(* * Copyright (c) 1997-1999 Massachusetts Institute of Technology * * 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 of the License, 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; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * *) (* $Id: ast.ml,v 1.7 1999/02/19 17:22:08 athena Exp $ *) (* Here, we define a representation for a subset of C's abstract syntax tree (AST) and provide functions for manipulating it, unparsing it, and extracting information. *) let cvsid = "$Id: ast.ml,v 1.7 1999/02/19 17:22:08 athena Exp $" (*********************************** * Program structure ***********************************) type c_decl = Decl of string * expr type c_ast = Asch of Asched.annotated_schedule | Comment of string | For of c_ast * c_ast * c_ast * c_ast | Block of (c_decl list) * (c_ast list) | Binop of string * expr * expr | Expr_assign of expr * expr | Stmt_assign of expr * expr | Comma of c_ast * c_ast type c_fcn = Fcn of string * string * (c_decl list) * c_ast let unparse_decl = function Decl (a, b) -> a ^ " " ^ unparse_expr b ^ ";\n" let id = Comment ("Generated by " ^ cvsid) let foldr_string_concat l = fold_right (^) l "" let rec unparse_ast = function Asch a -> "{\n" ^ (unparse_annotated a) ^ "}\n" | Comment s -> " /* " ^ s ^ " */\n" | For (a, b, c, d) -> "for (" ^ unparse_ast a ^ "; " ^ unparse_ast b ^ "; " ^ unparse_ast c ^ ")" ^ unparse_ast d | Block (d, s) -> if (s == []) then "" else "{\n" ^ foldr_string_concat (map unparse_decl d) ^ foldr_string_concat (map unparse_ast s) ^ "}\n" | Binop (op, a, b) -> (unparse_expr a) ^ op ^ (unparse_expr b) | Expr_assign (a, b) -> (unparse_expr a) ^ " = " ^ (unparse_expr b) | Stmt_assign (a, b) -> (unparse_expr a) ^ " = " ^ (unparse_expr b) ^ ";\n" | Comma (a, b) -> (unparse_ast a) ^ ", " ^ (unparse_ast b) let unparse_function = function Fcn (typ, name, args, body) -> let rec unparse_args = function [Decl (a, b)] -> a ^ " " ^ unparse_expr b | (Decl (a, b)) :: s -> a ^ " " ^ unparse_expr b ^ ", " ^ unparse_args s | [] -> "" in (typ ^ " " ^ name ^ "(" ^ unparse_args args ^ ")\n" ^ unparse_ast body) (***************** Extracting Info from ASTs ***************) (* * traverse a a function and return a list of all expressions, * in the execution order *) let rec fcn_to_expr_list = let rec acode_to_expr_list = function AInstr (Assign (_, x)) -> [x] | ASeq (a, b) -> (asched_to_expr_list a) @ (asched_to_expr_list b) | _ -> [] and asched_to_expr_list (Annotate (_, _, _, _, code)) = acode_to_expr_list code and ast_to_expr_list = function Asch a -> asched_to_expr_list a | Block (_, a) -> flatten (map ast_to_expr_list a) | For (_, _, _, body) -> ast_to_expr_list body | _ -> [] in fun (Fcn (_, _, _, body)) -> ast_to_expr_list body (***************** Extracting Constants ***************) (* add a new key & value to a list of (key,value) pairs, where the keys are floats and each key is unique up to almost_equal *) let add_float_key_value list_so_far (k, v) = if exists (fun (k2, v2) -> almost_equal k k2) list_so_far then list_so_far else (k, v) :: list_so_far (* find all constants in a given expression *) let rec expr_to_constants = function | Real (a, e) -> [(a, e)] | Plus a -> flatten (map expr_to_constants a) | Times (a, b) -> (expr_to_constants a) @ (expr_to_constants b) | Uminus a -> expr_to_constants a | FunctionCall (_, a) -> expr_to_constants a | _ -> [] let extract_constants f = let constlist = flatten (map expr_to_constants (fcn_to_expr_list f)) in let unique_constants = fold_left add_float_key_value [] constlist in let unparsed_constants = foldr_string_concat (map (function (a, e) -> (konst_of_float a) ^ " = " ^ (string_of_float a) ^ " = \"" ^ (unparse_expr e) ^ "\"\n") unique_constants) in "/* List of constants required by this function: \n\n" ^ unparsed_constants ^ "\n*/\n" (***************** Extracting Operation Counts ***************) let count_stack_vars = let rec count_acode = function | ASeq (a, b) -> max (count_asched a) (count_asched b) | _ -> 0 and count_asched (Annotate (_, _, decl, _, code)) = (length decl) + (count_acode code) and count_ast = function | Asch a -> count_asched a | Block (d, a) -> (length d) + (max_list (map count_ast a)) | For (_, _, _, body) -> count_ast body | _ -> 0 in function (Fcn (_, _, _, body)) -> count_ast body let count_memory_acc f = let rec count_var_desc = function | Array _ -> 1 | Call (s, v) -> count_var_desc v | _ -> 0 and count_var (v, _) = count_var_desc v and count_acode = function | AInstr (Assign (v, _)) -> count_var v | ASeq (a, b) -> (count_asched a) + (count_asched b) | _ -> 0 and count_asched = function Annotate (_, _, _, _, code) -> count_acode code and count_ast = function | Asch a -> count_asched a | Block (_, a) -> (sum_list (map count_ast a)) | Comma (a, b) -> (count_ast a) + (count_ast b) | For (_, _, _, body) -> count_ast body | _ -> 0 and count_acc_expr_func acc = function | Var v -> acc + (count_var v) | Plus a -> fold_left count_acc_expr_func acc a | Times (a, b) -> fold_left count_acc_expr_func acc [a; b] | Uminus a -> count_acc_expr_func acc a | FunctionCall (_, a) -> count_acc_expr_func acc a | _ -> acc in let (Fcn (typ, name, args, body)) = f in (count_ast body) + fold_left count_acc_expr_func 0 (fcn_to_expr_list f) let rec count_flops_expr_func (adds, mults) = function | Plus [] -> (adds, mults) | Plus a -> let (newadds,newmults) = fold_left count_flops_expr_func (adds, mults) a in (newadds + (length a) - 1, newmults) | Times (a,b) -> let (newadds, newmults) = fold_left count_flops_expr_func (adds, mults) [a; b] in (newadds, newmults + 1) | Uminus a -> count_flops_expr_func (adds, mults) a | FunctionCall (f, a) -> count_flops_expr_func (adds, mults) a | _ -> (adds, mults) let count_flops f = fold_left count_flops_expr_func (0, 0) (fcn_to_expr_list f)