Comments (3)
If your code is switching between AVX and SSE code chronically then yes it could help. You can measure the number of transitions with tools such as sde and estimate what penalty you are getting.
from isa-l.
@gbtucker
thank you for your replay and sde is a really cool tool
After call ISA-L, maybe I would call to libraries that include SSE code, maybe not. So I think for avoiding potential AVX-SSE penalties,should I add VZEROUPPER at the end of any function that uses 256-bit AVX instructions? In the 11.3.1 "Mixing Intel® AVX and Intel SSE in Function Calls" , I found “Assembly/Compiler Coding Rule 71”, it said "Add VZEROUPPER instruction after 256-bit AVX instructions are executed and before any function call that might execute SSE code. Add VZEROUPPER at the end of any function that uses 256-bit AVX instructions."
And the manual also sadi "This instruction has zero latency." in 11.3
So maybe the VZEROUPPER throughput is slow,I found "VZEROUPPER instruction throughput is slow, and is not recommended to preface a transition to AVX code after SEE code execution. The throughput of VZEROALL is also slow. Using either the VZEROUPPER or the VZEROALL instruction is likely to result in performance loss." in 15.2.7.1. But it's for "KNIGHTS LANDING MICROARCHITECTURE AND SOFTWARE OPTIMIZATION", I'm not sure it will happen on the other microarchitectures?
from isa-l.
from isa-l.
Related Issues (20)
- Looking for ARM/PowerPC owner/maintainers HOT 11
- Add isal_zlib_header_init HOT 2
- Error in functional tests for ppc64le HOT 2
- Failed to load symbolec_init_tables HOT 3
- undefined reference to `ec_init_tables' HOT 2
- erasure_code/gf_vect_mul: If the value of len is not aligned with 32B, a non-zero value should be returned
- v2.31.0 tag not annotated HOT 2
- Failed to decompress gz file which has multi-header
- how use raid lib to recover lost data?
- ARM OSX build fails HOT 7
- raid: why does the simd version xor_gen not provide an entry for loop64?
- Windows build fails - yasm doesn't understand %use HOT 4
- If raid xor_gen passed-in array pointers is not aligned to 32B, what's the impact?
- Mention Julia language bindings HOT 7
- Make new release HOT 1
- AVX512 detection failed when cpu supports AVX512 HOT 3
- Does the ISAL library have an API compatible with Rocksdb CRC32C HOT 6
- why crc16_t10dif() may make mistakes but crc16_t10dif_copy() running OK in file storage test ?
- yasm-1.3.0 fails to compiler isa-l: error: unknown preprocessor directive `%use' HOT 1
- segfault in igzip_rand_test stateless test HOT 4
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from isa-l.