462 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			OCaml
		
	
	
	
	
	
			
		
		
	
	
			462 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			OCaml
		
	
	
	
	
	
| (*
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|  * Copyright (c) 1997-1999 Massachusetts Institute of Technology
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|  * Copyright (c) 2003, 2007-14 Matteo Frigo
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|  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation; either version 2 of the License, or
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|  * (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
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|  *
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|  *)
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| 
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| (*
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|  * This module contains the definition of a C-like abstract
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|  * syntax tree, and functions to convert ML values into C
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|  * programs
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|  *)
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| 
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| open Expr
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| open Annotate
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| open List
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| 
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| let realtype = "R"
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| let realtypep = realtype ^ " *"
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| let extended_realtype = "E"
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| let constrealtype = "const " ^ realtype
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| let constrealtypep = constrealtype ^ " *"
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| 
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| let stridetype = "stride"
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| 
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| (***********************************
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|  * C program structure 
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|  ***********************************)
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| type c_decl = 
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|   | Decl of string * string
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|   | Tdecl of string                (* arbitrary text declaration *)
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| 
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| and c_ast =
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|   | Asch of annotated_schedule
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|   | Simd_leavefun
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|   | Return of c_ast
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|   | For of c_ast * c_ast * c_ast * c_ast
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|   | If of c_ast * c_ast
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|   | Block of (c_decl list) * (c_ast list)
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|   | Binop of string * c_ast * c_ast
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|   | Expr_assign of c_ast * c_ast
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|   | Stmt_assign of c_ast * c_ast
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|   | Comma of c_ast * c_ast
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|   | Integer of int
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|   | CVar of string
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|   | CCall of string * c_ast
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|   | CPlus of c_ast list
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|   | ITimes of c_ast * c_ast
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|   | CUminus of c_ast
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| and c_fcn = Fcn of string * string * (c_decl list) * c_ast
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| 
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| 
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| let ctimes = function
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|   | (Integer 1), a -> a
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|   | a, (Integer 1) -> a
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|   | a, b -> ITimes (a, b)
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| 
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| (*
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|  * C AST unparser 
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|  *)
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| let foldr_string_concat l = fold_right (^) l ""
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| 
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| let rec unparse_expr_c =
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|   let yes x = x and no x = "" in
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| 
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|   let rec unparse_plus maybe = 
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|     let maybep = maybe " + " in
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|     function
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|     | [] -> ""
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|     | (Uminus (Times (a, b))) :: (Uminus c) :: d -> 
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| 	maybep ^ (op "FNMA" a b c) ^ (unparse_plus yes d)
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|     | (Uminus c) :: (Uminus (Times (a, b))) :: d -> 
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| 	maybep ^ (op "FNMA" a b c) ^ (unparse_plus yes d)
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|     | (Uminus (Times (a, b))) :: c :: d -> 
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| 	maybep ^ (op "FNMS" a b c) ^ (unparse_plus yes d)
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|     | c :: (Uminus (Times (a, b))) :: d -> 
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| 	maybep ^ (op "FNMS" a b c) ^ (unparse_plus yes d)
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|     | (Times (a, b)) :: (Uminus c) :: d -> 
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| 	maybep ^ (op "FMS" a b c) ^ (unparse_plus yes d)
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|     | (Uminus c) :: (Times (a, b)) :: d -> 
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| 	maybep ^ (op "FMS" a b c) ^ (unparse_plus yes d)
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|     | (Times (a, b)) :: c :: d -> 
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| 	maybep ^ (op "FMA" a b c) ^ (unparse_plus yes d)
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|     | c :: (Times (a, b)) :: d -> 
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| 	maybep ^ (op "FMA" a b c) ^ (unparse_plus yes d)
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|     | (Uminus a :: b) -> 
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| 	" - " ^ (parenthesize a) ^ (unparse_plus yes b)
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|     | (a :: b) -> 
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| 	maybep ^ (parenthesize a) ^ (unparse_plus yes b)
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|   and parenthesize x = match x with
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|   | (Load _) -> unparse_expr_c x
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|   | (Num _) -> unparse_expr_c x
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|   | _ -> "(" ^ (unparse_expr_c x) ^ ")"
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|   and op nam a b c =
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|     nam ^ "(" ^ (unparse_expr_c a) ^ ", " ^ (unparse_expr_c b) ^ ", " ^
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|     (unparse_expr_c c) ^ ")"
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|       			      
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|   in function
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|     | Load v -> Variable.unparse v
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|     | Num n -> Number.to_konst n
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|     | Plus [] -> "0.0 /* bug */"
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|     | Plus [a] -> " /* bug */ " ^ (unparse_expr_c a)
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|     | Plus a -> (unparse_plus no a)
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|     | Times (a, b) -> (parenthesize a) ^ " * " ^ (parenthesize b)
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|     | Uminus (Plus [a; Uminus b]) -> unparse_plus no [b; Uminus a]
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|     | Uminus a -> "- " ^ (parenthesize a)
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|     | _ -> failwith "unparse_expr_c"
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| 
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| and unparse_expr_generic = 
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|   let rec u x = unparse_expr_generic x
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|   and unary op a = Printf.sprintf "%s(%s)" op (u a)
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|   and binary op a b = Printf.sprintf "%s(%s, %s)" op (u a) (u b)
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|   and ternary op a b c = Printf.sprintf "%s(%s, %s, %s)" op (u a) (u b) (u c)
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|   and quaternary op a b c d = 
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|     Printf.sprintf "%s(%s, %s, %s, %s)" op (u a) (u b) (u c) (u d)
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|   and unparse_plus = function
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|     | [(Uminus (Times (a, b))); Times (c, d)] -> quaternary "FNMMS" a b c d
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|     | [Times (c, d); (Uminus (Times (a, b)))] -> quaternary "FNMMS" a b c d
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|     | [Times (c, d); (Times (a, b))] -> quaternary "FMMA" a b c d
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|     | [(Uminus (Times (a, b))); c] -> ternary "FNMS" a b c
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|     | [c; (Uminus (Times (a, b)))] -> ternary "FNMS" a b c
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|     | [(Uminus c); (Times (a, b))] -> ternary "FMS" a b c
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|     | [(Times (a, b)); (Uminus c)] -> ternary "FMS" a b c
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|     | [c; (Times (a, b))] -> ternary "FMA" a b c
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|     | [(Times (a, b)); c] -> ternary "FMA" a b c
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|     | [a; Uminus b] -> binary "SUB" a b
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|     | [a; b] -> binary "ADD" a b
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|     | a :: b :: c -> binary "ADD" a (Plus (b :: c))
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|     | _ -> failwith "unparse_plus"
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|   in function
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|     | Load v -> Variable.unparse v 
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|     | Num n -> Number.to_konst n
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|     | Plus a -> unparse_plus a
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|     | Times (a, b) -> binary "MUL" a b
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|     | Uminus a -> unary "NEG" a
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|     | _ -> failwith "unparse_expr"
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| 
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| and unparse_expr x = 
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|   if !Magic.generic_arith then
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|     unparse_expr_generic x
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|   else
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|     unparse_expr_c x
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| 
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| and unparse_assignment (Assign (v, x)) =
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|   (Variable.unparse v) ^ " = " ^ (unparse_expr x) ^ ";\n"
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| 
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| and unparse_annotated force_bracket = 
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|   let rec unparse_code = function
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|       ADone -> ""
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|     | AInstr i -> unparse_assignment i
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|     | ASeq (a, b) -> 
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|         (unparse_annotated false a) ^ (unparse_annotated false b)
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|   and declare_variables l = 
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|     let rec uvar = function
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| 	[] -> failwith "uvar"
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|       |	[v] -> (Variable.unparse v) ^ ";\n"
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|       | a :: b -> (Variable.unparse a) ^ ", " ^ (uvar b)
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|     in let rec vvar l = 
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|       let s = if !Magic.compact then 15 else 1 in
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|       if (List.length l <= s) then
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| 	match l with
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| 	  [] -> ""
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| 	| _ -> extended_realtype ^ " " ^ (uvar l)
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|       else
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| 	(vvar (Util.take s l)) ^ (vvar (Util.drop s l))
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|     in vvar (List.filter Variable.is_temporary l)
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|   in function
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|       Annotate (_, _, decl, _, code) ->
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|         if (not force_bracket) && (Util.null decl) then 
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|           unparse_code code
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|         else "{\n" ^
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|           (declare_variables decl) ^
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|           (unparse_code code) ^
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| 	  "}\n"
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| 
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| and unparse_decl = function
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|   | Decl (a, b) -> a ^ " " ^ b ^ ";\n"
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|   | Tdecl x -> x
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| 
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| and unparse_ast = 
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|   let rec unparse_plus = function
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|     | [] -> ""
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|     | (CUminus a :: b) -> " - " ^ (parenthesize a) ^ (unparse_plus b)
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|     | (a :: b) -> " + " ^ (parenthesize a) ^ (unparse_plus b)
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|   and parenthesize x = match x with
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|   | (CVar _) -> unparse_ast x
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|   | (CCall _) -> unparse_ast x
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|   | (Integer _) -> unparse_ast x
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|   | _ -> "(" ^ (unparse_ast x) ^ ")"
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| 
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|   in
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|   function
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|     | Asch a -> (unparse_annotated true a)
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|     | Simd_leavefun -> "" (* used only in SIMD code *)
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|     | Return x -> "return " ^ unparse_ast x ^ ";"
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|     | For (a, b, c, d) ->
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| 	"for (" ^
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| 	unparse_ast a ^ "; " ^ unparse_ast b ^ "; " ^ unparse_ast c
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| 	^ ")" ^ unparse_ast d
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|     | If (a, d) ->
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| 	"if (" ^
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| 	unparse_ast a 
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| 	^ ")" ^ unparse_ast d
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|     | Block (d, s) ->
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| 	if (s == []) then ""
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| 	else 
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|           "{\n"                                      ^ 
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|           foldr_string_concat (map unparse_decl d)   ^ 
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|           foldr_string_concat (map unparse_ast s)    ^
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|           "}\n"      
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|     | Binop (op, a, b) -> (unparse_ast a) ^ op ^ (unparse_ast b)
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|     | Expr_assign (a, b) -> (unparse_ast a) ^ " = " ^ (unparse_ast b)
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|     | Stmt_assign (a, b) -> (unparse_ast a) ^ " = " ^ (unparse_ast b) ^ ";\n"
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|     | Comma (a, b) -> (unparse_ast a) ^ ", " ^ (unparse_ast b)
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|     | Integer i -> string_of_int i
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|     | CVar s -> s
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|     | CCall (s, x) -> s ^ "(" ^ (unparse_ast x) ^ ")"
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|     | CPlus [] -> "0 /* bug */"
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|     | CPlus [a] -> " /* bug */ " ^ (unparse_ast a)
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|     | CPlus (a::b) -> (parenthesize a) ^ (unparse_plus b)
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|     | ITimes (a, b) -> (parenthesize a) ^ " * " ^ (parenthesize b)
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|     | CUminus a -> "- " ^ (parenthesize a)
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| 
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| and unparse_function = function
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|     Fcn (typ, name, args, body) ->
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|       let rec unparse_args = function
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|           [Decl (a, b)] -> a ^ " " ^ b 
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| 	| (Decl (a, b)) :: s -> a ^ " " ^ b  ^ ", "
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|             ^  unparse_args s
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| 	| [] -> ""
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| 	| _ -> failwith "unparse_function"
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|       in 
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|       (typ ^ " " ^ name ^ "(" ^ unparse_args args ^ ")\n" ^
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|        unparse_ast body)
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| 
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| 
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| (*************************************************************
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|  * traverse a a function and return a list of all expressions,
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|  * in the execution order
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|  **************************************************************)
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| let rec fcn_to_expr_list = fun (Fcn (_, _, _, body)) -> ast_to_expr_list body 
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| and acode_to_expr_list = function
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|     AInstr (Assign (_, x)) -> [x]
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|   | ASeq (a, b) -> 
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|       (asched_to_expr_list a) @ (asched_to_expr_list b)
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|   | _ -> []
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| and asched_to_expr_list (Annotate (_, _, _, _, code)) =
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|   acode_to_expr_list code
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| and ast_to_expr_list = function
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|     Asch a -> asched_to_expr_list a
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|   | Block (_, a) -> flatten (map ast_to_expr_list a)
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|   | For (_, _, _, body) ->  ast_to_expr_list body
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|   | If (_, body) ->  ast_to_expr_list body
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|   | _ -> []
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| 
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| (***********************
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|  * Extracting Constants
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|  ***********************)
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| 
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| (* add a new key & value to a list of (key,value) pairs, where
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|    the keys are floats and each key is unique up to almost_equal *)
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| 
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| let extract_constants f =
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|   let constlist = flatten (map expr_to_constants (ast_to_expr_list f))
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|   in map
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|        (fun n ->
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| 	  Tdecl 
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| 	    ("DK(" ^ (Number.to_konst n) ^ ", " ^ (Number.to_string n) ^ 
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| 	       ");\n"))
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|        (unique_constants constlist)
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|        
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| (******************************
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|    Extracting operation counts 
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|  ******************************)
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| 
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| let count_stack_vars =
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|   let rec count_acode = function
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|     | ASeq (a, b) -> max (count_asched a) (count_asched b)
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|     | _ -> 0
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|   and count_asched (Annotate (_, _, decl, _, code)) =
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|     (length decl) + (count_acode code)
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|   and count_ast = function
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|     | Asch a -> count_asched a
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|     | Block (d, a) -> (length d) + (Util.max_list (map count_ast a))
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|     | For (_, _, _, body) -> count_ast body
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|     | If (_, body) -> count_ast body
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|     | _ -> 0
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|   in function (Fcn (_, _, _, body)) -> count_ast body
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| 
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| let count_memory_acc f =
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|   let rec count_var v =
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|     if (Variable.is_locative v)	then 1 else 0
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|   and count_acode = function
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|     | AInstr (Assign (v, _)) -> count_var v
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|     | ASeq (a, b) -> (count_asched a) + (count_asched b)
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|     | _ -> 0
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|   and count_asched = function
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|       Annotate (_, _, _, _, code) -> count_acode code
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|   and count_ast = function
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|     | Asch a -> count_asched a
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|     | Block (_, a) -> (Util.sum_list (map count_ast a))
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|     | Comma (a, b) -> (count_ast a) + (count_ast b)
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|     | For (_, _, _, body) -> count_ast body
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|     | If (_, body) -> count_ast body
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|     | _ -> 0
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|   and count_acc_expr_func acc = function
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|     | Load v -> acc + (count_var v)
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|     | Plus a -> fold_left count_acc_expr_func acc a
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|     | Times (a, b) -> fold_left count_acc_expr_func acc [a; b]
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|     | Uminus a -> count_acc_expr_func acc a
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|     | _ -> acc
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|   in let (Fcn (typ, name, args, body)) = f
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|   in (count_ast body) + 
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|     fold_left count_acc_expr_func 0 (fcn_to_expr_list f)
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| 
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| let good_for_fma = To_alist.good_for_fma
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| 
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| let build_fma = function
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|   | [a; Times (b, c)] when good_for_fma (b, c) -> Some (a, b, c)
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|   | [Times (b, c); a] when good_for_fma (b, c) -> Some (a, b, c)
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|   | [a; Uminus (Times (b, c))] when good_for_fma (b, c) -> Some (a, b, c)
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|   | [Uminus (Times (b, c)); a] when good_for_fma (b, c) -> Some (a, b, c)
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|   | _ -> None
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| 
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| let rec count_flops_expr_func (adds, mults, fmas) = function
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|   | Plus [] -> (adds, mults, fmas)
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|   | Plus ([_; _] as a) -> 
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|       begin
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| 	match build_fma a with
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| 	  | None ->
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| 	      fold_left count_flops_expr_func 
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| 		(adds + (length a) - 1, mults, fmas) a
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| 	  | Some (a, b, c) ->
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| 	      fold_left count_flops_expr_func (adds, mults, fmas+1) [a; b; c]
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|       end
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|   | Plus (a :: b) -> 
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|       count_flops_expr_func (adds, mults, fmas) (Plus [a; Plus b])
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|   | Times (NaN MULTI_A,_)  -> (adds, mults, fmas)
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|   | Times (NaN MULTI_B,_)  -> (adds, mults, fmas)
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|   | Times (NaN I,b) -> count_flops_expr_func (adds, mults, fmas) b
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|   | Times (NaN CONJ,b) -> count_flops_expr_func (adds, mults, fmas) b
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|   | Times (a,b) -> fold_left count_flops_expr_func (adds, mults+1, fmas) [a; b]
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|   | CTimes (a,b) -> 
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|       fold_left count_flops_expr_func (adds+1, mults+2, fmas) [a; b]
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|   | CTimesJ (a,b) -> 
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|       fold_left count_flops_expr_func (adds+1, mults+2, fmas) [a; b]
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|   | Uminus a -> count_flops_expr_func (adds, mults, fmas) a
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|   | _ -> (adds, mults, fmas)
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| 
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| let count_flops f = 
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|     fold_left count_flops_expr_func (0, 0, 0) (fcn_to_expr_list f)
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| 
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| let count_constants f = 
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|     length (unique_constants (flatten (map expr_to_constants (fcn_to_expr_list f))))
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| 
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| let arith_complexity f =
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|   let (a, m, fmas) = count_flops f
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|   and v = count_stack_vars f
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|   and c = count_constants f
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|   and mem = count_memory_acc f
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|   in (a, m, fmas, v, c, mem)
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| 
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| (* print the operation costs *)
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| let print_cost f =
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|   let Fcn (_, _, _, _) = f 
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|   and (a, m, fmas, v, c, mem) = arith_complexity f
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|   in
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|   "/*\n"^
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|   " * This function contains " ^
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|   (string_of_int (a + fmas)) ^ " FP additions, "  ^
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|   (string_of_int (m + fmas)) ^ " FP multiplications,\n" ^
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|   " * (or, " ^
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|   (string_of_int a) ^ " additions, "  ^
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|   (string_of_int m) ^ " multiplications, " ^
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|   (string_of_int fmas) ^ " fused multiply/add),\n" ^
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|   " * " ^ (string_of_int v) ^ " stack variables, " ^
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|   (string_of_int c) ^ " constants, and " ^
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|   (string_of_int mem) ^ " memory accesses\n" ^
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|   " */\n"
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| 
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| (*****************************************
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|  * functions that create C arrays 
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|  *****************************************)
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| type stride = 
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|   | SVar of string
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|   | SConst of string
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|   | SInteger of int
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|   | SNeg of stride
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| 
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| type sstride =
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|   | Simple of int
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|   | Constant of (string * int)
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|   | Composite of (string * int)
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|   | Negative of sstride
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| 
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| let rec simplify_stride stride i =
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|     match (stride, i) with
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|       (_, 0) -> Simple 0
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|     | (SInteger n, i) -> Simple (n * i)
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|     | (SConst s, i) -> Constant (s, i)
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|     | (SVar s, i) -> Composite (s, i)
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|     | (SNeg x, i) -> 
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| 	match (simplify_stride x i) with
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| 	| Negative y -> y
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| 	| y -> Negative y
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|   
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| let rec cstride_to_string = function
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|   | Simple i -> string_of_int i
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|   | Constant (s, i) -> 
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|         if !Magic.lisp_syntax then
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| 	  "(* " ^ s ^ " " ^ (string_of_int i) ^ ")"
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| 	else
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| 	  s ^ " * " ^ (string_of_int i)
 | |
|   | Composite (s, i) -> 
 | |
|         if !Magic.lisp_syntax then
 | |
| 	  "(* " ^ s ^ " " ^ (string_of_int i) ^ ")"
 | |
| 	else
 | |
| 	  "WS(" ^ s ^ ", " ^ (string_of_int i) ^ ")"
 | |
|   | Negative x -> "-" ^ cstride_to_string x
 | |
| 
 | |
| let aref name index = 
 | |
|   if !Magic.lisp_syntax then
 | |
|     Printf.sprintf "(aref %s %s)"  name index
 | |
|   else
 | |
|     Printf.sprintf "%s[%s]"  name index
 | |
| 
 | |
| let array_subscript name stride k = 
 | |
|   aref name (cstride_to_string (simplify_stride stride k))
 | |
| 
 | |
| let varray_subscript name vstride stride v i = 
 | |
|   let vindex = simplify_stride vstride v
 | |
|   and iindex = simplify_stride stride i
 | |
|   in 
 | |
|   let index = 
 | |
|     match (vindex, iindex) with
 | |
|       (Simple vi, Simple ii) -> string_of_int (vi + ii)
 | |
|     | (Simple 0, x) -> cstride_to_string x
 | |
|     | (x, Simple 0) -> cstride_to_string x
 | |
|     | _ -> (cstride_to_string vindex) ^ " + " ^ (cstride_to_string iindex)
 | |
|   in aref name index
 | |
| 
 | |
| let real_of s = "c_re(" ^ s ^ ")"
 | |
| let imag_of s = "c_im(" ^ s ^ ")"
 | |
| 
 | |
| let flops_of f =
 | |
|   let (add, mul, fma) = count_flops f in
 | |
|   Printf.sprintf "{ %d, %d, %d, 0 }" add mul fma
 | 
