Changeset 14231

Timestamp:

Sep 1, 2010, 6:37:05 PM (14 years ago)

Author:

R. Matthew Emerson

Message:

Open-code ASH in cases where the integer is a fixnum, and the shift
count is known to be a sufficiently small positive integer.

File:

• trunk/source/compiler/nx1.lisp (modified) (1 diff)

trunk/source/compiler/nx1.lisp

@@ -2255 +2255 @@
                        (nx1-form num)
                        (nx1-form amt)))
+          ((fixnump num)
+           (let* ((field-width (1+ (integer-length num)))
+                  ;; num fits in a `(signed-byte ,field-width)
+                  (max-shift (- (1+ maxbits) field-width)))
+             (if (nx-form-typep amt `(mod ,(1+ max-shift)) env)
+               (nx1-form `(%ilsl ,amt ,num))
+               (nx1-treat-as-call call))))
           (t (nx1-treat-as-call call)))))