X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fseqtran.lisp;h=5e4de7fb7a68d8a3ca325f7a38d883c919c7b1fa;hb=33a45339444f8418c8c537c43d59fc3d5ea3098b;hp=68aa5b376e16ddd9acb7f71833d3f0cc31bd75d0;hpb=dd92bd1d2fff942e6a38542364be21fa256cb4c0;p=sbcl.git

diff --git a/src/compiler/seqtran.lisp b/src/compiler/seqtran.lisp
index 68aa5b3..5e4de7f 100644
--- a/src/compiler/seqtran.lisp
+++ b/src/compiler/seqtran.lisp
@@ -776,7 +776,7 @@
                (end1 (or end1 len1))
                (end2 (or end2 len2))
                (replace-len (min (- end1 start1) (- end2 start2))))
-          ,(unless (policy node (= safety 0))
+          ,(unless (policy node (= insert-array-bounds-checks 0))
              `(progn
                 (unless (<= 0 start1 end1 len1)
                   (sequence-bounding-indices-bad-error seq1 start1 end1))
@@ -1086,6 +1086,13 @@
 ;;; Only handle the simple result type cases. If somebody does (CONCATENATE
 ;;; '(STRING 6) ...) their code won't be optimized, but nobody does that in
 ;;; practice.
+;;;
+;;; Limit full open coding based on length of constant sequences. Default
+;;; value is chosen so that other parts of to compiler (constraint propagation
+;;; mainly) won't go nonlinear too badly. It's not an exact number -- but
+;;; in the right ballpark.
+(defvar *concatenate-open-code-limit* 129)
+
 (deftransform concatenate ((result-type &rest lvars)
                            ((constant-arg
                              (member string simple-string base-string simple-base-string))
@@ -1122,6 +1129,7 @@
           `(apply
             (lambda ,vars
               (declare (ignorable ,@vars))
+              (declare (optimize (insert-array-bounds-checks 0)))
               (let* ((.length. (+ ,@lengths))
                      (.pos. 0)
                      (.string. (make-string .length. :element-type ',element-type)))
@@ -1129,13 +1137,19 @@
                          (muffle-conditions compiler-note))
                 ,@(loop for value in lvar-values
                         for var in vars
-                        collect (if (stringp value)
+                        collect (if (and (stringp value)
+                                         (< (length value) *concatenate-open-code-limit*))
                                     ;; Fold the array reads for constant arguments
                                     `(progn
                                        ,@(loop for c across value
-                                               collect `(setf (aref .string.
-                                                                    .pos.) ,c)
-                                               collect `(incf .pos.)))
+                                               for i from 0
+                                               collect
+                                               ;; Without truly-the we get massive numbers
+                                               ;; of pointless error traps.
+                                                  `(setf (aref .string.
+                                                               (truly-the index (+ .pos. ,i)))
+                                                         ,c))
+                                       (incf .pos. ,(length value)))
                                     `(sb!impl::string-dispatch
                                          (#!+sb-unicode
                                           (simple-array character (*))