[PATCH] ARCv2: update memset() so it could be used without double load/stores
Vineet Gupta
Vineet.Gupta1 at synopsys.com
Tue Oct 20 09:03:34 UTC 2015
On Monday 20 July 2015 07:42 PM, Alexey Brodkin wrote:
> From: Claudiu Zissulescu <claziss at synopsys.com>
>
> Existing version of memset() relies on existence of 64-bit load/stores.
> While ARC HS38 may not have those instructions implemented in SoC.
>
> Proposed implementation checks if "-mno-ll64" option was passed to gcc
> (for ARCv2 "-mll64" is set implicitly by default) by checking __LL64__
> definition and if it is not defined uses 32-bit load/stores.
>
> Signed-off-by: Claudiu Zissulescu <claziss at synopsys.com>
> Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
> Cc: Vineet Gupta <vgupta at synopsys.com>
Ping ! Could this patch be applied please !
Thx,
-Vineet
> ---
> libc/string/arc/arcv2/memset.S | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
> diff --git a/libc/string/arc/arcv2/memset.S b/libc/string/arc/arcv2/memset.S
> index d076ad1..0918d37 100644
> --- a/libc/string/arc/arcv2/memset.S
> +++ b/libc/string/arc/arcv2/memset.S
> @@ -52,6 +52,7 @@ ENTRY(memset)
> lpnz @.Lset64bytes
> ;; LOOP START
> PREWRITE(r3, 64) ;Prefetch the next write location
> +#ifdef __LL64__
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> @@ -60,16 +61,45 @@ ENTRY(memset)
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> +#else
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> +#endif
> .Lset64bytes:
>
> lsr.f lp_count, r2, 5 ;Last remaining max 124 bytes
> lpnz .Lset32bytes
> ;; LOOP START
> prefetchw [r3, 32] ;Prefetch the next write location
> +#ifdef __LL64__
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> std.ab r4, [r3, 8]
> +#else
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> + st.ab r4, [r3, 4]
> +#endif
> .Lset32bytes:
>
> and.f lp_count, r2, 0x1F ;Last remaining 31 bytes
>
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