freebsd kernel with SKQ
c4da2324a3
on all inputs of the form x.75, where x is an even integer and log2(x) = 21. A similar problem occurred when rounding upward. The bug involves the following snippet copied from rint(): i>>=1; if((i0&i)!=0) i0 = (i0&(~i))|((0x100000)>>j0); The constant 0x100000 should be 0x200000. Apparently this case was never tested. It turns out that the bit manipulation is completely superfluous anyway, so remove it. (It tries to simulate 90% of the rounding process that the FPU does anyway.) Also, the special case of +-0 is handled twice (in different ways), so remove the second instance. Throw in some related simplifications from bde: - Work around a bug where gcc fails to clip to float precision by declaring two float variables as volatile. Previously, we tricked gcc into generating correct code by declaring some float constants as doubles. - Remove additional superfluous bit manipulation. - Minor reorganization. - Include <sys/types.h> explicitly. Note that some of the equivalent lines in rint() also appear to be unnecessary, but I'll defer to the numerical analysts who wrote it, since I can't test all 2^64 cases. Discussed with: bde |
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| bin | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| installworld_newk | ||
| installworld_oldk | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| README | ||
| UPDATING | ||
| UPDATING.64BTT | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. Source Roadmap: --------------- bin System/user commands. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberos5 Kerberos5 (Heimdal) package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. sbin System commands. secure Cryptographic libraries and commands. share Shared resources. sys Kernel sources. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html