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x86: bpf_jit_comp: add XOR instruction for BPF JIT

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This patch is a follow-up for patch "filter: add XOR instruction for use
with X/K" that implements BPF x86 JIT parts for the BPF XOR operation.

Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Borkmann 2012-09-24 07:34:51 +00:00 committed by David S. Miller
parent 9e49e88958
commit 82c93fcc2e
1 changed files with 9 additions and 0 deletions
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9
arch/x86/net/bpf_jit_comp.c
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@ -335,9 +335,18 @@ void bpf_jit_compile(struct sk_filter *fp)
EMIT1_off32(0x0d, K); /* or imm32,%eax */
break;
case BPF_S_ANC_ALU_XOR_X: /* A ^= X; */
case BPF_S_ALU_XOR_X:
seen |= SEEN_XREG;
EMIT2(0x31, 0xd8); /* xor %ebx,%eax */
break;
case BPF_S_ALU_XOR_K: /* A ^= K; */
if (K == 0)
break;
if (is_imm8(K))
EMIT3(0x83, 0xf0, K); /* xor imm8,%eax */
else
EMIT1_off32(0x35, K); /* xor imm32,%eax */
break;
case BPF_S_ALU_LSH_X: /* A <<= X; */
seen |= SEEN_XREG;
EMIT4(0x89, 0xd9, 0xd3, 0xe0); /* mov %ebx,%ecx; shl %cl,%eax */