[llvm-branch-commits] [llvm] Use register pair for PC spill (PR #169098)

[Matt Arsenault via llvm-branch-commits]

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@@ -267,11 +267,19 @@ bool SILowerSGPRSpills::spillCalleeSavedRegs(
 
     std::vector<CalleeSavedInfo> CSI;
     const MCPhysReg *CSRegs = MRI.getCalleeSavedRegs();
+    Register RetAddrReg = TRI->getReturnAddressReg(MF);
+    bool SpillRetAddrReg = false;
 
     for (unsigned I = 0; CSRegs[I]; ++I) {
       MCRegister Reg = CSRegs[I];
 
       if (SavedRegs.test(Reg)) {
+        if (Reg == TRI->getSubReg(RetAddrReg, AMDGPU::sub0) ||
+            Reg == TRI->getSubReg(RetAddrReg, AMDGPU::sub1)) {
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arsenm wrote:

Pull the getSubRegs out of the loop 

https://github.com/llvm/llvm-project/pull/169098