[llvm] [RISCV] Support PreserveMost calling convention (PR #148214)

[Craig Topper via llvm-commits]

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@@ -68,6 +68,8 @@ RISCVRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
   auto &Subtarget = MF->getSubtarget<RISCVSubtarget>();
   if (MF->getFunction().getCallingConv() == CallingConv::GHC)
     return CSR_NoRegs_SaveList;
+  if (MF->getFunction().getCallingConv() == CallingConv::PreserveMost)
+    return CSR_RT_MostRegs_SaveList;
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topperc wrote:

Do we need to consider RVE here?

https://github.com/llvm/llvm-project/pull/148214