README.md
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19
20# Package cpu
21
22Copied from Go src/internal/cpu
23
24## Extras
25
26### Intel
27
28The `INTEL_DISABLE_EXT` environment variable can control which CPU extensions are available for
29the running process. It should be a comma-separate list of upper-case strings as follows
30
31| Flag | Description |
32| -------- | ----------- |
33| `ALL` | Disable all CPU extensions and fall back to Go implementation |
34| `AVX2` | Disable AVX2 optimizations |
35| `AVX` | Disable AVX optimizations |
36| `SSE` | Disable all SSE optimizations |
37| `SSE4` | Disable SSE42, SSE41 optimizations |
38| `SSSE3` | Disable supplemental SSE3 optimizations |
39| `SSE3` | Disable SSE3 optimizations |
40| `SSE2` | Disable SSE2 optimizations |
41
42Any unrecognized flags will be ignored and therefore it is possible to leave the environment variable with a bogus value such as `NONE` when experimenting.