[llvm] [yaml2obj][XOFF] Update yaml2obj for XCOFF to create valid XCOFF files in more cases. (PR #77620)

[James Henderson via llvm-commits]

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@@ -320,30 +361,32 @@ void XCOFFWriter::initAuxFileHeader() {
 }
 
 bool XCOFFWriter::assignAddressesAndIndices() {
-  uint64_t FileHdrSize =
+  const uint64_t FileHdrSize =
       Is64Bit ? XCOFF::FileHeaderSize64 : XCOFF::FileHeaderSize32;
-  uint64_t AuxFileHdrSize = 0;
-  if (Obj.AuxHeader)
-    AuxFileHdrSize = Obj.Header.AuxHeaderSize
-                         ? Obj.Header.AuxHeaderSize
-                         : (Is64Bit ? XCOFF::AuxFileHeaderSize64
-                                    : XCOFF::AuxFileHeaderSize32);
-  uint64_t SecHdrSize =
+
+  // If AuxHeaderSize is specified in the YAML file, we construct
+  // an auxiliary header.
+  const uint64_t AuxFileHdrSize =
+      Obj.Header.AuxHeaderSize ? *Obj.Header.AuxHeaderSize
+      : !Obj.AuxHeader
+          ? 0
+          : (Is64Bit ? XCOFF::AuxFileHeaderSize64 : XCOFF::AuxFileHeaderSize32);
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jh7370 wrote:

This code is now less readable than before. It's not necessary to use `const` everywhere, so go back to the old style, please.

https://github.com/llvm/llvm-project/pull/77620