From: helpmepro1 at gmail dot com
Operating system: linux
PHP version: 5.2.8
PHP Bug Type: Scripting Engine problem
Bug description: xor,~ bitwise operations are not 32 bit
Description:
------------
the problem is doing bitwise operations with large numbers like larger
then 28 bit.
when i do
negative bitwise operation "~" to 4738698913
in binary
11010011100101100111010100001{29bit}
the number becomes binary
10000000000000000000000000000000{32bit}
expected:
11100101100011010011000101011110
Reproduce code:
---------------
<TEXTAREA STYLE="height:98%;width:98%">
<?php
//
//I think I found out the solution by using GMP function.
//Code:
function gxor($a,$b)
{
$a=gmp_init("$a",10);
$b=gmp_init("$b",10);
return gmp_strval (gmp_xor ($a, $b),10);
}
echo "gxor(-5799680607,167160) = ".gxor(-5799680607,167160)."\n";
echo " as expected -5799843495 \n";
echo " -5799680607^167160 = " .(-5799680607^167160)."\n";
echo " wrong result \n\n";
echo "var_dump(-4738698913) = ";
var_dump(-4738698913);
echo "so this number is float\n\n";
echo "A decbin 43814 SIMPLE = ".decbin(43814)."\n\n";
//a
echo "B decbin -4738698913 NOT WORKING =
".decbin(-4738698913)."\n\n"; //b
echo "C decbin 4738698913 SIMPLE =
".decbin(4738698913)."\n\n";
echo "D decbin abs -4738698913 WORKING =
".decbin(abs(-4738698913))."\n\n";
echo "E decbin ~abs -4738698913 NOT WORKING =
".decbin(~abs(-4738698913))."\n\n";
echo "F decbin ~abs -1738698913 WORKING =
".decbin(~abs(-1738698913))."\n\n";
echo "G decbin ~ -4738698913 64bit expected result:
1111111111111111111111111111111011100101100011010011000101011110\n";
echo "H the 64bit bitwise not is from windows calc.exe\n\n";
echo "from the B and G example i can deduce that php takes the left side
of 64 bit integer instead of the right and returns it as 32 bit (just a
guess)\n\n";
// 1111111111111111111111111111111011100101100011010011000101011110
echo "php version ".PHP_VERSION;
echo "\n";
echo `cat /proc/version`;
echo "\n";
echo `cat /proc/cpuinfo`;
echo "\n";
?>
</TEXTAREA>
Expected result:
----------------
gxor(-5799680607,167160) = -5799843495
as expected -5799843495
-5799680607^167160 = -2147316488
wrong result
var_dump(-4738698913) = float(-4738698913)
so this number is float
A decbin 43814 SIMPLE = 1010101100100110
B decbin -4738698913 NOT WORKING =
10000000000000000000000000000000
C decbin 4738698913 SIMPLE =
11010011100101100111010100001
D decbin abs -4738698913 WORKING =
11010011100101100111010100001
E decbin ~abs -4738698913 NOT WORKING =
1111111111111111111111111111111
F decbin ~abs -1738698913 WORKING =
10011000010111011000111101011110
G decbin ~ -4738698913 64bit expected result:
1111111111111111111111111111111011100101100011010011000101011110
H the 64bit bitwise not is from windows calc.exe
from the B and G example i can deduce that php takes the left side of 64
bit integer instead of the right and returns it as 32 bit (just a guess)
Actual result:
--------------
php version 5.1.6
Linux version 2.6.18-92.1.18.el5PAE (mockbu...@builder16.centos.org) (gcc
version 4.1.2 20071124 (Red Hat 4.1.2-42)) #1 SMP Wed Nov 12 10:02:30 EST
2008
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU E5405 @ 2.00GHz
stepping : 6
cpu MHz : 1995.120
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat
pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc
pni monitor ds_cpl vmx tm2 cx16 xtpr lahf_lm
bogomips : 3992.34
--
Edit bug report at http://bugs.php.net/?id=47246&edit=1
--
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=47246&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=47246&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=47246&r=trysnapshot60
Fixed in CVS:
http://bugs.php.net/fix.php?id=47246&r=fixedcvs
Fixed in CVS and need be documented:
http://bugs.php.net/fix.php?id=47246&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=47246&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=47246&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=47246&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=47246&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=47246&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=47246&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=47246&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=47246&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=47246&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=47246&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=47246&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=47246&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=47246&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=47246&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=47246&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=47246&r=mysqlcfg
