-;;;; simple string transforms
-;;;;
-;;;; Note: CMU CL had more of these, including transforms for
-;;;; functions which cons. In SBCL, we've gotten rid of the transforms
-;;;; for functions which cons, since our GC overhead is sufficiently
-;;;; large that it doesn't seem worth it to try to economize on
-;;;; function call overhead or on the overhead of runtime type
-;;;; dispatch in AREF.
-
-;;; FIXME: Shouldn't we be testing for legality of
-;;; * START1, START2, END1, and END2 indices?
-;;; * size of copied string relative to destination string?
-;;; (Either there should be tests conditional on SAFETY>=SPEED, or
-;;; the transform should be conditional on SPEED>SAFETY.)
-;;;
-;;; FIXME: Also, the transform should probably be dependent on
-;;; SPEED>SPACE.
-(deftransform replace ((string1 string2 &key (start1 0) (start2 0)
- end1 end2)
- (simple-string simple-string &rest t))
- `(locally
- (declare (optimize (safety 0)))
- (bit-bash-copy string2
- (the index
- (+ (the index (* start2 sb!vm:byte-bits))
- ,vector-data-bit-offset))
- string1
- (the index
- (+ (the index (* start1 sb!vm:byte-bits))
- ,vector-data-bit-offset))
- (the index
- (* (min (the index (- (or end1 (length string1))
- start1))
- (the index (- (or end2 (length string2))
- start2)))
- sb!vm:byte-bits)))
- string1))
-\f