1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-05-16 18:50:23 +02:00
guile/module/system/il/compile.scm
Andy Wingo d51406fe87 lambda-lifting for (lambda () ...) as consumer of call-with-values
* libguile/vm-engine.c (vm_run): Add new error case,
  vm_error_not_enough_values.

* libguile/vm-i-system.c (goto/nargs, call/nargs): So, in these cases, if
  we get too many values, we don't truncate the values like we do in the
  single-value continuation case, or in the mvbind case. What to do? I
  guess we either truncate them here, or only allow the correct number of
  values. Dunno. Mark the code as a fixme.
  (truncate-values): New instruction, for mv-bind: checks that the number
  of values on the stack is compatible with the number of bindings we
  have arranged for them, truncating if necessary.

* module/language/scheme/translate.scm (custom-transformer-table):
  Compile receive as a primary form -- not so much because it is a
  primary form, but more to test the mv-bind machinery. Also it's more
  efficient, I think.

* module/system/il/compile.scm (lift-variables!): New helper, factored
  out of `optimize'.
  (optimize): Add a few more cases. Adapt `lambda' optimization, which
  isn't much. I'm not happy with ghil as a mungeable language.
  Add a case for call-with-values with the second argument is
  a lambda: lift the lambda. Untested.
  (codegen): Refactor the push-bindings! code. Compile mv-bind.

* module/system/il/ghil.scm (<ghil-mv-bind>): Add mv-bind construct,
  along with its procedures.

* module/system/il/glil.scm (<glil-mv-bind>): Add mv-bind construct,
  different from the high-level one. It makes sense in the source, I
  think.

* module/system/vm/assemble.scm (codegen): Assemble glil-mv-bind by
  pushing onto the bindings list, and actually push some code to truncate
  the values.
2008-09-18 22:49:55 +02:00

424 lines
14 KiB
Scheme
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

;;; GHIL -> GLIL compiler
;; Copyright (C) 2001 Free Software Foundation, Inc.
;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.
;;
;; This program 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 General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with this program; see the file COPYING. If not, write to
;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
;;; Code:
(define-module (system il compile)
#:use-syntax (system base syntax)
#:use-module (system il glil)
#:use-module (system il ghil)
#:use-module (ice-9 common-list)
#:export (compile))
(define (compile x e . opts)
(if (memq #:O opts) (set! x (optimize x)))
(codegen x))
;;;
;;; Stage 2: Optimization
;;;
(define (lift-variables! env)
(let ((parent-env (ghil-env-parent env)))
(for-each (lambda (v)
(case (ghil-var-kind v)
((argument) (set! (ghil-var-kind v) 'local)))
(set! (ghil-var-env v) parent-env)
(ghil-env-add! parent-env v))
(ghil-env-variables env))))
(define (optimize x)
(record-case x
((<ghil-set> env loc var val)
(make-ghil-set env var (optimize val)))
((<ghil-define> env loc var val)
(make-ghil-define env var (optimize val)))
((<ghil-if> env loc test then else)
(make-ghil-if env loc (optimize test) (optimize then) (optimize else)))
((<ghil-and> env loc exps)
(make-ghil-and env loc (map optimize exps)))
((<ghil-or> env loc exps)
(make-ghil-or env loc (map optimize exps)))
((<ghil-begin> env loc exps)
(make-ghil-begin env loc (map optimize exps)))
((<ghil-bind> env loc vars vals body)
(make-ghil-bind env loc vars (map optimize vals) (optimize body)))
((<ghil-lambda> env loc vars rest meta body)
(make-ghil-lambda env loc vars rest meta (optimize body)))
((<ghil-inline> env loc instruction args)
(make-ghil-inline env loc instruction (map optimize args)))
((<ghil-call> env loc proc args)
(let ((parent-env env))
(record-case proc
;; ((@lambda (VAR...) BODY...) ARG...) =>
;; (@let ((VAR ARG) ...) BODY...)
((<ghil-lambda> env loc vars rest meta body)
(cond
((not rest)
(lift-variables! env)
(make-ghil-bind parent-env loc (map optimize args)))
(else
(make-ghil-call parent-env loc (optimize proc) (map optimize args)))))
(else
(make-ghil-call parent-env loc (optimize proc) (map optimize args))))))
((<ghil-mv-call> env loc producer consumer)
(record-case consumer
;; (mv-call PRODUCER (lambda ARGS BODY...)) =>
;; (mv-let PRODUCER ARGS BODY...)
((<ghil-lambda> env loc vars rest meta body)
(lift-variables! env)
(make-ghil-mv-bind producer vars rest body))
(else
(make-ghil-mv-call env loc (optimize producer) (optimize consumer)))))
(else x)))
;;;
;;; Stage 3: Code generation
;;;
(define *ia-void* (make-glil-void))
(define *ia-drop* (make-glil-call 'drop 0))
(define *ia-return* (make-glil-call 'return 0))
(define (make-label) (gensym ":L"))
(define (make-glil-var op env var)
(case (ghil-var-kind var)
((argument)
(make-glil-argument op (ghil-var-index var)))
((local)
(make-glil-local op (ghil-var-index var)))
((external)
(do ((depth 0 (1+ depth))
(e env (ghil-env-parent e)))
((eq? e (ghil-var-env var))
(make-glil-external op depth (ghil-var-index var)))))
((module)
(make-glil-module op (ghil-var-env var) (ghil-var-name var)))
(else (error "Unknown kind of variable:" var))))
(define (constant? x)
(cond ((or (number? x) (string? x) (symbol? x) (keyword? x) (boolean? x)) #t)
((pair? x) (and (constant? (car x))
(constant? (cdr x))))
((vector? x) (let lp ((i (vector-length x)))
(or (zero? i)
(and (constant? (vector-ref x (1- i)))
(lp (1- i))))))))
(define (codegen ghil)
(let ((stack '()))
(define (push-code! loc code)
(set! stack (cons code stack))
(if loc (set! stack (cons (make-glil-source loc) stack))))
(define (var->binding var)
(list (ghil-var-name var) (ghil-var-kind var) (ghil-var-index var)))
(define (push-bindings! loc vars)
(if (not (null? vars))
(push-code! loc (make-glil-bind (map var->binding vars)))))
(define (comp tree tail drop)
(define (push-label! label)
(push-code! #f (make-glil-label label)))
(define (push-branch! loc inst label)
(push-code! loc (make-glil-branch inst label)))
(define (push-call! loc inst args)
(for-each comp-push args)
(push-code! loc (make-glil-call inst (length args))))
;; possible tail position
(define (comp-tail tree) (comp tree tail drop))
;; push the result
(define (comp-push tree) (comp tree #f #f))
;; drop the result
(define (comp-drop tree) (comp tree #f #t))
;; drop the result if unnecessary
(define (maybe-drop)
(if drop (push-code! #f *ia-drop*)))
;; return here if necessary
(define (maybe-return)
(if tail (push-code! #f *ia-return*)))
;; return this code if necessary
(define (return-code! loc code)
(if (not drop) (push-code! loc code))
(maybe-return))
;; return void if necessary
(define (return-void!)
(return-code! #f *ia-void*))
;; return object if necessary
(define (return-object! loc obj)
(return-code! loc (make-glil-const #:obj obj)))
;;
;; dispatch
(record-case tree
((<ghil-void>)
(return-void!))
((<ghil-quote> env loc obj)
(return-object! loc obj))
((<ghil-quasiquote> env loc exp)
(let loop ((x exp))
(cond
((list? x)
(push-call! #f 'mark '())
(for-each loop x)
(push-call! #f 'list-mark '()))
((pair? x)
(loop (car x))
(loop (cdr x))
(push-code! #f (make-glil-call 'cons 2)))
((record? x)
(record-case x
((<ghil-unquote> env loc exp)
(comp-push exp))
((<ghil-unquote-splicing> env loc exp)
(comp-push exp)
(push-call! #f 'list-break '()))))
((constant? x)
(push-code! #f (make-glil-const #:obj x)))
(else
(error "element of quasiquote can't be compiled" x))))
(maybe-drop)
(maybe-return))
((<ghil-ref> env loc var)
(return-code! loc (make-glil-var 'ref env var)))
((<ghil-set> env loc var val)
(comp-push val)
(push-code! loc (make-glil-var 'set env var))
(return-void!))
((<ghil-define> env loc var val)
(comp-push val)
(push-code! loc (make-glil-var 'define env var))
(return-void!))
((<ghil-if> env loc test then else)
;; TEST
;; (br-if-not L1)
;; THEN
;; (br L2)
;; L1: ELSE
;; L2:
(let ((L1 (make-label)) (L2 (make-label)))
(comp-push test)
(push-branch! loc 'br-if-not L1)
(comp-tail then)
(if (not tail) (push-branch! #f 'br L2))
(push-label! L1)
(comp-tail else)
(if (not tail) (push-label! L2))))
((<ghil-and> env loc exps)
;; EXP
;; (br-if-not L1)
;; ...
;; TAIL
;; (br L2)
;; L1: (const #f)
;; L2:
(cond ((null? exps) (return-object! loc #t))
((null? (cdr exps)) (comp-tail (car exps)))
(else
(let ((L1 (make-label)) (L2 (make-label)))
(let lp ((exps exps))
(cond ((null? (cdr exps))
(comp-tail (car exps))
(push-branch! #f 'br L2)
(push-label! L1)
(return-object! #f #f)
(push-label! L2)
(maybe-return))
(else
(comp-push (car exps))
(push-branch! #f 'br-if-not L1)
(lp (cdr exps)))))))))
((<ghil-or> env loc exps)
;; EXP
;; (dup)
;; (br-if L1)
;; (drop)
;; ...
;; TAIL
;; L1:
(cond ((null? exps) (return-object! loc #f))
((null? (cdr exps)) (comp-tail (car exps)))
(else
(let ((L1 (make-label)))
(let lp ((exps exps))
(cond ((null? (cdr exps))
(comp-tail (car exps))
(push-label! L1)
(maybe-return))
(else
(comp-push (car exps))
(if (not drop)
(push-call! #f 'dup '()))
(push-branch! #f 'br-if L1)
(if (not drop)
(push-call! #f 'drop '()))
(lp (cdr exps)))))))))
((<ghil-begin> env loc exps)
;; EXPS...
;; TAIL
(if (null? exps)
(return-void!)
(do ((exps exps (cdr exps)))
((null? (cdr exps))
(comp-tail (car exps)))
(comp-drop (car exps)))))
((<ghil-bind> env loc vars vals body)
;; VALS...
;; (set VARS)...
;; BODY
(for-each comp-push vals)
(push-bindings! loc vars)
(for-each (lambda (var) (push-code! #f (make-glil-var 'set env var)))
(reverse vars))
(comp-tail body)
(push-code! #f (make-glil-unbind)))
((<ghil-mv-bind> env loc producer vars rest body)
;; VALS...
;; (set VARS)...
;; BODY
(let ((MV (make-label)))
(comp-push producer)
(push-code! loc (make-glil-mv-call 0 MV))
(push-code! #f (make-glil-const #:obj 1))
(push-label! MV)
(push-code! #f (make-glil-mv-bind (map var->binding vars) rest))
(for-each (lambda (var) (push-code! #f (make-glil-var 'set env var)))
(reverse vars)))
(comp-tail body)
(push-code! #f (make-glil-unbind)))
((<ghil-lambda> env loc vars rest meta body)
(return-code! loc (codegen tree)))
((<ghil-inline> env loc inline args)
;; ARGS...
;; (INST NARGS)
;; FIXME: translate between call and goto/args, etc
(push-call! loc inline args)
(maybe-drop)
(maybe-return))
((<ghil-values> env loc values)
(cond (tail ;; (lambda () (values 1 2))
(push-call! loc 'return/values values))
(drop ;; (lambda () (values 1 2) 3)
(for-each comp-drop values))
(else ;; (lambda () (list (values 10 12) 1))
(push-code! #f (make-glil-const #:obj 'values))
(push-code! #f (make-glil-call #:inst 'link-now #:nargs 1))
(push-code! #f (make-glil-call #:inst 'variable-ref #:nargs 0))
(push-call! loc 'call values))))
((<ghil-values*> env loc values)
(cond (tail ;; (lambda () (apply values '(1 2)))
(push-call! loc 'return/values* values))
(drop ;; (lambda () (apply values '(1 2)) 3)
(for-each comp-drop values))
(else ;; (lambda () (list (apply values '(10 12)) 1))
(push-code! #f (make-glil-const #:obj 'values))
(push-code! #f (make-glil-call #:inst 'link-now #:nargs 1))
(push-code! #f (make-glil-call #:inst 'variable-ref #:nargs 0))
(push-call! loc 'apply values))))
((<ghil-call> env loc proc args)
;; PROC
;; ARGS...
;; ([tail-]call NARGS)
(comp-push proc)
(push-call! loc (if tail 'goto/args 'call) args)
(maybe-drop))
((<ghil-mv-call> env loc producer consumer)
;; CONSUMER
;; PRODUCER
;; (mv-call MV)
;; ([tail]-call 1)
;; goto POST
;; MV: [tail-]call/nargs
;; POST: (maybe-drop)
(let ((MV (make-label)) (POST (make-label)))
(comp-push consumer)
(comp-push producer)
(push-code! loc (make-glil-mv-call 0 MV))
(push-code! loc (make-glil-call (if tail 'goto/args 'call) 1))
(cond ((not tail)
(push-branch! #f 'br POST)))
(push-label! MV)
(push-code! loc (make-glil-call (if tail 'goto/nargs 'call/nargs) 0))
(cond ((not tail)
(push-label! POST)
(maybe-drop)))))))
;;
;; main
(record-case ghil
((<ghil-lambda> env loc vars rest meta body)
(let* ((evars (ghil-env-variables env))
(locs (pick (lambda (v) (eq? (ghil-var-kind v) 'local)) evars))
(exts (pick (lambda (v) (eq? (ghil-var-kind v) 'external)) evars)))
;; initialize variable indexes
(finalize-index! vars)
(finalize-index! locs)
(finalize-index! exts)
;; meta bindings
(push-bindings! #f vars)
;; export arguments
(do ((n 0 (1+ n))
(l vars (cdr l)))
((null? l))
(let ((v (car l)))
(case (ghil-var-kind v)
((external)
(push-code! #f (make-glil-argument 'ref n))
(push-code! #f (make-glil-external 'set 0 (ghil-var-index v)))))))
;; compile body
(comp body #t #f)
;; create GLIL
(let ((vars (make-glil-vars #:nargs (length vars)
#:nrest (if rest 1 0)
#:nlocs (length locs)
#:nexts (length exts))))
(make-glil-asm vars meta (reverse! stack))))))))
(define (finalize-index! list)
(do ((n 0 (1+ n))
(l list (cdr l)))
((null? l))
(let ((v (car l))) (set! (ghil-var-index v) n))))