diff options
| author | Tiezhu Yang <yangtiezhu@loongson.cn> | 2025-10-02 22:39:35 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2025-10-02 22:39:35 +0800 |
| commit | 24ff0347bbfda1cee9b4aca29c8eeb1a2b7bd61e (patch) | |
| tree | 0f0bfdb7eaeed4bd151591d08bdbec6e82c55355 | |
| parent | db740f5689e61f2e75b73e5c8e7c985a3b4bc045 (diff) | |
LoongArch: BPF: Optimize sign-extention mov instructions
For 8-bit and 16-bit sign-extention mov instructions, it can use the
native instructions ext.w.b and ext.w.h directly, no need to use the
temporary t1 register, just remove the redundant operations.
Here are the test results:
# modprobe test_bpf test_range=81,84
# dmesg -t | tail -5
test_bpf: #81 ALU_MOVSX | BPF_B jited:1 5 PASS
test_bpf: #82 ALU_MOVSX | BPF_H jited:1 5 PASS
test_bpf: #83 ALU64_MOVSX | BPF_B jited:1 5 PASS
test_bpf: #84 ALU64_MOVSX | BPF_H jited:1 5 PASS
test_bpf: Summary: 4 PASSED, 0 FAILED, [4/4 JIT'ed]
Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
| -rw-r--r-- | arch/loongarch/net/bpf_jit.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c index abfdb6bb5c38..7072db18c6cd 100644 --- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -527,13 +527,11 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext emit_zext_32(ctx, dst, is32); break; case 8: - move_reg(ctx, t1, src); - emit_insn(ctx, extwb, dst, t1); + emit_insn(ctx, extwb, dst, src); emit_zext_32(ctx, dst, is32); break; case 16: - move_reg(ctx, t1, src); - emit_insn(ctx, extwh, dst, t1); + emit_insn(ctx, extwh, dst, src); emit_zext_32(ctx, dst, is32); break; case 32: |