Expansion of memset and memcpy calls.

[Kyrill Tkachov]

On 21/10/14 08:37, Ajit Kumar Agarwal wrote:
> Hello All:
>
> Memset and Memcpy calls are extensively used in many benchmarks. Inlining or expansion
> the memcpy and memset calls improves the performance of many performance
> Benchmark.
> I have implemented the expansion of strcmp  to the optimizaed sequence of instruction
> In open64 compiler for AMD x86 target.
>
> Can I suggest and propose to expand the memset and memcpy calls to the sequence
> Of instruction as many targets like ARM are moving implementation of memcpy and
> Memset in assembly instead of C. This makes it easier to expand the memcpy and
> Memset call in gcc.

There is the 'movmem' standard name that backends can expand to 
implement memcpy semantics. For aarch64, for example, look at the 
movmemdi pattern in aarch64.md and the aarch64_expand_movmem helper in 
aarch64.c

Kyrill

>
> To implement this in GCC we need to expand similarly to the implementation as  builtins.
>
> Let me know what do you think.
>
> Thanks & Regards
> Ajit
>
>