Fix make-array transforms.

[sbcl.git] / contrib / sb-md5 / README

diff --git a/contrib/sb-md5/README b/contrib/sb-md5/README
index 9155f29..f44c306 100644 (file)
--- a/contrib/sb-md5/README
+++ b/contrib/sb-md5/README
@@ -21,11 +21,12 @@ Notes:
     ROTATE-BYTE on other platforms are welcome.
 
   * the algorithm includes an addition modulo 2^32.  This is
-    implemented here by (ab)using SB-EXT:TRULY-THE, to convince the
-    compiler to emit the low-level addition instruction.  This has the
-    desired consequences on 32-bit hardware, but may not work as one
-    might expect on 64-bit hardware, even if the overlying lisp is
-    32-bit.
+    implemented here for SBCL by compiler transforms on the high-level
+    description of this modular arithmetic, so although the code looks
+    like a naive implementation it actually compiles to the obvious
+    machine code.  The abuse of EXT:TRULY-THE was not robust and
+    turned out not to work on platforms where the underlying hardware
+    was 64-bit.
 
   * the "high-level" entry points to the md5 algorithm are
     MD5SUM-FILE, MD5SUM-STREAM and MD5SUM-SEQUENCE (despite its name,