20110308, 04:38  #1 
Mar 2006
2·3^{5} Posts 
32/64 bit gmpecm issue...
I have recently come across an issue that others on mersenneforum have encountered. When building 64bit gmpecm on Windows, both ecm and p+1 restrict B1 to be < ULONG_MAX, which is always 32bits on Windows. All my comments on code line numbers will be based on the 6.3 release.
The restriction for ecm is on line 904 of ecm.c. This appears to be due to prac() (line 410 of ecm.c) taking an (unsigned long)k. If we could change the definition of prac for 64bit builds to use unsigned long long (or some suitable uint64_t), and change the unsigned long variables used internally in prac to be the same type, then we can fix this issue for Win64 (actually, for all 64bit) builds. For p+1, the restriction is defined on line 975 of pp1.c. There is a comment directly above it stating that: /* since pp1_mul_prac takes an unsigned long, we have to check that B1 <= MAX_ULONG */. This is the same situation as with ecm. pp1_mul_prac is defined on line 147 of lucas.c. If we could change its definition and internal variables to use a suitable uint64_t for 64bit builds, then this issue will also be fixed. This is based on a quick look at the source. There may be (and are, I see lucas_cost will need an update) more functions that need to be adjusted due to this change. Actually, if a 32bit build supports a 64bit data type, can we just allow all builds to select a B1 up to MAX_B1? Or are there other restrictions to keep this from being practical? I know there are probably other (higher?) priorites in developing gmpecm, but is this something the developers can work on? Or, if I could contribute, what would be the recommended way to proceed on an issue such as this? Hopefully we can use this thread to coordinate any effort along these lines. 
20110308, 20:06  #2 
May 2008
Worcester, United Kingdom
1000011011_{2} Posts 
If there are calls to MPIR that involve integers, these will unfortunately only allow 32bit values on Windows x64 at the moment. The MPIR team is now looking at this and it is likely that we will add at least mpz set/get functions for intmax_t and uintmax_t integer types as a way of tackling this problem in places where MPIR is used.
But, as you indicate, this also needs a review of applications such as GMPECM to find where it would make sense to replace integer types with intmax_t or uintmax_t types. Brian 
20110309, 01:54  #3  
Einyen
Dec 2003
Denmark
3202_{10} Posts 
I think the P+1 and ECM maximum value is artificially limited at 2^321, since there is the clear warning messages instead of just a crash like when P1 B2 is chosen too high: http://www.mersenneforum.org/showthread.php?t=14785
Quote:
Quote:
Last fiddled with by ATH on 20110309 at 01:56 

20110309, 02:27  #4  
Einyen
Dec 2003
Denmark
2×1,601 Posts 
Actually it seems I was wrong about P+1, it looks like an actual error. If you do:
ecm pp1 v v v v 5e9 < somenumber.txt you can see it tries a lot of things before the error message: Code:
ecm pp1 v v v v 5e9 < HP49106.txt GMPECM 6.3 [configured with GMP 5.0.1 and enableasmredc] [P+1] Input number is 3472467444205921599314517797503819477589734084122870541677198725 33271934546286669814833105704529883802695727555197511968308548810003942514015685 156434289609169900936632761084050232224864731326076358951406247481 (210 digits) Using MODMULN NTT can handle lmax <= 268435456 choose_P: trying P = 3, eulerphi(P) = 2 choose_P: lmin = 485953849758754 for P = 3 choose_P: lmin > lmax, this P is too small choose_P: trying P = 5, eulerphi(P) = 4 choose_P: lmin = 291572309855253 for P = 5 choose_P: lmin > lmax, this P is too small choose_P: trying P = 9, eulerphi(P) = 6 choose_P: lmin = 161984616586252 for P = 9 choose_P: lmin > lmax, this P is too small choose_P: trying P = 15, eulerphi(P) = 8 choose_P: lmin = 97190769951751 for P = 15 choose_P: lmin > lmax, this P is too small choose_P: trying P = 21, eulerphi(P) = 12 choose_P: lmin = 69421978536965 for P = 21 choose_P: lmin > lmax, this P is too small choose_P: trying P = 17, eulerphi(P) = 16 choose_P: lmin = 85756561722133 for P = 17 choose_P: lmin > lmax, this P is too small choose_P: trying P = 27, eulerphi(P) = 18 choose_P: lmin = 53994872195418 for P = 27 choose_P: lmin > lmax, this P is too small choose_P: trying P = 33, eulerphi(P) = 20 choose_P: lmin = 44177622705342 for P = 33 choose_P: lmin > lmax, this P is too small choose_P: trying P = 45, eulerphi(P) = 24 choose_P: lmin = 32396923317251 for P = 45 choose_P: lmin > lmax, this P is too small choose_P: trying P = 51, eulerphi(P) = 32 choose_P: lmin = 28585520574045 for P = 51 choose_P: lmin > lmax, this P is too small choose_P: trying P = 63, eulerphi(P) = 36 choose_P: lmin = 23140659512322 for P = 63 choose_P: lmin > lmax, this P is too small choose_P: trying P = 75, eulerphi(P) = 40 choose_P: lmin = 19438153990351 for P = 75 choose_P: lmin > lmax, this P is too small choose_P: trying P = 105, eulerphi(P) = 48 choose_P: lmin = 13884395707393 for P = 105 choose_P: lmin > lmax, this P is too small choose_P: trying P = 99, eulerphi(P) = 60 choose_P: lmin = 14725874235114 for P = 99 choose_P: lmin > lmax, this P is too small choose_P: trying P = 135, eulerphi(P) = 72 choose_P: lmin = 10798974439084 for P = 135 choose_P: lmin > lmax, this P is too small choose_P: trying P = 165, eulerphi(P) = 80 choose_P: lmin = 8835524541069 for P = 165 choose_P: lmin > lmax, this P is too small choose_P: trying P = 195, eulerphi(P) = 96 choose_P: lmin = 7476213073212 for P = 195 choose_P: lmin > lmax, this P is too small choose_P: trying P = 189, eulerphi(P) = 108 choose_P: lmin = 7713553170774 for P = 189 choose_P: lmin > lmax, this P is too small choose_P: trying P = 231, eulerphi(P) = 120 choose_P: lmin = 6311088957906 for P = 231 choose_P: lmin > lmax, this P is too small choose_P: trying P = 255, eulerphi(P) = 128 choose_P: lmin = 5717104114809 for P = 255 . . . . . . alot of lines cut out . . . . . . . choose_P: trying P = 780825045, eulerphi(P) = 255467520 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 790524735, eulerphi(P) = 268738560 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 821665845, eulerphi(P) = 278691840 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 851275425, eulerphi(P) = 283852800 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 863017155, eulerphi(P) = 298045440 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 909984075, eulerphi(P) = 304128000 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 936020085, eulerphi(P) = 318504960 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 984518535, eulerphi(P) = 325140480 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 1017041025, eulerphi(P) = 342144000 choose_P: tryphiP > cost = 93952409, this P is too large choose_P: trying P = 1052416365, eulerphi(P) = 348364800 choose_P: tryphiP > cost = 93952409, this P is too large Using B1=5000000000, B2=3231568167643630, polynomial x^1, x0=315177856 P = 88062975, l = 33554432, s_1 = 15206400, k = s_2 = 2, m_1 = 24 Error, maximal step1 bound for P+1 is 4294967295 Please report internal errors at <ecmdiscuss@lists.gforge.inria.fr>. But with ECM the error comes immediately like a hardcoded limit: ecm v v v v 5e9 < hp49106.txt Quote:


20110309, 03:40  #5  
Mar 2006
2×3^{5} Posts 
Quote:
Code:
if (P == 0) { outputf (OUTPUT_ERROR, "Error: cannot choose suitable P value for your " "stage 2 parameters.\nTry a shorter B2min,B2 interval.\n"); return ECM_ERROR; } Alex or Paul (or any ecm dev/admin), what do you think about using intmax_t and uintmax_t for these variables that are currently unsigned long? We can check for existence in some appropriate place (not sure how configure works, maybe there?) and use the defined ones or define our own? 

20110309, 13:46  #6  
Einyen
Dec 2003
Denmark
110010000010_{2} Posts 
I think and hope they are already working on it or planning to: post #14 http://www.mersenneforum.org/showthread.php?t=14785
Quote:


20161215, 17:18  #7 
Oct 2006
Berlin, Germany
2^{2}×157 Posts 
I have now exactly this issue with
GMPECM 6.3 [configured with GMP 5.0.1] [ECM] on Windows 64 bit. It seems to work on Linux 64 bit. I run a C200 with ecm v nn timestamp chkpnt checkpnt maxmem 10000 inp in savea save 7600e6 1 and get Error, maximal step 1 bound for ECM is 4294967295. Please report internal errors at <ecmdiscuss@lists.gforge.inria.fr>. I run the ecm63mpir230core264.exe, for which the download link was provided somewhere here in the forum. Was this fixed in later versions? yoyo 
20161215, 21:48  #8 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
5,939 Posts 
It seems to work on 7.0.4. You should upgrade anyway. There would be speed improvements with later versions of MPIR.

20161215, 21:52  #9 
Oct 2006
Berlin, Germany
274_{16} Posts 
I use now the generix 32/64 bit versions from http://gilchrist.ca/jeff/factoring/index.html.

20161215, 23:35  #10 
Einyen
Dec 2003
Denmark
2·1,601 Posts 
Check this thread: http://mersenneforum.org/showthread.php?t=4087
It should work in the 64bit binaries I posted: Skylake (Windows): gmpecm7svn2988skylake.zip Ivy Bridge (Windows): gmpecm7svn2988ivybridge.zip Haswell (Windows): gmpecm7svn2968haswell.zip Haswell (Linux): gmpecm7svn2975haswell.tar.gz Which processor do you use? I can compile the newest SVN. Last fiddled with by ATH on 20161215 at 23:36 
20161216, 00:04  #11 
Oct 2006
Berlin, Germany
274_{16} Posts 
I distribute the binary to thousands of hosts together with the workunits: http://www.rechenkraft.net/yoyo/apps.php
Therefore I need generic versions, not dedicated to a specific processor architecture, for 32 and 64 bit. For Windows I have ecm 7 already. Now I need it for Linux@x86, Mac, Linux@arm. yoyo 
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