(in-package "SB!VM")
-(file-comment
- "$Header$")
-
(eval-when (:compile-toplevel :load-toplevel :execute)
-(defconstant float-trap-alist
+(defparameter *float-trap-alist*
(list (cons :underflow float-underflow-trap-bit)
- (cons :overflow float-overflow-trap-bit)
- (cons :inexact float-inexact-trap-bit)
- (cons :invalid float-invalid-trap-bit)
- (cons :divide-by-zero float-divide-by-zero-trap-bit)
- #!+x86 (cons :denormalized-operand float-denormal-trap-bit)))
-
-;;; Return a mask with all the specified float trap bits set.
-(defun float-trap-mask (names)
- (reduce #'logior
- (mapcar #'(lambda (x)
- (or (cdr (assoc x float-trap-alist))
- (error "Unknown float trap kind: ~S." x)))
- names)))
+ (cons :overflow float-overflow-trap-bit)
+ (cons :inexact float-inexact-trap-bit)
+ (cons :invalid float-invalid-trap-bit)
+ (cons :divide-by-zero float-divide-by-zero-trap-bit)
+ #!+x86 (cons :denormalized-operand float-denormal-trap-bit)))
-(defconstant rounding-mode-alist
+(defparameter *rounding-mode-alist*
(list (cons :nearest float-round-to-nearest)
- (cons :zero float-round-to-zero)
- (cons :positive-infinity float-round-to-positive)
- (cons :negative-infinity float-round-to-negative)))
-
-); Eval-When (Compile Load Eval)
+ (cons :zero float-round-to-zero)
+ (cons :positive-infinity float-round-to-positive)
+ (cons :negative-infinity float-round-to-negative)))
-;;; interpreter stubs
-(defun floating-point-modes () (floating-point-modes))
-(defun (setf floating-point-modes) (new) (setf (floating-point-modes) new))
+#!+x86
+(defparameter *precision-mode-alist*
+ (list (cons :24-bit float-precision-24-bit)
+ (cons :53-bit float-precision-53-bit)
+ (cons :64-bit float-precision-64-bit)))
-(defun set-floating-point-modes (&key (traps nil traps-p)
- (rounding-mode nil round-p)
- (current-exceptions nil current-x-p)
- (accrued-exceptions nil accrued-x-p)
- (fast-mode nil fast-mode-p))
+;;; Return a mask with all the specified float trap bits set.
+(defun float-trap-mask (names)
+ (reduce #'logior
+ (mapcar (lambda (x)
+ (or (cdr (assoc x *float-trap-alist*))
+ (error "unknown float trap kind: ~S" x)))
+ names)))
+) ; EVAL-WHEN
+
+;;; interpreter stubs for floating point modes get/setters for the
+;;; alpha have been removed to alpha-vm.lisp, as they are implemented
+;;; in C rather than as VOPs. Likewise for x86-64 and mips.
+#!-(or alpha x86-64 mips)
+(progn
+ (defun floating-point-modes ()
+ (floating-point-modes))
+ (defun (setf floating-point-modes) (new)
+ (setf (floating-point-modes) new)))
+
+(defun set-floating-point-modes (&key
+ (traps nil traps-p)
+ (rounding-mode nil round-p)
+ (current-exceptions nil current-x-p)
+ (accrued-exceptions nil accrued-x-p)
+ (fast-mode nil fast-mode-p)
+ #!+x86 (precision nil precisionp))
#!+sb-doc
- "This function sets options controlling the floating-point hardware. If a
- keyword is not supplied, then the current value is preserved. Possible
- keywords:
-
- :TRAPS
- A list of the exception conditions that should cause traps. Possible
- exceptions are :UNDERFLOW, :OVERFLOW, :INEXACT, :INVALID,
- :DIVIDE-BY-ZERO, and on the X86 :DENORMALIZED-OPERAND. Initially
- all traps except :INEXACT are enabled.
-
- :ROUNDING-MODE
- The rounding mode to use when the result is not exact. Possible values
- are :NEAREST, :POSITIVE-INFINITY, :NEGATIVE-INFINITY and :ZERO.
- Initially, the rounding mode is :NEAREST.
-
- :CURRENT-EXCEPTIONS
- :ACCRUED-EXCEPTIONS
- These arguments allow setting of the exception flags. The main use is
- setting the accrued exceptions to NIL to clear them.
-
- :FAST-MODE
- Set the hardware's \"fast mode\" flag, if any. When set, IEEE
- conformance or debuggability may be impaired. Some machines may not
- have this feature, in which case the value is always NIL.
-
- GET-FLOATING-POINT-MODES may be used to find the floating point modes
- currently in effect."
+ "This function sets options controlling the floating-point
+hardware. If a keyword is not supplied, then the current value is
+preserved. Possible keywords:
+
+ :TRAPS
+ A list of the exception conditions that should cause traps.
+ Possible exceptions are :UNDERFLOW, :OVERFLOW, :INEXACT, :INVALID,
+ :DIVIDE-BY-ZERO, and on the X86 :DENORMALIZED-OPERAND.
+
+:ROUNDING-MODE
+ The rounding mode to use when the result is not exact. Possible
+ values are :NEAREST, :POSITIVE-INFINITY, :NEGATIVE-INFINITY and
+ :ZERO. Setting this away from :NEAREST is liable to upset SBCL's
+ maths routines which depend on it.
+
+:CURRENT-EXCEPTIONS
+:ACCRUED-EXCEPTIONS
+ These arguments allow setting of the exception flags. The main
+ use is setting the accrued exceptions to NIL to clear them.
+
+:FAST-MODE
+ Set the hardware's \"fast mode\" flag, if any. When set, IEEE
+ conformance or debuggability may be impaired. Some machines don't
+ have this feature, and some SBCL ports don't implement it anyway
+ -- in such cases the value is always NIL.
+
+:PRECISION (x86 only)
+ :24-bit, :53-bit and :64-bit, for the internal precision of the mantissa.
+
+GET-FLOATING-POINT-MODES may be used to find the floating point modes
+currently in effect. SAVE-LISP-AND-DIE preserves the floating point modes
+in effect."
(let ((modes (floating-point-modes)))
(when traps-p
(setf (ldb float-traps-byte modes) (float-trap-mask traps)))
(when round-p
(setf (ldb float-rounding-mode modes)
- (or (cdr (assoc rounding-mode rounding-mode-alist))
- (error "Unknown rounding mode: ~S." rounding-mode))))
+ (or (cdr (assoc rounding-mode *rounding-mode-alist*))
+ (error "unknown rounding mode: ~S" rounding-mode))))
(when current-x-p
(setf (ldb float-exceptions-byte modes)
- (float-trap-mask current-exceptions)))
+ (float-trap-mask current-exceptions)))
(when accrued-x-p
(setf (ldb float-sticky-bits modes)
- (float-trap-mask accrued-exceptions)))
+ (float-trap-mask accrued-exceptions)))
(when fast-mode-p
(if fast-mode
- (setq modes (logior float-fast-bit modes))
- (setq modes (logand (lognot float-fast-bit) modes))))
+ (setq modes (logior float-fast-bit modes))
+ (setq modes (logand (lognot float-fast-bit) modes))))
+ #!+x86
+ (when precisionp
+ (setf (ldb float-precision-control modes)
+ (or (cdr (assoc precision *precision-mode-alist*))
+ (error "unknown precision mode: ~S" precision))))
+ ;; FIXME: This apparently doesn't work on Darwin
+ #!-(and darwin ppc)
(setf (floating-point-modes) modes))
-
(values))
(defun get-floating-point-modes ()
#!+sb-doc
- "This function returns a list representing the state of the floating point
- modes. The list is in the same format as the keyword arguments to
- SET-FLOATING-POINT-MODES, i.e.
- (apply #'set-floating-point-modes (get-floating-point-modes))
+ "This function returns a list representing the state of the floating
+point modes. The list is in the same format as the &KEY arguments to
+SET-FLOATING-POINT-MODES, i.e.
- sets the floating point modes to their current values (and thus is a no-op)."
+ (apply #'set-floating-point-modes (get-floating-point-modes))
+
+sets the floating point modes to their current values (and thus is a no-op)."
(flet ((exc-keys (bits)
- (macrolet ((frob ()
- `(collect ((res))
- ,@(mapcar #'(lambda (x)
- `(when (logtest bits ,(cdr x))
- (res ',(car x))))
- float-trap-alist)
- (res))))
- (frob))))
+ (macrolet ((frob ()
+ `(collect ((res))
+ ,@(mapcar (lambda (x)
+ `(when (logtest bits ,(cdr x))
+ (res ',(car x))))
+ *float-trap-alist*)
+ (res))))
+ (frob))))
(let ((modes (floating-point-modes)))
`(:traps ,(exc-keys (ldb float-traps-byte modes))
- :rounding-mode ,(car (rassoc (ldb float-rounding-mode modes)
- rounding-mode-alist))
- :current-exceptions ,(exc-keys (ldb float-exceptions-byte modes))
- :accrued-exceptions ,(exc-keys (ldb float-sticky-bits modes))
- :fast-mode ,(logtest float-fast-bit modes)))))
-
+ :rounding-mode ,(car (rassoc (ldb float-rounding-mode modes)
+ *rounding-mode-alist*))
+ :current-exceptions ,(exc-keys (ldb float-exceptions-byte modes))
+ :accrued-exceptions ,(exc-keys (ldb float-sticky-bits modes))
+ :fast-mode ,(logtest float-fast-bit modes)
+ #!+x86 :precision
+ #!+x86 ,(car (rassoc (ldb float-precision-control modes)
+ *precision-mode-alist*))))))
+
+;;; FIXME: For some unknown reason, NetBSD/x86 won't run with the
+;;; :INVALID trap enabled. That should be fixed, but not today...
+;;;
+;;; PRINT seems not to like x86 NPX denormal floats like
+;;; LEAST-NEGATIVE-SINGLE-FLOAT, so the :UNDERFLOW exceptions are
+;;; disabled by default. Joe User can explicitly enable them if
+;;; desired.
+(defvar *saved-floating-point-modes*
+ '(:traps (:overflow #!-(or netbsd ppc) :invalid :divide-by-zero)
+ :rounding-mode :nearest :current-exceptions nil
+ :accrued-exceptions nil :fast-mode nil
+ #!+x86 :precision #!+x86 :53-bit))
+
+(defun float-cold-init-or-reinit ()
+ (apply #'set-floating-point-modes *saved-floating-point-modes*))
+
+(defun float-deinit ()
+ (setf *saved-floating-point-modes* (get-floating-point-modes)))
+
+;;; Return true if any of the named traps are currently trapped, false
+;;; otherwise.
(defmacro current-float-trap (&rest traps)
- #!+sb-doc
- "Current-Float-Trap Trap-Name*
- Return true if any of the named traps are currently trapped, false
- otherwise."
`(not (zerop (logand ,(dpb (float-trap-mask traps) float-traps-byte 0)
- (floating-point-modes)))))
+ (floating-point-modes)))))
+
+;;; SIGFPE code to floating-point error
+#!-win32
+(defparameter *sigfpe-code-error-alist*
+ (list (cons sb!unix::fpe-intovf 'floating-point-overflow)
+ (cons sb!unix::fpe-intdiv 'division-by-zero)
+ (cons sb!unix::fpe-fltdiv 'division-by-zero)
+ (cons sb!unix::fpe-fltovf 'floating-point-overflow)
+ (cons sb!unix::fpe-fltund 'floating-point-underflow)
+ (cons sb!unix::fpe-fltres 'floating-point-inexact)
+ (cons sb!unix::fpe-fltinv 'floating-point-invalid-operation)
+ (cons sb!unix::fpe-fltsub 'floating-point-exception)))
;;; Signal the appropriate condition when we get a floating-point error.
+#!-win32
(defun sigfpe-handler (signal info context)
- (declare (ignore signal info))
- (declare (type system-area-pointer context))
- ;; FIXME: The find-the-detailed-problem code below went stale with
- ;; the big switchover to POSIX signal handling and signal contexts
- ;; which are opaque at the Lisp level ca plod-0.6.7. It needs to be
- ;; revived, which will require writing a C-level os-dependent
- ;; function to extract floating point modes, and a Lisp-level
- ;; DEF-ALIEN-ROUTINE to get to the C-level os-dependent function.
- ;; Meanwhile we just say "something went wrong".
- (error 'floating-point-exception)
- #|
- (let* ((modes (context-floating-point-modes
- (sb!alien:sap-alien context (* os-context-t))))
- (traps (logand (ldb float-exceptions-byte modes)
- (ldb float-traps-byte modes))))
- (cond ((not (zerop (logand float-divide-by-zero-trap-bit traps)))
- (error 'division-by-zero))
- ((not (zerop (logand float-invalid-trap-bit traps)))
- (error 'floating-point-invalid-operation))
- ((not (zerop (logand float-overflow-trap-bit traps)))
- (error 'floating-point-overflow))
- ((not (zerop (logand float-underflow-trap-bit traps)))
- (error 'floating-point-underflow))
- ((not (zerop (logand float-inexact-trap-bit traps)))
- (error 'floating-point-inexact))
- #!+FreeBSD
- ((zerop (ldb float-exceptions-byte modes))
- ;; I can't tell what caused the exception!!
- (error 'floating-point-exception
- :traps (getf (get-floating-point-modes) :traps)))
- (t
- (error "SIGFPE with no exceptions currently enabled?"))))
- |#
- )
-
+ (declare (ignore signal context))
+ (declare (type system-area-pointer info))
+ (let ((code (sb!unix::siginfo-code info)))
+ (with-interrupts
+ ;; Reset the accumulated exceptions, may be needed on other
+ ;; platforms too, at least Linux doesn't seem to require it.
+ #!+sunos
+ (setf (ldb sb!vm::float-sticky-bits (floating-point-modes)) 0)
+ (error (or (cdr (assoc code *sigfpe-code-error-alist*))
+ 'floating-point-exception)))))
+
+;;; Execute BODY with the floating point exceptions listed in TRAPS
+;;; masked (disabled). TRAPS should be a list of possible exceptions
+;;; which includes :UNDERFLOW, :OVERFLOW, :INEXACT, :INVALID and
+;;; :DIVIDE-BY-ZERO and on the X86 :DENORMALIZED-OPERAND. The
+;;; respective accrued exceptions are cleared at the start of the body
+;;; to support their testing within, and restored on exit.
(defmacro with-float-traps-masked (traps &body body)
- #!+sb-doc
- "Execute BODY with the floating point exceptions listed in TRAPS
- masked (disabled). TRAPS should be a list of possible exceptions
- which includes :UNDERFLOW, :OVERFLOW, :INEXACT, :INVALID and
- :DIVIDE-BY-ZERO and on the X86 :DENORMALIZED-OPERAND. The respective
- accrued exceptions are cleared at the start of the body to support
- their testing within, and restored on exit."
(let ((traps (dpb (float-trap-mask traps) float-traps-byte 0))
- (exceptions (dpb (float-trap-mask traps) float-sticky-bits 0))
- (trap-mask (dpb (lognot (float-trap-mask traps))
- float-traps-byte #xffffffff))
- (exception-mask (dpb (lognot (sb!vm::float-trap-mask traps))
- float-sticky-bits #xffffffff)))
- `(let ((orig-modes (floating-point-modes)))
+ (exceptions (dpb (float-trap-mask traps) float-sticky-bits 0))
+ (trap-mask (dpb (lognot (float-trap-mask traps))
+ float-traps-byte #xffffffff))
+ (exception-mask (dpb (lognot (float-trap-mask traps))
+ float-sticky-bits #xffffffff))
+ (orig-modes (gensym)))
+ `(let ((,orig-modes (floating-point-modes)))
(unwind-protect
- (progn
- (setf (floating-point-modes)
- (logand orig-modes ,(logand trap-mask exception-mask)))
- ,@body)
- ;; Restore the original traps and exceptions.
- (setf (floating-point-modes)
- (logior (logand orig-modes ,(logior traps exceptions))
- (logand (floating-point-modes)
- ,(logand trap-mask exception-mask))))))))
+ (progn
+ (setf (floating-point-modes)
+ (logand ,orig-modes ,(logand trap-mask exception-mask)))
+ ,@body)
+ ;; Restore the original traps and exceptions.
+ (setf (floating-point-modes)
+ (logior (logand ,orig-modes ,(logior traps exceptions))
+ (logand (floating-point-modes)
+ ,(logand trap-mask exception-mask))))))))