Introduction to PA-RISC Assembly Language
Summary of Changes for PA-RISC 2.0
Summary of Changes for PA-RISC 2.0
The following features have changed in PA-RISC 2.0 architecture. These changes are explained in more detail in the appropriate locations in this manual.
•A new .DWORD directive reserves 64 bits (a double word) of storage and initializes it to the given value.
•A .LEVEL 2.0 directive should be used as the first directive in the source file to assemble it for a PA-RISC 2.0 system.
•New +DA2.0 option
•New and changed Assembler error messages
Summary of Changes for PA-RISC 2.0W (Wide Mode, 64-bit)
The Assembler for PA-RISC 2.0W, the 64-bit version of PA-RISC 2.0, maintains the same source syntax as that of PA1.x and PA2.0 32-bit mode versions. However, PA2.0W features differ in the features listed below.
•To assemble a source file for a PA-RISC 64-bit system, use a .LEVEL 2.0W directive as the first directive in the source file. See “.LEVEL Directive” on page 93.
•The Assembler generates an Executable and Linking Format (ELF) object file format with PA-RISC 2.0W. Refer to the ELF 64 Object File Format, URL: http://www.software.hp.com/STK/ for details on ELF format.
•PA-RISC 2.0W supports a flat virtual address space of 2**64 bytes, and therefore does not support use of space registers. Use the following syntax when memory operations are used:
ex: LDD disp(b), tgt