The Int64ShllMod32 function performs a left logical shift operation on an unsigned 64-bit integer value. The function provides improved shifting code for left logical shifts where the shift count is in the range 0 - 31.
DWORDLONG Int64ShllMod32(
DWORDLONG Value, |
// specifies unsigned 64-bit integer to shift left logically |
DWORD ShiftCount |
// specifies a shift count in the range 0 - 31 |
); |
The return value is the unsigned 64-bit integer result of the left logical shift operation.
The shift count is the number of bit positions that the value’s bits move.
In a left logical shift operation on an unsigned value, the value’s bits move to the left, and vacated bits on the right side of the value are set to zero.
A compiler can generate optimal code for a left logical shift operation when the shift count is a constant. However, if the shift count is a variable whose range of values is unknown, the compiler must assume the worst case, leading to non-optimal code: code that calls a subroutine, or code that is inline but branches. By restricting the shift count to the range 0 - 31, the Int64ShllMod32 function lets the compiler generate optimal or near-optimal code.
Please note that the Int64ShllMod32 function’s Value parameter and return value are 64-bit values, not LARGE_INTEGER structures.
Int64ShraMod32, Int64ShrlMod32
file: /Techref/os/win/api/win32/func/src/f49_15.htm, 2KB, , updated: 2000/4/7 12:19, local time: 2024/8/23 06:16,
3.136.19.179:LOG IN
|
©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions? <A HREF="http://piclist.com/tecHREF/os/win/api/win32/func/src/f49_15.htm"> Int64ShllMod32</A> |
Did you find what you needed? |
![]() o List host: MIT, Site host massmind.org, Top posters @none found - Page Editors: James Newton, David Cary, and YOU! * Roman Black of Black Robotics donates from sales of Linistep stepper controller kits. * Ashley Roll of Digital Nemesis donates from sales of RCL-1 RS232 to TTL converters. * Monthly Subscribers: Gregg Rew. on-going support is MOST appreciated! * Contributors: Richard Seriani, Sr. |
Ashley Roll has put together a really nice little unit here. Leave off the MAX232 and keep these handy for the few times you need true RS232! |
.