ack/lang/m2/comp/declar.g
1986-04-06 17:42:56 +00:00

471 lines
8.6 KiB
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/* D E C L A R A T I O N S */
{
static char *RcsId = "$Header$";
#include <em_arith.h>
#include <em_label.h>
#include <assert.h>
#include "idf.h"
#include "LLlex.h"
#include "def.h"
#include "type.h"
#include "scope.h"
#include "node.h"
#include "misc.h"
}
ProcedureDeclaration
{
struct def *df;
} :
ProcedureHeading(&df, D_PROCEDURE)
';' block IDENT
{ match_id(dot.TOK_IDF, df->df_idf);
df->prc_scope = CurrentScope->sc_scope;
close_scope();
}
;
ProcedureHeading(struct def **pdf; int type;)
{
struct type *tp;
struct type *tp1 = 0;
struct paramlist *params = 0;
register struct def *df;
} :
PROCEDURE IDENT
{ assert(type & (D_PROCEDURE | D_PROCHEAD));
if (type == D_PROCHEAD) {
df = define(dot.TOK_IDF, CurrentScope, type);
}
else {
df = lookup(dot.TOK_IDF,
CurrentScope->sc_scope);
if (df && df->df_kind == D_PROCHEAD) {
df->df_kind = type;
tp1 = df->df_type;
}
else {
df = define(dot.TOK_IDF,
CurrentScope, type);
}
open_scope(OPENSCOPE, 0);
}
}
FormalParameters(type == D_PROCEDURE, &params, &tp)?
{
df->df_type = tp = construct_type(PROCEDURE, tp);
tp->prc_params = params;
if (tp1 && !TstTypeEquiv(tp, tp1)) {
error("inconsistent procedure declaration for \"%s\"", df->df_idf->id_text);
}
*pdf = df;
}
;
block:
declaration* [ BEGIN StatementSequence ]? END
;
declaration:
CONST [ ConstantDeclaration ';' ]*
|
TYPE [ TypeDeclaration ';' ]*
|
VAR [ VariableDeclaration ';' ]*
|
ProcedureDeclaration ';'
|
ModuleDeclaration ';'
;
FormalParameters(int doparams; struct paramlist **pr; struct type **tp;)
{
struct def *df;
register struct paramlist *pr1;
} :
'('
[
FPSection(doparams, pr)
{ pr1 = *pr; }
[
{ for (; pr1->next; pr1 = pr1->next) ; }
';' FPSection(doparams, &(pr1->next))
]*
]?
')'
{ *tp = 0; }
[ ':' qualident(D_TYPE | D_HTYPE, &df, "type", (struct node **) 0)
{ *tp = df->df_type; }
]?
;
/* In the next nonterminal, "doparams" is a flag indicating whether
the identifiers representing the parameters must be added to the
symbol table. We must not do so when reading a Definition Module,
because in this case we only read the header. The Implementation
might contain different identifiers representing the same paramters.
*/
FPSection(int doparams; struct paramlist **ppr;)
{
struct node *FPList;
struct paramlist *ParamList();
struct type *tp;
int VARp = 0;
} :
[
VAR { VARp = 1; }
]?
IdentList(&FPList) ':' FormalType(&tp)
{
if (doparams) {
EnterIdList(FPList, D_VARIABLE, VARp, tp, CurrentScope);
}
*ppr = ParamList(FPList, tp);
FreeNode(FPList);
}
;
FormalType(struct type **tp;)
{
struct def *df;
int ARRAYflag = 0;
} :
[ ARRAY OF { ARRAYflag = 1; }
]?
qualident(D_TYPE | D_HTYPE, &df, "type", (struct node **) 0)
{ if (ARRAYflag) {
*tp = construct_type(ARRAY, NULLTYPE);
(*tp)->arr_elem = df->df_type;
}
else *tp = df->df_type;
}
;
TypeDeclaration
{
struct def *df;
struct type *tp;
}:
IDENT { df = define(dot.TOK_IDF, CurrentScope, D_TYPE); }
'=' type(&tp)
{ df->df_type = tp;
if ((df->df_flags&D_EXPORTED) &&
tp->tp_fund == ENUMERATION) {
exprt_literals(tp->enm_enums,
enclosing(CurrentScope));
}
if (df->df_kind == D_HTYPE &&
tp->tp_fund != POINTER) {
error("Opaque type \"%s\" is not a pointer type", df->df_idf->id_text);
}
}
;
type(struct type **ptp;):
SimpleType(ptp)
|
ArrayType(ptp)
|
RecordType(ptp)
|
SetType(ptp)
|
PointerType(ptp)
|
ProcedureType(ptp)
;
SimpleType(struct type **ptp;)
{
struct def *df;
struct type *tp;
} :
qualident(D_TYPE | D_HTYPE, &df, "type", (struct node **) 0)
[
/* nothing */
|
SubrangeType(ptp)
/* The subrange type is given a base type by the
qualident (this is new modula-2).
*/
{
chk_basesubrange(*ptp, tp);
}
]
|
enumeration(ptp)
|
SubrangeType(ptp)
;
enumeration(struct type **ptp;)
{
struct node *EnumList;
} :
'(' IdentList(&EnumList) ')'
{
*ptp = standard_type(ENUMERATION,int_align,int_size);
EnterIdList(EnumList, D_ENUM, 0, *ptp, CurrentScope);
FreeNode(EnumList);
}
;
IdentList(struct node **p;)
{
register struct node *q;
} :
IDENT { q = MkNode(Value, NULLNODE, NULLNODE, &dot);
*p = q;
}
[
',' IDENT
{ q->next = MkNode(Value,NULLNODE,NULLNODE,&dot);
q = q->next;
}
]*
{ q->next = 0; }
;
SubrangeType(struct type **ptp;)
{
struct type *tp;
struct node *nd1 = 0, *nd2 = 0;
}:
/*
This is not exactly the rule in the new report, but see
the rule for "SimpleType".
*/
'[' ConstExpression(&nd1)
UPTO ConstExpression(&nd2)
']'
/*
Evaluate the expressions. Check that they are indeed constant.
???
Leave the basetype of the subrange in tp;
*/
{
/* For the time being: */
tp = int_type;
tp = construct_type(SUBRANGE, tp, (arith) 0);
*ptp = tp;
}
;
ArrayType(struct type **ptp;)
{
struct type *tp;
register struct type *tp2;
} :
ARRAY SimpleType(&tp)
{
*ptp = tp2 = construct_type(ARRAY, tp);
}
[
',' SimpleType(&tp)
{ tp2 = tp2->arr_elem =
construct_type(ARRAY, tp);
}
]* OF type(&tp)
{ tp2->arr_elem = tp; }
;
RecordType(struct type **ptp;)
{
struct scope scope;
}
:
RECORD
{ scope.sc_scope = uniq_scope();
scope.next = CurrentScope;
}
FieldListSequence(&scope)
{
*ptp = standard_type(RECORD, record_align, (arith) 0 /* ???? */);
(*ptp)->rec_scope = scope.sc_scope;
}
END
;
FieldListSequence(struct scope *scope;):
FieldList(scope)
[
';' FieldList(scope)
]*
;
FieldList(struct scope *scope;)
{
struct node *FldList;
struct idf *id;
struct def *df, *df1;
struct type *tp;
} :
[
IdentList(&FldList) ':' type(&tp)
{ EnterIdList(FldList, D_FIELD, 0, tp, scope);
FreeNode(FldList);
}
|
CASE
[
IDENT { id = dot.TOK_IDF; }
|
{ id = gen_anon_idf(); }
] /* Changed rule in new modula-2 */
':' qualident(D_TYPE|D_HTYPE, &df, "type", (struct node **) 0)
{ df1 = define(id, scope, D_FIELD);
df1->df_type = df->df_type;
}
OF variant(scope)
[
'|' variant(scope)
]*
[ ELSE FieldListSequence(scope)
]?
END
]?
;
variant(struct scope *scope;):
[ CaseLabelList ':' FieldListSequence(scope) ]?
/* Changed rule in new modula-2 */
;
CaseLabelList:
CaseLabels [ ',' CaseLabels ]*
;
CaseLabels
{
struct node *nd1, *nd2 = 0;
}:
ConstExpression(&nd1) [ UPTO ConstExpression(&nd2) ]?
;
SetType(struct type **ptp;)
{
struct type *tp;
} :
SET OF SimpleType(&tp)
{
*ptp = construct_type(SET, tp, (arith) 0 /* ???? */);
}
;
/* In a pointer type definition, the type pointed at does not
have to be declared yet, so be careful about identifying
type-identifiers
*/
PointerType(struct type **ptp;)
{
struct type *tp;
struct def *df;
struct def *lookfor();
} :
POINTER TO
[ %if ( (df = lookup(dot.TOK_IDF, CurrentScope->sc_scope)))
/* Either a Module or a Type, but in both cases defined
in this scope, so this is the correct identification
*/
qualident(D_TYPE|D_HTYPE, &df, "type", (struct node **) 0)
{
if (!df->df_type) {
error("type \"%s\" not declared",
df->df_idf->id_text);
tp = error_type;
}
else tp = df->df_type;
}
| %if (df = lookfor(dot.TOK_IDF, CurrentScope, 0),
df->df_kind == D_MODULE)
type(&tp)
|
IDENT
{ tp = NULLTYPE; }
]
{
*ptp = construct_type(POINTER, tp);
if (!tp) Forward(&dot, &((*ptp)->next));
}
;
ProcedureType(struct type **ptp;)
{
struct paramlist *pr = 0;
struct type *tp = 0;
} :
PROCEDURE FormalTypeList(&pr, &tp)?
{ *ptp = construct_type(PROCVAR, tp);
(*ptp)->prc_params = pr;
}
;
FormalTypeList(struct paramlist **ppr; struct type **ptp;)
{
struct def *df;
struct type *tp;
struct paramlist *p;
int VARp;
} :
'(' { *ppr = 0; }
[
[ VAR { VARp = 1; }
| { VARp = 0; }
]
FormalType(&tp)
{ *ppr = p = new_paramlist();
p->par_type = tp;
p->par_var = VARp;
}
[
','
[ VAR {VARp = 1; }
| {VARp = 0; }
]
FormalType(&tp)
{ p->next = new_paramlist();
p = p->next;
p->par_type = tp;
p->par_var = VARp;
}
]*
{ p->next = 0; }
]?
')'
[ ':' qualident(D_TYPE|D_HTYPE, &df, "type", (struct node **) 0)
{ *ptp = df->df_type; }
]?
;
ConstantDeclaration
{
struct def *df;
struct idf *id;
struct node *nd;
}:
IDENT { id = dot.TOK_IDF; }
'=' ConstExpression(&nd){ df = define(id, CurrentScope, D_CONST);
/* ???? */
}
;
VariableDeclaration
{
struct node *VarList;
struct type *tp;
struct node *nd = 0;
} :
IdentList(&VarList)
[
ConstExpression(&nd)
]?
':' type(&tp)
{ EnterIdList(VarList, D_VARIABLE, 0, tp, CurrentScope);
FreeNode(VarList);
}
;