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authorTeddy <[email protected]>2014-04-04 22:07:11 +0800
committerTeddy <[email protected]>2014-04-04 22:07:11 +0800
commitdcab32187ccd3d7e31e2e01e4c1b313fdad52f99 (patch)
treef6318110fc79ef3f06aa758877c87f0d0bb5b62b
parent2f2b0feb722f30211d261b5653f936227f10f91a (diff)
...
-rw-r--r--semantics.c82
-rw-r--r--semantics.h1
2 files changed, 58 insertions, 25 deletions
diff --git a/semantics.c b/semantics.c
index 3f481a9..a86462c 100644
--- a/semantics.c
+++ b/semantics.c
@@ -292,25 +292,32 @@ void ctype_print(CType_t ct) {
}
}
-static CType_t type_merge(CType_t new, CScope_t scope) {
- CType_t old;
- if (cscope_push_type(scope, new))
+static CType_t struct_type_merge(CType_t new, CScope_t scope) {
+ /* Note: we shall try to lookup first instead of pushing !! */
+ CType_t old = cscope_lookup_type(scope, new->name);
+ if (!old) /* create it if it does not exist */
+ {
+ cscope_push_type(scope, new);
return new;
- else
- old = cscope_lookup_type(scope, new->name);
- if (old->type != new->type)
+ } /* otherwise we have it */
+ if (old->type != new->type) /* not a struct or union */
{
sprintf(err_buff, "conflicting types of '%s'", new->name);
ERROR(new->ast->loc.row, new->ast->loc.col);
}
- if (!new->rec.fields)
+ /* otherwise it is a struct or union */
+ if (!new->rec.fields) /* use the old definition */
return old;
- if (old->rec.fields)
+ /* otherwise there's a completion definition */
+ if (cscope_push_type(scope, new)) /* try to push the defintion */
+ return new;
+ /* conflict appear */
+ if (old->rec.fields) /* if the old one is complete */
{
sprintf(err_buff, "redefinition of '%s'", new->name);
ERROR(new->ast->loc.row, new->ast->loc.col);
}
- /* complete the type */
+ /* otherwise incomplete, thus complete the type */
old->next = new->next;
old->rec.fields = new->rec.fields;
old->ast = new->ast;
@@ -343,7 +350,8 @@ int is_same_type(CType_t typea, CType_t typeb) {
return 0;
if (pa || pb)
return 0; /* different number of parameters */
- break;
+ return is_same_type(typea->rec.func.ret,
+ typeb->rec.func.ret);
}
case CINT: case CCHAR: case CVOID:
;
@@ -389,7 +397,7 @@ CType_t semantics_type_spec(CNode *p, CScope_t scope) {
type->rec.fields = semantics_fields(fields, scope);
if (id->type != NOP)
- type = type_merge(type, scope);
+ type = struct_type_merge(type, scope);
}
break;
default: assert(0);
@@ -474,6 +482,7 @@ CVar_t semantics_declr(CNode *p, CType_t type_spec, CScope_t scope) {
/* incomplete type */
type->rec.func.local = NULL;
type->rec.func.ret = p_declr->type;
+ type->rec.func.body = NULL; /* not a definition */
name = p_declr->name;
ast = p_declr->ast;
free(p_declr);
@@ -537,15 +546,12 @@ CVar_t semantics_decl(CNode *p, CScope_t scope) {
CNode *init = p->chd->next;
CType_t type = semantics_type_spec(p->chd, scope);
CVar_t res = NULL;
- switch (type->type)
+ int useful = 0;
+ if ((type->type == CSTRUCT || type->type == CUNION) &&
+ (*type->name) != '\0')
{
- case CSTRUCT:
- case CUNION:
- cscope_push_type(scope, type); break;
- case CINT:
- case CCHAR:
- case CVOID: break;
- default: assert(0);
+ cscope_push_type(scope, type);
+ useful = 1;
}
if (init->chd->type != NOP)
{
@@ -558,8 +564,9 @@ CVar_t semantics_decl(CNode *p, CScope_t scope) {
var->next = res;
res = var;
}
+ useful = 1;
}
- else
+ if (!useful)
{
/* TODO: useless typename warning */
sprintf(err_buff, "useless declaration");
@@ -647,19 +654,44 @@ CVar_t semantics_comp(CNode *p, CScope_t scope) {
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);
- CVar_t res;
+ CType_t func = ctype_create(chd->rec.strval, CFUNC, p), funco;
+ CVar_t res, old;
chd = chd->next;
func->rec.func.ret = semantics_type_spec(p->chd, scope); /* check return type */
cscope_enter(scope); /* enter into function local scope */
func->rec.func.params = semantics_params(chd, scope); /* check params */
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))
- puts("fuck func name");
- return res;
+
+ if (cscope_push_var(scope, res))
+ return 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->loc.row, res->ast->loc.col);
+ }
+ else if (funco->rec.func.body)
+ {
+ sprintf(err_buff, "redefintion of function '%s'", res->name);
+ ERROR(res->ast->loc.row, res->ast->loc.col);
+ }
+ else if (!is_same_type(funco, res->type))
+ {
+ sprintf(err_buff, "function defintion does not match the prototype");
+ ERROR(res->ast->loc.row, res->ast->loc.col);
+ }
+ funco->rec.func.local = res->type->rec.func.local;
+ funco->rec.func.body = res->type->rec.func.body;
+ free(res);
+ return old;
}
void semantics_check_(CNode *p, CScope_t scope) {
diff --git a/semantics.h b/semantics.h
index dfbf7b7..b770156 100644
--- a/semantics.h
+++ b/semantics.h
@@ -43,6 +43,7 @@ typedef struct CType {
CVar *params;
CVar *local;
struct CType *ret;
+ CNode *body;
} func; /* for a function */
} rec;
int size; /* memory footprint */