[PATCH] D114457: [z/OS] Implement prologue and epilogue generation for z/OS target.

[Ulrich Weigand via Phabricator via llvm-commits]

uweigand added inline comments.


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Comment at: llvm/lib/Target/SystemZ/SystemZCallingConv.td:169
 def CSR_SystemZ_XPLINK64 : CalleeSavedRegs<(add (sequence "R%dD", 7, 15),
+                                                (sequence "R%dD", 4, 4),
                                                 (sequence "F%dD", 15, 8))>;
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I'm wondering if it wouldn't be more straightforward to handle this in determineCalleeSaves, in the place where the frame pointer register is handled?


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Comment at: llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp:1055
+uint64_t SystemZXPLINKFrameLowering::getAllocatedStackSize(
+    const MachineFunction &MF) const {
+
----------------
This is no longer called anywhere and should be deleted.


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Comment at: llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp:1180
+
+StackOffset SystemZXPLINKFrameLowering::getFrameIndexReference(
+    const MachineFunction &MF, int FI, Register &FrameReg) const {
----------------
This function is now actually identical to the default implementation and should also be deleted.


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Comment at: llvm/lib/Target/SystemZ/SystemZISelLowering.cpp:1504
+      int64_t ArgSPOffset = VA.getLocMemOffset(); 
+      if (Subtarget.isTargetXPLINK64()) {
+        auto &XPRegs = Subtarget.getSpecialRegisters<SystemZXPLINK64Registers>();
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It's a bit ugly, but I'd be OK with it for now.  It would be good to add a FIXME saying that ideally the call frame size should have already been included in the offset.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D114457/new/

https://reviews.llvm.org/D114457