The Q6600
Benchmarks Game

n-body Lisp SBCL #2 program

source code

;;   The Computer Language Benchmarks Game
;;   https://salsa.debian.org/benchmarksgame-team/benchmarksgame/
;;;
;;; contributed by Patrick Frankenberger
;;; modified by Juho Snellman 2005-11-18
;;;   * About 40% speedup on SBCL, 90% speedup on CMUCL
;;;   * Represent a body as a DEFSTRUCT with (:TYPE VECTOR DOUBLE-FLOAT), a
;;;     not as a structure that contains vectors
;;;   * Inline APPLYFORCES
;;;   * Replace (/ DT DISTANCE DISTANCE DISTANCE) with
;;;     (/ DT (* DISTANCE DISTANCE DISTANCE)), as is done in the other
;;;     implementations of this test.
;;;   * Add a couple of declarations
;;;   * Heavily rewritten for style (represent system as a list instead of
;;;     an array to make the nested iterations over it less clumsy, use
;;;     INCF/DECF where appropriate, break very long lines, etc)
;;; modified by Marko Kocic 
;;;   * add optimization declarations

(declaim (optimize (speed 3)(safety 0)(space 0)(debug 0)))

(defconstant +days-per-year+ 365.24d0)
(defconstant +solar-mass+ (* 4d0 pi pi))

(defstruct (body (:type (vector double-float))
                 (:conc-name nil)
                 (:constructor make-body (x y z vx vy vz mass)))
  x y z
  vx vy vz
  mass)
(deftype body () '(vector double-float 7))

(defparameter *jupiter*
  (make-body 4.84143144246472090d0
             -1.16032004402742839d0
             -1.03622044471123109d-1
             (* 1.66007664274403694d-3 +days-per-year+)
             (* 7.69901118419740425d-3 +days-per-year+)
             (* -6.90460016972063023d-5  +days-per-year+)
             (* 9.54791938424326609d-4 +solar-mass+)))

(defparameter *saturn*
  (make-body 8.34336671824457987d0
             4.12479856412430479d0
             -4.03523417114321381d-1
             (* -2.76742510726862411d-3 +days-per-year+)
             (* 4.99852801234917238d-3 +days-per-year+)
             (* 2.30417297573763929d-5 +days-per-year+)
             (* 2.85885980666130812d-4 +solar-mass+)))

(defparameter *uranus*
  (make-body 1.28943695621391310d1
             -1.51111514016986312d1
             -2.23307578892655734d-1
             (* 2.96460137564761618d-03 +days-per-year+)
             (* 2.37847173959480950d-03 +days-per-year+)
             (* -2.96589568540237556d-05 +days-per-year+)
             (* 4.36624404335156298d-05 +solar-mass+)))

(defparameter *neptune*
  (make-body 1.53796971148509165d+01
             -2.59193146099879641d+01
             1.79258772950371181d-01
             (* 2.68067772490389322d-03 +days-per-year+)
             (* 1.62824170038242295d-03 +days-per-year+)
             (* -9.51592254519715870d-05 +days-per-year+)
             (* 5.15138902046611451d-05 +solar-mass+)))

(defparameter *sun*
  (make-body 0.0d0 0.0d0 0.0d0 0.0d0 0.0d0 0.0d0 +solar-mass+))

(declaim (inline applyforces))
(defun applyforces (a b dt)
  (declare (type body a b) (type double-float dt))
  (let* ((dx (- (x a) (x b)))
         (dy (- (y a) (y b)))
         (dz (- (z a) (z b)))
	 (distance (sqrt (+ (* dx dx) (* dy dy) (* dz dz))))
	 (mag (/ dt (* distance distance distance)))
         (dxmag (* dx mag))
         (dymag (* dy mag))
         (dzmag (* dz mag)))
    (decf (vx a) (* dxmag (mass b)))
    (decf (vy a) (* dymag (mass b)))
    (decf (vz a) (* dzmag (mass b)))
    (incf (vx b) (* dxmag (mass a)))
    (incf (vy b) (* dymag (mass a)))
    (incf (vz b) (* dzmag (mass a))))
  nil)

(defun advance (system dt)
  (declare (double-float dt))
  (loop for (a . rest) on system do
        (dolist (b rest)
          (applyforces a b dt)))
  (dolist (b system)
    (incf (x b) (* dt (vx b)))
    (incf (y b) (* dt (vy b)))
    (incf (z b) (* dt (vz b))))
  nil)

(defun energy (system)
  (let ((e 0.0d0))
    (declare (double-float e))
    (loop for (a . rest) on system do
          (incf e (* 0.5d0
                     (mass a)
                     (+ (* (vx a) (vx a))
                        (* (vy a) (vy a))
                        (* (vz a) (vz a)))))
          (dolist (b rest)
            (let* ((dx (- (x a) (x b)))
                   (dy (- (y a) (y b)))
                   (dz (- (z a) (z b)))
                   (dist (sqrt (+ (* dx dx) (* dy dy) (* dz dz)))))
              (decf e (/ (* (mass a) (mass b)) dist)))))
    e))

(defun offset-momentum (system)
  (let ((px 0.0d0)
	(py 0.0d0)
	(pz 0.0d0))
    (dolist (p system)
      (incf px (* (vx p) (mass p)))
      (incf py (* (vy p) (mass p)))
      (incf pz (* (vz p) (mass p))))
    (setf (vx (car system)) (/ (- px) +solar-mass+)
          (vy (car system)) (/ (- py) +solar-mass+)
          (vz (car system)) (/ (- pz) +solar-mass+))
    nil))

(defun nbody (n)
  (declare (fixnum n))
  (let ((system (list *sun* *jupiter* *saturn* *uranus* *neptune*)))
    (offset-momentum system)
    (format t "~,9F~%" (energy system))
    (dotimes (i n)
      (advance system 0.01d0))
    (format t "~,9F~%" (energy system))))

(defun main ()
  (let ((n (parse-integer (or (car (last #+sbcl sb-ext:*posix-argv*
                                         #+cmu  extensions:*command-line-strings*
					 #+gcl  si::*command-args*)) "1"))))
    (nbody n)))
    

notes, command-line, and program output

NOTES:
64-bit Ubuntu quad core
SBCL 2.0.4


Fri, 22 May 2020 00:09:32 GMT

MAKE:
cp: 'nbody.sbcl-2.sbcl' and './nbody.sbcl-2.sbcl' are the same file
SBCL built with: /usr/local/bin/sbcl --userinit /dev/null --batch --eval '(load "nbody.sbcl-2.sbcl_compile")'
### START nbody.sbcl-2.sbcl_compile
(handler-bind ((sb-ext:defconstant-uneql      (lambda (c) (abort c))))      (require :sb-concurrency)      (load (compile-file "nbody.sbcl-2.sbcl" ))) (save-lisp-and-die "sbcl.core" :purify t)
### END nbody.sbcl-2.sbcl_compile

; compiling file "/home/dunham/8000-benchmarksgame/bench/nbody/nbody.sbcl-2.sbcl" (written 26 APR 2018 12:49:01 PM):
; compiling (DECLAIM (OPTIMIZE # ...))
; compiling (DEFCONSTANT +DAYS-PER-YEAR+ ...)
; compiling (DEFCONSTANT +SOLAR-MASS+ ...)
; compiling (DEFSTRUCT (BODY # ...) ...)
; file: /home/dunham/8000-benchmarksgame/bench/nbody/nbody.sbcl-2.sbcl
; in: DEFSTRUCT BODY
;     (DEFSTRUCT
;         (BODY (:TYPE (VECTOR DOUBLE-FLOAT)) (:CONC-NAME NIL)
;          (:CONSTRUCTOR MAKE-BODY (X Y Z VX VY VZ MASS)))
;       X
;       Y
;       Z
;       VX
;       VY
;       VZ
;       MASS)
; --> PROGN DEFUN PROGN SB-IMPL::%DEFUN SB-IMPL::%DEFUN SB-INT:NAMED-LAMBDA 
; ==>
;   #'(SB-INT:NAMED-LAMBDA X
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK X (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 0))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF X)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK X (SETF (ELT STRUCTURE 0) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA Y
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK Y (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 1))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF Y)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK Y (SETF (ELT STRUCTURE 1) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA Z
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK Z (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 2))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF Z)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK Z (SETF (ELT STRUCTURE 2) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA VX
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK VX (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 3))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF VX)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK VX (SETF (ELT STRUCTURE 3) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA VY
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK VY (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 4))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF VY)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK VY (SETF (ELT STRUCTURE 4) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA VZ
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK VZ (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 5))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF VZ)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK VZ (SETF (ELT STRUCTURE 5) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA MASS
;         (STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE))
;       (BLOCK MASS (THE (AND T DOUBLE-FLOAT) (ELT STRUCTURE 6))))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; ==>
;   #'(SB-INT:NAMED-LAMBDA (SETF MASS)
;         (SB-KERNEL::VALUE STRUCTURE)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (DECLARE (TYPE (SIMPLE-ARRAY DOUBLE-FLOAT (*)) STRUCTURE)
;                (TYPE (AND T DOUBLE-FLOAT) SB-KERNEL::VALUE))
;       (BLOCK MASS (SETF (ELT STRUCTURE 6) SB-KERNEL::VALUE)))
; 
; note: doing float to pointer coercion (cost 13) to "<return value>"

; compiling (DEFTYPE BODY ...)
; compiling (DEFPARAMETER *JUPITER* ...)
; compiling (DEFPARAMETER *SATURN* ...)
; compiling (DEFPARAMETER *URANUS* ...)
; compiling (DEFPARAMETER *NEPTUNE* ...)
; compiling (DEFPARAMETER *SUN* ...)
; compiling (DECLAIM (INLINE APPLYFORCES))
; compiling (DEFUN APPLYFORCES ...)
; compiling (DEFUN ADVANCE ...)
; compiling (DEFUN ENERGY ...)
; file: /home/dunham/8000-benchmarksgame/bench/nbody/nbody.sbcl-2.sbcl
; in: DEFUN ENERGY
;     (DEFUN ENERGY (SYSTEM)
;       (LET ((E 0.0d0))
;         (DECLARE (DOUBLE-FLOAT E))
;         (LOOP FOR (A . REST) ON SYSTEM
;               DO (INCF E (* 0.5d0 # #)) (DOLIST (B REST)
;                                           (LET* #
;                                             #)))
;         E))
; --> PROGN SB-IMPL::%DEFUN SB-IMPL::%DEFUN SB-INT:NAMED-LAMBDA 
; ==>
;   #'(SB-INT:NAMED-LAMBDA ENERGY
;         (SYSTEM)
;       (DECLARE (SB-C::TOP-LEVEL-FORM))
;       (BLOCK ENERGY
;         (LET ((E 0.0d0))
;           (DECLARE (DOUBLE-FLOAT E))
;           (LOOP FOR (A . REST) ON SYSTEM
;                 DO (INCF E #) (DOLIST # #))
;           E)))
; 
; note: doing float to pointer coercion (cost 13) from E to "<return value>"

; compiling (DEFUN OFFSET-MOMENTUM ...)
; file: /home/dunham/8000-benchmarksgame/bench/nbody/nbody.sbcl-2.sbcl
; in: DEFUN OFFSET-MOMENTUM
;     (- PX)
; ==>
;   (SB-KERNEL:%NEGATE (THE NUMBER PX))
; 
; note: unable to
;   Eliminate %negate/%negate of rationals
; due to type uncertainty:
;   The first argument is a NUMBER, not a RATIONAL.

;     (/ (- PX) +SOLAR-MASS+)
; 
; note: unable to
;   convert to multiplication by reciprocal
; due to type uncertainty:
;   The first argument is a NUMBER, not a DOUBLE-FLOAT.

;     (- PY)
; ==>
;   (SB-KERNEL:%NEGATE (THE NUMBER PY))
; 
; note: unable to
;   Eliminate %negate/%negate of rationals
; due to type uncertainty:
;   The first argument is a NUMBER, not a RATIONAL.

;     (/ (- PY) +SOLAR-MASS+)
; 
; note: unable to
;   convert to multiplication by reciprocal
; due to type uncertainty:
;   The first argument is a NUMBER, not a DOUBLE-FLOAT.

;     (- PZ)
; ==>
;   (SB-KERNEL:%NEGATE (THE NUMBER PZ))
; 
; note: unable to
;   Eliminate %negate/%negate of rationals
; due to type uncertainty:
;   The first argument is a NUMBER, not a RATIONAL.

;     (/ (- PZ) +SOLAR-MASS+)
; 
; note: unable to
;   convert to multiplication by reciprocal
; due to type uncertainty:
;   The first argument is a NUMBER, not a DOUBLE-FLOAT.

;     (INCF PX (* (VX P) (MASS P)))
; --> SETQ THE 
; ==>
;   (+ (* (VX P) (MASS P)) PX)
; 
; note: forced to do GENERIC-+ (cost 10)
;       unable to do inline float arithmetic (cost 2) because:
;       The second argument is a NUMBER, not a DOUBLE-FLOAT.
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES DOUBLE-FLOAT
;                                                                &REST T).
;       unable to do inline float arithmetic (cost 4) because:
;       The second argument is a NUMBER, not a (COMPLEX DOUBLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX DOUBLE-FLOAT)
;                                                         &REST T).

;     (INCF PY (* (VY P) (MASS P)))
; --> SETQ THE 
; ==>
;   (+ (* (VY P) (MASS P)) PY)
; 
; note: forced to do GENERIC-+ (cost 10)
;       unable to do inline float arithmetic (cost 2) because:
;       The second argument is a NUMBER, not a DOUBLE-FLOAT.
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES DOUBLE-FLOAT
;                                                                &REST T).
;       unable to do inline float arithmetic (cost 4) because:
;       The second argument is a NUMBER, not a (COMPLEX DOUBLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX DOUBLE-FLOAT)
;                                                         &REST T).

;     (INCF PZ (* (VZ P) (MASS P)))
; --> SETQ THE 
; ==>
;   (+ (* (VZ P) (MASS P)) PZ)
; 
; note: forced to do GENERIC-+ (cost 10)
;       unable to do inline float arithmetic (cost 2) because:
;       The second argument is a NUMBER, not a DOUBLE-FLOAT.
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES DOUBLE-FLOAT
;                                                                &REST T).
;       unable to do inline float arithmetic (cost 4) because:
;       The second argument is a NUMBER, not a (COMPLEX DOUBLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX DOUBLE-FLOAT)
;                                                         &REST T).

;     (- PX)
; ==>
;   (SB-KERNEL:%NEGATE (THE NUMBER PX))
; 
; note: forced to do GENERIC-NEGATE (cost 10)
;       unable to do inline float arithmetic (cost 1) because:
;       The first argument is a NUMBER, not a (COMPLEX SINGLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX SINGLE-FLOAT)
;                                                         &REST T).
;       unable to do inline float arithmetic (cost 1) because:
;       The first argument is a NUMBER, not a (COMPLEX DOUBLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX DOUBLE-FLOAT)
;                                                         &REST T).
;       etc.

;     (/ (- PX) +SOLAR-MASS+)
; 
; note: forced to do full call
;       unable to do inline float arithmetic (cost 19) because:
;       The first argument is a NUMBER, not a DOUBLE-FLOAT.

;     (- PY)
; ==>
;   (SB-KERNEL:%NEGATE (THE NUMBER PY))
; 
; note: forced to do GENERIC-NEGATE (cost 10)
;       unable to do inline float arithmetic (cost 1) because:
;       The first argument is a NUMBER, not a (COMPLEX SINGLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX SINGLE-FLOAT)
;                                                         &REST T).
;       unable to do inline float arithmetic (cost 1) because:
;       The first argument is a NUMBER, not a (COMPLEX DOUBLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX DOUBLE-FLOAT)
;                                                         &REST T).
;       etc.

;     (/ (- PY) +SOLAR-MASS+)
; 
; note: forced to do full call
;       unable to do inline float arithmetic (cost 19) because:
;       The first argument is a NUMBER, not a DOUBLE-FLOAT.

;     (- PZ)
; ==>
;   (SB-KERNEL:%NEGATE (THE NUMBER PZ))
; 
; note: forced to do GENERIC-NEGATE (cost 10)
;       unable to do inline float arithmetic (cost 1) because:
;       The first argument is a NUMBER, not a (COMPLEX SINGLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX SINGLE-FLOAT)
;                                                         &REST T).
;       unable to do inline float arithmetic (cost 1) because:
;       The first argument is a NUMBER, not a (COMPLEX DOUBLE-FLOAT).
;       The result is a (VALUES NUMBER &OPTIONAL), not a (VALUES
;                                                         (COMPLEX DOUBLE-FLOAT)
;                                                         &REST T).
;       etc.

;     (/ (- PZ) +SOLAR-MASS+)
; 
; note: forced to do full call
;       unable to do inline float arithmetic (cost 19) because:
;       The first argument is a NUMBER, not a DOUBLE-FLOAT.

;     (INCF PX (* (VX P) (MASS P)))
; --> SETQ THE 
; ==>
;   (+ (* (VX P) (MASS P)) PX)
; 
; note: doing float to pointer coercion (cost 13), for:
;       the first argument of GENERIC-+

;     (INCF PY (* (VY P) (MASS P)))
; --> SETQ THE 
; ==>
;   (+ (* (VY P) (MASS P)) PY)
; 
; note: doing float to pointer coercion (cost 13), for:
;       the first argument of GENERIC-+

;     (INCF PZ (* (VZ P) (MASS P)))
; --> SETQ THE 
; ==>
;   (+ (* (VZ P) (MASS P)) PZ)
; 
; note: doing float to pointer coercion (cost 13), for:
;       the first argument of GENERIC-+

; compiling (DEFUN NBODY ...)
; compiling (DEFUN MAIN ...); 
; compilation unit finished
;   printed 33 notes


; wrote /home/dunham/benchmarksgame_quadcore/nbody/tmp/nbody.sbcl-2.fasl
; compilation finished in 0:00:00.249
### START nbody.sbcl-2.sbcl_run
(main) (quit)
### END nbody.sbcl-2.sbcl_run


4.82s to complete and log all make actions

COMMAND LINE:
/usr/local/bin/sbcl --dynamic-space-size 500 --noinform --core sbcl.core --userinit /dev/null --load nbody.sbcl-2.sbcl_run 50000000

PROGRAM OUTPUT:
-0.169075164
-0.169059907