[PATCH net-next v2 4/4] arm64: bpf: optimize LD_ABS, LD_IND

Zi Shen Lim zlim.lnx at gmail.com
Mon Jun 6 22:22:59 PDT 2016


Remove superfluous stack frame, saving us 3 instructions for every
LD_ABS or LD_IND.

Signed-off-by: Zi Shen Lim <zlim.lnx at gmail.com>
---
 arch/arm64/net/bpf_jit_comp.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index 7ae304e..b2fc97a 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -731,11 +731,8 @@ emit_cond_jmp:
 		emit_a64_mov_i64(r3, size, ctx);
 		emit(A64_SUB_I(1, r4, fp, STACK_SIZE), ctx);
 		emit_a64_mov_i64(r5, (unsigned long)bpf_load_pointer, ctx);
-		emit(A64_PUSH(A64_FP, A64_LR, A64_SP), ctx);
-		emit(A64_MOV(1, A64_FP, A64_SP), ctx);
 		emit(A64_BLR(r5), ctx);
 		emit(A64_MOV(1, r0, A64_R(0)), ctx);
-		emit(A64_POP(A64_FP, A64_LR, A64_SP), ctx);
 
 		jmp_offset = epilogue_offset(ctx);
 		check_imm19(jmp_offset);
-- 
1.9.1




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