Altera Nios II Built-in Functions#

These built-in functions are available for the Altera Nios II family of processors.

The following built-in functions are always available. They all generate the machine instruction that is part of the name.

int __builtin_ldbio (volatile const void *);
int __builtin_ldbuio (volatile const void *);
int __builtin_ldhio (volatile const void *);
int __builtin_ldhuio (volatile const void *);
int __builtin_ldwio (volatile const void *);
void __builtin_stbio (volatile void *, int);
void __builtin_sthio (volatile void *, int);
void __builtin_stwio (volatile void *, int);
void __builtin_sync (void);
int __builtin_rdctl (int);
int __builtin_rdprs (int, int);
void __builtin_wrctl (int, int);
void __builtin_flushd (volatile void *);
void __builtin_flushda (volatile void *);
int __builtin_wrpie (int);
void __builtin_eni (int);
int __builtin_ldex (volatile const void *);
int __builtin_stex (volatile void *, int);
int __builtin_ldsex (volatile const void *);
int __builtin_stsex (volatile void *, int);

The following built-in functions are always available. They all generate a Nios II Custom Instruction. The name of the function represents the types that the function takes and returns. The letter before the n is the return type or void if absent. The n represents the first parameter to all the custom instructions, the custom instruction number. The two letters after the n represent the up to two parameters to the function.

The letters represent the following data types:

<no letter>

void for return type and no parameter for parameter types.

i

int for return type and parameter type

f

float for return type and parameter type

p

void * for return type and parameter type

And the function names are:

void __builtin_custom_n (void);
void __builtin_custom_ni (int);
void __builtin_custom_nf (float);
void __builtin_custom_np (void *);
void __builtin_custom_nii (int, int);
void __builtin_custom_nif (int, float);
void __builtin_custom_nip (int, void *);
void __builtin_custom_nfi (float, int);
void __builtin_custom_nff (float, float);
void __builtin_custom_nfp (float, void *);
void __builtin_custom_npi (void *, int);
void __builtin_custom_npf (void *, float);
void __builtin_custom_npp (void *, void *);
int __builtin_custom_in (void);
int __builtin_custom_ini (int);
int __builtin_custom_inf (float);
int __builtin_custom_inp (void *);
int __builtin_custom_inii (int, int);
int __builtin_custom_inif (int, float);
int __builtin_custom_inip (int, void *);
int __builtin_custom_infi (float, int);
int __builtin_custom_inff (float, float);
int __builtin_custom_infp (float, void *);
int __builtin_custom_inpi (void *, int);
int __builtin_custom_inpf (void *, float);
int __builtin_custom_inpp (void *, void *);
float __builtin_custom_fn (void);
float __builtin_custom_fni (int);
float __builtin_custom_fnf (float);
float __builtin_custom_fnp (void *);
float __builtin_custom_fnii (int, int);
float __builtin_custom_fnif (int, float);
float __builtin_custom_fnip (int, void *);
float __builtin_custom_fnfi (float, int);
float __builtin_custom_fnff (float, float);
float __builtin_custom_fnfp (float, void *);
float __builtin_custom_fnpi (void *, int);
float __builtin_custom_fnpf (void *, float);
float __builtin_custom_fnpp (void *, void *);
void * __builtin_custom_pn (void);
void * __builtin_custom_pni (int);
void * __builtin_custom_pnf (float);
void * __builtin_custom_pnp (void *);
void * __builtin_custom_pnii (int, int);
void * __builtin_custom_pnif (int, float);
void * __builtin_custom_pnip (int, void *);
void * __builtin_custom_pnfi (float, int);
void * __builtin_custom_pnff (float, float);
void * __builtin_custom_pnfp (float, void *);
void * __builtin_custom_pnpi (void *, int);
void * __builtin_custom_pnpf (void *, float);
void * __builtin_custom_pnpp (void *, void *);