This patch implements code-gen for new JMP32 instructions on x86_64.
Cc: Alexei Starovoitov <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Signed-off-by: Jiong Wang <[email protected]>
---
arch/x86/net/bpf_jit_comp.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 5542303..499f1c1 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -882,8 +882,12 @@ xadd: if (is_imm8(insn->off))
case BPF_JMP | BPF_JSGE | BPF_X:
case BPF_JMP | BPF_JSLE | BPF_X:
/* cmp dst_reg, src_reg */
- EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39,
- add_2reg(0xC0, dst_reg, src_reg));
+ if (!imm32) /* JMP32 */
+ EMIT1(add_2mod(0x48, dst_reg, src_reg));
+ else if (is_ereg(dst_reg) || is_ereg(src_reg))
+ EMIT1(add_2mod(0x40, dst_reg, src_reg));
+
+ EMIT2(0x39, add_2reg(0xC0, dst_reg, src_reg));
goto emit_cond_jmp;
case BPF_JMP | BPF_JSET | BPF_X:
@@ -909,7 +913,10 @@ xadd: if (is_imm8(insn->off))
case BPF_JMP | BPF_JSGE | BPF_K:
case BPF_JMP | BPF_JSLE | BPF_K:
/* cmp dst_reg, imm8/32 */
- EMIT1(add_1mod(0x48, dst_reg));
+ if (!src_reg) /* JMP32 */
+ EMIT1(add_1mod(0x48, dst_reg));
+ else if (is_ereg(dst_reg))
+ EMIT1(add_1mod(0x40, dst_reg));
if (is_imm8(imm32))
EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32);
--
2.7.4
