[llvm] [llvm-nm][GOFF] Display archive attributes in GOFF archives through --print-armap (PR #214527)

[James Henderson via llvm-commits]

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@@ -2045,9 +2045,40 @@ static bool checkMachOAndArchFlags(SymbolicFile *O, StringRef Filename) {
   return true;
 }
 
-static void printArchiveMap(iterator_range<Archive::symbol_iterator> &map,
-                            StringRef Filename) {
-  for (auto I : map) {
+/// Decode the low 3 bits of a z/OS archive symbol attribute word into a
+/// human-readable string, e.g. "[64-bit + XPLink]".
+/// Any bits above the known 3-bit mask produce a trailing "?" flag.
+static std::string decodeZOSAttributes(uint32_t Attrs) {
+  bool Unknown = (Attrs & ~Archive::Symbol::ZOSKnownAttrMask) != 0;
+  bool Is64Bit = (Attrs & Archive::Symbol::ZOSAttr64Bit) != 0;
+  bool IsXPLink = (Attrs & Archive::Symbol::ZOSAttrXPLink) != 0;
+  bool IsWSA = (Attrs & Archive::Symbol::ZOSAttrWSA) != 0;
+
+  std::string Result = "[";
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jh7370 wrote:

Rather than create a local `std::string` that is repeatedly modified (causing additional memory allocations etc), pass in the output stream you are writing to and stream to that directly.

https://github.com/llvm/llvm-project/pull/214527