Messages in this thread | | | From | Michael Ellerman <> | Subject | Re: [1/4] powerpc/32: add memset16() | Date | Fri, 1 Sep 2017 23:29:54 +1000 (AEST) |
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On Wed, 2017-08-23 at 14:54:32 UTC, Christophe Leroy wrote: > Commit 694fc88ce271f ("powerpc/string: Implement optimized > memset variants") added memset16(), memset32() and memset64() > for the 64 bits PPC. > > On 32 bits, memset64() is not relevant, and as shown below, > the generic version of memset32() gives a good code, so only > memset16() is candidate for an optimised version. > > 000009c0 <memset32>: > 9c0: 2c 05 00 00 cmpwi r5,0 > 9c4: 39 23 ff fc addi r9,r3,-4 > 9c8: 4d 82 00 20 beqlr > 9cc: 7c a9 03 a6 mtctr r5 > 9d0: 94 89 00 04 stwu r4,4(r9) > 9d4: 42 00 ff fc bdnz 9d0 <memset32+0x10> > 9d8: 4e 80 00 20 blr > > The last part of memset() handling the not 4-bytes multiples > operates on bytes, making it unsuitable for handling word without > modification. As it would increase memset() complexity, it is > better to implement memset16() from scratch. In addition it > has the advantage of allowing a more optimised memset16() than what > we would have by using the memset() function. > > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Series applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/da74f659205ea08cb0fd0b3050637b
cheers
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