High Level Assembler: Macro Programming.

This course covers the macro facilities available with the High Level Assembler. It also discusses advanced macro programming techniques, such as abstract data types, inheritance and function overlaying.

The course is intended for:

• Experienced Assembler programmers needing to brush up on their macro programming skills.
• Assembler programmers with some experience needing to expand their understanding of macro facilities available.

This overview comes in three parts, which are presented in sequence below:

1. Course Description
2. Course Objectives
3. Topical Outline

Course Description

Recommended Duration: 2 Days

Benefits: Students who complete this course will be able to write or maintain macros for Assembler programs. The emphasis is on learning the relevant macro facilities available as well as learning to use them to implement an advanced programming environment.

Audience: Experienced Assembler programmers needing to acquire additional macro programming skills.

Prerequisites: At the very least the student entering this course should have background in using ISPF/PDF or a similar product used for creating programs and submitting jobs. Some experience in writing programs in Assembler.

Related IBM Materials. With IBM's permission this course is based upon John Ehrman's SHARE presentation "Assembler as a Higher Level Language: Macros and Conditional Assembly Techniques".
Access to the following IBM manual in the classroom is recommended (via hardcopy, BookManager, etc.):

• SC26-4940 - High Level Assembler reference

Major Topics Include:

• Conditional Assembly Language
• Statement Selection
• Statement Generation and Substitution
• External Conditional Assembly Functions
• Debugging Conditional Assembly Language
• Macro Facility concepts
• Macro Definition
• Macro Comments and Readability
• Macro Parameters
• Macro Arguments Attributes
• Global Variables
• Macro Debugging Techniques
• Defining Symbols
• Generating a Sequence of Values
• MVC with Source Operand's Length
• Converting between Hex and Decimal
• Named Integer Constants
• AREAD and AINSERT
• Macro Recursion
• Bit handling
• Advanced Bit Handling
• Defining and Using Data Types
• Type Checking
• Encapsulated Abstract Data Types
• Front-ending Macros and Instructions

Note 1:
This course is based on the most current version (V1R6) of the High Level Assembler.

Note 2:
The course treats object oriented concepts, but is not intended as in introduction to OO-concepts.

Note 3:
All course material is in American English. Oral explanation will be in English by default, but is also available in Dutch, German, and/or French.

Course Objectives

On successful completion of this course, the student, with the aid of the appropriate reference materials, should be able to:

1. Enhance assembler programs with conditional assembly techniques to support program variations from a single source.
   
   
2. Define and create assembler macros using the following techniques:
   
   
   1. Source and/or macro library definitions
      
      
   2. Nested macro definitions
      
      
   3. Nested and/or recursive macro calls
      
      
   4. Keyword parameters and/or positional parameters
      
      
   5. Processing of sublists of parameters
      
      
   6. Inheritance and function overlaying (polymorphism)
      
      
   7. Abstract data types, encapsulation and type checking
      
      
   8. Front-ending or replacing existing macros and/or instructions
   
   
3. Document the programs and macros with comments to assist in maintenance and understanding of the code
   
   
4. Debug the resulting code of errors

Topical Outline

Day One

Conditional Assembly and Macro Overview

The Conditional Assembly Language

• Evaluation, Substitution, and Selection

Variable Symbols

• Declaring Variable Symbols
• Substitution
• Comments on Substitution, Evaluation, and Re-scanning

Assigning Values to Variable Symbols

• Evaluating Conditional-Assembly Expressions
• Evaluating and Assigning Arithmetic Expressions
  • Internal Arithmetic Functions
  • SETA statements vs EQU Statements
• Evaluating and Assigning Boolean Expressions
• Evaluating and Assigning Character Expressions
  • String Concatenation
  • Substrings
  • String Lengths
  • Internal Character Functions
• External Conditional-Assembly Functions
• Conditional Expressions with Mixed Operand Types

Displaying Variable Symbol Values

Statement Selection

• Sequence Symbols
• The ANOP Statement
• The AGO Statement
• The Extended AGO Statement
• The AIF Statement
• The Extended AIF Statement
• Logical Operators in SETx and AIF Statements

Examples of Conditional Assembly

• Example 1: Generate a Sequence of Byte Values
• Example 2: Generating System-Dependent I/O Statements

Conditional Assembly Language Eccentricities

Basic Macro Facility Concepts

• What is a Macro Facility
• Benefits of Macro Facilities

The Macro Concept: Fundamental Mechanisms

• Text Insertion
• Text Parameterization and Argument Association
• Text Selection
• Macro Call Nesting
• Macro Definition Nesting

The Assembler Language Macro Definition

• Macro Instruction Definition Example
• Macro Instruction Recognition Rules
• Macro Instruction REcognition Details
• Macro Definition Encoding
• Nested Macro Definition in High Level Assembler
• Macro Expansion, Generated Statements, MEXIT

Macro Comments and Readability Aids

• Example 1: Define Equated Symbols for Registers

Macro Parameters and Arguments

• Macro Definition Parameters
• Macro Instruction Arguments
• Macro Parameter-Argument Association
• Example 2: Generate a Sequence of Byte Values
• Macro Parameter Usage in Model Statements

Macro Argument Attributes and Structures

• Macro Instruction Argument Properties: Type Attribute
• Macro Instruction Argument Properties: Count Attribute
• Macro Instruction Argument Properties: Number Attribute
• Macro Instruction Argument Lists and Sublists
• Macro Instruction Argument Lists and &SYSLIST Variable Symbol

Global Variable Symbols

• Variable Symbol Scope Rules: Summary

Macro Debugging Techniques

• Macro Debugging: The MNOTE statement
• Macro Debugging: The MHELP statement
• Macro Debugging: The ACTR statement
• Macro Debugging: The LIBMAC option
• Macro Debugging: The PRINT MCALL statement

IBM Macro Libraries

Day Two

Macro Techniques

• Macro Techniques Case Studies

Case Study 1: Defining Equated Symbols for Registers

Case Study 2: Generating a Sequence of Byte Values

Case Study 3: 'MVC2' Macro Uses Source Operand Length

Case Study 4: Conversion Between Hex and Decimal

• Macro-time Conversion from Hex to Decimal
• Macro-time Conversion from Decimal to Hex

Case Study 5: Generate a List of Named Integer Constants

Case Study 6: Using the AREAD Statement

• Case Study 6a: Creating Length-Prefixed Message Texts
  • Simple Prefixed Message Text
  • More General Prefixed Message Text
  • Prefixed Message Text with the AREAD Statement
• Case Study 6b: Block Comments

Case Study 7: Macro Recursion

• Recursion Example 1: Indirect Addressing
• Recursion Example 2: Factorial Function Values
• Recursion Example 3: Fibonacci Numbers

Case Study 8: Defining Macros for Bit-Handling Operations

• Basic Bit-Handling Techniques
• Case Study 8a: Bit-Handling Macros - Simple Forms
  • Simple Bit-Manipulation Macros
  • Simple Bit-Manipulation Macros: Setting Bits ON
  • Simple Bit-Manipulation Macros: Setting Bits OFF
  • Simple Bit-Testing Macros
• Case Study 8b: Bit-Handling Macros - Advanced Forms
  • Bit-Handling 'Micro Language' and 'Micro Compiler'
  • Declaring Bit Names
  • Improved Bit-Manipulation Macros
  • Using Declared Bit Names in a BITON Macro
  • Using Declared Bit Names in a BBITON Macro

Case Study 9: Defining and Using Data Types

• Case Study 9a: Type Sensitivity - Simple Polymorphism
• Shortcomings of Assembler-Assigned Types
• Symbol Attributes and Lookahead Mode
  • The LOCTR Statement
• Case Study 9b: Type Checking
  • Instruction-Operand Type Checking
  • Instruction-Operand Type Checking (Generalized)
• The AINSERT Statement
• User-Defined Assembler Type Attributes
  • Instruction-Operand-Register Type Checking
• Case Study 9c: Encapsulated Abstract Data Types
  • Calculating with Date Variables
  • Calculating with Interval Variables
• Comparison Operators for Dates and Intervals

Case Study 10: Front-Ending a Macro

• Summary

External Conditional Assembly Functions

• SETAF External Function Interface
  • Arithmetic-Valued Function Example: LOG2
• SETCF External Function Interface
  • String-Valued Function Example: REVERSE
• Installing the LOG2 and REVERSE Functions

Remarks? Questions? More information? Select the topic of your choice or e-mail us with your questions.

To the Course Description
To the Course Objectives
To the Topical Outline

This site is a member of WebRing. You are invited to browse the list of mainframe-loving sites.		Dinos are not dead. They are alive and well and living in data centers all around you. They speak in tongues and work strange magics with computers. Beware the dino! And just in case you're waiting for the final demise of these dino's: remember that dinos ruled the world for 155-million years!
Dinos and other anachronisms [ Join Now | Ring Hub | Random | << Prev | Next >> ]

© Copyright B.V. Bixoft 1997-2010. All rights reserved.
Bixoft ® is a trademark of B.V. Bixoft
e-mail Bixoft.