Altera Nios II Custom - Manual (Page 43)

January 2011 Altera Corporation Nios II Custom Instruction User Guide
B. Custom Instruction Built-in Functions
The Nios II gcc compiler, nios2-elf-gcc , is customized with built-in functions to
support custom instructions. This section lists the built-in functions.
f For more information about gcc built-in functions, refer to www.gnu.org.
Nios II custom instruction built-in functions have the following return types:
■ void
■ int
■ float
■ pointer
Built-in Functions that Return a Void Value
The following built-in functions return a void value:
■ void __builtin_custom_n (int n);
■ void __builtin_custom_ni (int n, int dataa);
■ void __builtin_custom_nf (int n, float dataa);
■ void __builtin_custom_np (int n, void *dataa);
■ void __builtin_custom_nii (int n, int dataa, int datab);
■ void __builtin_custom_nif (int n, int dataa, float datab);
■ void __builtin_custom_nip (int n, int dataa, void *datab);
■ void __builtin_custom_nfi (int n, float dataa, int datab);
■ void __builtin_custom_nff (int n, float dataa, float datab);
■ void __builtin_custom_nfp (int n, float dataa, void *datab);
■ void __builtin_custom_npi (int n, void *dataa, int datab);
■ void __builtin_custom_npf (int n, void *dataa, float datab);
■ void __builtin_custom_npp (int n, void *dataa, void *datab);
Built-in Functions that Return a Value of Type Int
The following built-in functions return a value of type int :
■ int __builtin_custom_in (int n);
■ int __builtin_custom_ini (int n, int dataa);
■ int __builtin_custom_inf (int n, float dataa);
■ int __builtin_custom_inp (int n, void *dataa);