math: Inline operations for performance improvements.

1 files changed, 28 insertions, 2 deletions

diff --git a/chickadee/math.scm b/chickadee/math.scm
index 753f70d..3bcda52 100644
--- a/chickadee/math.scm
+++ b/chickadee/math.scm
@@ -16,11 +16,37 @@
 ;;; <http://www.gnu.org/licenses/>.
 
 (define-module (chickadee math)
-  #:export (clamp))
+  #:export (square
+            clamp
+            min
+            max)
+  #:replace (min max))
 
-(define (clamp min max x)
+(define-inlinable (square x)
+  (* x x))
+
+(define-inlinable (clamp min max x)
   "Restrict X to the range defined by MIN and MAX. Assumes that MIN is
 actually less than MAX."
   (cond ((< x min) min)
         ((> x max) max)
         (else x)))
+
+;; Some macro trickery to inline calls to min/max with 2 arguments.
+;; We often call min/max on floating point values, so inlining such
+;; calls allows the compiler to unbox many of these operations,
+;; reducing allocation.
+(define-syntax min
+  (syntax-rules ()
+    ((_ a b)
+     (if (< a b) a b))
+    ((_ a b ...)
+     (let ((m (min b ...)))
+       (if (< a m) a m)))))
+
+(define-syntax max
+  (syntax-rules ()
+    ((_ a b) (if (> a b) a b))
+    ((_ a b ...)
+     (let ((m (max b ...)))
+       (if (> a m) a m)))))