Developer Guide and Reference

Contents

Using Guided Auto Parallelism in Microsoft Visual Studio*

The Guided Auto Parallelism (GAP) feature helps you locate portions of your serial code that can be parallelized. When you enable analysis using GAP, the compiler guides you to places in your code where you can increase efficiency through automatic parallelization and vectorization.

Running Analysis on a Project

You can start analysis from the Microsoft Visual Studio* IDE in several ways:
  • From the
    Tools
    menu: Select
    Intel Compiler
    Guided Auto Parallelism
    Run Analysis...
    Starting analysis in this way results in a one-time run for the current project. The default values are taken from
    Tools
    Options
    unless you have chosen to override them in the dialog box.
  • From the Diagnostics property page: Use the
    Guided Auto Parallelism Analysis
    property.
    Specifically, choose
    Project
    Properties
    C/C++
    Diagnostics
    and enable analysis using the
    Guided Auto Parallelism Analysis
    property. Enabling analysis in the property page allows you to run an analysis as part of a normal project
    Build
    request in Microsoft Visual Studio*. In this mode, GAP-related settings in
    Tools
    Options
    are ignored, in favor of other GAP-related settings available in the property page.
  • From the context menu: Right-click and select
    Intel Compiler
    Guided Auto Parallelism
    Run Analysis...
    .
    This is equivalent to using the
    Guided Auto Parallelism
    Run Analysis
    option on the
    Tools
    menu.
To receive advice for auto parallelization, be sure that certain property page settings are correct. Select
Project
Properties
C/C++
Optimization [Intel C++]
and set
Parallelization
to
Yes
to enable auto-parallelization optimization. You may also need to set the
Optimization
level at option
O2
or higher.
To do this, use the
Optimization
property page.

GAP Scenarios

To illustrate how the various GAP settings work together, consider the following scenarios:
Scenario
Result
The GAP analysis setting in the property pages is set to Enabled.
Analysis always occurs for the project, whenever a regular project build occurs. Other analysis settings specified in the property pages are used. Analysis setting in
Tools
Options
are ignored.
The Gap analysis setting in the property pages is set to Disabled, and GAP is run from the
Tools
menu.
Analysis occurs for this one run. The default values for this analysis are taken from
Tools
Options
and can be overridden in the dialog box. Options specified in the property pages are also used, but will be overridden by any specified analysis option.
The GAP analysis setting in the property pages is set to Disabled, and GAP options are set in
Tools
Options
.
No analysis occurs, unless analysis is explicitly run from the
Tools
menu.

Running Analysis on a File or within a File

Right-click on
Guided Auto Parallelism
context menu item to run analysis on the following:
  • Single file:
    Select a file and
    right-click
    .
  • Function (routine):
    Right-click
    within the function scope.
  • Range of lines:
    Select one or more lines for analysis and
    right-click
    .

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804