X-Git-Url: https://git.distorted.org.uk/~mdw/sod/blobdiff_plain/aa14a4cddcb96b681d5c19a2ec8bad382f43b264..1344e1f9c923a4d6602d64a33da175f48c7b7b64:/src/codegen-proto.lisp?ds=sidebyside diff --git a/src/codegen-proto.lisp b/src/codegen-proto.lisp index 24b8c38..571f0b0 100644 --- a/src/codegen-proto.lisp +++ b/src/codegen-proto.lisp @@ -38,17 +38,18 @@ (export 'var-in-use-p) (defgeneric var-in-use-p (var) (:documentation - "Answer whether VAR is currently being used. See WITH-TEMPORARY-VAR.") + "Answer whether VAR is currently being used. See `with-temporary-var'.") (:method (var) "Non-temporary variables are always in use." + (declare (ignore var)) t)) (defgeneric (setf var-in-use-p) (value var) (:documentation - "Record whether VAR is currently being used. See WITH-TEMPORARY-VAR.")) + "Record whether VAR is currently being used. See `with-temporary-var'.")) ;; Root class. -(export 'temporary-name) +(export '(temporary-name temp-tag)) (defclass temporary-name () ((tag :initarg :tag :reader temp-tag)) (:documentation @@ -61,10 +62,10 @@ This is automatically reset to zero before the output functions are invoked to write a file. This way, we can ensure that the same output - file is always produced from the same input." - ;; FIXME: this is currently a lie. Need some protocol to ensure that this - ;; happens. -) + file is always produced from the same input.") + +(define-clear-the-decks reset-codegen-index + (setf *temporary-index* 0)) ;; Important temporary names. @@ -73,6 +74,8 @@ (make-instance 'temporary-name :tag "sod__ap")) (defparameter *sod-master-ap* (make-instance 'temporary-name :tag "sod__master_ap")) +(defparameter *sod-tmp-ap* + (make-instance 'temporary-name :tag "sod__tmp_ap")) ;;;-------------------------------------------------------------------------- ;;; Instructions. @@ -85,12 +88,12 @@ "A base class for instructions. An `instruction' is anything which might be useful to string into a code - generator. Both statements and expressions map can be represented by - trees of instructions. The DEFINST macro is a convenient way of defining - new instructions. + generator. Both statements and expressions can be represented by trees of + instructions. The `definst' macro is a convenient way of defining new + instructions. The only important protocol for instructions is output, which is achieved - by calling PRINT-OBJECT with *PRINT-ESCAPE* nil. + by calling `print-object' with `*print-escape*' nil. This doesn't really do very much, but it acts as a handy marker for instruction subclasses.")) @@ -100,40 +103,51 @@ (:documentation "Returns a `metric' describing how complicated INST is. - The default metric of an inst node is simply 1; INST subclasses generated - by DEFINST (q.v.) have an automatically generated method which returns one - plus the sum of the metrics of the node's children. + The default metric of an inst node is simply 1; `inst' subclasses + generated by `definst' (q.v.) have an automatically generated method which + returns one plus the sum of the metrics of the node's children. This isn't intended to be a particularly rigorous definition. Its purpose is to allow code generators to make decisions about inlining or calling code fairly simply.") - (:method (inst) 1)) + (:method ((inst t)) + (declare (ignore inst)) + 1) + (:method ((inst null)) + (declare (ignore inst)) + 1) + (:method ((inst list)) + (reduce #'+ inst :key #'inst-metric))) ;; Instruction definition. (export 'definst) -(defmacro definst (code (streamvar) args &body body) +(defmacro definst (code (streamvar &key export) args &body body) "Define an instruction type and describe how to output it. - An INST can represent any structured piece of output syntax: a statement, - expression or declaration, for example. This macro defines the following - things: + An `inst' can represent any structured piece of output syntax: a + statement, expression or declaration, for example. This macro defines the + following things: - * A class CODE-INST to represent the instruction. + * A class `CODE-inst' to represent the instruction. * Instance slots named after the ARGS, with matching keyword initargs, - and INST-ARG readers. + and `inst-ARG' readers. - * A constructor MAKE-CODE-INST which accepts the ARGS (in order, not + * A constructor `make-CODE-inst' which accepts the ARGS (in order, not with keywords) as arguments and returns a fresh instance. - * A print method, which prints a diagnostic dump if *PRINT-ESCAPE* is + * A print method, which prints a diagnostic dump if `*print-escape*' is set, or invokes the BODY (with STREAMVAR bound to the output stream) otherwise. The BODY is expected to produce target code at this - point." + point. + + If EXPORT is non-nil, then export the `CODE-inst' and `make-CODE-inst' + symbols." (let ((inst-var (gensym "INST")) (class-name (symbolicate code '-inst)) + (constructor-name (symbolicate 'make- code '-inst)) (keys (mapcar (lambda (arg) (intern (symbol-name arg) :keyword)) args))) `(progn @@ -141,7 +155,7 @@ ,(mapcar (lambda (arg key) `(,arg :initarg ,key :reader ,(symbolicate 'inst- arg))) args keys)) - (defun ,(symbolicate 'make- code '-inst) (,@args) + (defun ,constructor-name (,@args) (make-instance ',class-name ,@(mappend #'list keys args))) (defmethod inst-metric ((,inst-var ,class-name)) (with-slots (,@args) ,inst-var @@ -152,30 +166,33 @@ (print-unreadable-object (,inst-var ,streamvar :type t) (format stream "~@<~@{~S ~@_~S~^ ~_~}~:>" ,@(mappend #'list keys args))) - (progn ,@body))))))) + (progn ,@body)))) + ,@(and export `((export '(,class-name ,constructor-name)))) + ',code))) ;; Important instruction classes. -(export '(block-inst make-block-inst var-inst make-var-inst - function-inst make-function-inst set-inst make-set-inst - return-inst make-return-inst expr-inst make-expr-inst - inst-decls inst-body inst-name inst-type inst-init inst-var - inst-expr)) - -(definst var (stream) (name type init) +(definst var (stream :export t) (name type init) (pprint-c-type type stream name) (when init - (format stream " = ~A" init))) -(definst set (stream) (var expr) + (format stream " = ~A" init)) + (write-char #\; stream)) +(definst set (stream :export t) (var expr) (format stream "~@<~A = ~@_~2I~A;~:>" var expr)) -(definst return (stream) (expr) +(definst update (stream :export t) (var op expr) + (format stream "~@<~A ~A= ~@_~2I~A;~:>" var op expr)) +(definst return (stream :export t) (expr) (format stream "return~@[ (~A)~];" expr)) -(definst expr (stream) (expr) +(definst break (stream :export t) () + (format stream "break;")) +(definst continue (stream :export t) () + (format stream "continue;")) +(definst expr (stream :export t) (expr) (format stream "~A;" expr)) -(definst block (stream) (decls body) - (format stream "{~:@_~@< ~2I~@[~{~A;~:@_~}~:@_~]~{~A~^~:@_~}~:>~:@_}" +(definst block (stream :export t) (decls body) + (format stream "{~:@_~@< ~2I~@[~{~A~:@_~}~:@_~]~{~A~^~:@_~}~:>~:@_}" decls body)) -(definst function (stream) (name type body) +(definst function (stream :export t) (name type body) (pprint-logical-block (stream nil) (princ "static " stream) (pprint-c-type type stream name) @@ -184,7 +201,7 @@ ;; Formatting utilities. (defun format-compound-statement* (stream child morep thunk) - "Underlying function for FORMAT-COMPOUND-STATEMENT." + "Underlying function for `format-compound-statement'." (cond ((typep child 'block-inst) (funcall thunk stream) (write-char #\space stream) @@ -211,7 +228,7 @@ "Format a compound statement to STREAM. The introductory material is printed by BODY. The CHILD is formatted - properly according to whether it's a BLOCK-INST. If MOREP is true, then + properly according to whether it's a `block-inst'. If MOREP is true, then allow for more stuff following the child." `(format-compound-statement* ,stream ,child ,morep (lambda (,stream) ,@body))) @@ -224,16 +241,16 @@ (export 'codegen-functions) (defgeneric codegen-functions (codegen) (:documentation - "Return the list of FUNCTION-INSTs of completed functions.")) + "Return the list of `function-inst's of completed functions.")) (export 'ensure-var) (defgeneric ensure-var (codegen name type &optional init) (:documentation "Add a variable to CODEGEN's list. - The variable is called NAME (which should be comparable using EQUAL and + The variable is called NAME (which should be comparable using `equal' and print to an identifier) and has the given TYPE. If INIT is present and - non-nil it is an expression INST used to provide the variable with an + non-nil it is an expression `inst' used to provide the variable with an initial value.")) (export '(emit-inst emit-insts)) @@ -246,6 +263,14 @@ (:method (codegen insts) (dolist (inst insts) (emit-inst codegen inst)))) +(export '(emit-decl emit-decls)) +(defgeneric emit-decl (codegen inst) + (:documentation + "Add INST to the end of CODEGEN's list of declarations.")) +(defgeneric emit-decls (codegen insts) + (:documentation + "Add a list of INSTS to the end of CODEGEN's list of declarations.")) + (export 'codegen-push) (defgeneric codegen-push (codegen) (:documentation @@ -267,7 +292,7 @@ "Adds a function to CODEGEN's list. Actually, we're not picky: FUNCTION can be any kind of object that you're - willing to find in the list returned by CODEGEN-FUNCTIONS.")) + willing to find in the list returned by `codegen-functions'.")) (export 'temporary-var) (defgeneric temporary-var (codegen type) @@ -276,8 +301,8 @@ The temporary variable will have the given TYPE, and will be marked in-use. You should clear the in-use flag explicitly when you've finished - with the variable -- or, better, use WITH-TEMPORARY-VAR to do the cleanup - automatically.")) + with the variable -- or, better, use `with-temporary-var' to do the + cleanup automatically.")) (export 'codegen-build-function) (defun codegen-build-function (codegen name type vars insts) @@ -292,7 +317,7 @@ (export 'codegen-pop-block) (defgeneric codegen-pop-block (codegen) (:documentation - "Makes a block (BLOCK-INST) out of the completed code in CODEGEN.") + "Makes a block (`block-inst') out of the completed code in CODEGEN.") (:method (codegen) (multiple-value-bind (vars insts) (codegen-pop codegen) (make-block-inst vars insts)))) @@ -313,7 +338,7 @@ "Evaluate BODY with VAR bound to a temporary variable name. During BODY, VAR will be marked in-use; when BODY ends, VAR will be marked - available for re-use." + available for re-use." `(let ((,var (temporary-var ,codegen ,type))) (unwind-protect (progn ,@body) @@ -328,22 +353,22 @@ The TARGET may be one of the following. - * :VOID, indicating that the value is to be discarded. The expression + * `:void', indicating that the value is to be discarded. The expression will still be evaluated. - * :VOID-RETURN, indicating that the value is to be discarded (as for - :VOID) and furthermore a `return' from the current function should be - forced after computing the value. + * `:void-return', indicating that the value is to be discarded (as for + `:void') and furthermore a `return' from the current function should + be forced after computing the value. - * :RETURN, indicating that the value is to be returned from the current - function. + * `:return', indicating that the value is to be returned from the + current function. * A variable name, indicating that the value is to be stored in the variable. - In the cases of :RETURN, :VOID and :VOID-RETURN targets, it is valid for - EXPR to be nil; this signifies that no computation needs to be performed. - Variable-name targets require an expression." + In the cases of `:return', `:void' and `:void-return' targets, it is valid + for EXPR to be nil; this signifies that no computation needs to be + performed. Variable-name targets require an expression." (case target (:return (emit-inst codegen (make-return-inst expr))) @@ -354,24 +379,24 @@ (export 'convert-stmts) (defun convert-stmts (codegen target type func) - "Invoke FUNC to deliver a value to a non-:RETURN target. + "Invoke FUNC to deliver a value to a non-`:return' target. - FUNC is a function which accepts a single argument, a non-:RETURN target, - and generates statements which deliver a value (see DELIVER-EXPR) of the - specified TYPE to this target. In general, the generated code will have - the form + FUNC is a function which accepts a single argument, a non-`:return' + target, and generates statements which deliver a value (see + `deliver-expr') of the specified TYPE to this target. In general, the + generated code will have the form setup instructions... - (DELIVER-EXPR CODEGEN TARGET (compute value...)) + (deliver-expr CODEGEN TARGET (compute value...)) cleanup instructions... where the cleanup instructions are essential to the proper working of the generated program. - CONVERT-STMTS will call FUNC to generate code, and arrange that its value - is correctly delivered to TARGET, regardless of what the TARGET is -- - i.e., it lifts the restriction to non-:RETURN targets. It does this by - inventing a new temporary variable." + The `convert-stmts' function will call FUNC to generate code, and arrange + that its value is correctly delivered to TARGET, regardless of what the + TARGET is -- i.e., it lifts the restriction to non-`:return' targets. It + does this by inventing a new temporary variable." (case target (:return (with-temporary-var (codegen var type)