Use oversized stack slots on ez80.

Author: jacobly0

llvm/include/llvm/CodeGen/TargetRegisterInfo.h

@@ -277,7 +277,7 @@ class TargetRegisterInfo : public MCRegisterInfo {
 
   /// Return the size in bytes of the stack slot allocated to hold a spilled
   /// copy of a register from class RC.
-  unsigned getSpillSize(const TargetRegisterClass &RC) const {
+  virtual unsigned getSpillSize(const TargetRegisterClass &RC) const {
     return getRegClassInfo(RC).SpillSize / 8;
   }
 

llvm/lib/Target/Z80/Z80RegisterInfo.cpp

@@ -36,6 +36,13 @@ Z80RegisterInfo::Z80RegisterInfo(const Triple &TT)
   StackPtr = Is24Bit ? Z80::SPL : Z80::SPS;
 }
 
+unsigned Z80RegisterInfo::getSpillSize(const TargetRegisterClass &RC) const {
+  unsigned SpillSize = TargetRegisterInfo::getSpillSize(RC);
+  if (Is24Bit && SpillSize == 2)
+    SpillSize = 3;
+  return SpillSize;
+}
+
 const TargetRegisterClass *
 Z80RegisterInfo::getPointerRegClass(const MachineFunction &MF,
                                     unsigned Kind) const {

llvm/lib/Target/Z80/Z80RegisterInfo.h

@@ -34,6 +34,8 @@ class Z80RegisterInfo final : public Z80GenRegisterInfo {
 public:
   Z80RegisterInfo(const Triple &TT);
 
+  unsigned getSpillSize(const TargetRegisterClass &RC) const override;
+
   /// Code Generation virtual methods...
   ///
   bool trackLivenessAfterRegAlloc(const MachineFunction &MF) const override {