[PATCH v2 net-next] bpf: arm64: remove callee-save registers use for tmp registers

[David Miller]

From: Yang Shi <yang.shi at linaro.org>
Date: Mon, 16 May 2016 16:36:26 -0700

> In the current implementation of ARM64 eBPF JIT, R23 and R24 are used for
> tmp registers, which are callee-saved registers. This leads to variable size
> of JIT prologue and epilogue. The latest blinding constant change prefers to
> constant size of prologue and epilogue. AAPCS reserves R9 ~ R15 for temp
> registers which not need to be saved/restored during function call. So, replace
> R23 and R24 to R10 and R11, and remove tmp_used flag to save 2 instructions for
> some jited BPF program.
> 
> CC: Daniel Borkmann <daniel at iogearbox.net>
> Acked-by: Zi Shen Lim <zlim.lnx at gmail.com>
> Signed-off-by: Yang Shi <yang.shi at linaro.org>

Applied.