X-Git-Url: https://git.hcoop.net/bpt/guile.git/blobdiff_plain/b7742c6b7132544b9d6cd9cb32c09e2084ad9e52..51a1763f6596d594ebd774e7c3fd9138e6f4d507:/libguile/memoize.c diff --git a/libguile/memoize.c b/libguile/memoize.c dissimilarity index 78% index d37a72374..dfbeea781 100644 --- a/libguile/memoize.c +++ b/libguile/memoize.c @@ -1,1141 +1,918 @@ -/* Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009 - * Free Software Foundation, Inc. - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public License - * as published by the Free Software Foundation; either version 3 of - * the License, or (at your option) any later version. - * - * This library 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 - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - * 02110-1301 USA - */ - - - -#ifdef HAVE_CONFIG_H -# include -#endif - -#include - -#include "libguile/__scm.h" - -#include -#include "libguile/_scm.h" -#include "libguile/continuations.h" -#include "libguile/eq.h" -#include "libguile/list.h" -#include "libguile/macros.h" -#include "libguile/memoize.h" -#include "libguile/modules.h" -#include "libguile/srcprop.h" -#include "libguile/ports.h" -#include "libguile/print.h" -#include "libguile/strings.h" -#include "libguile/throw.h" -#include "libguile/validate.h" - - - - - -#if 0 -#define CAR(x) SCM_CAR(x) -#define CDR(x) SCM_CDR(x) -#define CAAR(x) SCM_CAAR(x) -#define CADR(x) SCM_CADR(x) -#define CDAR(x) SCM_CDAR(x) -#define CDDR(x) SCM_CDDR(x) -#define CADDR(x) SCM_CADDR(x) -#define CDDDR(x) SCM_CDDDR(x) -#define CADDDR(x) SCM_CDDDR(x) -#else -#define CAR(x) scm_car(x) -#define CDR(x) scm_cdr(x) -#define CAAR(x) scm_caar(x) -#define CADR(x) scm_cadr(x) -#define CDAR(x) scm_cdar(x) -#define CDDR(x) scm_cddr(x) -#define CADDR(x) scm_caddr(x) -#define CDDDR(x) scm_cdddr(x) -#define CADDDR(x) scm_cadddr(x) -#endif - - -static const char s_bad_expression[] = "Bad expression"; -static const char s_expression[] = "Missing or extra expression in"; -static const char s_missing_expression[] = "Missing expression in"; -static const char s_extra_expression[] = "Extra expression in"; -static const char s_empty_combination[] = "Illegal empty combination"; -static const char s_missing_body_expression[] = "Missing body expression in"; -static const char s_mixed_body_forms[] = "Mixed definitions and expressions in"; -static const char s_bad_define[] = "Bad define placement"; -static const char s_missing_clauses[] = "Missing clauses"; -static const char s_misplaced_else_clause[] = "Misplaced else clause"; -static const char s_bad_case_clause[] = "Bad case clause"; -static const char s_bad_case_labels[] = "Bad case labels"; -static const char s_duplicate_case_label[] = "Duplicate case label"; -static const char s_bad_cond_clause[] = "Bad cond clause"; -static const char s_missing_recipient[] = "Missing recipient in"; -static const char s_bad_variable[] = "Bad variable"; -static const char s_bad_bindings[] = "Bad bindings"; -static const char s_bad_binding[] = "Bad binding"; -static const char s_duplicate_binding[] = "Duplicate binding"; -static const char s_bad_exit_clause[] = "Bad exit clause"; -static const char s_bad_formals[] = "Bad formals"; -static const char s_bad_formal[] = "Bad formal"; -static const char s_duplicate_formal[] = "Duplicate formal"; -static const char s_splicing[] = "Non-list result for unquote-splicing"; -static const char s_bad_slot_number[] = "Bad slot number"; - - -/* Signal a syntax error. We distinguish between the form that caused the - * error and the enclosing expression. The error message will print out as - * shown in the following pattern. The file name and line number are only - * given when they can be determined from the erroneous form or from the - * enclosing expression. - * - * : In procedure memoization: - * : In file , line : in . */ - -SCM_SYMBOL (syntax_error_key, "syntax-error"); - -/* The prototype is needed to indicate that the function does not return. */ -static void -syntax_error (const char* const, const SCM, const SCM) SCM_NORETURN; - -static void -syntax_error (const char* const msg, const SCM form, const SCM expr) -{ - SCM msg_string = scm_from_locale_string (msg); - SCM filename = SCM_BOOL_F; - SCM linenr = SCM_BOOL_F; - const char *format; - SCM args; - - if (scm_is_pair (form)) - { - filename = scm_source_property (form, scm_sym_filename); - linenr = scm_source_property (form, scm_sym_line); - } - - if (scm_is_false (filename) && scm_is_false (linenr) && scm_is_pair (expr)) - { - filename = scm_source_property (expr, scm_sym_filename); - linenr = scm_source_property (expr, scm_sym_line); - } - - if (!SCM_UNBNDP (expr)) - { - if (scm_is_true (filename)) - { - format = "In file ~S, line ~S: ~A ~S in expression ~S."; - args = scm_list_5 (filename, linenr, msg_string, form, expr); - } - else if (scm_is_true (linenr)) - { - format = "In line ~S: ~A ~S in expression ~S."; - args = scm_list_4 (linenr, msg_string, form, expr); - } - else - { - format = "~A ~S in expression ~S."; - args = scm_list_3 (msg_string, form, expr); - } - } - else - { - if (scm_is_true (filename)) - { - format = "In file ~S, line ~S: ~A ~S."; - args = scm_list_4 (filename, linenr, msg_string, form); - } - else if (scm_is_true (linenr)) - { - format = "In line ~S: ~A ~S."; - args = scm_list_3 (linenr, msg_string, form); - } - else - { - format = "~A ~S."; - args = scm_list_2 (msg_string, form); - } - } - - scm_error (syntax_error_key, "memoization", format, args, SCM_BOOL_F); -} - - -/* Shortcut macros to simplify syntax error handling. */ -#define ASSERT_SYNTAX(cond, message, form) \ - { if (SCM_UNLIKELY (!(cond))) \ - syntax_error (message, form, SCM_UNDEFINED); } -#define ASSERT_SYNTAX_2(cond, message, form, expr) \ - { if (SCM_UNLIKELY (!(cond))) \ - syntax_error (message, form, expr); } - - - - -/* {Evaluator memoized expressions} - */ - -scm_t_bits scm_tc16_memoized; - -#define MAKMEMO(n, args) (scm_cell (scm_tc16_memoized | ((n) << 16), (scm_t_bits)(args))) - -#define MAKMEMO_BEGIN(exps) \ - MAKMEMO (SCM_M_BEGIN, exps) -#define MAKMEMO_IF(test, then, else_) \ - MAKMEMO (SCM_M_IF, scm_cons (test, scm_cons (then, else_))) -#define MAKMEMO_LAMBDA(nreq, rest, body) \ - MAKMEMO (SCM_M_LAMBDA, scm_cons (SCM_I_MAKINUM (nreq), scm_cons (rest, body))) -#define MAKMEMO_LET(inits, body) \ - MAKMEMO (SCM_M_LET, scm_cons (inits, body)) -#define MAKMEMO_QUOTE(exp) \ - MAKMEMO (SCM_M_QUOTE, exp) -#define MAKMEMO_DEFINE(var, val) \ - MAKMEMO (SCM_M_DEFINE, scm_cons (var, val)) -#define MAKMEMO_APPLY(exp) \ - MAKMEMO (SCM_M_APPLY, exp) -#define MAKMEMO_CONT(proc) \ - MAKMEMO (SCM_M_CONT, proc) -#define MAKMEMO_CALL_WITH_VALUES(prod, cons) \ - MAKMEMO (SCM_M_CALL_WITH_VALUES, scm_cons (prod, cons)) -#define MAKMEMO_CALL(proc, args) \ - MAKMEMO (SCM_M_CALL, scm_cons (proc, args)) -#define MAKMEMO_LEX_REF(n) \ - MAKMEMO (SCM_M_LEXICAL_REF, SCM_I_MAKINUM (n)) -#define MAKMEMO_LEX_SET(n, val) \ - MAKMEMO (SCM_M_LEXICAL_SET, scm_cons (SCM_I_MAKINUM (n), val)) -#define MAKMEMO_TOP_REF(var) \ - MAKMEMO (SCM_M_TOPLEVEL_REF, var) -#define MAKMEMO_TOP_SET(var, val) \ - MAKMEMO (SCM_M_TOPLEVEL_SET, scm_cons (var, val)) -#define MAKMEMO_MOD_REF(mod, var, public) \ - MAKMEMO (SCM_M_MODULE_REF, scm_cons (mod, scm_cons (var, public))) -#define MAKMEMO_MOD_SET(val, mod, var, public) \ - MAKMEMO (SCM_M_MODULE_SET, scm_cons (val, scm_cons (mod, scm_cons (var, public)))) - - - -/* This table must agree with the list of M_ constants in memoize.h */ -static const char *const memoized_tags[] = -{ - "begin", - "if", - "lambda", - "let", - "quote", - "define", - "apply", - "call-with-current-continuation", - "call-with-values", - "call", - "lexical-ref", - "lexical-set!", - "toplevel-ref", - "toplevel-set!", - "module-ref", - "module-set", -}; - -static int -scm_print_memoized (SCM memoized, SCM port, scm_print_state *pstate) -{ - scm_puts ("#", port); - return 1; -} - -static SCM scm_m_at (SCM xorig, SCM env); -static SCM scm_m_atat (SCM xorig, SCM env); -static SCM scm_m_and (SCM xorig, SCM env); -static SCM scm_m_apply (SCM xorig, SCM env); -static SCM scm_m_begin (SCM xorig, SCM env); -static SCM scm_m_cont (SCM xorig, SCM env); -static SCM scm_m_at_call_with_values (SCM xorig, SCM env); -static SCM scm_m_cond (SCM xorig, SCM env); -static SCM scm_m_define (SCM x, SCM env); -static SCM scm_m_eval_when (SCM xorig, SCM env); -static SCM scm_m_if (SCM xorig, SCM env); -static SCM scm_m_lambda (SCM xorig, SCM env); -static SCM scm_m_let (SCM xorig, SCM env); -static SCM scm_m_letrec (SCM xorig, SCM env); -static SCM scm_m_letstar (SCM xorig, SCM env); -static SCM scm_m_or (SCM xorig, SCM env); -static SCM scm_m_quote (SCM xorig, SCM env); -static SCM scm_m_set_x (SCM xorig, SCM env); - - - - - -typedef SCM (*t_syntax_transformer) (SCM, SCM); - -static t_syntax_transformer -memoize_env_ref_transformer (SCM env, SCM x) -{ - SCM var; - for (; scm_is_pair (env); env = CDR (env)) - if (scm_is_eq (x, CAR (env))) - return NULL; /* lexical */ - - var = scm_module_variable (env, x); - if (scm_is_true (var) && scm_is_true (scm_variable_bound_p (var)) - && SCM_MACROP (scm_variable_ref (var))) - { - SCM mac = scm_variable_ref (var); - if (SCM_IMP (SCM_MACRO_CODE (mac)) - || SCM_TYP7 (SCM_MACRO_CODE (mac)) != scm_tc7_subr_2) - syntax_error ("bad macro", x, SCM_UNDEFINED); - else - return (t_syntax_transformer)SCM_SUBRF (SCM_MACRO_CODE (mac)); /* global macro */ - } - else - return NULL; /* anything else */ -} - -static int -memoize_env_var_is_free (SCM env, SCM x) -{ - for (; scm_is_pair (env); env = CDR (env)) - if (scm_is_eq (x, CAR (env))) - return 0; /* bound */ - return 1; /* free */ -} - -static int -memoize_env_lexical_index (SCM env, SCM x) -{ - int i = 0; - for (; scm_is_pair (env); env = CDR (env), i++) - if (scm_is_eq (x, CAR (env))) - return i; /* bound */ - return -1; /* free */ -} - -static SCM -memoize_env_extend (SCM env, SCM vars) -{ - return scm_append (scm_list_2 (vars, env)); -} - -static SCM -memoize (SCM exp, SCM env) -{ - if (scm_is_pair (exp)) - { - SCM CAR; - t_syntax_transformer trans; - - CAR = CAR (exp); - if (scm_is_symbol (CAR)) - trans = memoize_env_ref_transformer (env, CAR); - else - trans = NULL; - - if (trans) - return trans (exp, env); - else - { - SCM args = SCM_EOL; - for (; scm_is_pair (exp); exp = CDR (exp)) - args = scm_cons (memoize (CAR (exp), env), args); - if (scm_is_null (exp)) - return MAKMEMO (SCM_M_CALL, scm_reverse_x (args, SCM_UNDEFINED)); - else - syntax_error ("expected a proper list", exp, SCM_UNDEFINED); - } - } - else if (scm_is_symbol (exp)) - { - int i = memoize_env_lexical_index (env, exp); - if (i < 0) - return MAKMEMO_TOP_REF (exp); - else - return MAKMEMO_LEX_REF (i); - } - else - return MAKMEMO_QUOTE (exp); -} - -static SCM -memoize_exprs (SCM forms, const SCM env) -{ - SCM ret = SCM_EOL; - - for (; !scm_is_null (forms); forms = CDR (forms)) - ret = scm_cons (memoize (CAR (forms), env), ret); - return scm_reverse_x (ret, SCM_UNDEFINED); -} - -static SCM -memoize_sequence (const SCM forms, const SCM env) -{ - ASSERT_SYNTAX (scm_ilength (forms) >= 1, s_bad_expression, - scm_cons (scm_sym_begin, forms)); - return MAKMEMO_BEGIN (memoize_exprs (forms, env)); -} - - - -/* Memoization. */ - -/* bimacros (built-in macros) have isym codes. - mmacros don't exist at runtime, they just expand out to more primitive - forms. */ -SCM_SYNTAX (s_at, "@", scm_i_makbimacro, scm_m_at); -SCM_SYNTAX (s_atat, "@@", scm_i_makbimacro, scm_m_atat); -SCM_SYNTAX (s_and, "and", scm_makmmacro, scm_m_and); -SCM_SYNTAX (s_begin, "begin", scm_i_makbimacro, scm_m_begin); -SCM_SYNTAX (s_atcall_cc, "@call-with-current-continuation", scm_i_makbimacro, scm_m_cont); -SCM_SYNTAX (s_at_call_with_values, "@call-with-values", scm_i_makbimacro, scm_m_at_call_with_values); -SCM_SYNTAX (s_cond, "cond", scm_makmmacro, scm_m_cond); -SCM_SYNTAX (s_define, "define", scm_i_makbimacro, scm_m_define); -SCM_SYNTAX (s_eval_when, "eval-when", scm_makmmacro, scm_m_eval_when); -SCM_SYNTAX (s_if, "if", scm_i_makbimacro, scm_m_if); -SCM_SYNTAX (s_lambda, "lambda", scm_i_makbimacro, scm_m_lambda); -SCM_SYNTAX (s_let, "let", scm_i_makbimacro, scm_m_let); -SCM_SYNTAX (s_letrec, "letrec", scm_makmmacro, scm_m_letrec); -SCM_SYNTAX (s_letstar, "let*", scm_makmmacro, scm_m_letstar); -SCM_SYNTAX (s_or, "or", scm_makmmacro, scm_m_or); -SCM_SYNTAX (s_quote, "quote", scm_i_makbimacro, scm_m_quote); -SCM_SYNTAX (s_set_x, "set!", scm_i_makbimacro, scm_m_set_x); -SCM_SYNTAX (s_atapply, "@apply", scm_i_makbimacro, scm_m_apply); - - -SCM_GLOBAL_SYMBOL (scm_sym_apply, "apply"); -SCM_GLOBAL_SYMBOL (scm_sym_arrow, "=>"); -SCM_GLOBAL_SYMBOL (scm_sym_at, "@"); -SCM_GLOBAL_SYMBOL (scm_sym_atat, "@@"); -SCM_GLOBAL_SYMBOL (scm_sym_at_call_with_values, "@call-with-values"); -SCM_GLOBAL_SYMBOL (scm_sym_atapply, "@apply"); -SCM_GLOBAL_SYMBOL (scm_sym_atcall_cc, "@call-with-current-continuation"); -SCM_GLOBAL_SYMBOL (scm_sym_begin, "begin"); -SCM_GLOBAL_SYMBOL (scm_sym_case, "case"); -SCM_GLOBAL_SYMBOL (scm_sym_cond, "cond"); -SCM_GLOBAL_SYMBOL (scm_sym_define, "define"); -SCM_GLOBAL_SYMBOL (scm_sym_else, "else"); -SCM_GLOBAL_SYMBOL (scm_sym_eval_when, "eval-when"); -SCM_GLOBAL_SYMBOL (scm_sym_if, "if"); -SCM_GLOBAL_SYMBOL (scm_sym_lambda, "lambda"); -SCM_GLOBAL_SYMBOL (scm_sym_let, "let"); -SCM_GLOBAL_SYMBOL (scm_sym_letrec, "letrec"); -SCM_GLOBAL_SYMBOL (scm_sym_letstar, "let*"); -SCM_GLOBAL_SYMBOL (scm_sym_or, "or"); -SCM_GLOBAL_SYMBOL (scm_sym_quote, "quote"); -SCM_GLOBAL_SYMBOL (scm_sym_set_x, "set!"); -SCM_SYMBOL (sym_eval, "eval"); -SCM_SYMBOL (sym_load, "load"); - -SCM_GLOBAL_SYMBOL (scm_sym_unquote, "unquote"); -SCM_GLOBAL_SYMBOL (scm_sym_quasiquote, "quasiquote"); -SCM_GLOBAL_SYMBOL (scm_sym_uq_splicing, "unquote-splicing"); - - -static SCM -scm_m_at (SCM expr, SCM env SCM_UNUSED) -{ - ASSERT_SYNTAX (scm_ilength (expr) == 3, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (CADR (expr)) > 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_is_symbol (CADDR (expr)), s_bad_expression, expr); - - return MAKMEMO_MOD_REF (CADR (expr), CADDR (expr), SCM_BOOL_T); -} - -static SCM -scm_m_atat (SCM expr, SCM env SCM_UNUSED) -{ - ASSERT_SYNTAX (scm_ilength (expr) == 3, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (CADR (expr)) > 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_is_symbol (CADDR (expr)), s_bad_expression, expr); - - return MAKMEMO_MOD_REF (CADR (expr), CADDR (expr), SCM_BOOL_F); -} - -static SCM -scm_m_and (SCM expr, SCM env) -{ - const SCM cdr_expr = CDR (expr); - - if (scm_is_null (cdr_expr)) - return MAKMEMO_QUOTE (SCM_BOOL_T); - ASSERT_SYNTAX (scm_is_pair (cdr_expr), s_bad_expression, expr); - - if (scm_is_null (CDR (cdr_expr))) - return memoize (CAR (cdr_expr), env); - else - return MAKMEMO_IF (memoize (CAR (cdr_expr), env), - scm_m_and (cdr_expr, env), - MAKMEMO_QUOTE (SCM_BOOL_F)); -} - -static SCM -scm_m_apply (SCM expr, SCM env) -{ - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_missing_expression, expr); - - return MAKMEMO_APPLY (memoize_exprs (cdr_expr, env)); -} - -static SCM -scm_m_begin (SCM expr, SCM env) -{ - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 1, s_bad_expression, expr); - return MAKMEMO_BEGIN (memoize_exprs (cdr_expr, env)); -} - -static SCM -scm_m_cont (SCM expr, SCM env) -{ - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); - - return MAKMEMO_CONT (memoize (CADR (expr), env)); -} - -static SCM -scm_m_at_call_with_values (SCM expr, SCM env) -{ - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); - - return MAKMEMO_CALL_WITH_VALUES (memoize (CADR (expr), env), - memoize (CADDR (expr), env)); -} - -static SCM -scm_m_cond (SCM expr, SCM env) -{ - /* Check, whether 'else or '=> is a literal, i. e. not bound to a value. */ - const int else_literal_p = memoize_env_var_is_free (env, scm_sym_else); - const int arrow_literal_p = memoize_env_var_is_free (env, scm_sym_arrow); - - const SCM clauses = CDR (expr); - SCM clause_idx; - SCM ret, loc; - - ASSERT_SYNTAX (scm_ilength (clauses) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (clauses) >= 1, s_missing_clauses, expr); - - ret = scm_cons (SCM_UNDEFINED, MAKMEMO_QUOTE (SCM_UNSPECIFIED)); - loc = ret; - - for (clause_idx = clauses; - !scm_is_null (clause_idx); - clause_idx = CDR (clause_idx)) - { - SCM test; - - const SCM clause = CAR (clause_idx); - const long length = scm_ilength (clause); - ASSERT_SYNTAX_2 (length >= 1, s_bad_cond_clause, clause, expr); - - test = CAR (clause); - if (scm_is_eq (test, scm_sym_else) && else_literal_p) - { - const int last_clause_p = scm_is_null (CDR (clause_idx)); - ASSERT_SYNTAX_2 (length >= 2, - s_bad_cond_clause, clause, expr); - ASSERT_SYNTAX_2 (last_clause_p, - s_misplaced_else_clause, clause, expr); - SCM_SETCDR (loc, - memoize (scm_cons (scm_sym_begin, CDR (clause)), env)); - } - else if (length >= 2 - && scm_is_eq (CADR (clause), scm_sym_arrow) - && arrow_literal_p) - { - SCM tmp = scm_gensym (scm_from_locale_string ("cond ")); - SCM i; - SCM new_env = scm_cons (tmp, env); - ASSERT_SYNTAX_2 (length > 2, s_missing_recipient, clause, expr); - ASSERT_SYNTAX_2 (length == 3, s_extra_expression, clause, expr); - i = MAKMEMO_IF (MAKMEMO_LEX_REF (0), - MAKMEMO_CALL (memoize (CADDR (clause), - scm_cons (tmp, new_env)), - scm_list_1 (MAKMEMO_LEX_REF (0))), - MAKMEMO_QUOTE (SCM_UNSPECIFIED)); - SCM_SETCDR (loc, - MAKMEMO_LET (scm_list_1 (memoize (CAR (clause), env)), - i)); - env = new_env; - loc = scm_last_pair (SCM_MEMOIZED_ARGS (i)); - } - /* FIXME length == 1 case */ - else - { - SCM i = MAKMEMO_IF (memoize (CAR (clause), env), - memoize (scm_cons (scm_sym_begin, CDR (clause)), env), - MAKMEMO_QUOTE (SCM_UNSPECIFIED)); - SCM_SETCDR (loc, i); - loc = scm_last_pair (SCM_MEMOIZED_ARGS (i)); - } - } - - return CDR (ret); -} - -/* According to Section 5.2.1 of R5RS we first have to make sure that the - variable is bound, and then perform the `(set! variable expression)' - operation. However, EXPRESSION _can_ be evaluated before VARIABLE is - bound. This means that EXPRESSION won't necessarily be able to assign - values to VARIABLE as in `(define foo (begin (set! foo 1) (+ foo 1)))'. */ -static SCM -scm_m_define (SCM expr, SCM env) -{ - const SCM cdr_expr = CDR (expr); - SCM body; - SCM variable; - - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); - ASSERT_SYNTAX (!scm_is_pair (env), s_bad_define, expr); - - body = CDR (cdr_expr); - variable = CAR (cdr_expr); - - if (scm_is_pair (variable)) - { - ASSERT_SYNTAX_2 (scm_is_symbol (CAR (variable)), s_bad_variable, variable, expr); - return MAKMEMO_DEFINE (CAR (variable), - memoize (scm_cons (scm_sym_lambda, - scm_cons (CDR (variable), body)), - env)); - } - ASSERT_SYNTAX_2 (scm_is_symbol (variable), s_bad_variable, variable, expr); - ASSERT_SYNTAX (scm_ilength (body) == 1, s_expression, expr); - return MAKMEMO_DEFINE (variable, memoize (CAR (body), env)); -} - -static SCM -scm_m_eval_when (SCM expr, SCM env) -{ - ASSERT_SYNTAX (scm_ilength (expr) >= 3, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (CADR (expr)) > 0, s_bad_expression, expr); - - if (scm_is_true (scm_memq (sym_eval, CADR (expr))) - || scm_is_true (scm_memq (sym_load, CADR (expr)))) - return MAKMEMO_BEGIN (memoize_exprs (CDDR (expr), env)); - else - return MAKMEMO_QUOTE (SCM_UNSPECIFIED); -} - -static SCM -scm_m_if (SCM expr, SCM env SCM_UNUSED) -{ - const SCM cdr_expr = CDR (expr); - const long length = scm_ilength (cdr_expr); - ASSERT_SYNTAX (length == 2 || length == 3, s_expression, expr); - return MAKMEMO_IF (memoize (CADR (expr), env), - memoize (CADDR (expr), env), - ((length == 3) - ? memoize (CADDDR (expr), env) - : MAKMEMO_QUOTE (SCM_UNSPECIFIED))); -} - -/* A helper function for memoize_lambda to support checking for duplicate - * formal arguments: Return true if OBJ is `eq?' to one of the elements of - * LIST or to the CDR of the last cons. Therefore, LIST may have any of the - * forms that a formal argument can have: - * , ( ...), ( ... . ) */ -static int -c_improper_memq (SCM obj, SCM list) -{ - for (; scm_is_pair (list); list = CDR (list)) - { - if (scm_is_eq (CAR (list), obj)) - return 1; - } - return scm_is_eq (list, obj); -} - -static SCM -scm_m_lambda (SCM expr, SCM env SCM_UNUSED) -{ - SCM formals; - SCM formals_idx; - SCM formal_vars = SCM_EOL; - int nreq = 0; - - const SCM cdr_expr = CDR (expr); - const long length = scm_ilength (cdr_expr); - ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (length >= 2, s_missing_expression, expr); - - /* Before iterating the list of formal arguments, make sure the formals - * actually are given as either a symbol or a non-cyclic list. */ - formals = CAR (cdr_expr); - if (scm_is_pair (formals)) - { - /* Dirk:FIXME:: We should check for a cyclic list of formals, and if - * detected, report a 'Bad formals' error. */ - } - else - { - ASSERT_SYNTAX_2 (scm_is_symbol (formals) || scm_is_null (formals), - s_bad_formals, formals, expr); - } - - /* Now iterate the list of formal arguments to check if all formals are - * symbols, and that there are no duplicates. */ - formals_idx = formals; - while (scm_is_pair (formals_idx)) - { - const SCM formal = CAR (formals_idx); - const SCM next_idx = CDR (formals_idx); - ASSERT_SYNTAX_2 (scm_is_symbol (formal), s_bad_formal, formal, expr); - ASSERT_SYNTAX_2 (!c_improper_memq (formal, next_idx), - s_duplicate_formal, formal, expr); - nreq++; - formal_vars = scm_cons (formal, formal_vars); - formals_idx = next_idx; - } - ASSERT_SYNTAX_2 (scm_is_null (formals_idx) || scm_is_symbol (formals_idx), - s_bad_formal, formals_idx, expr); - if (scm_is_symbol (formals_idx)) - formal_vars = scm_cons (formals_idx, formal_vars); - return MAKMEMO_LAMBDA (nreq, scm_symbol_p (formals_idx), - memoize_sequence (CDDR (expr), - memoize_env_extend (env, formal_vars))); -} - -/* Check if the format of the bindings is (( ) ...). */ -static void -check_bindings (const SCM bindings, const SCM expr) -{ - SCM binding_idx; - - ASSERT_SYNTAX_2 (scm_ilength (bindings) >= 0, - s_bad_bindings, bindings, expr); - - binding_idx = bindings; - for (; !scm_is_null (binding_idx); binding_idx = CDR (binding_idx)) - { - SCM name; /* const */ - - const SCM binding = CAR (binding_idx); - ASSERT_SYNTAX_2 (scm_ilength (binding) == 2, - s_bad_binding, binding, expr); - - name = CAR (binding); - ASSERT_SYNTAX_2 (scm_is_symbol (name), s_bad_variable, name, expr); - } -} - -/* The bindings, which must have the format ((v1 i1) (v2 i2) ... (vn in)), are - * transformed to the lists (vn .. v2 v1) and (i1 i2 ... in). If a duplicate - * variable name is detected, an error is signalled. */ -static int -transform_bindings (const SCM bindings, const SCM expr, - SCM *const rvarptr, SCM *const initptr) -{ - SCM rvariables = SCM_EOL; - SCM rinits = SCM_EOL; - SCM binding_idx = bindings; - int n = 0; - for (; !scm_is_null (binding_idx); binding_idx = CDR (binding_idx)) - { - const SCM binding = CAR (binding_idx); - const SCM CDR_binding = CDR (binding); - const SCM name = CAR (binding); - ASSERT_SYNTAX_2 (scm_is_false (scm_c_memq (name, rvariables)), - s_duplicate_binding, name, expr); - rvariables = scm_cons (name, rvariables); - rinits = scm_cons (CAR (CDR_binding), rinits); - n++; - } - *rvarptr = rvariables; - *initptr = scm_reverse_x (rinits, SCM_UNDEFINED); - return n; -} - -/* This function is a helper function for memoize_let. It transforms - * (let name ((var init) ...) body ...) into - * ((letrec ((name (lambda (var ...) body ...))) name) init ...) - * and memoizes the expression. It is assumed that the caller has checked - * that name is a symbol and that there are bindings and a body. */ -static SCM -memoize_named_let (const SCM expr, SCM env) -{ - SCM rvariables; - SCM inits; - int nreq; - - const SCM cdr_expr = CDR (expr); - const SCM name = CAR (cdr_expr); - const SCM cddr_expr = CDR (cdr_expr); - const SCM bindings = CAR (cddr_expr); - check_bindings (bindings, expr); - - nreq = transform_bindings (bindings, expr, &rvariables, &inits); - - env = scm_cons (name, env); - return MAKMEMO_LET - (scm_list_1 (MAKMEMO_QUOTE (SCM_UNDEFINED)), - MAKMEMO_BEGIN - (scm_list_2 (MAKMEMO_LEX_SET - (0, - MAKMEMO_LAMBDA - (nreq, SCM_BOOL_F, - memoize_sequence (CDDDR (expr), - memoize_env_extend (env, rvariables)))), - MAKMEMO_CALL (MAKMEMO_LEX_REF (0), - memoize_exprs (inits, env))))); -} - -/* (let ((v1 i1) (v2 i2) ...) body) with variables v1 .. vn and initializers - * i1 .. in is transformed to (#@let (vn ... v2 v1) (i1 i2 ...) body). */ -static SCM -scm_m_let (SCM expr, SCM env) -{ - SCM bindings; - - const SCM cdr_expr = CDR (expr); - const long length = scm_ilength (cdr_expr); - ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (length >= 2, s_missing_expression, expr); - - bindings = CAR (cdr_expr); - if (scm_is_symbol (bindings)) - { - ASSERT_SYNTAX (length >= 3, s_missing_expression, expr); - return memoize_named_let (expr, env); - } - - check_bindings (bindings, expr); - if (scm_is_null (bindings)) - return memoize_sequence (CDDR (expr), env); - else - { - SCM rvariables; - SCM inits; - transform_bindings (bindings, expr, &rvariables, &inits); - return MAKMEMO_LET (memoize_exprs (inits, env), - memoize_sequence (CDDR (expr), - memoize_env_extend (env, rvariables))); - } -} - -static SCM -scm_m_letrec (SCM expr, SCM env) -{ - SCM bindings; - - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); - - bindings = CAR (cdr_expr); - if (scm_is_null (bindings)) - return memoize_sequence (CDDR (expr), env); - else - { - SCM rvariables; - SCM inits; - SCM v, i; - SCM undefs = SCM_EOL; - SCM vals = SCM_EOL; - SCM sets = SCM_EOL; - SCM new_env; - int offset; - int n = transform_bindings (bindings, expr, &rvariables, &inits); - offset = n; - new_env = memoize_env_extend (env, rvariables); - for (v = scm_reverse (rvariables), i = inits; scm_is_pair (v); - v = CDR (v), i = CDR (i), n--) - { - undefs = scm_cons (MAKMEMO_QUOTE (SCM_UNDEFINED), undefs); - vals = scm_cons (memoize (CAR (i), new_env), vals); - sets = scm_cons (MAKMEMO_LEX_SET ((n-1) + offset, - MAKMEMO_LEX_REF (n-1)), - sets); - } - return MAKMEMO_LET - (undefs, - MAKMEMO_BEGIN (scm_list_2 (MAKMEMO_LET (scm_reverse (vals), - MAKMEMO_BEGIN (sets)), - memoize_sequence (CDDR (expr), - new_env)))); - } -} - -static SCM -scm_m_letstar (SCM expr, SCM env SCM_UNUSED) -{ - SCM bindings; - - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); - - bindings = CAR (cdr_expr); - if (scm_is_null (bindings)) - return memoize_sequence (CDDR (expr), env); - else - { - SCM rvariables; - SCM variables; - SCM inits; - SCM ret, loc; - transform_bindings (bindings, expr, &rvariables, &inits); - variables = scm_reverse (rvariables); - ret = scm_cons (SCM_UNDEFINED, SCM_UNSPECIFIED); - loc = ret; - for (; scm_is_pair (variables); - variables = CDR (variables), inits = CDR (inits)) - { SCM x = MAKMEMO_LET (scm_list_1 (memoize (CAR (inits), env)), - MAKMEMO_QUOTE (SCM_UNSPECIFIED)); - SCM_SETCDR (loc, x); - loc = scm_last_pair (SCM_MEMOIZED_ARGS (x)); - env = scm_cons (CAR (variables), env); - } - SCM_SETCDR (loc, memoize_sequence (CDDR (expr), env)); - return CDR (ret); - } -} - -static SCM -scm_m_or (SCM expr, SCM env SCM_UNUSED) -{ - SCM tail = CDR (expr); - SCM ret, loc; - const long length = scm_ilength (tail); - - ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); - - ret = scm_cons (SCM_UNDEFINED, SCM_UNSPECIFIED); - loc = ret; - for (; scm_is_pair (tail); tail = CDR (tail)) - { - SCM tmp = scm_gensym (scm_from_locale_string ("cond ")); - SCM x = MAKMEMO_IF (MAKMEMO_LEX_REF (0), - MAKMEMO_LEX_REF (0), - MAKMEMO_QUOTE (SCM_UNSPECIFIED)); - SCM new_env = scm_cons (tmp, env); - SCM_SETCDR (loc, MAKMEMO_LET (scm_list_1 (memoize (CAR (tail), - env)), - x)); - env = new_env; - loc = scm_last_pair (SCM_MEMOIZED_ARGS (x)); - } - SCM_SETCDR (loc, MAKMEMO_QUOTE (SCM_BOOL_F)); - return CDR (ret); -} - -static SCM -scm_m_quote (SCM expr, SCM env SCM_UNUSED) -{ - SCM quotee; - - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); - quotee = CAR (cdr_expr); - return MAKMEMO_QUOTE (quotee); -} - -static SCM -scm_m_set_x (SCM expr, SCM env) -{ - SCM variable; - SCM vmem; - - const SCM cdr_expr = CDR (expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); - ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); - variable = CAR (cdr_expr); - vmem = memoize (variable, env); - - switch (SCM_MEMOIZED_TAG (vmem)) - { - case SCM_M_LEXICAL_REF: - return MAKMEMO_LEX_SET (SCM_I_INUM (SCM_MEMOIZED_ARGS (vmem)), - memoize (CADDR (expr), env)); - case SCM_M_TOPLEVEL_REF: - return MAKMEMO_TOP_SET (variable, - memoize (CADDR (expr), env)); - case SCM_M_MODULE_REF: - return MAKMEMO_MOD_SET (memoize (CADDR (expr), env), - CAR (SCM_MEMOIZED_ARGS (vmem)), - CADR (SCM_MEMOIZED_ARGS (vmem)), - CDDR (SCM_MEMOIZED_ARGS (vmem))); - default: - syntax_error (s_bad_variable, variable, expr); - } -} - - - - -SCM_DEFINE (scm_memoize_expression, "memoize-expression", 1, 0, 0, - (SCM exp), - "Memoize the expression @var{exp}.") -#define FUNC_NAME s_scm_memoize_expression -{ - return memoize (exp, scm_current_module ()); -} -#undef FUNC_NAME - - - - -SCM_SYMBOL (sym_placeholder, "_"); - -static SCM unmemoize (SCM expr); - -static SCM -unmemoize_exprs (SCM exprs) -{ - SCM ret, tail; - if (scm_is_null (exprs)) - return SCM_EOL; - ret = scm_list_1 (unmemoize (CAR (exprs))); - tail = ret; - for (exprs = CDR (exprs); !scm_is_null (exprs); exprs = CDR (exprs)) - { - SCM_SETCDR (tail, scm_list_1 (unmemoize (CAR (exprs)))); - tail = CDR (tail); - } - return ret; -} - -static SCM -unmemoize_bindings (SCM inits) -{ - SCM ret, tail; - if (scm_is_null (inits)) - return SCM_EOL; - ret = scm_list_1 (scm_list_2 (sym_placeholder, unmemoize (CAR (inits)))); - tail = ret; - for (inits = CDR (inits); !scm_is_null (inits); inits = CDR (inits)) - { - SCM_SETCDR (tail, scm_list_1 (scm_list_2 (sym_placeholder, - unmemoize (CAR (inits))))); - tail = CDR (tail); - } - return ret; -} - -static SCM -unmemoize_lexical (SCM n) -{ - char buf[16]; - buf[15] = 0; - snprintf (buf, 15, "<%u>", scm_to_uint32 (n)); - return scm_from_locale_symbol (buf); -} - -static SCM -unmemoize (const SCM expr) -{ - SCM args; - - if (!SCM_MEMOIZED_P (expr)) - abort (); - - args = SCM_MEMOIZED_ARGS (expr); - switch (SCM_MEMOIZED_TAG (expr)) - { - case SCM_M_APPLY: - return scm_cons (scm_sym_atapply, unmemoize_exprs (args)); - case SCM_M_BEGIN: - return scm_cons (scm_sym_begin, unmemoize_exprs (args)); - case SCM_M_CALL: - return unmemoize_exprs (args); - case SCM_M_CONT: - return scm_list_2 (scm_sym_atcall_cc, unmemoize (args)); - case SCM_M_CALL_WITH_VALUES: - return scm_list_3 (scm_sym_at_call_with_values, - unmemoize (CAR (args)), unmemoize (CDR (args))); - case SCM_M_DEFINE: - return scm_list_3 (scm_sym_define, CAR (args), unmemoize (CDR (args))); - case SCM_M_IF: - return scm_list_4 (scm_sym_if, unmemoize (scm_car (args)), - unmemoize (scm_cadr (args)), unmemoize (scm_cddr (args))); - case SCM_M_LAMBDA: - return scm_list_3 (scm_sym_lambda, - scm_make_list (CAR (args), sym_placeholder), - unmemoize (CDDR (args))); - case SCM_M_LET: - return scm_list_3 (scm_sym_let, - unmemoize_bindings (CAR (args)), - unmemoize (CDR (args))); - case SCM_M_QUOTE: - return scm_list_2 (scm_sym_quote, args); - case SCM_M_LEXICAL_REF: - return unmemoize_lexical (args); - case SCM_M_LEXICAL_SET: - return scm_list_3 (scm_sym_set_x, unmemoize_lexical (CAR (args)), - unmemoize (CDR (args))); - case SCM_M_TOPLEVEL_REF: - return args; - case SCM_M_TOPLEVEL_SET: - return scm_list_3 (scm_sym_set_x, CAR (args), unmemoize (CDR (args))); - case SCM_M_MODULE_REF: - return scm_list_3 (scm_is_true (CDDR (args)) ? scm_sym_at : scm_sym_atat, - scm_i_finite_list_copy (CAR (args)), - CADR (args)); - case SCM_M_MODULE_SET: - return scm_list_3 (scm_sym_set_x, - scm_list_3 (scm_is_true (CDDDR (args)) - ? scm_sym_at : scm_sym_atat, - scm_i_finite_list_copy (CADR (args)), - CADDR (args)), - unmemoize (CAR (args))); - default: - abort (); - } -} - -SCM_DEFINE (scm_memoized_p, "memoized?", 1, 0, 0, - (SCM obj), - "Return @code{#t} if @var{obj} is memoized.") -#define FUNC_NAME s_scm_memoized_p -{ - return scm_from_bool (SCM_MEMOIZED_P (obj)); -} -#undef FUNC_NAME - -SCM_DEFINE (scm_unmemoize_expression, "unmemoize-expression", 1, 0, 0, - (SCM m), - "Unmemoize the memoized expression @var{m}.") -#define FUNC_NAME s_scm_unmemoize_expression -{ - SCM_VALIDATE_MEMOIZED (1, m); - return unmemoize (m); -} -#undef FUNC_NAME - - - - -void -scm_init_memoize () -{ - scm_tc16_memoized = scm_make_smob_type ("%memoized", 0); - scm_set_smob_mark (scm_tc16_memoized, scm_markcdr); - scm_set_smob_print (scm_tc16_memoized, scm_print_memoized); - -#include "libguile/memoize.x" -} - -/* - Local Variables: - c-file-style: "gnu" - End: -*/ +/* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, + * 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 + * Free Software Foundation, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public License + * as published by the Free Software Foundation; either version 3 of + * the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + + + +#ifdef HAVE_CONFIG_H +# include +#endif + +#include "libguile/__scm.h" +#include "libguile/_scm.h" +#include "libguile/continuations.h" +#include "libguile/eq.h" +#include "libguile/expand.h" +#include "libguile/list.h" +#include "libguile/macros.h" +#include "libguile/memoize.h" +#include "libguile/modules.h" +#include "libguile/srcprop.h" +#include "libguile/ports.h" +#include "libguile/print.h" +#include "libguile/strings.h" +#include "libguile/throw.h" +#include "libguile/validate.h" + + + + + +#define CAR(x) SCM_CAR(x) +#define CDR(x) SCM_CDR(x) +#define CAAR(x) SCM_CAAR(x) +#define CADR(x) SCM_CADR(x) +#define CDAR(x) SCM_CDAR(x) +#define CDDR(x) SCM_CDDR(x) +#define CADDR(x) SCM_CADDR(x) +#define CDDDR(x) SCM_CDDDR(x) +#define CADDDR(x) SCM_CADDDR(x) + + +SCM_SYMBOL (sym_case_lambda_star, "case-lambda*"); + + + + +/* {Evaluator memoized expressions} + */ + +scm_t_bits scm_tc16_memoized; + +#define MAKMEMO(n, args) \ + (scm_cell (scm_tc16_memoized | ((n) << 16), SCM_UNPACK (args))) + +#define MAKMEMO_BEGIN(exps) \ + MAKMEMO (SCM_M_BEGIN, exps) +#define MAKMEMO_IF(test, then, else_) \ + MAKMEMO (SCM_M_IF, scm_cons (test, scm_cons (then, else_))) +#define FIXED_ARITY(nreq) \ + scm_list_1 (SCM_I_MAKINUM (nreq)) +#define REST_ARITY(nreq, rest) \ + scm_list_2 (SCM_I_MAKINUM (nreq), rest) +#define FULL_ARITY(nreq, rest, nopt, kw, inits, alt) \ + scm_list_n (SCM_I_MAKINUM (nreq), rest, SCM_I_MAKINUM (nopt), kw, inits, \ + alt, SCM_UNDEFINED) +#define MAKMEMO_LAMBDA(body, arity, docstring) \ + MAKMEMO (SCM_M_LAMBDA, \ + scm_cons (body, scm_cons (docstring, arity))) +#define MAKMEMO_LET(inits, body) \ + MAKMEMO (SCM_M_LET, scm_cons (inits, body)) +#define MAKMEMO_QUOTE(exp) \ + MAKMEMO (SCM_M_QUOTE, exp) +#define MAKMEMO_DEFINE(var, val) \ + MAKMEMO (SCM_M_DEFINE, scm_cons (var, val)) +#define MAKMEMO_DYNWIND(in, expr, out) \ + MAKMEMO (SCM_M_DYNWIND, scm_cons (in, scm_cons (expr, out))) +#define MAKMEMO_WITH_FLUIDS(fluids, vals, expr) \ + MAKMEMO (SCM_M_WITH_FLUIDS, scm_cons (fluids, scm_cons (vals, expr))) +#define MAKMEMO_APPLY(proc, args)\ + MAKMEMO (SCM_M_APPLY, scm_list_2 (proc, args)) +#define MAKMEMO_CONT(proc) \ + MAKMEMO (SCM_M_CONT, proc) +#define MAKMEMO_CALL_WITH_VALUES(prod, cons) \ + MAKMEMO (SCM_M_CALL_WITH_VALUES, scm_cons (prod, cons)) +#define MAKMEMO_CALL(proc, nargs, args) \ + MAKMEMO (SCM_M_CALL, scm_cons (proc, scm_cons (SCM_I_MAKINUM (nargs), args))) +#define MAKMEMO_LEX_REF(n) \ + MAKMEMO (SCM_M_LEXICAL_REF, SCM_I_MAKINUM (n)) +#define MAKMEMO_LEX_SET(n, val) \ + MAKMEMO (SCM_M_LEXICAL_SET, scm_cons (SCM_I_MAKINUM (n), val)) +#define MAKMEMO_TOP_REF(var) \ + MAKMEMO (SCM_M_TOPLEVEL_REF, var) +#define MAKMEMO_TOP_SET(var, val) \ + MAKMEMO (SCM_M_TOPLEVEL_SET, scm_cons (var, val)) +#define MAKMEMO_MOD_REF(mod, var, public) \ + MAKMEMO (SCM_M_MODULE_REF, scm_cons (mod, scm_cons (var, public))) +#define MAKMEMO_MOD_SET(val, mod, var, public) \ + MAKMEMO (SCM_M_MODULE_SET, scm_cons (val, scm_cons (mod, scm_cons (var, public)))) +#define MAKMEMO_PROMPT(tag, exp, handler) \ + MAKMEMO (SCM_M_PROMPT, scm_cons (tag, scm_cons (exp, handler))) + + +/* Primitives for the evaluator */ +scm_t_bits scm_tc16_memoizer; +#define SCM_MEMOIZER_P(x) (SCM_SMOB_PREDICATE (scm_tc16_memoizer, (x))) +#define SCM_MEMOIZER(M) (SCM_SMOB_OBJECT_1 (M)) + + + +/* This table must agree with the list of M_ constants in memoize.h */ +static const char *const memoized_tags[] = +{ + "begin", + "if", + "lambda", + "let", + "quote", + "define", + "dynwind", + "with-fluids", + "apply", + "call/cc", + "call-with-values", + "call", + "lexical-ref", + "lexical-set!", + "toplevel-ref", + "toplevel-set!", + "module-ref", + "module-set!", + "prompt", +}; + +static int +scm_print_memoized (SCM memoized, SCM port, scm_print_state *pstate) +{ + scm_puts ("#", port); + return 1; +} + + + + + +static int +lookup (SCM x, SCM env) +{ + int i = 0; + for (; scm_is_pair (env); env = CDR (env), i++) + if (scm_is_eq (x, CAR (env))) + return i; /* bound */ + abort (); +} + + +/* Abbreviate SCM_EXPANDED_REF. Copied because I'm not sure about symbol pasting */ +#define REF(x,type,field) \ + (scm_struct_ref (x, SCM_I_MAKINUM (SCM_EXPANDED_##type##_##field))) + +static SCM list_of_guile = SCM_BOOL_F; + +static SCM memoize (SCM exp, SCM env); + +static SCM +memoize_exps (SCM exps, SCM env) +{ + SCM ret; + for (ret = SCM_EOL; scm_is_pair (exps); exps = CDR (exps)) + ret = scm_cons (memoize (CAR (exps), env), ret); + return scm_reverse_x (ret, SCM_UNDEFINED); +} + +static SCM +memoize (SCM exp, SCM env) +{ + if (!SCM_EXPANDED_P (exp)) + abort (); + + switch (SCM_EXPANDED_TYPE (exp)) + { + case SCM_EXPANDED_VOID: + return MAKMEMO_QUOTE (SCM_UNSPECIFIED); + + case SCM_EXPANDED_CONST: + return MAKMEMO_QUOTE (REF (exp, CONST, EXP)); + + case SCM_EXPANDED_PRIMITIVE_REF: + if (scm_is_eq (scm_current_module (), scm_the_root_module ())) + return MAKMEMO_TOP_REF (REF (exp, PRIMITIVE_REF, NAME)); + else + return MAKMEMO_MOD_REF (list_of_guile, REF (exp, PRIMITIVE_REF, NAME), + SCM_BOOL_F); + + case SCM_EXPANDED_LEXICAL_REF: + return MAKMEMO_LEX_REF (lookup (REF (exp, LEXICAL_REF, GENSYM), env)); + + case SCM_EXPANDED_LEXICAL_SET: + return MAKMEMO_LEX_SET (lookup (REF (exp, LEXICAL_SET, GENSYM), env), + memoize (REF (exp, LEXICAL_SET, EXP), env)); + + case SCM_EXPANDED_MODULE_REF: + return MAKMEMO_MOD_REF (REF (exp, MODULE_REF, MOD), + REF (exp, MODULE_REF, NAME), + REF (exp, MODULE_REF, PUBLIC)); + + case SCM_EXPANDED_MODULE_SET: + return MAKMEMO_MOD_SET (memoize (REF (exp, MODULE_SET, EXP), env), + REF (exp, MODULE_SET, MOD), + REF (exp, MODULE_SET, NAME), + REF (exp, MODULE_SET, PUBLIC)); + + case SCM_EXPANDED_TOPLEVEL_REF: + return MAKMEMO_TOP_REF (REF (exp, TOPLEVEL_REF, NAME)); + + case SCM_EXPANDED_TOPLEVEL_SET: + return MAKMEMO_TOP_SET (REF (exp, TOPLEVEL_SET, NAME), + memoize (REF (exp, TOPLEVEL_SET, EXP), env)); + + case SCM_EXPANDED_TOPLEVEL_DEFINE: + return MAKMEMO_DEFINE (REF (exp, TOPLEVEL_DEFINE, NAME), + memoize (REF (exp, TOPLEVEL_DEFINE, EXP), env)); + + case SCM_EXPANDED_CONDITIONAL: + return MAKMEMO_IF (memoize (REF (exp, CONDITIONAL, TEST), env), + memoize (REF (exp, CONDITIONAL, CONSEQUENT), env), + memoize (REF (exp, CONDITIONAL, ALTERNATE), env)); + + case SCM_EXPANDED_APPLICATION: + { + SCM proc, args; + + proc = REF (exp, APPLICATION, PROC); + args = memoize_exps (REF (exp, APPLICATION, ARGS), env); + + if (SCM_EXPANDED_TYPE (proc) == SCM_EXPANDED_TOPLEVEL_REF) + { + SCM var = scm_module_variable (scm_current_module (), + REF (proc, TOPLEVEL_REF, NAME)); + if (SCM_VARIABLEP (var)) + { + SCM val = SCM_VARIABLE_REF (var); + if (SCM_MEMOIZER_P (val)) + return scm_apply (SCM_SMOB_OBJECT_1 (val), args, SCM_EOL); + } + } + /* otherwise we all fall down here */ + return MAKMEMO_CALL (memoize (proc, env), scm_ilength (args), args); + } + + case SCM_EXPANDED_SEQUENCE: + return MAKMEMO_BEGIN (memoize_exps (REF (exp, SEQUENCE, EXPS), env)); + + case SCM_EXPANDED_LAMBDA: + /* The body will be a lambda-case or #f. */ + { + SCM meta, docstring, body, proc; + + meta = REF (exp, LAMBDA, META); + docstring = scm_assoc_ref (meta, scm_sym_documentation); + + body = REF (exp, LAMBDA, BODY); + if (scm_is_false (body)) + /* Give a body to case-lambda with no clauses. */ + proc = MAKMEMO_LAMBDA + (MAKMEMO_CALL + (MAKMEMO_MOD_REF (list_of_guile, + scm_from_latin1_symbol ("throw"), + SCM_BOOL_F), + 5, + scm_list_5 (MAKMEMO_QUOTE (scm_args_number_key), + MAKMEMO_QUOTE (SCM_BOOL_F), + MAKMEMO_QUOTE (scm_from_latin1_string + ("Wrong number of arguments")), + MAKMEMO_QUOTE (SCM_EOL), + MAKMEMO_QUOTE (SCM_BOOL_F))), + FIXED_ARITY (0), + SCM_BOOL_F /* docstring */); + else + proc = memoize (body, env); + + if (scm_is_string (docstring)) + { + SCM args = SCM_MEMOIZED_ARGS (proc); + SCM_SETCAR (SCM_CDR (args), docstring); + } + + return proc; + } + + case SCM_EXPANDED_LAMBDA_CASE: + { + SCM req, rest, opt, kw, inits, vars, body, alt; + SCM walk, minits, arity, new_env; + int nreq, nopt, ntotal; + + req = REF (exp, LAMBDA_CASE, REQ); + rest = scm_not (scm_not (REF (exp, LAMBDA_CASE, REST))); + opt = REF (exp, LAMBDA_CASE, OPT); + kw = REF (exp, LAMBDA_CASE, KW); + inits = REF (exp, LAMBDA_CASE, INITS); + vars = REF (exp, LAMBDA_CASE, GENSYMS); + body = REF (exp, LAMBDA_CASE, BODY); + alt = REF (exp, LAMBDA_CASE, ALTERNATE); + + nreq = scm_ilength (req); + nopt = scm_is_pair (opt) ? scm_ilength (opt) : 0; + ntotal = scm_ilength (vars); + + /* The vars are the gensyms, according to the divine plan. But we need + to memoize the inits within their appropriate environment, + complicating things. */ + new_env = env; + for (walk = req; scm_is_pair (walk); + walk = CDR (walk), vars = CDR (vars)) + new_env = scm_cons (CAR (vars), new_env); + + minits = SCM_EOL; + for (walk = opt; scm_is_pair (walk); + walk = CDR (walk), vars = CDR (vars), inits = CDR (inits)) + { + minits = scm_cons (memoize (CAR (inits), new_env), minits); + new_env = scm_cons (CAR (vars), new_env); + } + + if (scm_is_true (rest)) + { + new_env = scm_cons (CAR (vars), new_env); + vars = CDR (vars); + } + + for (; scm_is_pair (inits); vars = CDR (vars), inits = CDR (inits)) + { + minits = scm_cons (memoize (CAR (inits), new_env), minits); + new_env = scm_cons (CAR (vars), new_env); + } + if (!scm_is_null (vars)) + abort (); + + minits = scm_reverse_x (minits, SCM_UNDEFINED); + + if (scm_is_true (kw)) + { + /* (aok? (kw name sym) ...) -> (aok? (kw . index) ...) */ + SCM aok = CAR (kw), indices = SCM_EOL; + for (kw = CDR (kw); scm_is_pair (kw); kw = CDR (kw)) + { + SCM k; + int idx; + + k = CAR (CAR (kw)); + idx = ntotal - 1 - lookup (CADDR (CAR (kw)), new_env); + indices = scm_acons (k, SCM_I_MAKINUM (idx), indices); + } + kw = scm_cons (aok, scm_reverse_x (indices, SCM_UNDEFINED)); + } + + if (scm_is_false (alt) && scm_is_false (kw) && scm_is_false (opt)) + { + if (scm_is_false (rest)) + arity = FIXED_ARITY (nreq); + else + arity = REST_ARITY (nreq, SCM_BOOL_T); + } + else if (scm_is_true (alt)) + arity = FULL_ARITY (nreq, rest, nopt, kw, minits, + SCM_MEMOIZED_ARGS (memoize (alt, env))); + else + arity = FULL_ARITY (nreq, rest, nopt, kw, minits, SCM_BOOL_F); + + return MAKMEMO_LAMBDA (memoize (body, new_env), arity, + SCM_BOOL_F /* docstring */); + } + + case SCM_EXPANDED_LET: + { + SCM vars, exps, body, inits, new_env; + + vars = REF (exp, LET, GENSYMS); + exps = REF (exp, LET, VALS); + body = REF (exp, LET, BODY); + + inits = SCM_EOL; + new_env = env; + for (; scm_is_pair (vars); vars = CDR (vars), exps = CDR (exps)) + { + new_env = scm_cons (CAR (vars), new_env); + inits = scm_cons (memoize (CAR (exps), env), inits); + } + + return MAKMEMO_LET (scm_reverse_x (inits, SCM_UNDEFINED), + memoize (body, new_env)); + } + + case SCM_EXPANDED_LETREC: + { + SCM vars, exps, body, undefs, new_env; + int i, nvars, in_order_p; + + vars = REF (exp, LETREC, GENSYMS); + exps = REF (exp, LETREC, VALS); + body = REF (exp, LETREC, BODY); + in_order_p = scm_is_true (REF (exp, LETREC, IN_ORDER_P)); + nvars = i = scm_ilength (vars); + undefs = SCM_EOL; + new_env = env; + + for (; scm_is_pair (vars); vars = CDR (vars)) + { + new_env = scm_cons (CAR (vars), new_env); + undefs = scm_cons (MAKMEMO_QUOTE (SCM_UNDEFINED), undefs); + } + + if (in_order_p) + { + SCM body_exps = SCM_EOL; + for (; scm_is_pair (exps); exps = CDR (exps), i--) + body_exps = scm_cons (MAKMEMO_LEX_SET (i-1, + memoize (CAR (exps), new_env)), + body_exps); + body_exps = scm_cons (memoize (body, new_env), body_exps); + body_exps = scm_reverse_x (body_exps, SCM_UNDEFINED); + return MAKMEMO_LET (undefs, MAKMEMO_BEGIN (body_exps)); + } + else + { + SCM sets = SCM_EOL, inits = SCM_EOL; + for (; scm_is_pair (exps); exps = CDR (exps), i--) + { + sets = scm_cons (MAKMEMO_LEX_SET ((i-1) + nvars, + MAKMEMO_LEX_REF (i-1)), + sets); + inits = scm_cons (memoize (CAR (exps), new_env), inits); + } + inits = scm_reverse_x (inits, SCM_UNDEFINED); + return MAKMEMO_LET + (undefs, + MAKMEMO_BEGIN (scm_list_2 (MAKMEMO_LET (inits, MAKMEMO_BEGIN (sets)), + memoize (body, new_env)))); + } + } + + case SCM_EXPANDED_DYNLET: + return MAKMEMO_WITH_FLUIDS (memoize_exps (REF (exp, DYNLET, FLUIDS), env), + memoize_exps (REF (exp, DYNLET, VALS), env), + memoize (REF (exp, DYNLET, BODY), env)); + + default: + abort (); + } +} + + + + +SCM_DEFINE (scm_memoize_expression, "memoize-expression", 1, 0, 0, + (SCM exp), + "Memoize the expression @var{exp}.") +#define FUNC_NAME s_scm_memoize_expression +{ + SCM_ASSERT_TYPE (SCM_EXPANDED_P (exp), exp, 1, FUNC_NAME, "expanded"); + return memoize (exp, scm_current_module ()); +} +#undef FUNC_NAME + + + + +#define SCM_MAKE_MEMOIZER(STR, MEMOIZER, N) \ + (scm_cell (scm_tc16_memoizer, \ + SCM_UNPACK (scm_c_make_gsubr (STR, N, 0, 0, MEMOIZER)))) +#define SCM_DEFINE_MEMOIZER(STR, MEMOIZER, N) \ +SCM_SNARF_INIT(scm_c_define (STR, SCM_MAKE_MEMOIZER (STR, MEMOIZER, N))) + +#define SCM_MAKE_REST_MEMOIZER(STR, MEMOIZER, N) \ + (scm_cell (scm_tc16_memoizer, \ + SCM_UNPACK ((scm_c_make_gsubr (STR, N, 0, 1, MEMOIZER))))) +#define SCM_DEFINE_REST_MEMOIZER(STR, MEMOIZER, N) \ +SCM_SNARF_INIT(scm_c_define (STR, SCM_MAKE_REST_MEMOIZER (STR, MEMOIZER, N))) + +static SCM m_apply (SCM proc, SCM arg, SCM rest); +static SCM m_call_cc (SCM proc); +static SCM m_call_values (SCM prod, SCM cons); +static SCM m_dynamic_wind (SCM pre, SCM exp, SCM post); +static SCM m_prompt (SCM tag, SCM exp, SCM handler); + +SCM_DEFINE_REST_MEMOIZER ("@apply", m_apply, 2); +SCM_DEFINE_MEMOIZER ("@call-with-current-continuation", m_call_cc, 1); +SCM_DEFINE_MEMOIZER ("@call-with-values", m_call_values, 2); +SCM_DEFINE_MEMOIZER ("@dynamic-wind", m_dynamic_wind, 3); +SCM_DEFINE_MEMOIZER ("@prompt", m_prompt, 3); + + + + +static SCM m_apply (SCM proc, SCM arg, SCM rest) +#define FUNC_NAME "@apply" +{ + long len; + + SCM_VALIDATE_MEMOIZED (1, proc); + SCM_VALIDATE_MEMOIZED (2, arg); + len = scm_ilength (rest); + if (len < 0) + abort (); + else if (len == 0) + return MAKMEMO_APPLY (proc, arg); + else + { + SCM tail; + + rest = scm_reverse (rest); + tail = scm_car (rest); + rest = scm_cdr (rest); + len--; + + while (scm_is_pair (rest)) + { + tail = MAKMEMO_CALL (MAKMEMO_MOD_REF (scm_list_1 (scm_from_latin1_symbol ("guile")), + scm_from_latin1_symbol ("cons"), + SCM_BOOL_F), + 2, + scm_list_2 (scm_car (rest), tail)); + rest = scm_cdr (rest); + } + return MAKMEMO_APPLY (proc, tail); + } +} +#undef FUNC_NAME + +static SCM m_call_cc (SCM proc) +#define FUNC_NAME "@call-with-current-continuation" +{ + SCM_VALIDATE_MEMOIZED (1, proc); + return MAKMEMO_CONT (proc); +} +#undef FUNC_NAME + +static SCM m_call_values (SCM prod, SCM cons) +#define FUNC_NAME "@call-with-values" +{ + SCM_VALIDATE_MEMOIZED (1, prod); + SCM_VALIDATE_MEMOIZED (2, cons); + return MAKMEMO_CALL_WITH_VALUES (prod, cons); +} +#undef FUNC_NAME + +static SCM m_dynamic_wind (SCM in, SCM expr, SCM out) +#define FUNC_NAME "memoize-dynwind" +{ + SCM_VALIDATE_MEMOIZED (1, in); + SCM_VALIDATE_MEMOIZED (2, expr); + SCM_VALIDATE_MEMOIZED (3, out); + return MAKMEMO_DYNWIND (in, expr, out); +} +#undef FUNC_NAME + +static SCM m_prompt (SCM tag, SCM exp, SCM handler) +#define FUNC_NAME "@prompt" +{ + SCM_VALIDATE_MEMOIZED (1, tag); + SCM_VALIDATE_MEMOIZED (2, exp); + SCM_VALIDATE_MEMOIZED (3, handler); + return MAKMEMO_PROMPT (tag, exp, handler); +} +#undef FUNC_NAME + + + + +SCM_SYMBOL (sym_placeholder, "_"); + +static SCM unmemoize (SCM expr); + +static SCM +unmemoize_exprs (SCM exprs) +{ + SCM ret, tail; + if (scm_is_null (exprs)) + return SCM_EOL; + ret = scm_list_1 (unmemoize (CAR (exprs))); + tail = ret; + for (exprs = CDR (exprs); !scm_is_null (exprs); exprs = CDR (exprs)) + { + SCM_SETCDR (tail, scm_list_1 (unmemoize (CAR (exprs)))); + tail = CDR (tail); + } + return ret; +} + +static SCM +unmemoize_bindings (SCM inits) +{ + SCM ret, tail; + if (scm_is_null (inits)) + return SCM_EOL; + ret = scm_list_1 (scm_list_2 (sym_placeholder, unmemoize (CAR (inits)))); + tail = ret; + for (inits = CDR (inits); !scm_is_null (inits); inits = CDR (inits)) + { + SCM_SETCDR (tail, scm_list_1 (scm_list_2 (sym_placeholder, + unmemoize (CAR (inits))))); + tail = CDR (tail); + } + return ret; +} + +static SCM +unmemoize_lexical (SCM n) +{ + char buf[16]; + buf[15] = 0; + snprintf (buf, 15, "<%u>", scm_to_uint32 (n)); + return scm_from_locale_symbol (buf); +} + +static SCM +unmemoize (const SCM expr) +{ + SCM args; + + if (!SCM_MEMOIZED_P (expr)) + abort (); + + args = SCM_MEMOIZED_ARGS (expr); + switch (SCM_MEMOIZED_TAG (expr)) + { + case SCM_M_APPLY: + return scm_cons (scm_sym_atapply, unmemoize_exprs (args)); + case SCM_M_BEGIN: + return scm_cons (scm_sym_begin, unmemoize_exprs (args)); + case SCM_M_CALL: + return scm_cons (unmemoize (CAR (args)), unmemoize_exprs (CDDR (args))); + case SCM_M_CONT: + return scm_list_2 (scm_sym_atcall_cc, unmemoize (args)); + case SCM_M_CALL_WITH_VALUES: + return scm_list_3 (scm_sym_at_call_with_values, + unmemoize (CAR (args)), unmemoize (CDR (args))); + case SCM_M_DEFINE: + return scm_list_3 (scm_sym_define, CAR (args), unmemoize (CDR (args))); + case SCM_M_DYNWIND: + return scm_list_4 (scm_sym_at_dynamic_wind, + unmemoize (CAR (args)), + unmemoize (CADR (args)), + unmemoize (CDDR (args))); + case SCM_M_WITH_FLUIDS: + { + SCM binds = SCM_EOL, fluids, vals; + for (fluids = CAR (args), vals = CADR (args); scm_is_pair (fluids); + fluids = CDR (fluids), vals = CDR (vals)) + binds = scm_cons (scm_list_2 (unmemoize (CAR (fluids)), + unmemoize (CAR (vals))), + binds); + return scm_list_3 (scm_sym_with_fluids, + scm_reverse_x (binds, SCM_UNDEFINED), + unmemoize (CDDR (args))); + } + case SCM_M_IF: + return scm_list_4 (scm_sym_if, unmemoize (scm_car (args)), + unmemoize (scm_cadr (args)), unmemoize (scm_cddr (args))); + case SCM_M_LAMBDA: + { + SCM body = CAR (args), spec = CDDR (args); + + if (scm_is_null (CDR (spec))) + return scm_list_3 (scm_sym_lambda, + scm_make_list (CAR (spec), sym_placeholder), + unmemoize (CAR (args))); + else if (scm_is_null (SCM_CDDR (spec))) + { + SCM formals = scm_make_list (CAR (spec), sym_placeholder); + return scm_list_3 (scm_sym_lambda, + scm_is_true (CADR (spec)) + ? scm_cons_star (sym_placeholder, formals) + : formals, + unmemoize (CAR (args))); + } + else + { + SCM alt, tail; + + alt = CADDR (CDDDR (spec)); + if (scm_is_true (alt)) + tail = CDR (unmemoize (alt)); + else + tail = SCM_EOL; + + return scm_cons + (sym_case_lambda_star, + scm_cons (scm_list_2 (scm_list_5 (CAR (spec), + CADR (spec), + CADDR (spec), + CADDDR (spec), + unmemoize_exprs (CADR (CDDDR (spec)))), + unmemoize (body)), + tail)); + } + } + case SCM_M_LET: + return scm_list_3 (scm_sym_let, + unmemoize_bindings (CAR (args)), + unmemoize (CDR (args))); + case SCM_M_QUOTE: + return scm_list_2 (scm_sym_quote, args); + case SCM_M_LEXICAL_REF: + return unmemoize_lexical (args); + case SCM_M_LEXICAL_SET: + return scm_list_3 (scm_sym_set_x, unmemoize_lexical (CAR (args)), + unmemoize (CDR (args))); + case SCM_M_TOPLEVEL_REF: + return args; + case SCM_M_TOPLEVEL_SET: + return scm_list_3 (scm_sym_set_x, CAR (args), unmemoize (CDR (args))); + case SCM_M_MODULE_REF: + return SCM_VARIABLEP (args) ? args + : scm_list_3 (scm_is_true (CDDR (args)) ? scm_sym_at : scm_sym_atat, + scm_i_finite_list_copy (CAR (args)), + CADR (args)); + case SCM_M_MODULE_SET: + return scm_list_3 (scm_sym_set_x, + SCM_VARIABLEP (CDR (args)) ? CDR (args) + : scm_list_3 (scm_is_true (CDDDR (args)) + ? scm_sym_at : scm_sym_atat, + scm_i_finite_list_copy (CADR (args)), + CADDR (args)), + unmemoize (CAR (args))); + case SCM_M_PROMPT: + return scm_list_4 (scm_sym_at_prompt, + unmemoize (CAR (args)), + unmemoize (CADR (args)), + unmemoize (CDDR (args))); + default: + abort (); + } +} + + + + +SCM_DEFINE (scm_memoized_p, "memoized?", 1, 0, 0, + (SCM obj), + "Return @code{#t} if @var{obj} is memoized.") +#define FUNC_NAME s_scm_memoized_p +{ + return scm_from_bool (SCM_MEMOIZED_P (obj)); +} +#undef FUNC_NAME + +SCM_DEFINE (scm_unmemoize_expression, "unmemoize-expression", 1, 0, 0, + (SCM m), + "Unmemoize the memoized expression @var{m}.") +#define FUNC_NAME s_scm_unmemoize_expression +{ + SCM_VALIDATE_MEMOIZED (1, m); + return unmemoize (m); +} +#undef FUNC_NAME + +SCM_DEFINE (scm_memoized_expression_typecode, "memoized-expression-typecode", 1, 0, 0, + (SCM m), + "Return the typecode from the memoized expression @var{m}.") +#define FUNC_NAME s_scm_memoized_expression_typecode +{ + SCM_VALIDATE_MEMOIZED (1, m); + + /* The tag is a 16-bit integer so it fits in an inum. */ + return SCM_I_MAKINUM (SCM_MEMOIZED_TAG (m)); +} +#undef FUNC_NAME + +SCM_DEFINE (scm_memoized_expression_data, "memoized-expression-data", 1, 0, 0, + (SCM m), + "Return the data from the memoized expression @var{m}.") +#define FUNC_NAME s_scm_memoized_expression_data +{ + SCM_VALIDATE_MEMOIZED (1, m); + return SCM_MEMOIZED_ARGS (m); +} +#undef FUNC_NAME + +SCM_DEFINE (scm_memoized_typecode, "memoized-typecode", 1, 0, 0, + (SCM sym), + "Return the memoized typecode corresponding to the symbol @var{sym}.") +#define FUNC_NAME s_scm_memoized_typecode +{ + int i; + + SCM_VALIDATE_SYMBOL (1, sym); + + for (i = 0; i < sizeof(memoized_tags)/sizeof(const char*); i++) + if (strcmp (scm_i_symbol_chars (sym), memoized_tags[i]) == 0) + return scm_from_int32 (i); + + return SCM_BOOL_F; +} +#undef FUNC_NAME + +SCM_SYMBOL (scm_unbound_variable_key, "unbound-variable"); +static void error_unbound_variable (SCM symbol) SCM_NORETURN; +static void error_unbound_variable (SCM symbol) +{ + scm_error (scm_unbound_variable_key, NULL, "Unbound variable: ~S", + scm_list_1 (symbol), SCM_BOOL_F); +} + +SCM_DEFINE (scm_memoize_variable_access_x, "memoize-variable-access!", 2, 0, 0, + (SCM m, SCM mod), + "Look up and cache the variable that @var{m} will access, returning the variable.") +#define FUNC_NAME s_scm_memoize_variable_access_x +{ + SCM mx; + SCM_VALIDATE_MEMOIZED (1, m); + mx = SCM_MEMOIZED_ARGS (m); + switch (SCM_MEMOIZED_TAG (m)) + { + case SCM_M_TOPLEVEL_REF: + if (SCM_VARIABLEP (mx)) + return mx; + else + { + SCM var = scm_module_variable (mod, mx); + if (scm_is_false (var) || scm_is_false (scm_variable_bound_p (var))) + error_unbound_variable (mx); + SCM_SET_SMOB_OBJECT (m, var); + return var; + } + + case SCM_M_TOPLEVEL_SET: + { + SCM var = CAR (mx); + if (SCM_VARIABLEP (var)) + return var; + else + { + var = scm_module_variable (mod, var); + if (scm_is_false (var)) + error_unbound_variable (CAR (mx)); + SCM_SETCAR (mx, var); + return var; + } + } + + case SCM_M_MODULE_REF: + if (SCM_VARIABLEP (mx)) + return mx; + else + { + SCM var; + mod = scm_resolve_module (CAR (mx)); + if (scm_is_true (CDDR (mx))) + mod = scm_module_public_interface (mod); + var = scm_module_lookup (mod, CADR (mx)); + if (scm_is_false (scm_variable_bound_p (var))) + error_unbound_variable (CADR (mx)); + SCM_SET_SMOB_OBJECT (m, var); + return var; + } + + case SCM_M_MODULE_SET: + /* FIXME: not quite threadsafe */ + if (SCM_VARIABLEP (CDR (mx))) + return CDR (mx); + else + { + SCM var; + mod = scm_resolve_module (CADR (mx)); + if (scm_is_true (CDDDR (mx))) + mod = scm_module_public_interface (mod); + var = scm_module_lookup (mod, CADDR (mx)); + SCM_SETCDR (mx, var); + return var; + } + + default: + scm_wrong_type_arg (FUNC_NAME, 1, m); + return SCM_BOOL_F; + } +} +#undef FUNC_NAME + + + + +void +scm_init_memoize () +{ + scm_tc16_memoized = scm_make_smob_type ("%memoized", 0); + scm_set_smob_print (scm_tc16_memoized, scm_print_memoized); + + scm_tc16_memoizer = scm_make_smob_type ("memoizer", 0); + +#include "libguile/memoize.x" + + list_of_guile = scm_list_1 (scm_from_latin1_symbol ("guile")); +} + +/* + Local Variables: + c-file-style: "gnu" + End: +*/