• Like
ELENA MICROPROCESSOR
Upcoming SlideShare
Loading in...5
×

ELENA MICROPROCESSOR

  • 285 views
Uploaded on

MKU

MKU

More in: Education
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
285
On Slideshare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
5
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. MADURAI KAMARAJ UNIVERSITY SYSTEM SOFTWERE THE ELENA MACRO PROCESSOR By:-Ranjeet Kumar MCA 2nd year Reg.no:-B244039
  • 2. macro processor  A general-purpose macro processor or general purpose preprocessor is a macro processor that is not tied to or integrated with a particular language or piece of software.  A macro processor is a program that copies a stream of text from one place to another, making a systematic set of replacements as it does so.  Macro processors are often embedded in other programs, such as assemblers and compilers. Sometimes they are standalone programs that can be used to process any kind of text.
  • 3. THE ELENA MACRO PROCESSOR  ELENA was developed as a researched tool, not as a commercial software product.  However the same design and implementation techniques could be used in developing other general- purpose macro processors.  Further information about ELENA can be found in Barcucci and Pelacani(1984).
  • 4. The ELENA Macro Processor  Macro definitions in ELENA are composed of a header and a body  The header consists of keywords and parameter markers, which are identified by the character %  At least one of the first two token s in a macro header must be a keyword, not a parameter marker  The macro processor appends a numeric value to create unique labels  ELENA provides macro-time variables and macro-time instructions that can be used to control the macro expansion  The IF statement is a macro-time conditional “go to” statement  The macro is identified by the sequence of keywords that appear in its header
  • 5. For example, a macro with the header %1 = %2 + %3 Could be invoked as ALPHA = BETA + GAMMA and a macro with header ADD %1 TO THE VALUE OF %2 could be invoked as ADD 10 TO THE VALUE OF INDEX
  • 6. Cont…. %1:=ABSDIFF(%2,%3) (a) %1=(%2)>(%3) ? (%2) – (%3) : (%3) – (%2) (b)
  • 7. Cont……
  • 8. Thanks…..