Reference Guide

Chapter 4 81

Assembler Directives and Pseudo-Operations

.ENTER and .LEAVE Pseudo-Operations

The .ENTER and .LEAVE pseudo-operations mark a procedure's entry

and exit points. They instruct the Assembler to generate procedure entry

and exit code sequences based on the information provided in the

.CALLINFO directive.

Syntax

.ENTER

Lines of code

.LEAVE

Discussion

The .ENTER pseudo-operation marks an entry point for the current

procedure. Every procedure that follows the standard procedure-calling

convention must contain one .ENTER pseudo-operation. The calling

conventions are described in the documents under the topic PA-RISC

Architecture at URL: http://www.software.hp.com/STK/. The .LEAVE

pseudo-operation marks a procedure's exit point. Every procedure that

follows the procedure-calling convention must contain one .LEAVE

pseudo-operation. See “.ENTRY and .EXIT Directives” on page 83 for

exceptions.

When the Assembler encounters an .ENTER pseudo-operation, it

generates an entry code sequence according to the parameters in the

.CALLINFO directive for that procedure. Similarly, when the Assembler

encounters a .LEAVE pseudo-operation, it generates an exit code

sequence according to the parameters in the .CALLINFO directive for

that procedure.