X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Ftarget-hash-table.lisp;h=cb9c502eb24c43219975aa99376a06e57b75dc2b;hb=98a76d4426660876dec6649b1e228d2e5b47f579;hp=e5b5761815945696eb228f149a53d17003148634;hpb=b6aa15328871678a3475e82c150b251dffb49ba1;p=sbcl.git

diff --git a/src/code/target-hash-table.lisp b/src/code/target-hash-table.lisp
index e5b5761..cb9c502 100644
--- a/src/code/target-hash-table.lisp
+++ b/src/code/target-hash-table.lisp
@@ -140,7 +140,18 @@
 	   ;; boxing.
 	   (rehash-threshold (float rehash-threshold 1.0))
 	   (size+1 (1+ size))		; The first element is not usable.
-	   (scaled-size (round (/ (float size+1) rehash-threshold)))
+           ;; KLUDGE: The most natural way of expressing the below is
+           ;; (round (/ (float size+1) rehash-threshold)), and indeed
+           ;; it was expressed like that until 0.7.0. However,
+           ;; MAKE-HASH-TABLE is called very early in cold-init, and
+           ;; the SPARC has no primitive instructions for rounding,
+           ;; but only for truncating; therefore, we fudge this issue
+           ;; a little. The other uses of truncate, below, similarly
+           ;; used to be round. -- CSR, 2002-10-01
+	   ;;
+	   ;; Note that this has not yet been audited for
+	   ;; correctness. It just seems to work. -- CSR, 2002-11-02
+	   (scaled-size (truncate (/ (float size+1) rehash-threshold)))
 	   (length (almost-primify (max scaled-size
 					(1+ +min-hash-table-size+))))
 	   (index-vector (make-array length
@@ -165,6 +176,14 @@
 		   :hash-vector (unless (eq test 'eq)
 				  (make-array size+1
 					      :element-type '(unsigned-byte 32)
+					      ;; as explained by pmai on
+					      ;; openprojects #lisp IRC
+					      ;; 2002-07-30: #x80000000 is
+					      ;; bigger than any possible nonEQ
+					      ;; hash value, and thus indicates
+					      ;; an empty slot; and EQ hash
+					      ;; tables don't use
+					      ;; HASH-TABLE-HASH-VECTOR
 					      :initial-element #x80000000)))))
       (declare (type index size+1 scaled-size length))
       ;; Set up the free list, all free. These lists are 0 terminated.
@@ -224,7 +243,7 @@
 	      (fixnum
 	       (+ rehash-size old-size))
 	      (float
-	       (the index (round (* rehash-size old-size)))))))
+	       (the index (truncate (* rehash-size old-size)))))))
 	 (new-kv-vector (make-array (* 2 new-size)
 				    :initial-element +empty-ht-slot+))
 	 (new-next-vector (make-array new-size
@@ -236,7 +255,7 @@
 					:initial-element #x80000000)))
 	 (old-index-vector (hash-table-index-vector table))
 	 (new-length (almost-primify
-		      (round (/ (float new-size)
+		      (truncate (/ (float new-size)
 				(hash-table-rehash-threshold table)))))
 	 (new-index-vector (make-array new-length
 				       :element-type '(unsigned-byte 32)