wapd@houxj.UUCP (Bill Dietrich) (07/11/85)
The MMU used by the 3B-2/300 splits the 32-bit virtual address space and its own internal caches into 4 "sections" via the top two bits of the 32-bit address. So to distribute accesses somewhat uniformly through the MMU caches, 3B-2 Unix puts some kernel stuff in section 0 (virtual addresses 0x00000000 - 0x3FFFFFFF), kernel text and data in section 1 (0x40000000 - 0x7FFFFFFF), user text and data in section 2 (0x80000000 - 0xBFFFFFFF), and user stack in section 3 (0xC0000000 - 0xFFFFFFFF). So even for a small program, you will see what looks like "big" addresses. You can see concrete numbers by using the "dump -h" command on "/unix" and your program. This command prints the section header information from an object file. Or use "nm" on those files. Bill Dietrich AT&T Information Systems houxj!wapd