diff options
Diffstat (limited to 'eval.cpp')
| -rw-r--r-- | eval.cpp | 27 |
1 files changed, 14 insertions, 13 deletions
@@ -117,27 +117,26 @@ inline bool make_exec(Pair *ptr) { return ptr->cdr == empty_list; } -inline void push(Pair * &pc, EvalObj ** &top_ptr, Environment * &envt, Continuation * &cont) { -// if (pc->car == NULL) - // puts("oops"); +inline void push(Pair * &pc, EvalObj ** &top_ptr, + Environment * &envt, Continuation * &cont) { if (pc->car->is_simple_obj()) // Not an opt invocation { *top_ptr++ = gc.attach(envt->get_obj(pc->car)); // Objectify the symbol pc = pc->next; // Move to the next instruction -// if (pc == empty_list) -// puts("oops"); } else // Operational Invocation { if (pc->car == empty_list) throw NormalError(SYN_ERR_EMPTY_COMB); - gc.expose(cont); - cont = new Continuation(envt, pc, cont); - gc.attach(cont); - - *top_ptr++ = gc.attach(cont); - + if (!cont->tail) // a normal invocation + { + gc.expose(cont); + cont = new Continuation(envt, pc, cont); + gc.attach(cont); + *top_ptr++ = gc.attach(cont); + } + else cont->tail = false; if (!make_exec(TO_PAIR(pc->car))) throw TokenError(pc->car->ext_repr(), RUN_ERR_WRONG_NUM_OF_ARGS); @@ -150,7 +149,9 @@ inline void push(Pair * &pc, EvalObj ** &top_ptr, Environment * &envt, Continuat EvalObj *Evaluator::run_expr(Pair *prog) { EvalObj **top_ptr = eval_stack; Pair *pc = prog; - Continuation *cont = NULL; + Continuation *bcont = new Continuation(NULL, NULL, NULL), // dummy cont + *cont = bcont; + gc.attach(cont); #ifdef GC_DEBUG fprintf(stderr, "Start the evaluation...\n"); #endif @@ -158,7 +159,7 @@ EvalObj *Evaluator::run_expr(Pair *prog) { push(pc, top_ptr, envt, cont); gc.attach(prog); - while (cont) + while (cont != bcont) { if (top_ptr == eval_stack + EVAL_STACK_SIZE) throw TokenError("Evaluation", RUN_ERR_STACK_OVERFLOW); |