ack/lang/m2/comp/declar.g
1987-07-13 10:30:37 +00:00

514 lines
9.3 KiB
Plaintext

/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*
* Author: Ceriel J.H. Jacobs
*/
/* D E C L A R A T I O N S */
/* $Header$ */
{
#include "debug.h"
#include <em_arith.h>
#include <em_label.h>
#include <alloc.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"
#include "main.h"
#include "chk_expr.h"
#include "warning.h"
int proclevel = 0; /* nesting level of procedures */
int return_occurred; /* set if a return occurs in a block */
#define needs_static_link() (proclevel > 1)
}
/* inline in declaration: need space
ProcedureDeclaration
{
struct def *df;
} :
{ ++proclevel; }
ProcedureHeading(&df, D_PROCEDURE)
';' block(&(df->prc_body))
IDENT
{ EndProc(df, dot.TOK_IDF);
--proclevel;
}
;
*/
ProcedureHeading(struct def **pdf; int type;)
{
struct type *tp = 0;
arith parmaddr = needs_static_link() ? pointer_size : 0;
struct paramlist *pr = 0;
} :
PROCEDURE IDENT
{ *pdf = DeclProc(type, dot.TOK_IDF); }
[
'('
[
FPSection(&pr, &parmaddr)
[
';' FPSection(&pr, &parmaddr)
]*
]?
')'
[ ':' qualtype(&tp)
]?
]?
{ CheckWithDef(*pdf, proc_type(tp, pr, parmaddr));
if (tp && IsConstructed(tp)) {
warning(W_STRICT, "procedure \"%s\" has a constructed result type",
(*pdf)->df_idf->id_text);
}
}
;
block(struct node **pnd;) :
[ %persistent
declaration
]*
{ return_occurred = 0; *pnd = 0; }
[ %persistent
BEGIN
StatementSequence(pnd)
]?
END
;
declaration
{
struct def *df;
} :
CONST [ ConstantDeclaration ';' ]*
|
TYPE [ TypeDeclaration ';' ]*
|
VAR [ VariableDeclaration ';' ]*
|
{ ++proclevel; }
ProcedureHeading(&df, D_PROCEDURE)
';'
block(&(df->prc_body))
IDENT
{ EndProc(df, dot.TOK_IDF);
--proclevel;
}
';'
|
ModuleDeclaration ';'
;
/* inline in procedureheading: need space
FormalParameters(struct paramlist **ppr; arith *parmaddr; struct type **ptp;):
'('
[
FPSection(ppr, parmaddr)
[
';' FPSection(ppr, parmaddr)
]*
]?
')'
[ ':' qualtype(ptp)
]?
;
*/
FPSection(struct paramlist **ppr; arith *parmaddr;)
{
struct node *FPList;
struct type *tp;
int VARp;
} :
var(&VARp) IdentList(&FPList) ':' FormalType(&tp)
{ EnterParamList(ppr, FPList, tp, VARp, parmaddr); }
;
FormalType(struct type **ptp;)
{
extern arith ArrayElSize();
} :
ARRAY OF qualtype(ptp)
{ register struct type *tp = construct_type(T_ARRAY, NULLTYPE);
tp->arr_elem = *ptp;
*ptp = tp;
tp->arr_elsize = ArrayElSize(tp->arr_elem);
tp->tp_align = tp->arr_elem->tp_align;
}
|
qualtype(ptp)
;
TypeDeclaration
{
struct def *df;
struct type *tp;
register struct node *nd;
}:
IDENT { df = define(dot.TOK_IDF, CurrentScope, D_TYPE);
nd = MkLeaf(Name, &dot);
}
'=' type(&tp)
{ DeclareType(nd, df, tp);
free_node(nd);
}
;
type(register struct type **ptp;):
%default SimpleType(ptp)
|
ArrayType(ptp)
|
RecordType(ptp)
|
SetType(ptp)
|
PointerType(ptp)
|
ProcedureType(ptp)
;
SimpleType(register struct type **ptp;)
{
struct type *tp;
} :
qualtype(ptp)
[
/* nothing */
|
SubrangeType(&tp)
/* The subrange type is given a base type by the
qualident (this is new modula-2).
*/
{ chk_basesubrange(tp, *ptp); *ptp = tp; }
]
|
enumeration(ptp)
|
SubrangeType(ptp)
;
enumeration(struct type **ptp;)
{
struct node *EnumList;
} :
'(' IdentList(&EnumList) ')'
{ *ptp = enum_type(EnumList); }
;
IdentList(struct node **p;)
{
register struct node *q;
} :
IDENT { *p = q = MkLeaf(Value, &dot); }
[ %persistent
',' IDENT
{ q->next = MkLeaf(Value, &dot);
q = q->next;
}
]*
{ q->next = 0; }
;
SubrangeType(struct type **ptp;)
{
struct node *nd1, *nd2;
}:
/*
This is not exactly the rule in the new report, but see
the rule for "SimpleType".
*/
'[' ConstExpression(&nd1)
UPTO ConstExpression(&nd2)
']'
{ *ptp = subr_type(nd1, nd2);
free_node(nd1);
free_node(nd2);
}
;
ArrayType(struct type **ptp;)
{
struct type *tp;
register struct type *tp2;
} :
ARRAY SimpleType(&tp)
{ *ptp = tp2 = construct_type(T_ARRAY, tp); }
[
',' SimpleType(&tp)
{ tp2->arr_elem = construct_type(T_ARRAY, tp);
tp2 = tp2->arr_elem;
}
]* OF type(&tp)
{ tp2->arr_elem = tp;
ArraySizes(*ptp);
}
;
RecordType(struct type **ptp;)
{
register struct scope *scope;
arith size = 0;
int xalign = struct_align;
}
:
RECORD
{ scope = open_and_close_scope(OPENSCOPE); }
FieldListSequence(scope, &size, &xalign)
{ if (size == 0) {
warning(W_ORDINARY, "empty record declaration");
size = 1;
}
*ptp = standard_type(T_RECORD, xalign, size);
(*ptp)->rec_scope = scope;
}
END
;
FieldListSequence(struct scope *scope; arith *cnt; int *palign;):
FieldList(scope, cnt, palign)
[
';' FieldList(scope, cnt, palign)
]*
;
FieldList(struct scope *scope; arith *cnt; int *palign;)
{
struct node *FldList;
struct type *tp;
struct node *nd;
register struct def *df;
arith tcnt, max;
} :
[
IdentList(&FldList) ':' type(&tp)
{
*palign = lcm(*palign, tp->tp_align);
EnterFieldList(FldList, tp, scope, cnt);
}
|
CASE
/* Also accept old fashioned Modula-2 syntax, but give a warning.
Sorry for the complicated code.
*/
[ qualident(&nd)
[ ':' qualtype(&tp)
/* This is correct, in both kinds of Modula-2, if
the first qualident is a single identifier.
*/
{ if (nd->nd_class != Name) {
error("illegal variant tag");
}
else {
df = define(nd->nd_IDF, scope, D_FIELD);
*palign = lcm(*palign, tp->tp_align);
if (!(tp->tp_fund & T_DISCRETE)) {
error("illegal type in variant");
}
df->df_type = tp;
df->fld_off = align(*cnt, tp->tp_align);
*cnt = df->fld_off + tp->tp_size;
df->df_flags |= D_QEXPORTED;
}
FreeNode(nd);
}
| /* Old fashioned! the first qualident now represents
the type
*/
{ warning(W_OLDFASHIONED,
"old fashioned Modula-2 syntax; ':' missing");
tp = qualified_type(nd);
}
]
| ':' qualtype(&tp)
/* Aha, third edition. Well done! */
]
{ tcnt = *cnt; }
OF variant(scope, &tcnt, tp, palign)
{ max = tcnt; tcnt = *cnt; }
[
'|' variant(scope, &tcnt, tp, palign)
{ if (tcnt > max) max = tcnt; tcnt = *cnt; }
]*
[ ELSE FieldListSequence(scope, &tcnt, palign)
{ if (tcnt > max) max = tcnt; }
]?
END
{ *cnt = max; }
]?
;
variant(struct scope *scope; arith *cnt; struct type *tp; int *palign;)
{
struct node *nd;
} :
[
CaseLabelList(&tp, &nd)
{ /* Ignore the cases for the time being.
Maybe a checking version will be supplied
later ???
*/
FreeNode(nd);
}
':' FieldListSequence(scope, cnt, palign)
]?
/* Changed rule in new modula-2 */
;
CaseLabelList(struct type **ptp; struct node **pnd;):
CaseLabels(ptp, pnd)
[
{ *pnd = MkNode(Link, *pnd, NULLNODE, &dot); }
',' CaseLabels(ptp, &((*pnd)->nd_right))
{ pnd = &((*pnd)->nd_right); }
]*
;
CaseLabels(struct type **ptp; register struct node **pnd;)
{
register struct node *nd;
}:
ConstExpression(pnd)
{ nd = *pnd; }
[
UPTO { *pnd = MkNode(Link,nd,NULLNODE,&dot); }
ConstExpression(&(*pnd)->nd_right)
{ if (!TstCompat(nd->nd_type,
(*pnd)->nd_right->nd_type)) {
node_error((*pnd)->nd_right,
"type incompatibility in case label");
nd->nd_type = error_type;
}
}
]?
{ if (*ptp != 0 && !TstCompat(*ptp, nd->nd_type)) {
node_error(nd,
"type incompatibility in case label");
}
*ptp = nd->nd_type;
}
;
SetType(struct type **ptp;) :
SET OF SimpleType(ptp)
{ *ptp = set_type(*ptp); }
;
/* In a pointer type definition, the type pointed at does not
have to be declared yet, so be careful about identifying
type-identifiers
*/
PointerType(register struct type **ptp;) :
POINTER TO
[ %if (type_or_forward(ptp))
type(&((*ptp)->next))
|
IDENT
]
;
qualtype(struct type **ptp;)
{
struct node *nd;
} :
qualident(&nd)
{ *ptp = qualified_type(nd); }
;
ProcedureType(struct type **ptp;) :
PROCEDURE
[
FormalTypeList(ptp)
|
{ *ptp = proc_type((struct type *) 0,
(struct paramlist *) 0,
(arith) 0);
}
]
;
FormalTypeList(struct type **ptp;)
{
struct paramlist *pr = 0;
arith parmaddr = 0;
} :
'('
[
VarFormalType(&pr, &parmaddr)
[
',' VarFormalType(&pr, &parmaddr)
]*
]?
')'
[ ':' qualtype(ptp)
]?
{ *ptp = proc_type(*ptp, pr, parmaddr); }
;
VarFormalType(struct paramlist **ppr; arith *parmaddr;)
{
struct type *tp;
int isvar;
} :
var(&isvar)
FormalType(&tp)
{ EnterParamList(ppr,NULLNODE,tp,isvar,parmaddr); }
;
var(int *VARp;) :
[
VAR { *VARp = D_VARPAR; }
|
/* empty */ { *VARp = D_VALPAR; }
]
;
ConstantDeclaration
{
struct idf *id;
struct node *nd;
}:
IDENT { id = dot.TOK_IDF; }
'=' ConstExpression(&nd)
{ define(id,CurrentScope,D_CONST)->con_const = nd; }
;
VariableDeclaration
{
struct node *VarList;
register struct node *nd;
struct type *tp;
} :
IdentAddr(&VarList)
{ nd = VarList; }
[ %persistent
',' IdentAddr(&(nd->nd_right))
{ nd = nd->nd_right; }
]*
':' type(&tp)
{ EnterVarList(VarList, tp, proclevel > 0); }
;
IdentAddr(register struct node **pnd;) :
IDENT { *pnd = MkLeaf(Name, &dot); }
[ '['
ConstExpression(&((*pnd)->nd_left))
']'
]?
;