#| -*-Scheme-*-

$Id: rules4.scm,v 4.19 2007/01/05 21:19:20 cph Exp $

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    2006, 2007 Massachusetts Institute of Technology

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|#

;;;; LAP Generation Rules: Interpreter Calls
;;; package: (compiler lap-syntaxer)

(declare (usual-integrations))

;;;; Variable cache trap handling.

(define-rule statement
  (INTERPRETER-CALL:CACHE-REFERENCE (? cont) (? extension) (? safe?))
  (QUALIFIER (interpreter-call-argument? extension))
  cont					; ignored
  (let ((set-extension
	 (interpreter-call-argument->machine-register! extension d2)))
    (let ((clear-map (clear-map!)))
      (LAP ,@set-extension
	   ,@clear-map
	   (JSR ,(if safe?
		     entry:compiler-safe-reference-trap
		     entry:compiler-reference-trap))))))

(define-rule statement
  (INTERPRETER-CALL:CACHE-ASSIGNMENT (? cont) (? extension) (? value))
  (QUALIFIER (and (interpreter-call-argument? extension)
		  (interpreter-call-argument? value)))
  cont					; ignored
  (let ((set-extension
	 (interpreter-call-argument->machine-register! extension d2)))
    (let ((set-value (interpreter-call-argument->machine-register! value d3)))
      (let ((clear-map (clear-map!)))
	(LAP ,@set-extension
	     ,@set-value
	     ,@clear-map
	     (JSR ,entry:compiler-assignment-trap))))))

(define-rule statement
  (INTERPRETER-CALL:CACHE-UNASSIGNED? (? cont) (? extension))
  (QUALIFIER (interpreter-call-argument? extension))
  cont					; ignored
  (let ((set-extension
	 (interpreter-call-argument->machine-register! extension d2)))
    (let ((clear-map (clear-map!)))
      (LAP ,@set-extension
	   ,@clear-map
	   ,@(invoke-interface-jsr code:compiler-unassigned?-trap)))))

;;;; Interpreter Calls

;;; All the code that follows is obsolete.  It hasn't been used in a while.
;;; It is provided in case the relevant switches are turned off, but there
;;; is no real reason to do this.  Perhaps the switches should be removed.

(define (interpreter-call-argument? expression)
  (or (rtl:register? expression)
      (rtl:constant? expression)
      (and (rtl:cons-pointer? expression)
	   (rtl:machine-constant? (rtl:cons-pointer-type expression))
	   (rtl:machine-constant? (rtl:cons-pointer-datum expression)))
      (rtl:simple-offset? expression)))

(define (interpreter-call-argument->machine-register! expression register)
  (let ((target (register-reference register)))
    (case (car expression)
      ((REGISTER)
       (load-machine-register! (rtl:register-number expression) register))
      ((CONSTANT)
       (LAP ,@(clear-registers! register)
	    ,@(load-constant (rtl:constant-value expression) target)))
      ((CONS-POINTER)
       (LAP ,@(clear-registers! register)
	    ,@(load-non-pointer (rtl:machine-constant-value
				 (rtl:cons-pointer-type expression))
				(rtl:machine-constant-value
				 (rtl:cons-pointer-datum expression))
				target)))
      ((OFFSET)
       (let ((source-reference (offset->reference! expression)))
	 (LAP ,@(clear-registers! register)
	      (MOV L ,source-reference ,target))))
      (else
       (error "Unknown expression type" (car expression))))))

(define-rule statement
  (INTERPRETER-CALL:ACCESS (? cont) (? environment) (? name))
  (QUALIFIER (interpreter-call-argument? environment))
  cont					; ignored
  (lookup-call code:compiler-access environment name))

(define-rule statement
  (INTERPRETER-CALL:LOOKUP (? cont) (? environment) (? name) (? safe?))
  (QUALIFIER (interpreter-call-argument? environment))
  cont					; ignored
  (lookup-call (if safe? code:compiler-safe-lookup code:compiler-lookup)
	       environment name))

(define-rule statement
  (INTERPRETER-CALL:UNASSIGNED? (? cont) (? environment) (? name))
  (QUALIFIER (interpreter-call-argument? environment))
  cont					; ignored
  (lookup-call code:compiler-unassigned? environment name))

(define-rule statement
  (INTERPRETER-CALL:UNBOUND? (? cont) (? environment) (? name))
  (QUALIFIER (interpreter-call-argument? environment))
  cont					; ignored
  (lookup-call code:compiler-unbound? environment name))

(define (lookup-call code environment name)
  (let ((set-environment
	 (interpreter-call-argument->machine-register! environment d2)))
    (let ((clear-map (clear-map!)))
      (LAP ,@set-environment
	   ,@clear-map
	   ,@(load-constant name (INST-EA (D 3)))
	   ,@(invoke-interface-jsr code)))))

(define-rule statement
  (INTERPRETER-CALL:DEFINE (? cont) (? environment) (? name) (? value))
  (QUALIFIER (and (interpreter-call-argument? environment)
		  (interpreter-call-argument? value)))
  cont					; ignored
  (assignment-call code:compiler-define environment name value))

(define-rule statement
  (INTERPRETER-CALL:SET! (? cont) (? environment) (? name) (? value))
  (QUALIFIER (and (interpreter-call-argument? environment)
		  (interpreter-call-argument? value)))
  cont					; ignored
  (assignment-call code:compiler-set! environment name value))

(define (assignment-call code environment name value)
  (let ((set-environment
	 (interpreter-call-argument->machine-register! environment d2)))
    (let ((set-value (interpreter-call-argument->machine-register! value d4)))
      (let ((clear-map (clear-map!)))
	(LAP ,@set-environment
	     ,@set-value
	     ,@clear-map
	     ,@(load-constant name (INST-EA (D 3)))
	     ,@(invoke-interface-jsr code))))))