[bug#70398] [PATCH 2/5] packages: Reduce bloat induced by ‘sanitize-inputs’.

[Ludovic Courtès]

At -O1, peval does the bulk of the optimization work and it cannot
reduce things like (null? (list 1 2)), unlike what happens in CPS at
-O2.  Thus, reduce the part of ‘sanitize-inputs’ that’s inlined.

* guix/packages.scm (maybe-add-input-labels): New procedure.
(sanitize-inputs): Turn into a macro; use ‘maybe-add-input-labels’.

Change-Id: Id2283bb5a2f5d714722200bdcfe0b0bfa606923f
---
 guix/packages.scm | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/guix/packages.scm b/guix/packages.scm
index 930b1a3b0e..bd6724cdd4 100644
--- a/guix/packages.scm
+++ b/guix/packages.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2012-2023 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2012-2024 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2014, 2015, 2017, 2018, 2019 Mark H Weaver <mhw@netris.org>
 ;;; Copyright © 2015 Eric Bavier <bavier@member.fsf.org>
 ;;; Copyright © 2016 Alex Kost <alezost@gmail.com>
@@ -430,15 +430,26 @@ (define %cuirass-supported-systems
   ;; <https://lists.gnu.org/archive/html/guix-devel/2017-03/msg00790.html>.
   (fold delete %supported-systems '("mips64el-linux" "powerpc-linux" 
"riscv64-linux")))
 
-(define-inlinable (sanitize-inputs inputs)
-  "Sanitize INPUTS by turning it into a list of name/package tuples if it's
-not already the case."
-  (cond ((null? inputs) inputs)
+(define (maybe-add-input-labels inputs)
+  "Add labels to INPUTS unless it already has them."
+  (cond ((null? inputs)
+         inputs)
         ((and (pair? (car inputs))
               (string? (caar inputs)))
          inputs)
         (else (map add-input-label inputs))))
 
+(define-syntax sanitize-inputs
+  ;; This is written as a macro rather than as a 'define-inlinable' procedure
+  ;; because as of Guile 3.0.9, peval can handle (null? '()) but not
+  ;; (null? (list x y z)); that residual 'null?' test contributes to code
+  ;; bloat.
+  (syntax-rules (quote)
+    "Sanitize INPUTS by turning it into a list of name/package tuples if it's
+not already the case."
+    ((_ '()) '())
+    ((_ inputs) (maybe-add-input-labels inputs))))
+
 (define-syntax current-location-vector
   (lambda (s)
     "Like 'current-source-location' but expand to a literal vector with
-- 
2.41.0