64 bit: what changed
Revision 0 to 1. Removed lines have a minus sign; added lines have a plus sign.
Title: 64 bit
| Old | New | Line | |
|---|---|---|---|
| 1 | + | A **64-bit** processor is one that generally supports a word size of 2<sup>64</sup>, where the constant "[[maxint]]" has the value 2<sup>64</sup>-1, or 18,446,744,073,709,551,615. The signed version of this number can express a range of -18,446,744,073,709,551,615..0 and 0..18,446,744,073,709,551,615. The unsigned version of this number can express a range of 0..18,446,744,073,709,551,616. It also means that programs and data spaces can be much larger than on the older 32-bit and 16-bit machines. | |
| 2 | + | ||
| 3 | + | Examples of 32-bit processors include | |
| 4 | + | ||
| 5 | + | - Newer versions of the X86 microcomputer, Itanium and newer, AMD64 (WINTEL architecture) | |
| 6 | + | ||
| 7 | + | Currently, 64-bit processors (X86) are enhancements of 32-bit processors, and generally can run 32-bit and 16-bit applications. The reverse, however, is not true; 64-bit code cannot run on a machine smaller than 64 bits. | |
| 8 | + | ||
| 9 | + | ## See Also | |
| 10 | + | ||
| 11 | + | - [[Writing portable code regarding the processor architecture]] | |
| 12 | + | - [[Integer]] | |
| 13 | + | - [[32 bit]] | |
| 14 | + | ||
| 15 | + | --- | |
| 16 | + | *From the Free Pascal wiki, page "64 bit", as it stood on 2020-10-10 after a change by Arent, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).* | |
| 17 | + | Category: Processors |