X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=base-target-features.lisp-expr;h=a116e33e1b7b0592680e0915061939ff2325d126;hb=959057baab99d4328fc386aee3fcc812f5fcb3ed;hp=3ae733fd123ecf61cec87327dee31888ce22ad90;hpb=b19093fa94d6e1785abee99c35c9a610e8777671;p=sbcl.git diff --git a/base-target-features.lisp-expr b/base-target-features.lisp-expr index 3ae733f..a116e33 100644 --- a/base-target-features.lisp-expr +++ b/base-target-features.lisp-expr @@ -3,9 +3,20 @@ ;;;; CL:*FEATURES* tags which have special meaning to SBCL or which ;;;; have a special conventional meaning ;;;; -;;;; Note that the preferred way to customize the features of a local -;;;; build of SBCL is not to edit this file, but to tweak -;;;; customize-target-features.lisp. +;;;; Note that the recommended way to customize the features of a +;;;; local build of SBCL is not to edit this file, but instead to +;;;; tweak customize-target-features.lisp. E.g. you can use code like +;;;; this: +;;;; (lambda (list) +;;;; (flet ((enable (x) (pushnew x list)) +;;;; (disable (x) (setf list (remove x list)))) +;;;; #+nil (enable :sb-show) +;;;; (enable :sb-after-xc-core) +;;;; #+nil (disable :sb-doc) +;;;; list)) +;;;; That way, because customize-target-features.lisp is in +;;;; .cvsignore, your local changes will remain local even if you use +;;;; "cvs diff" to submit patches to SBCL. ;;;; This software is part of the SBCL system. See the README file for ;;;; more information. @@ -29,7 +40,7 @@ :sbcl ;; Douglas Thomas Crosher's conservative generational GC (the only one - ;; we currently support) + ;; we currently support for X86) :gencgc ;; We're running under a UNIX. This is sort of redundant, and it was also @@ -53,59 +64,15 @@ ;; the executable I'm running. :sb-doc - ;; When this is set, EVAL is implemented as an "IR1 interpreter": - ;; code is compiled into the compiler's first internal representation, - ;; then the IR1 is interpreted. When this is not set, EVAL is implemented - ;; as a little bit of hackery wrapped around a call to COMPILE, i.e. - ;; the system becomes a "compiler-only implementation" of Common Lisp. - ;; As of sbcl-0.6.7, the compiler-only implementation is prototype code, - ;; and much less mature than the old IR1 interpreter. Thus, the safe - ;; thing is to leave :SB-INTERPRETER set. However, the compiler-only - ;; system is noticeably smaller, so you might want to omit - ;; :SB-INTERPRETER if you have a small machine. - ;; - ;; Probably, the compiler-only implementation will become more - ;; stable someday, and support for the IR1 interpreter will then be - ;; dropped. This will make the system smaller and easier to maintain - ;; not only because we no longer need to support the interpreter, - ;; but because code elsewhere in the system (the dumper, the debugger, - ;; etc.) no longer needs special cases for interpreted code. - :sb-interpreter - ;; Do regression and other tests when building the system. You ;; might or might not want this if you're not a developer, ;; depending on how paranoid you are. You probably do want it if ;; you are a developer. :sb-test - ;; :SB-PROPAGATE-FLOAT-TYPE and :SB-PROPAGATE-FUN-TYPE enable - ;; some numeric optimizer code in the target compiler. They - ;; correspond to the :PROPAGATE-FLOAT-TYPE and :PROPAGATE-FUN-TYPE - ;; features in the original CMU CL code, and while documentation - ;; existed for those, it seemed a little inconsistent. Despite the - ;; name, :SB-PROPAGATE-FLOAT-TYPE seems to control not only - ;; floating point optimizations, but some integer optimizations as - ;; well. - ;; - ;; CROSS-FLOAT-INFINITY-KLUDGE: - ;; * Even when these target features are enabled, the optimizations - ;; aren't enabled in the cross-compiler, because some of them - ;; depend on floating point infinities, which aren't in general - ;; supported on the cross-compilation host. - ;; * This is supported by hacking the features out of the - ;; *SHEBANG-FEATURES* list while we're building the cross-compiler. - ;; This is ugly and confusing and weird, but all the alternatives - ;; that I could think of seem messy and error-prone. That doesn't - ;; mean there's not a better way, though. Suggestions are welcome; - ;; or if you'd like to submit patches to make this code work - ;; without requiring floating point infinities, so that the entire - ;; problem goes away, that might be even better! -- WHN 2001-03-22 - :sb-propagate-float-type - :sb-propagate-fun-type - - ;; Setting this makes more debugging information available. - ;; If you aren't hacking or troubleshooting SBCL itself, you - ;; probably don't want this set. + ;; Make more debugging information available (for debugging SBCL + ;; itself). If you aren't hacking or troubleshooting SBCL itself, + ;; you probably don't want this set. ;; ;; At least two varieties of debugging information are enabled by this ;; option: @@ -128,6 +95,11 @@ ;; readtable configured so that the system sources can be read. ; :sb-show + ;; Build SBCL with the old CMU CL low level debugger, "ldb". If + ;; are aren't messing with CMU CL at a very low level (e.g. + ;; trying to diagnose GC problems) you shouldn't need this. + ; :sb-ldb + ;; This isn't really a target Lisp feature at all, but controls ;; whether the build process produces an after-xc.core file. This ;; can be useful for shortening the edit/compile/debug cycle if @@ -188,11 +160,6 @@ ;; affects a lot of floating point code. ; :negative-zero-is-not-zero - ;; It's unclear to me what this does (but it was enabled in the code - ;; that I picked up from Peter Van Eynde, called CONSTRAIN-FLOAT-TYPE - ;; instead of SB-CONSTRAIN-FLOAT-TYPE). -- WHN 19990224 - :sb-constrain-float-type - ;; This is set in classic CMU CL, and presumably there it means ;; that the floating point arithmetic implementation ;; conforms to IEEE's standard. Here it definitely means that the @@ -257,14 +224,18 @@ ;; really, really know what you're doing): ;; ;; machine architecture features: - ;; :x86 ; any Intel 386 or better, or compatibles like the AMD K6 or K7 - ;; (No others are supported by SBCL as of 0.6.7, but :alpha or - ;; :sparc support could be ported from CMU CL if anyone is - ;; sufficiently motivated to do so.) - ;; (CMU CL also had a :pentium feature, which affected the definition - ;; of some floating point vops. It was present but not enabled in the - ;; CMU CL code that SBCL is derived from, and is present but stale - ;; in SBCL as of 0.6.7.) + ;; :x86 + ;; any Intel 386 or better, or compatibles like the AMD K6 or K7 + ;; :alpha + ;; DEC/Compaq Alpha CPU + ;; (No other CPUs are supported by SBCL as of 0.6.12.15, but SPARC or + ;; PowerPC support could be ported from CMU CL if anyone is + ;; sufficiently motivated to do so, or if you're *really* motivated, + ;; you could write a port from scratch for a new CPU architecture.) + ;; (CMU CL also had a :pentium feature, which affected the definition + ;; of some floating point vops. It was present but not enabled or + ;; documented in the CMU CL code that SBCL is derived from, and is + ;; present but stale in SBCL as of 0.6.12.) ;; ;; operating system features: ;; :linux = We're intended to run under some version of Linux. @@ -275,5 +246,6 @@ ;; :openbsd = We're intended to run under FreeBSD. ;; (No others are supported by SBCL as of 0.6.7, but :hpux or ;; :solaris support could be ported from CMU CL if anyone is - ;; sufficiently motivated to do so.) + ;; sufficiently motivated to do so, and it'd even be possible, + ;; though harder, to port the system to Microsoft Windows.) )