From 252ae40ba91c5da3a792bba7e3dc46b106dec86c Mon Sep 17 00:00:00 2001 From: Tiezhu Yang Date: Mon, 17 Aug 2026 22:07:24 +0800 Subject: [PATCH] LoongArch: BPF: Remove dead move_imm() call in BPF_NEG path The BPF_NEG operation is a unary operator that performs `dst = -dst`. The current code unconditionally executes a move_imm() call before the subtraction, generating useless JITted instructions to load data into the temporary register `t1`. This `t1` register is never used anywhere else in the entire BPF_NEG path. Remove this dead `move_imm()` call to avoid useless instructions. Acked-by: Hengqi Chen Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen --- arch/loongarch/net/bpf_jit.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c index f9ba7b961b04..a5e902eb646c 100644 --- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -869,7 +869,6 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = -dst */ case BPF_ALU | BPF_NEG: case BPF_ALU64 | BPF_NEG: - move_imm(ctx, t1, imm, is32); emit_insn(ctx, subd, dst, LOONGARCH_GPR_ZERO, dst); emit_zext_32(ctx, dst, is32); break;