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-rw-r--r--semantics.c293
1 files changed, 226 insertions, 67 deletions
diff --git a/semantics.c b/semantics.c
index 6255e10..e6fdced 100644
--- a/semantics.c
+++ b/semantics.c
@@ -254,7 +254,6 @@ void ctype_print(CType_t ct) {
for (fn = f->head[i]; fn; fn = fn->next)
{
fprintf(stderr, "%s", first ? (first = 0, "") : ",");
- fprintf(stderr, "%s:", fn->key);
cvar_print((CVar_t)fn->val);
}
}
@@ -419,12 +418,30 @@ CType_t semantics_type_spec(CNode *p, CScope_t scope) {
return type;
}
+int type_is_complete(CType_t type) {
+ switch(type->type)
+ {
+ case CINT: case CCHAR: case CPTR: case CARR:
+ return 1;
+ case CSTRUCT: case CUNION:
+ return type->rec.fields != NULL;
+ default: ; /* TODO: CFUNC CVOID */
+ }
+ return 1;
+}
+
CVar_t semantics_declr(CNode *, CType_t, CScope_t);
CVar_t semantics_p_decl(CNode *p, CScope_t scope) {
CHECK_TYPE(p, PLAIN_DECL);
- return semantics_declr(p->chd->next,
- semantics_type_spec(p->chd, scope),
- scope);
+ CVar_t var = semantics_declr(p->chd->next,
+ semantics_type_spec(p->chd, scope),
+ scope);
+ if (!type_is_complete(var->type))
+ {
+ sprintf(err_buff, "parameter '%s' has incomplete type", var->name);
+ ERROR(var->ast);
+ }
+ return var;
}
CType_t semantics_type_name(CNode *p, CScope_t scope) {
@@ -458,7 +475,7 @@ CVar_t semantics_params(CNode *p, CScope_t scope) {
CHECK_TYPE(p, PARAMS);
p = p->chd;
if (p->type == NOP) return NULL; /* void arguments */
- CVar_t params = semantics_p_decl(p, scope);
+ CVar_t params = semantics_p_decl(p, scope), tail = params;
cscope_push_var(scope, params);
for (p = p->next; p; p = p->next)
{
@@ -469,8 +486,8 @@ CVar_t semantics_params(CNode *p, CScope_t scope) {
sprintf(err_buff, "redefinition of parameter '%s'", var->name);
ERROR(var->ast);
}
- var->next = params;
- params = var;
+ tail->next = var;
+ tail = var;
}
return params;
}
@@ -577,9 +594,14 @@ CTable_t semantics_fields(CNode *p, CScope_t scope) {
for (; declr; declr = declr->next)
{
CVar_t var = semantics_declr(declr,
- semantics_type_spec(p->chd, scope),
- scope);
- /* TODO: conflicts report */
+ semantics_type_spec(p->chd, scope),
+ scope);
+ /* incomplete type checking */
+ if (!type_is_complete(var->type))
+ {
+ sprintf(err_buff, "field '%s' has incomplete type", var->name);
+ ERROR(var->ast);
+ }
if (!ctable_insert(ct, var->name, var, 0))
{
sprintf(err_buff, "duplicate member '%s'", var->name);
@@ -609,6 +631,11 @@ CVar_t semantics_decl(CNode *p, CScope_t scope) {
{
/* TODO: initializer checking */
CVar_t var = semantics_declr(p->chd, type, scope);
+ if (!type_is_complete(var->type))
+ {
+ sprintf(err_buff, "storage size of '%s' isn’t known", var->name);
+ ERROR(var->ast);
+ }
var = var_merge(var, scope);
var->next = res;
res = var;
@@ -624,49 +651,49 @@ CVar_t semantics_decl(CNode *p, CScope_t scope) {
return res;
}
-#define INCOMP_TYPE(ast) \
- do { \
- sprintf(err_buff, "incompatible types when assigning"); \
- ERROR(ast); \
- } while (0)
-
#define NOT_IGNORE_VOID(et, ast) \
- if (et.type->type == CVOID) \
+ if (et->type == CVOID) \
do \
{ \
sprintf(err_buff, "void value not ignored as it ought to be"); \
ERROR(ast); \
} while (0)
+#define INCOMP_TYPE(ast) \
+ do { \
+ sprintf(err_buff, "incompatible types when assigning"); \
+ ERROR(ast); \
+ } while (0)
-ExpType exp_check_aseq(ExpType lhs, ExpType rhs, CNode *ast) {
+void exp_check_aseq_(CType_t lhs, CType_t rhs, CNode *ast) {
NOT_IGNORE_VOID(lhs, ast);
NOT_IGNORE_VOID(rhs, ast);
- switch (lhs.type->type)
+ switch (lhs->type)
{
case CSTRUCT: case CUNION:
- if (!is_same_type(lhs.type, rhs.type, 0))
+ if (!is_same_type(lhs, rhs, 0))
INCOMP_TYPE(ast);
break;
case CARR: case CFUNC: /* constant */
INCOMP_TYPE(ast);
break;
case CINT: case CCHAR:
- switch (rhs.type->type)
+ switch (rhs->type)
{
- case CINT: case CCHAR: ; break; /* ok */
- case CPTR:
- sprintf(err_buff, "assignment makes integer from pointer without a cast");
- WARNING(ast);
- break;
+ case CINT: case CCHAR:
+ ; break; /* ok */
+ case CPTR: case CARR:
+ sprintf(err_buff, "assignment makes integer from pointer without a cast");
+ WARNING(ast);
+ break;
default: INCOMP_TYPE(ast);
}
break;
case CPTR:
- switch (rhs.type->type)
+ switch (rhs->type)
{
- case CPTR:
- if (!is_same_type(lhs.type->rec.ref, rhs.type->rec.ref, 1))
+ case CPTR: case CARR:
+ if (!is_same_type(lhs->rec.ref, rhs->rec.ref, 1))
{
sprintf(err_buff, "assignment from incompatible pointer type");
WARNING(ast);
@@ -681,6 +708,11 @@ ExpType exp_check_aseq(ExpType lhs, ExpType rhs, CNode *ast) {
break;
default: assert(0);
}
+}
+
+
+ExpType exp_check_aseq(ExpType lhs, ExpType rhs, CNode *ast) {
+ exp_check_aseq_(lhs.type, rhs.type, ast);
return lhs;
}
@@ -692,8 +724,8 @@ ExpType exp_check_arith(ExpType op1, ExpType op2, CNode *ast) {
int t1 = op1.type->type,
t2 = op2.type->type;
ExpType res;
- NOT_IGNORE_VOID(op1, ast);
- NOT_IGNORE_VOID(op2, ast);
+ NOT_IGNORE_VOID(op1.type, ast);
+ NOT_IGNORE_VOID(op2.type, ast);
res.lval = 0;
res.type = basic_type_int;
if (!(IS_ARITH(t1) && IS_ARITH(t2)))
@@ -708,8 +740,8 @@ ExpType exp_check_bitwise(ExpType op1, ExpType op2, CNode *ast) {
int t1 = op1.type->type,
t2 = op2.type->type;
ExpType res;
- NOT_IGNORE_VOID(op1, ast);
- NOT_IGNORE_VOID(op2, ast);
+ NOT_IGNORE_VOID(op1.type, ast);
+ NOT_IGNORE_VOID(op2.type, ast);
res.lval = 0;
res.type = basic_type_int;
if (!(IS_INT(t1) && IS_INT(t2)))
@@ -723,8 +755,8 @@ ExpType exp_check_bitwise(ExpType op1, ExpType op2, CNode *ast) {
ExpType exp_check_add(ExpType op1, ExpType op2, CNode *ast, int sub) {
int t1 = op1.type->type,
t2 = op2.type->type;
- NOT_IGNORE_VOID(op1, ast);
- NOT_IGNORE_VOID(op2, ast);
+ NOT_IGNORE_VOID(op1.type, ast);
+ NOT_IGNORE_VOID(op2.type, ast);
if (!sub && t2 == CPTR)
{
/* place the pointer type in the first place */
@@ -779,7 +811,11 @@ ExpType exp_check_deref(ExpType op1, CNode *ast) {
ERROR(ast);
}
op1.lval = 1; /* deref changes exp to lval */
- op1.type = op1.type->rec.ref;
+ if (!type_is_complete(op1.type = op1.type->rec.ref))
+ {
+ sprintf(err_buff, "dereferencing pointer to incomplete type");
+ ERROR(ast);
+ }
return op1;
}
@@ -796,14 +832,34 @@ ExpType exp_check_ref(ExpType op1, CNode *ast) {
return res;
}
+ExpType exp_check_sizeof(ExpType op1, CNode *ast) {
+ op1.lval = 0;
+ op1.type = basic_type_int;
+ return op1;
+}
+
+ExpType exp_check_preinc(ExpType op1, CNode *ast) {
+ if (!IS_SCALAR(op1.type->type))
+ {
+ sprintf(err_buff, "wrong type argument to increment/decrement");
+ ERROR(ast);
+ }
+ if (!op1.lval)
+ {
+ sprintf(err_buff, "lvalue required as increment/decrement operand");
+ ERROR(ast);
+ }
+ return op1;
+}
+
ExpType semantics_exp(CNode *, CScope_t);
ExpType exp_check_logical(ExpType op1, ExpType op2, CNode *ast) {
int t1 = op1.type->type,
t2 = op2.type->type;
ExpType res;
- NOT_IGNORE_VOID(op1, ast);
- NOT_IGNORE_VOID(op2, ast);
+ NOT_IGNORE_VOID(op1.type, ast);
+ NOT_IGNORE_VOID(op2.type, ast);
res.lval = 0;
res.type = basic_type_int;
if (!(IS_SCALAR(t1) && IS_SCALAR(t2)))
@@ -815,8 +871,8 @@ ExpType exp_check_logical(ExpType op1, ExpType op2, CNode *ast) {
}
ExpType exp_check_ass(ExpType lhs, ExpType rhs, CNode *p) {
- NOT_IGNORE_VOID(lhs, p);
- NOT_IGNORE_VOID(rhs, p);
+ NOT_IGNORE_VOID(lhs.type, p);
+ NOT_IGNORE_VOID(rhs.type, p);
if (!lhs.lval)
{
sprintf(err_buff, "lvalue required as left operand of assignment");
@@ -845,8 +901,8 @@ ExpType exp_check_equality(ExpType op1, ExpType op2, CNode *ast) {
int t1 = op1.type->type,
t2 = op2.type->type;
ExpType res;
- NOT_IGNORE_VOID(op1, ast);
- NOT_IGNORE_VOID(op2, ast);
+ NOT_IGNORE_VOID(op1.type, ast);
+ NOT_IGNORE_VOID(op2.type, ast);
res.lval = 0;
res.type = basic_type_int;
if (IS_ARITH(t1) && IS_ARITH(t2))
@@ -872,6 +928,103 @@ ExpType exp_check_equality(ExpType op1, ExpType op2, CNode *ast) {
return res;
}
+ExpType exp_check_postfix(CNode *p, CScope_t scope) {
+ CNode *post = p->chd->next;
+ ExpType op1 = semantics_exp(p->chd, scope), op2;
+ int t1 = op1.type->type, t2;
+ switch (post->rec.subtype)
+ {
+ case POSTFIX_ARR:
+ if (!(t1 == CARR || t1 == CPTR))
+ {
+ sprintf(err_buff, "subscripted value is neither array nor pointer");
+ ERROR(p);
+ }
+ op2 = semantics_exp(post, scope);
+ t2 = op2.type->type;
+ if (!IS_INT(t2))
+ {
+ sprintf(err_buff, "array subscript is not an integer");
+ ERROR(p);
+ }
+ op1.type = op1.type->rec.arr.elem;
+ op1.lval = 1;
+ break;
+ case POSTFIX_CALL:
+ if (t1 != CFUNC)
+ {
+ sprintf(err_buff, "called object is not a function");
+ ERROR(p);
+ }
+ {
+ CNode *arg = post->chd->chd;
+ CType_t func = p->chd->ext.type;
+ CVar_t param = func->rec.func.params;
+ for (; arg && param;
+ arg = arg->next, param = param->next)
+ {
+ semantics_exp(arg, scope);
+ exp_check_aseq_(param->type, arg->ext.type, arg);
+ }
+ if (arg || param)
+ {
+ sprintf(err_buff, "too many/few arguments to the function");
+ ERROR(p);
+ }
+ op1.type = func->rec.func.ret;
+ op1.lval = 0;
+ break;
+ }
+ case POSTFIX_DOT:
+ if (!(t1 == CSTRUCT || t1 == CUNION))
+ {
+ sprintf(err_buff, "request for the member in something not a structure or union");
+ ERROR(p);
+ }
+ {
+ CVar_t fv = ctable_lookup(op1.type->rec.fields, post->chd->rec.strval);
+ if (!fv)
+ {
+ sprintf(err_buff, "struct/union has no member named '%s'", post->chd->rec.strval);
+ ERROR(p);
+ }
+ op1.type = fv->type;
+ op1.lval = 1;
+ }
+ break;
+ case POSTFIX_PTR:
+ if (t1 != CPTR)
+ {
+ sprintf(err_buff, "invalid type argument of '->'");
+ ERROR(p);
+ }
+ {
+ CType_t tref = op1.type->rec.ref;
+ if (!(tref->type == CSTRUCT || tref->type == CUNION))
+ {
+ sprintf(err_buff, "request for the member in something not a structure or union");
+ ERROR(p);
+ }
+ if (!tref->rec.fields)
+ {
+ sprintf(err_buff, "dereferencing pointer to incomplete type");
+ ERROR(p);
+ }
+ CVar_t fv = ctable_lookup(tref->rec.fields, post->chd->rec.strval);
+ if (!fv)
+ {
+ sprintf(err_buff, "struct/union has no member named '%s'", post->chd->rec.strval);
+ ERROR(p);
+ }
+ op1.type = fv->type;
+ op1.lval = 1;
+ }
+ break;
+ default: assert(0);
+ }
+ return op1;
+}
+
ExpType semantics_exp(CNode *p, CScope_t scope) {
ExpType res;
switch (p->type)
@@ -883,7 +1036,7 @@ ExpType semantics_exp(CNode *p, CScope_t scope) {
ERROR(p);
}
res.type = p->ext.var->type;
- res.lval = 1;
+ res.lval = !(res.type->type == CARR || res.type->type == CFUNC);
break;
case INT:
res.type = basic_type_int;
@@ -903,7 +1056,7 @@ ExpType semantics_exp(CNode *p, CScope_t scope) {
{
ExpType op1;
ExpType op2;
- if (p->rec.subtype != EXP_CAST)
+ if (!(p->rec.subtype == EXP_CAST || p->rec.subtype == EXP_POSTFIX))
{
op1 = semantics_exp(p->chd, scope);
if (p->chd->next)
@@ -987,7 +1140,15 @@ ExpType semantics_exp(CNode *p, CScope_t scope) {
case '!':
res = exp_check_scalar(op1, p);
break;
-
+ case OPT_INC: case OPT_DEC:
+ res = exp_check_preinc(op1, p);
+ break;
+ case KW_SIZEOF:
+ res = exp_check_sizeof(op1, p);
+ break;
+ case EXP_POSTFIX:
+ res = exp_check_postfix(p, scope);
+ break;
default: assert(0);
}
}
@@ -1079,7 +1240,7 @@ CVar_t semantics_func(CNode *p, CScope_t scope) {
CHECK_TYPE(p, FUNC_DEF);
CNode *chd = p->chd->next;
CType_t func = ctype_create(chd->rec.strval, CFUNC, p), funco;
- CVar_t res, old;
+ CVar_t res = cvar_create(func->name, func, p), old;
chd = chd->next;
func->rec.func.ret = semantics_type_spec(p->chd, scope); /* check return type */
@@ -1088,33 +1249,31 @@ CVar_t semantics_func(CNode *p, CScope_t scope) {
func->rec.func.local = semantics_comp(chd->next, scope); /* check comp */
func->rec.func.body = chd->next;
cscope_exit(scope); /* exit from local scope */
- res = cvar_create(func->name, func, p);
-
if (cscope_push_var(scope, res))
- return res;
+ old = res;
else
{
old = cscope_lookup_var(scope, res->name);
funco = old->type;
+ if (funco->type != CFUNC)
+ {
+ sprintf(err_buff, "conflicting types of '%s'", res->name);
+ ERROR(res->ast);
+ }
+ else if (funco->rec.func.body)
+ {
+ sprintf(err_buff, "redefintion of function '%s'", res->name);
+ ERROR(res->ast);
+ }
+ else if (!is_same_type(funco, res->type, 0))
+ {
+ sprintf(err_buff, "function defintion does not match the prototype");
+ ERROR(res->ast);
+ }
+ funco->rec.func.local = res->type->rec.func.local;
+ funco->rec.func.body = res->type->rec.func.body;
+ free(res);
}
- if (funco->type != CFUNC)
- {
- sprintf(err_buff, "conflicting types of '%s'", res->name);
- ERROR(res->ast);
- }
- else if (funco->rec.func.body)
- {
- sprintf(err_buff, "redefintion of function '%s'", res->name);
- ERROR(res->ast);
- }
- else if (!is_same_type(funco, res->type, 0))
- {
- sprintf(err_buff, "function defintion does not match the prototype");
- ERROR(res->ast);
- }
- funco->rec.func.local = res->type->rec.func.local;
- funco->rec.func.body = res->type->rec.func.body;
- free(res);
return old;
}