diff options
Diffstat (limited to 'guix')
| -rw-r--r-- | guix/cpu.scm | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/guix/cpu.scm b/guix/cpu.scm new file mode 100644 index 0000000000..e1911f52a8 --- /dev/null +++ b/guix/cpu.scm @@ -0,0 +1,143 @@ +;;; GNU Guix --- Functional package management for GNU +;;; Copyright © 2021 Ludovic Courtès <ludo@gnu.org> +;;; +;;; This file is part of GNU Guix. +;;; +;;; GNU Guix is free software; you can redistribute it and/or modify it +;;; under the terms of the GNU General Public License as published by +;;; the Free Software Foundation; either version 3 of the License, or (at +;;; your option) any later version. +;;; +;;; GNU Guix is distributed in the hope that it will be useful, but +;;; WITHOUT ANY WARRANTY; without even the implied warranty of +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +;;; GNU General Public License for more details. +;;; +;;; You should have received a copy of the GNU General Public License +;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>. + +(define-module (guix cpu) + #:use-module (guix sets) + #:use-module (guix memoization) + #:use-module (srfi srfi-1) + #:use-module (srfi srfi-9) + #:use-module (ice-9 match) + #:use-module (ice-9 rdelim) + #:export (current-cpu + cpu? + cpu-architecture + cpu-family + cpu-model + cpu-flags + + cpu->gcc-architecture)) + +;;; Commentary: +;;; +;;; This module provides tools to determine the micro-architecture supported +;;; by the CPU and to map it to a name known to GCC's '-march'. +;;; +;;; Code: + +;; CPU description. +(define-record-type <cpu> + (cpu architecture family model flags) + cpu? + (architecture cpu-architecture) ;string, from 'uname' + (family cpu-family) ;integer + (model cpu-model) ;integer + (flags cpu-flags)) ;set of strings + +(define current-cpu + (mlambda () + "Return a <cpu> record representing the host CPU." + (define (prefix? prefix) + (lambda (str) + (string-prefix? prefix str))) + + (call-with-input-file "/proc/cpuinfo" + (lambda (port) + (let loop ((family #f) + (model #f)) + (match (read-line port) + ((? eof-object?) + #f) + ((? (prefix? "cpu family") str) + (match (string-tokenize str) + (("cpu" "family" ":" family) + (loop (string->number family) model)))) + ((? (prefix? "model") str) + (match (string-tokenize str) + (("model" ":" model) + (loop family (string->number model))) + (_ + (loop family model)))) + ((? (prefix? "flags") str) + (match (string-tokenize str) + (("flags" ":" flags ...) + (cpu (utsname:machine (uname)) + family model (list->set flags))))) + (_ + (loop family model)))))))) + +(define (cpu->gcc-architecture cpu) + "Return the architecture name, suitable for GCC's '-march' flag, that +corresponds to CPU, a record as returned by 'current-cpu'." + (match (cpu-architecture cpu) + ("x86_64" + ;; Transcribed from GCC's 'host_detect_local_cpu' in driver-i386.c. + (or (and (= 6 (cpu-family cpu)) ;the "Pentium Pro" family + (letrec-syntax ((model (syntax-rules (=>) + ((_) #f) + ((_ (candidate => integers ...) rest + ...) + (or (and (= (cpu-model cpu) integers) + candidate) + ... + (model rest ...)))))) + (model ("bonnel" => #x1c #x26) + ("silvermont" => #x37 #x4a #x4d #x5a #x5d) + ("core2" => #x0f #x17 #x1d) + ("nehalem" => #x1a #x1e #x1f #x2e) + ("westmere" => #x25 #x2c #x2f) + ("sandybridge" => #x2a #x2d) + ("ivybridge" => #x3a #x3e) + ("haswell" => #x3c #x3f #x45 #x46) + ("broadwell" => #x3d #x47 #x4f #x56) + ("skylake" => #x4e #x5e #x8e #x9e) + ("skylake-avx512" => #x55) ;TODO: cascadelake + ("knl" => #x57) + ("cannonlake" => #x66) + ("knm" => #x85)))) + + ;; Fallback case for non-Intel processors or for Intel processors not + ;; recognized above. + (letrec-syntax ((if-flags (syntax-rules (=>) + ((_) + #f) + ((_ (flags ... => name) rest ...) + (if (every (lambda (flag) + (set-contains? (cpu-flags cpu) + flag)) + '(flags ...)) + name + (if-flags rest ...)))))) + (if-flags ("avx512" => "knl") + ("adx" => "broadwell") + ("avx2" => "haswell") + ;; TODO: tigerlake, cooperlake, etc. + ("avx" => "sandybridge") + ("sse4_2" "gfni" => "tremont") + ("sse4_2" "sgx" => "goldmont-plus") + ("sse4_2" "xsave" => "goldmont") + ("sse4_2" "movbe" => "silvermont") + ("sse4_2" => "nehalem") + ("ssse3" "movbe" => "bonnell") + ("ssse3" => "core2"))) + + ;; TODO: Recognize AMD models (bdver*, znver*, etc.)? + + "x86_64")) + (architecture + ;; TODO: AArch64. + architecture))) |