CPU: Fix BGEZAL with rs == ra

src/pse/cpu_core.cpp

@@ -800,15 +800,15 @@ void Core::ExecuteInstruction(Instruction inst)
       // bgez is the inverse of bltz, so simply do ltz and xor the result
       const bool bgez = ConvertToBoolUnchecked(rt & u8(1));
       const bool branch = (static_cast<s32>(ReadReg(inst.i.rs)) < 0) ^ bgez;
-      if (branch)
-      {
-        const bool link = ConvertToBoolUnchecked((rt >> 4) & u8(1));
+
+      // register is still linked even if the branch isn't taken
+      const bool link = (rt & u8(0x1E)) == u8(0x10);
       if (link)
         m_regs.ra = m_regs.npc;
 
+      if (branch)
         Branch(m_regs.pc + (inst.i.imm_sext32() << 2));
     }
-    }
     break;
 
     case InstructionOp::cop0:

src/pse/cpu_types.h

@@ -214,10 +214,10 @@ struct Registers
     };
   };
 
-  u32 pc;
   u32 hi;
   u32 lo;
-  u32 npc;
+  u32 pc;  // at execution time: the address of the next instruction to execute (already fetched)
+  u32 npc; // at execution time: the address of the next instruction to fetch
 };
 
 enum class Cop0Reg : u8