From 08fcf7d83c36596660f5841d14052f6f3c46e04d Mon Sep 17 00:00:00 2001 From: Teddy Date: Sat, 12 Apr 2014 15:26:32 +0800 Subject: functions are changed to types --- semantics.c | 100 ++++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 61 insertions(+), 39 deletions(-) diff --git a/semantics.c b/semantics.c index 1ab8376..a403b8a 100644 --- a/semantics.c +++ b/semantics.c @@ -48,9 +48,9 @@ static char err_buff[MAX_ERROR_BUFF]; static CType_t basic_type_int; static CType_t basic_type_char; static CType_t basic_type_void; -static CVar_t builtin_printf; -static CVar_t builtin_scanf; -static CVar_t builtin_malloc; +static CType_t builtin_printf; +static CType_t builtin_scanf; +static CType_t builtin_malloc; static void error_print(CNode *ast, const char *fmt, ...) { va_list args; @@ -730,14 +730,28 @@ CVar_t semantics_decl(CNode *p, CScope_t scope) { { CNode *initr = p->chd->next; CVar_t var = semantics_declr(p->chd, type, scope, 0); - if (scope->lvl && !type_is_complete(var->type)) - ERROR((var->ast, "storage size of '%s' isn’t known", var->name)); - var = var_merge(var, scope); - var->next = res; - res = var; - /* check initializer */ - if (initr->type == INITR) - semantics_initr(initr, scope, var->type); + if (var->type->type == CFUNC) + { + CType_t func = var->type; + func->name = var->name; + if (!cscope_push(scope, type2sym(func), NS_ID)) + type_merge( + cscope_lookup(scope, func->name, NS_ID)->rec.type, + func); + if (initr->type == INITR) + ERROR((var->ast, "function '%s' is initialized like a variable", func->name)); + } + else + { + if (scope->lvl && !type_is_complete(var->type)) + ERROR((var->ast, "storage size of '%s' isn’t known", var->name)); + var = var_merge(var, scope); + var->next = res; + res = var; + /* check initializer */ + if (initr->type == INITR) + semantics_initr(initr, scope, var->type); + } } useful = 1; } @@ -1123,11 +1137,20 @@ ExpType semantics_exp(CNode *p, CScope_t scope) { { CSymbol_t lu = cscope_lookup(scope, p->rec.strval, NS_ID); if (!lu) ERROR((p, "'%s' undeclared", p->rec.strval)); - p->ext.var = lu->rec.var; - res.type = p->ext.var->type; - res.lval = !(res.type->type == CARR || res.type->type == CFUNC); + if (lu->kind == CVAR) + { + p->ext.var = lu->rec.var; + res.type = p->ext.var->type; + res.lval = res.type->type != CARR; + } + else + { + p->ext.type = lu->rec.type; + res.type = p->ext.type; + res.lval = res.type->type == CFUNC; + FUNC_POINTER_CONV(res.type); + } p->ext.is_const = 0; - FUNC_POINTER_CONV(res.type); } break; case INT: @@ -1410,13 +1433,12 @@ CVar_t semantics_comp(CNode *p, CScope_t scope) { return res; } -CVar_t semantics_func(CNode *p, CScope_t scope) { +CType_t semantics_func(CNode *p, CScope_t scope) { CHECK_TYPE(p, FUNC_DEF); CVar_t head = semantics_declr(p->chd->next, semantics_type_spec(p->chd, scope), scope, 0); - CType_t func = head->type, funco; - CVar_t res = cvar_create(head->name, func, p), old = NULL; + CType_t func = head->type, efunc; CType_t rt = func->rec.func.ret; if (rt->type != CVOID && !type_is_complete(rt)) @@ -1424,6 +1446,8 @@ CVar_t semantics_func(CNode *p, CScope_t scope) { scope->func = func; func->rec.func.body = p->chd->next->next; + func->name = head->name; + free(head); cscope_enter(scope); /* enter function local scope */ { /* Note: here is a dirty hack to forcibly push function definition to the global scope, while all the types specified in parameters retain in local scope. @@ -1433,22 +1457,21 @@ CVar_t semantics_func(CNode *p, CScope_t scope) { scope->top = ntop->next; scope->lvl--; - if (cscope_push(scope, var2sym(res), NS_ID)) - old = res; - if (!old) + if (!cscope_push(scope, type2sym(func), NS_ID)) { - old = cscope_lookup(scope, res->name, NS_ID)->rec.var; - funco = old->type; - if (funco->type != CFUNC) - ERROR((res->ast, "conflicting types of '%s'", res->name)); - else if (funco->rec.func.body) - ERROR((res->ast, "redefintion of function '%s'", res->name)); - else if (!is_same_type(funco, res->type)) - ERROR((res->ast, "function defintion does not match the prototype")); - type_merge(old->type, res->type); - free(res); + CSymbol_t lu = cscope_lookup(scope, func->name, NS_ID); + if (lu->kind != CTYPE) + ERROR((func->ast, "'%s' redeclared as different kind of symbol", func->name)); + efunc = lu->rec.type; + if (efunc->type != CFUNC) + ERROR((func->ast, "conflicting types of '%s'", func->name)); + else if (efunc->rec.func.body) + ERROR((func->ast, "redefintion of function '%s'", func->name)); + else if (!is_same_type(efunc, func)) + ERROR((func->ast, "function defintion does not match the prototype")); + type_merge(efunc, func); + free(func); } - free(head); scope->top = ntop; scope->lvl++; @@ -1463,17 +1486,16 @@ CVar_t semantics_func(CNode *p, CScope_t scope) { func->rec.func.local = semantics_comp(p->chd->next->next, scope); /* check comp */ cscope_exit(scope); /* exit from local scope */ - return old; + return func; } -CVar_t make_builtin_func(const char *name, CType_t rt) { +CType_t make_builtin_func(const char *name, CType_t rt) { CType_t func = ctype_create(name, CFUNC, NULL); - CVar_t res = cvar_create(name, func, NULL); func->rec.func.params = NULL; func->rec.func.body = NULL; func->rec.func.local = NULL; func->rec.func.ret = rt; - return res; + return func; } void semantics_check(CNode *p) { @@ -1492,9 +1514,9 @@ void semantics_check(CNode *p) { cscope_push(scope, type2sym(basic_type_int), NS_TAG); cscope_push(scope, type2sym(basic_type_char), NS_TAG); cscope_push(scope, type2sym(basic_type_void), NS_TAG); - cscope_push(scope, var2sym(builtin_printf), NS_ID); - cscope_push(scope, var2sym(builtin_scanf), NS_ID); - cscope_push(scope, var2sym(builtin_malloc), NS_ID); + cscope_push(scope, type2sym(builtin_printf), NS_ID); + cscope_push(scope, type2sym(builtin_scanf), NS_ID); + cscope_push(scope, type2sym(builtin_malloc), NS_ID); /* check all definitions and declarations */ for (p = p->chd; p; p = p->next) { -- cgit v1.2.3-70-g09d2