[llvm] [llvm-objdump] Fix --source with --macho flag (PR #163810)

[Ryan Mansfield via llvm-commits]

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@@ -7415,18 +7416,24 @@ static void DisassembleMachO(StringRef Filename, MachOObjectFile *MachOOF,
   std::unique_ptr<DIContext> diContext;
   std::unique_ptr<Binary> DSYMBinary;
   std::unique_ptr<MemoryBuffer> DSYMBuf;
-  if (UseDbg) {
-    // If separate DSym file path was specified, parse it as a macho file,
-    // get the sections and supply it to the section name parsing machinery.
-    if (const ObjectFile *DbgObj =
-            getMachODSymObject(MachOOF, Filename, DSYMBinary, DSYMBuf)) {
+  const ObjectFile *DbgObj = MachOOF;
+  if (UseDbg || PrintSource || PrintLines) {
+    // Look for debug info in external dSYM file or embedded in the object.
+    // getMachODSymObject returns MachOOF by default if no external dSYM found.
+    const ObjectFile *DSym =
+        getMachODSymObject(MachOOF, Filename, DSYMBinary, DSYMBuf);
+    if (!DSym)
+      return;
+    DbgObj = DSym;
+    if (UseDbg) {
       // Setup the DIContext
       diContext = DWARFContext::create(*DbgObj);
-    } else {
-      return;
     }
   }
 
+  SourcePrinter SP(DbgObj, TheTarget->getName());
+  LiveElementPrinter LEP(*MRI, *STI);
+
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rjmansfield wrote:

DisassembleMachO can be called here multiple times e.g. different slices of a universal binary. The statics in the lambda might be an issue. I can use a std::optional here to avoid the unnecessary initialization.

https://github.com/llvm/llvm-project/pull/163810