int bytecode_operation_length(uint16_t* codeptr) {
int length = opcode_describe(*codeptr)->length;
if (*codeptr == CALL_JQ || *codeptr == TAIL_CALL_JQ) {
length += codeptr[1] * 2;
}
return length;
}
block gen_op_target(opcode op, block target) {
assert(opcode_describe(op)->flags & OP_HAS_BRANCH);
assert(target.last);
inst* i = inst_new(op);
i->imm.target = target.last;
return inst_block(i);
}
static void inst_free(struct inst* i) {
jv_mem_free(i->symbol);
block_free(i->subfn);
block_free(i->arglist);
if (opcode_describe(i->op)->flags & OP_HAS_CONSTANT) {
jv_free(i->imm.constant);
}
jv_mem_free(i);
}
int block_has_only_binders(block binders, int bindflags) {
bindflags |= OP_HAS_BINDING;
for (inst* curr = binders.first; curr; curr = curr->next) {
if ((opcode_describe(curr->op)->flags & bindflags) != bindflags) {
return 0;
}
}
return 1;
}
void dump_operation(struct bytecode* bc, uint16_t* codeptr) {
int pc = codeptr - bc->code;
printf("%04d ", pc);
const struct opcode_description* op = opcode_describe(bc->code[pc++]);
printf("%s", op->name);
if (op->length > 1) {
uint16_t imm = bc->code[pc++];
if (op->op == CALL_JQ || op->op == TAIL_CALL_JQ) {
for (int i=0; i<imm+1; i++) {
uint16_t level = bc->code[pc++];
uint16_t idx = bc->code[pc++];
jv name;
if (idx & ARG_NEWCLOSURE) {
idx &= ~ARG_NEWCLOSURE;
name = jv_object_get(jv_copy(getlevel(bc,level)->subfunctions[idx]->debuginfo),
jv_string("name"));
} else {
name = jv_array_get(jv_object_get(jv_copy(getlevel(bc,level)->debuginfo),
jv_string("params")), idx);
}
printf(" %s:%d",
jv_string_value(name),
idx);
jv_free(name);
if (level) {
printf("^%d", level);
}
}
} else if (op->op == CALL_BUILTIN) {
int func = bc->code[pc++];
jv name = jv_array_get(jv_copy(bc->globals->cfunc_names), func);
printf(" %s", jv_string_value(name));
jv_free(name);
} else if (op->flags & OP_HAS_BRANCH) {
printf(" %04d", pc + imm);
} else if (op->flags & OP_HAS_CONSTANT) {
printf(" ");
jv_dump(jv_array_get(jv_copy(bc->constants), imm), 0);
} else if (op->flags & OP_HAS_VARIABLE) {
uint16_t v = bc->code[pc++];
jv name = jv_array_get(jv_object_get(jv_copy(getlevel(bc,imm)->debuginfo), jv_string("locals")), v);
printf(" $%s:%d",
jv_string_value(name),
v);
jv_free(name);
if (imm) {
printf("^%d", imm);
}
} else {
printf(" %d", imm);
}
}
}
static int block_bind_subblock(block binder, block body, int bindflags) {
assert(block_is_single(binder));
assert((opcode_describe(binder.first->op)->flags & bindflags) == bindflags);
assert(binder.first->symbol);
assert(binder.first->bound_by == 0 || binder.first->bound_by == binder.first);
binder.first->bound_by = binder.first;
int nrefs = 0;
for (inst* i = body.first; i; i = i->next) {
int flags = opcode_describe(i->op)->flags;
if ((flags & bindflags) == bindflags &&
i->bound_by == 0 &&
!strcmp(i->symbol, binder.first->symbol)) {
// bind this instruction
i->bound_by = binder.first;
nrefs++;
}
// binding recurses into closures
nrefs += block_bind_subblock(binder, i->subfn, bindflags);
// binding recurses into argument list
nrefs += block_bind_subblock(binder, i->arglist, bindflags);
}
return nrefs;
}
static int compile(struct locfile* locations, struct bytecode* bc, block b) {
int errors = 0;
int pos = 0;
int var_frame_idx = 0;
bc->nsubfunctions = 0;
errors += expand_call_arglist(locations, &b);
b = BLOCK(b, gen_op_simple(RET));
jv localnames = jv_array();
for (inst* curr = b.first; curr; curr = curr->next) {
if (!curr->next) assert(curr == b.last);
int length = opcode_describe(curr->op)->length;
if (curr->op == CALL_JQ) {
for (inst* arg = curr->arglist.first; arg; arg = arg->next) {
length += 2;
}
}
pos += length;
curr->bytecode_pos = pos;
curr->compiled = bc;
assert(curr->op != CLOSURE_REF && curr->op != CLOSURE_PARAM);
if ((opcode_describe(curr->op)->flags & OP_HAS_VARIABLE) &&
curr->bound_by == curr) {
curr->imm.intval = var_frame_idx++;
localnames = jv_array_append(localnames, jv_string(curr->symbol));
}
if (curr->op == CLOSURE_CREATE) {
assert(curr->bound_by == curr);
curr->imm.intval = bc->nsubfunctions++;
}
if (curr->op == CLOSURE_CREATE_C) {
assert(curr->bound_by == curr);
int idx = bc->globals->ncfunctions++;
bc->globals->cfunc_names = jv_array_append(bc->globals->cfunc_names,
jv_string(curr->symbol));
bc->globals->cfunctions[idx] = *curr->imm.cfunc;
curr->imm.intval = idx;
}
}
bc->debuginfo = jv_object_set(bc->debuginfo, jv_string("locals"), localnames);
if (bc->nsubfunctions) {
bc->subfunctions = jv_mem_alloc(sizeof(struct bytecode*) * bc->nsubfunctions);
for (inst* curr = b.first; curr; curr = curr->next) {
if (curr->op == CLOSURE_CREATE) {
struct bytecode* subfn = jv_mem_alloc(sizeof(struct bytecode));
bc->subfunctions[curr->imm.intval] = subfn;
subfn->globals = bc->globals;
subfn->parent = bc;
subfn->nclosures = 0;
subfn->debuginfo = jv_object_set(jv_object(), jv_string("name"), jv_string(curr->symbol));
jv params = jv_array();
for (inst* param = curr->arglist.first; param; param = param->next) {
assert(param->op == CLOSURE_PARAM);
assert(param->bound_by == param);
param->imm.intval = subfn->nclosures++;
param->compiled = subfn;
params = jv_array_append(params, jv_string(param->symbol));
}
subfn->debuginfo = jv_object_set(subfn->debuginfo, jv_string("params"), params);
errors += compile(locations, subfn, curr->subfn);
curr->subfn = gen_noop();
}
}
} else {
bc->subfunctions = 0;
}
bc->codelen = pos;
uint16_t* code = jv_mem_alloc(sizeof(uint16_t) * bc->codelen);
bc->code = code;
pos = 0;
jv constant_pool = jv_array();
int maxvar = -1;
if (!errors) for (inst* curr = b.first; curr; curr = curr->next) {
const struct opcode_description* op = opcode_describe(curr->op);
if (op->length == 0)
continue;
code[pos++] = curr->op;
assert(curr->op != CLOSURE_REF && curr->op != CLOSURE_PARAM);
if (curr->op == CALL_BUILTIN) {
assert(curr->bound_by->op == CLOSURE_CREATE_C);
assert(!curr->arglist.first);
code[pos++] = (uint16_t)curr->imm.intval;
code[pos++] = curr->bound_by->imm.intval;
} else if (curr->op == CALL_JQ) {
assert(curr->bound_by->op == CLOSURE_CREATE ||
curr->bound_by->op == CLOSURE_PARAM);
code[pos++] = (uint16_t)curr->imm.intval;
code[pos++] = nesting_level(bc, curr->bound_by);
code[pos++] = curr->bound_by->imm.intval |
(curr->bound_by->op == CLOSURE_CREATE ? ARG_NEWCLOSURE : 0);
for (inst* arg = curr->arglist.first; arg; arg = arg->next) {
assert(arg->op == CLOSURE_REF && arg->bound_by->op == CLOSURE_CREATE);
code[pos++] = nesting_level(bc, arg->bound_by);
code[pos++] = arg->bound_by->imm.intval | ARG_NEWCLOSURE;
}
} else if (op->flags & OP_HAS_CONSTANT) {
code[pos++] = jv_array_length(jv_copy(constant_pool));
constant_pool = jv_array_append(constant_pool, jv_copy(curr->imm.constant));
} else if (op->flags & OP_HAS_VARIABLE) {
code[pos++] = nesting_level(bc, curr->bound_by);
uint16_t var = (uint16_t)curr->bound_by->imm.intval;
code[pos++] = var;
if (var > maxvar) maxvar = var;
} else if (op->flags & OP_HAS_BRANCH) {
assert(curr->imm.target->bytecode_pos != -1);
assert(curr->imm.target->bytecode_pos > pos); // only forward branches
code[pos] = curr->imm.target->bytecode_pos - (pos + 1);
pos++;
} else if (op->length > 1) {
assert(0 && "codegen not implemented for this operation");
}
}
bc->constants = constant_pool;
bc->nlocals = maxvar + 2; // FIXME: frames of size zero?
block_free(b);
return errors;
}
// Expands call instructions into a calling sequence
static int expand_call_arglist(struct locfile* locations, block* b) {
int errors = 0;
block ret = gen_noop();
for (inst* curr; (curr = block_take(b));) {
if (opcode_describe(curr->op)->flags & OP_HAS_BINDING) {
if (!curr->bound_by) {
locfile_locate(locations, curr->source, "error: %s is not defined", curr->symbol);
errors++;
// don't process this instruction if it's not well-defined
ret = BLOCK(ret, inst_block(curr));
continue;
}
}
block prelude = gen_noop();
if (curr->op == CALL_JQ) {
int actual_args = 0, desired_args = 0;
// We expand the argument list as a series of instructions
switch (curr->bound_by->op) {
default: assert(0 && "Unknown function type"); break;
case CLOSURE_CREATE:
case CLOSURE_PARAM: {
block callargs = gen_noop();
for (inst* i; (i = block_take(&curr->arglist));) {
assert(opcode_describe(i->op)->flags & OP_IS_CALL_PSEUDO);
block b = inst_block(i);
switch (i->op) {
default: assert(0 && "Unknown type of parameter"); break;
case CLOSURE_REF:
block_append(&callargs, b);
break;
case CLOSURE_CREATE:
block_append(&prelude, b);
block_append(&callargs, gen_op_bound(CLOSURE_REF, b));
break;
}
actual_args++;
}
curr->imm.intval = actual_args;
curr->arglist = callargs;
if (curr->bound_by->op == CLOSURE_CREATE) {
for (inst* i = curr->bound_by->arglist.first; i; i = i->next) {
assert(i->op == CLOSURE_PARAM);
desired_args++;
}
}
break;
}
case CLOSURE_CREATE_C: {
for (inst* i; (i = block_take(&curr->arglist)); ) {
assert(i->op == CLOSURE_CREATE); // FIXME
block body = i->subfn;
i->subfn = gen_noop();
inst_free(i);
// arguments should be pushed in reverse order, prepend them to prelude
errors += expand_call_arglist(locations, &body);
prelude = BLOCK(gen_subexp(body), prelude);
actual_args++;
}
assert(curr->op == CALL_JQ);
curr->op = CALL_BUILTIN;
curr->imm.intval = actual_args + 1 /* include the implicit input in arg count */;
assert(curr->bound_by->op == CLOSURE_CREATE_C);
desired_args = curr->bound_by->imm.cfunc->nargs - 1;
assert(!curr->arglist.first);
break;
}
}
if (actual_args != desired_args) {
locfile_locate(locations, curr->source,
"error: %s arguments to %s (expected %d but got %d)",
actual_args > desired_args ? "too many" : "too few",
curr->symbol, desired_args, actual_args);
errors++;
}
}
ret = BLOCK(ret, prelude, inst_block(curr));
}
*b = ret;
return errors;
}
block gen_op_var_fresh(opcode op, const char* name) {
assert(opcode_describe(op)->flags & OP_HAS_VARIABLE);
return block_bind(gen_op_unbound(op, name),
gen_noop(), OP_HAS_VARIABLE);
}
block gen_op_unbound(opcode op, const char* name) {
assert(opcode_describe(op)->flags & OP_HAS_BINDING);
inst* i = inst_new(op);
i->symbol = strdup(name);
return inst_block(i);
}
void inst_set_target(block b, block target) {
assert(block_is_single(b));
assert(opcode_describe(b.first->op)->flags & OP_HAS_BRANCH);
assert(target.last);
b.first->imm.target = target.last;
}
block gen_op_targetlater(opcode op) {
assert(opcode_describe(op)->flags & OP_HAS_BRANCH);
inst* i = inst_new(op);
i->imm.target = 0;
return inst_block(i);
}
block gen_const(jv constant) {
assert(opcode_describe(LOADK)->flags & OP_HAS_CONSTANT);
inst* i = inst_new(LOADK);
i->imm.constant = constant;
return inst_block(i);
}
block gen_op_simple(opcode op) {
assert(opcode_describe(op)->length == 1);
return inst_block(inst_new(op));
}
jv jq_next(jq_state *jq) {
jv cfunc_input[MAX_CFUNCTION_ARGS];
jv_nomem_handler(jq->nomem_handler, jq->nomem_handler_data);
uint16_t* pc = stack_restore(jq);
assert(pc);
int backtracking = !jq->initial_execution;
jq->initial_execution = 0;
while (1) {
uint16_t opcode = *pc;
if (jq->debug_trace_enabled) {
dump_operation(frame_current(jq)->bc, pc);
printf("\t");
const struct opcode_description* opdesc = opcode_describe(opcode);
stack_ptr param = 0;
if (!backtracking) {
int stack_in = opdesc->stack_in;
if (stack_in == -1) stack_in = pc[1];
int i;
for (i=0; i<stack_in; i++) {
if (i == 0) {
param = jq->stk_top;
} else {
printf(" | ");
param = *stack_block_next(&jq->stk, param);
}
if (!param) break;
jv_dump(jv_copy(*(jv*)stack_block(&jq->stk, param)), 0);
//printf("<%d>", jv_get_refcnt(param->val));
//printf(" -- ");
//jv_dump(jv_copy(jq->path), 0);
}
} else {
printf("\t<backtracking>");
}
printf("\n");
}
if (backtracking) {
opcode = ON_BACKTRACK(opcode);
backtracking = 0;
}
pc++;
switch (opcode) {
default: assert(0 && "invalid instruction");
case LOADK: {
jv v = jv_array_get(jv_copy(frame_current(jq)->bc->constants), *pc++);
assert(jv_is_valid(v));
jv_free(stack_pop(jq));
stack_push(jq, v);
break;
}
case DUP: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
break;
}
case DUP2: {
jv keep = stack_pop(jq);
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, keep);
stack_push(jq, v);
break;
}
case SUBEXP_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
jq->subexp_nest++;
break;
}
case SUBEXP_END: {
assert(jq->subexp_nest > 0);
jq->subexp_nest--;
jv a = stack_pop(jq);
jv b = stack_pop(jq);
stack_push(jq, a);
stack_push(jq, b);
break;
}
case POP: {
jv_free(stack_pop(jq));
break;
}
case APPEND: {
jv v = stack_pop(jq);
uint16_t level = *pc++;
uint16_t vidx = *pc++;
jv* var = frame_local_var(jq, vidx, level);
assert(jv_get_kind(*var) == JV_KIND_ARRAY);
*var = jv_array_append(*var, v);
break;
}
case INSERT: {
jv stktop = stack_pop(jq);
jv v = stack_pop(jq);
jv k = stack_pop(jq);
jv objv = stack_pop(jq);
assert(jv_get_kind(objv) == JV_KIND_OBJECT);
if (jv_get_kind(k) == JV_KIND_STRING) {
stack_push(jq, jv_object_set(objv, k, v));
stack_push(jq, stktop);
} else {
print_error(jq, jv_invalid_with_msg(jv_string_fmt("Cannot use %s as object key",
jv_kind_name(jv_get_kind(k)))));
jv_free(stktop);
jv_free(v);
jv_free(k);
jv_free(objv);
goto do_backtrack;
}
break;
}
case ON_BACKTRACK(RANGE):
case RANGE: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
jv max = stack_pop(jq);
if (jv_get_kind(*var) != JV_KIND_NUMBER ||
jv_get_kind(max) != JV_KIND_NUMBER) {
print_error(jq, jv_invalid_with_msg(jv_string_fmt("Range bounds must be numeric")));
jv_free(max);
goto do_backtrack;
} else if (jv_number_value(jv_copy(*var)) >= jv_number_value(jv_copy(max))) {
/* finished iterating */
goto do_backtrack;
} else {
jv curr = jv_copy(*var);
*var = jv_number(jv_number_value(*var) + 1);
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, jv_copy(max));
stack_save(jq, pc - 3, spos);
stack_push(jq, curr);
}
break;
}
// FIXME: loadv/storev may do too much copying/freeing
case LOADV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(*var), 0);
printf("\n");
}
jv_free(stack_pop(jq));
stack_push(jq, jv_copy(*var));
break;
}
// Does a load but replaces the variable with null
case LOADVN: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(*var), 0);
printf("\n");
}
jv_free(stack_pop(jq));
stack_push(jq, *var);
*var = jv_null();
break;
}
case STOREV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
jv* var = frame_local_var(jq, v, level);
jv val = stack_pop(jq);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(val), 0);
printf("\n");
}
jv_free(*var);
*var = val;
break;
}
case PATH_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jq->path);
stack_save(jq, pc - 1, stack_get_pos(jq));
stack_push(jq, jv_number(jq->subexp_nest));
stack_push(jq, v);
jq->path = jv_array();
jq->subexp_nest = 0;
break;
}
case PATH_END: {
jv v = stack_pop(jq);
jv_free(v); // discard value, only keep path
int old_subexp_nest = (int)jv_number_value(stack_pop(jq));
jv path = jq->path;
jq->path = stack_pop(jq);
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, jv_copy(path));
stack_save(jq, pc - 1, spos);
stack_push(jq, path);
jq->subexp_nest = old_subexp_nest;
break;
}
case ON_BACKTRACK(PATH_BEGIN):
case ON_BACKTRACK(PATH_END): {
jv_free(jq->path);
jq->path = stack_pop(jq);
goto do_backtrack;
}
case INDEX:
case INDEX_OPT: {
jv t = stack_pop(jq);
jv k = stack_pop(jq);
path_append(jq, jv_copy(k));
jv v = jv_get(t, k);
if (jv_is_valid(v)) {
stack_push(jq, v);
} else {
if (opcode == INDEX)
print_error(jq, v);
else
jv_free(v);
goto do_backtrack;
}
break;
}
case JUMP: {
uint16_t offset = *pc++;
pc += offset;
break;
}
case JUMP_F: {
uint16_t offset = *pc++;
jv t = stack_pop(jq);
jv_kind kind = jv_get_kind(t);
if (kind == JV_KIND_FALSE || kind == JV_KIND_NULL) {
pc += offset;
}
stack_push(jq, t); // FIXME do this better
break;
}
case EACH:
case EACH_OPT:
stack_push(jq, jv_number(-1));
// fallthrough
case ON_BACKTRACK(EACH):
case ON_BACKTRACK(EACH_OPT): {
int idx = jv_number_value(stack_pop(jq));
jv container = stack_pop(jq);
int keep_going, is_last = 0;
jv key, value;
if (jv_get_kind(container) == JV_KIND_ARRAY) {
if (opcode == EACH || opcode == EACH_OPT) idx = 0;
else idx = idx + 1;
int len = jv_array_length(jv_copy(container));
keep_going = idx < len;
is_last = idx == len - 1;
if (keep_going) {
key = jv_number(idx);
value = jv_array_get(jv_copy(container), idx);
}
} else if (jv_get_kind(container) == JV_KIND_OBJECT) {
if (opcode == EACH || opcode == EACH_OPT) idx = jv_object_iter(container);
else idx = jv_object_iter_next(container, idx);
keep_going = jv_object_iter_valid(container, idx);
if (keep_going) {
key = jv_object_iter_key(container, idx);
value = jv_object_iter_value(container, idx);
}
} else {
assert(opcode == EACH || opcode == EACH_OPT);
if (opcode == EACH) {
print_error(jq,
jv_invalid_with_msg(jv_string_fmt("Cannot iterate over %s",
jv_kind_name(jv_get_kind(container)))));
}
keep_going = 0;
}
if (!keep_going) {
jv_free(container);
goto do_backtrack;
} else if (is_last) {
// we don't need to make a backtrack point
jv_free(container);
path_append(jq, key);
stack_push(jq, value);
} else {
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, container);
stack_push(jq, jv_number(idx));
stack_save(jq, pc - 1, spos);
path_append(jq, key);
stack_push(jq, value);
}
break;
}
do_backtrack:
case BACKTRACK: {
pc = stack_restore(jq);
if (!pc) {
return jv_invalid();
}
backtracking = 1;
break;
}
case FORK: {
stack_save(jq, pc - 1, stack_get_pos(jq));
pc++; // skip offset this time
break;
}
case ON_BACKTRACK(FORK): {
uint16_t offset = *pc++;
pc += offset;
break;
}
case CALL_BUILTIN: {
int nargs = *pc++;
jv top = stack_pop(jq);
jv* in = cfunc_input;
int i;
in[0] = top;
for (i = 1; i < nargs; i++) {
in[i] = stack_pop(jq);
}
struct cfunction* function = &frame_current(jq)->bc->globals->cfunctions[*pc++];
typedef jv (*func_1)(jv);
typedef jv (*func_2)(jv,jv);
typedef jv (*func_3)(jv,jv,jv);
typedef jv (*func_4)(jv,jv,jv,jv);
typedef jv (*func_5)(jv,jv,jv,jv,jv);
switch (function->nargs) {
case 1: top = ((func_1)function->fptr)(in[0]); break;
case 2: top = ((func_2)function->fptr)(in[0], in[1]); break;
case 3: top = ((func_3)function->fptr)(in[0], in[1], in[2]); break;
case 4: top = ((func_4)function->fptr)(in[0], in[1], in[2], in[3]); break;
case 5: top = ((func_5)function->fptr)(in[0], in[1], in[2], in[3], in[4]); break;
default: return jv_invalid_with_msg(jv_string("Function takes too many arguments"));
}
if (jv_is_valid(top)) {
stack_push(jq, top);
} else {
print_error(jq, top);
goto do_backtrack;
}
break;
}
case CALL_JQ: {
jv input = stack_pop(jq);
uint16_t nclosures = *pc++;
uint16_t* retaddr = pc + 2 + nclosures*2;
struct frame* new_frame = frame_push(jq, make_closure(jq, pc),
pc + 2, nclosures);
new_frame->retdata = jq->stk_top;
new_frame->retaddr = retaddr;
pc = new_frame->bc->code;
stack_push(jq, input);
break;
}
case RET: {
jv value = stack_pop(jq);
assert(jq->stk_top == frame_current(jq)->retdata);
uint16_t* retaddr = frame_current(jq)->retaddr;
if (retaddr) {
// function return
pc = retaddr;
frame_pop(jq);
} else {
// top-level return, yielding value
struct stack_pos spos = stack_get_pos(jq);
stack_push(jq, jv_null());
stack_save(jq, pc - 1, spos);
return value;
}
stack_push(jq, value);
break;
}
case ON_BACKTRACK(RET): {
// resumed after top-level return
goto do_backtrack;
}
}
}
}
jv jq_next(jq_state *jq) {
jv cfunc_input[MAX_CFUNCTION_ARGS];
uint16_t* pc = stack_restore(jq);
assert(pc);
int backtracking = !jq->initial_execution;
jq->initial_execution = 0;
while (1) {
uint16_t opcode = *pc;
if (jq->debug_trace_enabled) {
dump_operation(frame_current_bytecode(&jq->frame_stk), pc);
printf("\t");
const struct opcode_description* opdesc = opcode_describe(opcode);
data_stk_elem* param = 0;
int stack_in = opdesc->stack_in;
if (stack_in == -1) stack_in = pc[1];
for (int i=0; i<stack_in; i++) {
if (i == 0) {
param = forkable_stack_peek(&jq->data_stk);
} else {
printf(" | ");
param = forkable_stack_peek_next(&jq->data_stk, param);
}
if (!param) break;
jv_dump(jv_copy(param->val), 0);
//printf("<%d>", jv_get_refcnt(param->val));
//printf(" -- ");
//jv_dump(jv_copy(jq->path), 0);
}
if (backtracking) printf("\t<backtracking>");
printf("\n");
}
if (backtracking) {
opcode = ON_BACKTRACK(opcode);
backtracking = 0;
}
pc++;
switch (opcode) {
default: assert(0 && "invalid instruction");
case LOADK: {
jv v = jv_array_get(jv_copy(frame_current_bytecode(&jq->frame_stk)->constants), *pc++);
assert(jv_is_valid(v));
jv_free(stack_pop(jq));
stack_push(jq, v);
break;
}
case DUP: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
break;
}
case DUP2: {
jv keep = stack_pop(jq);
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, keep);
stack_push(jq, v);
break;
}
case SUBEXP_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jv_copy(v));
stack_push(jq, v);
jq->subexp_nest++;
break;
}
case SUBEXP_END: {
assert(jq->subexp_nest > 0);
jq->subexp_nest--;
jv a = stack_pop(jq);
jv b = stack_pop(jq);
stack_push(jq, a);
stack_push(jq, b);
break;
}
case POP: {
jv_free(stack_pop(jq));
break;
}
case APPEND: {
jv v = stack_pop(jq);
uint16_t level = *pc++;
uint16_t vidx = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, vidx);
assert(jv_get_kind(*var) == JV_KIND_ARRAY);
*var = jv_array_append(*var, v);
break;
}
case INSERT: {
jv stktop = stack_pop(jq);
jv v = stack_pop(jq);
jv k = stack_pop(jq);
jv objv = stack_pop(jq);
assert(jv_get_kind(objv) == JV_KIND_OBJECT);
if (jv_get_kind(k) == JV_KIND_STRING) {
stack_push(jq, jv_object_set(objv, k, v));
stack_push(jq, stktop);
} else {
print_error(jv_invalid_with_msg(jv_string_fmt("Cannot use %s as object key",
jv_kind_name(jv_get_kind(k)))));
jv_free(stktop);
jv_free(v);
jv_free(k);
jv_free(objv);
goto do_backtrack;
}
break;
}
case ON_BACKTRACK(RANGE):
case RANGE: {
uint16_t level = *pc++;
uint16_t v = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, v);
jv max = stack_pop(jq);
if (jv_get_kind(*var) != JV_KIND_NUMBER ||
jv_get_kind(max) != JV_KIND_NUMBER) {
print_error(jv_invalid_with_msg(jv_string_fmt("Range bounds must be numeric")));
jv_free(max);
goto do_backtrack;
} else if (jv_number_value(jv_copy(*var)) >= jv_number_value(jv_copy(max))) {
/* finished iterating */
goto do_backtrack;
} else {
jv curr = jv_copy(*var);
*var = jv_number(jv_number_value(*var) + 1);
stack_save(jq, pc - 3);
stack_push(jq, jv_copy(max));
stack_switch(jq);
stack_push(jq, curr);
}
break;
}
// FIXME: loadv/storev may do too much copying/freeing
case LOADV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, v);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(*var), 0);
printf("\n");
}
jv_free(stack_pop(jq));
stack_push(jq, jv_copy(*var));
break;
}
case STOREV: {
uint16_t level = *pc++;
uint16_t v = *pc++;
frame_ptr fp = frame_get_level(&jq->frame_stk, frame_current(&jq->frame_stk), level);
jv* var = frame_local_var(fp, v);
jv val = stack_pop(jq);
if (jq->debug_trace_enabled) {
printf("V%d = ", v);
jv_dump(jv_copy(val), 0);
printf("\n");
}
jv_free(*var);
*var = val;
break;
}
case PATH_BEGIN: {
jv v = stack_pop(jq);
stack_push(jq, jq->path);
stack_save(jq, pc - 1);
stack_switch(jq);
stack_push(jq, jv_number(jq->subexp_nest));
stack_push(jq, v);
jq->path = jv_array();
jq->subexp_nest = 0;
break;
}
case PATH_END: {
jv v = stack_pop(jq);
jv_free(v); // discard value, only keep path
int old_subexp_nest = (int)jv_number_value(stack_pop(jq));
jv path = jq->path;
jq->path = stack_pop(jq);
stack_save(jq, pc - 1);
stack_push(jq, jv_copy(path));
stack_switch(jq);
stack_push(jq, path);
jq->subexp_nest = old_subexp_nest;
break;
}
case ON_BACKTRACK(PATH_BEGIN):
case ON_BACKTRACK(PATH_END): {
jv_free(jq->path);
jq->path = stack_pop(jq);
goto do_backtrack;
}
case INDEX: {
jv t = stack_pop(jq);
jv k = stack_pop(jq);
path_append(jq, jv_copy(k));
jv v = jv_get(t, k);
if (jv_is_valid(v)) {
stack_push(jq, v);
} else {
print_error(v);
goto do_backtrack;
}
break;
}
case JUMP: {
uint16_t offset = *pc++;
pc += offset;
break;
}
case JUMP_F: {
uint16_t offset = *pc++;
jv t = stack_pop(jq);
jv_kind kind = jv_get_kind(t);
if (kind == JV_KIND_FALSE || kind == JV_KIND_NULL) {
pc += offset;
}
stack_push(jq, t); // FIXME do this better
break;
}
case EACH:
stack_push(jq, jv_number(-1));
// fallthrough
case ON_BACKTRACK(EACH): {
int idx = jv_number_value(stack_pop(jq));
jv container = stack_pop(jq);
int keep_going;
jv key, value;
if (jv_get_kind(container) == JV_KIND_ARRAY) {
if (opcode == EACH) idx = 0;
else idx = idx + 1;
keep_going = idx < jv_array_length(jv_copy(container));
if (keep_going) {
key = jv_number(idx);
value = jv_array_get(jv_copy(container), idx);
}
} else if (jv_get_kind(container) == JV_KIND_OBJECT) {
if (opcode == EACH) idx = jv_object_iter(container);
else idx = jv_object_iter_next(container, idx);
keep_going = jv_object_iter_valid(container, idx);
if (keep_going) {
key = jv_object_iter_key(container, idx);
value = jv_object_iter_value(container, idx);
}
} else {
assert(opcode == EACH);
print_error(jv_invalid_with_msg(jv_string_fmt("Cannot iterate over %s",
jv_kind_name(jv_get_kind(container)))));
keep_going = 0;
}
if (!keep_going) {
jv_free(container);
goto do_backtrack;
} else {
stack_save(jq, pc - 1);
stack_push(jq, container);
stack_push(jq, jv_number(idx));
stack_switch(jq);
path_append(jq, key);
stack_push(jq, value);
}
break;
}
do_backtrack:
case BACKTRACK: {
pc = stack_restore(jq);
if (!pc) {
return jv_invalid();
}
backtracking = 1;
break;
}
case FORK: {
stack_save(jq, pc - 1);
stack_switch(jq);
pc++; // skip offset this time
break;
}
case ON_BACKTRACK(FORK): {
uint16_t offset = *pc++;
pc += offset;
break;
}
case CALL_BUILTIN: {
int nargs = *pc++;
jv top = stack_pop(jq);
cfunc_input[0] = top;
for (int i = 1; i < nargs; i++) {
cfunc_input[i] = stack_pop(jq);
}
struct cfunction* func = &frame_current_bytecode(&jq->frame_stk)->globals->cfunctions[*pc++];
top = cfunction_invoke(func, cfunc_input);
if (jv_is_valid(top)) {
stack_push(jq, top);
} else {
print_error(top);
goto do_backtrack;
}
break;
}
case CALL_JQ: {
uint16_t nclosures = *pc++;
uint16_t* retaddr = pc + 2 + nclosures*2;
frame_ptr new_frame = frame_push(&jq->frame_stk,
make_closure(&jq->frame_stk, frame_current(&jq->frame_stk), pc),
retaddr);
pc += 2;
frame_ptr old_frame = forkable_stack_peek_next(&jq->frame_stk, new_frame);
assert(nclosures == frame_self(new_frame)->bc->nclosures);
for (int i=0; i<nclosures; i++) {
*frame_closure_arg(new_frame, i) = make_closure(&jq->frame_stk, old_frame, pc);
pc += 2;
}
pc = frame_current_bytecode(&jq->frame_stk)->code;
break;
}
case RET: {
uint16_t* retaddr = *frame_current_retaddr(&jq->frame_stk);
if (retaddr) {
// function return
pc = retaddr;
frame_pop(&jq->frame_stk);
} else {
// top-level return, yielding value
jv value = stack_pop(jq);
stack_save(jq, pc - 1);
stack_push(jq, jv_null());
stack_switch(jq);
return value;
}
break;
}
case ON_BACKTRACK(RET): {
// resumed after top-level return
goto do_backtrack;
}
}
}
}