/* function.c QC function support code Copyright (C) 2002 Bill Currie Author: Bill Currie Date: 2002/5/7 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to: Free Software Foundation, Inc. 59 Temple Place - Suite 330 Boston, MA 02111-1307, USA */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #ifdef HAVE_STRING_H # include #endif #ifdef HAVE_STRINGS_H # include #endif #include #include "QF/alloc.h" #include "QF/dstring.h" #include "QF/hash.h" #include "QF/va.h" #include "tools/qfcc/include/qfcc.h" #include "tools/qfcc/include/class.h" #include "tools/qfcc/include/codespace.h" #include "tools/qfcc/include/debug.h" #include "tools/qfcc/include/def.h" #include "tools/qfcc/include/defspace.h" #include "tools/qfcc/include/diagnostic.h" #include "tools/qfcc/include/emit.h" #include "tools/qfcc/include/expr.h" #include "tools/qfcc/include/flow.h" #include "tools/qfcc/include/function.h" #include "tools/qfcc/include/opcodes.h" #include "tools/qfcc/include/options.h" #include "tools/qfcc/include/reloc.h" #include "tools/qfcc/include/shared.h" #include "tools/qfcc/include/statements.h" #include "tools/qfcc/include/strpool.h" #include "tools/qfcc/include/symtab.h" #include "tools/qfcc/include/type.h" #include "tools/qfcc/include/value.h" static param_t *params_freelist; static function_t *functions_freelist; static hashtab_t *overloaded_functions; static hashtab_t *function_map; // standardized base register to use for all locals (arguments, local defs, // params) #define LOCALS_REG 1 static const char * ol_func_get_key (const void *_f, void *unused) { overloaded_function_t *f = (overloaded_function_t *) _f; return f->full_name; } static const char * func_map_get_key (const void *_f, void *unused) { overloaded_function_t *f = (overloaded_function_t *) _f; return f->name; } param_t * new_param (const char *selector, type_t *type, const char *name) { param_t *param; ALLOC (4096, param_t, params, param); param->next = 0; param->selector = selector; param->type = type; param->name = name; return param; } param_t * param_append_identifiers (param_t *params, symbol_t *idents, type_t *type) { param_t **p = ¶ms; while (*p) p = &(*p)->next; if (!idents) { *p = new_param (0, 0, 0); p = &(*p)->next; } while (idents) { idents->type = type; *p = new_param (0, type, idents->name); (*p)->symbol = idents; p = &(*p)->next; idents = idents->next; } return params; } static param_t * _reverse_params (param_t *params, param_t *next) { param_t *p = params; if (params->next) p = _reverse_params (params->next, params); params->next = next; return p; } param_t * reverse_params (param_t *params) { if (!params) return 0; return _reverse_params (params, 0); } param_t * append_params (param_t *params, param_t *more_params) { if (params) { param_t *p; for (p = params; p->next; ) { p = p->next; } p->next = more_params; return params; } return more_params; } param_t * copy_params (param_t *params) { param_t *n_parms = 0, **p = &n_parms; while (params) { *p = new_param (params->selector, params->type, params->name); params = params->next; p = &(*p)->next; } return n_parms; } type_t * parse_params (type_t *type, param_t *parms) { param_t *p; type_t *new; type_t *ptype; int count = 0; if (type && is_class (type)) { error (0, "cannot return an object (forgot *?)"); type = &type_id; } new = new_type (); new->type = ev_func; new->alignment = 1; new->t.func.type = type; new->t.func.num_params = 0; for (p = parms; p; p = p->next) { if (p->type) { count++; } } if (count) { new->t.func.param_types = malloc (count * sizeof (type_t)); } for (p = parms; p; p = p->next) { if (!p->selector && !p->type && !p->name) { if (p->next) internal_error (0, 0); new->t.func.num_params = -(new->t.func.num_params + 1); } else if (p->type) { if (is_class (p->type)) { error (0, "cannot use an object as a parameter (forgot *?)"); p->type = &type_id; } ptype = (type_t *) unalias_type (p->type); //FIXME cast new->t.func.param_types[new->t.func.num_params] = ptype; new->t.func.num_params++; } } return new; } param_t * check_params (param_t *params) { int num = 1; param_t *p = params; if (!params) return 0; while (p) { if (p->type && is_void(p->type)) { if (p->name) { error (0, "parameter %d ('%s') has incomplete type", num, p->name); p->type = type_default; } else if (num > 1 || p->next) { error (0, "'void' must be the only parameter"); p->name = "void"; } else { // this is a void function return 0; } } p = p->next; } return params; } static overloaded_function_t * get_function (const char *name, const type_t *type, int overload, int create) { const char *full_name; overloaded_function_t *func; if (!overloaded_functions) { overloaded_functions = Hash_NewTable (1021, ol_func_get_key, 0, 0, 0); function_map = Hash_NewTable (1021, func_map_get_key, 0, 0, 0); } name = save_string (name); full_name = save_string (va (0, "%s|%s", name, encode_params (type))); func = Hash_Find (overloaded_functions, full_name); if (func) { if (func->type != type) { error (0, "can't overload on return types"); return func; } return func; } if (!create) return 0; func = Hash_Find (function_map, name); if (func) { if (!overload && !func->overloaded) { expr_t *e = new_expr (); e->line = func->line; e->file = func->file; warning (0, "creating overloaded function %s without @overload", full_name); warning (e, "(previous function is %s)", func->full_name); } overload = 1; } func = calloc (1, sizeof (overloaded_function_t)); func->name = name; func->full_name = full_name; func->type = type; func->overloaded = overload; func->file = pr.source_file; func->line = pr.source_line; Hash_Add (overloaded_functions, func); Hash_Add (function_map, func); return func; } symbol_t * function_symbol (symbol_t *sym, int overload, int create) { const char *name = sym->name; overloaded_function_t *func; symbol_t *s; func = get_function (name, unalias_type (sym->type), overload, create); if (func && func->overloaded) name = func->full_name; s = symtab_lookup (current_symtab, name); if ((!s || s->table != current_symtab) && create) { s = new_symbol (name); s->sy_type = sy_func; s->type = (type_t *) unalias_type (sym->type); // FIXME cast s->params = sym->params; s->s.func = 0; // function not yet defined symtab_addsymbol (current_symtab, s); } return s; } // NOTE sorts the list in /reverse/ order static int func_compare (const void *a, const void *b) { overloaded_function_t *fa = *(overloaded_function_t **) a; overloaded_function_t *fb = *(overloaded_function_t **) b; const type_t *ta = fa->type; const type_t *tb = fb->type; int na = ta->t.func.num_params; int nb = tb->t.func.num_params; int ret, i; if (na < 0) na = ~na; if (nb < 0) nb = ~nb; if (na != nb) return nb - na; if ((ret = (fb->type->t.func.num_params - fa->type->t.func.num_params))) return ret; for (i = 0; i < na && i < nb; i++) if (ta->t.func.param_types[i] != tb->t.func.param_types[i]) return (long)(tb->t.func.param_types[i] - ta->t.func.param_types[i]); return 0; } expr_t * find_function (expr_t *fexpr, expr_t *params) { expr_t *e; int i, j, func_count, parm_count, reported = 0; overloaded_function_t *f, dummy, *best = 0; type_t type; void **funcs, *dummy_p = &dummy; if (fexpr->type != ex_symbol) return fexpr; memset (&type, 0, sizeof (type)); type.type = ev_func; for (e = params; e; e = e->next) { if (e->type == ex_error) return e; type.t.func.num_params++; } i = type.t.func.num_params * sizeof (type_t); type.t.func.param_types = alloca(i); memset (type.t.func.param_types, 0, i); for (i = 0, e = params; e; i++, e = e->next) { type.t.func.param_types[type.t.func.num_params - 1 - i] = get_type (e); if (e->type == ex_error) return e; } funcs = Hash_FindList (function_map, fexpr->e.symbol->name); if (!funcs) return fexpr; for (func_count = 0; funcs[func_count]; func_count++) ; if (func_count < 2) { f = (overloaded_function_t *) funcs[0]; if (func_count && !f->overloaded) { free (funcs); return fexpr; } } type.t.func.type = ((overloaded_function_t *) funcs[0])->type->t.func.type; dummy.type = find_type (&type); qsort (funcs, func_count, sizeof (void *), func_compare); dummy.full_name = save_string (va (0, "%s|%s", fexpr->e.symbol->name, encode_params (&type))); dummy_p = bsearch (&dummy_p, funcs, func_count, sizeof (void *), func_compare); if (dummy_p) { f = (overloaded_function_t *) *(void **) dummy_p; if (f->overloaded) { fexpr->e.symbol = symtab_lookup (current_symtab, f->full_name); if (!fexpr->e.symbol) internal_error (fexpr, "overloaded function %s not found", best->full_name); } free (funcs); return fexpr; } for (i = 0; i < func_count; i++) { f = (overloaded_function_t *) funcs[i]; parm_count = f->type->t.func.num_params; if ((parm_count >= 0 && parm_count != type.t.func.num_params) || (parm_count < 0 && ~parm_count > type.t.func.num_params)) { funcs[i] = 0; continue; } if (parm_count < 0) parm_count = ~parm_count; for (j = 0; j < parm_count; j++) { if (!type_assignable (f->type->t.func.param_types[j], type.t.func.param_types[j])) { funcs[i] = 0; break; } } if (j < parm_count) continue; } for (i = 0; i < func_count; i++) { f = (overloaded_function_t *) funcs[i]; if (f) { if (!best) { best = f; } else { if (!reported) { reported = 1; error (fexpr, "unable to disambiguate %s", dummy.full_name); error (fexpr, "possible match: %s", best->full_name); } error (fexpr, "possible match: %s", f->full_name); } } } if (reported) return fexpr; if (best) { if (best->overloaded) { fexpr->e.symbol = symtab_lookup (current_symtab, best->full_name); if (!fexpr->e.symbol) internal_error (fexpr, "overloaded function %s not found", best->full_name); } free (funcs); return fexpr; } error (fexpr, "unable to find function matching %s", dummy.full_name); free (funcs); return fexpr; } static void check_function (symbol_t *fsym) { param_t *params = fsym->params; param_t *p; int i; if (!type_size (fsym->type->t.func.type)) { error (0, "return type is an incomplete type"); fsym->type->t.func.type = &type_void;//FIXME better type? } if (type_size (fsym->type->t.func.type) > type_size (&type_param)) { error (0, "return value too large to be passed by value (%d)", type_size (&type_param)); fsym->type->t.func.type = &type_void;//FIXME better type? } for (p = params, i = 0; p; p = p->next, i++) { if (!p->selector && !p->type && !p->name) continue; // ellipsis marker if (!p->type) continue; // non-param selector if (!type_size (p->type)) error (0, "parameter %d (ā€˜%sā€™) has incomplete type", i + 1, p->name); if (type_size (p->type) > type_size (&type_param)) error (0, "param %d (ā€˜%sā€™) is too large to be passed by value", i + 1, p->name); } } static void build_v6p_scope (symbol_t *fsym) { int i; param_t *p; symbol_t *args = 0; symbol_t *param; symtab_t *parameters = fsym->s.func->parameters; symtab_t *locals = fsym->s.func->locals; if (fsym->s.func->type->t.func.num_params < 0) { args = new_symbol_type (".args", &type_va_list); initialize_def (args, 0, parameters->space, sc_param, locals); } for (p = fsym->params, i = 0; p; p = p->next) { if (!p->selector && !p->type && !p->name) continue; // ellipsis marker if (!p->type) continue; // non-param selector if (!p->name) { error (0, "parameter name omitted"); p->name = save_string (""); } param = new_symbol_type (p->name, p->type); initialize_def (param, 0, parameters->space, sc_param, locals); i++; } if (args) { while (i < PR_MAX_PARAMS) { param = new_symbol_type (va (0, ".par%d", i), &type_param); initialize_def (param, 0, parameters->space, sc_param, locals); i++; } } } static void create_param (symtab_t *parameters, symbol_t *param) { defspace_t *space = parameters->space; def_t *def = new_def (param->name, 0, space, sc_param); int size = type_size (param->type); int alignment = param->type->alignment; if (alignment < 4) { alignment = 4; } def->offset = defspace_alloc_aligned_highwater (space, size, alignment); def->type = param->type; param->s.def = def; param->sy_type = sy_var; symtab_addsymbol (parameters, param); } static void build_rua_scope (symbol_t *fsym) { for (param_t *p = fsym->params; p; p = p->next) { symbol_t *param; if (!p->selector && !p->type && !p->name) { // ellipsis marker param = new_symbol_type (".args", &type_va_list); } else { if (!p->type) { continue; // non-param selector } if (!p->name) { error (0, "parameter name omitted"); p->name = save_string (""); } param = new_symbol_type (p->name, p->type); } create_param (fsym->s.func->parameters, param); param->s.def->reg = fsym->s.func->temp_reg;; } } static void build_scope (symbol_t *fsym, symtab_t *parent) { symtab_t *parameters; symtab_t *locals; if (!fsym->s.func) { internal_error (0, "function %s not defined", fsym->name); } if (!is_func (fsym->s.func->type)) { internal_error (0, "function type %s not a funciton", fsym->name); } check_function (fsym); fsym->s.func->label_scope = new_symtab (0, stab_local); parameters = new_symtab (parent, stab_local); parameters->space = defspace_new (ds_virtual); fsym->s.func->parameters = parameters; locals = new_symtab (parameters, stab_local); locals->space = defspace_new (ds_virtual); fsym->s.func->locals = locals; if (options.code.progsversion == PROG_VERSION) { build_rua_scope (fsym); } else { build_v6p_scope (fsym); } } function_t * new_function (const char *name, const char *nice_name) { function_t *f; ALLOC (1024, function_t, functions, f); f->s_name = ReuseString (name); f->s_file = pr.source_file; if (!(f->name = nice_name)) f->name = name; return f; } void make_function (symbol_t *sym, const char *nice_name, defspace_t *space, storage_class_t storage) { reloc_t *relocs = 0; if (sym->sy_type != sy_func) internal_error (0, "%s is not a function", sym->name); if (storage == sc_extern && sym->s.func) return; if (!sym->s.func) { sym->s.func = new_function (sym->name, nice_name); sym->s.func->sym = sym; sym->s.func->type = unalias_type (sym->type); } if (sym->s.func->def && sym->s.func->def->external && storage != sc_extern) { //FIXME this really is not the right way relocs = sym->s.func->def->relocs; free_def (sym->s.func->def); sym->s.func->def = 0; } if (!sym->s.func->def) { sym->s.func->def = new_def (sym->name, sym->type, space, storage); reloc_attach_relocs (relocs, &sym->s.func->def->relocs); } } void add_function (function_t *f) { *pr.func_tail = f; pr.func_tail = &f->next; f->function_num = pr.num_functions++; } function_t * begin_function (symbol_t *sym, const char *nicename, symtab_t *parent, int far, storage_class_t storage) { defspace_t *space; if (sym->sy_type != sy_func) { error (0, "%s is not a function", sym->name); sym = new_symbol_type (sym->name, &type_func); sym = function_symbol (sym, 1, 1); } if (sym->s.func && sym->s.func->def && sym->s.func->def->initialized) { error (0, "%s redefined", sym->name); sym = new_symbol_type (sym->name, sym->type); sym = function_symbol (sym, 1, 1); } space = sym->table->space; if (far) space = pr.far_data; make_function (sym, nicename, space, storage); if (!sym->s.func->def->external) { sym->s.func->def->initialized = 1; sym->s.func->def->constant = 1; sym->s.func->def->nosave = 1; add_function (sym->s.func); reloc_def_func (sym->s.func, sym->s.func->def); } sym->s.func->code = pr.code->size; sym->s.func->s_file = pr.source_file; if (options.code.debug) { pr_lineno_t *lineno = new_lineno (); sym->s.func->line_info = lineno - pr.linenos; } build_scope (sym, parent); return sym->s.func; } static void build_function (symbol_t *fsym) { const type_t *func_type = fsym->s.func->type; if (func_type->t.func.num_params > PR_MAX_PARAMS) { error (0, "too many params"); } } static void merge_spaces (defspace_t *dst, defspace_t *src, int alignment) { int offset; for (def_t *def = src->defs; def; def = def->next) { if (def->type->alignment > alignment) { alignment = def->type->alignment; } } offset = defspace_alloc_aligned_highwater (dst, src->size, alignment); for (def_t *def = src->defs; def; def = def->next) { def->offset += offset; def->space = dst; } if (src->defs) { *dst->def_tail = src->defs; dst->def_tail = src->def_tail; src->def_tail = &src->defs; *src->def_tail = 0; } defspace_delete (src); } function_t * build_code_function (symbol_t *fsym, expr_t *state_expr, expr_t *statements) { if (fsym->sy_type != sy_func) // probably in error recovery return 0; build_function (fsym); if (state_expr) { state_expr->next = statements; statements = state_expr; } function_t *func = fsym->s.func; if (options.code.progsversion == PROG_VERSION) { /* Create a function entry block to set up the stack frame and add the * actual function code to that block. This ensure that the adjstk and * with statements always come first, regardless of what ideas the * optimizer gets. */ expr_t *e; expr_t *entry = new_block_expr (); entry->file = func->def->file; entry->line = func->def->line; e = new_adjstk_expr (0, 0); e->file = func->def->file; e->line = func->def->line; append_expr (entry, e); e = new_with_expr (2, LOCALS_REG, new_short_expr (0)); e->file = func->def->file; e->line = func->def->line; append_expr (entry, e); append_expr (entry, statements); statements = entry; /* Mark all local defs as using the base register used for stack * references. */ func->temp_reg = LOCALS_REG; for (def_t *def = func->locals->space->defs; def; def = def->next) { if (def->local || def->param) { def->reg = LOCALS_REG; } } for (def_t *def = func->parameters->space->defs; def; def = def->next) { if (def->local || def->param) { def->reg = LOCALS_REG; } } } emit_function (func, statements); if (options.code.progsversion < PROG_VERSION) { // stitch parameter and locals data together with parameters coming // first defspace_t *space = defspace_new (ds_virtual); func->params_start = 0; merge_spaces (space, func->parameters->space, 1); func->parameters->space = space; merge_spaces (space, func->locals->space, 1); func->locals->space = space; } else { defspace_t *space = defspace_new (ds_virtual); if (func->arguments) { func->arguments->size = func->arguments->max_size; merge_spaces (space, func->arguments, 4); func->arguments = 0; } merge_spaces (space, func->locals->space, 4); func->locals->space = space; // allocate 0 words to force alignment and get the address func->params_start = defspace_alloc_aligned_highwater (space, 0, 4); dstatement_t *st = &pr.code->code[func->code]; if (st->op == OP_ADJSTK) { st->b = -func->params_start; } merge_spaces (space, func->parameters->space, 4); func->parameters->space = space; // force the alignment again so the full stack slot is counted when // the final parameter is smaller than 4 words defspace_alloc_aligned_highwater (space, 0, 4); } return fsym->s.func; } function_t * build_builtin_function (symbol_t *sym, expr_t *bi_val, int far, storage_class_t storage) { int bi; defspace_t *space; if (sym->sy_type != sy_func) { error (bi_val, "%s is not a function", sym->name); return 0; } if (sym->s.func && sym->s.func->def && sym->s.func->def->initialized) { error (bi_val, "%s redefined", sym->name); return 0; } if (!is_int_val (bi_val) && !is_float_val (bi_val)) { error (bi_val, "invalid constant for = #"); return 0; } space = sym->table->space; if (far) space = pr.far_data; make_function (sym, 0, space, storage); if (sym->s.func->def->external) return 0; sym->s.func->def->initialized = 1; sym->s.func->def->constant = 1; sym->s.func->def->nosave = 1; add_function (sym->s.func); if (is_int_val (bi_val)) bi = expr_int (bi_val); else bi = expr_float (bi_val); if (bi < 0) { error (bi_val, "builtin functions must be positive or 0"); return 0; } sym->s.func->builtin = bi; reloc_def_func (sym->s.func, sym->s.func->def); build_function (sym); // for debug info build_scope (sym, current_symtab); sym->s.func->parameters->space->size = 0; sym->s.func->locals->space = sym->s.func->parameters->space; return sym->s.func; } void emit_function (function_t *f, expr_t *e) { if (pr.error_count) return; f->code = pr.code->size; lineno_base = f->def->line; f->sblock = make_statements (e); if (options.code.optimize) { flow_data_flow (f); } else { statements_count_temps (f->sblock); } emit_statements (f->sblock); } int function_parms (function_t *f, byte *parm_size) { int count, i; ty_func_t *func = &f->sym->type->t.func; if (func->num_params >= 0) count = func->num_params; else count = -func->num_params - 1; for (i = 0; i < count; i++) parm_size[i] = type_size (func->param_types[i]); return func->num_params; } void clear_functions (void) { if (overloaded_functions) Hash_FlushTable (overloaded_functions); if (function_map) Hash_FlushTable (function_map); }