadOnly) {
+    BehavAttrs[3].set(4, 1, ReadOnly);
+  };
+  auto setExecutable = [&BehavAttrs](GOFF::ESDExecutable Executable) {
+    BehavAttrs[3].set(5, 3, Executable);
+  };
+  auto setDuplicateSeverity =
+      [&BehavAttrs](GOFF::ESDDuplicateSymbolSeverity DSS) {
+        BehavAttrs[4].set(2, 2, DSS);
+      };
+  auto setBindingStrength = [&BehavAttrs](GOFF::ESDBindingStrength Strength) {
+    BehavAttrs[4].set(4, 4, Strength);
+  };
+  auto setLoadingBehavior = [&BehavAttrs](GOFF::ESDLoadingBehavior Behavior) {
+    BehavAttrs[5].set(0, 2, Behavior);
+  };
+  auto setIndirectReference = [&BehavAttrs](bool Indirect) {
+    uint8_t Value = Indirect ? 1 : 0;
+    BehavAttrs[5].set(3, 1, Value);
+  };
+  auto setBindingScope = [&BehavAttrs](GOFF::ESDBindingScope Scope) {
+    BehavAttrs[5].set(4, 4, Scope);
+  };
+  auto setLinkageType = [&BehavAttrs](GOFF::ESDLinkageType Type) {
+    BehavAttrs[6].set(2, 1, Type);
+  };
+  auto setAlignment = [&BehavAttrs](GOFF::ESDAlignment Alignment) {
+    BehavAttrs[6].set(3, 5, Alignment);
+  };
+
+  uint32_t AdaEsdId = 0;
+  uint32_t SortPriority = 0;
+
+  switch (Symbol.SymbolType) {
----------------
uweigand wrote:

This whole logic that only *some* bits of information from the overall `GOFFSymbol` are used based on its type is confusing.  As mentioned above, it would then be better to have type-specific constructors that ensure that all (and *only*) those bits needed for this particular type are actually provided.

https://github.com/llvm/llvm-project/pull/85851