Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
| Path | csiph.com!newsfeed.hal-mli.net!feeder3.hal-mli.net!newsfeed.hal-mli.net!feeder1.hal-mli.net!npeer03.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!border3.nntp.dca.giganews.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail |
|---|---|
| NNTP-Posting-Date | Fri, 09 Mar 2012 16:53:55 -0600 |
| Message-ID | <4F5A8A03.3657@mindspring.com> (permalink) |
| Date | Fri, 09 Mar 2012 17:53:55 -0500 |
| From | pete <pfiland@mindspring.com> |
| Reply-To | pfiland@mindspring.com |
| Organization | PF |
| X-Mailer | Mozilla 3.04Gold (WinNT; I) |
| MIME-Version | 1.0 |
| Newsgroups | comp.lang.c |
| Subject | Re: difference between ~0U and ~0 |
| References | <6ee3baa7-5370-4fb6-acfe-262f2bc6036e@sc10g2000pbc.googlegroups.com> <4F58BA48.527D@mindspring.com> <24006453.364.1331218377093.JavaMail.geo-discussion-forums@vbcu2> |
| Content-Type | text/plain; charset=us-ascii |
| Content-Transfer-Encoding | 7bit |
| Lines | 34 |
| X-Usenet-Provider | http://www.giganews.com |
| NNTP-Posting-Host | 4.154.221.196 |
| X-Trace | sv3-z5oxS729/SDUtdd3/A+IMN55rOMqxIHA3VpgzeZd6DRVhNnkw96lLy15B1EKN8YVRhC74vQpTTu8XVy!uBgV5hj8+fM6MhkoJ96q9Mb6XOTgjBEnxra1hIK0xwFYc/NB+NLldZ+ftmCUfahNb/fMQ21Aotkb!lnOJcbM7PZE= |
| X-Abuse-and-DMCA-Info | Please be sure to forward a copy of ALL headers |
| X-Abuse-and-DMCA-Info | Otherwise we will be unable to process your complaint properly |
| X-Postfilter | 1.3.40 |
| X-Original-Bytes | 1984 |
| X-Received-Bytes | 2125 |
| Xref | csiph.com comp.lang.c:18415 |
Show key headers only | View raw
James Piper wrote: > > On Thursday, March 8, 2012 8:55:20 AM UTC-5, pete wrote: > > somenath wrote: > > > > > According to my understanding ~0 is -1. > > > So I will get all bit 1 as a > > > result of ~0 in 2's complement system. > > > > Close, but backwards. > > > > ~0 is all bit 1. > > > > So you will get -1 as a > > result of ~0 in 2's complement system. > That's true. > > 1 in 8-bit format is: 0000 0001 > To get neg- 1: > 1. Negate bits. 1111 1110 > 2. Add 1: 1111 11111 > > Same results regardless of the bit size. Another way for negatising in two's complement is: 1. subtract 1. 0000 0000 2. Negate bits: 1111 11111 I've worked on assembly code that had it done either way in different parts of the code. I don't know if it was done by the same person. -- pete
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
difference between ~0U and ~0 somenath <pal_somenath@emc.com> - 2012-03-03 20:03 -0800
Re: difference between ~0U and ~0 Stephen Sprunk <stephen@sprunk.org> - 2012-03-03 22:55 -0600
Re: difference between ~0U and ~0 BGB <cr88192@hotmail.com> - 2012-03-03 23:01 -0700
Re: difference between ~0U and ~0 Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-03-04 12:50 +0000
Re: difference between ~0U and ~0 pete <pfiland@mindspring.com> - 2012-03-08 08:55 -0500
Re: difference between ~0U and ~0 James Piper <usenet@jamespiper.com> - 2012-03-08 06:52 -0800
Re: difference between ~0U and ~0 pete <pfiland@mindspring.com> - 2012-03-09 17:53 -0500
Re: difference between ~0U and ~0 Tim Rentsch <txr@alumni.caltech.edu> - 2012-03-09 15:11 -0800
Re: difference between ~0U and ~0 pete <pfiland@mindspring.com> - 2012-03-09 18:52 -0500
csiph-web