Using the GNU Compiler Collection (GCC): BPF Built-in Functions

6.60.12 BPF Built-in Functions

The following built-in functions are available for eBPF targets.

Built-in Function: unsigned long long __builtin_bpf_load_byte (unsigned long long offset): Load a byte from the struct sk_buff packet data pointed by the register %r6 and return it.

Built-in Function: unsigned long long __builtin_bpf_load_half (unsigned long long offset): Load 16-bits from the struct sk_buff packet data pointed by the register %r6 and return it.

Built-in Function: unsigned long long __builtin_bpf_load_word (unsigned long long offset): Load 32-bits from the struct sk_buff packet data pointed by the register %r6 and return it.