compiler design

1. BASIC CONCEPTS OF
PARALLELIZATION
(CD)
by,
K.B.Snega,M.sc(CS).,
NADAR SARASWATHI COLLEGE
OF ARTS AND SCIENCE,THENI

2. Parallel programming
model
 A programming model is a collection of
program abstraction providing a programmer
a simplified and transparent view of computer
H/W and S/W.
 A parallel programming is an abstraction of
parallel computer architecture with which it is
convenient to express algorithms and their
composition in programs.

3. Five model are designed that exploits
parallelism :
• Shared-variable model.
 Message-passing model.
 Data parallel model.
 Object oriented model.
 Functional and logic model.

4. SHARED VARIABLE
MODEL
 Variables may be shared
or restricted.
 These model can
automatically generate the
appropriate
communication statements
based on shared variable
for SPMD(Simple Program
Multiple data).

5. MESSAGE PASSING MODEL
 Synchronous Message Passing –
It is must synchronize the sender process and the
receiver process in time and space.
 Asynchronous Message Passing –
It does not require message sending and
receiving be synchronized in time and space.
Non blocking can be achieved.
 Distributing the computations-
Subprogram level is handled rather than at the
instructional or fine grain process level in a tightly
coupled multiprocessor.

6. DATA PARALLEL MODEL
 It is easier to write and to debug because
parallelism is explicitly handled by hardware
synchronization and flow control.
 It requires the use of pre-distributed data
sets.
 Synchronization is done at compile time
rather than run time.
 The following are some issued handled
1. Data Parallelism
2. Array Language Extensions
3. Compiler support

7. OBJECT ORIENTED MODEL
 Object are created and manipulated dynamically.
 Processing is performed using object.
 Concurrent programming model are built up from
low level object such as processes, queue and
semaphore.
 C- oop achieve parallelism using three methods,
1.pipeline concurrency
2.Divide and conquer concurrency
3.Co-operating problem solving

8. FUNCTIONAL AND LOGICAL
MODEL
 Two language-oriented programming for
parallel processing are purposed.
 Functional programming model such as
LISP, SISAL, Strand 88.
 Logic programming model as prolog.
 Based on predicate logic, logic
programming is suitable for solving large
database queries.

9. PARALLEL CONTROL LANGUAGE
 Special language construct and data array
expression for exploiting parallelism in
program.
 First is FORTRAN 90 array notation.
 Parallel flow control is achieve using do across
and do all type of keyword which is use in the
FORTRAN 90.
 Same we also use FORK and JOIN method.

10. OPTIMIZING COMPILER
 The role of compiler to remove the burden
of program optimization and code
generation.
 A parallelizing compiler consist of the
three major phases.
 Flow analysis.
 Optimization.
 Code generation.

11. “Compilation phases in parallel code generation”

12. ISSUES IN PARALLELIZATION
 Amount of parallelizable CPU bound work.
 Task Granularity.
 Load Balancing.
 Memory allocation and Garbage collection.
 Locality issues.