[clang] [llvm] [SystemZ] Global Stackprotector and associated location section (PR #169317)

[Dominik Steenken via cfe-commits]

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@@ -1805,15 +1777,141 @@ bool SystemZInstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
     splitAdjDynAlloc(MI);
     return true;
 
-  case TargetOpcode::LOAD_STACK_GUARD:
-    expandLoadStackGuard(&MI);
+  case SystemZ::MOVE_STACK_GUARD:
+    expandMSGPseudo(MI);
+    return true;
+
+  case SystemZ::COMPARE_STACK_GUARD:
+    expandCSGPseudo(MI);
     return true;
 
   default:
     return false;
   }
 }
 
+namespace {
+Register scavengeAddrReg(MachineInstr &MI, MachineBasicBlock *MBB) {
+  // create fresh RegScavanger instance.
+  RegScavenger RS;
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dominik-steenken wrote:

This is really only meant to be a workaround until issue https://github.com/llvm/llvm-project/issues/172511 is fixed. Given that, is doing it properly here still worthwhile? Once the issue is fixed, this whole function will have to be deleted, as will any work i would have done to properly maintain a RegScavenger instance in the PostRA Pseudo Expander.

https://github.com/llvm/llvm-project/pull/169317