linux-sg2042/arch/x86/net
Daniel Borkmann 606c88a86c bpf, x86: detect/optimize loading 0 immediates
When sometimes structs or variables need to be initialized/'memset' to 0 in
an eBPF C program, the x86 BPF JIT converts this to use immediates. We can
however save a couple of bytes (f.e. even up to 7 bytes on a single emmission
of BPF_LD | BPF_IMM | BPF_DW) in the image by detecting such case and use xor
on the dst register instead.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-18 16:04:51 -05:00
..
Makefile net: filter: Just In Time compiler for x86-64 2011-04-27 23:05:08 -07:00
bpf_jit.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
bpf_jit_comp.c bpf, x86: detect/optimize loading 0 immediates 2015-12-18 16:04:51 -05:00