[llvm] [XCOFF][obj2yaml] support parsing auxiliary symbols for XCOFF (PR #70642)

[James Henderson via llvm-commits]

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@@ -131,7 +200,121 @@ Error XCOFFDumper::dumpSymbols() {
 
     Sym.Type = SymbolEntRef.getSymbolType();
     Sym.StorageClass = SymbolEntRef.getStorageClass();
-    Sym.NumberOfAuxEntries = SymbolEntRef.getNumberOfAuxEntries();
+    uint8_t NumOfAuxSym = SymbolEntRef.getNumberOfAuxEntries();
+    Sym.NumberOfAuxEntries = NumOfAuxSym;
+
+    if (NumOfAuxSym) {
+      auto AuxEntTbl = &Sym.AuxEntries;
+      switch (Sym.StorageClass) {
+      case XCOFF::C_FILE: {
+        for (int I = 1; I <= NumOfAuxSym; I++) {
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jh7370 wrote:

1) `NumOfAuxSym` is a `uint8_t`, so `I` should be too.
2) `++I` (https://llvm.org/docs/CodingStandards.html#prefer-preincrement)

Also, this bit of code is pretty substantial. Let's pull this case body into a separate function for ease of following the `switch`.

https://github.com/llvm/llvm-project/pull/70642