379 lines
7.5 KiB
C
379 lines
7.5 KiB
C
/* D E S I G N A T O R E V A L U A T I O N */
|
|
|
|
#ifndef NORCSID
|
|
static char *RcsId = "$Header$";
|
|
#endif
|
|
|
|
/* Code generation for designators.
|
|
This file contains some routines that generate code common to address
|
|
as well as value computations, and leave a description in a "desig"
|
|
structure. It also contains routines to load an address, load a value
|
|
or perform a store.
|
|
*/
|
|
|
|
#include "debug.h"
|
|
|
|
#include <em_arith.h>
|
|
#include <em_label.h>
|
|
#include <em_code.h>
|
|
#include <assert.h>
|
|
|
|
#include "type.h"
|
|
#include "def.h"
|
|
#include "scope.h"
|
|
#include "desig.h"
|
|
#include "LLlex.h"
|
|
#include "node.h"
|
|
|
|
extern int proclevel;
|
|
struct desig InitDesig = {DSG_INIT, 0, 0};
|
|
|
|
CodeValue(ds, size)
|
|
register struct desig *ds;
|
|
arith size;
|
|
{
|
|
/* Generate code to load the value of the designator described
|
|
in "ds"
|
|
*/
|
|
|
|
switch(ds->dsg_kind) {
|
|
case DSG_LOADED:
|
|
break;
|
|
|
|
case DSG_FIXED:
|
|
if (size == word_size) {
|
|
if (ds->dsg_name) {
|
|
C_loe_dnam(ds->dsg_name, ds->dsg_offset);
|
|
}
|
|
else C_lol(ds->dsg_offset);
|
|
break;
|
|
}
|
|
|
|
if (size == dword_size) {
|
|
if (ds->dsg_name) {
|
|
C_lde_dnam(ds->dsg_name, ds->dsg_offset);
|
|
}
|
|
else C_ldl(ds->dsg_offset);
|
|
break;
|
|
}
|
|
/* Fall through */
|
|
case DSG_PLOADED:
|
|
case DSG_PFIXED:
|
|
CodeAddress(ds);
|
|
C_loi(size);
|
|
break;
|
|
|
|
case DSG_INDEXED:
|
|
C_lar(word_size);
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeValue)");
|
|
}
|
|
|
|
ds->dsg_kind = DSG_LOADED;
|
|
}
|
|
|
|
CodeStore(ds, size)
|
|
register struct desig *ds;
|
|
arith size;
|
|
{
|
|
/* Generate code to store the value on the stack in the designator
|
|
described in "ds"
|
|
*/
|
|
|
|
switch(ds->dsg_kind) {
|
|
case DSG_FIXED:
|
|
if (size == word_size) {
|
|
if (ds->dsg_name) {
|
|
C_ste_dnam(ds->dsg_name, ds->dsg_offset);
|
|
}
|
|
else C_stl(ds->dsg_offset);
|
|
break;
|
|
}
|
|
|
|
if (size == dword_size) {
|
|
if (ds->dsg_name) {
|
|
C_sde_dnam(ds->dsg_name, ds->dsg_offset);
|
|
}
|
|
else C_sdl(ds->dsg_offset);
|
|
break;
|
|
}
|
|
/* Fall through */
|
|
case DSG_PLOADED:
|
|
case DSG_PFIXED:
|
|
CodeAddress(ds);
|
|
C_sti(size);
|
|
break;
|
|
|
|
case DSG_INDEXED:
|
|
C_sar(word_size);
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeStore)");
|
|
}
|
|
|
|
ds->dsg_kind = DSG_INIT;
|
|
}
|
|
|
|
CodeAddress(ds)
|
|
register struct desig *ds;
|
|
{
|
|
/* Generate code to load the address of the designator described
|
|
in "ds"
|
|
*/
|
|
|
|
switch(ds->dsg_kind) {
|
|
case DSG_PLOADED:
|
|
if (ds->dsg_offset) {
|
|
C_adp(ds->dsg_offset);
|
|
}
|
|
break;
|
|
|
|
case DSG_FIXED:
|
|
if (ds->dsg_name) {
|
|
C_lae_dnam(ds->dsg_name, ds->dsg_offset);
|
|
break;
|
|
}
|
|
C_lal(ds->dsg_offset);
|
|
break;
|
|
|
|
case DSG_PFIXED:
|
|
ds->dsg_kind = DSG_FIXED;
|
|
CodeValue(ds, pointer_size);
|
|
break;
|
|
|
|
case DSG_INDEXED:
|
|
C_aar(word_size);
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeAddress)");
|
|
}
|
|
|
|
ds->dsg_offset = 0;
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
}
|
|
|
|
CodeFieldDesig(df, ds)
|
|
register struct def *df;
|
|
register struct desig *ds;
|
|
{
|
|
/* Generate code for a field designator. Only the code common for
|
|
address as well as value computation is generated, and the
|
|
resulting information on where to find the designator is placed
|
|
in "ds". "df" indicates the definition of the field.
|
|
*/
|
|
|
|
register struct withdesig *wds;
|
|
|
|
if (ds->dsg_kind == DSG_INIT) {
|
|
/* In a WITH statement. We must find the designator in the
|
|
WITH statement, and act as if the field is a selection
|
|
of this designator.
|
|
So, first find the right WITH statement, which is the
|
|
first one of the proper record type.
|
|
Notice that the proper record type is recognized by its
|
|
scope indication.
|
|
*/
|
|
wds = WithDesigs;
|
|
assert(wds != 0);
|
|
|
|
while (wds->w_scope != df->df_scope) {
|
|
wds = wds->w_next;
|
|
assert(wds != 0);
|
|
}
|
|
|
|
/* Found it. Now, act like it was a selection.
|
|
*/
|
|
*ds = wds->w_desig;
|
|
assert(ds->dsg_kind == DSG_PFIXED);
|
|
}
|
|
|
|
switch(ds->dsg_kind) {
|
|
case DSG_PLOADED:
|
|
case DSG_FIXED:
|
|
ds->dsg_offset += df->fld_off;
|
|
break;
|
|
|
|
case DSG_PFIXED:
|
|
case DSG_INDEXED:
|
|
CodeAddress(ds);
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
ds->dsg_offset = df->fld_off;
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeFieldDesig)");
|
|
}
|
|
}
|
|
|
|
CodeVarDesig(df, ds)
|
|
register struct def *df;
|
|
register struct desig *ds;
|
|
{
|
|
/* Generate code for a variable represented by a "def" structure.
|
|
Of course, there are numerous cases: the variable is local,
|
|
it is a value parameter, it is a var parameter, it is one of
|
|
those of an enclosing procedure, or it is global.
|
|
*/
|
|
register struct scope *sc = df->df_scope;
|
|
|
|
/* Selections from a module are handled earlier, when identifying
|
|
the variable, so ...
|
|
*/
|
|
assert(ds->dsg_kind == DSG_INIT);
|
|
|
|
df->df_flags |= D_USED;
|
|
if (df->var_addrgiven) {
|
|
/* the programmer specified an address in the declaration of
|
|
the variable. Generate code to push the address.
|
|
*/
|
|
CodeConst(df->var_off, pointer_size);
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
ds->dsg_offset = 0;
|
|
return;
|
|
}
|
|
|
|
if (df->var_name) {
|
|
/* this variable has been given a name, so it is global.
|
|
It is directly accessible.
|
|
*/
|
|
ds->dsg_name = df->var_name;
|
|
ds->dsg_offset = 0;
|
|
ds->dsg_kind = DSG_FIXED;
|
|
return;
|
|
}
|
|
|
|
if (sc->sc_level != proclevel) {
|
|
/* the variable is local to a statically enclosing procedure.
|
|
*/
|
|
assert(proclevel > sc->sc_level);
|
|
|
|
df->df_flags |= D_NOREG;
|
|
if (df->df_flags & (D_VARPAR|D_VALPAR)) {
|
|
/* value or var parameter
|
|
*/
|
|
C_lxa((arith) (proclevel - sc->sc_level));
|
|
if ((df->df_flags & D_VARPAR) ||
|
|
IsConformantArray(df->df_type)) {
|
|
/* var parameter
|
|
*/
|
|
C_adp(df->var_off);
|
|
C_loi(pointer_size);
|
|
ds->dsg_offset = 0;
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
return;
|
|
}
|
|
}
|
|
else C_lxl((arith) (proclevel - sc->sc_level));
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
ds->dsg_offset = df->var_off;
|
|
return;
|
|
}
|
|
|
|
/* Now, finally, we have a local variable or a local parameter
|
|
*/
|
|
if ((df->df_flags & D_VARPAR) || IsConformantArray(df->df_type)) {
|
|
/* a var parameter; address directly accessible.
|
|
*/
|
|
ds->dsg_kind = DSG_PFIXED;
|
|
}
|
|
else ds->dsg_kind = DSG_FIXED;
|
|
ds->dsg_offset =df->var_off;
|
|
}
|
|
|
|
CodeDesig(nd, ds)
|
|
register struct node *nd;
|
|
register struct desig *ds;
|
|
{
|
|
/* Generate code for a designator. Use divide and conquer
|
|
principle
|
|
*/
|
|
register struct def *df;
|
|
|
|
switch(nd->nd_class) { /* Divide */
|
|
case Def:
|
|
df = nd->nd_def;
|
|
|
|
df->df_flags |= D_USED;
|
|
switch(df->df_kind) {
|
|
case D_FIELD:
|
|
CodeFieldDesig(df, ds);
|
|
break;
|
|
|
|
case D_VARIABLE:
|
|
CodeVarDesig(df, ds);
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeDesig) Def");
|
|
}
|
|
break;
|
|
|
|
case LinkDef:
|
|
assert(nd->nd_symb == '.');
|
|
|
|
CodeDesig(nd->nd_left, ds);
|
|
CodeFieldDesig(nd->nd_def, ds);
|
|
break;
|
|
|
|
case Arrsel:
|
|
assert(nd->nd_symb == '[');
|
|
|
|
CodeDesig(nd->nd_left, ds);
|
|
CodeAddress(ds);
|
|
CodePExpr(nd->nd_right);
|
|
if (nd->nd_right->nd_type->tp_size > word_size) {
|
|
CodeCoercion(nd->nd_right->nd_type, int_type);
|
|
}
|
|
|
|
/* Now load address of descriptor
|
|
*/
|
|
if (IsConformantArray(nd->nd_left->nd_type)) {
|
|
assert(nd->nd_left->nd_class == Def);
|
|
|
|
df = nd->nd_left->nd_def;
|
|
if (proclevel > df->df_scope->sc_level) {
|
|
C_lxa((arith) (proclevel - df->df_scope->sc_level));
|
|
C_adp(df->var_off + pointer_size);
|
|
}
|
|
else C_lal(df->var_off + pointer_size);
|
|
}
|
|
else {
|
|
C_lae_dlb(nd->nd_left->nd_type->arr_descr, (arith) 0);
|
|
}
|
|
ds->dsg_kind = DSG_INDEXED;
|
|
break;
|
|
|
|
case Arrow:
|
|
assert(nd->nd_symb == '^');
|
|
|
|
CodeDesig(nd->nd_right, ds);
|
|
switch(ds->dsg_kind) {
|
|
case DSG_LOADED:
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
break;
|
|
|
|
case DSG_INDEXED:
|
|
case DSG_PLOADED:
|
|
case DSG_PFIXED:
|
|
CodeValue(ds, pointer_size);
|
|
ds->dsg_kind = DSG_PLOADED;
|
|
ds->dsg_offset = 0;
|
|
break;
|
|
|
|
case DSG_FIXED:
|
|
ds->dsg_kind = DSG_PFIXED;
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeDesig) Uoper");
|
|
}
|
|
break;
|
|
|
|
default:
|
|
crash("(CodeDesig) class");
|
|
}
|
|
}
|