[llvm-branch-commits] [llvm] [SystemZ] Implement ctor/dtor emission via @@SQINIT and .xtor sections (PR #171476)

[Amy Kwan via llvm-branch-commits]

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@@ -1012,6 +1021,59 @@ void SystemZAsmPrinter::emitMachineConstantPoolValue(
   OutStreamer->emitValue(Expr, Size);
 }
 
+// Emit the ctor or dtor list taking into account the init priority.
+void SystemZAsmPrinter::emitXXStructorList(const DataLayout &DL,
+                                           const Constant *List, bool IsCtor) {
+  if (TM.getTargetTriple().isOSBinFormatGOFF())
+    AsmPrinter::emitXXStructorList(DL, List, IsCtor);
+
+  SmallVector<Structor, 8> Structors;
+  preprocessXXStructorList(DL, List, Structors);
+  if (Structors.empty())
+    return;
+
+  const Align Align = llvm::Align(4);
+  const TargetLoweringObjectFile &Obj = getObjFileLowering();
+  for (Structor &S : Structors) {
+    MCSection *OutputSection =
+        (IsCtor ? Obj.getStaticCtorSection(S.Priority, nullptr)
+                : Obj.getStaticDtorSection(S.Priority, nullptr));
+    OutStreamer->switchSection(OutputSection);
+    if (OutStreamer->getCurrentSection() != OutStreamer->getPreviousSection())
+      emitAlignment(Align);
+
+    const MCSectionGOFF *Section =
+        static_cast<const MCSectionGOFF *>(getCurrentSection());
+    uint32_t XtorPriority = Section->getPRAttributes().SortKey;
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amy-kwan wrote:

Good question. It's technically not the same, as in the function above, the `Priority` is the input and it is recalculated as `Prio` prior to going into section with the PR attribute.

If this code sequence is unclear, would it make more sense to move the priority calculation into this function? Unless there are other suggestions?

https://github.com/llvm/llvm-project/pull/171476