commit 55edb45140668ffa9ef8de7f50fd24c2c0f66a96
parent 659a5a81045af899310dca5f70907da287c56d19
Author: Mattias Andrée <maandree@kth.se>
Date: Wed, 27 Apr 2016 15:59:24 +0200
Add STATUS
Signed-off-by: Mattias Andrée <maandree@kth.se>
Diffstat:
| A | STATUS | | | 92 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 92 insertions(+), 0 deletions(-)
diff --git a/STATUS b/STATUS
@@ -0,0 +1,92 @@
+Optimisation progress for libzahl, compared to other big integer
+libraries. These comparisons are for 152-bit integers. Functions
+in parenthesis the right column are functions that needs
+optimisation to improve the peformance of the function in the
+left column. Double-parenthesis means there may be a better way
+to do it.
+
+zset .................... fastest
+zseti ................... tomsfastmath is faster, otherwise fastest
+zsetu ................... tomsfastmath is faster, otherwise fastest
+zneg(a, b) .............. fastest
+zneg(a, a) .............. fastest
+zabs(a, b) .............. fastest
+zabs(a, a) .............. tomsfastmath is faster, otherwise fastest
+zadd_unsigned ........... fastest
+zsub_unsigned ........... fastest
+zadd .................... 98 % of libtommath, otherwise fastest
+zsub .................... 74 % of tomsfastmath, otherwise fastest
+zand .................... 69 % of tomsfastmath, otherwise fastest
+zor ..................... 39 % of tomsfastmath, otherwise fastest
+zxor .................... 52 % of tomsfastmath, otherwise fastest
+znot .................... fastest
+zeven ................... fastest
+zodd .................... fastest
+zeven_nonzero ........... fastest
+zodd_nonzero ............ fastest
+zzero ................... fastest
+zsignum ................. fastest
+zbits ................... gmp is faster, because of bug in libzahl
+zlsb .................... fastest
+zswap ................... fastest
+zlsh .................... fastest
+zrsh .................... fastest
+ztrunc(a, b, c) ......... fastest
+ztrunc(a, a, b) ......... fastest
+zsplit .................. fastest
+zcmpmag ................. gmp is faster, otherwise fastest
+zcmp .................... 80 % of hebimath, gmp is even faster (zcmpmag)
+zcmpi ................... fastest
+zcmpu ................... fastest
+zbset(a, b, 1) .......... fastest
+zbset(a, a, 1) .......... fastest
+zbset(a, b, 0) .......... fastest
+zbset(a, a, 0) .......... fastest
+zbset(a, b, -1) ......... fastest
+zbset(a, a, -1) ......... fastest
+zbtest .................. fastest
+zgcd .................... 26 % of gmp, otherwise fastest (zcmpmag)
+zmul .................... slowest
+zsqr .................... slowest (zmul)
+zmodmul(big mod) ........ slowest ((zmul, zmod))
+zmodsqr(big mod) ........ slowest ((zmul, zmod))
+zmodmul(tiny mod) ....... slowest ((zmul))
+zmodsqr(tiny mod) ....... slowest ((zmul))
+zpow .................... slowest (zmul, zsqr)
+zpowu ................... slowest (zmul, zsqr)
+zmodpow ................. slowest (zmul, zsqr. zmod)
+zmodpowu ................ slowest (zmul, zsqr, zmod)
+zsets ................... 14 % of gmp, otherwise fastest
+zstr_length(a, 10) ...... gmp is faster, otherwise fastest (zdiv, zsqr)
+zstr(a, b, n) ........... 10 % of gmp, otherwise fastest
+zrand(default uniform) .. gmp and tomsfastmath are faster
+zptest .................. slowest (zrand, zmodpow, zsqr, zmod)
+zsave ................... fastest
+zload ................... fastest
+zdiv(big denum) ......... slowest (zdivmod)
+zmod(big denum) ......... slowest (zdivmod)
+zdivmod(big denum) ...... slowest (excluding hebimath)
+zdiv(tiny denum) ........ fastest
+zmod(tiny denum) ........ fastest
+zdivmod(tiny denum) ..... fastest
+
+Note, some corresponding functions are not implemented in
+some other libraries. In such cases, they have been implemented
+in the translation layers (found under bench/). Those
+implementations are often suboptimal, but probably in style
+with what you would write if you need that functionality.
+Note further, that if, for example, you want do perform
+addition and you know that your operands are non-negative,
+you would choose zadd_unsigned in libzahl, but if you are
+using a library that does not have the corrsponding function,
+you are better of with the regular addition (zadd).
+
+Also note, TomsFastMath does not allow arbitrarily large
+integers, which gives is a significant performance advantage.
+Furthermore, not failure check is done with GMP. Additionally,
+hebimath is some functions that are not working correctly;
+those have been excluded from the comparison.
+
+Also note, NOT does not mean the same thing in all libraries,
+for example in GMP it means (-x - 1), thus, znot does not
+use GMP's NOT in the translations layer.
