alignment

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:

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  • Fortran
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  • 英特尔® Parallel Studio XE Professional Edition
  • error
  • vectorization diagnostic messages
  • alignment
  • 开发工具
  • 矢量化
  • Coding for Performance: Data alignment and structures

    This article collects the general knowledge and Best-Known-Methods (BKMs) for aligning of data within structures in order to achieve optimal performance. 

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  • 订阅 alignment