Questions tagged [intrinsics]

Intrinsics functions are used in compiled languages to use specific CPU instructions outside the scope of the language.

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Header files for x86 SIMD intrinsics

Which header files provide the intrinsics for the different x86 SIMD instruction set extensions (MMX, SSE, AVX, ...)? It seems impossible to find such a list online. Correct me if I'm wrong.
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84votes
4answers
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What are intrinsics?

Can anyone explain what they are and why I would need them? What kind of applications am I building if I need to use intrinsics?
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81votes
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Incrementing 'masked' bitsets

I'm currently in the process of writing a tree enumerator where I've come across the following problem: I'm looking at masked bitsets, i.e. bitsets where the set bits are a subset of a mask, i.e. ...
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36votes
7answers
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How to use VC++ intrinsic functions w/o run-time library

I'm involved in one of those challenges where you try to produce the smallest possible binary, so I'm building my program without the C or C++ run-time libraries (RTL). I don't link to the DLL ...
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28votes
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print a __m128i variable

I'm trying to learn to code using intrinsics and below is a code which does addition compiler used: icc #include<stdio.h> #include<emmintrin.h> int main() { __m128i a = ...
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What are _mm_prefetch() locality hints?

The intrinsics guide says only this much about void _mm_prefetch (char const* p, int i) : Fetch the line of data from memory that contains address p to a location in the cache heirarchy specified ...
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28votes
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Is there a good reference for ARM Neon intrinsics?

The ARM reference manual doesn't go into too much detail into the individual instructions ( http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0348b/BABIIBBG.html ). Is there something ...
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Get member of __m128 by index?

I've got some code, originally given to me by someone working with MSVC, and I'm trying to get it to work on Clang. Here's the function that I'm having trouble with: float vectorGetByIndex( __m128 V, ...
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SSE, intrinsics, and alignment

I've written a 3D vector class using a lot of SSE compiler intrinsics. Everything worked fine until I started to instatiate classes having the 3D vector as a member with new. I experienced odd crashes ...
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Equivalent of InterlockedIncrement in Linux/gcc

It would be a very simple question (could be duplicated), but I was unable to find it. Win32 API provides a very handy set of atomic operations (as intrinsics) such as InterlockedIncrement which ...
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c++ SSE SIMD framework [closed]

Does anyone know an open-source C++ x86 SIMD intrinsics library? Intel supplies exactly what I need in their integrated performance primitives library, but I can't use that because of the copyrights ...
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SIMD and difference between packed and scalar double precision

I am reading Intel's intrinsics guide while implementing SIMD support. I have a few confusions and my questions are as below. __m128 _mm_cmpeq_ps (__m128 a, __m128 b) documentation says it is used to ...
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When will JVM use intrinsics

Why certain code patterns when present within JVM internal classes are turned into an intrinsic function, whereas the same patterns when called from my own class are not. Example: bitCount ...
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Undocumented intrinsic routines

Delphi has this list: Delphi Intrinsic Routines But that list is incomplete. What are the 7 undocumented intrinsic functions, since when and what is their purpose?
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Why and when to use __noop?

I was reading about __noop and the MSDN example is #if DEBUG #define PRINT printf_s #else #define PRINT __noop #endif int main() { PRINT("\nhello\n"); } and I don't see the gain over ...
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