05/17: gnu: xxhash: Detect vector instructions at run time.

[guix-commits]

nckx pushed a commit to branch master
in repository guix.

commit 1d25cfbaf4b707f5af9aafe6ac3d8828c5b89f45
Author: Tobias Geerinckx-Rice <me@tobias.gr>
AuthorDate: Mon Jun 29 15:44:07 2020 +0200

    gnu: xxhash: Detect vector instructions at run time.
    
    * gnu/packages/digest.scm (xxhash)[arguments]: Set DISPATCH=1 make flag
    on x86.
---
 gnu/packages/digest.scm | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/gnu/packages/digest.scm b/gnu/packages/digest.scm
index 7adc12e..78eeb7e 100644
--- a/gnu/packages/digest.scm
+++ b/gnu/packages/digest.scm
@@ -21,7 +21,8 @@
   #:use-module (guix packages)
   #:use-module (guix git-download)
   #:use-module (guix build-system gnu)
-  #:use-module (guix utils))
+  #:use-module (guix utils)
+  #:use-module (ice-9 match))
 
 (define-public xxhash
   (package
@@ -40,6 +41,11 @@
     (arguments
      `(#:make-flags
        (list ,(string-append "CC=" (cc-for-target))
+             ,(match (or (%current-target-system)
+                         (%current-system))
+                ;; Detect vector instruction set at run time.
+                ((or "i686-linux" "x86_64-linux") "DISPATCH=1")
+                (_ "DISPATCH=0"))
              "XXH_FORCE_MEMORY_ACCESS=1" ; improved performance with GCC
              (string-append "prefix=" (assoc-ref %outputs "out")))
        #:phases