PLX structure reflects both Amode 31 & 64 C-header files .
Original Publication Date: 2000-Apr-01
Included in the Prior Art Database: 2003-Jun-18
PLX structure reflects both Amode 31 64 C-header files . C-headers can be transformed from Amode 31 to Amode 64 simply by increasing the length of the pointers. This approach is the most convent for C programmers; however, this changes the offsets and alignments of many fields. UU Unix system services must process both Amode structures. Existing methods of solving this problem include: copying Amode 31 and Amode 64 structures to a common area, re-baseing each section where offsets change, use a UNION for all fields after first offset change and have different names for the same fields and/or place all 64-bit pointers at the end of the structure leaving reserved space at their former location. This invention allows these relocated fields to be accesses in either mode's structure, based on the caller's PSW-Amode-64-bit, with just a recompile. The PLX structure accommodates both Amode 31 and Amode 64 callers with a minimum of Amode unique code. In the example, field "SpbAmode64" maps to bit 31 of a copy of the callers PSW and has the value 1 when the caller is in Amode 64.