c64-livecoding/wip-duuqnd/user-side-compiler/backend/code-generator.lisp

177 lines
6.9 KiB
Common Lisp

(in-package #:user-side-compiler)
(defclass asm-object ()
((%source :accessor source :initarg :source :initform nil)))
(defclass asm-label (asm-object)
((%name :accessor name :initarg :name)
(%address :accessor address :initform nil)))
(defclass asm-instruction (asm-object)
((%opcode :accessor opcode :initarg :opcode)
(%operand :accessor operand :initarg :operand :initform nil)
(%byte-length :accessor byte-length :initarg :byte-length)))
(defvar *asm-output* '())
(defun emit-asm-object (obj)
(check-type obj asm-object)
(setf *asm-output* (append *asm-output* (list obj))))
(defun emit-asm-instruction (&rest initargs)
(emit-asm-object (apply #'make-instance
'asm-instruction
initargs)))
(defun emit-asm-label (identity)
(emit-asm-object (make-instance 'asm-label :name identity)))
(defvar *variable-allocations* (make-hash-table))
(defvar *last-instruction* '(:nop))
(defun varvec-index-in-zeropage-p (index)
;; TODO: Handle case of too many variables
t)
(defun argvec-index-in-zeropage-p (index)
;; TODO: Handle case of too many arguments (? not realistically needed)
t)
(defparameter +argvec-offset+ #x00)
(defparameter +varvec-offset+ #x08)
(defmacro with-variable-allocations (allocations &body body)
`(let ((*variable-allocations* (make-hash-table)))
(loop :for alloc :in ,allocations
:do (setf (gethash (data alloc) *variable-allocations*) alloc))
,@body))
(defun allocation-details (data)
(gethash data *variable-allocations*))
(defun data-reference (data)
(ecase (strategy (allocation-details data))
((:named-variable :temporary-variable)
(+ (varvec-index (allocation-details data))
+varvec-offset+))
(:direct-to-argvec
(+ (position data (inputs (user data)))
+argvec-offset+))))
(defmacro define-normal-emitter (name immediate-opcode zeropage-opcode absolute-opcode)
`(defun ,name (mode value)
(cond ((eql mode :immediate)
(emit-asm-instruction :opcode ,immediate-opcode
:operand (the (unsigned-byte 8) value)
:byte-length 2))
((and (eql mode :address)
(< value #x100))
(emit-asm-instruction :opcode ,zeropage-opcode
:operand (the (unsigned-byte 8) value)
:byte-length 2))
((eql mode :address)
(emit-asm-instruction :opcode ,absolute-opcode
:operand (the (unsigned-byte 16) value)
:byte-length 3))
(t
(error "Invalid usage of ~A with arguments (~A ~A)" ',name mode value)))))
(define-normal-emitter emit-lda #xa9 #xa5 #xad)
(define-normal-emitter emit-sta (error "STA has no immediate mode.") #x85 #x8d)
(define-normal-emitter emit-adc #x69 #x65 #x6d)
(defun emit-store-result (result)
(if (or (null (allocation-details result))
(member (strategy (allocation-details result))
'(:constant :accumulator)))
(setf *last-instruction* '(:useless))
(progn
(emit-sta :address (data-reference result))
(setf *last-instruction* (list :store result)))))
(defun emit-load-data (data)
(if (or (member (strategy (allocation-details data))
'(:accumulator :direct-to-argvec))
(equal *last-instruction* (list :store data))
(equal *last-instruction* (list :load data)))
(setf *last-instruction* '(:useless))
(progn
(if (eql (strategy (allocation-details data)) :constant)
(emit-lda :immediate (ir-constant-value data))
(emit-lda :address (data-reference data)))
(setf *last-instruction* (list :load data)))))
(defmethod compile-ir ((inst ir-inst))
(warn "Skipped compiling ~A; no COMPILE-IR method" inst))
(defmethod compile-ir ((inst ir-plus))
(unless (= (length (inputs inst)) 2)
(error "During the final code generation step, IR-PLUS must have exactly 2 operands."))
(emit-load-data (first (inputs inst)))
(emit-asm-instruction :opcode #x18 :byte-length 1) ; Clear Carry
(if (eql (strategy (allocation-details (second (inputs inst))))
:constant)
(emit-adc :immediate (ir-constant-value (second (inputs inst))))
(emit-adc :address (data-reference (second (inputs inst)))))
(emit-store-result (output inst)))
(defmethod compile-ir ((inst ir-assign))
(emit-load-data (input inst))
(emit-store-result (output inst)))
(defmethod compile-ir ((inst ir-fetchvar))
(emit-load-data (input inst))
(emit-store-result (output inst)))
(defmethod compile-ir ((inst ir-call))
(loop :for arg :in (inputs inst)
:for arg-index :from 0
:do (emit-load-data arg)
:unless (eql (strategy (allocation-details arg)) :direct-to-argvec)
:do (emit-sta :address (+ arg-index +argvec-offset+)))
(emit-asm-instruction :opcode #x20 :operand (callee inst) :byte-length 1)
(emit-store-result (output inst)))
(defun link-assembly (assembly-list origin-address)
(let ((address origin-address))
(loop :for asm-obj :in assembly-list
:do (cond ((typep asm-obj 'asm-label)
(setf (address asm-obj) address))
((typep asm-obj 'asm-instruction)
(incf address (byte-length asm-obj)))))
;; TODO: Second pass, replacing labels with their addresses, both for
;; constant labels such as assembly routines and for generated labels.
(values assembly-list address)))
(defun quick-and-dirty-test-compile (text &key print-ir-p print-alloc-p make-asm-p)
(with-input-from-string (source-stream text)
(let ((*token-stream* (make-token-stream (tokenize source-stream))))
(let ((rb (with-compilation-setup (root-block builder)
(compile-node (match-syntax program) builder)
root-block)))
(do-iblocks (ib rb)
(optim-reorder-arguments ib)
(optim-direct-variable-use ib)
(optim-call-duplicate-args ib)
(optim-remove-unused ib))
(let ((allocations (allocate-values rb)))
(optim-reuse-temporary-slots rb allocations)
(when print-ir-p
(print-iblocks rb)
(terpri))
(when print-alloc-p
(loop :for allocation :in allocations
:do (format t "~%~A - ~A~{ - ~A~}"
(data allocation)
(strategy allocation)
(unless (null (varvec-index allocation))
(list (varvec-index allocation)))))
(terpri))
(when make-asm-p
(with-variable-allocations allocations
(let ((*asm-output* '()))
(do-iblocks (ib rb)
(emit-asm-label ib)
(do-instructions (inst ib)
(compile-ir inst)))
(link-assembly *asm-output* #x8000)))))))))