[llvm] [X86][CodeGen] Teach frame lowering to spill/reload registers w/ PUSHP/POPP, PUSH2[P]/POP2[P] (PR #73292)

[Phoebe Wang via llvm-commits]

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@@ -2958,15 +3066,30 @@ bool X86FrameLowering::restoreCalleeSavedRegisters(
   }
 
   // POP GPRs.
-  unsigned Opc = STI.is64Bit() ? X86::POP64r : X86::POP32r;
+  MachineInstrBuilder MIB;
+  bool IncompletePop2 = false;
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phoebewang wrote:

Maybe use the iterator for CST and increase one more time for Push2Pop2?

https://github.com/llvm/llvm-project/pull/73292