x86: bpf_jit_comp: Reduce is_ereg() code size
Use the (1 << reg) & mask trick to reduce code size.
x86-64 size difference -O2 without profiling for various
gcc versions:
$ size arch/x86/net/bpf_jit_comp.o*
text data bss dec hex filename
9266 4 0 9270 2436 arch/x86/net/bpf_jit_comp.o.4.4.new
10042 4 0 10046 273e arch/x86/net/bpf_jit_comp.o.4.4.old
9109 4 0 9113 2399 arch/x86/net/bpf_jit_comp.o.4.6.new
9717 4 0 9721 25f9 arch/x86/net/bpf_jit_comp.o.4.6.old
8789 4 0 8793 2259 arch/x86/net/bpf_jit_comp.o.4.7.new
10245 4 0 10249 2809 arch/x86/net/bpf_jit_comp.o.4.7.old
9671 4 0 9675 25cb arch/x86/net/bpf_jit_comp.o.4.9.new
10679 4 0 10683 29bb arch/x86/net/bpf_jit_comp.o.4.9.old
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed