Fieldalign_Shared8 Command - HP DDL D40 Reference Manual

DDL Compiler Commands

FIELDALIGN_SHARED8 Command

The FIELDALIGN_SHARED8 command directs DDL to store data structures in the
dictionary with shared8 alignment. DDL inserts explicit fillers to ensure proper
alignment.
FIELDALIGN_SHARED8
FIELDALIGN_SHARED8 Command Guidelines
The following points are guidelines for using the FIELDALIGN_SHARED8 command:
Use the FIELDALIGN_SHARED8 command to generate TAL (pTAL) or C source
code that will produce optimal performance on a RISC processor.
The FIELDALIGN_SHARED8 command causes DDL to generate explicit
filler fields:
To align an item according to its width
At the end of a structure to make its length a multiple of its alignment
To prevent bit fields less than 16 bits from straddling a 2-byte boundary
FIELDALIGN_SHARED8 Example
The following example shows the C source generated from the given DDL source with
FIELDALIGN_SHARED8 in effect:
DDL Source:
"?FIELDALIGN_SHARED8
def a.
02 b type character 1.
02 c type character 1.
02 d type character 1.
end.
def e type character 1.
def f.
02 g type binary 16.
02 h.
03 i type e.
03 j type a.
02 k type character 1.
02 l type binary 16.
end.
Generated C Source:
/* SCHEMA PRODUCED DATE - TIME :10/13/1995 13:23:16 */
#pragma section a
/* Definition A created on 10/13/1995 at 13:23 */
#pragma fieldalign shared8 __a
Data Definition Language (DDL) Reference Manual—426798-002
FIELDALIGN_SHARED8 Command
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