syscall

---

To refactor `linux-user/mips/cpu_loop.c` to handle your custom syscall more effectively, you can introduce a MIPS-specific base number similar to how ARM handles it with `ARM_NR_BASE`. Here's a suggestion on how you could modify the code:

1. **Define a Base Number:**
   First, define a constant for the MIPS base number in your file.

   ```c
   #define MIPS_SYS_NR_BASE 4000
   ```

2. **Modify Syscall Handling Logic:**

   Update the logic that determines if the syscall is supported by using this base number:

   ```c
   int syscall_num = env->active_tc.gpr[2] - MIPS_SYS_NR_BASE;
   if (syscall_num >= sizeof(mips_syscall_args) / sizeof(struct mips_syscall_args_entry)) {
     ret = -TARGET_ENOSYS;
   } else {
     // Handle the syscall using mips_syscall_args[syscall_num]
   }
   ```

3. **Ensure Proper Array Size Calculation:**

   When checking the size of `mips_syscall_args`, use the correct calculation to determine the number of entries:

   ```c
   sizeof(mips_syscall_args) / sizeof(struct mips_syscall_args_entry)
   ```

By introducing `MIPS_SYS_NR_BASE`, you make the code more maintainable and consistent with ARM's approach, which should help in correctly handling your custom syscall.