static SCM eval (SCM x, SCM env) { SCM mx; SCM proc = SCM_UNDEFINED, args = SCM_EOL; unsigned int argc; loop: SCM_TICK; if (!SCM_MEMOIZED_P (x)) abort (); mx = SCM_MEMOIZED_ARGS (x); switch (SCM_MEMOIZED_TAG (x)) { case SCM_M_SEQ: eval (CAR (mx), env); x = CDR (mx); goto loop; case SCM_M_IF: if (scm_is_true (EVAL1 (CAR (mx), env))) x = CADR (mx); else x = CDDR (mx); goto loop; case SCM_M_LET: { SCM inits = CAR (mx); SCM new_env = CAPTURE_ENV (env); for (; scm_is_pair (inits); inits = CDR (inits)) new_env = scm_cons (EVAL1 (CAR (inits), env), new_env); env = new_env; x = CDR (mx); goto loop; } case SCM_M_LAMBDA: RETURN_BOOT_CLOSURE (mx, CAPTURE_ENV (env)); case SCM_M_QUOTE: return mx; case SCM_M_DEFINE: scm_define (CAR (mx), EVAL1 (CDR (mx), env)); return SCM_UNSPECIFIED; case SCM_M_DYNWIND: { SCM in, out, res; scm_i_thread *t = SCM_I_CURRENT_THREAD; in = EVAL1 (CAR (mx), env); out = EVAL1 (CDDR (mx), env); scm_call_0 (in); scm_dynstack_push_dynwind (&t->dynstack, in, out); res = eval (CADR (mx), env); scm_dynstack_pop (&t->dynstack); scm_call_0 (out); return res; } case SCM_M_WITH_FLUIDS: { long i, len; SCM *fluidv, *valuesv, walk, res; scm_i_thread *thread = SCM_I_CURRENT_THREAD; len = scm_ilength (CAR (mx)); fluidv = alloca (sizeof (SCM)*len); for (i = 0, walk = CAR (mx); i < len; i++, walk = CDR (walk)) fluidv[i] = EVAL1 (CAR (walk), env); valuesv = alloca (sizeof (SCM)*len); for (i = 0, walk = CADR (mx); i < len; i++, walk = CDR (walk)) valuesv[i] = EVAL1 (CAR (walk), env); scm_dynstack_push_fluids (&thread->dynstack, len, fluidv, valuesv, thread->dynamic_state); res = eval (CDDR (mx), env); scm_dynstack_unwind_fluids (&thread->dynstack, thread->dynamic_state); return res; } case SCM_M_APPLY: /* Evaluate the procedure to be applied. */ proc = EVAL1 (CAR (mx), env); /* Evaluate the argument holding the list of arguments */ args = EVAL1 (CADR (mx), env); apply_proc: /* Go here to tail-apply a procedure. PROC is the procedure and * ARGS is the list of arguments. */ if (BOOT_CLOSURE_P (proc)) { prepare_boot_closure_env_for_apply (proc, args, &x, &env); goto loop; } else return scm_call_with_vm (scm_the_vm (), proc, args); case SCM_M_CALL: /* Evaluate the procedure to be applied. */ proc = EVAL1 (CAR (mx), env); argc = SCM_I_INUM (CADR (mx)); mx = CDDR (mx); if (BOOT_CLOSURE_P (proc)) { prepare_boot_closure_env_for_eval (proc, argc, mx, &x, &env); goto loop; } else { SCM *argv; unsigned int i; argv = alloca (argc * sizeof (SCM)); for (i = 0; i < argc; i++, mx = CDR (mx)) argv[i] = EVAL1 (CAR (mx), env); return scm_c_vm_run (scm_the_vm (), proc, argv, argc); } case SCM_M_CONT: return scm_i_call_with_current_continuation (EVAL1 (mx, env)); case SCM_M_CALL_WITH_VALUES: { SCM producer; SCM v; producer = EVAL1 (CAR (mx), env); /* `proc' is the consumer. */ proc = EVAL1 (CDR (mx), env); v = scm_call_with_vm (scm_the_vm (), producer, SCM_EOL); if (SCM_VALUESP (v)) args = scm_struct_ref (v, SCM_INUM0); else args = scm_list_1 (v); goto apply_proc; } case SCM_M_LEXICAL_REF: { int n; SCM ret; for (n = SCM_I_INUM (mx); n; n--) env = CDR (env); ret = CAR (env); if (SCM_UNLIKELY (SCM_UNBNDP (ret))) /* we don't know what variable, though, because we don't have its name */ error_used_before_defined (); return ret; } case SCM_M_LEXICAL_SET: { int n; SCM val = EVAL1 (CDR (mx), env); for (n = SCM_I_INUM (CAR (mx)); n; n--) env = CDR (env); SCM_SETCAR (env, val); return SCM_UNSPECIFIED; } case SCM_M_TOPLEVEL_REF: if (SCM_VARIABLEP (mx)) return SCM_VARIABLE_REF (mx); else { while (scm_is_pair (env)) env = CDR (env); return SCM_VARIABLE_REF (scm_memoize_variable_access_x (x, CAPTURE_ENV (env))); } case SCM_M_TOPLEVEL_SET: { SCM var = CAR (mx); SCM val = EVAL1 (CDR (mx), env); if (SCM_VARIABLEP (var)) { SCM_VARIABLE_SET (var, val); return SCM_UNSPECIFIED; } else { while (scm_is_pair (env)) env = CDR (env); SCM_VARIABLE_SET (scm_memoize_variable_access_x (x, CAPTURE_ENV (env)), val); return SCM_UNSPECIFIED; } } case SCM_M_MODULE_REF: if (SCM_VARIABLEP (mx)) return SCM_VARIABLE_REF (mx); else return SCM_VARIABLE_REF (scm_memoize_variable_access_x (x, SCM_BOOL_F)); case SCM_M_MODULE_SET: if (SCM_VARIABLEP (CDR (mx))) { SCM_VARIABLE_SET (CDR (mx), EVAL1 (CAR (mx), env)); return SCM_UNSPECIFIED; } else { SCM_VARIABLE_SET (scm_memoize_variable_access_x (x, SCM_BOOL_F), EVAL1 (CAR (mx), env)); return SCM_UNSPECIFIED; } case SCM_M_PROMPT: { SCM vm, k, res; scm_i_jmp_buf registers; /* We need the handler after nonlocal return to the setjmp, so make sure it is volatile. */ volatile SCM handler; k = EVAL1 (CAR (mx), env); handler = EVAL1 (CDDR (mx), env); vm = scm_the_vm (); /* Push the prompt onto the dynamic stack. */ scm_dynstack_push_prompt (&SCM_I_CURRENT_THREAD->dynstack, SCM_F_DYNSTACK_PROMPT_ESCAPE_ONLY, k, SCM_VM_DATA (vm)->fp, SCM_VM_DATA (vm)->sp, SCM_VM_DATA (vm)->ip, ®isters); if (SCM_I_SETJMP (registers)) { /* The prompt exited nonlocally. */ proc = handler; args = scm_i_prompt_pop_abort_args_x (scm_the_vm ()); goto apply_proc; } res = eval (CADR (mx), env); scm_dynstack_pop (&SCM_I_CURRENT_THREAD->dynstack); return res; } default: abort (); } }
static SCM eval (SCM x, SCM env) { SCM mx; SCM proc = SCM_UNDEFINED, args = SCM_EOL; unsigned int argc; loop: SCM_TICK; mx = SCM_MEMOIZED_ARGS (x); switch (SCM_I_INUM (SCM_CAR (x))) { case SCM_M_SEQ: eval (CAR (mx), env); x = CDR (mx); goto loop; case SCM_M_IF: if (scm_is_true (EVAL1 (CAR (mx), env))) x = CADR (mx); else x = CDDR (mx); goto loop; case SCM_M_LET: { SCM inits = CAR (mx); SCM new_env; int i; new_env = make_env (VECTOR_LENGTH (inits), SCM_UNDEFINED, env); for (i = 0; i < VECTOR_LENGTH (inits); i++) env_set (new_env, 0, i, EVAL1 (VECTOR_REF (inits, i), env)); env = new_env; x = CDR (mx); goto loop; } case SCM_M_LAMBDA: RETURN_BOOT_CLOSURE (mx, env); case SCM_M_CAPTURE_ENV: { SCM locs = CAR (mx); SCM new_env; int i; new_env = make_env (VECTOR_LENGTH (locs), SCM_BOOL_F, env); for (i = 0; i < VECTOR_LENGTH (locs); i++) { SCM loc = VECTOR_REF (locs, i); int depth, width; depth = SCM_I_INUM (CAR (loc)); width = SCM_I_INUM (CDR (loc)); env_set (new_env, 0, i, env_ref (env, depth, width)); } env = new_env; x = CDR (mx); goto loop; } case SCM_M_QUOTE: return mx; case SCM_M_CAPTURE_MODULE: return eval (mx, scm_current_module ()); case SCM_M_APPLY: /* Evaluate the procedure to be applied. */ proc = EVAL1 (CAR (mx), env); /* Evaluate the argument holding the list of arguments */ args = EVAL1 (CADR (mx), env); apply_proc: /* Go here to tail-apply a procedure. PROC is the procedure and * ARGS is the list of arguments. */ if (BOOT_CLOSURE_P (proc)) { prepare_boot_closure_env_for_apply (proc, args, &x, &env); goto loop; } else return scm_apply_0 (proc, args); case SCM_M_CALL: /* Evaluate the procedure to be applied. */ proc = EVAL1 (CAR (mx), env); argc = scm_ilength (CDR (mx)); mx = CDR (mx); if (BOOT_CLOSURE_P (proc)) { prepare_boot_closure_env_for_eval (proc, argc, mx, &x, &env); goto loop; } else { SCM *argv; unsigned int i; argv = alloca (argc * sizeof (SCM)); for (i = 0; i < argc; i++, mx = CDR (mx)) argv[i] = EVAL1 (CAR (mx), env); return scm_call_n (proc, argv, argc); } case SCM_M_CONT: return scm_i_call_with_current_continuation (EVAL1 (mx, env)); case SCM_M_CALL_WITH_VALUES: { SCM producer; SCM v; producer = EVAL1 (CAR (mx), env); /* `proc' is the consumer. */ proc = EVAL1 (CDR (mx), env); v = scm_call_0 (producer); if (SCM_VALUESP (v)) args = scm_struct_ref (v, SCM_INUM0); else args = scm_list_1 (v); goto apply_proc; } case SCM_M_LEXICAL_REF: { SCM pos; int depth, width; pos = mx; depth = SCM_I_INUM (CAR (pos)); width = SCM_I_INUM (CDR (pos)); return env_ref (env, depth, width); } case SCM_M_LEXICAL_SET: { SCM pos; int depth, width; SCM val = EVAL1 (CDR (mx), env); pos = CAR (mx); depth = SCM_I_INUM (CAR (pos)); width = SCM_I_INUM (CDR (pos)); env_set (env, depth, width, val); return SCM_UNSPECIFIED; } case SCM_M_BOX_REF: { SCM box = mx; return scm_variable_ref (EVAL1 (box, env)); } case SCM_M_BOX_SET: { SCM box = CAR (mx), val = CDR (mx); return scm_variable_set_x (EVAL1 (box, env), EVAL1 (val, env)); } case SCM_M_RESOLVE: if (SCM_VARIABLEP (mx)) return mx; else { SCM var; var = scm_sys_resolve_variable (mx, env_tail (env)); scm_set_cdr_x (x, var); return var; } case SCM_M_CALL_WITH_PROMPT: { struct scm_vm *vp; SCM k, handler, res; scm_i_jmp_buf registers; scm_t_ptrdiff saved_stack_depth; k = EVAL1 (CAR (mx), env); handler = EVAL1 (CDDR (mx), env); vp = scm_the_vm (); saved_stack_depth = vp->stack_top - vp->sp; /* Push the prompt onto the dynamic stack. */ scm_dynstack_push_prompt (&SCM_I_CURRENT_THREAD->dynstack, SCM_F_DYNSTACK_PROMPT_ESCAPE_ONLY, k, vp->stack_top - vp->fp, saved_stack_depth, vp->ip, ®isters); if (SCM_I_SETJMP (registers)) { /* The prompt exited nonlocally. */ scm_gc_after_nonlocal_exit (); proc = handler; args = scm_i_prompt_pop_abort_args_x (vp, saved_stack_depth); goto apply_proc; } res = scm_call_0 (eval (CADR (mx), env)); scm_dynstack_pop (&SCM_I_CURRENT_THREAD->dynstack); return res; } default: abort (); } }