Intel® C++ Compiler Classic Developer Guide and Reference

ID 767249
Date 7/13/2023
Public
Document Table of Contents

Intrinsics

This intrinsics section provides an introduction and information on Intel specific intrinsics. The Intel® Intrinsics Guide provides detailed information and a lookup tool for viewing the available Intel intrinsics.

The following is some general information:

  • Intrinsics are assembly-coded functions that let you use C++ function calls and variables in place of assembly instructions.

  • Intrinsics can be used only on the host.

  • Intrinsics are expanded inline eliminating function call overhead. Providing the same benefit as using inline assembly, intrinsics improve code readability, assist instruction scheduling, and help reduce debugging.

  • Intrinsics provide access to instructions that cannot be generated using the standard constructs of the C and C++ languages.

NOTE:

When developing and debugging your program with the Intel® C++ Compiler Classic, compile your sources with ‑D__INTEL_COMPILER_USE_INTRINSIC_PROTOTYPES to take advantage of improved compile-time checking of the intrinsics functions. When done be sure to remove this option as it significantly increases compile time.

Availability of Intrinsics on Intel Processors

Not all Intel® processors support all intrinsics. For information on which intrinsics are supported on Intel® processors, visit the Product Specification, Processors page. The Processor Spec Finder tool links directly to all processor documentation and the datasheets list the features, including intrinsics, supported by each processor.