X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Ffloat-tran.lisp;h=dc2615f6d87cdff83b1c76fb22b38b30ba08acdb;hb=90ca09b75fbc3b63b2f7d09c67b04b866dd783f6;hp=107df29f494ae043779d40ca25e9db7b516a6ed1;hpb=334af30b26555f0bf706f7157b399bdbd4fad548;p=sbcl.git diff --git a/src/compiler/float-tran.lisp b/src/compiler/float-tran.lisp index 107df29..dc2615f 100644 --- a/src/compiler/float-tran.lisp +++ b/src/compiler/float-tran.lisp @@ -30,18 +30,6 @@ (deftransform %double-float ((n) (double-float) * :when :both) 'n) -;;; not strictly float functions, but primarily useful on floats: -(macrolet ((frob (fun ufun) - `(progn - (defknown ,ufun (real) integer (movable foldable flushable)) - (deftransform ,fun ((x &optional by) - (* &optional - (constant-argument (member 1)))) - '(let ((res (,ufun x))) - (values res (- x res))))))) - (frob truncate %unary-truncate) - (frob round %unary-round)) - ;;; RANDOM (macrolet ((frob (fun type) `(deftransform random ((num &optional state) @@ -166,8 +154,7 @@ (deftransform scale-float ((f ex) (single-float *) * :when :both) (if (and #!+x86 t #!-x86 nil (csubtypep (continuation-type ex) - (specifier-type '(signed-byte 32))) - (not (byte-compiling))) + (specifier-type '(signed-byte 32)))) '(coerce (%scalbn (coerce f 'double-float) ex) 'single-float) '(scale-single-float f ex))) @@ -178,9 +165,43 @@ '(%scalbn f ex) '(scale-double-float f ex))) +;;; What is the CROSS-FLOAT-INFINITY-KLUDGE? +;;; +;;; SBCL's own implementation of floating point supports floating +;;; point infinities. Some of the old CMU CL :PROPAGATE-FLOAT-TYPE and +;;; :PROPAGATE-FUN-TYPE code, like the DEFOPTIMIZERs below, uses this +;;; floating point support. Thus, we have to avoid running it on the +;;; cross-compilation host, since we're not guaranteed that the +;;; cross-compilation host will support floating point infinities. +;;; +;;; If we wanted to live dangerously, we could conditionalize the code +;;; with #+(OR SBCL SB-XC) instead. That way, if the cross-compilation +;;; host happened to be SBCL, we'd be able to run the infinity-using +;;; code. Pro: +;;; * SBCL itself gets built with more complete optimization. +;;; Con: +;;; * You get a different SBCL depending on what your cross-compilation +;;; host is. +;;; So far the pros and cons seem seem to be mostly academic, since +;;; AFAIK (WHN 2001-08-28) the propagate-foo-type optimizations aren't +;;; actually important in compiling SBCL itself. If this changes, then +;;; we have to decide: +;;; * Go for simplicity, leaving things as they are. +;;; * Go for performance at the expense of conceptual clarity, +;;; using #+(OR SBCL SB-XC) and otherwise leaving the build +;;; process as is. +;;; * Go for performance at the expense of build time, using +;;; #+(OR SBCL SB-XC) and also making SBCL do not just +;;; make-host-1.sh and make-host-2.sh, but a third step +;;; make-host-3.sh where it builds itself under itself. (Such a +;;; 3-step build process could also help with other things, e.g. +;;; using specialized arrays to represent debug information.) +;;; * Rewrite the code so that it doesn't depend on unportable +;;; floating point infinities. + ;;; optimizers for SCALE-FLOAT. If the float has bounds, new bounds ;;; are computed for the result, if possible. -#!+sb-propagate-float-type +#-sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (progn (defun scale-float-derive-type-aux (f ex same-arg) @@ -247,12 +268,12 @@ ;;; Do some stuff to recognize when the loser is doing mixed float and ;;; rational arithmetic, or different float types, and fix it up. If -;;; we don't, he won't even get so much as an efficency note. +;;; we don't, he won't even get so much as an efficiency note. (deftransform float-contagion-arg1 ((x y) * * :defun-only t :node node) - `(,(continuation-function-name (basic-combination-fun node)) + `(,(continuation-fun-name (basic-combination-fun node)) (float x y) y)) (deftransform float-contagion-arg2 ((x y) * * :defun-only t :node node) - `(,(continuation-function-name (basic-combination-fun node)) + `(,(continuation-fun-name (basic-combination-fun node)) x (float y x))) (dolist (x '(+ * / -)) @@ -290,7 +311,7 @@ ;;; Derive the result to be float for argument types in the ;;; appropriate domain. -#!-sb-propagate-fun-type +#+sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (dolist (stuff '((asin (real -1.0 1.0)) (acos (real -1.0 1.0)) (acosh (real 1.0)) @@ -306,7 +327,7 @@ type) (specifier-type 'float))))))) -#!-sb-propagate-fun-type +#+sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (defoptimizer (log derive-type) ((x &optional y)) (when (and (csubtypep (continuation-type x) (specifier-type '(real 0.0))) @@ -394,6 +415,7 @@ (cos %cos %cos-quick) (tan %tan %tan-quick))) (destructuring-bind (name prim prim-quick) stuff + (declare (ignorable prim-quick)) (deftransform name ((x) '(single-float) '* :eval-name t) #!+x86 (cond ((csubtypep (continuation-type x) (specifier-type '(single-float @@ -466,11 +488,7 @@ (float pi x) (float 0 x))) -#!+(or sb-propagate-float-type sb-propagate-fun-type) -(progn - ;;; The number is of type REAL. -#!-sb-fluid (declaim (inline numeric-type-real-p)) (defun numeric-type-real-p (type) (and (numeric-type-p type) (eq (numeric-type-complexp type) :real))) @@ -483,9 +501,7 @@ (list (coerce (car bound) type)) (coerce bound type)))) -) ; PROGN - -#!+sb-propagate-fun-type +#-sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (progn ;;;; optimizers for elementary functions @@ -1020,7 +1036,7 @@ :complexp :real :low (numeric-type-low type) :high (numeric-type-high type)))))) -#!+(or sb-propagate-fun-type sb-propagate-float-type) +#-sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (defoptimizer (realpart derive-type) ((num)) (one-arg-derive-type num #'realpart-derive-type-aux #'realpart)) (defun imagpart-derive-type-aux (type) @@ -1044,7 +1060,7 @@ :complexp :real :low (numeric-type-low type) :high (numeric-type-high type)))))) -#!+(or sb-propagate-fun-type sb-propagate-float-type) +#-sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (defoptimizer (imagpart derive-type) ((num)) (one-arg-derive-type num #'imagpart-derive-type-aux #'imagpart)) @@ -1086,7 +1102,7 @@ :complex)))) (specifier-type 'complex))) -#!+(or sb-propagate-fun-type sb-propagate-float-type) +#-sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (defoptimizer (complex derive-type) ((re &optional im)) (if im (two-arg-derive-type re im #'complex-derive-type-aux-2 #'complex) @@ -1169,7 +1185,7 @@ ;;; possible answer. This gets around the problem of doing range ;;; reduction correctly but still provides useful results when the ;;; inputs are union types. -#!+sb-propagate-fun-type +#-sb-xc-host ; (See CROSS-FLOAT-INFINITY-KLUDGE.) (progn (defun trig-derive-type-aux (arg domain fcn &optional def-lo def-hi (increasingp t)) @@ -1259,3 +1275,48 @@ #'cis)) ) ; PROGN + +;;;; TRUNCATE, FLOOR, CEILING, and ROUND + +(macrolet ((define-frobs (fun ufun) + `(progn + (defknown ,ufun (real) integer (movable foldable flushable)) + (deftransform ,fun ((x &optional by) + (* &optional + (constant-argument (member 1)))) + '(let ((res (,ufun x))) + (values res (- x res))))))) + (define-frobs truncate %unary-truncate) + (define-frobs round %unary-round)) + +;;; Convert (TRUNCATE x y) to the obvious implementation. We only want +;;; this when under certain conditions and let the generic TRUNCATE +;;; handle the rest. (Note: if Y = 1, the divide and multiply by Y +;;; should be removed by other DEFTRANSFORMs.) +(deftransform truncate ((x &optional y) + (float &optional (or float integer))) + (let ((defaulted-y (if y 'y 1))) + `(let ((res (%unary-truncate (/ x ,defaulted-y)))) + (values res (- x (* ,defaulted-y res)))))) + +(deftransform floor ((number &optional divisor) + (float &optional (or integer float))) + (let ((defaulted-divisor (if divisor 'divisor 1))) + `(multiple-value-bind (tru rem) (truncate number ,defaulted-divisor) + (if (and (not (zerop rem)) + (if (minusp ,defaulted-divisor) + (plusp number) + (minusp number))) + (values (1- tru) (+ rem ,defaulted-divisor)) + (values tru rem))))) + +(deftransform ceiling ((number &optional divisor) + (float &optional (or integer float))) + (let ((defaulted-divisor (if divisor 'divisor 1))) + `(multiple-value-bind (tru rem) (truncate number ,defaulted-divisor) + (if (and (not (zerop rem)) + (if (minusp ,defaulted-divisor) + (minusp number) + (plusp number))) + (values (1+ tru) (- rem ,defaulted-divisor)) + (values tru rem)))))