.ENTER and .LEAVE Pseudo-Operations

Syntax

Lines of code

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 ” 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.

Example

This example shows the placement of the .ENTER and .LEAVE pseudo-operations.

   .SPACE $TEXT$
   .SUBSPA $CODE$
entrypt
   .PROC
   .CALLINFO
   .ENTER
   SH1ADD       %arg0,%arg1,%ret0
   .LEAVE
   .PROCEND
   .EXPORT entrypt,ENTRY
   .END