X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fgeneric%2Fvm-tran.lisp;h=29c5c060cb3261372c50e6844ca7bb9b403a4491;hb=ace140856e6b3f92bb06597092a59753f1e59142;hp=ad74c20e18706db86d9eef41d925aa92c973e2f2;hpb=5eb97830eca716fef626c6e12429c99c9b97e3c8;p=sbcl.git

diff --git a/src/compiler/generic/vm-tran.lisp b/src/compiler/generic/vm-tran.lisp
index ad74c20..29c5c06 100644
--- a/src/compiler/generic/vm-tran.lisp
+++ b/src/compiler/generic/vm-tran.lisp
@@ -11,46 +11,49 @@
 
 (in-package "SB!C")
 
-;;; FIXME: It would be good to implement SB!XC:DEFCONSTANT, and use
-;;; use that here, so that the compiler is born knowing this value.
-;;; FIXME: Add a comment telling whether this holds for all vectors
-;;; or only for vectors based on simple arrays (non-adjustable, etc.).
-(defconstant vector-data-bit-offset
-  (* sb!vm:vector-data-offset sb!vm:word-bits))
-
-;;; We need to define these predicates, since the TYPEP source transform picks
-;;; whichever predicate was defined last when there are multiple predicates for
-;;; equivalent types.
-(def-source-transform short-float-p (x) `(single-float-p ,x))
+;;; We need to define these predicates, since the TYPEP source
+;;; transform picks whichever predicate was defined last when there
+;;; are multiple predicates for equivalent types.
+(define-source-transform short-float-p (x) `(single-float-p ,x))
 #!-long-float
-(def-source-transform long-float-p (x) `(double-float-p ,x))
+(define-source-transform long-float-p (x) `(double-float-p ,x))
 
-(def-source-transform compiled-function-p (x)
+(define-source-transform compiled-function-p (x)
   `(functionp ,x))
 
-(def-source-transform char-int (x)
+(define-source-transform char-int (x)
   `(char-code ,x))
 
 (deftransform abs ((x) (rational))
   '(if (< x 0) (- x) x))
 
 ;;; The layout is stored in slot 0.
-(def-source-transform %instance-layout (x)
+(define-source-transform %instance-layout (x)
   `(truly-the layout (%instance-ref ,x 0)))
-(def-source-transform %set-instance-layout (x val)
+(define-source-transform %set-instance-layout (x val)
   `(%instance-set ,x 0 (the layout ,val)))
 
 ;;;; character support
 
 ;;; In our implementation there are really only BASE-CHARs.
-(def-source-transform characterp (obj)
+(define-source-transform characterp (obj)
   `(base-char-p ,obj))
 
 ;;;; simplifying HAIRY-DATA-VECTOR-REF and HAIRY-DATA-VECTOR-SET
 
-(deftransform hairy-data-vector-ref ((array index) (array t) * :important t)
+(deftransform hairy-data-vector-ref ((string index) (simple-string t))
+  (let ((ctype (lvar-type string)))
+    (if (array-type-p ctype)
+	;; the other transform will kick in, so that's OK
+	(give-up-ir1-transform)
+	`(etypecase string
+	  ((simple-array character (*)) (data-vector-ref string index))
+	  ((simple-array nil (*)) (data-vector-ref string index))))))
+
+(deftransform hairy-data-vector-ref ((array index) (array t) *)
   "avoid runtime dispatch on array element type"
-  (let ((element-ctype (extract-upgraded-element-type array)))
+  (let ((element-ctype (extract-upgraded-element-type array))
+	(declared-element-ctype (extract-declared-element-type array)))
     (declare (type ctype element-ctype))
     (when (eq *wild-type* element-ctype)
       (give-up-ir1-transform
@@ -61,95 +64,114 @@
     ;; to hand-expand it ourselves.)
     (let ((element-type-specifier (type-specifier element-ctype)))
       `(multiple-value-bind (array index)
-	   ;; FIXME: All this noise should move into a
-	   ;; %DATA-VECTOR-AND-INDEX function, and there should be
-	   ;; DEFTRANSFORMs for %DATA-VECTOR-AND-INDEX to optimize the
-	   ;; function call away when the array is known to be simple,
-	   ;; and to specialize to
-	   ;; %DATA-VECTOR-AND-INDEX-IN-VECTOR-CASE when the array is
-	   ;; known to have only one dimension.
-	   (if (array-header-p array)
-	       (%with-array-data array index nil)
-	       (let ((array array))
-		 (declare (type (simple-array ,element-type-specifier 1)
-				array))
-		 (%check-bound array 0 index)
-		 (values array index)))
+	   (%data-vector-and-index array index)
 	 (declare (type (simple-array ,element-type-specifier 1) array))
-	 (data-vector-ref array index)))))
+	 ,(let ((bare-form '(data-vector-ref array index)))
+	    (if (type= element-ctype declared-element-ctype)
+		bare-form
+		`(the ,(type-specifier declared-element-ctype)
+		      ,bare-form)))))))
 
-;;; MNA: open-coded-simple-array patch
 (deftransform data-vector-ref ((array index)
                                (simple-array t))
-  (let ((array-type (continuation-type array)))
+  (let ((array-type (lvar-type array)))
     (unless (array-type-p array-type)
       (give-up-ir1-transform))
     (let ((dims (array-type-dimensions array-type)))
-      (when (and (consp dims) (= (length dims) 1))
+      (when (or (atom dims) (= (length dims) 1))
         (give-up-ir1-transform))
-      (let* ((el-type (array-type-element-type array-type))
-             (total-size (if (or (atom dims) (member '* dims))
+      (let ((el-type (array-type-specialized-element-type array-type))
+            (total-size (if (member '* dims)
                             '*
-                           (reduce #'* dims)))
-             (type-sp `(simple-array ,(type-specifier el-type)
-                        (,total-size))))
-        (if (atom dims)
-          `(let ((a (truly-the ,type-sp (%array-simp array))))
-            (data-vector-ref a index))
-          `(let ((a (truly-the ,type-sp (%array-data-vector array))))
-            (data-vector-ref a index)))))))
+                            (reduce #'* dims))))
+        `(data-vector-ref (truly-the (simple-array ,(type-specifier el-type)
+                                                   (,total-size))
+                                     (%array-data-vector array))
+                          index)))))
+
+(deftransform hairy-data-vector-set ((string index new-value)
+				     (simple-string t t))
+  (let ((ctype (lvar-type string)))
+    (if (array-type-p ctype)
+	;; the other transform will kick in, so that's OK
+	(give-up-ir1-transform)
+	`(etypecase string
+	  ((simple-array character (*))
+	   (data-vector-set string index new-value))
+	  ((simple-array nil (*))
+	   (data-vector-set string index new-value))))))
 
 (deftransform hairy-data-vector-set ((array index new-value)
 				     (array t t)
-				     *
-				     :important t)
+				     *)
   "avoid runtime dispatch on array element type"
-  (let ((element-ctype (extract-upgraded-element-type array)))
+  (let ((element-ctype (extract-upgraded-element-type array))
+	(declared-element-ctype (extract-declared-element-type array)))
     (declare (type ctype element-ctype))
     (when (eq *wild-type* element-ctype)
       (give-up-ir1-transform
        "Upgraded element type of array is not known at compile time."))
     (let ((element-type-specifier (type-specifier element-ctype)))
       `(multiple-value-bind (array index)
-	   ;; FIXME: All this noise should move into a
-	   ;; %DATA-VECTOR-AND-INDEX function, and there should be
-	   ;; DEFTRANSFORMs for %DATA-VECTOR-AND-INDEX to optimize the
-	   ;; function call away when the array is known to be simple,
-	   ;; and to specialize to
-	   ;; %DATA-VECTOR-AND-INDEX-IN-VECTOR-CASE when the array is
-	   ;; known to have only one dimension.
-	   (if (array-header-p array)
-	       (%with-array-data array index nil)
-	       (let ((array array))
-		 (declare (type (simple-array ,element-type-specifier 1)
-				array))
-		 (%check-bound array 0 index)
-		 (values array index)))
-	 (data-vector-set (truly-the (simple-array ,element-type-specifier 1)
-				     array)
-			  index
-			  new-value)))))
+	   (%data-vector-and-index array index)
+	 (declare (type (simple-array ,element-type-specifier 1) array)
+	          (type ,element-type-specifier new-value))
+	 ,(if (type= element-ctype declared-element-ctype)
+	      '(data-vector-set array index new-value)
+	      `(truly-the ,(type-specifier declared-element-ctype)
+		 (data-vector-set array index
+		  (the ,(type-specifier declared-element-ctype)
+		       new-value))))))))
 
-;;; MNA: open-coded-simple-array patch
 (deftransform data-vector-set ((array index new-value)
-			       (simple-array t t))
-  (let ((array-type (continuation-type array)))
+                               (simple-array t t))
+  (let ((array-type (lvar-type array)))
     (unless (array-type-p array-type)
       (give-up-ir1-transform))
     (let ((dims (array-type-dimensions array-type)))
-      (when (and (consp dims) (= (length dims) 1))
-	(give-up-ir1-transform))
-      (let* ((el-type (array-type-element-type array-type))
-             (total-size (if (or (atom dims) (member '* dims))
-			    '*
-                           (reduce #'* dims)))
-             (type-sp `(simple-array ,(type-specifier el-type)
-                        (,total-size))))
-        	(if (atom dims)
-	    `(let ((a (truly-the ,type-sp (%array-simp array))))
-	       (data-vector-set a index new-value))
-	    `(let ((a (truly-the ,type-sp (%array-data-vector array))))
-	       (data-vector-set a index new-value)))))))
+      (when (or (atom dims) (= (length dims) 1))
+        (give-up-ir1-transform))
+      (let ((el-type (array-type-specialized-element-type array-type))
+            (total-size (if (member '* dims)
+                            '*
+                            (reduce #'* dims))))
+        `(data-vector-set (truly-the (simple-array ,(type-specifier el-type)
+                                                   (,total-size))
+                                     (%array-data-vector array))
+                          index
+                          new-value)))))
+
+(defoptimizer (%data-vector-and-index derive-type) ((array index))
+  (let ((atype (lvar-type array)))
+    (when (array-type-p atype)
+      (values-specifier-type
+       `(values (simple-array ,(type-specifier
+                                (array-type-specialized-element-type atype))
+                              (*))
+                index)))))
+
+(deftransform %data-vector-and-index ((%array %index)
+				      (simple-array t)
+				      *)
+  ;; KLUDGE: why the percent signs?  Well, ARRAY and INDEX are
+  ;; respectively exported from the CL and SB!INT packages, which
+  ;; means that they're visible to all sorts of things.  If the
+  ;; compiler can prove that the call to ARRAY-HEADER-P, below, either
+  ;; returns T or NIL, it will delete the irrelevant branch.  However,
+  ;; user code might have got here with a variable named CL:ARRAY, and
+  ;; quite often compiler code with a variable named SB!INT:INDEX, so
+  ;; this can generate code deletion notes for innocuous user code:
+  ;; (DEFUN F (ARRAY I) (DECLARE (SIMPLE-VECTOR ARRAY)) (AREF ARRAY I))
+  ;; -- CSR, 2003-04-01
+
+  ;; We do this solely for the -OR-GIVE-UP side effect, since we want
+  ;; to know that the type can be figured out in the end before we
+  ;; proceed, but we don't care yet what the type will turn out to be.
+  (upgraded-element-type-specifier-or-give-up %array)
+
+  '(if (array-header-p %array)
+       (values (%array-data-vector %array) %index)
+       (values %array %index)))
 
 ;;; transforms for getting at simple arrays of (UNSIGNED-BYTE N) when (< N 8)
 ;;;
@@ -160,7 +182,7 @@
 #+nil
 (macrolet
     ((frob (type bits)
-       (let ((elements-per-word (truncate sb!vm:word-bits bits)))
+       (let ((elements-per-word (truncate sb!vm:n-word-bits bits)))
 	 `(progn
 	    (deftransform data-vector-ref ((vector index)
 					   (,type *))
@@ -168,7 +190,7 @@
 		   (floor index ,',elements-per-word)
 		 (ldb ,(ecase sb!vm:target-byte-order
 			 (:little-endian '(byte ,bits (* bit ,bits)))
-			 (:big-endian '(byte ,bits (- sb!vm:word-bits
+			 (:big-endian '(byte ,bits (- sb!vm:n-word-bits
 						      (* (1+ bit) ,bits)))))
 		      (%raw-bits vector (+ word sb!vm:vector-data-offset)))))
 	    (deftransform data-vector-set ((vector index new-value)
@@ -178,7 +200,7 @@
 		 (setf (ldb ,(ecase sb!vm:target-byte-order
 			       (:little-endian '(byte ,bits (* bit ,bits)))
 			       (:big-endian
-				'(byte ,bits (- sb!vm:word-bits
+				'(byte ,bits (- sb!vm:n-word-bits
 						(* (1+ bit) ,bits)))))
 			    (%raw-bits vector (+ word sb!vm:vector-data-offset)))
 		       new-value)))))))
@@ -186,47 +208,66 @@
   (frob (simple-array (unsigned-byte 2) (*)) 2)
   (frob (simple-array (unsigned-byte 4) (*)) 4))
 
-;;;; bit vector hackery
+;;;; BIT-VECTOR hackery
 
-;;; SIMPLE-BIT-VECTOR bit-array operations are transformed to a word loop that
-;;; does 32 bits at a time.
+;;; SIMPLE-BIT-VECTOR bit-array operations are transformed to a word
+;;; loop that does 32 bits at a time.
 ;;;
-;;; FIXME: This is a lot of repeatedly macroexpanded code. It should be a
-;;; function call instead. And do it with DEF-FROB instead of DOLIST.
-(dolist (x '((bit-and 32bit-logical-and)
-	     (bit-ior 32bit-logical-or)
-	     (bit-xor 32bit-logical-xor)
-	     (bit-eqv 32bit-logical-eqv)
-	     (bit-nand 32bit-logical-nand)
-	     (bit-nor 32bit-logical-nor)
-	     (bit-andc1 32bit-logical-andc1)
-	     (bit-andc2 32bit-logical-andc2)
-	     (bit-orc1 32bit-logical-orc1)
-	     (bit-orc2 32bit-logical-orc2)))
-  (destructuring-bind (bitfun wordfun) x
-    (deftransform bitfun
-		  ((bit-array-1 bit-array-2 result-bit-array)
-		   '(simple-bit-vector simple-bit-vector simple-bit-vector) '*
-		   :eval-name t :node node :policy (>= speed space))
-      `(progn
-	 ,@(unless (policy node (zerop safety))
-	     '((unless (= (length bit-array-1) (length bit-array-2)
-			  (length result-bit-array))
-		 (error "Argument and/or result bit arrays are not the same length:~
+;;; FIXME: This is a lot of repeatedly macroexpanded code. It should
+;;; be a function call instead.
+(macrolet ((def (bitfun wordfun)
+             `(deftransform ,bitfun ((bit-array-1 bit-array-2 result-bit-array)
+                                     (simple-bit-vector
+				      simple-bit-vector
+				      simple-bit-vector)
+				     *
+                                     :node node :policy (>= speed space))
+                `(progn
+                   ,@(unless (policy node (zerop safety))
+                             '((unless (= (length bit-array-1)
+					  (length bit-array-2)
+                                          (length result-bit-array))
+                                 (error "Argument and/or result bit arrays are not the same length:~
 			 ~%  ~S~%  ~S  ~%  ~S"
-			bit-array-1 bit-array-2 result-bit-array))))
-	 (do ((index sb!vm:vector-data-offset (1+ index))
-	      (end (+ sb!vm:vector-data-offset
-		      (truncate (the index
-				     (+ (length bit-array-1)
-					sb!vm:word-bits -1))
-				sb!vm:word-bits))))
-	     ((= index end) result-bit-array)
-	   (declare (optimize (speed 3) (safety 0))
-		    (type index index end))
-	   (setf (%raw-bits result-bit-array index)
-		 (,wordfun (%raw-bits bit-array-1 index)
-			   (%raw-bits bit-array-2 index))))))))
+                                        bit-array-1
+					bit-array-2
+					result-bit-array))))
+		  (let ((length (length result-bit-array)))
+		    (if (= length 0)
+			;; We avoid doing anything to 0-length
+			;; bit-vectors, or rather, the memory that
+			;; follows them. Other divisible-by-32 cases
+			;; are handled by the (1- length), below.
+			;; CSR, 2002-04-24
+			result-bit-array
+			(do ((index sb!vm:vector-data-offset (1+ index))
+			     (end-1 (+ sb!vm:vector-data-offset
+				       ;; bit-vectors of length 1-32
+				       ;; need precisely one (SETF
+				       ;; %RAW-BITS), done here in the
+				       ;; epilogue. - CSR, 2002-04-24
+				       (truncate (truly-the index (1- length))
+						 sb!vm:n-word-bits))))
+			    ((= index end-1)
+			     (setf (%raw-bits result-bit-array index)
+				   (,',wordfun (%raw-bits bit-array-1 index)
+					       (%raw-bits bit-array-2 index)))
+			     result-bit-array)
+			  (declare (optimize (speed 3) (safety 0))
+				   (type index index end-1))
+			  (setf (%raw-bits result-bit-array index)
+				(,',wordfun (%raw-bits bit-array-1 index)
+					    (%raw-bits bit-array-2 index))))))))))
+ (def bit-and word-logical-and)
+ (def bit-ior word-logical-or)
+ (def bit-xor word-logical-xor)
+ (def bit-eqv word-logical-eqv)
+ (def bit-nand word-logical-nand)
+ (def bit-nor word-logical-nor)
+ (def bit-andc1 word-logical-andc1)
+ (def bit-andc2 word-logical-andc2)
+ (def bit-orc1 word-logical-orc1)
+ (def bit-orc2 word-logical-orc2))
 
 (deftransform bit-not
 	      ((bit-array result-bit-array)
@@ -239,46 +280,191 @@
 	     (error "Argument and result bit arrays are not the same length:~
 	     	     ~%  ~S~%  ~S"
 		    bit-array result-bit-array))))
-     (do ((index sb!vm:vector-data-offset (1+ index))
-	  (end (+ sb!vm:vector-data-offset
-		  (truncate (the index
-				 (+ (length bit-array)
-				    (1- sb!vm:word-bits)))
-			    sb!vm:word-bits))))
-	 ((= index end) result-bit-array)
-       (declare (optimize (speed 3) (safety 0))
-		(type index index end))
-       (setf (%raw-bits result-bit-array index)
-	     (32bit-logical-not (%raw-bits bit-array index))))))
+    (let ((length (length result-bit-array)))
+      (if (= length 0)
+	  ;; We avoid doing anything to 0-length bit-vectors, or
+	  ;; rather, the memory that follows them. Other
+	  ;; divisible-by-32 cases are handled by the (1- length),
+	  ;; below.  CSR, 2002-04-24
+	  result-bit-array
+	  (do ((index sb!vm:vector-data-offset (1+ index))
+	       (end-1 (+ sb!vm:vector-data-offset
+			 ;; bit-vectors of length 1-32 need precisely
+			 ;; one (SETF %RAW-BITS), done here in the
+			 ;; epilogue. - CSR, 2002-04-24
+			 (truncate (truly-the index (1- length))
+				   sb!vm:n-word-bits))))
+	      ((= index end-1)
+	       (setf (%raw-bits result-bit-array index)
+		     (word-logical-not (%raw-bits bit-array index)))
+	       result-bit-array)
+	    (declare (optimize (speed 3) (safety 0))
+		     (type index index end-1))
+	    (setf (%raw-bits result-bit-array index)
+		  (word-logical-not (%raw-bits bit-array index))))))))
+
+(deftransform bit-vector-= ((x y) (simple-bit-vector simple-bit-vector))
+  `(and (= (length x) (length y))
+        (let ((length (length x)))
+	  (or (= length 0)
+	      (do* ((i sb!vm:vector-data-offset (+ i 1))
+		    (end-1 (+ sb!vm:vector-data-offset
+			      (floor (1- length) sb!vm:n-word-bits))))
+		   ((= i end-1)
+		    (let* ((extra (mod length sb!vm:n-word-bits))
+			   (mask (1- (ash 1 extra)))
+			   (numx
+			    (logand
+			     (ash mask
+				  ,(ecase sb!c:*backend-byte-order*
+				     (:little-endian 0)
+				     (:big-endian
+				      '(- sb!vm:n-word-bits extra))))
+			     (%raw-bits x i)))
+			   (numy
+			    (logand
+			     (ash mask
+				  ,(ecase sb!c:*backend-byte-order*
+				     (:little-endian 0)
+				     (:big-endian
+				      '(- sb!vm:n-word-bits extra))))
+			     (%raw-bits y i))))
+		      (declare (type (integer 0 31) extra)
+			       (type sb!vm:word mask numx numy))
+		      (= numx numy)))
+		(declare (type index i end-1))
+		(let ((numx (%raw-bits x i))
+		      (numy (%raw-bits y i)))
+		  (declare (type sb!vm:word numx numy))
+		  (unless (= numx numy)
+		    (return nil))))))))
+
+(deftransform count ((sequence item) (simple-bit-vector bit) *
+                     :policy (>= speed space))
+  `(let ((length (length sequence)))
+    (if (zerop length)
+        0
+        (do ((index sb!vm:vector-data-offset (1+ index))
+             (count 0)
+             (end-1 (+ sb!vm:vector-data-offset
+                       (truncate (truly-the index (1- length))
+                                 sb!vm:n-word-bits))))
+            ((= index end-1)
+             (let* ((extra (mod length sb!vm:n-word-bits))
+		    (mask (1- (ash 1 extra)))
+		    (bits (logand (ash mask
+				       ,(ecase sb!c:*backend-byte-order*
+					       (:little-endian 0)
+					       (:big-endian
+						'(- sb!vm:n-word-bits extra))))
+				  (%raw-bits sequence index))))
+               (declare (type sb!vm:word mask bits))
+               ;; could consider LOGNOT for the zero case instead of
+               ;; doing the subtraction...
+               (incf count ,(if (constant-lvar-p item)
+                                (if (zerop (lvar-value item))
+                                    '(- extra (logcount bits))
+                                    '(logcount bits))
+                                '(if (zerop item)
+                                     (- extra (logcount bits))
+                                     (logcount bits))))))
+          (declare (type index index count end-1)
+		   (optimize (speed 3) (safety 0)))
+          (incf count ,(if (constant-lvar-p item)
+                           (if (zerop (lvar-value item))
+                               '(- sb!vm:n-word-bits (logcount (%raw-bits sequence index)))
+                               '(logcount (%raw-bits sequence index)))
+                           '(if (zerop item)
+                             (- sb!vm:n-word-bits (logcount (%raw-bits sequence index)))
+                             (logcount (%raw-bits sequence index)))))))))
+
+(deftransform fill ((sequence item) (simple-bit-vector bit) *
+		    :policy (>= speed space))
+  (let ((value (if (constant-lvar-p item)
+		   (if (= (lvar-value item) 0)
+		       0
+		       #.(1- (ash 1 32)))
+		   `(if (= item 0) 0 #.(1- (ash 1 32))))))
+    `(let ((length (length sequence))
+	   (value ,value))
+       (if (= length 0)
+	   sequence
+	   (do ((index sb!vm:vector-data-offset (1+ index))
+		(end-1 (+ sb!vm:vector-data-offset
+			  ;; bit-vectors of length 1-32 need precisely
+			  ;; one (SETF %RAW-BITS), done here in the
+			  ;; epilogue. - CSR, 2002-04-24
+			  (truncate (truly-the index (1- length))
+				    sb!vm:n-word-bits))))
+	       ((= index end-1)
+		(setf (%raw-bits sequence index) value)
+		sequence)
+	     (declare (optimize (speed 3) (safety 0))
+		      (type index index end-1))
+	     (setf (%raw-bits sequence index) value))))))
+
+(deftransform fill ((sequence item) (simple-base-string base-char) *
+		    :policy (>= speed space))
+  (let ((value (if (constant-lvar-p item)
+		   (let* ((char (lvar-value item))
+			  (code (sb!xc:char-code char)))
+		     (logior code (ash code 8) (ash code 16) (ash code 24)))
+		   `(let ((code (sb!xc:char-code item)))
+		     (logior code (ash code 8) (ash code 16) (ash code 24))))))
+    `(let ((length (length sequence))
+	   (value ,value))
+      (multiple-value-bind (times rem)
+	  (truncate length 4)
+	(do ((index sb!vm:vector-data-offset (1+ index))
+	     (end (+ times sb!vm:vector-data-offset)))
+	    ((= index end)
+	     (let ((place (* times 4)))
+	       (declare (fixnum place))
+	       (dotimes (j rem sequence)
+		 (declare (index j))
+		 (setf (schar sequence (the index (+ place j))) item))))
+	  (declare (optimize (speed 3) (safety 0))
+		   (type index index))
+	  (setf (%raw-bits sequence index) value))))))
 
-;;;; primitive translator for BYTE-BLT
+;;;; %BYTE-BLT
 
-(def-primitive-translator byte-blt (src src-start dst dst-start dst-end)
-  `(let ((src ,src)
-	 (src-start (* ,src-start sb!vm:byte-bits))
-	 (dst ,dst)
-	 (dst-start (* ,dst-start sb!vm:byte-bits))
-	 (dst-end (* ,dst-end sb!vm:byte-bits)))
-     (let ((length (- dst-end dst-start)))
-       (etypecase src
-	 (system-area-pointer
-	  (etypecase dst
-	    (system-area-pointer
-	     (system-area-copy src src-start dst dst-start length))
-	    ((simple-unboxed-array (*))
-	     (copy-from-system-area src src-start
-				    dst (+ dst-start ,vector-data-bit-offset)
-				    length))))
-	 ((simple-unboxed-array (*))
-	  (etypecase dst
-	    (system-area-pointer
-	     (copy-to-system-area src (+ src-start ,vector-data-bit-offset)
-				  dst dst-start
-				  length))
-	    ((simple-unboxed-array (*))
-	     (bit-bash-copy src (+ src-start ,vector-data-bit-offset)
-			    dst (+ dst-start ,vector-data-bit-offset)
-			    length))))))))
+;;; FIXME: The old CMU CL code used various COPY-TO/FROM-SYSTEM-AREA
+;;; stuff (with all the associated bit-index cruft and overflow
+;;; issues) even for byte moves. In SBCL, we're converting to byte
+;;; moves as problems are discovered with the old code, and this is
+;;; currently (ca. sbcl-0.6.12.30) the main interface for code in
+;;; SB!KERNEL and SB!SYS (e.g. i/o code). It's not clear that it's the
+;;; ideal interface, though, and it probably deserves some thought.
+(deftransform %byte-blt ((src src-start dst dst-start dst-end)
+			 ((or (simple-unboxed-array (*)) system-area-pointer)
+			  index
+			  (or (simple-unboxed-array (*)) system-area-pointer)
+			  index
+			  index))
+  ;; FIXME: CMU CL had a hairier implementation of this (back when it
+  ;; was still called (%PRIMITIVE BYTE-BLT). It had the small problem
+  ;; that it didn't work for large (>16M) values of SRC-START or
+  ;; DST-START. However, it might have been more efficient. In
+  ;; particular, I don't really know how much the foreign function
+  ;; call costs us here. My guess is that if the overhead is
+  ;; acceptable for SQRT and COS, it's acceptable here, but this
+  ;; should probably be checked. -- WHN
+  '(flet ((sapify (thing)
+	    (etypecase thing
+	      (system-area-pointer thing)
+	      ;; FIXME: The code here rather relies on the simple
+	      ;; unboxed array here having byte-sized entries. That
+	      ;; should be asserted explicitly, I just haven't found
+	      ;; a concise way of doing it. (It would be nice to
+	      ;; declare it in the DEFKNOWN too.)
+	      ((simple-unboxed-array (*)) (vector-sap thing)))))
+     (declare (inline sapify))
+     (without-gcing
+      (memmove (sap+ (sapify dst) dst-start)
+	       (sap+ (sapify src) src-start)
+	       (- dst-end dst-start)))
+     (values)))
 
 ;;;; transforms for EQL of floating point values
 
@@ -289,3 +475,72 @@
   '(and (= (double-float-low-bits x) (double-float-low-bits y))
 	(= (double-float-high-bits x) (double-float-high-bits y))))
 
+
+;;;; modular functions
+(define-good-modular-fun logand)
+(define-good-modular-fun logior)
+;;; FIXME: XOR? ANDC1, ANDC2?  -- CSR, 2003-09-16
+
+(macrolet
+    ((def (name width)
+	 `(progn
+	    (defknown ,name (integer (integer 0)) (unsigned-byte ,width)
+		      (foldable flushable movable))
+	    (define-modular-fun-optimizer ash ((integer count) :width width)
+	      (when (and (<= width 32)
+			 (constant-lvar-p count) ;?
+			 (plusp (lvar-value count)))
+		(cut-to-width integer width)
+		',name))
+	    (setf (gethash ',name *modular-versions*) `(ash ,',width)))))
+  #!-alpha (def sb!vm::ash-left-mod32 32)
+  #!+alpha (def sb!vm::ash-left-mod64 64))
+
+;;; There are two different ways the multiplier can be recoded. The
+;;; more obvious is to shift X by the correct amount for each bit set
+;;; in Y and to sum the results. But if there is a string of bits that
+;;; are all set, you can add X shifted by one more then the bit
+;;; position of the first set bit and subtract X shifted by the bit
+;;; position of the last set bit. We can't use this second method when
+;;; the high order bit is bit 31 because shifting by 32 doesn't work
+;;; too well.
+(defun ub32-strength-reduce-constant-multiply (arg num)
+  (declare (type (unsigned-byte 32) num))
+  (let ((adds 0) (shifts 0)
+	(result nil) first-one)
+    (labels ((add (next-factor)
+	       (setf result
+		     (if result
+                         (progn (incf adds) `(+ ,result ,next-factor))
+                         next-factor))))
+      (declare (inline add))
+      (dotimes (bitpos 32)
+	(if first-one
+	    (when (not (logbitp bitpos num))
+	      (add (if (= (1+ first-one) bitpos)
+		       ;; There is only a single bit in the string.
+		       (progn (incf shifts) `(ash ,arg ,first-one))
+		       ;; There are at least two.
+		       (progn
+			 (incf adds)
+			 (incf shifts 2)
+			 `(- (ash ,arg ,bitpos)
+			     (ash ,arg ,first-one)))))
+	      (setf first-one nil))
+	    (when (logbitp bitpos num)
+	      (setf first-one bitpos))))
+      (when first-one
+	(cond ((= first-one 31))
+	      ((= first-one 30) (incf shifts) (add `(ash ,arg 30)))
+	      (t
+	       (incf shifts 2)
+	       (incf adds)
+	       (add `(- (ash ,arg 31)
+			(ash ,arg ,first-one)))))
+	(incf shifts)
+	(add `(ash ,arg 31))))
+    (values (if (plusp adds)
+                `(logand ,result #.(1- (ash 1 32))) ; using modular arithmetic
+                result)
+            adds
+            shifts)))