[SubZero] Implement address optimization for MIPS

src/IceTargetLoweringMIPS32.h

Index: src/IceTargetLoweringMIPS32.h
diff --git a/src/IceTargetLoweringMIPS32.h b/src/IceTargetLoweringMIPS32.h
index b555b9bcf6ae62b5afca1f6b00bc24b3921b5350..58ce642c2c3b8ed026a5809f186b58b52512abc4 100644
--- a/src/IceTargetLoweringMIPS32.h
+++ b/src/IceTargetLoweringMIPS32.h
@@ -626,6 +626,9 @@ protected:
 private:
   ENABLE_MAKE_UNIQUE;
 
+  OperandMIPS32Mem *formAddressingMode(Type Ty, Cfg *Func, const Inst *LdSt,
+                                       Operand *Base);
+
   class ComputationTracker {
   public:
     ComputationTracker() = default;