Alexei Starovoitov wrote: > From: Alexei Starovoitov <ast@xxxxxxxxxx> > > Add a test that currently makes LLVM generate assembly code: > > $ llvm-objdump -S skb_pkt_end.o > 0000000000000000 <main_prog>: > ; if (skb_shorter(skb, ETH_IPV4_TCP_SIZE)) > 0: 61 12 50 00 00 00 00 00 r2 = *(u32 *)(r1 + 80) > 1: 61 14 4c 00 00 00 00 00 r4 = *(u32 *)(r1 + 76) > 2: bf 43 00 00 00 00 00 00 r3 = r4 > 3: 07 03 00 00 36 00 00 00 r3 += 54 > 4: b7 01 00 00 00 00 00 00 r1 = 0 > 5: 2d 23 02 00 00 00 00 00 if r3 > r2 goto +2 <LBB0_2> > 6: 07 04 00 00 0e 00 00 00 r4 += 14 > ; if (skb_shorter(skb, ETH_IPV4_TCP_SIZE)) > 7: bf 41 00 00 00 00 00 00 r1 = r4 > 0000000000000040 <LBB0_2>: > 8: b4 00 00 00 ff ff ff ff w0 = -1 > ; if (!(ip = get_iphdr(skb))) > 9: 2d 23 05 00 00 00 00 00 if r3 > r2 goto +5 <LBB0_6> > ; proto = ip->protocol; > 10: 71 12 09 00 00 00 00 00 r2 = *(u8 *)(r1 + 9) > ; if (proto != IPPROTO_TCP) > 11: 56 02 03 00 06 00 00 00 if w2 != 6 goto +3 <LBB0_6> > ; if (tcp->dest != 0) > 12: 69 12 16 00 00 00 00 00 r2 = *(u16 *)(r1 + 22) > 13: 56 02 01 00 00 00 00 00 if w2 != 0 goto +1 <LBB0_6> > ; return tcp->urg_ptr; > 14: 69 10 26 00 00 00 00 00 r0 = *(u16 *)(r1 + 38) > 0000000000000078 <LBB0_6>: > ; } > 15: 95 00 00 00 00 00 00 00 exit > > Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> > --- Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>