scsh-0.6/ps-compiler/prescheme/primop/c-base.scm

344 lines
11 KiB
Scheme

; Copyright (c) 1994 by Richard Kelsey. See file COPYING.
(define-c-generator let #f
(lambda (call port indent)
(let ((args (call-args call))
(vars (lambda-variables (call-arg call 0))))
(do ((i 1 (+ i 1))
(vars vars (cdr vars)))
((null? vars))
(let ((val (vector-ref args i)))
(if (not (lambda-node? val))
(c-assignment (car vars) val port indent)))))))
(define-c-generator letrec1 #f
(lambda (call port indent)
(values)))
(define-c-generator letrec2 #f
(lambda (call port indent)
(values)))
(define-c-generator jump #f
(lambda (call port indent)
(let ((proc (called-lambda call)))
(assign-argument-vars (lambda-variables proc) call 1 port indent)
(indent-to port indent)
(display "goto " port)
(writec port #\L)
(display (lambda-id proc) port)
(write-char #\; port)
(note-jump-generated! proc)
(values))))
(define (assign-argument-vars vars call start port indent)
(really-assign-argument-vars vars call start "arg" port indent))
(define (assign-merged-argument-vars vars call start port indent)
(really-assign-argument-vars vars call start "merged_arg" port indent))
(define (assign-global-argument-vars vars call start port indent)
(really-assign-argument-vars vars call start "goto_arg" port indent))
(define (really-assign-argument-vars vars call start name port indent)
(let ((args (call-args call)))
(do ((i start (+ i 1))
(vars vars (cdr vars)))
((>= i (vector-length args)))
(if (not (or (undefined-value-node? (vector-ref args i))
(eq? type/unit (get-variable-type (car vars)))))
(c-assignment (c-argument-var name
(get-variable-type (car vars))
(- i start)
port)
(vector-ref args i)
port indent)))))
; Calls
; Unknown calls have a first argument of 'goto if they are supposed to be
; tail-recursive. For known calls the protocol field of the lambda node
; is set to 'tail-called if any of the calls are supposed to be tail-recursive.
;
; Calls to non-tail-called procedures are just regular C calls. For tail-
; called procedures there are two kinds of calls:
; Tail-call from a tail-called procedure: proceed through the driver loop
; All others: start a driver loop
;
; Known and unknown calls are handled identically, except that known calls
; may be to merged procedures.
;
; Merged procedures with GOTO calls:
; This works if we merge the return points as well. Possibly there should be
; one return switch per C procedure. There do have to be separate return point
; variables (and one global one for the switch).
(define-c-generator call #f
(lambda (call port indent)
(cond ((merged-procedure-reference (call-arg call 1))
=> (lambda (form)
(generate-merged-call call 2 form port indent)))
(else
(generate-c-call call 2 port indent)))))
(define-c-generator tail-call #f
(lambda (call port indent)
(cond ((merged-procedure-reference (call-arg call 1))
=> (lambda (form)
(generate-merged-goto-call call 2 form port indent)))
(else
(generate-c-tail-call call 2 port indent)))))
(define-c-generator unknown-call #f
(lambda (call port indent)
(if (goto-protocol? (literal-value (call-arg call 2)))
(user-warning "ignoring GOTO declaration for non-tail-recursive call to"
(variable-name (reference-variable
(call-arg call 1)))))
(generate-c-call call 3 port indent)))
(define-c-generator unknown-tail-call #f
(lambda (call port indent)
(generate-c-tail-call call 3 port indent)))
(define (generate-merged-goto-call call start form port indent)
(let ((proc (form-value form)))
(assign-merged-argument-vars (cdr (lambda-variables proc))
call start
port indent)
(indent-to port indent)
(display "goto " port)
(display (form-c-name form) port)
(write-char #\; port)
(values)))
(define (generate-goto-call call start port indent)
(let ((proc (call-arg call 1)))
(if (not (global-reference? proc))
(bug "incorrect procedure in goto call ~S" call))
(assign-global-argument-vars (cdr (lambda-variables
(global-lambda
(reference-variable proc))))
call start
port indent)
; T is the marker for the tail-call version of the procedure
(indent-to port indent)
(display "return((long)T" port)
(c-value proc port)
(display ");" port)))
(define (global-lambda var)
(let ((form (maybe-variable->form var)))
(if (and form
(or (eq? 'lambda (form-type form))
(eq? 'merged (form-type form))))
(form-value form)
(bug "value of ~S, called using goto, is not a known procedure"
var))))
; C requires that we dereference all but calls to global functions.
; Calls to literals are macros that must take care of themselves.
(define (generate-c-call call start port indent)
(let ((vars (lambda-variables (call-arg call 0)))
(args (call-args call))
(proc (call-arg call 1)))
(if (and (global-reference? proc)
(memq? 'tail-called (variable-flags (reference-variable proc))))
(call-with-driver-loop call start port indent (car vars))
(let ((deref? (or (and (reference-node? proc)
(variable-binder (reference-variable proc)))
(call-node? proc))))
(c-assign-to-variable (car vars) port indent)
(if deref?
(display "(*" port))
(c-value proc port)
(if deref?
(writec port #\)))
(write-value+result-var-list args start (cdr vars) port)))
(writec port #\;)
(values)))
(define (generate-c-tail-call call start port indent)
(let ((proc (call-arg call 1))
(args (call-args call)))
(cond ((not (and (global-reference? proc)
(memq? 'tail-called
(variable-flags (reference-variable proc)))))
(indent-to port indent)
(display "return " port)
(c-value proc port)
(write-value-list-with-extras args start *extra-tail-call-args* port))
(*doing-tail-called-procedure?*
(generate-goto-call call start port indent))
(else
(call-with-driver-loop call start port indent #f)))
(writec port #\;)
(values)))
(define (global-reference? node)
(and (reference-node? node)
(global-variable? (reference-variable node))))
(define (call-with-driver-loop call start port indent result-var)
(let* ((proc-var (reference-variable (call-arg call 1)))
(vars (lambda-variables (global-lambda proc-var))))
(assign-global-argument-vars (cdr vars) call start port indent)
(if result-var
(c-assign-to-variable result-var port indent)
(begin
(indent-to port indent)
(display "return " port)))
(display "TTrun_machine((long)" port)
(display "T" port)
(write-c-identifier (variable-name proc-var) port)
(display ")" port)))
(define (generate-merged-call call start form port indent)
(let ((return-index (form-return-count form))
(name (form-c-name form))
(res (lambda-variables (call-arg call 0))))
(set-form-return-count! form (+ 1 return-index))
(assign-merged-argument-vars (cdr (lambda-variables (form-value form)))
call start port indent)
(indent-to port indent)
(format port "~A_return_tag = ~D;" name return-index)
(indent-to port indent)
(format port "goto ~A;" name)
(indent-to port (- indent 1))
(format port "~A_return_~S:" name return-index)
(do ((i 0 (+ i 1))
(res res (cdr res)))
((null? res))
(let ((var (car res)))
(cond ((and (used? var)
(let ((type (get-variable-type var)))
(and (not (eq? type type/unit))
(not (eq? type type/null)))))
(c-assign-to-variable var port indent)
(format port "~A~D_return_value;" name i)))))))
; Returns
(define-c-generator return #f
(lambda (call port indent)
(if *current-merged-procedure*
(generate-return-from-merged-call call 1 port indent)
(really-generate-c-return call 1 port indent))))
(define-c-generator unknown-return #f
(lambda (call port indent)
(cond (*doing-tail-called-procedure?*
(generate-return-from-tail-call call port indent))
(*current-merged-procedure*
(generate-return-from-merged-call call 1 port indent))
(else
(really-generate-c-return call 1 port indent)))))
(define (generate-return-from-tail-call call port indent)
(if (not (no-value-node? (call-arg call 1)))
(c-assignment "TTreturn_value" (call-arg call 1) port indent))
(indent-to port indent)
(display "return(0L);" port))
(define (generate-return-from-merged-call call start port indent)
(let ((name *current-merged-procedure*))
(do ((i start (+ i 1)))
((= i (call-arg-count call)))
(let ((arg (call-arg call i)))
(if (not (no-value-node? arg))
(c-assignment (format #f "~A~D_return_value" name (- i start))
arg port indent))))
(indent-to port indent)
(format port "goto ~A_return;" name)))
(define (really-generate-c-return call start port indent)
(do ((i (+ start 1) (+ i 1)))
((= i (call-arg-count call)))
(let ((arg (call-arg call i)))
(if (not (no-value-node? arg))
(begin
(indent-to port indent)
(format port "*TT~D = " (- (- i start) 1))
(c-value arg port)
(write-char #\; port)))))
(indent-to port indent)
(display "return" port)
(if (not (no-value-node? (call-arg call start)))
(begin
(write-char #\space port)
(c-value (call-arg call start) port)))
(display ";" port)
(values))
; Allocate
;(define-c-generator allocate #f
; (lambda (call port indent)
; (let ((cont (call-arg call 0))
; (size (call-arg call 1)))
; (c-assign-to-variable (car (lambda-variables cont)) port indent)
; (display "(long) malloc(" port)
; (c-value size port)
; (display "* sizeof(char));" port))))
(define-c-generator global-ref #t
(lambda (call port indent)
(c-value (call-arg call 0) port)))
(define-c-generator global-set! #f
(lambda (call port indent)
(let ((value (call-arg call 2)))
(if (not (and (literal-node? value)
(unspecific? (literal-value value))))
(c-assignment (reference-variable (call-arg call 1))
value
port indent)))))
; if (ARG1 OP ARG2) {
; cont1 }
; else {
; cont2 }
(define-c-generator test #f
(lambda (call port indent)
(destructure ((#(cont1 cont2 value) (call-args call)))
(generate-c-conditional-prelude port indent)
(c-value value port)
(generate-c-conditional-jumps cont1 cont2 port indent))))
(define (generate-c-conditional-prelude port indent)
(indent-to port indent)
(display "if " port)
(writec port #\())
(define (generate-c-conditional-jumps cont1 cont2 port indent)
(display ") {" port)
(write-c-block (lambda-body cont1) port (+ indent 2))
(newline port)
(indent-to port indent)
(display "else {" port)
(write-c-block (lambda-body cont2) port (+ indent 2)))
(define-c-generator unspecific #t
(lambda (call port indent)
(bug "generating code for undefined value ~S" call)))
(define-c-generator uninitialized-value #t
(lambda (call port indent)
(bug "generating code for uninitialized value ~S" call)))
(define-c-generator null-pointer? #t
(lambda (call port indent)
(display "NULL == " port)
(c-value (call-arg call 0) port)))
(define-c-generator null-pointer #t
(lambda (call port indent)
(display "NULL" port)))
(define-c-generator eq? #t
(lambda (call port indent)
(simple-c-primop "==" call port)))