[bpt/guile.git] / module / language / tree-il / primitives.scm

;;; open-coding primitive procedures

;; Copyright (C) 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.

;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;; 
;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;;; Lesser General Public License for more details.
;;;; 
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

;;; Code:

(define-module (language tree-il primitives)
  #:use-module (system base pmatch)
  #:use-module (rnrs bytevectors)
  #:use-module (system base syntax)
  #:use-module (language tree-il)
  #:use-module (srfi srfi-4)
  #:use-module (srfi srfi-16)
  #:export (resolve-primitives add-interesting-primitive!
            expand-primitives
            effect-free-primitive? effect+exception-free-primitive?
            constructor-primitive? accessor-primitive?
            singly-valued-primitive? equality-primitive?
            bailout-primitive?
            negate-primitive))

;; When adding to this, be sure to update *multiply-valued-primitives*
;; if appropriate.
(define *interesting-primitive-names* 
  '(apply
    call-with-values
    call-with-current-continuation
    call/cc
    dynamic-wind
    values
    eq? eqv? equal?
    memq memv
    = < > <= >= zero?
    + * - / 1- 1+ quotient remainder modulo
    ash logand logior logxor lognot
    not
    pair? null? list? symbol? vector? string? struct? number? char? nil?

    procedure? thunk?

    complex? real? rational? inf? nan? integer? exact? inexact? even? odd?

    char<? char<=? char>=? char>?

    integer->char char->integer number->string string->number

    acons cons cons*

    list vector

    car cdr
    set-car! set-cdr!

    caar cadr cdar cddr

    caaar caadr cadar caddr cdaar cdadr cddar cdddr

    caaaar caaadr caadar caaddr cadaar cadadr caddar cadddr
    cdaaar cdaadr cdadar cdaddr cddaar cddadr cdddar cddddr

    vector-length vector-ref vector-set!
    variable-ref variable-set!
    variable-bound?

    fluid-ref fluid-set! with-fluid*

    call-with-prompt
    abort-to-prompt* abort-to-prompt
    make-prompt-tag

    throw error scm-error

    string-length string-ref string-set!

    struct-vtable make-struct struct-ref struct-set!

    bytevector-u8-ref bytevector-u8-set!
    bytevector-s8-ref bytevector-s8-set!
    u8vector-ref u8vector-set! s8vector-ref s8vector-set!
    
    bytevector-u16-ref bytevector-u16-set!
    bytevector-u16-native-ref bytevector-u16-native-set!
    bytevector-s16-ref bytevector-s16-set!
    bytevector-s16-native-ref bytevector-s16-native-set!
    u16vector-ref u16vector-set! s16vector-ref s16vector-set!
    
    bytevector-u32-ref bytevector-u32-set!
    bytevector-u32-native-ref bytevector-u32-native-set!
    bytevector-s32-ref bytevector-s32-set!
    bytevector-s32-native-ref bytevector-s32-native-set!
    u32vector-ref u32vector-set! s32vector-ref s32vector-set!
    
    bytevector-u64-ref bytevector-u64-set!
    bytevector-u64-native-ref bytevector-u64-native-set!
    bytevector-s64-ref bytevector-s64-set!
    bytevector-s64-native-ref bytevector-s64-native-set!
    u64vector-ref u64vector-set! s64vector-ref s64vector-set!
    
    bytevector-ieee-single-ref bytevector-ieee-single-set!
    bytevector-ieee-single-native-ref bytevector-ieee-single-native-set!
    bytevector-ieee-double-ref bytevector-ieee-double-set!
    bytevector-ieee-double-native-ref bytevector-ieee-double-native-set!
    f32vector-ref f32vector-set! f64vector-ref f64vector-set!))

(define (add-interesting-primitive! name)
  (hashq-set! *interesting-primitive-vars*
              (or (module-variable (current-module) name)
                  (error "unbound interesting primitive" name))
              name))

(define *interesting-primitive-vars* (make-hash-table))

(for-each add-interesting-primitive! *interesting-primitive-names*)

(define *primitive-constructors*
  ;; Primitives that return a fresh object.
  '(acons cons cons* list vector make-struct make-struct/no-tail
    make-prompt-tag))

(define *primitive-accessors*
  ;; Primitives that are pure, but whose result depends on the mutable
  ;; memory pointed to by their operands.
  '(vector-ref
    car cdr
    memq memv
    struct-ref
    string-ref
    bytevector-u8-ref bytevector-s8-ref
    bytevector-u16-ref bytevector-u16-native-ref
    bytevector-s16-ref bytevector-s16-native-ref
    bytevector-u32-ref bytevector-u32-native-ref
    bytevector-s32-ref bytevector-s32-native-ref
    bytevector-u64-ref bytevector-u64-native-ref
    bytevector-s64-ref bytevector-s64-native-ref
    bytevector-ieee-single-ref bytevector-ieee-single-native-ref
    bytevector-ieee-double-ref bytevector-ieee-double-native-ref))

(define *effect-free-primitives*
  `(values
    eq? eqv? equal?
    = < > <= >= zero?
    ash logand logior logxor lognot
    + * - / 1- 1+ quotient remainder modulo
    not
    pair? null? list? symbol? vector? struct? string? number? char? nil
    complex? real? rational? inf? nan? integer? exact? inexact? even? odd?
    char<? char<=? char>=? char>?
    integer->char char->integer number->string string->number
    struct-vtable
    string-length vector-length
    ;; These all should get expanded out by expand-primitives.
    caar cadr cdar cddr
    caaar caadr cadar caddr cdaar cdadr cddar cdddr
    caaaar caaadr caadar caaddr cadaar cadadr caddar cadddr
    cdaaar cdaadr cdadar cdaddr cddaar cddadr cdddar cddddr
    ,@*primitive-constructors*
    ,@*primitive-accessors*))

;; Like *effect-free-primitives* above, but further restricted in that they
;; cannot raise exceptions.
(define *effect+exception-free-primitives*
  '(values
    eq? eqv? equal?
    not
    pair? null? list? symbol? vector? struct? string? number? char?
    procedure? thunk?
    acons cons cons* list vector))

;; Primitives that don't always return one value.
(define *multiply-valued-primitives* 
  '(apply
    call-with-values
    call-with-current-continuation
    call/cc
    dynamic-wind
    values
    call-with-prompt
    @abort abort-to-prompt))

;; Procedures that cause a nonlocal, non-resumable abort.
(define *bailout-primitives*
  '(throw error scm-error))

;; Negatable predicates.
(define *negatable-primitives*
  '((even? . odd?)
    (exact? . inexact?)
    (< . >=)
    (> . <=)
    (char<? . char>=?)
    (char>? . char<=?)))

(define *equality-primitives*
  '(eq? eqv? equal?))

(define *effect-free-primitive-table* (make-hash-table))
(define *effect+exceptions-free-primitive-table* (make-hash-table))
(define *equality-primitive-table* (make-hash-table))
(define *multiply-valued-primitive-table* (make-hash-table))
(define *bailout-primitive-table* (make-hash-table))
(define *negatable-primitive-table* (make-hash-table))

(for-each (lambda (x)
            (hashq-set! *effect-free-primitive-table* x #t))
          *effect-free-primitives*)
(for-each (lambda (x) 
            (hashq-set! *effect+exceptions-free-primitive-table* x #t))
          *effect+exception-free-primitives*)
(for-each (lambda (x)
            (hashq-set! *equality-primitive-table* x #t))
          *equality-primitives*)
(for-each (lambda (x) 
            (hashq-set! *multiply-valued-primitive-table* x #t))
          *multiply-valued-primitives*)
(for-each (lambda (x)
            (hashq-set! *bailout-primitive-table* x #t))
          *bailout-primitives*)
(for-each (lambda (x)
            (hashq-set! *negatable-primitive-table* (car x) (cdr x))
            (hashq-set! *negatable-primitive-table* (cdr x) (car x)))
          *negatable-primitives*)

(define (constructor-primitive? prim)
  (memq prim *primitive-constructors*))
(define (accessor-primitive? prim)
  (memq prim *primitive-accessors*))
(define (effect-free-primitive? prim)
  (hashq-ref *effect-free-primitive-table* prim))
(define (effect+exception-free-primitive? prim)
  (hashq-ref *effect+exceptions-free-primitive-table* prim))
(define (equality-primitive? prim)
  (hashq-ref *equality-primitive-table* prim))
(define (singly-valued-primitive? prim)
  (not (hashq-ref *multiply-valued-primitive-table* prim)))
(define (bailout-primitive? prim)
  (hashq-ref *bailout-primitive-table* prim))
(define (negate-primitive prim)
  (hashq-ref *negatable-primitive-table* prim))

(define (resolve-primitives x mod)
  (define local-definitions
    (make-hash-table))

  (let collect-local-definitions ((x x))
    (record-case x
      ((<toplevel-define> name)
       (hashq-set! local-definitions name #t))
      ((<seq> head tail)
       (collect-local-definitions head)
       (collect-local-definitions tail))
      (else #f)))
  
  (post-order
   (lambda (x)
     (or
      (record-case x
        ((<toplevel-ref> src name)
         (and=> (and (not (hashq-ref local-definitions name))
                     (hashq-ref *interesting-primitive-vars*
                                (module-variable mod name)))
                (lambda (name) (make-primitive-ref src name))))
        ((<module-ref> src mod name public?)
         ;; for the moment, we're disabling primitive resolution for
         ;; public refs because resolve-interface can raise errors.
         (and=> (and=> (resolve-module mod)
                       (if public?
                           module-public-interface
                           identity))
                (lambda (m)
                  (and=> (hashq-ref *interesting-primitive-vars*
                                    (module-variable m name))
                         (lambda (name)
                           (make-primitive-ref src name))))))
        ((<call> src proc args)
         (and (primitive-ref? proc)
              (make-primcall src (primitive-ref-name proc) args)))
        (else #f))
      x))
   x))

\f

(define *primitive-expand-table* (make-hash-table))

(define (expand-primitives x)
  (pre-order
   (lambda (x)
     (record-case x
       ((<primcall> src name args)
        (let ((expand (hashq-ref *primitive-expand-table* name)))
          (or (and expand (apply expand src args))
              x)))
       (else x)))
   x))

;;; I actually did spend about 10 minutes trying to redo this with
;;; syntax-rules. Patches appreciated.
;;;
(define-macro (define-primitive-expander sym . clauses)
  (define (inline-args args)
    (let lp ((in args) (out '()))
      (cond ((null? in) `(list ,@(reverse out)))
            ((symbol? in) `(cons* ,@(reverse out) ,in))
            ((pair? (car in))
             (lp (cdr in)
                 (cons (if (eq? (caar in) 'quote)
                           `(make-const src ,@(cdar in))
                           `(make-primcall src ',(caar in)
                                           ,(inline-args (cdar in))))
                       out)))
            ((symbol? (car in))
             ;; assume it's locally bound
             (lp (cdr in) (cons (car in) out)))
            ((self-evaluating? (car in))
             (lp (cdr in) (cons `(make-const src ,(car in)) out)))
            (else
             (error "what what" (car in))))))
  (define (consequent exp)
    (cond
     ((pair? exp)
      (pmatch exp
        ((if ,test ,then ,else)
         `(if ,test
              ,(consequent then)
              ,(consequent else)))
        (else
         `(make-primcall src ',(car exp)
                         ,(inline-args (cdr exp))))))
     ((symbol? exp)
      ;; assume locally bound
      exp)
     ((number? exp)
      `(make-const src ,exp))
     ((not exp)
      ;; failed match
      #f)
     (else (error "bad consequent yall" exp))))
  `(hashq-set! *primitive-expand-table*
               ',sym
               (case-lambda
                ,@(let lp ((in clauses) (out '()))
                    (if (null? in)
                        (reverse (cons '(else #f) out))
                        (lp (cddr in)
                            (cons `((src . ,(car in))
                                    ,(consequent (cadr in))) out)))))))

(define-primitive-expander zero? (x)
  (= x 0))

;; FIXME: All the code that uses `const?' is redundant with `peval'.

(define-primitive-expander +
  () 0
  (x) (values x)
  (x y) (if (and (const? y)
                 (let ((y (const-exp y)))
                   (and (number? y) (exact? y) (= y 1))))
            (1+ x)
            (if (and (const? y)
                     (let ((y (const-exp y)))
                       (and (number? y) (exact? y) (= y -1))))
                (1- x)
                (if (and (const? x)
                         (let ((x (const-exp x)))
                           (and (number? x) (exact? x) (= x 1))))
                    (1+ y)
                    (+ x y))))
  (x y z . rest) (+ x (+ y z . rest)))
  
(define-primitive-expander *
  () 1
  (x) (values x)
  (x y z . rest) (* x (* y z . rest)))
  
(define-primitive-expander -
  (x) (- 0 x)
  (x y) (if (and (const? y)
                 (let ((y (const-exp y)))
                   (and (number? y) (exact? y) (= y 1))))
            (1- x)
            (- x y))
  (x y z . rest) (- x (+ y z . rest)))
  
(define-primitive-expander /
  (x) (/ 1 x)
  (x y z . rest) (/ x (* y z . rest)))
  
(define-primitive-expander logior
  () 0
  (x) (logior x 0)
  (x y) (logior x y)
  (x y z . rest) (logior x (logior y z . rest)))

(define-primitive-expander logand
  () -1
  (x) (logand x -1)
  (x y) (logand x y)
  (x y z . rest) (logand x (logand y z . rest)))

(define-primitive-expander caar (x) (car (car x)))
(define-primitive-expander cadr (x) (car (cdr x)))
(define-primitive-expander cdar (x) (cdr (car x)))
(define-primitive-expander cddr (x) (cdr (cdr x)))
(define-primitive-expander caaar (x) (car (car (car x))))
(define-primitive-expander caadr (x) (car (car (cdr x))))
(define-primitive-expander cadar (x) (car (cdr (car x))))
(define-primitive-expander caddr (x) (car (cdr (cdr x))))
(define-primitive-expander cdaar (x) (cdr (car (car x))))
(define-primitive-expander cdadr (x) (cdr (car (cdr x))))
(define-primitive-expander cddar (x) (cdr (cdr (car x))))
(define-primitive-expander cdddr (x) (cdr (cdr (cdr x))))
(define-primitive-expander caaaar (x) (car (car (car (car x)))))
(define-primitive-expander caaadr (x) (car (car (car (cdr x)))))
(define-primitive-expander caadar (x) (car (car (cdr (car x)))))
(define-primitive-expander caaddr (x) (car (car (cdr (cdr x)))))
(define-primitive-expander cadaar (x) (car (cdr (car (car x)))))
(define-primitive-expander cadadr (x) (car (cdr (car (cdr x)))))
(define-primitive-expander caddar (x) (car (cdr (cdr (car x)))))
(define-primitive-expander cadddr (x) (car (cdr (cdr (cdr x)))))
(define-primitive-expander cdaaar (x) (cdr (car (car (car x)))))
(define-primitive-expander cdaadr (x) (cdr (car (car (cdr x)))))
(define-primitive-expander cdadar (x) (cdr (car (cdr (car x)))))
(define-primitive-expander cdaddr (x) (cdr (car (cdr (cdr x)))))
(define-primitive-expander cddaar (x) (cdr (cdr (car (car x)))))
(define-primitive-expander cddadr (x) (cdr (cdr (car (cdr x)))))
(define-primitive-expander cdddar (x) (cdr (cdr (cdr (car x)))))
(define-primitive-expander cddddr (x) (cdr (cdr (cdr (cdr x)))))

(define-primitive-expander cons*
  (x) (values x)
  (x y) (cons x y)
  (x y . rest) (cons x (cons* y . rest)))

(define-primitive-expander acons (x y z)
  (cons (cons x y) z))

(define-primitive-expander call/cc (proc)
  (call-with-current-continuation proc))

(define-primitive-expander make-struct (vtable tail-size . args)
  (if (and (const? tail-size)
           (let ((n (const-exp tail-size)))
             (and (number? n) (exact? n) (zero? n))))
      (make-struct/no-tail vtable . args)
      #f))

(define-primitive-expander u8vector-ref (vec i)
  (bytevector-u8-ref vec i))
(define-primitive-expander u8vector-set! (vec i x)
  (bytevector-u8-set! vec i x))
(define-primitive-expander s8vector-ref (vec i)
  (bytevector-s8-ref vec i))
(define-primitive-expander s8vector-set! (vec i x)
  (bytevector-s8-set! vec i x))

(define-primitive-expander u16vector-ref (vec i)
  (bytevector-u16-native-ref vec (* i 2)))
(define-primitive-expander u16vector-set! (vec i x)
  (bytevector-u16-native-set! vec (* i 2) x))
(define-primitive-expander s16vector-ref (vec i)
  (bytevector-s16-native-ref vec (* i 2)))
(define-primitive-expander s16vector-set! (vec i x)
  (bytevector-s16-native-set! vec (* i 2) x))

(define-primitive-expander u32vector-ref (vec i)
  (bytevector-u32-native-ref vec (* i 4)))
(define-primitive-expander u32vector-set! (vec i x)
  (bytevector-u32-native-set! vec (* i 4) x))
(define-primitive-expander s32vector-ref (vec i)
  (bytevector-s32-native-ref vec (* i 4)))
(define-primitive-expander s32vector-set! (vec i x)
  (bytevector-s32-native-set! vec (* i 4) x))

(define-primitive-expander u64vector-ref (vec i)
  (bytevector-u64-native-ref vec (* i 8)))
(define-primitive-expander u64vector-set! (vec i x)
  (bytevector-u64-native-set! vec (* i 8) x))
(define-primitive-expander s64vector-ref (vec i)
  (bytevector-s64-native-ref vec (* i 8)))
(define-primitive-expander s64vector-set! (vec i x)
  (bytevector-s64-native-set! vec (* i 8) x))

(define-primitive-expander f32vector-ref (vec i)
  (bytevector-ieee-single-native-ref vec (* i 4)))
(define-primitive-expander f32vector-set! (vec i x)
  (bytevector-ieee-single-native-set! vec (* i 4) x))
(define-primitive-expander f32vector-ref (vec i)
  (bytevector-ieee-single-native-ref vec (* i 4)))
(define-primitive-expander f32vector-set! (vec i x)
  (bytevector-ieee-single-native-set! vec (* i 4) x))

(define-primitive-expander f64vector-ref (vec i)
  (bytevector-ieee-double-native-ref vec (* i 8)))
(define-primitive-expander f64vector-set! (vec i x)
  (bytevector-ieee-double-native-set! vec (* i 8) x))
(define-primitive-expander f64vector-ref (vec i)
  (bytevector-ieee-double-native-ref vec (* i 8)))
(define-primitive-expander f64vector-set! (vec i x)
  (bytevector-ieee-double-native-set! vec (* i 8) x))

;; Appropriate for use with either 'eqv?' or 'equal?'.
(define maybe-simplify-to-eq
  (case-lambda
    ((src a b)
     ;; Simplify cases where either A or B is constant.
     (define (maybe-simplify a b)
       (and (const? a)
            (let ((v (const-exp a)))
              (and (or (memq v '(#f #t () #nil))
                       (symbol? v)
                       (and (integer? v)
                            (exact? v)
                            (<= v most-positive-fixnum)
                            (>= v most-negative-fixnum)))
                   (make-primcall src 'eq? (list a b))))))
     (or (maybe-simplify a b) (maybe-simplify b a)))
    (else #f)))

(hashq-set! *primitive-expand-table* 'eqv?   maybe-simplify-to-eq)
(hashq-set! *primitive-expand-table* 'equal? maybe-simplify-to-eq)

(hashq-set! *primitive-expand-table*
            'call-with-prompt
            (case-lambda
              ((src tag thunk handler)
               (let ((handler-sym (gensym))
                     (args-sym (gensym)))
                 (make-let
                  src '(handler) (list handler-sym) (list handler)
                  (make-prompt
                   src tag (make-call #f thunk '())
                   ;; If handler itself is a lambda, the inliner can do some
                   ;; trickery here.
                   (make-lambda-case
                    (tree-il-src handler) '() #f 'args #f '() (list args-sym)
                    (make-primcall
                     #f 'apply
                     (list (make-lexical-ref #f 'handler handler-sym)
                           (make-lexical-ref #f 'args args-sym)))
                    #f)))))
              (else #f)))

(hashq-set! *primitive-expand-table*
            'abort-to-prompt*
            (case-lambda
              ((src tag tail-args)
               (make-abort src tag '() tail-args))
              (else #f)))
(hashq-set! *primitive-expand-table*
            'abort-to-prompt
            (case-lambda
              ((src tag . args)
               (make-abort src tag args (make-const #f '())))
              (else #f)))