[PATCH] ARCv2: update memset() so it could be used without double load/stores

[Vineet Gupta]

On Tuesday 20 October 2015 02:33 PM, Vineet Gupta wrote:
> 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 !

Ping !

> 
> 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
>>