6fcc9fa8e6
A direct (+ 1.5M 2.5M) emits a raw Chez + that rejects the bigdec record. Rather than guard every arithmetic call site (measured 2-4x on unhinted fixnum loops), let the analyzer dispatch where it can prove the type. jolt.passes.numeric seeds a :bigdec kind from the M-literal and flows it through let/loop/if like the existing :double/:long kinds; an arithmetic/comparison invoke whose operands are all bigdec (integer literals allowed) gets :num-kind :bigdec. The back end (bd-ops + emit-numeric) lowers those to the bigdec.ss engine (jbd-add/-sub/-mul/-div, jbd-lt?/…, jbd-zero?/-pos?/-neg?, jbd-quot/-rem). Zero cost on non-bigdec code: with no bigdec literals present the kind never arises, so emission is byte-identical — the re-mint leaves prelude.ss unchanged, only image.ss (the compiler) moves. Gaps (filed): a bigdec mixed with a flonum in call position, and a bigdec the analyzer types :any, still hit the raw op and throw; use value position or a literal-typed let. Re-mint (numeric/backend are seed sources). 16 JVM-certified corpus rows.
231 lines
12 KiB
Scheme
231 lines
12 KiB
Scheme
;; BigDecimal. A jbigdec is {unscaled, scale} over Chez arbitrary-precision exact
|
|
;; integers; its value is unscaled * 10^-scale (1.5M = {15,1}, 1.00M = {100,2},
|
|
;; 3M = {3,0}). M-suffix literals read to a :bigdec form that the back end lowers
|
|
;; to jolt-bigdec-from-string; bigdec coerces a number/string. Equality is by
|
|
;; value (1.0M = 1.00M), str drops the M, pr keeps it, class is
|
|
;; java.math.BigDecimal.
|
|
;;
|
|
;; Arithmetic follows java.math.BigDecimal's scale rules: add/sub align to the
|
|
;; larger scale; multiply adds scales; divide gives the exact quotient at minimal
|
|
;; scale or throws ArithmeticException on a non-terminating expansion. Clojure
|
|
;; contagion: a bigdec mixed with an integer stays a bigdec; a flonum operand wins
|
|
;; (the result is a double). jbd-add/-sub/-mul/-div, the jbd-lt?/…/zero? helpers,
|
|
;; and jbd-quot/-rem are the shared engine. Two paths reach it, both leaving the
|
|
;; inlined native hot path untouched:
|
|
;; - value position ((reduce + bigs)/(apply * bigs)): the jolt-add/-sub/-mul/-div
|
|
;; and compare shims dispatch here when a bigdec operand is present.
|
|
;; - call position ((+ 1.5M 2.5M), (< a b), (zero? b)): jolt.passes.numeric tags
|
|
;; the invoke :num-kind :bigdec when every operand is statically a bigdec (M
|
|
;; literal or a let-bound copy, integer literals allowed), and the back end
|
|
;; lowers it to the jbd op. Non-bigdec code is unaffected.
|
|
;; Gaps (a runtime bigdec the analyzer can't see statically): a bigdec mixed with a
|
|
;; flonum in call position ((+ 1.5M 2.0)) and arithmetic over a bigdec the analyzer
|
|
;; types as :any ((+ (bigdec x) 1)) fall through to the raw op and throw; use value
|
|
;; position or a literal-typed let.
|
|
|
|
(define-record-type jbigdec (fields unscaled scale) (nongenerative chez-jbigdec-v1))
|
|
|
|
(define (bd-index-char s ch)
|
|
(let loop ((i 0))
|
|
(cond ((>= i (string-length s)) #f)
|
|
((char=? (string-ref s i) ch) i)
|
|
(else (loop (+ i 1))))))
|
|
|
|
;; "1.50" -> {150,2}; "3" -> {3,0}; "-0.0" -> {0,1}; ".5" -> {5,1}.
|
|
(define (jolt-bigdec-from-string s)
|
|
(let* ((neg (and (> (string-length s) 0) (char=? (string-ref s 0) #\-)))
|
|
(sgn (and (> (string-length s) 0) (or neg (char=? (string-ref s 0) #\+))))
|
|
(s1 (if sgn (substring s 1 (string-length s)) s))
|
|
(sign (if neg -1 1))
|
|
(dot (bd-index-char s1 #\.)))
|
|
(if dot
|
|
(let* ((intp (substring s1 0 dot))
|
|
(fracp (substring s1 (+ dot 1) (string-length s1)))
|
|
(digs (string-append intp fracp))
|
|
(unscaled (if (= 0 (string-length digs)) 0 (string->number digs))))
|
|
(make-jbigdec (* sign unscaled) (string-length fracp)))
|
|
(make-jbigdec (* sign (string->number s1)) 0))))
|
|
|
|
;; bigdec coercion: a bigdec is itself; an exact integer keeps scale 0; a string
|
|
;; or any other number routes through its decimal text.
|
|
(define (jolt-bigdec x)
|
|
(cond
|
|
((jbigdec? x) x)
|
|
((and (number? x) (exact? x) (integer? x)) (make-jbigdec x 0))
|
|
((string? x) (jolt-bigdec-from-string x))
|
|
((number? x) (jolt-bigdec-from-string (jolt-num->string x)))
|
|
(else (error #f "bigdec: cannot coerce" x))))
|
|
|
|
;; value equality: unscaled_a * 10^scale_b == unscaled_b * 10^scale_a.
|
|
(define (jbigdec=? a b)
|
|
(= (* (jbigdec-unscaled a) (expt 10 (jbigdec-scale b)))
|
|
(* (jbigdec-unscaled b) (expt 10 (jbigdec-scale a)))))
|
|
|
|
;; render the decimal text (no M): insert the point `scale` digits from the right.
|
|
(define (jbigdec->string bd)
|
|
(let* ((u (jbigdec-unscaled bd)) (sc (jbigdec-scale bd))
|
|
(neg (< u 0)) (digs (number->string (abs u))))
|
|
(string-append
|
|
(if neg "-" "")
|
|
(if (<= sc 0)
|
|
digs
|
|
(let* ((padded (if (<= (string-length digs) sc)
|
|
(string-append (make-string (- (+ sc 1) (string-length digs)) #\0) digs)
|
|
digs))
|
|
(pl (string-length padded)))
|
|
(string-append (substring padded 0 (- pl sc)) "." (substring padded (- pl sc) pl)))))))
|
|
|
|
;; value as a Chez flonum (for double contagion: a flonum operand wins).
|
|
(define (jbigdec->flonum b)
|
|
(exact->inexact (/ (jbigdec-unscaled b) (expt 10 (jbigdec-scale b)))))
|
|
|
|
;; coerce an exact integer to a scale-0 bigdec; pass a bigdec through. Used on the
|
|
;; non-flonum mixed path (bigdec + long -> bigdec).
|
|
(define (jbd-coerce x)
|
|
(cond ((jbigdec? x) x)
|
|
((and (number? x) (exact? x) (integer? x)) (make-jbigdec x 0))
|
|
(else (error #f "bigdec arithmetic: cannot coerce operand" x))))
|
|
|
|
;; --- core arithmetic on the {unscaled, scale} pair --------------------------
|
|
;; align two bigdecs to a common scale, returning (unscaled-a unscaled-b scale).
|
|
(define (jbd-align a b)
|
|
(let ((sa (jbigdec-scale a)) (sb (jbigdec-scale b)))
|
|
(cond
|
|
((= sa sb) (values (jbigdec-unscaled a) (jbigdec-unscaled b) sa))
|
|
((> sa sb) (values (jbigdec-unscaled a)
|
|
(* (jbigdec-unscaled b) (expt 10 (- sa sb))) sa))
|
|
(else (values (* (jbigdec-unscaled a) (expt 10 (- sb sa)))
|
|
(jbigdec-unscaled b) sb)))))
|
|
|
|
(define (jbd2+ a b) (let-values (((ua ub s) (jbd-align a b))) (make-jbigdec (+ ua ub) s)))
|
|
(define (jbd2- a b) (let-values (((ua ub s) (jbd-align a b))) (make-jbigdec (- ua ub) s)))
|
|
(define (jbd2* a b) (make-jbigdec (* (jbigdec-unscaled a) (jbigdec-unscaled b))
|
|
(+ (jbigdec-scale a) (jbigdec-scale b))))
|
|
(define (jbd-negate a) (make-jbigdec (- (jbigdec-unscaled a)) (jbigdec-scale a)))
|
|
|
|
;; exact rational -> bigdec at minimal scale, or throw if non-terminating. den must
|
|
;; factor into 2s and 5s; scale = max(count2, count5).
|
|
(define (jbd-rational->bigdec r)
|
|
(let ((p (numerator r)) (q (denominator r)))
|
|
(let loop ((d q) (c2 0) (c5 0))
|
|
(cond
|
|
((= d 1) (let ((sc (max c2 c5)))
|
|
(make-jbigdec (* p (quotient (expt 10 sc) q)) sc)))
|
|
((= 0 (modulo d 2)) (loop (quotient d 2) (+ c2 1) c5))
|
|
((= 0 (modulo d 5)) (loop (quotient d 5) c2 (+ c5 1)))
|
|
(else (jolt-throw (jolt-host-throwable
|
|
"java.lang.ArithmeticException"
|
|
"Non-terminating decimal expansion; no exact representable decimal result.")))))))
|
|
|
|
(define (jbd2-div a b)
|
|
(when (= 0 (jbigdec-unscaled b))
|
|
(jolt-throw (jolt-host-throwable "java.lang.ArithmeticException" "Divide by zero")))
|
|
;; a/b = (ua * 10^sb) / (ub * 10^sa) as an exact rational.
|
|
(jbd-rational->bigdec (/ (* (jbigdec-unscaled a) (expt 10 (jbigdec-scale b)))
|
|
(* (jbigdec-unscaled b) (expt 10 (jbigdec-scale a))))))
|
|
|
|
;; integer-division semantics (quot/rem): truncate toward zero, scale 0.
|
|
(define (jbd-int-quot a b)
|
|
(when (= 0 (jbigdec-unscaled b))
|
|
(jolt-throw (jolt-host-throwable "java.lang.ArithmeticException" "Divide by zero")))
|
|
(let-values (((ua ub s) (jbd-align a b))) (make-jbigdec (quotient ua ub) 0)))
|
|
(define (jbd-int-rem a b)
|
|
(when (= 0 (jbigdec-unscaled b))
|
|
(jolt-throw (jolt-host-throwable "java.lang.ArithmeticException" "Divide by zero")))
|
|
(let-values (((ua ub s) (jbd-align a b)))
|
|
(make-jbigdec (remainder ua ub) (max (jbigdec-scale a) (jbigdec-scale b)))))
|
|
|
|
;; scale-independent ordering: compare unscaled values aligned to a common scale.
|
|
(define (jbd-compare2 a b)
|
|
(let-values (((ua ub s) (jbd-align a b))) (cond ((< ua ub) -1) ((> ua ub) 1) (else 0))))
|
|
|
|
;; A binary op over operands that may mix bigdec / integer / flonum. flonum-op is
|
|
;; the native fallback for the double-contagion path; bd-op is the exact bigdec op.
|
|
(define (jbd-binop flonum-op bd-op a b)
|
|
(if (or (flonum? a) (flonum? b))
|
|
(flonum-op (if (jbigdec? a) (jbigdec->flonum a) a)
|
|
(if (jbigdec? b) (jbigdec->flonum b) b))
|
|
(bd-op (jbd-coerce a) (jbd-coerce b))))
|
|
|
|
;; --- variadic engine ops (Phase-2 emit targets + value-position folds) -------
|
|
(define (jbd-fold flonum-op bd-op init xs)
|
|
(let loop ((acc init) (rest xs))
|
|
(if (null? rest) acc (loop (jbd-binop flonum-op bd-op acc (car rest)) (cdr rest)))))
|
|
|
|
(define (jbd-add . xs)
|
|
(cond ((null? xs) (make-jbigdec 0 0))
|
|
((null? (cdr xs)) (car xs))
|
|
(else (jbd-fold + jbd2+ (car xs) (cdr xs)))))
|
|
(define (jbd-sub . xs)
|
|
(cond ((null? xs) (error #f "- needs at least 1 arg"))
|
|
((null? (cdr xs)) (if (jbigdec? (car xs)) (jbd-negate (car xs)) (- (car xs))))
|
|
(else (jbd-fold - jbd2- (car xs) (cdr xs)))))
|
|
(define (jbd-mul . xs)
|
|
(cond ((null? xs) (make-jbigdec 1 0))
|
|
((null? (cdr xs)) (car xs))
|
|
(else (jbd-fold * jbd2* (car xs) (cdr xs)))))
|
|
(define (jbd-div . xs)
|
|
(cond ((null? xs) (error #f "/ needs at least 1 arg"))
|
|
((null? (cdr xs)) (jbd-binop / jbd2-div (make-jbigdec 1 0) (car xs)))
|
|
(else (jbd-fold / jbd2-div (car xs) (cdr xs)))))
|
|
|
|
;; comparison / predicate helpers (Phase-2 emit targets). A flonum operand demotes
|
|
;; to the native comparison on the flonum values.
|
|
(define (jbd-cmp-num op flop a b)
|
|
(if (or (flonum? a) (flonum? b))
|
|
(flop (if (jbigdec? a) (jbigdec->flonum a) a) (if (jbigdec? b) (jbigdec->flonum b) b))
|
|
(op (jbd-compare2 (jbd-coerce a) (jbd-coerce b)) 0)))
|
|
(define (jbd-lt? a b) (jbd-cmp-num < < a b))
|
|
(define (jbd-gt? a b) (jbd-cmp-num > > a b))
|
|
(define (jbd-le? a b) (jbd-cmp-num <= <= a b))
|
|
(define (jbd-ge? a b) (jbd-cmp-num >= >= a b))
|
|
(define (jbd-zero? a) (= 0 (jbigdec-unscaled a)))
|
|
(define (jbd-pos? a) (> (jbigdec-unscaled a) 0))
|
|
(define (jbd-neg? a) (< (jbigdec-unscaled a) 0))
|
|
(define (jbd-quot a b) (jbd-int-quot (jbd-coerce a) (jbd-coerce b)))
|
|
(define (jbd-rem a b) (jbd-int-rem (jbd-coerce a) (jbd-coerce b)))
|
|
|
|
;; --- wire into the value model ----------------------------------------------
|
|
(def-var! "clojure.core" "bigdec" jolt-bigdec)
|
|
|
|
;; Value-position arithmetic: (reduce + bigs) / (apply * bigs) pass +/*/- // AS A
|
|
;; VALUE, which lowers to these shims (NOT the inlined hot-path native op). Extend
|
|
;; them to dispatch to the bigdec engine when a bigdec operand is present; ordinary
|
|
;; numeric folds hit the captured native path unchanged.
|
|
(define jbd-prev-add jolt-add)
|
|
(define jbd-prev-sub jolt-sub)
|
|
(define jbd-prev-mul jolt-mul)
|
|
(define jbd-prev-div jolt-div)
|
|
(define (jbd-any? xs) (and (pair? xs) (or (jbigdec? (car xs)) (jbd-any? (cdr xs)))))
|
|
(set! jolt-add (lambda xs (if (jbd-any? xs) (apply jbd-add xs) (apply jbd-prev-add xs))))
|
|
(set! jolt-sub (lambda xs (if (jbd-any? xs) (apply jbd-sub xs) (apply jbd-prev-sub xs))))
|
|
(set! jolt-mul (lambda xs (if (jbd-any? xs) (apply jbd-mul xs) (apply jbd-prev-mul xs))))
|
|
(set! jolt-div (lambda xs (if (jbd-any? xs) (apply jbd-div xs) (apply jbd-prev-div xs))))
|
|
|
|
;; compare: add a bigdec arm (enables compare / sort / sorted collections). A
|
|
;; bigdec vs a plain number compares by value; bigdec vs bigdec is scale-independent.
|
|
(define jbd-prev-compare jolt-compare)
|
|
(define (jbd-numberish? x) (or (jbigdec? x) (number? x)))
|
|
(set! jolt-compare
|
|
(lambda (a b)
|
|
(if (and (or (jbigdec? a) (jbigdec? b)) (jbd-numberish? a) (jbd-numberish? b))
|
|
(if (or (flonum? a) (flonum? b))
|
|
(let ((fa (if (jbigdec? a) (jbigdec->flonum a) a))
|
|
(fb (if (jbigdec? b) (jbigdec->flonum b) b)))
|
|
(cond ((< fa fb) -1) ((> fa fb) 1) (else 0)))
|
|
(jbd-compare2 (jbd-coerce a) (jbd-coerce b)))
|
|
(jbd-prev-compare a b))))
|
|
(def-var! "clojure.core" "compare" jolt-compare)
|
|
|
|
;; equality: a bigdec equals only another bigdec, by value (matching (= 3M 3) = false).
|
|
(register-eq-arm! (lambda (a b) (or (jbigdec? a) (jbigdec? b)))
|
|
(lambda (a b) (and (jbigdec? a) (jbigdec? b) (jbigdec=? a b))))
|
|
|
|
;; str drops the M; pr/pr-str keep it.
|
|
(register-str-render! jbigdec? jbigdec->string)
|
|
(register-pr-arm! jbigdec? (lambda (x) (string-append (jbigdec->string x) "M")))
|
|
|
|
;; class / decimal?
|
|
(register-class-arm! jbigdec? (lambda (x) "java.math.BigDecimal"))
|
|
(set! jolt-decimal? (lambda (x) (jbigdec? x)))
|
|
(def-var! "clojure.core" "decimal?" jolt-decimal?)
|