[clang] [llvm] [HIP][MacOS] Mach-O support and Darwin toolchain fixes (PR #183991)

[Paulius Velesko via llvm-commits]

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@@ -121,13 +123,26 @@ offloading::getOffloadEntryArray(Module &M, StringRef SectionName) {
   auto Linkage = Triple.isOSBinFormatCOFF() ? GlobalValue::WeakODRLinkage
                                             : GlobalValue::ExternalLinkage;
 
+  // Mach-O uses linker-defined section boundary symbols with a special naming
+  // convention: \1section$start$<segment>$<section> (the \1 prefix suppresses
+  // the leading underscore that Mach-O normally adds to C symbols).
+  std::string MachOSection = "__LLVM,offload_entries";
+  std::string StartName, StopName;
+  if (Triple.isOSBinFormatMachO()) {
+    StartName = "\1section$start$__LLVM$offload_entries";
+    StopName = "\1section$end$__LLVM$offload_entries";
+  } else {
+    StartName = ("__start_" + SectionName).str();
+    StopName = ("__stop_" + SectionName).str();
+  }
+
   auto *EntriesB =
       new GlobalVariable(M, EntryType, /*isConstant=*/true, Linkage, EntryInit,
-                         "__start_" + SectionName);
+                         StartName);
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pvelesko wrote:

Added helper `getOffloadEntrySection` 

https://github.com/llvm/llvm-project/pull/183991