Operands on ANDN are swapped.
Tested with the following function:
long test_andn(long v1, long v2){
return (~v1 & v2);
}
Compiled with:
gcc kk.c -mbmi -O3 -Wall
0000000000000910 <test_andn>:
910:c4 e2 c0 f2 c6 andn %rsi,%rdi,%rax
915:c3 retq
916:66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1)
91d:00 00 00
and
gcc kk.c -march=native -O3 -Wall
0000000000000930 <test_andn>:
930: 48 f7 d7 not %rdi
933: 48 89 f8 mov %rdi,%rax
936: 48 21 f0 and %rsi,%rax
939: c3 retq
93a: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1)
The test showed than -mbmi version behaved differently than the
-march native version.
Signed-off-by: Ricardo Ribalda Delgado <address@hidden>