Encouraging preliminary results implementing memcpy in D

[Cym13]

On Wednesday, 13 June 2018 at 16:21:53 UTC, Steven Schveighoffer 
wrote:
> I won't add much, since I'm using a Mac, and those numbers have 
> already been posted.

Reproduction is an important part of the scientific process, 
please post away ;)

Also: memcpyD commit f5fb0fda0dbacc960ced59d7171ff76a95cc2abf on 
Archlinux native x86_64 4.16.13-2 with Intel(R) Core(TM) i7-3520M 
CPU @ 2.90GHz and 7681MB of RAM, with dmd and ldc, no flag and 
optimized.

DMD:

size memcpyC memcpyD
1 50392 30745
2 50189 33515
4 47493 33456
8 50282 33428
16 36385 36061
32 36212 32142
64 50141 31137
128 52947 52785
256 86422 76346
512 131191 128344
1024 227875 291414
2048 444865 449210
4096 826391 823613
8192 1542429 1545051
16384 3264964 3228990
32768 11644816 11902418
65536 23658237 24026304

size memcpyC memcpyD
1 43209 37462
1 42412 38043
1 42079 38002
2 56503 39923
2 50544 38033
4 47760 37239
4 48910 36976
8 51110 38065
8 53761 36297
4 48201 35548
8 54820 38036
16 39360 35409



DMD -O:

core.exception.AssertError at memcpyd.d(9): Assertion failure
----------------
??:? _d_assertp [0xc4e79cc5]
??:? pure nothrow @nogc void 
memcpyd.verify!(real).verify(const(real), const(real)) 
[0xc4e77c2c]
??:? void memcpyd.test!(real).test() [0xc4e76d60]
??:? _Dmain [0xc4e63ecd]

1 42014 26518
2 46086 26486
4 45984 29272
8 48813 26484
16 34866 18126
32 32036 18107
64 46073 20892
128 45964 27993
256 82344 50250
512 133484 94766
1024 216402 270462
2048 436465 443122
4096 815875 801596
8192 1524872 1530453
16384 3721245 3584620
32768 11776185 11739396
65536 23702074 23589480

size memcpyC memcpyD
1 37755 15424
1 40486 15319
1 40505 15352
2 47097 15653
2 46160 15319
4 43180 18110
4 46041 15321
8 46014 15342
8 46066 15341
4 43277 18105
8 45962 15321


LDC:

size memcpyC memcpyD
1 56378 48873
2 59461 49025
4 50481 45299
8 53786 49517
16 46103 39122
32 48100 46139
64 83864 67401
128 83849 90426
256 122471 138309
512 169668 228472
1024 260461 276878
2048 444937 472365
4096 860962 825468
8192 1578929 1567154
16384 3429235 3284611
32768 11941494 11868947
65536 24052536 24112980

size memcpyC memcpyD
1 47853 33403
1 47623 32924
1 48190 33100
2 59752 33146
2 59574 34371
4 53928 35042
4 54131 31991
8 57929 35864
8 57372 32174
4 54901 33253
8 62537 34535
16 52487 38358


LDC -O2:

core.exception.AssertError at memcpyd.d(9): Assertion failure
----------------
??:? _d_assert [0x7fba47d79b35]
??:? void memcpyd.test!(real).test() [0x5638cb483d6e]
??:? _Dmain [0x5638cb47ea30]
size memcpyC memcpyD
1 0 0
2 0 0
4 0 0
8 0 0
16 385 0
32 792 0
64 1542 0
128 2981 0
256 90108 0
512 126316 0
1024 217881 391419
2048 415182 620853
4096 1244805 1240074
8192 2428417 2414095
16384 4863280 4971193
32768 12968909 12966676
65536 26393408 26395410

size memcpyC memcpyD
1 0 0
1 0 0
1 0 0
2 0 0
2 0 0
4 0 0
4 0 0
8 0 0
8 0 0
4 0 0
8 0 0