ref: c42ee12d4cbbf57cdefd27cb4b881e185030d60d
dir: /femtolisp/flisp.c/
/*
femtoLisp
a minimal interpreter for a minimal lisp dialect
this lisp dialect uses lexical scope and self-evaluating lambda.
it supports 30-bit integers, symbols, conses, and full macros.
it is case-sensitive.
it features a simple compacting copying garbage collector.
it uses a Scheme-style evaluation rule where any expression may appear in
head position as long as it evaluates to a function.
it uses Scheme-style varargs (dotted formal argument lists)
lambdas can have only 1 body expression; use (begin ...) for multiple
expressions. this is due to the closure representation
(lambda args body . env)
This is a fully fleshed-out lisp built up from femtoLisp. It has all the
remaining features needed to be taken seriously:
* circular structure can be printed and read
* #. read macro for eval-when-read and correctly printing builtins
* read macros for backquote
* symbol character-escaping printer
* vectors
* exceptions
* gensyms (can be usefully read back in, too)
* #| multiline comments |#
* generic compare function, cyclic equal
* cvalues system providing C data types and a C FFI
* constructor notation for nicely printing arbitrary values
* strings
* hash tables
* I/O streams
by Jeff Bezanson (C) 2009
Distributed under the BSD License
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <setjmp.h>
#include <stdarg.h>
#include <assert.h>
#include <ctype.h>
#include <wctype.h>
#include <sys/types.h>
#include <locale.h>
#include <limits.h>
#include <errno.h>
#include <math.h>
#include "llt.h"
#include "flisp.h"
#include "opcodes.h"
static char *builtin_names[] =
{ NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
// predicates
"eq?", "eqv?", "equal?", "atom?", "not", "null?", "boolean?", "symbol?",
"number?", "bound?", "pair?", "builtin?", "vector?", "fixnum?",
"function?",
// lists
"cons", "list", "car", "cdr", "set-car!", "set-cdr!",
// execution
"apply",
// arithmetic
"+", "-", "*", "/", "div0", "=", "<", "compare",
// sequences
"vector", "aref", "aset!",
"", "", "" };
#define ANYARGS -10000
static short builtin_arg_counts[] =
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
2, ANYARGS, 1, 1, 2, 2,
-2,
ANYARGS, -1, ANYARGS, -1, 2, 2, 2, 2,
ANYARGS, 2, 3 };
#define N_STACK 262144
static value_t Stack[N_STACK];
static uint32_t SP = 0;
#define PUSH(v) (Stack[SP++] = (v))
#define POP() (Stack[--SP])
#define POPN(n) (SP-=(n))
#define N_GC_HANDLES 1024
static value_t *GCHandleStack[N_GC_HANDLES];
static uint32_t N_GCHND = 0;
value_t NIL, FL_T, FL_F, LAMBDA, QUOTE, IF, TRYCATCH;
value_t BACKQUOTE, COMMA, COMMAAT, COMMADOT, FUNCTION;
value_t IOError, ParseError, TypeError, ArgError, UnboundError, MemoryError;
value_t DivideError, BoundsError, Error, KeyError, EnumerationError;
value_t conssym, symbolsym, fixnumsym, vectorsym, builtinsym, vu8sym;
value_t definesym, defmacrosym, forsym, labelsym, printprettysym, setqsym;
value_t printwidthsym, printreadablysym;
value_t tsym, Tsym, fsym, Fsym, booleansym, nullsym, evalsym;
static value_t apply_cl(uint32_t nargs);
static value_t *alloc_words(int n);
static value_t relocate(value_t v);
typedef struct _readstate_t {
htable_t backrefs;
htable_t gensyms;
value_t source;
struct _readstate_t *prev;
} readstate_t;
static readstate_t *readstate = NULL;
static void free_readstate(readstate_t *rs)
{
htable_free(&rs->backrefs);
htable_free(&rs->gensyms);
}
static unsigned char *fromspace;
static unsigned char *tospace;
static unsigned char *curheap;
static unsigned char *lim;
static uint32_t heapsize = 512*1024;//bytes
static uint32_t *consflags;
// error utilities ------------------------------------------------------------
// saved execution state for an unwind target
typedef struct _ectx_t {
jmp_buf buf;
uint32_t sp;
readstate_t *rdst;
struct _ectx_t *prev;
} exception_context_t;
static exception_context_t *ctx = NULL;
static value_t lasterror;
#define FL_TRY \
exception_context_t _ctx; int l__tr, l__ca; \
_ctx.sp=SP; _ctx.rdst=readstate; _ctx.prev=ctx; \
ctx = &_ctx; \
if (!setjmp(_ctx.buf)) \
for (l__tr=1; l__tr; l__tr=0, (void)(ctx->prev && (ctx=ctx->prev)))
#define FL_CATCH \
else \
for (l__ca=1; l__ca; l__ca=0, lasterror=NIL)
void raise(value_t e)
{
lasterror = e;
// unwind read state
while (readstate != ctx->rdst) {
free_readstate(readstate);
readstate = readstate->prev;
}
SP = ctx->sp;
exception_context_t *thisctx = ctx;
if (ctx->prev) // don't throw past toplevel
ctx = ctx->prev;
longjmp(thisctx->buf, 1);
}
static value_t make_error_msg(char *format, va_list args)
{
char msgbuf[512];
vsnprintf(msgbuf, sizeof(msgbuf), format, args);
return string_from_cstr(msgbuf);
}
void lerrorf(value_t e, char *format, ...)
{
va_list args;
PUSH(e);
va_start(args, format);
value_t msg = make_error_msg(format, args);
va_end(args);
e = POP();
raise(list2(e, msg));
}
void lerror(value_t e, const char *msg)
{
PUSH(e);
value_t m = cvalue_static_cstring(msg);
e = POP();
raise(list2(e, m));
}
void type_error(char *fname, char *expected, value_t got)
{
raise(listn(4, TypeError, symbol(fname), symbol(expected), got));
}
void bounds_error(char *fname, value_t arr, value_t ind)
{
lerrorf(listn(3, BoundsError, arr, ind), "%s: index out of bounds", fname);
}
// safe cast operators --------------------------------------------------------
#define SAFECAST_OP(type,ctype,cnvt) \
ctype to##type(value_t v, char *fname) \
{ \
if (is##type(v)) \
return (ctype)cnvt(v); \
type_error(fname, #type, v); \
}
SAFECAST_OP(cons, cons_t*, ptr)
SAFECAST_OP(symbol,symbol_t*,ptr)
SAFECAST_OP(fixnum,fixnum_t, numval)
SAFECAST_OP(cvalue,cvalue_t*,ptr)
SAFECAST_OP(string,char*, cvalue_data)
// symbol table ---------------------------------------------------------------
symbol_t *symtab = NULL;
static symbol_t *mk_symbol(char *str)
{
symbol_t *sym;
size_t len = strlen(str);
sym = (symbol_t*)malloc(sizeof(symbol_t)-sizeof(void*) + len + 1);
assert(((uptrint_t)sym & 0x7) == 0); // make sure malloc aligns 8
sym->left = sym->right = NULL;
if (str[0] == ':') {
value_t s = tagptr(sym, TAG_SYM);
setc(s, s);
}
else {
sym->binding = UNBOUND;
sym->syntax = 0;
}
sym->type = sym->dlcache = NULL;
sym->hash = memhash32(str, len)^0xAAAAAAAA;
strcpy(&sym->name[0], str);
return sym;
}
static symbol_t **symtab_lookup(symbol_t **ptree, char *str)
{
int x;
while(*ptree != NULL) {
x = strcmp(str, (*ptree)->name);
if (x == 0)
return ptree;
if (x < 0)
ptree = &(*ptree)->left;
else
ptree = &(*ptree)->right;
}
return ptree;
}
value_t symbol(char *str)
{
symbol_t **pnode;
pnode = symtab_lookup(&symtab, str);
if (*pnode == NULL)
*pnode = mk_symbol(str);
return tagptr(*pnode, TAG_SYM);
}
typedef struct {
value_t syntax; // syntax environment entry
value_t binding; // global value binding
fltype_t *type;
uint32_t id;
} gensym_t;
static uint32_t _gensym_ctr=0;
// two static buffers for gensym printing so there can be two
// gensym names available at a time, mostly for compare()
static char gsname[2][16];
static int gsnameno=0;
value_t fl_gensym(value_t *args, uint32_t nargs)
{
argcount("gensym", nargs, 0);
(void)args;
gensym_t *gs = (gensym_t*)alloc_words(sizeof(gensym_t)/sizeof(void*));
gs->id = _gensym_ctr++;
gs->binding = UNBOUND;
gs->syntax = 0;
gs->type = NULL;
return tagptr(gs, TAG_SYM);
}
char *symbol_name(value_t v)
{
if (ismanaged(v)) {
gensym_t *gs = (gensym_t*)ptr(v);
gsnameno = 1-gsnameno;
char *n = uint2str(gsname[gsnameno]+1, sizeof(gsname[0])-1, gs->id, 10);
*(--n) = 'g';
return n;
}
return ((symbol_t*)ptr(v))->name;
}
// conses ---------------------------------------------------------------------
void gc(int mustgrow);
static value_t mk_cons(void)
{
cons_t *c;
if (__unlikely(curheap > lim))
gc(0);
c = (cons_t*)curheap;
curheap += sizeof(cons_t);
return tagptr(c, TAG_CONS);
}
static value_t *alloc_words(int n)
{
value_t *first;
assert(n > 0);
n = ALIGN(n, 2); // only allocate multiples of 2 words
if (__unlikely((value_t*)curheap > ((value_t*)lim)+2-n)) {
gc(0);
while ((value_t*)curheap > ((value_t*)lim)+2-n) {
gc(1);
}
}
first = (value_t*)curheap;
curheap += (n*sizeof(value_t));
return first;
}
// allocate n consecutive conses
#define cons_reserve(n) tagptr(alloc_words((n)*2), TAG_CONS)
#define cons_index(c) (((cons_t*)ptr(c))-((cons_t*)fromspace))
#define ismarked(c) bitvector_get(consflags, cons_index(c))
#define mark_cons(c) bitvector_set(consflags, cons_index(c), 1)
#define unmark_cons(c) bitvector_set(consflags, cons_index(c), 0)
static value_t the_empty_vector;
value_t alloc_vector(size_t n, int init)
{
if (n == 0) return the_empty_vector;
value_t *c = alloc_words(n+1);
value_t v = tagptr(c, TAG_VECTOR);
vector_setsize(v, n);
if (init) {
unsigned int i;
for(i=0; i < n; i++)
vector_elt(v, i) = NIL;
}
return v;
}
// cvalues --------------------------------------------------------------------
#include "cvalues.c"
#include "types.c"
// print ----------------------------------------------------------------------
static int isnumtok(char *tok, value_t *pval);
static int symchar(char c);
#include "print.c"
// collector ------------------------------------------------------------------
void fl_gc_handle(value_t *pv)
{
if (N_GCHND >= N_GC_HANDLES)
lerror(MemoryError, "out of gc handles");
GCHandleStack[N_GCHND++] = pv;
}
void fl_free_gc_handles(int n)
{
assert(N_GCHND >= n);
N_GCHND -= n;
}
static value_t relocate(value_t v)
{
value_t a, d, nc, first, *pcdr;
uptrint_t t = tag(v);
if (t == TAG_CONS) {
// iterative implementation allows arbitrarily long cons chains
pcdr = &first;
do {
if ((a=car_(v)) == TAG_FWD) {
*pcdr = cdr_(v);
return first;
}
*pcdr = nc = mk_cons();
d = cdr_(v);
car_(v) = TAG_FWD; cdr_(v) = nc;
car_(nc) = relocate(a);
pcdr = &cdr_(nc);
v = d;
} while (iscons(v));
*pcdr = (d==NIL) ? NIL : relocate(d);
return first;
}
if ((t&3) == 0) return v;
if (!ismanaged(v)) return v;
if (isforwarded(v)) return forwardloc(v);
if (t == TAG_VECTOR) {
// N.B.: 0-length vectors secretly have space for a first element
size_t i, sz = vector_size(v);
if (vector_elt(v,-1) & 0x1) {
// grown vector
nc = relocate(vector_elt(v,0));
forward(v, nc);
}
else {
nc = tagptr(alloc_words(sz+1), TAG_VECTOR);
vector_setsize(nc, sz);
a = vector_elt(v,0);
forward(v, nc);
if (sz > 0) {
vector_elt(nc,0) = relocate(a);
for(i=1; i < sz; i++)
vector_elt(nc,i) = relocate(vector_elt(v,i));
}
}
return nc;
}
else if (t == TAG_CPRIM) {
cprim_t *pcp = (cprim_t*)ptr(v);
size_t nw = CPRIM_NWORDS-1+NWORDS(cp_class(pcp)->size);
cprim_t *ncp = (cprim_t*)alloc_words(nw);
while (nw--)
((value_t*)ncp)[nw] = ((value_t*)pcp)[nw];
nc = tagptr(ncp, TAG_CPRIM);
forward(v, nc);
return nc;
}
else if (t == TAG_CVALUE) {
return cvalue_relocate(v);
}
else if (t == TAG_FUNCTION) {
function_t *fn = (function_t*)ptr(v);
function_t *nfn = (function_t*)alloc_words(4);
nfn->bcode = fn->bcode;
nfn->vals = fn->vals;
nc = tagptr(nfn, TAG_FUNCTION);
forward(v, nc);
nfn->env = relocate(fn->env);
nfn->vals = relocate(nfn->vals);
nfn->bcode = relocate(nfn->bcode);
return nc;
}
else if (t == TAG_SYM) {
gensym_t *gs = (gensym_t*)ptr(v);
gensym_t *ng = (gensym_t*)alloc_words(sizeof(gensym_t)/sizeof(void*));
ng->id = gs->id;
ng->binding = gs->binding;
ng->syntax = gs->syntax;
nc = tagptr(ng, TAG_SYM);
forward(v, nc);
if (ng->binding != UNBOUND)
ng->binding = relocate(ng->binding);
if (iscons(ng->syntax))
ng->syntax = relocate(ng->syntax);
return nc;
}
return v;
}
value_t relocate_lispvalue(value_t v)
{
return relocate(v);
}
static void trace_globals(symbol_t *root)
{
while (root != NULL) {
if (root->binding != UNBOUND)
root->binding = relocate(root->binding);
if (iscons(root->syntax) || iscvalue(root->syntax))
root->syntax = relocate(root->syntax);
trace_globals(root->left);
root = root->right;
}
}
static value_t memory_exception_value;
void gc(int mustgrow)
{
static int grew = 0;
void *temp;
uint32_t i;
readstate_t *rs;
curheap = tospace;
lim = curheap+heapsize-sizeof(cons_t);
for (i=0; i < SP; i++)
Stack[i] = relocate(Stack[i]);
for (i=0; i < N_GCHND; i++)
*GCHandleStack[i] = relocate(*GCHandleStack[i]);
trace_globals(symtab);
relocate_typetable();
rs = readstate;
while (rs) {
for(i=0; i < rs->backrefs.size; i++)
rs->backrefs.table[i] = (void*)relocate((value_t)rs->backrefs.table[i]);
for(i=0; i < rs->gensyms.size; i++)
rs->gensyms.table[i] = (void*)relocate((value_t)rs->gensyms.table[i]);
rs->source = relocate(rs->source);
rs = rs->prev;
}
lasterror = relocate(lasterror);
memory_exception_value = relocate(memory_exception_value);
the_empty_vector = relocate(the_empty_vector);
sweep_finalizers();
#ifdef VERBOSEGC
printf("GC: found %d/%d live conses\n",
(curheap-tospace)/sizeof(cons_t), heapsize/sizeof(cons_t));
#endif
temp = tospace;
tospace = fromspace;
fromspace = temp;
// if we're using > 80% of the space, resize tospace so we have
// more space to fill next time. if we grew tospace last time,
// grow the other half of the heap this time to catch up.
if (grew || ((lim-curheap) < (int)(heapsize/5)) || mustgrow) {
temp = realloc(tospace, grew ? heapsize : heapsize*2);
if (temp == NULL)
raise(memory_exception_value);
tospace = temp;
if (!grew) {
heapsize*=2;
}
else {
temp = bitvector_resize(consflags, heapsize/sizeof(cons_t), 1);
if (temp == NULL)
raise(memory_exception_value);
consflags = (uint32_t*)temp;
}
grew = !grew;
}
if (curheap > lim) // all data was live
gc(0);
}
// utils ----------------------------------------------------------------------
// apply function with n args on the stack
static value_t _applyn(uint32_t n)
{
value_t f = Stack[SP-n-1];
uint32_t saveSP = SP;
value_t v;
if (iscbuiltin(f)) {
v = ((builtin_t*)ptr(f))[3](&Stack[SP-n], n);
}
else if (isfunction(f)) {
v = apply_cl(n);
}
else {
type_error("apply", "function", f);
}
SP = saveSP;
return v;
}
value_t apply(value_t f, value_t l)
{
value_t v = l;
uint32_t n = SP;
PUSH(f);
while (iscons(v)) {
if ((SP-n-1) == MAX_ARGS) {
PUSH(v);
break;
}
PUSH(car_(v));
v = cdr_(v);
}
n = SP - n - 1;
assert(n <= MAX_ARGS+1);
v = _applyn(n);
POPN(n+1);
return v;
}
value_t applyn(uint32_t n, value_t f, ...)
{
va_list ap;
va_start(ap, f);
size_t i;
PUSH(f);
for(i=0; i < n; i++) {
value_t a = va_arg(ap, value_t);
PUSH(a);
}
value_t v = _applyn(n);
POPN(n+1);
return v;
}
value_t listn(size_t n, ...)
{
va_list ap;
va_start(ap, n);
uint32_t si = SP;
size_t i;
for(i=0; i < n; i++) {
value_t a = va_arg(ap, value_t);
PUSH(a);
}
cons_t *c = (cons_t*)alloc_words(n*2);
cons_t *l = c;
for(i=0; i < n; i++) {
c->car = Stack[si++];
c->cdr = tagptr(c+1, TAG_CONS);
c++;
}
(c-1)->cdr = NIL;
POPN(n);
va_end(ap);
return tagptr(l, TAG_CONS);
}
value_t list2(value_t a, value_t b)
{
PUSH(a);
PUSH(b);
cons_t *c = (cons_t*)alloc_words(4);
b = POP();
a = POP();
c[0].car = a;
c[0].cdr = tagptr(c+1, TAG_CONS);
c[1].car = b;
c[1].cdr = NIL;
return tagptr(c, TAG_CONS);
}
value_t fl_cons(value_t a, value_t b)
{
PUSH(a);
PUSH(b);
value_t c = mk_cons();
cdr_(c) = POP();
car_(c) = POP();
return c;
}
int isnumber(value_t v)
{
return (isfixnum(v) || iscprim(v));
}
// read -----------------------------------------------------------------------
#include "read.c"
// eval -----------------------------------------------------------------------
static value_t list(value_t *args, uint32_t nargs)
{
cons_t *c;
uint32_t i;
value_t v;
v = cons_reserve(nargs);
c = (cons_t*)ptr(v);
for(i=0; i < nargs; i++) {
c->car = args[i];
c->cdr = tagptr(c+1, TAG_CONS);
c++;
}
if (nargs > MAX_ARGS)
(c-2)->cdr = (c-1)->car;
else
(c-1)->cdr = NIL;
return v;
}
// perform (apply list* L)
// like the function list() above, but takes arguments from a list
// rather than from an array (the stack)
static value_t apply_liststar(value_t L)
{
PUSH(NIL);
PUSH(NIL);
PUSH(L);
value_t *pfirst = &Stack[SP-3];
value_t *plcons = &Stack[SP-2];
value_t *pL = &Stack[SP-1];
value_t c;
while (iscons(*pL)) {
if (iscons(cdr_(*pL))) {
c = mk_cons();
car_(c) = car_(*pL);
cdr_(c) = NIL;
}
else {
// last element; becomes final CDR
c = car_(*pL);
}
if (*pfirst == NIL)
*pfirst = c;
else
cdr_(*plcons) = c;
*plcons = c;
*pL = cdr_(*pL);
}
POPN(2);
return POP();
}
static value_t do_trycatch()
{
uint32_t saveSP = SP;
value_t v;
value_t thunk = Stack[SP-2];
Stack[SP-2] = Stack[SP-1];
Stack[SP-1] = thunk;
FL_TRY {
v = apply_cl(0);
}
FL_CATCH {
Stack[SP-1] = lasterror;
v = apply_cl(1);
}
SP = saveSP;
return v;
}
#define fn_bcode(f) (((value_t*)ptr(f))[0])
#define fn_vals(f) (((value_t*)ptr(f))[1])
#define fn_env(f) (((value_t*)ptr(f))[2])
/*
stack on entry: <func> <args...>
caller's responsibility:
- put the stack in this state
- provide arg count
- respect tail position
- restore SP
callee's responsibility:
- check arg counts
- allocate vararg array
- push closed env, set up new environment
*/
static value_t apply_cl(uint32_t nargs)
{
// frame variables
uint32_t i, n, ip, bp, captured;
fixnum_t s, hi;
uint8_t *code;
// temporary variables (not necessary to preserve across calls)
uint32_t op, envsz;
int64_t accum;
symbol_t *sym;
cons_t *c;
value_t func, v, x, e;
value_t *lenv, *pv;
apply_cl_top:
captured = 0;
func = Stack[SP-nargs-1];
code = cv_data((cvalue_t*)ptr(fn_bcode(func)));
assert(!ismanaged((uptrint_t)code));
assert(ismanaged(func));
bp = SP-nargs;
PUSH(fn_env(func));
ip = 0;
{
next_op:
op = code[ip++];
dispatch:
switch (op) {
case OP_ARGC:
n = code[ip++];
if (nargs != n) {
if (nargs > n)
lerror(ArgError, "apply: too many arguments");
else
lerror(ArgError, "apply: too few arguments");
}
goto next_op;
case OP_VARGC:
i = code[ip++];
s = (fixnum_t)nargs - (fixnum_t)i;
v = NIL;
if (s > 0) {
v = list(&Stack[bp+i], s);
if (nargs > MAX_ARGS) {
c = (cons_t*)curheap;
(c-2)->cdr = (c-1)->car;
}
Stack[bp+i] = v;
Stack[bp+i+1] = Stack[bp+nargs];
}
else if (s < 0) {
lerror(ArgError, "apply: too few arguments");
}
else {
PUSH(NIL);
Stack[SP-1] = Stack[SP-2];
Stack[SP-2] = NIL;
}
nargs = i+1;
goto next_op;
case OP_LET:
// last arg is closure environment to use
nargs--;
POPN(1);
goto next_op;
case OP_NOP: goto next_op;
case OP_DUP: SP++; Stack[SP-1] = Stack[SP-2]; goto next_op;
case OP_POP: POPN(1); goto next_op;
case OP_TCALL:
n = code[ip++]; // nargs
do_tcall:
if (isfunction(Stack[SP-n-1])) {
for(s=-1; s < (fixnum_t)n; s++)
Stack[bp+s] = Stack[SP-n+s];
SP = bp+n;
nargs = n;
goto apply_cl_top;
}
goto do_call;
case OP_CALL:
n = code[ip++]; // nargs
do_call:
func = Stack[SP-n-1];
s = SP;
if (tag(func) == TAG_FUNCTION) {
if (func > (N_BUILTINS<<3)) {
v = apply_cl(n);
}
else {
op = uintval(func);
if (op > OP_ASET)
type_error("apply", "function", func);
s = builtin_arg_counts[op];
if (s >= 0)
argcount(builtin_names[op], n, s);
else if (s != ANYARGS && (signed)n < -s)
argcount(builtin_names[op], n, -s);
// remove function arg
for(s=SP-n-1; s < (int)SP-1; s++)
Stack[s] = Stack[s+1];
SP--;
switch (op) {
case OP_LIST: goto apply_list;
case OP_VECTOR: goto apply_vector;
case OP_APPLY: goto apply_apply;
case OP_ADD: goto apply_add;
case OP_SUB: goto apply_sub;
case OP_MUL: goto apply_mul;
case OP_DIV: goto apply_div;
default:
goto dispatch;
}
}
}
else if (iscbuiltin(func)) {
v = (((builtin_t*)ptr(func))[3])(&Stack[SP-n], n);
}
else {
type_error("apply", "function", func);
}
SP = s-n;
Stack[SP-1] = v;
goto next_op;
case OP_JMP: ip = (uint32_t)*(uint16_t*)&code[ip]; goto next_op;
case OP_BRF:
v = POP();
if (v == FL_F) ip = (uint32_t)*(uint16_t*)&code[ip];
else ip += 2;
goto next_op;
case OP_BRT:
v = POP();
if (v != FL_F) ip = (uint32_t)*(uint16_t*)&code[ip];
else ip += 2;
goto next_op;
case OP_JMPL: ip = *(uint32_t*)&code[ip]; goto next_op;
case OP_BRFL:
v = POP();
if (v == FL_F) ip = *(uint32_t*)&code[ip];
else ip += 4;
goto next_op;
case OP_BRTL:
v = POP();
if (v != FL_F) ip = *(uint32_t*)&code[ip];
else ip += 4;
goto next_op;
case OP_RET: v = POP(); return v;
case OP_EQ:
Stack[SP-2] = ((Stack[SP-2] == Stack[SP-1]) ? FL_T : FL_F);
POPN(1); goto next_op;
case OP_EQV:
if (Stack[SP-2] == Stack[SP-1]) {
v = FL_T;
}
else if (!leafp(Stack[SP-2]) || !leafp(Stack[SP-1])) {
v = FL_F;
}
else {
v = equal(Stack[SP-2], Stack[SP-1]);
}
Stack[SP-2] = v; POPN(1);
goto next_op;
case OP_EQUAL:
if (Stack[SP-2] == Stack[SP-1]) {
v = FL_T;
}
else {
v = equal(Stack[SP-2], Stack[SP-1]);
}
Stack[SP-2] = v; POPN(1);
goto next_op;
case OP_PAIRP:
Stack[SP-1] = (iscons(Stack[SP-1]) ? FL_T : FL_F); goto next_op;
case OP_ATOMP:
Stack[SP-1] = (iscons(Stack[SP-1]) ? FL_F : FL_T); goto next_op;
case OP_NOT:
Stack[SP-1] = ((Stack[SP-1]==FL_F) ? FL_T : FL_F); goto next_op;
case OP_NULLP:
Stack[SP-1] = ((Stack[SP-1]==NIL) ? FL_T : FL_F); goto next_op;
case OP_BOOLEANP:
v = Stack[SP-1];
Stack[SP-1] = ((v == FL_T || v == FL_F) ? FL_T:FL_F); goto next_op;
case OP_SYMBOLP:
Stack[SP-1] = (issymbol(Stack[SP-1]) ? FL_T : FL_F); goto next_op;
case OP_NUMBERP:
v = Stack[SP-1];
Stack[SP-1] = (isfixnum(v) || iscprim(v) ? FL_T:FL_F); goto next_op;
case OP_FIXNUMP:
Stack[SP-1] = (isfixnum(Stack[SP-1]) ? FL_T : FL_F); goto next_op;
case OP_BOUNDP:
sym = tosymbol(Stack[SP-1], "bound?");
Stack[SP-1] = ((sym->binding == UNBOUND) ? FL_F : FL_T);
goto next_op;
case OP_BUILTINP:
v = Stack[SP-1];
Stack[SP-1] = (isbuiltin(v) || iscbuiltin(v)) ? FL_T : FL_F;
goto next_op;
case OP_FUNCTIONP:
v = Stack[SP-1];
Stack[SP-1] = ((tag(v)==TAG_FUNCTION &&v!=FL_F&&v!=FL_T&&v!=NIL) ||
iscbuiltin(v)) ? FL_T : FL_F;
goto next_op;
case OP_VECTORP:
Stack[SP-1] = (isvector(Stack[SP-1]) ? FL_T : FL_F); goto next_op;
case OP_CONS:
if (curheap > lim)
gc(0);
c = (cons_t*)curheap;
curheap += sizeof(cons_t);
c->car = Stack[SP-2];
c->cdr = Stack[SP-1];
Stack[SP-2] = tagptr(c, TAG_CONS);
POPN(1); goto next_op;
case OP_CAR:
v = Stack[SP-1];
if (!iscons(v)) type_error("car", "cons", v);
Stack[SP-1] = car_(v);
goto next_op;
case OP_CDR:
v = Stack[SP-1];
if (!iscons(v)) type_error("cdr", "cons", v);
Stack[SP-1] = cdr_(v);
goto next_op;
case OP_SETCAR:
car(Stack[SP-2]) = Stack[SP-1];
POPN(1); goto next_op;
case OP_SETCDR:
cdr(Stack[SP-2]) = Stack[SP-1];
POPN(1); goto next_op;
case OP_LIST:
n = code[ip++];
apply_list:
if (n > 0) {
v = list(&Stack[SP-n], n);
POPN(n);
PUSH(v);
}
else {
PUSH(NIL);
}
goto next_op;
case OP_TAPPLY:
case OP_APPLY:
n = code[ip++];
apply_apply:
v = POP(); // arglist
if (n > MAX_ARGS) {
v = apply_liststar(v);
}
n = SP-(n-2); // n-2 == # leading arguments not in the list
while (iscons(v)) {
if (SP-n == MAX_ARGS) {
PUSH(v);
break;
}
PUSH(car_(v));
v = cdr_(v);
}
n = SP-n;
if (op==OP_TAPPLY) goto do_tcall;
else goto do_call;
case OP_ADD:
n = code[ip++];
apply_add:
s = 0;
i = SP-n;
if (n > MAX_ARGS) goto add_ovf;
for (; i < SP; i++) {
if (isfixnum(Stack[i])) {
s += numval(Stack[i]);
if (!fits_fixnum(s)) {
i++;
goto add_ovf;
}
}
else {
add_ovf:
v = fl_add_any(&Stack[i], SP-i, s);
break;
}
}
if (i==SP)
v = fixnum(s);
POPN(n);
PUSH(v);
goto next_op;
case OP_ADD2:
if (bothfixnums(Stack[SP-1], Stack[SP-2])) {
s = numval(Stack[SP-1]) + numval(Stack[SP-2]);
if (fits_fixnum(s))
v = fixnum(s);
else
v = mk_long(s);
}
else {
v = fl_add_any(&Stack[SP-2], 2, 0);
}
POPN(1);
Stack[SP-1] = v;
goto next_op;
case OP_SUB:
n = code[ip++];
apply_sub:
if (n == 2) goto do_sub2;
if (n == 1) goto do_neg;
i = SP-n;
// we need to pass the full arglist on to fl_add_any
// so it can handle rest args properly
PUSH(Stack[i]);
Stack[i] = fixnum(0);
Stack[i+1] = fl_neg(fl_add_any(&Stack[i], n, 0));
Stack[i] = POP();
v = fl_add_any(&Stack[i], 2, 0);
POPN(n);
PUSH(v);
goto next_op;
case OP_NEG:
do_neg:
if (isfixnum(Stack[SP-1]))
Stack[SP-1] = fixnum(-numval(Stack[SP-1]));
else
Stack[SP-1] = fl_neg(Stack[SP-1]);
goto next_op;
case OP_SUB2:
do_sub2:
if (bothfixnums(Stack[SP-2], Stack[SP-1])) {
s = numval(Stack[SP-2]) - numval(Stack[SP-1]);
if (fits_fixnum(s))
v = fixnum(s);
else
v = mk_long(s);
}
else {
Stack[SP-1] = fl_neg(Stack[SP-1]);
v = fl_add_any(&Stack[SP-2], 2, 0);
}
POPN(1);
Stack[SP-1] = v;
goto next_op;
case OP_MUL:
n = code[ip++];
apply_mul:
accum = 1;
i = SP-n;
if (n > MAX_ARGS) goto mul_ovf;
for (; i < SP; i++) {
if (isfixnum(Stack[i])) {
accum *= numval(Stack[i]);
}
else {
mul_ovf:
v = fl_mul_any(&Stack[i], SP-i, accum);
break;
}
}
if (i == SP) {
if (fits_fixnum(accum))
v = fixnum(accum);
else
v = return_from_int64(accum);
}
POPN(n);
PUSH(v);
goto next_op;
case OP_DIV:
n = code[ip++];
apply_div:
i = SP-n;
if (n == 1) {
Stack[SP-1] = fl_div2(fixnum(1), Stack[i]);
}
else {
if (n > 2) {
PUSH(Stack[i]);
Stack[i] = fixnum(1);
Stack[i+1] = fl_mul_any(&Stack[i], n, 1);
Stack[i] = POP();
}
v = fl_div2(Stack[i], Stack[i+1]);
POPN(n);
PUSH(v);
}
goto next_op;
case OP_IDIV:
v = Stack[SP-2]; e = Stack[SP-1];
if (bothfixnums(v, e)) {
if (e==0) DivideByZeroError();
v = fixnum(numval(v) / numval(e));
}
else
v = fl_idiv2(v, e);
POPN(1);
Stack[SP-1] = v;
goto next_op;
case OP_NUMEQ:
v = Stack[SP-2]; e = Stack[SP-1];
if (bothfixnums(v, e))
v = (v == e) ? FL_T : FL_F;
else
v = (!numeric_compare(v,e,1,0,"=")) ? FL_T : FL_F;
POPN(1);
Stack[SP-1] = v;
goto next_op;
case OP_LT:
if (bothfixnums(Stack[SP-2], Stack[SP-1])) {
v = (numval(Stack[SP-2]) < numval(Stack[SP-1])) ? FL_T : FL_F;
}
else {
v = (numval(compare(Stack[SP-2], Stack[SP-1])) < 0) ?
FL_T : FL_F;
}
POPN(1);
Stack[SP-1] = v;
goto next_op;
case OP_COMPARE:
Stack[SP-2] = compare(Stack[SP-2], Stack[SP-1]);
POPN(1);
goto next_op;
case OP_VECTOR:
n = code[ip++];
apply_vector:
if (n > MAX_ARGS) {
i = llength(Stack[SP-1])-1;
}
else i = 0;
v = alloc_vector(n+i, 0);
if (n) {
memcpy(&vector_elt(v,0), &Stack[SP-n], n*sizeof(value_t));
e = POP();
POPN(n-1);
}
if (n > MAX_ARGS) {
i = n-1;
while (iscons(e)) {
vector_elt(v,i) = car_(e);
i++;
e = cdr_(e);
}
}
PUSH(v);
goto next_op;
case OP_AREF:
v = Stack[SP-2];
if (isvector(v)) {
i = tofixnum(Stack[SP-1], "aref");
if ((unsigned)i >= vector_size(v))
bounds_error("aref", v, Stack[SP-1]);
v = vector_elt(v, i);
}
else if (isarray(v)) {
v = cvalue_array_aref(&Stack[SP-2]);
}
else {
type_error("aref", "sequence", v);
}
POPN(1);
Stack[SP-1] = v;
goto next_op;
case OP_ASET:
e = Stack[SP-3];
if (isvector(e)) {
i = tofixnum(Stack[SP-2], "aset!");
if ((unsigned)i >= vector_size(e))
bounds_error("aset!", v, Stack[SP-1]);
vector_elt(e, i) = (v=Stack[SP-1]);
}
else if (isarray(e)) {
v = cvalue_array_aset(&Stack[SP-3]);
}
else {
type_error("aset!", "sequence", e);
}
POPN(2);
Stack[SP-1] = v;
goto next_op;
case OP_FOR:
s = tofixnum(Stack[SP-3], "for");
hi = tofixnum(Stack[SP-2], "for");
//f = Stack[SP-1];
v = FL_F;
SP += 2;
i = SP;
for(; s <= hi; s++) {
Stack[SP-2] = Stack[SP-3];
Stack[SP-1] = fixnum(s);
v = apply_cl(1);
SP = i;
}
POPN(4);
Stack[SP-1] = v;
goto next_op;
case OP_LOADT: PUSH(FL_T); goto next_op;
case OP_LOADF: PUSH(FL_F); goto next_op;
case OP_LOADNIL: PUSH(NIL); goto next_op;
case OP_LOAD0: PUSH(fixnum(0)); goto next_op;
case OP_LOAD1: PUSH(fixnum(1)); goto next_op;
case OP_LOADI8: s = (int8_t)code[ip++]; PUSH(fixnum(s)); goto next_op;
case OP_LOADV:
v = fn_vals(Stack[bp-1]);
assert(code[ip] < vector_size(v));
v = vector_elt(v, code[ip]); ip++;
PUSH(v);
goto next_op;
case OP_LOADVL:
v = fn_vals(Stack[bp-1]);
v = vector_elt(v, *(uint32_t*)&code[ip]); ip+=4;
PUSH(v);
goto next_op;
case OP_LOADGL:
v = fn_vals(Stack[bp-1]);
v = vector_elt(v, *(uint32_t*)&code[ip]); ip+=4;
goto do_loadg;
case OP_LOADG:
v = fn_vals(Stack[bp-1]);
assert(code[ip] < vector_size(v));
v = vector_elt(v, code[ip]); ip++;
do_loadg:
assert(issymbol(v));
sym = (symbol_t*)ptr(v);
if (sym->binding == UNBOUND)
raise(list2(UnboundError, v));
PUSH(sym->binding);
goto next_op;
case OP_SETGL:
v = fn_vals(Stack[bp-1]);
v = vector_elt(v, *(uint32_t*)&code[ip]); ip+=4;
goto do_setg;
case OP_SETG:
v = fn_vals(Stack[bp-1]);
assert(code[ip] < vector_size(v));
v = vector_elt(v, code[ip]); ip++;
do_setg:
assert(issymbol(v));
sym = (symbol_t*)ptr(v);
v = Stack[SP-1];
if (sym->syntax != TAG_CONST)
sym->binding = v;
goto next_op;
case OP_LOADA:
assert(nargs > 0);
i = code[ip++];
if (captured) {
x = Stack[bp];
assert(isvector(x));
assert(i < vector_size(x));
v = vector_elt(x, i);
}
else {
assert(bp+i < SP);
v = Stack[bp+i];
}
PUSH(v);
goto next_op;
case OP_SETA:
assert(nargs > 0);
v = Stack[SP-1];
i = code[ip++];
if (captured) {
x = Stack[bp];
assert(isvector(x));
assert(i < vector_size(x));
vector_elt(x, i) = v;
}
else {
assert(bp+i < SP);
Stack[bp+i] = v;
}
goto next_op;
case OP_LOADC:
case OP_SETC:
s = code[ip++];
i = code[ip++];
v = Stack[bp+nargs];
while (s--)
v = vector_elt(v, vector_size(v)-1);
assert(isvector(v));
assert(i < vector_size(v));
if (op == OP_SETC)
vector_elt(v, i) = Stack[SP-1];
else
PUSH(vector_elt(v, i));
goto next_op;
case OP_CLOSURE:
case OP_COPYENV:
// build a closure (lambda args body . env)
if (nargs > 0 && !captured) {
// save temporary environment to the heap
lenv = &Stack[bp];
envsz = nargs+1;
pv = alloc_words(envsz + 1);
PUSH(tagptr(pv, TAG_VECTOR));
pv[0] = fixnum(envsz);
pv++;
while (envsz--)
*pv++ = *lenv++;
// environment representation changed; install
// the new representation so everybody can see it
captured = 1;
Stack[bp] = Stack[SP-1];
}
else {
PUSH(Stack[bp]); // env has already been captured; share
}
if (op == OP_CLOSURE) {
pv = alloc_words(4);
x = Stack[SP-2]; // closure to copy
assert(isfunction(x));
pv[0] = ((value_t*)ptr(x))[0];
pv[1] = ((value_t*)ptr(x))[1];
pv[2] = Stack[SP-1]; // env
POPN(1);
Stack[SP-1] = tagptr(pv, TAG_FUNCTION);
}
goto next_op;
case OP_TRYCATCH:
v = do_trycatch();
POPN(1);
Stack[SP-1] = v;
goto next_op;
}
}
assert(0);
return UNBOUND;
}
// initialization -------------------------------------------------------------
extern void builtins_init();
extern void comparehash_init();
static char *EXEDIR = NULL;
void assign_global_builtins(builtinspec_t *b)
{
while (b->name != NULL) {
set(symbol(b->name), cbuiltin(b->name, b->fptr));
b++;
}
}
static value_t fl_function(value_t *args, uint32_t nargs)
{
if (nargs != 3)
argcount("function", nargs, 2);
if (!isstring(args[0]))
type_error("function", "string", args[0]);
if (!isvector(args[1]))
type_error("function", "vector", args[1]);
cvalue_t *arr = (cvalue_t*)ptr(args[0]);
cv_pin(arr);
char *data = cv_data(arr);
if (data[0] >= N_OPCODES) {
// read syntax, shifted 48 for compact text representation
size_t i, sz = cv_len(arr);
for(i=0; i < sz; i++)
data[i] -= 48;
}
function_t *fn = (function_t*)alloc_words(4);
value_t fv = tagptr(fn, TAG_FUNCTION);
fn->bcode = args[0];
fn->vals = args[1];
if (nargs == 3)
fn->env = args[2];
else
fn->env = NIL;
return fv;
}
static value_t fl_function_code(value_t *args, uint32_t nargs)
{
argcount("function:code", nargs, 1);
value_t v = args[0];
if (!isclosure(v)) type_error("function:code", "function", v);
return fn_bcode(v);
}
static value_t fl_function_vals(value_t *args, uint32_t nargs)
{
argcount("function:vals", nargs, 1);
value_t v = args[0];
if (!isclosure(v)) type_error("function:vals", "function", v);
return fn_vals(v);
}
static value_t fl_function_env(value_t *args, uint32_t nargs)
{
argcount("function:env", nargs, 1);
value_t v = args[0];
if (!isclosure(v)) type_error("function:env", "function", v);
return fn_env(v);
}
static builtinspec_t core_builtin_info[] = {
{ "function", fl_function },
{ "function:code", fl_function_code },
{ "function:vals", fl_function_vals },
{ "function:env", fl_function_env },
{ "gensym", fl_gensym },
{ "hash", fl_hash },
{ NULL, NULL }
};
static void lisp_init(void)
{
int i;
llt_init();
fromspace = malloc(heapsize);
tospace = malloc(heapsize);
curheap = fromspace;
lim = curheap+heapsize-sizeof(cons_t);
consflags = bitvector_new(heapsize/sizeof(cons_t), 1);
htable_new(&printconses, 32);
comparehash_init();
NIL = builtin(OP_THE_EMPTY_LIST);
FL_T = builtin(OP_BOOL_CONST_T);
FL_F = builtin(OP_BOOL_CONST_F);
LAMBDA = symbol("lambda");
FUNCTION = symbol("function");
QUOTE = symbol("quote");
TRYCATCH = symbol("trycatch");
BACKQUOTE = symbol("backquote");
COMMA = symbol("*comma*");
COMMAAT = symbol("*comma-at*");
COMMADOT = symbol("*comma-dot*");
IOError = symbol("io-error");
ParseError = symbol("parse-error");
TypeError = symbol("type-error");
ArgError = symbol("arg-error");
UnboundError = symbol("unbound-error");
KeyError = symbol("key-error");
MemoryError = symbol("memory-error");
BoundsError = symbol("bounds-error");
DivideError = symbol("divide-error");
EnumerationError = symbol("enumeration-error");
Error = symbol("error");
conssym = symbol("cons");
symbolsym = symbol("symbol");
fixnumsym = symbol("fixnum");
vectorsym = symbol("vector");
builtinsym = symbol("builtin");
booleansym = symbol("boolean");
nullsym = symbol("null");
definesym = symbol("define");
defmacrosym = symbol("define-macro");
forsym = symbol("for");
labelsym = symbol("label");
setqsym = symbol("set!");
evalsym = symbol("eval");
vu8sym = symbol("vu8");
tsym = symbol("t"); Tsym = symbol("T");
fsym = symbol("f"); Fsym = symbol("F");
set(printprettysym=symbol("*print-pretty*"), FL_T);
set(printreadablysym=symbol("*print-readably*"), FL_T);
set(printwidthsym=symbol("*print-width*"), fixnum(SCR_WIDTH));
lasterror = NIL;
i = 0;
for (i=OP_EQ; i <= OP_ASET; i++) {
setc(symbol(builtin_names[i]), builtin(i));
}
setc(symbol("eq"), builtin(OP_EQ));
setc(symbol("equal"), builtin(OP_EQUAL));
setc(symbol("procedure?"), builtin(OP_FUNCTIONP));
#ifdef LINUX
setc(symbol("*os-name*"), symbol("linux"));
#elif defined(WIN32) || defined(WIN64)
setc(symbol("*os-name*"), symbol("win32"));
#elif defined(MACOSX)
setc(symbol("*os-name*"), symbol("macos"));
#else
setc(symbol("*os-name*"), symbol("unknown"));
#endif
cvalues_init();
char buf[1024];
char *exename = get_exename(buf, sizeof(buf));
if (exename != NULL) {
path_to_dirname(exename);
EXEDIR = strdup(exename);
setc(symbol("*install-dir*"), cvalue_static_cstring(EXEDIR));
}
memory_exception_value = list2(MemoryError,
cvalue_static_cstring("out of memory"));
the_empty_vector = tagptr(alloc_words(1), TAG_VECTOR);
vector_setsize(the_empty_vector, 0);
assign_global_builtins(core_builtin_info);
builtins_init();
}
// repl -----------------------------------------------------------------------
value_t toplevel_eval(value_t expr)
{
value_t v;
uint32_t saveSP = SP;
PUSH(symbol_value(evalsym));
PUSH(expr);
v = apply_cl(1);
SP = saveSP;
return v;
}
static value_t argv_list(int argc, char *argv[])
{
int i;
PUSH(NIL);
for(i=argc-1; i >= 0; i--) {
PUSH(cvalue_static_cstring(argv[i]));
Stack[SP-2] = fl_cons(Stack[SP-1], Stack[SP-2]);
POPN(1);
}
return POP();
}
int locale_is_utf8;
extern value_t fl_file(value_t *args, uint32_t nargs);
int main(int argc, char *argv[])
{
value_t e, v;
int saveSP;
symbol_t *sym;
char fname_buf[1024];
locale_is_utf8 = u8_is_locale_utf8(setlocale(LC_ALL, ""));
lisp_init();
fname_buf[0] = '\0';
if (EXEDIR != NULL) {
strcat(fname_buf, EXEDIR);
strcat(fname_buf, PATHSEPSTRING);
}
strcat(fname_buf, "flisp.boot");
FL_TRY {
// install toplevel exception handler
PUSH(cvalue_static_cstring(fname_buf));
PUSH(symbol(":read"));
value_t f = fl_file(&Stack[SP-2], 2);
POPN(2);
PUSH(f); saveSP = SP;
while (1) {
e = read_sexpr(Stack[SP-1]);
if (ios_eof(value2c(ios_t*,Stack[SP-1]))) break;
if (isfunction(e)) {
// stage 0 format: series of thunks
PUSH(e);
(void)_applyn(0);
SP = saveSP;
}
else {
// stage 1 format: symbol/value pairs
sym = tosymbol(e, "bootstrap");
v = read_sexpr(Stack[SP-1]);
sym->binding = v;
}
}
ios_close(value2c(ios_t*,Stack[SP-1]));
POPN(1);
PUSH(symbol_value(symbol("__start")));
PUSH(argv_list(argc, argv));
(void)_applyn(1);
}
FL_CATCH {
ios_puts("fatal error during bootstrap:\n", ios_stderr);
print(ios_stderr, lasterror);
ios_putc('\n', ios_stderr);
return 1;
}
return 0;
}