02/04: base64: Inline arithmetic operations.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit b2ad9d9b084e52c1657f0df7b22690abb1f86acd
Author: Ludovic Courtès <address@hidden>
Date:   Fri Jan 9 01:01:04 2015 +0100

    base64: Inline arithmetic operations.
    
    * guix/base64.scm (define-alias): New macro.
      (fxbit-field, fxarithmetic-shift, fxarithmetic-shift-left, fxand,
      fxior, fxxor): New aliases.
---
 guix/base64.scm |   22 ++++++++++++++++++++--
 1 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/guix/base64.scm b/guix/base64.scm
index f7f7f5f..e4d2ec5 100644
--- a/guix/base64.scm
+++ b/guix/base64.scm
@@ -4,6 +4,8 @@
 ;; (guix base64) by Nikita Karetnikov <address@hidden> on
 ;; February 12, 2014.
 ;;
+;; Some optimizations made by Ludovic Courtès <address@hidden>, 2015.
+;;
 ;; Copyright © 2009, 2010 Göran Weinholt <address@hidden>
 ;;
 ;; This program is free software: you can redistribute it and/or modify
@@ -33,7 +35,23 @@
           (only (srfi :13 strings)
                 string-index
                 string-prefix? string-suffix?
-                string-concatenate string-trim-both))
+                string-concatenate string-trim-both)
+          (only (guile) ash logior))
+
+
+  (define-syntax define-alias
+    (syntax-rules ()
+      ((_ new old)
+       (define-syntax new (identifier-syntax old)))))
+
+  ;; Force the use of Guile's own primitives to avoid the overhead of its 'fx'
+  ;; procedures.
+  (define-alias fxbit-field bitwise-bit-field)
+  (define-alias fxarithmetic-shift ash)
+  (define-alias fxarithmetic-shift-left ash)
+  (define-alias fxand logand)
+  (define-alias fxior logior)
+  (define-alias fxxor logxor)
 
   (define base64-alphabet
     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/")
@@ -209,4 +227,4 @@
                       line-length #f base64-alphabet port)
        (display (string-append "\n-----END " type "-----\n") port))
       ((port type bv)
-       (put-delimited-base64 port type bv 76)))))
\ No newline at end of file
+       (put-delimited-base64 port type bv 76)))))