Custom Query (1030 matches)

I built a hash table with keys that were simple cons cells of the form

(<type> . <item>)

I had a few <type>s, and lots of atomic <item>s (in particular, strings) for each <type>. The performance was very bad.

Investigation showed that ccl::compute-hash-code was returning a hash code that depended only on the <type> but not on the <item>, meaning that hash table look up was degenerating into a linear search.

Example:

(setq h (make-hash-table :test #'equal))

Then

(ccl::compute-hash-code h '(type . "foo") nil)
(ccl::compute-hash-code h '(type . "bar") nil)
(ccl::compute-hash-code h '(type . "baz") nil)
(ccl::compute-hash-code h '(type . pi) nil)
(ccl::compute-hash-code h '(type . nil) nil)

all return exactly the same results.

I was loading a matrix math package, via (ql:quickload "clem"), and got an error that the %unbox-s8 vinsin is missing. It's missing in both x8664-vinsins.lisp and x8632-vinsins.lisp. I have a fix that I'll commit to trunk soon.

To test, evaluate the following two forms. The first one errors before the fix.

(defun foo (m x)
  (declare (optimize (speed 3) (safety 0)))
  (declare (type (simple-array (signed-byte 8) *) m))
  (setf (aref m 0) x))

(let ((a (make-array 2 :element-type '(signed-byte 8))))
  (foo a -128)
  (assert (eql -128 (aref a 0)))
  (foo a 127)
  (assert (eql 127 (aref a 0)))
  (foo a 128)
  (assert (eql -128 (aref a 0))))

Under some circumstances apply is passing NIL as an optional parameter to an inlined function, instead of passing the default argument. (see attached paste from REPL)