[llvm] [ARM] Specifically delineate between different GPRCS2 positions (PR #116716)

[Oliver Stannard via llvm-commits]

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@@ -2128,14 +2148,17 @@ bool ARMFrameLowering::spillCalleeSavedRegisters(
   auto IsDPRCS1 = [&CheckRegArea](unsigned Reg) {
     return CheckRegArea(Reg, SpillArea::DPRCS1);
   };
+  auto IsGPRCS3 = [&CheckRegArea](unsigned Reg) {
+    return CheckRegArea(Reg, SpillArea::GPRCS3);
+  };
 
   // Windows SEH requires the floating-point registers to be pushed between the
   // two blocks of GPRs in some situations. In all other cases, they are pushed
   // below the GPRs.
   if (PushPopSplit == ARMSubtarget::SplitR11WindowsSEH) {
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ostannard wrote:

Can this `if` be removed now that the blocks are always pushed in the same order?

https://github.com/llvm/llvm-project/pull/116716