Assembly Language Coding Guidelines

Assembly Language Coding Guidelines

This section describes techniques for writing assembler code which can be compiled and run as either a 32-bit or 64-bit executable. These techniques are based on using certain predefined variables of the compiler, and on macros defined in sys/asm.h and sys/regdef.h which rely on those compiler predefines. Together, they enable a fairly easy conversion of existing assembly code to run in either the 32-bit or LP64 compilation model. They also allow retargeted assembler code to look fairly uniform in the way it is converted.

Overview and Predefined Variables
LP64 Model Implications for Assembly Language Code