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[#21094] [las] lim0/lim1 should not exceed 2^31

Date:
2016-12-30 09:37
Priority:
3
State:
Open
Submitted by:
Paul Zimmermann (zimmerma)
Assigned to:
Nobody (None)
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Summary:
[las] lim0/lim1 should not exceed 2^31

Detailed description
it seems that if lim0/lim1 exceed 2^31, las does not work properly:

pzimmermann@catrel-45:/tmp/tmp.41sbLF1r0R$ /home/pzimmermann/45/cado-nfs/build/catrel-45.loria.fr//sieve/las -allow-largesq -dup -I 16 -lim0 2247483648 -lim1 1100000000 -lpb0 35 -lpb1 35 -fb c59.factorbase.roots.gz -poly rsa768.poly -q1 2816001000 -q0 2816000000 -ncurves0 30 -ncurves1 30 -t 8 -mfb1 105 -mfb0 70
...
# Error, p = 2203219133 does not divide at (N,x) = (5,29320)
Aborted

where the file rsa768.poly is the one from parameters/polynomials/rsa768.poly, and the file c59.factorbase.roots.gz is the corresponding factor base on the algebraic side (lim = 1100000000 and maxbits = 16).
Message  ↓
Date: 2017-10-27 08:34
Sender: Paul Zimmermann

update with master revision 5c8d0af. We still get an error, but a different one
(if we disable the check added in commit 944dc20):

pzimmermann@catrel-30:~/30/cado-nfs$ ./build/catrel-30.loria.fr/sieve/las -poly parameters/polynomials/rsa768.poly -fb /tmp/rsa768.roots.gz -allow-largesq -dup -I 16 -lim0 2247483648 -lim1 1100000000 -lpb0 35 -lpb1 35 -q1 2816001000 -q0 2816000000 -ncurves0 30 -ncurves1 30 -t 8 -mfb1 105 -mfb0 70
...
# Now sieving side-1 q=2816000023; rho=712950190
# Sieving parameters for q~2^32 on side 1
# Sieving parameters: lim0=2247483648 lim1=1100000000 lpb0=35 lpb1=35
# mfb0=70 mfb1=105
# Side 0: log2(maxnorm)=143.82 scale=1.75, logbase=1.485994 bound=141
# Side 1: log2(maxnorm)=252.86 scale=1.00, logbase=2.000000 bound=116
# Sieving side-1 q=2816000023; rho=712950190; a0=-3064550; b0=-79; a1=-17413437; b1=470; J=26912;
# Side 0: log2(maxnorm)=143.82 scale=1.75, logbase=1.485994 bound=141
# Side 1: log2(maxnorm)=252.86 scale=1.00, logbase=2.000000 bound=116
las: /home/pzimmermann/30/cado-nfs/sieve/las-plattice.hpp:126: plattice_info_t::plattice_info_t(fbprime_t, fbroot_t, bool, int): Assertion `a0 <= 0' failed.
Aborted

Date: 2016-12-30 10:07
Sender: Paul Zimmermann

in the meantime, I've made las give an error when lim0 or lim1 >= 2^31
(commit 944dc20)

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