;;;; implementation-dependent transforms ;;;; This software is part of the SBCL system. See the README file for ;;;; more information. ;;;; ;;;; This software is derived from the CMU CL system, which was ;;;; written at Carnegie Mellon University and released into the ;;;; public domain. The software is in the public domain and is ;;;; provided with absolutely no warranty. See the COPYING and CREDITS ;;;; files for more information. (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)) #!-long-float (def-source-transform long-float-p (x) `(double-float-p ,x)) (def-source-transform compiled-function-p (x) `(functionp ,x)) (def-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) `(truly-the layout (%instance-ref ,x 0))) (def-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) `(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) "avoid runtime dispatch on array element type" (let ((element-ctype (extract-upgraded-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.")) ;; (The expansion here is basically a degenerate case of ;; WITH-ARRAY-DATA. Since WITH-ARRAY-DATA is implemented as a ;; macro, and macros aren't expanded in transform output, we have ;; 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))) (declare (type (simple-array ,element-type-specifier 1) array)) (data-vector-ref array index))))) (deftransform data-vector-ref ((array index) (simple-array t)) (let ((array-type (continuation-type array))) (unless (array-type-p array-type) (give-up-ir1-transform)) (let ((dims (array-type-dimensions array-type))) (when (or (atom dims) (= (length dims) 1)) (give-up-ir1-transform)) (let ((el-type (array-type-element-type array-type)) (total-size (if (member '* dims) '* (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 ((array index new-value) (array t t) * :important t) "avoid runtime dispatch on array element type" (let ((element-ctype (extract-upgraded-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))))) (deftransform data-vector-set ((array index new-value) (simple-array t t)) (let ((array-type (continuation-type array))) (unless (array-type-p array-type) (give-up-ir1-transform)) (let ((dims (array-type-dimensions array-type))) (when (or (atom dims) (= (length dims) 1)) (give-up-ir1-transform)) (let ((el-type (array-type-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))))) ;;; transforms for getting at simple arrays of (UNSIGNED-BYTE N) when (< N 8) ;;; ;;; FIXME: In CMU CL, these were commented out with #+NIL. Why? Should ;;; we fix them or should we delete them? (Perhaps these definitions ;;; predate the various DATA-VECTOR-REF-FOO VOPs which have ;;; (:TRANSLATE DATA-VECTOR-REF), and are redundant now?) #+nil (macrolet ((frob (type bits) (let ((elements-per-word (truncate sb!vm:word-bits bits))) `(progn (deftransform data-vector-ref ((vector index) (,type *)) `(multiple-value-bind (word bit) (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 (* (1+ bit) ,bits))))) (%raw-bits vector (+ word sb!vm:vector-data-offset))))) (deftransform data-vector-set ((vector index new-value) (,type * *)) `(multiple-value-bind (word bit) (floor index ,',elements-per-word) (setf (ldb ,(ecase sb!vm:target-byte-order (:little-endian '(byte ,bits (* bit ,bits))) (:big-endian '(byte ,bits (- sb!vm:word-bits (* (1+ bit) ,bits))))) (%raw-bits vector (+ word sb!vm:vector-data-offset))) new-value))))))) (frob simple-bit-vector 1) (frob (simple-array (unsigned-byte 2) (*)) 2) (frob (simple-array (unsigned-byte 4) (*)) 4)) ;;;; bit vector hackery ;;; 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:~ ~% ~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)))))))) (deftransform bit-not ((bit-array result-bit-array) (simple-bit-vector simple-bit-vector) * :node node :policy (>= speed space)) `(progn ,@(unless (policy node (zerop safety)) '((unless (= (length bit-array) (length result-bit-array)) (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)))))) ;;;; %BYTE-BLT ;;; 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))) nil)) ;;;; transforms for EQL of floating point values (deftransform eql ((x y) (single-float single-float)) '(= (single-float-bits x) (single-float-bits y))) (deftransform eql ((x y) (double-float double-float)) '(and (= (double-float-low-bits x) (double-float-low-bits y)) (= (double-float-high-bits x) (double-float-high-bits y))))