chibi-scheme/eval.c
2009-04-03 17:58:03 +09:00

1760 lines
56 KiB
C

/* eval.c -- evaluator library implementation */
/* Copyright (c) 2009 Alex Shinn. All rights reserved. */
/* BSD-style license: http://synthcode.com/license.txt */
#include "eval.h"
/************************************************************************/
static int scheme_initialized_p = 0;
static sexp continuation_resumer, final_resumer;
static sexp the_interaction_env_symbol;
static sexp the_err_handler_symbol, the_compile_error_symbol;
static sexp the_cur_in_symbol, the_cur_out_symbol, the_cur_err_symbol;
#if USE_DEBUG
#include "debug.c"
#else
#define print_stack(...)
#define print_bytecode(...)
#define sexp_disasm(...)
#endif
static sexp analyze (sexp x, sexp context);
static void generate (sexp x, sexp context);
static sexp sexp_make_null_env (sexp version);
static sexp sexp_make_standard_env (sexp version);
/********************** environment utilities ***************************/
static sexp env_cell(sexp e, sexp key) {
sexp ls;
do {
for (ls=sexp_env_bindings(e); sexp_pairp(ls); ls=sexp_cdr(ls))
if (sexp_caar(ls) == key)
return sexp_car(ls);
e = sexp_env_parent(e);
} while (e);
return NULL;
}
static sexp env_cell_create(sexp e, sexp key, sexp value) {
sexp cell = env_cell(e, key);
if (! cell) {
cell = sexp_cons(key, value);
while (sexp_env_parent(e))
e = sexp_env_parent(e);
sexp_env_bindings(e) = sexp_cons(cell, sexp_env_bindings(e));
}
return cell;
}
static sexp env_global_ref(sexp e, sexp key, sexp dflt) {
sexp cell;
while (sexp_env_parent(e))
e = sexp_env_parent(e);
cell = env_cell(e, key);
return (cell ? sexp_cdr(cell) : dflt);
}
static void env_define(sexp e, sexp key, sexp value) {
sexp cell = sexp_assq(key, sexp_env_bindings(e));
if (cell != SEXP_FALSE)
sexp_cdr(cell) = value;
else
sexp_push(sexp_env_bindings(e), sexp_cons(key, value));
}
static sexp extend_env (sexp env, sexp vars, sexp value) {
sexp e = sexp_alloc_type(env, SEXP_ENV);
sexp_env_parent(e) = env;
sexp_env_bindings(e) = SEXP_NULL;
for ( ; sexp_pairp(vars); vars = sexp_cdr(vars))
sexp_push(sexp_env_bindings(e), sexp_cons(sexp_car(vars), value));
return e;
}
static sexp sexp_reverse_flatten_dot (sexp ls) {
sexp res;
for (res=SEXP_NULL; sexp_pairp(ls); ls=sexp_cdr(ls))
sexp_push(res, sexp_car(ls));
return (sexp_nullp(ls) ? res : sexp_cons(ls, res));
}
static sexp sexp_flatten_dot (sexp ls) {
return sexp_nreverse(sexp_reverse_flatten_dot(ls));
}
static int sexp_param_index (sexp lambda, sexp name) {
sexp ls = sexp_lambda_params(lambda);
int i = 0;
for (i=0; sexp_pairp(ls); ls=sexp_cdr(ls), i++)
if (sexp_car(ls) == name)
return i;
if (ls == name)
return i;
ls = sexp_lambda_locals(lambda);
for (i=-1; sexp_pairp(ls); ls=sexp_cdr(ls), i--)
if (sexp_car(ls) == name)
return i-4;
return -10000;
}
/************************* bytecode utilities ***************************/
static void shrink_bcode(sexp context, sexp_uint_t i) {
sexp tmp;
if (sexp_bytecode_length(sexp_context_bc(context)) != i) {
tmp = sexp_alloc_tagged(sexp_sizeof(bytecode) + i, SEXP_BYTECODE);
sexp_bytecode_length(tmp) = i;
sexp_bytecode_literals(tmp)
= sexp_bytecode_literals(sexp_context_bc(context));
memcpy(sexp_bytecode_data(tmp),
sexp_bytecode_data(sexp_context_bc(context)),
i);
sexp_context_bc(context) = tmp;
}
}
static void expand_bcode(sexp context, sexp_uint_t size) {
sexp tmp;
if (sexp_bytecode_length(sexp_context_bc(context))
< (sexp_context_pos(context))+size) {
tmp = sexp_alloc_tagged(sexp_sizeof(bytecode)
+ sexp_bytecode_length(sexp_context_bc(context))*2,
SEXP_BYTECODE);
sexp_bytecode_length(tmp)
= sexp_bytecode_length(sexp_context_bc(context))*2;
sexp_bytecode_literals(tmp)
= sexp_bytecode_literals(sexp_context_bc(context));
memcpy(sexp_bytecode_data(tmp),
sexp_bytecode_data(sexp_context_bc(context)),
sexp_bytecode_length(sexp_context_bc(context)));
sexp_context_bc(context) = tmp;
}
}
static void emit(char c, sexp context) {
expand_bcode(context, 1);
sexp_bytecode_data(sexp_context_bc(context))[sexp_context_pos(context)++] = c;
}
static void emit_word(sexp_uint_t val, sexp context) {
unsigned char *data;
expand_bcode(context, sizeof(sexp));
data = sexp_bytecode_data(sexp_context_bc(context));
*((sexp_uint_t*)(&(data[sexp_context_pos(context)]))) = val;
sexp_context_pos(context) += sizeof(sexp);
}
static void emit_push(sexp obj, sexp context) {
emit(OP_PUSH, context);
emit_word((sexp_uint_t)obj, context);
if (sexp_pointerp(obj))
sexp_push(sexp_bytecode_literals(sexp_context_bc(context)), obj);
}
static sexp sexp_make_procedure(sexp flags, sexp num_args,
sexp bc, sexp vars) {
sexp proc = sexp_alloc_type(procedure, SEXP_PROCEDURE);
sexp_procedure_flags(proc) = (char) (sexp_uint_t) flags;
sexp_procedure_num_args(proc) = (unsigned short) (sexp_uint_t) num_args;
sexp_procedure_code(proc) = bc;
sexp_procedure_vars(proc) = vars;
return proc;
}
static sexp sexp_make_macro (sexp p, sexp e) {
sexp mac = sexp_alloc_type(macro, SEXP_MACRO);
sexp_macro_env(mac) = e;
sexp_macro_proc(mac) = p;
return mac;
}
static sexp sexp_make_synclo (sexp env, sexp fv, sexp expr) {
sexp res;
if (sexp_synclop(expr))
return expr;
res = sexp_alloc_type(synclo, SEXP_SYNCLO);
sexp_synclo_env(res) = env;
sexp_synclo_free_vars(res) = fv;
sexp_synclo_expr(res) = expr;
return res;
}
/* internal AST */
static sexp sexp_make_lambda(sexp params) {
sexp res = sexp_alloc_type(lambda, SEXP_LAMBDA);
sexp_lambda_params(res) = params;
sexp_lambda_fv(res) = SEXP_NULL;
sexp_lambda_sv(res) = SEXP_NULL;
sexp_lambda_locals(res) = SEXP_NULL;
sexp_lambda_defs(res) = SEXP_NULL;
return res;
}
static sexp sexp_make_set(sexp var, sexp value) {
sexp res = sexp_alloc_type(set, SEXP_SET);
sexp_set_var(res) = var;
sexp_set_value(res) = value;
return res;
}
static sexp sexp_make_ref(sexp name, sexp cell) {
sexp res = sexp_alloc_type(ref, SEXP_REF);
sexp_ref_name(res) = name;
sexp_ref_cell(res) = cell;
return res;
}
static sexp sexp_make_cnd(sexp test, sexp pass, sexp fail) {
sexp res = sexp_alloc_type(cnd, SEXP_CND);
sexp_cnd_test(res) = test;
sexp_cnd_pass(res) = pass;
sexp_cnd_fail(res) = fail;
return res;
}
static sexp sexp_make_lit(sexp value) {
sexp res = sexp_alloc_type(lit, SEXP_LIT);
sexp_lit_value(res) = value;
return res;
}
static sexp sexp_make_context(sexp *stack, sexp env) {
sexp res = sexp_alloc_type(context, SEXP_CONTEXT);
if (! stack)
stack = (sexp*) sexp_alloc(sizeof(sexp)*INIT_STACK_SIZE);
if (! env)
env = sexp_make_standard_env(sexp_make_integer(5));
sexp_context_bc(res)
= sexp_alloc_tagged(sexp_sizeof(bytecode)+INIT_BCODE_SIZE, SEXP_BYTECODE);
sexp_bytecode_length(sexp_context_bc(res)) = INIT_BCODE_SIZE;
sexp_bytecode_literals(sexp_context_bc(res)) = SEXP_NULL;
sexp_context_lambda(res) = SEXP_FALSE;
sexp_context_stack(res) = stack;
sexp_context_env(res) = env;
sexp_context_depth(res) = 0;
sexp_context_pos(res) = 0;
sexp_context_top(res) = 0;
sexp_context_tailp(res) = 1;
return res;
}
static sexp sexp_child_context(sexp context, sexp lambda) {
sexp ctx = sexp_make_context(sexp_context_stack(context),
sexp_context_env(context));
sexp_context_lambda(ctx) = lambda;
sexp_context_env(ctx) = sexp_context_env(context);
sexp_context_top(ctx) = sexp_context_top(context);
return ctx;
}
#define sexp_idp(x) (sexp_symbolp(x) || (sexp_synclop(x) && sexp_symbolp(sexp_synclo_expr(x))))
static sexp sexp_identifierp (sexp x) {
return sexp_make_boolean(sexp_idp(x));
}
static sexp sexp_identifier_eq (sexp e1, sexp id1, sexp e2, sexp id2) {
sexp cell, lam1=SEXP_FALSE, lam2=SEXP_FALSE;
if (sexp_synclop(id1)) {
e1 = sexp_synclo_env(id1);
id1 = sexp_synclo_expr(id1);
}
if (sexp_synclop(id2)) {
e2 = sexp_synclo_env(id2);
id2 = sexp_synclo_expr(id2);
}
cell = env_cell(e1, id1);
if (cell && sexp_lambdap(sexp_cdr(cell)))
lam1 = sexp_cdr(cell);
cell = env_cell(e2, id2);
if (cell && sexp_lambdap(sexp_cdr(cell)))
lam2 = sexp_cdr(cell);
return sexp_make_boolean((id1 == id2) && (lam1 == lam2));
}
/************************* the compiler ***************************/
static sexp sexp_compile_error(char *message, sexp irritants) {
return sexp_make_exception(the_compile_error_symbol,
sexp_c_string(message),
irritants, SEXP_FALSE, SEXP_FALSE);
}
#define analyze_check_exception(x) do {if (sexp_exceptionp(x)) \
return (x); \
} while (0)
#define analyze_bind(var, x, context) do {(var) = analyze(x,context); \
analyze_check_exception(var); \
} while (0)
static sexp analyze_app (sexp x, sexp context) {
sexp res=SEXP_NULL, tmp;
for ( ; sexp_pairp(x); x=sexp_cdr(x)) {
analyze_bind(tmp, sexp_car(x), context);
sexp_push(res, tmp);
}
return sexp_nreverse(res);
}
static sexp analyze_seq (sexp ls, sexp context) {
sexp res, tmp;
if (sexp_nullp(ls))
res = SEXP_VOID;
else if (sexp_nullp(sexp_cdr(ls)))
res = analyze(sexp_car(ls), context);
else {
res = sexp_alloc_type(seq, SEXP_SEQ);
tmp = analyze_app(ls, context);
analyze_check_exception(tmp);
sexp_seq_ls(res) = tmp;
}
return res;
}
static sexp analyze_var_ref (sexp x, sexp context) {
sexp cell = env_cell(sexp_context_env(context), x);
if (! cell) {
if (sexp_synclop(x)) {
cell = env_cell_create(sexp_synclo_env(x),
sexp_synclo_expr(x),
SEXP_UNDEF);
x = sexp_synclo_expr(x);
} else {
cell = env_cell_create(sexp_context_env(context), x, SEXP_UNDEF);
}
}
return sexp_make_ref(x, cell);
}
static sexp analyze_set (sexp x, sexp context) {
sexp ref, value;
ref = analyze_var_ref(sexp_cadr(x), context);
if (sexp_lambdap(sexp_ref_loc(ref)))
sexp_insert(sexp_lambda_sv(sexp_ref_loc(ref)), sexp_ref_name(ref));
analyze_check_exception(ref);
analyze_bind(value, sexp_caddr(x), context);
return sexp_make_set(ref, value);
}
static sexp analyze_lambda (sexp x, sexp context) {
sexp res, body, ls, tmp, name, value, defs=SEXP_NULL;
/* verify syntax */
if (! (sexp_pairp(sexp_cdr(x)) && sexp_pairp(sexp_cddr(x))))
return sexp_compile_error("bad lambda syntax", sexp_list1(x));
for (ls=sexp_cadr(x); sexp_pairp(ls); ls=sexp_cdr(ls))
if (! sexp_idp(sexp_car(ls)))
return sexp_compile_error("non-symbol parameter", sexp_list1(x));
else if (sexp_memq(sexp_car(ls), sexp_cdr(ls)) != SEXP_FALSE)
return sexp_compile_error("duplicate parameter", sexp_list1(x));
/* build lambda and analyze body */
res = sexp_make_lambda(sexp_cadr(x));
context = sexp_child_context(context, res);
sexp_context_env(context)
= extend_env(sexp_context_env(context),
sexp_flatten_dot(sexp_lambda_params(res)),
res);
sexp_env_lambda(sexp_context_env(context)) = res;
body = analyze_seq(sexp_cddr(x), context);
analyze_check_exception(body);
/* delayed analyze internal defines */
for (ls=sexp_lambda_defs(res); sexp_pairp(ls); ls=sexp_cdr(ls)) {
tmp = sexp_car(ls);
if (sexp_pairp(sexp_cadr(tmp))) {
name = sexp_caadr(tmp);
value = analyze_lambda(sexp_cons(SEXP_VOID, sexp_cons(sexp_cdadr(tmp),
sexp_cddr(tmp))),
context);
} else {
name = sexp_cadr(tmp);
value = analyze(sexp_caddr(tmp), context);
}
analyze_check_exception(value);
sexp_push(defs, sexp_make_set(analyze_var_ref(name, context), value));
}
if (sexp_pairp(defs)) {
if (! sexp_seqp(body)) {
tmp = sexp_alloc_type(seq, SEXP_SEQ);
sexp_seq_ls(tmp) = sexp_list1(body);
body = tmp;
}
sexp_seq_ls(body) = sexp_append(defs, sexp_seq_ls(body));
}
sexp_lambda_body(res) = body;
return res;
}
static sexp analyze_if (sexp x, sexp context) {
sexp test, pass, fail, fail_expr;
analyze_bind(test, sexp_cadr(x), context);
analyze_bind(pass, sexp_caddr(x), context);
fail_expr = sexp_pairp(sexp_cdddr(x)) ? sexp_cadddr(x) : SEXP_VOID;
analyze_bind(fail, fail_expr, context);
return sexp_make_cnd(test, pass, fail);
}
static sexp analyze_define (sexp x, sexp context) {
sexp ref, name, value, env = sexp_context_env(context);
name = (sexp_pairp(sexp_cadr(x)) ? sexp_caadr(x) : sexp_cadr(x));
if (sexp_env_lambda(env) && sexp_lambdap(sexp_env_lambda(env))) {
sexp_push(sexp_env_bindings(env),
sexp_cons(name, sexp_context_lambda(context)));
sexp_push(sexp_lambda_sv(sexp_env_lambda(env)), name);
sexp_push(sexp_lambda_locals(sexp_env_lambda(env)), name);
sexp_push(sexp_lambda_defs(sexp_env_lambda(env)), x);
return SEXP_VOID;
} else {
env_cell_create(env, name, SEXP_VOID);
}
if (sexp_pairp(sexp_cadr(x)))
value = analyze_lambda(sexp_cons(SEXP_VOID,
sexp_cons(sexp_cdadr(x), sexp_cddr(x))),
context);
else
value = analyze(sexp_caddr(x), context);
analyze_check_exception(value);
ref = analyze_var_ref(name, context);
analyze_check_exception(ref);
return sexp_make_set(ref, value);
}
static sexp analyze_define_syntax (sexp x, sexp context) {
sexp name = sexp_cadr(x), cell, proc;
if (sexp_env_parent(sexp_context_env(context)))
return sexp_compile_error("non-top-level define-syntax", sexp_list1(x));
proc = eval_in_context(sexp_caddr(x), context);
analyze_check_exception(proc);
cell = env_cell_create(sexp_context_env(context), name, SEXP_VOID);
sexp_cdr(cell) = sexp_make_macro(proc, sexp_context_env(context));
return SEXP_VOID;
}
static sexp analyze_bind_syntax (sexp ls, sexp eval_ctx, sexp bind_ctx) {
sexp proc;
for ( ; sexp_pairp(ls); ls=sexp_cdr(ls)) {
proc = eval_in_context(sexp_cadar(ls), eval_ctx);
analyze_check_exception(proc);
sexp_push(sexp_env_bindings(sexp_context_env(bind_ctx)),
sexp_cons(sexp_caar(ls),
sexp_make_macro(proc, sexp_context_env(eval_ctx))));
}
return SEXP_VOID;
}
static sexp analyze_let_syntax (sexp x, sexp context) {
sexp env, ctx, tmp;
env = sexp_alloc_type(env, SEXP_ENV);
sexp_env_parent(env) = sexp_env_parent(sexp_context_env(context));
sexp_env_bindings(env) = sexp_env_bindings(sexp_context_env(context));
ctx = sexp_child_context(context, sexp_context_lambda(context));
sexp_context_env(ctx) = env;
tmp = analyze_bind_syntax(sexp_cadr(x), ctx, context);
analyze_check_exception(tmp);
return analyze_seq(sexp_cddr(x), ctx);
}
static sexp analyze_letrec_syntax (sexp x, sexp context) {
sexp tmp = analyze_bind_syntax(sexp_cadr(x), context, context);
analyze_check_exception(tmp);
return analyze_seq(sexp_cddr(x), context);
}
static sexp analyze (sexp x, sexp context) {
sexp op, cell, res;
loop:
if (sexp_pairp(x)) {
if (sexp_listp(x) == SEXP_FALSE) {
res = sexp_compile_error("dotted list in source", sexp_list1(x));
} else if (sexp_idp(sexp_car(x))) {
if (sexp_synclop(sexp_car(x)))
cell = env_cell(sexp_synclo_env(sexp_car(x)),
sexp_synclo_expr(sexp_car(x)));
else
cell = env_cell(sexp_context_env(context), sexp_car(x));
if (! cell) return analyze_app(x, context);
op = sexp_cdr(cell);
if (sexp_corep(op)) {
switch (sexp_core_code(op)) {
case CORE_DEFINE:
res = analyze_define(x, context); break;
case CORE_SET:
res = analyze_set(x, context); break;
case CORE_LAMBDA:
res = analyze_lambda(x, context); break;
case CORE_IF:
res = analyze_if(x, context); break;
case CORE_BEGIN:
res = analyze_seq(x, context); break;
case CORE_QUOTE:
res = sexp_make_lit(sexp_cadr(x)); break;
case CORE_DEFINE_SYNTAX:
res = analyze_define_syntax(x, context); break;
case CORE_LET_SYNTAX:
res = analyze_let_syntax(x, context); break;
case CORE_LETREC_SYNTAX:
res = analyze_letrec_syntax(x, context); break;
default:
res = sexp_compile_error("unknown core form", sexp_list1(op)); break;
}
} else if (sexp_macrop(op)) {
x = apply(sexp_macro_proc(op),
sexp_list3(x, sexp_context_env(context), sexp_macro_env(op)),
sexp_child_context(context, sexp_context_lambda(context)));
/* sexp_debug("expand => ", x, context); */
goto loop;
} else if (sexp_opcodep(op)) {
res = sexp_length(sexp_cdr(x));
if (sexp_unbox_integer(res) < sexp_opcode_num_args(op)) {
res = sexp_compile_error("not enough args for opcode", sexp_list1(x));
} else if ((sexp_unbox_integer(res) > sexp_opcode_num_args(op))
&& (! sexp_opcode_variadic_p(op))) {
res = sexp_compile_error("too many args for opcode", sexp_list1(x));
} else {
res = analyze_app(sexp_cdr(x), context);
analyze_check_exception(res);
sexp_push(res, op);
}
} else {
res = analyze_app(x, context);
}
} else {
res = analyze_app(x, context);
}
} else if (sexp_idp(x)) {
res = analyze_var_ref(x, context);
} else if (sexp_synclop(x)) {
context = sexp_child_context(context, sexp_context_lambda(context));
sexp_context_env(context) = sexp_synclo_env(x);
x = sexp_synclo_expr(x);
goto loop;
} else {
res = x;
}
return res;
}
static sexp_sint_t sexp_context_make_label (sexp context) {
sexp_sint_t label = sexp_context_pos(context);
sexp_context_pos(context) += sizeof(sexp_uint_t);
return label;
}
static void sexp_context_patch_label (sexp context, sexp_sint_t label) {
sexp bc = sexp_context_bc(context);
unsigned char *data = sexp_bytecode_data(bc)+label;
*((sexp_sint_t*)data) = sexp_context_pos(context)-label;
}
static sexp finalize_bytecode (sexp context) {
emit(OP_RET, context);
shrink_bcode(context, sexp_context_pos(context));
/* sexp_disasm(sexp_context_bc(context), */
/* env_global_ref(sexp_context_env(context), */
/* the_cur_err_symbol, */
/* SEXP_FALSE)); */
return sexp_context_bc(context);
}
static void generate_lit (sexp value, sexp context) {
emit_push(value, context);
}
static void generate_seq (sexp app, sexp context) {
sexp head=app, tail=sexp_cdr(app);
sexp_uint_t tailp = sexp_context_tailp(context);
sexp_context_tailp(context) = 0;
for ( ; sexp_pairp(tail); head=tail, tail=sexp_cdr(tail))
if (sexp_pointerp(sexp_car(head)) && (! sexp_litp(sexp_car(head)))) {
generate(sexp_car(head), context);
emit(OP_DROP, context);
sexp_context_depth(context)--;
}
sexp_context_tailp(context) = tailp;
generate(sexp_car(head), context);
}
static void generate_cnd (sexp cnd, sexp context) {
sexp_sint_t label1, label2, tailp=sexp_context_tailp(context);
sexp_context_tailp(context) = 0;
generate(sexp_cnd_test(cnd), context);
sexp_context_tailp(context) = tailp;
emit(OP_JUMP_UNLESS, context);
sexp_context_depth(context)--;
label1 = sexp_context_make_label(context);
generate(sexp_cnd_pass(cnd), context);
emit(OP_JUMP, context);
sexp_context_depth(context)--;
label2 = sexp_context_make_label(context);
sexp_context_patch_label(context, label1);
generate(sexp_cnd_fail(cnd), context);
sexp_context_patch_label(context, label2);
}
static void generate_non_global_ref (sexp name, sexp cell, sexp lambda,
sexp fv, sexp context, int unboxp) {
sexp_uint_t i;
sexp loc = sexp_cdr(cell);
if (loc == lambda && sexp_lambdap(lambda)) {
/* local ref */
emit(OP_LOCAL_REF, context);
emit_word(sexp_param_index(lambda, name), context);
} else {
/* closure ref */
for (i=0; sexp_pairp(fv); fv=sexp_cdr(fv), i++)
if ((name == sexp_ref_name(sexp_car(fv)))
&& (loc == sexp_ref_loc(sexp_car(fv))))
break;
emit(OP_CLOSURE_REF, context);
emit_word(i, context);
}
if (unboxp && (sexp_memq(name, sexp_lambda_sv(loc)) != SEXP_FALSE))
emit(OP_CDR, context);
sexp_context_depth(context)++;
}
static void generate_ref (sexp ref, sexp context, int unboxp) {
sexp lam;
if (! sexp_lambdap(sexp_ref_loc(ref))) {
/* global ref */
if (unboxp) {
emit((sexp_cdr(sexp_ref_cell(ref)) == SEXP_UNDEF)
? OP_GLOBAL_REF : OP_GLOBAL_KNOWN_REF,
context);
emit_word((sexp_uint_t)sexp_ref_cell(ref), context);
} else
emit_push(sexp_ref_cell(ref), context);
} else {
lam = sexp_context_lambda(context);
generate_non_global_ref(sexp_ref_name(ref), sexp_ref_cell(ref), lam,
sexp_lambda_fv(lam), context, unboxp);
}
}
static void generate_set (sexp set, sexp context) {
sexp ref = sexp_set_var(set), lambda;
/* compile the value */
sexp_context_tailp(context) = 0;
generate(sexp_set_value(set), context);
if (! sexp_lambdap(sexp_ref_loc(ref))) {
/* global vars are set directly */
emit_push(sexp_ref_cell(ref), context);
emit(OP_SET_CDR, context);
} else {
lambda = sexp_ref_loc(ref);
if (sexp_memq(sexp_ref_name(ref), sexp_lambda_sv(lambda)) != SEXP_FALSE) {
/* stack or closure mutable vars are boxed */
generate_ref(ref, context, 0);
emit(OP_SET_CDR, context);
} else {
/* internally defined variable */
emit(OP_LOCAL_SET, context);
emit_word(sexp_param_index(lambda, sexp_ref_name(ref)), context);
}
}
sexp_context_depth(context)--;
}
static void generate_opcode_app (sexp app, sexp context) {
sexp ls, op = sexp_car(app);
sexp_sint_t i, num_args = sexp_unbox_integer(sexp_length(sexp_cdr(app)));
sexp_context_tailp(context) = 0;
/* maybe push the default for an optional argument */
if ((num_args == sexp_opcode_num_args(op))
&& sexp_opcode_variadic_p(op)
&& sexp_opcode_default(op)
&& (sexp_opcode_class(op) != OPC_PARAMETER)) {
emit_push(sexp_opcode_default(op), context);
if (sexp_opcode_opt_param_p(op))
emit(OP_CDR, context);
sexp_context_depth(context)++;
num_args++;
}
/* push the arguments onto the stack */
ls = ((sexp_opcode_inverse(op)
&& (sexp_opcode_class(op) != OPC_ARITHMETIC_INV))
? sexp_cdr(app) : sexp_reverse(sexp_cdr(app)));
for ( ; sexp_pairp(ls); ls = sexp_cdr(ls))
generate(sexp_car(ls), context);
/* emit the actual operator call */
switch (sexp_opcode_class(op)) {
case OPC_ARITHMETIC_INV:
emit((num_args == 1) ? sexp_opcode_inverse(op)
: sexp_opcode_code(op), context);
break;
case OPC_ARITHMETIC_CMP:
if (num_args > 2) {
emit(OP_STACK_REF, context);
emit_word(2, context);
emit(OP_STACK_REF, context);
emit_word(2, context);
emit(sexp_opcode_code(op), context);
emit(OP_AND, context);
for (i=num_args-2; i>0; i--) {
emit(OP_STACK_REF, context);
emit_word(3, context);
emit(OP_STACK_REF, context);
emit_word(3, context);
emit(sexp_opcode_code(op), context);
emit(OP_AND, context);
emit(OP_AND, context);
}
} else
emit(sexp_opcode_code(op), context);
break;
case OPC_FOREIGN:
case OPC_TYPE_PREDICATE:
/* push the funtion pointer for foreign calls */
emit(sexp_opcode_code(op), context);
if (sexp_opcode_data(op))
emit_word((sexp_uint_t)sexp_opcode_data(op), context);
break;
case OPC_PARAMETER:
emit_push(sexp_opcode_default(op), context);
emit((num_args == 0 ? OP_CDR : OP_SET_CDR), context);
default:
emit(sexp_opcode_code(op), context);
}
/* emit optional folding of operator */
if ((num_args > 2)
&& (sexp_opcode_class(op) == OPC_ARITHMETIC
|| sexp_opcode_class(op) == OPC_ARITHMETIC_INV))
for (i=num_args-2; i>0; i--)
emit(sexp_opcode_code(op), context);
sexp_context_depth(context) -= (num_args-1);
}
static void generate_general_app (sexp app, sexp context) {
sexp ls;
sexp_uint_t len = sexp_unbox_integer(sexp_length(sexp_cdr(app))),
tailp = sexp_context_tailp(context);
/* push the arguments onto the stack */
sexp_context_tailp(context) = 0;
for (ls = sexp_reverse(sexp_cdr(app)); sexp_pairp(ls); ls = sexp_cdr(ls))
generate(sexp_car(ls), context);
/* push the operator onto the stack */
generate(sexp_car(app), context);
/* maybe overwrite the current frame */
emit((tailp ? OP_TAIL_CALL : OP_CALL), context);
emit_word((sexp_uint_t)sexp_make_integer(len), context);
sexp_context_depth(context) -= len;
}
static void generate_app (sexp app, sexp context) {
if (sexp_opcodep(sexp_car(app)))
generate_opcode_app(app, context);
else
generate_general_app(app, context);
}
static void generate_lambda (sexp lambda, sexp context) {
sexp fv, ls, ctx, flags, bc, len, ref, vec, prev_lambda, prev_fv;
sexp_uint_t k;
prev_lambda = sexp_context_lambda(context);
prev_fv = sexp_lambdap(prev_lambda) ? sexp_lambda_fv(prev_lambda) : SEXP_NULL;
fv = sexp_lambda_fv(lambda);
ctx = sexp_make_context(sexp_context_stack(context),
sexp_context_env(context));
sexp_context_lambda(ctx) = lambda;
/* allocate space for local vars */
for (ls=sexp_lambda_locals(lambda); sexp_pairp(ls); ls=sexp_cdr(ls))
emit_push(SEXP_VOID, ctx);
/* box mutable vars */
for (ls=sexp_lambda_sv(lambda); sexp_pairp(ls); ls=sexp_cdr(ls)) {
k = sexp_param_index(lambda, sexp_car(ls));
if (k >= 0) {
emit(OP_LOCAL_REF, ctx);
emit_word(k, ctx);
emit_push(sexp_car(ls), ctx);
emit(OP_CONS, ctx);
emit(OP_LOCAL_SET, ctx);
emit_word(k, ctx);
emit(OP_DROP, ctx);
}
}
generate(sexp_lambda_body(lambda), ctx);
flags = sexp_make_integer((sexp_listp(sexp_lambda_params(lambda))==SEXP_FALSE)
? 1 : 0);
len = sexp_length(sexp_lambda_params(lambda));
bc = finalize_bytecode(ctx);
if (sexp_nullp(fv)) {
/* shortcut, no free vars */
vec = sexp_make_vector(sexp_make_integer(0), SEXP_VOID);
generate_lit(sexp_make_procedure(flags, len, bc, vec), context);
} else {
/* push the closed vars */
emit_push(SEXP_VOID, context);
emit_push(sexp_length(fv), context);
emit(OP_MAKE_VECTOR, context);
sexp_context_depth(context)--;
for (k=0; sexp_pairp(fv); fv=sexp_cdr(fv), k++) {
ref = sexp_car(fv);
generate_non_global_ref(sexp_ref_name(ref), sexp_ref_cell(ref),
prev_lambda, prev_fv, context, 0);
emit_push(sexp_make_integer(k), context);
emit(OP_STACK_REF, context);
emit_word(3, context);
emit(OP_VECTOR_SET, context);
emit(OP_DROP, context);
sexp_context_depth(context)--;
}
/* push the additional procedure info and make the closure */
emit_push(bc, context);
emit_push(len, context);
emit_push(flags, context);
emit(OP_MAKE_PROCEDURE, context);
}
}
static void generate (sexp x, sexp context) {
if (sexp_pointerp(x)) {
switch (sexp_pointer_tag(x)) {
case SEXP_PAIR:
generate_app(x, context);
break;
case SEXP_LAMBDA:
generate_lambda(x, context);
break;
case SEXP_CND:
generate_cnd(x, context);
break;
case SEXP_REF:
generate_ref(x, context, 1);
break;
case SEXP_SET:
generate_set(x, context);
break;
case SEXP_SEQ:
generate_seq(sexp_seq_ls(x), context);
break;
case SEXP_LIT:
generate_lit(sexp_lit_value(x), context);
break;
default:
generate_lit(x, context);
}
} else {
generate_lit(x, context);
}
}
static sexp insert_free_var (sexp x, sexp fv) {
sexp name=sexp_ref_name(x), loc=sexp_ref_loc(x), ls;
for (ls=fv; sexp_pairp(ls); ls=sexp_cdr(ls))
if ((name == sexp_ref_name(sexp_car(ls)))
&& (loc == sexp_ref_loc(sexp_car(ls))))
return fv;
return sexp_cons(x, fv);
}
static sexp union_free_vars (sexp fv1, sexp fv2) {
if (sexp_nullp(fv2))
return fv1;
for ( ; sexp_pairp(fv1); fv1=sexp_cdr(fv1))
fv2 = insert_free_var(sexp_car(fv1), fv2);
return fv2;
}
static sexp diff_free_vars (sexp lambda, sexp fv, sexp params) {
sexp res = SEXP_NULL;
for ( ; sexp_pairp(fv); fv=sexp_cdr(fv))
if ((sexp_ref_loc(sexp_car(fv)) != lambda)
|| (sexp_memq(sexp_ref_name(sexp_car(fv)), params) == SEXP_FALSE))
sexp_push(res, sexp_car(fv));
return res;
}
static sexp free_vars (sexp x, sexp fv) {
sexp fv1, fv2;
if (sexp_lambdap(x)) {
fv1 = free_vars(sexp_lambda_body(x), SEXP_NULL);
fv2 = diff_free_vars(x,
fv1,
sexp_append(sexp_lambda_locals(x),
sexp_flatten_dot(sexp_lambda_params(x))));
sexp_lambda_fv(x) = fv2;
fv = union_free_vars(fv2, fv);
} else if (sexp_pairp(x)) {
for ( ; sexp_pairp(x); x=sexp_cdr(x))
fv = free_vars(sexp_car(x), fv);
} else if (sexp_cndp(x)) {
fv = free_vars(sexp_cnd_test(x), fv);
fv = free_vars(sexp_cnd_pass(x), fv);
fv = free_vars(sexp_cnd_fail(x), fv);
} else if (sexp_seqp(x)) {
for (x=sexp_seq_ls(x); sexp_pairp(x); x=sexp_cdr(x))
fv = free_vars(sexp_car(x), fv);
} else if (sexp_setp(x)) {
fv = free_vars(sexp_set_value(x), fv);
fv = free_vars(sexp_set_var(x), fv);
} else if (sexp_refp(x) && sexp_lambdap(sexp_ref_loc(x))) {
fv = insert_free_var(x, fv);
} else if (sexp_synclop(x)) {
fv = free_vars(sexp_synclo_expr(x), fv);
}
return fv;
}
static sexp make_param_list(sexp_uint_t i) {
sexp res = SEXP_NULL;
char sym[2]="a";
for (sym[0]+=i; i>0; i--) {
sym[0] = sym[0]-1;
res = sexp_cons(sexp_intern(sym), res);
}
return res;
}
static sexp make_opcode_procedure (sexp op, sexp_uint_t i, sexp env,
sexp *stack, sexp_sint_t top) {
sexp context, lambda, params, refs, ls, bc, res;
if (i == sexp_opcode_num_args(op) && sexp_opcode_proc(op))
return sexp_opcode_proc(op);
params = make_param_list(i);
lambda = sexp_make_lambda(params);
env = extend_env(env, params, lambda);
context = sexp_make_context(stack, env);
sexp_context_lambda(context) = lambda;
sexp_context_top(context) = top;
for (ls=params, refs=SEXP_NULL; sexp_pairp(ls); ls=sexp_cdr(ls))
sexp_push(refs, sexp_make_ref(sexp_car(ls), env_cell(env, sexp_car(ls))));
generate_opcode_app(sexp_cons(op, sexp_reverse(refs)), context);
bc = finalize_bytecode(context);
res = sexp_make_procedure(sexp_make_integer(0),
sexp_make_integer(i),
bc,
SEXP_VOID);
if (i == sexp_opcode_num_args(op))
sexp_opcode_proc(op) = res;
return res;
}
/*********************** the virtual machine **************************/
static sexp sexp_save_stack(sexp *stack, sexp_uint_t to) {
sexp res, *data;
sexp_uint_t i;
res = sexp_make_vector(sexp_make_integer(to), SEXP_VOID);
data = sexp_vector_data(res);
for (i=0; i<to; i++)
data[i] = stack[i];
return res;
}
static sexp_uint_t sexp_restore_stack(sexp saved, sexp *current) {
sexp_uint_t len = sexp_vector_length(saved), i;
sexp *from = sexp_vector_data(saved);
for (i=0; i<len; i++)
current[i] = from[i];
return len;
}
#define _ARG1 stack[top-1]
#define _ARG2 stack[top-2]
#define _ARG3 stack[top-3]
#define _ARG4 stack[top-4]
#define _ARG5 stack[top-5]
#define _PUSH(x) (stack[top++]=(x))
#define _WORD0 ((sexp*)ip)[0]
#define _UWORD0 ((sexp_uint_t*)ip)[0]
#define _SWORD0 ((sexp_sint_t*)ip)[0]
#define sexp_raise(msg, args) do {stack[top]=sexp_compile_error(msg, args); \
top++; \
goto call_error_handler;} \
while (0)
#define sexp_check_exception() do {if (sexp_exceptionp(_ARG1)) \
goto call_error_handler;} \
while (0)
sexp vm(sexp bc, sexp cp, sexp context, sexp* stack, sexp_sint_t top) {
unsigned char *ip=sexp_bytecode_data(bc);
sexp tmp1, tmp2, env=sexp_context_env(context);
sexp_sint_t i, j, k, fp=top-4;
loop:
/* print_stack(stack, top, fp, env_global_ref(env, the_cur_err_symbol, SEXP_FALSE)); */
/* fprintf(stderr, "%s\n", (*ip<=71)?reverse_opcode_names[*ip]:"UNKNOWN"); */
switch (*ip++) {
case OP_NOOP:
fprintf(stderr, "<<<NOOP>>>\n");
break;
case OP_ERROR:
call_error_handler:
tmp1 = env_global_ref(env, the_cur_err_symbol, SEXP_FALSE);
sexp_print_exception(_ARG1, tmp1);
tmp1 = env_global_ref(env, the_err_handler_symbol, SEXP_FALSE);
stack[top] = (sexp) 1;
stack[top+1] = sexp_make_integer(ip+4);
stack[top+2] = cp;
top += 3;
bc = sexp_procedure_code(tmp1);
ip = sexp_bytecode_data(bc);
cp = sexp_procedure_vars(tmp1);
break;
case OP_RESUMECC:
tmp1 = stack[fp-1];
top = sexp_restore_stack(sexp_vector_ref(cp, 0), stack);
fp = sexp_unbox_integer(_ARG1);
cp = _ARG2;
ip = (unsigned char*) sexp_unbox_integer(_ARG3);
i = sexp_unbox_integer(_ARG4);
top -= 4;
_ARG1 = tmp1;
break;
case OP_CALLCC:
tmp1 = _ARG1;
i = 1;
stack[top] = sexp_make_integer(1);
stack[top+1] = sexp_make_integer(ip);
stack[top+2] = cp;
stack[top+3] = sexp_make_integer(fp);
tmp2 = sexp_vector(1, sexp_save_stack(stack, top+4));
_ARG1 = sexp_make_procedure(sexp_make_integer(0),
sexp_make_integer(1),
continuation_resumer,
tmp2);
top++;
ip -= sizeof(sexp);
goto make_call;
break;
case OP_APPLY1:
tmp1 = _ARG1;
tmp2 = _ARG2;
i = sexp_unbox_integer(sexp_length(tmp2));
top += (i-2);
for ( ; sexp_pairp(tmp2); tmp2=sexp_cdr(tmp2), top--)
_ARG1 = sexp_car(tmp2);
top += i+1;
ip -= sizeof(sexp);
goto make_call;
case OP_TAIL_CALL:
i = sexp_unbox_integer(_WORD0); /* number of params */
tmp1 = _ARG1; /* procedure to call */
/* save frame info */
j = sexp_unbox_integer(stack[fp]);
ip = ((unsigned char*) sexp_unbox_integer(stack[fp+1])) - sizeof(sexp);
cp = stack[fp+2];
/* copy new args into place */
for (k=0; k<i; k++)
stack[fp-j+k] = stack[top-1-i+k];
top = fp+i-j+1;
fp = sexp_unbox_integer(stack[fp+3]);
goto make_call;
case OP_CALL:
if (top >= INIT_STACK_SIZE)
sexp_raise("out of stack space", SEXP_NULL);
i = sexp_unbox_integer(_WORD0);
tmp1 = _ARG1;
make_call:
if (sexp_opcodep(tmp1)) {
/* compile non-inlined opcode applications on the fly */
tmp1 = make_opcode_procedure(tmp1, i, env, stack, top);
if (sexp_exceptionp(tmp1)) {
_ARG1 = tmp1;
goto call_error_handler;
}
}
if (! sexp_procedurep(tmp1))
sexp_raise("non procedure application", sexp_list1(tmp1));
j = i - sexp_unbox_integer(sexp_procedure_num_args(tmp1));
if (j < 0)
sexp_raise("not enough args", sexp_list2(tmp1, sexp_make_integer(i)));
if (j > 0) {
if (sexp_procedure_variadic_p(tmp1)) {
stack[top-i-1] = sexp_cons(stack[top-i-1], SEXP_NULL);
for (k=top-i; k<top-(i-j)-1; k++)
stack[top-i-1] = sexp_cons(stack[k], stack[top-i-1]);
for ( ; k<top; k++)
stack[k-j+1] = stack[k];
top -= (j-1);
i -= (j-1);
} else {
sexp_raise("too many args", sexp_list2(tmp1, sexp_make_integer(i)));
}
} else if (sexp_procedure_variadic_p(tmp1)) {
/* shift stack, set extra arg to null */
for (k=top; k>=top-i; k--)
stack[k] = stack[k-1];
stack[top-i-1] = SEXP_NULL;
top++;
i++;
}
_ARG1 = sexp_make_integer(i);
stack[top] = sexp_make_integer(ip+sizeof(sexp));
stack[top+1] = cp;
stack[top+2] = sexp_make_integer(fp);
top += 3;
bc = sexp_procedure_code(tmp1);
ip = sexp_bytecode_data(bc);
cp = sexp_procedure_vars(tmp1);
fp = top-4;
break;
case OP_FCALL0:
_PUSH(((sexp_proc0)_UWORD0)());
ip += sizeof(sexp);
sexp_check_exception();
break;
case OP_FCALL1:
_ARG1 = ((sexp_proc1)_UWORD0)(_ARG1);
ip += sizeof(sexp);
sexp_check_exception();
break;
case OP_FCALL2:
_ARG2 = ((sexp_proc2)_UWORD0)(_ARG1, _ARG2);
top--;
ip += sizeof(sexp);
sexp_check_exception();
break;
case OP_FCALL3:
_ARG3 =((sexp_proc3)_UWORD0)(_ARG1, _ARG2, _ARG3);
top -= 2;
ip += sizeof(sexp);
sexp_check_exception();
break;
case OP_FCALL4:
_ARG4 =((sexp_proc4)_UWORD0)(_ARG1, _ARG2, _ARG3, _ARG4);
top -= 3;
ip += sizeof(sexp);
sexp_check_exception();
break;
case OP_EVAL:
sexp_context_top(context) = top;
_ARG1 = eval_in_context(_ARG1, context);
sexp_check_exception();
break;
case OP_JUMP_UNLESS:
if (stack[--top] == SEXP_FALSE)
ip += _SWORD0;
else
ip += sizeof(sexp_sint_t);
break;
case OP_JUMP:
ip += _SWORD0;
break;
case OP_PUSH:
_PUSH(_WORD0);
ip += sizeof(sexp);
break;
case OP_DROP:
top--;
break;
case OP_GLOBAL_REF:
if (sexp_cdr(_WORD0) == SEXP_UNDEF)
sexp_raise("undefined variable", sexp_list1(sexp_car(_WORD0)));
/* ... FALLTHROUGH ... */
case OP_GLOBAL_KNOWN_REF:
_PUSH(sexp_cdr(_WORD0));
ip += sizeof(sexp);
break;
case OP_STACK_REF: /* `pick' in forth */
stack[top] = stack[top - _SWORD0];
ip += sizeof(sexp);
top++;
break;
case OP_LOCAL_REF:
stack[top] = stack[fp - 1 - _SWORD0];
ip += sizeof(sexp);
top++;
break;
case OP_LOCAL_SET:
stack[fp - 1 - _SWORD0] = _ARG1;
_ARG1 = SEXP_VOID;
ip += sizeof(sexp);
break;
case OP_CLOSURE_REF:
_PUSH(sexp_vector_ref(cp, sexp_make_integer(_WORD0)));
ip += sizeof(sexp);
break;
case OP_VECTOR_REF:
if (! sexp_vectorp(_ARG1))
sexp_raise("vector-ref: not a vector", sexp_list1(_ARG1));
_ARG2 = sexp_vector_ref(_ARG1, _ARG2);
top--;
break;
case OP_VECTOR_SET:
if (! sexp_vectorp(_ARG1))
sexp_raise("vector-set!: not a vector", sexp_list1(_ARG1));
sexp_vector_set(_ARG1, _ARG2, _ARG3);
_ARG3 = SEXP_VOID;
top-=2;
break;
case OP_VECTOR_LENGTH:
_ARG1 = sexp_make_integer(sexp_vector_length(_ARG1));
break;
case OP_STRING_REF:
_ARG2 = sexp_string_ref(_ARG1, _ARG2);
top--;
break;
case OP_STRING_SET:
sexp_string_set(_ARG1, _ARG2, _ARG3);
_ARG3 = SEXP_VOID;
top-=2;
break;
case OP_STRING_LENGTH:
_ARG1 = sexp_make_integer(sexp_string_length(_ARG1));
break;
case OP_MAKE_PROCEDURE:
_ARG4 = sexp_make_procedure(_ARG1, _ARG2, _ARG3, _ARG4);
top-=3;
break;
case OP_MAKE_VECTOR:
_ARG2 = sexp_make_vector(_ARG1, _ARG2);
top--;
break;
case OP_AND:
_ARG2 = sexp_make_boolean((_ARG1 != SEXP_FALSE) && (_ARG2 != SEXP_FALSE));
top--;
break;
case OP_EOFP:
_ARG1 = sexp_make_boolean(_ARG1 == SEXP_EOF); break;
case OP_NULLP:
_ARG1 = sexp_make_boolean(sexp_nullp(_ARG1)); break;
case OP_INTEGERP:
_ARG1 = sexp_make_boolean(sexp_integerp(_ARG1)); break;
case OP_SYMBOLP:
_ARG1 = sexp_make_boolean(sexp_symbolp(_ARG1)); break;
case OP_CHARP:
_ARG1 = sexp_make_boolean(sexp_charp(_ARG1)); break;
case OP_TYPEP:
_ARG1 = sexp_make_boolean(sexp_pointerp(_ARG1)
&& (sexp_pointer_tag(_ARG1)
== _UWORD0));
ip += sizeof(sexp);
break;
case OP_CAR:
if (! sexp_pairp(_ARG1)) sexp_raise("car: not a pair", sexp_list1(_ARG1));
_ARG1 = sexp_car(_ARG1); break;
case OP_CDR:
if (! sexp_pairp(_ARG1)) sexp_raise("cdr: not a pair", sexp_list1(_ARG1));
_ARG1 = sexp_cdr(_ARG1); break;
case OP_SET_CAR:
if (! sexp_pairp(_ARG1))
sexp_raise("set-car!: not a pair", sexp_list1(_ARG1));
sexp_car(_ARG1) = _ARG2;
_ARG2 = SEXP_VOID;
top--;
break;
case OP_SET_CDR:
if (! sexp_pairp(_ARG1))
sexp_raise("set-cdr!: not a pair", sexp_list1(_ARG1));
sexp_cdr(_ARG1) = _ARG2;
_ARG2 = SEXP_VOID;
top--;
break;
case OP_CONS:
_ARG2 = sexp_cons(_ARG1, _ARG2);
top--;
break;
case OP_ADD:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fx_add(_ARG1, _ARG2);
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_add(_ARG1, _ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fp_add(_ARG1, sexp_integer_to_flonum(_ARG2));
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_add(sexp_integer_to_flonum(_ARG1), _ARG2);
#endif
else sexp_raise("+: not a number", sexp_list2(_ARG1, _ARG2));
top--;
break;
case OP_SUB:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fx_sub(_ARG1, _ARG2);
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_sub(_ARG1, _ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fp_sub(_ARG1, sexp_integer_to_flonum(_ARG2));
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_sub(sexp_integer_to_flonum(_ARG1), _ARG2);
#endif
else sexp_raise("-: not a number", sexp_list2(_ARG1, _ARG2));
top--;
break;
case OP_MUL:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fx_mul(_ARG1, _ARG2);
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_mul(_ARG1, _ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fp_mul(_ARG1, sexp_integer_to_flonum(_ARG2));
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_mul(sexp_integer_to_flonum(_ARG1), _ARG2);
#endif
else sexp_raise("*: not a number", sexp_list2(_ARG1, _ARG2));
top--;
break;
case OP_DIV:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fp_div(sexp_integer_to_flonum(_ARG1),
sexp_integer_to_flonum(_ARG2));
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_div(_ARG1, _ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
_ARG2 = sexp_fp_div(_ARG1, sexp_integer_to_flonum(_ARG2));
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
_ARG2 = sexp_fp_div(sexp_integer_to_flonum(_ARG1), _ARG2);
#endif
else sexp_raise("/: not a number", sexp_list2(_ARG1, _ARG2));
top--;
break;
case OP_QUOTIENT:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2)) {
if (_ARG1 == sexp_make_integer(0))
sexp_raise("divide by zero", SEXP_NULL);
_ARG2 = sexp_fx_div(_ARG1, _ARG2);
top--;
}
else sexp_raise("quotient: not an integer", sexp_list2(_ARG1, _ARG2));
break;
case OP_REMAINDER:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2)) {
if (_ARG1 == sexp_make_integer(0))
sexp_raise("divide by zero", SEXP_NULL);
tmp1 = sexp_fx_rem(_ARG1, _ARG2);
top--;
_ARG1 = tmp1;
}
else sexp_raise("remainder: not an integer", sexp_list2(_ARG1, _ARG2));
break;
case OP_NEGATIVE:
if (sexp_integerp(_ARG1))
_ARG1 = sexp_make_integer(-sexp_unbox_integer(_ARG1));
#if USE_FLONUMS
else if (sexp_flonump(_ARG1))
_ARG1 = sexp_make_flonum(-sexp_flonum_value(_ARG1));
#endif
else sexp_raise("-: not a number", sexp_list1(_ARG1));
break;
case OP_INVERSE:
if (sexp_integerp(_ARG1))
_ARG1 = sexp_make_flonum(1/(double)sexp_unbox_integer(_ARG1));
#if USE_FLONUMS
else if (sexp_flonump(_ARG1))
_ARG1 = sexp_make_flonum(1/sexp_flonum_value(_ARG1));
#endif
else sexp_raise("/: not a number", sexp_list1(_ARG1));
break;
case OP_LT:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
i = _ARG1 < _ARG2;
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
i = sexp_flonum_value(_ARG1) < sexp_flonum_value(_ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
i = sexp_flonum_value(_ARG1) < (double)sexp_unbox_integer(_ARG2);
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
i = (double)sexp_unbox_integer(_ARG1) < sexp_flonum_value(_ARG2);
#endif
else sexp_raise("<: not a number", sexp_list2(_ARG1, _ARG2));
_ARG2 = sexp_make_boolean(i);
top--;
break;
case OP_LE:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
i = _ARG1 <= _ARG2;
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
i = sexp_flonum_value(_ARG1) <= sexp_flonum_value(_ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
i = sexp_flonum_value(_ARG1) <= (double)sexp_unbox_integer(_ARG2);
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
i = (double)sexp_unbox_integer(_ARG1) <= sexp_flonum_value(_ARG2);
#endif
else sexp_raise("<=: not a number", sexp_list2(_ARG1, _ARG2));
_ARG2 = sexp_make_boolean(i);
top--;
break;
case OP_EQN:
if (sexp_integerp(_ARG1) && sexp_integerp(_ARG2))
i = _ARG1 == _ARG2;
#if USE_FLONUMS
else if (sexp_flonump(_ARG1) && sexp_flonump(_ARG2))
i = sexp_flonum_value(_ARG1) == sexp_flonum_value(_ARG2);
else if (sexp_flonump(_ARG1) && sexp_integerp(_ARG2))
i = sexp_flonum_value(_ARG1) == (double)sexp_unbox_integer(_ARG2);
else if (sexp_integerp(_ARG1) && sexp_flonump(_ARG2))
i = (double)sexp_unbox_integer(_ARG1) == sexp_flonum_value(_ARG2);
#endif
else sexp_raise("=: not a number", sexp_list2(_ARG1, _ARG2));
_ARG2 = sexp_make_boolean(i);
top--;
break;
case OP_EQ:
_ARG2 = sexp_make_boolean(_ARG1 == _ARG2);
top--;
break;
case OP_FIX2FLO:
if (sexp_integerp(_ARG1))
_ARG1 = sexp_integer_to_flonum(_ARG1);
else
#if USE_FLONUMS
if (! sexp_flonump(_ARG1))
#endif
sexp_raise("exact->inexact: not a number", sexp_list1(_ARG1));
break;
case OP_FLO2FIX:
#if USE_FLONUMS
if (sexp_flonump(_ARG1))
_ARG1 = sexp_make_integer((sexp_sint_t)sexp_flonum_value(_ARG1));
else
#endif
if (! sexp_integerp(_ARG1))
sexp_raise("inexact->exact: not a number", sexp_list1(_ARG1));
break;
case OP_CHAR2INT:
_ARG1 = sexp_make_integer(sexp_unbox_character(_ARG1));
break;
case OP_INT2CHAR:
_ARG1 = sexp_make_character(sexp_unbox_integer(_ARG1));
break;
case OP_CHAR_UPCASE:
_ARG1 = sexp_make_character(toupper(sexp_unbox_character(_ARG1)));
break;
case OP_CHAR_DOWNCASE:
_ARG1 = sexp_make_character(tolower(sexp_unbox_character(_ARG1)));
break;
case OP_DISPLAY:
if (sexp_stringp(_ARG1)) {
sexp_write_string(sexp_string_data(_ARG1), _ARG2);
_ARG2 = SEXP_VOID;
top--;
break;
} else if (sexp_charp(_ARG1)) {
sexp_write_char(sexp_unbox_character(_ARG1), _ARG2);
_ARG2 = SEXP_VOID;
top--;
break;
}
/* ... FALLTHROUGH ... */
case OP_WRITE:
sexp_write(_ARG1, _ARG2);
_ARG2 = SEXP_VOID;
top--;
break;
case OP_WRITE_CHAR:
sexp_write_char(sexp_unbox_character(_ARG1), _ARG2);
_ARG2 = SEXP_VOID;
top--;
break;
case OP_NEWLINE:
sexp_write_char('\n', _ARG1);
_ARG1 = SEXP_VOID;
break;
case OP_FLUSH_OUTPUT:
sexp_flush(_ARG1);
_ARG1 = SEXP_VOID;
break;
case OP_READ:
_ARG1 = sexp_read(_ARG1);
sexp_check_exception();
break;
case OP_READ_CHAR:
i = sexp_read_char(_ARG1);
_ARG1 = (i == EOF) ? SEXP_EOF : sexp_make_character(i);
break;
case OP_PEEK_CHAR:
i = sexp_read_char(_ARG1);
sexp_push_char(i, _ARG1);
_ARG1 = (i == EOF) ? SEXP_EOF : sexp_make_character(i);
break;
case OP_RET:
i = sexp_unbox_integer(stack[fp]);
stack[fp-i] = _ARG1;
top = fp-i+1;
ip = (unsigned char*) sexp_unbox_integer(stack[fp+1]);
cp = stack[fp+2];
fp = sexp_unbox_integer(stack[fp+3]);
break;
case OP_DONE:
goto end_loop;
default:
sexp_raise("unknown opcode", sexp_list1(sexp_make_integer(*(ip-1))));
}
goto loop;
end_loop:
return _ARG1;
}
/************************ library procedures **************************/
sexp sexp_open_input_file (sexp path) {
return sexp_make_input_port(fopen(sexp_string_data(path), "r"));
}
sexp sexp_open_output_file (sexp path) {
return sexp_make_input_port(fopen(sexp_string_data(path), "w"));
}
sexp sexp_close_port (sexp port) {
fclose(sexp_port_stream(port));
return SEXP_VOID;
}
sexp sexp_load (sexp source, sexp env) {
sexp obj, res, in, context = sexp_make_context(NULL, env);
in = sexp_open_input_file(source);
while ((obj=sexp_read(in)) != (sexp) SEXP_EOF) {
res = eval_in_context(obj, context);
if (sexp_exceptionp(res))
break;
}
if (obj == SEXP_EOF)
res = SEXP_VOID;
sexp_close_port(in);
return res;
}
#if USE_MATH
#define define_math_op(name, cname) \
static sexp name (sexp z) { \
double d; \
if (sexp_flonump(z)) \
d = sexp_flonum_value(z); \
else if (sexp_integerp(z)) \
d = (double)sexp_unbox_integer(z); \
else \
return sexp_type_exception("not a number", z); \
return sexp_make_flonum(cname(d)); \
}
define_math_op(sexp_exp, exp)
define_math_op(sexp_log, log)
define_math_op(sexp_sin, sin)
define_math_op(sexp_cos, cos)
define_math_op(sexp_tan, tan)
define_math_op(sexp_asin, asin)
define_math_op(sexp_acos, acos)
define_math_op(sexp_atan, atan)
define_math_op(sexp_sqrt, sqrt)
define_math_op(sexp_round, round)
define_math_op(sexp_trunc, trunc)
define_math_op(sexp_floor, floor)
define_math_op(sexp_ceiling, ceil)
#endif
static sexp sexp_expt (sexp x, sexp e) {
double res, x1, e1;
if (sexp_integerp(x))
x1 = (double)sexp_unbox_integer(x);
#if USE_FLONUMS
else if (sexp_flonump(x))
x1 = sexp_flonum_value(x);
#endif
else
return sexp_type_exception("not a number", x);
if (sexp_integerp(e))
e1 = (double)sexp_unbox_integer(e);
#if USE_FLONUMS
else if (sexp_flonump(e))
e1 = sexp_flonum_value(e);
#endif
else
return sexp_type_exception("not a number", e);
res = pow(x1, e1);
#if USE_FLONUMS
if ((res > SEXP_MAX_INT) || sexp_flonump(x) || sexp_flonump(e))
return sexp_make_flonum(res);
#endif
return sexp_make_integer((sexp_sint_t)round(res));
}
static sexp sexp_string_concatenate (sexp str_ls) {
sexp res, ls;
sexp_uint_t len=0;
char *p;
for (ls=str_ls; sexp_pairp(ls); ls=sexp_cdr(ls))
if (! sexp_stringp(sexp_car(ls)))
return sexp_type_exception("not a string", sexp_car(ls));
else
len += sexp_string_length(sexp_car(ls));
res = sexp_make_string(sexp_make_integer(len), SEXP_VOID);
p = sexp_string_data(res);
for (ls=str_ls; sexp_pairp(ls); ls=sexp_cdr(ls)) {
len = sexp_string_length(sexp_car(ls));
memcpy(p, sexp_string_data(sexp_car(ls)), len);
p += len;
}
return res;
}
static sexp sexp_string_cmp (sexp str1, sexp str2) {
sexp_sint_t len1, len2, len, diff;
if (! sexp_stringp(str1))
return sexp_type_exception("not a string", str1);
if (! sexp_stringp(str2))
return sexp_type_exception("not a string", str2);
len1 = sexp_string_length(str1);
len2 = sexp_string_length(str2);
len = ((len1<len2) ? len1 : len2);
diff = strncmp(sexp_string_data(str1), sexp_string_data(str2), len);
if (! diff)
diff = len1 - len2;
return sexp_make_integer(diff);
}
static sexp sexp_string_cmp_ci (sexp str1, sexp str2) {
sexp_sint_t len1, len2, len, diff;
if (! sexp_stringp(str1))
return sexp_type_exception("not a string", str1);
if (! sexp_stringp(str2))
return sexp_type_exception("not a string", str2);
len1 = sexp_string_length(str1);
len2 = sexp_string_length(str2);
len = ((len1<len2) ? len1 : len2);
diff = strncasecmp(sexp_string_data(str1), sexp_string_data(str2), len);
if (! diff)
diff = len1 - len2;
return sexp_make_integer(diff);
}
/*********************** standard environment *************************/
static struct sexp_struct core_forms[] = {
{.tag=SEXP_CORE, .value={.core={CORE_DEFINE, "define"}}},
{.tag=SEXP_CORE, .value={.core={CORE_SET, "set!"}}},
{.tag=SEXP_CORE, .value={.core={CORE_LAMBDA, "lambda"}}},
{.tag=SEXP_CORE, .value={.core={CORE_IF, "if"}}},
{.tag=SEXP_CORE, .value={.core={CORE_BEGIN, "begin"}}},
{.tag=SEXP_CORE, .value={.core={CORE_QUOTE, "quote"}}},
{.tag=SEXP_CORE, .value={.core={CORE_DEFINE_SYNTAX, "define-syntax"}}},
{.tag=SEXP_CORE, .value={.core={CORE_LET_SYNTAX, "let-syntax"}}},
{.tag=SEXP_CORE, .value={.core={CORE_LETREC_SYNTAX, "letrec-syntax"}}},
};
#include "opcodes.c"
static int standard_env_syms_interned_p = 0;
static sexp sexp_make_null_env (sexp version) {
sexp_uint_t i;
sexp e = sexp_alloc_type(env, SEXP_ENV);
sexp_env_parent(e) = NULL;
sexp_env_bindings(e) = SEXP_NULL;
for (i=0; i<(sizeof(core_forms)/sizeof(core_forms[0])); i++)
env_define(e, sexp_intern(sexp_core_name(&core_forms[i])), &core_forms[i]);
return e;
}
static sexp sexp_make_standard_env (sexp version) {
sexp_uint_t i;
sexp e = sexp_make_null_env(version), op, cell, sym;
for (i=0; i<(sizeof(opcodes)/sizeof(opcodes[0])); i++) {
op = &opcodes[i];
if ((! standard_env_syms_interned_p)
&& sexp_opcode_opt_param_p(op)
&& sexp_opcode_default(op)) {
sym = sexp_intern((char*)sexp_opcode_default(op));
cell = env_cell_create(e, sym, SEXP_VOID);
sexp_opcode_default(op) = cell;
}
env_define(e, sexp_intern(sexp_opcode_name(op)), op);
}
env_define(e, the_cur_in_symbol, sexp_make_input_port(stdin));
env_define(e, the_cur_out_symbol, sexp_make_output_port(stdout));
env_define(e, the_cur_err_symbol, sexp_make_output_port(stderr));
env_define(e, the_interaction_env_symbol, e);
standard_env_syms_interned_p = 1;
return e;
}
/************************** eval interface ****************************/
sexp apply(sexp proc, sexp args, sexp context) {
sexp *stack = sexp_context_stack(context), ls;
sexp_sint_t top = sexp_context_top(context), offset;
offset = top + sexp_unbox_integer(sexp_length(args));
for (ls=args; sexp_pairp(ls); ls=sexp_cdr(ls), top++)
stack[--offset] = sexp_car(ls);
stack[top] = sexp_make_integer(top);
top++;
stack[top++] = sexp_make_integer(sexp_bytecode_data(final_resumer));
stack[top++] = sexp_make_vector(0, SEXP_VOID);
stack[top++] = sexp_make_integer(0);
return vm(sexp_procedure_code(proc),
sexp_procedure_vars(proc),
context,
stack,
top);
}
sexp compile (sexp x, sexp context) {
sexp ast, ctx;
analyze_bind(ast, x, context);
free_vars(ast, SEXP_NULL); /* should return SEXP_NULL */
ctx = sexp_make_context(sexp_context_stack(context),
sexp_context_env(context));
generate(ast, ctx);
return sexp_make_procedure(sexp_make_integer(0),
sexp_make_integer(0),
finalize_bytecode(ctx),
sexp_make_vector(0, SEXP_VOID));
}
sexp eval_in_context (sexp obj, sexp context) {
sexp thunk = compile(obj, context);
if (sexp_exceptionp(thunk)) {
sexp_print_exception(thunk, env_global_ref(sexp_context_env(context),
the_cur_err_symbol,
SEXP_FALSE));
return SEXP_VOID;
}
return apply(thunk, SEXP_NULL, context);
}
sexp eval (sexp obj, sexp env) {
sexp context = sexp_make_context(NULL, NULL);
sexp_context_env(context) = env;
return eval_in_context(obj, context);
}
void scheme_init () {
sexp context;
if (! scheme_initialized_p) {
scheme_initialized_p = 1;
sexp_init();
the_compile_error_symbol = sexp_intern("compile-error");
the_err_handler_symbol = sexp_intern("*current-error-handler*");
the_cur_in_symbol = sexp_intern("*current-input-port*");
the_cur_out_symbol = sexp_intern("*current-output-port*");
the_cur_err_symbol = sexp_intern("*current-error-port*");
the_interaction_env_symbol = sexp_intern("*interaction-environment*");
#if USE_BOEHM
GC_add_roots((char*)&continuation_resumer,
((char*)&continuation_resumer)+sizeof(continuation_resumer)+1);
GC_add_roots((char*)&final_resumer,
((char*)&final_resumer)+sizeof(continuation_resumer)+1);
GC_add_roots((char*)&opcodes, ((char*)&opcodes)+sizeof(opcodes)+1);
#endif
context = sexp_make_context(NULL, NULL);
emit(OP_RESUMECC, context);
continuation_resumer = finalize_bytecode(context);
context = sexp_child_context(context, NULL);
emit(OP_DONE, context);
final_resumer = finalize_bytecode(context);
}
}