[PATCH v1 2/3] LoongArch: BPF: Remove dead move_imm() call in BPF_NEG path

[Tiezhu Yang]

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.

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
 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 2738b4db1165..5f32b205a6ac 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -894,7 +894,6 @@ 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;
-- 
2.42.0