Intel® Parallel Studio XE

Intel® Advisor 2015 Beta Tutorials: Linux* OS

Discover how to find where to add parallelism to a serial application using the Intel® Advisor and the nqueens_Advisor C++ sample application.

This short tutorial demonstrates an end-to-end workflow you can ultimately apply to your own applications:

  1. Survey the target to locate the loops and functions where the target spends the most time.

  • Developers
  • Linux*
  • C/C++
  • Intel® Cluster Studio XE
  • Intel® Parallel Studio XE
  • Intel® Advisor XE
  • Diagnostic 15002: loop was vectorized (Fortran)

     

    Cause:

    For the Intel® Compiler, vectorization is the unrolling of a loop combined with the generation of packed SIMD instructions. Because the packed instructions operate on more than one data element at a time, the loop can execute more efficiently. The above message indicates that the loop was successfully vectorized using packed SIMD instructions. 

    Example:

  • Apple OS X*
  • Linux*
  • Microsoft Windows* (XP, Vista, 7)
  • Microsoft Windows* 8.x
  • Fortran
  • Intel® Composer XE
  • Intel® Fortran Compiler
  • Intel® Fortran Composer XE
  • Intel® Visual Fortran Composer XE
  • Intel® Fortran Studio XE
  • Intel® Parallel Studio XE
  • vectorization
  • Diagnostics
  • Optimization
  • Vectorization
  • The Chronicles of Phi - part 1 The Hyper-Thread Phalanx

    The term phalanx is derived from a military formation used by the ancient Greeks and Romans. The formation generally involved soldiers lining up shoulder to shoulder, shield to shield multiple rows deep. The formation would advance in unison becoming “an irresistible force.” I use the term Hyper-Thread Phalanx to refer to the Hyper-Thread siblings of a core being aligned shoulder-to-shoulder and advancing forward.

    Diagnostic 15134: vectorization support: reference xxxx has unaligned access (Fortran)

    Cause:

    The vectorizer cannot safely use aligned loads or stores for this data access, either because the data are not aligned to an n-byte boundary in memory, or because the compiler does not know the alignment. The compiler must use unaligned memory accesses, which may be less efficient. The value of n depends on the targeted instruction set and corresponds to the width of the vector instructions: 16 for Intel® SSE, 32 for Intel® AVX and 64 for Intel® AVX-512 instructions.

    Example:

  • Apple OS X*
  • Linux*
  • Microsoft Windows* (XP, Vista, 7)
  • Microsoft Windows* 8.x
  • Fortran
  • Intel® Composer XE
  • Intel® Fortran Compiler
  • Intel® Fortran Composer XE
  • Intel® Visual Fortran Composer XE
  • Intel® Fortran Studio XE
  • Intel® Parallel Studio XE
  • error
  • vectorization diagnostic messages
  • alignment
  • Development Tools
  • Vectorization
  • Intel Software Tools Webinar Series Archive

    This free webinar series presented tools, tips, and techniques that will help sharpen your development skills on Intel processors/coprocessors including Intel® Xeon® processor and Intel® Xeon Phi™ coprocessor. Intel technical experts as well as open source innovators discuss topics ranging from compiler techniques including vectorization & OpenMP 4.0, performance libraries, debugging, error checking and tuning to boost application and platform performance. Come to the live sessions with your programming questions for Intel technical experts to answer.

  • Developers
  • C/C++
  • Fortran
  • Intel® Parallel Studio XE
  • Intel® VTune™ Amplifier XE
  • Intel® Inspector XE
  • Intel® Advisor XE
  • Intel® Cilk™ Plus
  • Intel® MPI Library
  • Intel® Threading Building Blocks
  • Intel® Cluster Studio XE
  • Intel® Fortran Studio XE
  • Webinars
  • Intel® Many Integrated Core Architecture
  • Intel® Parallel Studio XE 2013 SP1 for Windows* Update 2

    Intel® Parallel Studio XE 2013 SP1 parallel software development suite combines Intel's C/C++ compiler and Fortran compiler; performance and parallel libraries; error checking, code robustness, and performance profiling tools into a single suite offering.  This new product release includes:

  • Developers
  • Microsoft Windows* (XP, Vista, 7)
  • Microsoft Windows* 8.x
  • C/C++
  • Fortran
  • Intel® Parallel Studio XE
  • Subscribe to Intel® Parallel Studio XE