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Update documentation to reflect per OS support.

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Fixes #16
This commit is contained in:
Guillaume Chatelet 2018-02-13 10:57:49 +01:00
parent 7634420f31
commit bc8df0c1c5
1 changed files with 11 additions and 11 deletions
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README.md
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@ -124,23 +124,23 @@ flags : aes, avx, sse4_1, sse4_2, ssse3
<a name="support"></a>
## What's supported
| | x86 | ARM | AArch64 | MIPS | POWER |
|---------------------------- | :-: | :-: | :-----: | :----: | :-----: |
|Features revealed from CPU | yes | no* | no* | not yet | not yet |
|Features revealed from Linux | no | yes | yes | yes | not yet |
|Microarchitecture detection | yes | no | no | no | not yet |
|Windows support | yes | no | no | no | not yet |
| | x86³ | ARM | AArch64 | MIPSel | POWER |
|---------|:-------:|:-------:|:-------:|:-------:|:-------:|
| Android | yes² | yes¹ | yes¹ | yes¹ | not yet |
| iOS | not yet | not yet | not yet | not yet | not yet |
| Linux | yes² | yes¹ | yes¹ | yes¹ | not yet |
| MacOs | yes² | yes¹ | yes¹ | yes¹ | not yet |
| Windows | yes² | not yet | not yet | no | no |
- **Features revealed from CPU.** features are retrieved by using the `cpuid`
instruction. *Unfortunately this instruction is privileged for some
architectures, in which case we fall back to Linux.
- **Features revealed from Linux.** We gather data from several sources
1. **Features revealed from Linux.** We gather data from several sources
depending on availability:
+ from glibc's
[getauxval](https://www.gnu.org/software/libc/manual/html_node/Auxiliary-Vector.html)
+ by parsing `/proc/self/auxv`
+ by parsing `/proc/cpuinfo`
- **Microarchitecture detection.** On x86 some features are not always
2. **Features revealed from CPU.** features are retrieved by using the `cpuid`
instruction.
3. **Microarchitecture detection.** On x86 some features are not always
implemented efficiently in hardware (e.g. AVX on Sandybridge). Exposing the
microarchitecture allows the client to reject particular microarchitectures.