[RISCV][NFC] Rename callee saved regs 'CSR' to CSR_ILP32_LP64 and minor RISCVRegisterInfo refactoring

The CSR renaming further prepares the way for an upcoming patch adding support for more
RISC-V ABIs.

Modify RISCVRegisterInfo::getCalleeSavedRegs and
RISCVRegisterInfo::getReservedRegs to do MF->getSubtarget<RISCVSubtarget>()
once rather than multiple times.

llvm-svn: 356123

1 files changed, 8 insertions, 6 deletions

diff --git a/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp b/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
index 38af3827e4c..0beb166ec00 100644
--- a/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
+++ b/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
@@ -32,14 +32,15 @@ RISCVRegisterInfo::RISCVRegisterInfo(unsigned HwMode)
 
 const MCPhysReg *
 RISCVRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
+  auto &Subtarget = MF->getSubtarget<RISCVSubtarget>();
   if (MF->getFunction().hasFnAttribute("interrupt")) {
-    if (MF->getSubtarget<RISCVSubtarget>().hasStdExtD())
+    if (Subtarget.hasStdExtD())
       return CSR_XLEN_F64_Interrupt_SaveList;
-    if (MF->getSubtarget<RISCVSubtarget>().hasStdExtF())
+    if (Subtarget..hasStdExtF())
       return CSR_XLEN_F32_Interrupt_SaveList;
     return CSR_Interrupt_SaveList;
   }
-  return CSR_SaveList;
+  return CSR_ILP32_LP64_SaveList;
 }
 
 BitVector RISCVRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
@@ -118,12 +119,13 @@ unsigned RISCVRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
 const uint32_t *
 RISCVRegisterInfo::getCallPreservedMask(const MachineFunction & MF,
                                         CallingConv::ID /*CC*/) const {
+  auto &Subtarget = MF->getSubtarget<RISCVSubtarget>();
   if (MF.getFunction().hasFnAttribute("interrupt")) {
-    if (MF.getSubtarget<RISCVSubtarget>().hasStdExtD())
+    if (Subtarget.hasStdExtD())
       return CSR_XLEN_F64_Interrupt_RegMask;
-    if (MF.getSubtarget<RISCVSubtarget>().hasStdExtF())
+    if (Subtarget.hasStdExtF())
       return CSR_XLEN_F32_Interrupt_RegMask;
     return CSR_Interrupt_RegMask;
   }
-  return CSR_RegMask;
+  return CSR_ILP32_LP64_RegMask;
 }