Book Image

OpenCL Programming by Example

Book Image

OpenCL Programming by Example

Overview of this book

Research in parallel programming has been a mainstream topic for a decade, and will continue to be so for many decades to come. Many parallel programming standards and frameworks exist, but only take into account one type of hardware architecture. Today computing platforms come with many heterogeneous devices. OpenCL provides royalty free standard to program heterogeneous hardware. This guide offers you a compact coverage of all the major topics of OpenCL programming. It explains optimization techniques and strategies in-depth, using illustrative examples and also provides case studies from diverse fields. Beginners and advanced application developers will find this book very useful. Beginning with the discussion of the OpenCL models, this book explores their architectural view, programming interfaces and primitives. It slowly demystifies the process of identifying the data and task parallelism in diverse algorithms. It presents examples from different domains to show how the problems within different domains can be solved more efficiently using OpenCL. You will learn about parallel sorting, histogram generation, JPEG compression, linear and parabolic regression and k-nearest neighborhood, a clustering algorithm in pattern recognition. Following on from this, optimization strategies are explained with matrix multiplication examples. You will also learn how to do an interoperation of OpenGL and OpenCL. "OpenCL Programming by Example" explains OpenCL in the simplest possible language, which beginners will find it easy to understand. Developers and programmers from different domains who want to achieve acceleration for their applications will find this book very useful.
Table of Contents (18 chapters)
OpenCL Programming by Example
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Built-in data types


OpenCL specification provides its own set of data types, whether vector or scalar. This is important since it will enable the kernel code to be portable across various OpenCL devices and different device compilers. In the following sections we will discuss the different data types, which are defined in the OpenCL specification.

Basic data types and vector types

OpenCL C standard categorizes a list of data types referred to as "basic data types". This is tabulated in the following table. Associated with each basic data type is a vector data type, which can be used by a C programmer. Most of the OpenCL devices do support Instruction Set Architecture (ISA), which take inputs as vector data types. For example, the AMD FMA4 ISA extension supports Fused Multiply Add (FMA) operation on 256 bit vector data. So if these vector data types are used while writing code it is more likely that the vector data type are processed by codes, which uses vector instructions at runtime and is...