ack/lang/m2/comp/code.c
1987-11-09 16:11:04 +00:00

1091 lines
20 KiB
C

/*
* (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
*/
/* C O D E G E N E R A T I O N R O U T I N E S */
/* $Header$ */
/* Code generation for expressions and coercions
*/
#include "debug.h"
#include <em_arith.h>
#include <em_label.h>
#include <em_code.h>
#include <em_abs.h>
#include <assert.h>
#include <alloc.h>
#include "type.h"
#include "LLlex.h"
#include "def.h"
#include "scope.h"
#include "desig.h"
#include "node.h"
#include "Lpars.h"
#include "standards.h"
#include "walk.h"
extern char *long2str();
extern char *symbol2str();
extern int proclevel;
extern char options[];
int fp_used;
STATIC char *
NameOfProc(df)
register t_def *df;
{
assert(df->df_kind & (D_PROCHEAD|D_PROCEDURE));
if (df->df_kind == D_PROCEDURE) {
return df->prc_vis->sc_scope->sc_name;
}
return df->for_name;
}
CodeConst(cst, size)
arith cst;
int size;
{
/* Generate code to push constant "cst" with size "size"
*/
if (size <= (int) word_size) {
C_loc(cst);
}
else if (size == (int) dword_size) {
C_ldc(cst);
}
else {
crash("(CodeConst)");
/*
C_df_dlb(++data_label);
C_rom_icon(long2str((long) cst), (arith) size);
c_lae_dlb(data_label);
C_loi((arith) size);
*/
}
}
CodeString(nd)
register t_node *nd;
{
if (nd->nd_type->tp_fund != T_STRING) {
/* Character constant */
C_loc(nd->nd_INT);
return;
}
C_df_dlb(++data_label);
C_rom_scon(nd->nd_STR, WA(nd->nd_SLE + 1));
c_lae_dlb(data_label);
}
CodeExpr(nd, ds, true_label, false_label)
register t_node *nd;
register t_desig *ds;
label true_label, false_label;
{
register t_type *tp = nd->nd_type;
if (tp->tp_fund == T_REAL) fp_used = 1;
switch(nd->nd_class) {
case Def:
if (nd->nd_def->df_kind & (D_PROCEDURE|D_PROCHEAD)) {
C_lpi(NameOfProc(nd->nd_def));
ds->dsg_kind = DSG_LOADED;
break;
}
/* Fall through */
case Link:
case Arrsel:
case Arrow:
CodeDesig(nd, ds);
break;
case Oper:
CodeOper(nd, true_label, false_label);
ds->dsg_kind = DSG_LOADED;
true_label = NO_LABEL;
break;
case Uoper:
CodeUoper(nd);
ds->dsg_kind = DSG_LOADED;
break;
case Value:
switch(nd->nd_symb) {
case REAL:
C_df_dlb(++data_label);
C_rom_fcon(nd->nd_REL, tp->tp_size);
c_lae_dlb(data_label);
C_loi(tp->tp_size);
break;
case STRING:
CodeString(nd);
break;
case INTEGER:
CodeConst(nd->nd_INT, (int) (tp->tp_size));
break;
default:
crash("Value error");
}
ds->dsg_kind = DSG_LOADED;
break;
case Call:
CodeCall(nd);
ds->dsg_kind = DSG_LOADED;
break;
case Set: {
register unsigned i = (unsigned) (tp->tp_size) / (int) word_size;
register arith *st = nd->nd_set + i;
ds->dsg_kind = DSG_LOADED;
for (; i; i--) {
C_loc(*--st);
}
FreeSet(nd->nd_set);
CodeSet(nd);
}
break;
default:
crash("(CodeExpr) bad node type");
}
if (true_label != NO_LABEL) {
/* Only for boolean expressions
*/
CodeValue(ds, tp);
C_zne(true_label);
C_bra(false_label);
}
}
CodeCoercion(t1, t2)
register t_type *t1, *t2;
{
register int fund1, fund2;
arith sz1 = t1->tp_size;
t1 = BaseType(t1);
t2 = BaseType(t2);
switch(fund1 = t1->tp_fund) {
case T_WORD:
fund1 = T_INTEGER;
break;
case T_CHAR:
case T_EQUAL:
case T_ENUMERATION:
case T_POINTER:
fund1 = T_CARDINAL;
break;
}
switch(fund2 = t2->tp_fund) {
case T_WORD:
fund2 = T_INTEGER;
break;
case T_CHAR:
case T_EQUAL:
case T_ENUMERATION:
case T_POINTER:
fund2 = T_CARDINAL;
break;
}
switch(fund1) {
case T_INTEGER:
if (sz1 < word_size) {
c_loc((int)sz1);
c_loc((int) word_size);
C_cii();
}
switch(fund2) {
case T_INTEGER:
#ifndef SQUEEZE
if (t2->tp_size != t1->tp_size)
#endif
{
c_loc((int)(t1->tp_size));
c_loc((int)(t2->tp_size));
C_cii();
}
break;
case T_CARDINAL:
#ifndef SQUEEZE
if (t1->tp_size != word_size)
#endif
{
c_loc((int)(t1->tp_size));
c_loc((int) word_size);
C_ciu();
}
break;
case T_REAL:
c_loc((int)(t1->tp_size));
c_loc((int)(t2->tp_size));
C_cif();
break;
default:
crash("Funny integer conversion");
}
break;
case T_CARDINAL:
case T_INTORCARD:
switch(fund2) {
case T_CARDINAL:
case T_INTORCARD:
if (t2->tp_size > word_size) {
c_loc((int) word_size);
c_loc((int)(t2->tp_size));
C_cuu();
}
break;
case T_INTEGER:
if (fund1 == T_CARDINAL
#ifndef SQUEEZE
|| t2->tp_size != word_size
#endif
) {
c_loc((int) word_size);
c_loc((int)(t2->tp_size));
C_cui();
}
break;
case T_REAL:
c_loc((int) word_size);
c_loc((int)(t2->tp_size));
C_cuf();
break;
default:
crash("Funny cardinal conversion");
}
break;
case T_REAL:
switch(fund2) {
case T_REAL:
#ifndef SQUEEZE
if (t2->tp_size != t1->tp_size)
#endif
{
c_loc((int)(t1->tp_size));
c_loc((int)(t2->tp_size));
C_cff();
}
break;
case T_INTEGER:
c_loc((int)(t1->tp_size));
c_loc((int)(t2->tp_size));
C_cfi();
break;
case T_CARDINAL:
if (! options['R']) {
label lb = ++text_label;
C_dup(t1->tp_size);
C_zrf(t1->tp_size);
C_cmf(t1->tp_size);
C_zge(lb);
c_loc(ECONV);
C_trp();
C_df_ilb(lb);
}
c_loc((int)(t1->tp_size));
c_loc((int)(t2->tp_size));
C_cfu();
break;
default:
crash("Funny REAL conversion");
}
break;
}
}
CodeCall(nd)
register t_node *nd;
{
/* Generate code for a procedure call. Checking of parameters
and result is already done.
*/
register t_node *left = nd->nd_left;
register t_node *right = nd->nd_right;
register t_type *result_tp;
if (left->nd_type == std_type) {
CodeStd(nd);
return;
}
if (IsCast(left)) {
/* it was just a cast. Simply ignore it
*/
CodePExpr(right->nd_left);
*nd = *(right->nd_left);
nd->nd_type = left->nd_def->df_type;
return;
}
assert(IsProcCall(left));
if (right) {
CodeParameters(ParamList(left->nd_type), right);
}
switch(left->nd_class) {
case Def: {
if (left->nd_def->df_kind & (D_PROCEDURE|D_PROCHEAD)) {
int level = left->nd_def->df_scope->sc_level;
if (level > 0) {
C_lxl((arith) (proclevel - level));
}
C_cal(NameOfProc(left->nd_def));
break;
}}
/* Fall through */
default:
CodePExpr(left);
C_cai();
}
C_asp(left->nd_type->prc_nbpar);
if (result_tp = ResultType(left->nd_type)) {
arith sz = WA(result_tp->tp_size);
if (IsConstructed(result_tp)) {
C_lfr(pointer_size);
C_loi(sz);
}
else C_lfr(sz);
}
}
CodeParameters(param, arg)
t_param *param;
t_node *arg;
{
register t_type *tp;
register t_node *left;
register t_type *left_type;
assert(param != 0 && arg != 0);
if (param->par_next) {
CodeParameters(param->par_next, arg->nd_right);
}
tp = TypeOfParam(param);
left = arg->nd_left;
left_type = left->nd_type;
if (IsConformantArray(tp)) {
register t_type *elem = tp->arr_elem;
C_loc(tp->arr_elsize);
if (IsConformantArray(left_type)) {
DoHIGH(left->nd_def);
if (elem->tp_size != left_type->arr_elem->tp_size) {
/* This can only happen if the formal type is
ARRAY OF (WORD|BYTE)
*/
C_loc(left_type->arr_elem->tp_size);
C_mli(word_size);
if (elem == word_type) {
c_loc((int) word_size - 1);
C_adi(word_size);
c_loc((int) word_size);
C_dvi(word_size);
}
else {
assert(elem == byte_type);
}
}
}
else if (left->nd_symb == STRING) {
C_loc(left->nd_SLE - 1);
}
else if (elem == word_type) {
C_loc((left_type->tp_size+word_size-1) / word_size - 1);
}
else if (elem == byte_type) {
C_loc(left_type->tp_size - 1);
}
else {
arith lb, ub;
getbounds(IndexType(left_type), &lb, &ub);
C_loc(ub - lb);
}
c_loc(0);
if (left->nd_symb == STRING) {
CodeString(left);
}
else switch(left->nd_class) {
case Arrsel:
case Arrow:
case Def:
CodeDAddress(left);
break;
default:{
arith tmp, TmpSpace();
CodePExpr(left);
tmp = TmpSpace(left->nd_type->tp_size, left->nd_type->tp_align);
C_lal(tmp);
C_sti(WA(left->nd_type->tp_size));
C_lal(tmp);
}
break;
}
return;
}
if (IsVarParam(param)) {
CodeDAddress(left);
return;
}
if (left_type->tp_fund == T_STRING) {
CodePString(left, tp);
return;
}
CodePExpr(left);
}
CodePString(nd, tp)
t_node *nd;
t_type *tp;
{
arith szarg = WA(nd->nd_type->tp_size);
register arith zersz = WA(tp->tp_size) - szarg;
if (zersz) {
/* null padding required */
assert(zersz > 0);
C_zer(zersz);
}
CodeString(nd); /* push address of string */
C_loi(szarg);
}
CodeStd(nd)
t_node *nd;
{
register t_node *arg = nd->nd_right;
register t_node *left = 0;
register t_type *tp;
int std = nd->nd_left->nd_def->df_value.df_stdname;
if (arg) {
left = arg->nd_left;
tp = BaseType(left->nd_type);
arg = arg->nd_right;
}
switch(std) {
case S_ABS:
CodePExpr(left);
if (tp->tp_fund == T_INTEGER) {
if (tp->tp_size == int_size) C_cal("_absi");
else C_cal("_absl");
}
else if (tp->tp_fund == T_REAL) {
if (tp->tp_size == float_size) C_cal("_absf");
else C_cal("_absd");
}
C_asp(tp->tp_size);
C_lfr(tp->tp_size);
break;
case S_CAP:
CodePExpr(left);
c_loc(0137); /* ASCII assumed */
C_and(word_size);
break;
case S_HIGH:
assert(IsConformantArray(tp));
DoHIGH(left->nd_def);
break;
case S_SIZE:
case S_TSIZE:
assert(IsConformantArray(tp));
DoHIGH(left->nd_def);
C_inc();
C_loc(tp->arr_elem->tp_size);
C_mlu(word_size);
break;
case S_ODD:
CodePExpr(left);
if (tp->tp_size == word_size) {
c_loc(1);
C_and(word_size);
}
else {
assert(tp->tp_size == dword_size);
C_ldc((arith) 1);
C_and(dword_size);
C_ior(word_size);
}
break;
case S_ADR:
CodeDAddress(left);
break;
case S_DEC:
case S_INC: {
register arith size;
size = left->nd_type->tp_size;
if (size < word_size) size = word_size;
CodePExpr(left);
CodeCoercion(left->nd_type, tp);
if (arg) {
CodePExpr(arg->nd_left);
CodeCoercion(arg->nd_left->nd_type, tp);
}
else {
c_loc(1);
CodeCoercion(intorcard_type, tp);
}
if (std == S_DEC) {
if (tp->tp_fund == T_INTEGER) C_sbi(size);
else C_sbu(size);
}
else {
if (tp->tp_fund == T_INTEGER) C_adi(size);
else C_adu(size);
}
if (size == word_size) {
RangeCheck(left->nd_type, tp->tp_fund == T_INTEGER ?
int_type : card_type);
}
CodeDStore(left);
break;
}
case S_HALT:
C_cal("_halt");
break;
case S_INCL:
case S_EXCL:
CodePExpr(left);
CodePExpr(arg->nd_left);
C_loc(tp->set_low);
C_sbi(word_size);
C_set(tp->tp_size);
if (std == S_INCL) {
C_ior(tp->tp_size);
}
else {
C_com(tp->tp_size);
C_and(tp->tp_size);
}
CodeDStore(left);
break;
default:
crash("(CodeStd)");
}
}
RangeCheck(tpl, tpr)
register t_type *tpl, *tpr;
{
/* Generate a range check if neccessary
*/
arith llo, lhi, rlo, rhi;
if (options['R']) return;
if (bounded(tpl)) {
/* in this case we might need a range check */
if (!bounded(tpr)) {
/* yes, we need one */
genrck(tpl);
return;
}
/* both types are restricted. check the bounds
to see wether we need a range check.
We don't need one if the range of values of the
right hand side is a subset of the range of values
of the left hand side.
*/
getbounds(tpl, &llo, &lhi);
getbounds(tpr, &rlo, &rhi);
if (llo > rlo || lhi < rhi) {
genrck(tpl);
}
return;
}
if (tpl->tp_size <= tpr->tp_size &&
((tpl->tp_fund == T_INTEGER && tpr == card_type) ||
(tpr->tp_fund == T_INTEGER && tpl == card_type))) {
label lb = ++text_label;
C_dup(word_size);
C_zge(lb);
c_loc(ECONV);
C_trp();
C_df_ilb(lb);
}
}
Operands(leftop, rightop)
register t_node *leftop, *rightop;
{
CodePExpr(leftop);
CodePExpr(rightop);
}
CodeOper(expr, true_label, false_label)
register t_node *expr; /* the expression tree itself */
label true_label;
label false_label; /* labels to jump to in logical expr's */
{
register t_node *leftop = expr->nd_left;
register t_node *rightop = expr->nd_right;
register t_type *tp = expr->nd_type;
switch (expr->nd_symb) {
case '+':
Operands(leftop, rightop);
switch (tp->tp_fund) {
case T_INTEGER:
C_adi(tp->tp_size);
break;
case T_REAL:
C_adf(tp->tp_size);
break;
case T_POINTER:
case T_EQUAL:
case T_CARDINAL:
case T_INTORCARD:
C_adu(tp->tp_size);
break;
case T_SET:
C_ior(tp->tp_size);
break;
default:
crash("bad type +");
}
break;
case '-':
Operands(leftop, rightop);
switch (tp->tp_fund) {
case T_INTEGER:
C_sbi(tp->tp_size);
break;
case T_REAL:
C_sbf(tp->tp_size);
break;
case T_POINTER:
case T_EQUAL:
case T_CARDINAL:
case T_INTORCARD:
C_sbu(tp->tp_size);
break;
case T_SET:
C_com(tp->tp_size);
C_and(tp->tp_size);
break;
default:
crash("bad type -");
}
break;
case '*':
Operands(leftop, rightop);
switch (tp->tp_fund) {
case T_INTEGER:
C_mli(tp->tp_size);
break;
case T_POINTER:
case T_EQUAL:
case T_CARDINAL:
case T_INTORCARD:
C_mlu(tp->tp_size);
break;
case T_REAL:
C_mlf(tp->tp_size);
break;
case T_SET:
C_and(tp->tp_size);
break;
default:
crash("bad type *");
}
break;
case '/':
Operands(leftop, rightop);
switch (tp->tp_fund) {
case T_REAL:
C_dvf(tp->tp_size);
break;
case T_SET:
C_xor(tp->tp_size);
break;
default:
crash("bad type /");
}
break;
case DIV:
Operands(leftop, rightop);
switch(tp->tp_fund) {
case T_INTEGER:
C_dvi(tp->tp_size);
break;
case T_POINTER:
case T_EQUAL:
case T_CARDINAL:
case T_INTORCARD:
C_dvu(tp->tp_size);
break;
default:
crash("bad type DIV");
}
break;
case MOD:
Operands(leftop, rightop);
switch(tp->tp_fund) {
case T_INTEGER:
C_rmi(tp->tp_size);
break;
case T_POINTER:
case T_EQUAL:
case T_CARDINAL:
case T_INTORCARD:
C_rmu(tp->tp_size);
break;
default:
crash("bad type MOD");
}
break;
case '<':
case LESSEQUAL:
case '>':
case GREATEREQUAL:
case '=':
case '#':
Operands(leftop, rightop);
tp = BaseType(leftop->nd_type);
if (tp == intorcard_type) tp = BaseType(rightop->nd_type);
switch (tp->tp_fund) {
case T_INTEGER:
C_cmi(tp->tp_size);
break;
case T_POINTER:
case T_HIDDEN:
case T_EQUAL:
case T_CARDINAL:
case T_INTORCARD:
C_cmu(tp->tp_size);
break;
case T_ENUMERATION:
case T_CHAR:
C_cmu(word_size);
break;
case T_REAL:
C_cmf(tp->tp_size);
break;
case T_SET:
if (expr->nd_symb == GREATEREQUAL) {
/* A >= B is the same as A equals A + B
*/
C_dup(2*tp->tp_size);
C_asp(tp->tp_size);
C_ior(tp->tp_size);
expr->nd_symb = '=';
}
else if (expr->nd_symb == LESSEQUAL) {
/* A <= B is the same as A - B = {}
*/
C_com(tp->tp_size);
C_and(tp->tp_size);
C_zer(tp->tp_size);
expr->nd_symb = '=';
}
C_cms(tp->tp_size);
break;
default:
crash("bad type COMPARE");
}
if (true_label != NO_LABEL) {
compare(expr->nd_symb, true_label);
C_bra(false_label);
break;
}
truthvalue(expr->nd_symb);
break;
case IN:
/* In this case, evaluate right hand side first! The
INN instruction expects the bit number on top of the
stack
*/
CodePExpr(rightop);
CodePExpr(leftop);
C_loc(rightop->nd_type->set_low);
C_sbi(word_size);
C_inn(rightop->nd_type->tp_size);
if (true_label != NO_LABEL) {
C_zne(true_label);
C_bra(false_label);
}
break;
case OR:
case AND: {
label l_maybe = ++text_label, l_end;
t_desig *Des = new_desig();
int genlabels = 0;
if (true_label == NO_LABEL) {
genlabels = 1;
true_label = ++text_label;
false_label = ++text_label;
l_end = ++text_label;
}
if (expr->nd_symb == OR) {
CodeExpr(leftop, Des, true_label, l_maybe);
}
else CodeExpr(leftop, Des, l_maybe, false_label);
C_df_ilb(l_maybe);
free_desig(Des);
Des = new_desig();
CodeExpr(rightop, Des, true_label, false_label);
if (genlabels) {
C_df_ilb(true_label);
c_loc(1);
C_bra(l_end);
C_df_ilb(false_label);
c_loc(0);
C_df_ilb(l_end);
}
free_desig(Des);
break;
}
default:
crash("(CodeOper) Bad operator %s\n",symbol2str(expr->nd_symb));
}
}
/* compare() serves as an auxiliary function of CodeOper */
compare(relop, lbl)
int relop;
register label lbl;
{
switch (relop) {
case '<':
C_zlt(lbl);
break;
case LESSEQUAL:
C_zle(lbl);
break;
case '>':
C_zgt(lbl);
break;
case GREATEREQUAL:
C_zge(lbl);
break;
case '=':
C_zeq(lbl);
break;
case '#':
C_zne(lbl);
break;
default:
crash("(compare)");
}
}
/* truthvalue() serves as an auxiliary function of CodeOper */
truthvalue(relop)
int relop;
{
switch (relop) {
case '<':
C_tlt();
break;
case LESSEQUAL:
C_tle();
break;
case '>':
C_tgt();
break;
case GREATEREQUAL:
C_tge();
break;
case '=':
C_teq();
break;
case '#':
C_tne();
break;
default:
crash("(truthvalue)");
}
}
CodeUoper(nd)
register t_node *nd;
{
register t_type *tp = nd->nd_type;
CodePExpr(nd->nd_right);
switch(nd->nd_symb) {
case NOT:
C_teq();
break;
case '-':
switch(tp->tp_fund) {
case T_INTEGER:
case T_INTORCARD:
C_ngi(tp->tp_size);
break;
case T_REAL:
C_ngf(tp->tp_size);
break;
default:
crash("Bad operand to unary -");
}
break;
case COERCION:
CodeCoercion(nd->nd_right->nd_type, tp);
RangeCheck(tp, nd->nd_right->nd_type);
break;
default:
crash("Bad unary operator");
}
}
CodeSet(nd)
register t_node *nd;
{
register t_type *tp = nd->nd_type;
nd = nd->nd_right;
while (nd) {
assert(nd->nd_class == Link && nd->nd_symb == ',');
if (nd->nd_left) CodeEl(nd->nd_left, tp);
nd = nd->nd_right;
}
}
CodeEl(nd, tp)
register t_node *nd;
register t_type *tp;
{
register t_type *eltype = ElementType(tp);
if (nd->nd_class == Link && nd->nd_symb == UPTO) {
C_loc(tp->set_low);
C_loc(tp->tp_size); /* push size */
if (eltype->tp_fund == T_SUBRANGE) {
C_loc(eltype->sub_ub);
}
else C_loc((arith) (eltype->enm_ncst - 1));
Operands(nd->nd_left, nd->nd_right);
C_cal("_LtoUset"); /* library routine to fill set */
C_asp(5 * word_size);
}
else {
CodePExpr(nd);
C_loc(tp->set_low);
C_sbi(word_size);
C_set(tp->tp_size);
C_ior(tp->tp_size);
}
}
CodePExpr(nd)
register t_node *nd;
{
/* Generate code to push the value of the expression "nd"
on the stack.
*/
register t_desig *designator = new_desig();
CodeExpr(nd, designator, NO_LABEL, NO_LABEL);
CodeValue(designator, nd->nd_type);
free_desig(designator);
}
CodeDAddress(nd)
t_node *nd;
{
/* Generate code to push the address of the designator "nd"
on the stack.
*/
register t_desig *designator = new_desig();
ChkForFOR(nd);
CodeDesig(nd, designator);
CodeAddress(designator);
free_desig(designator);
}
CodeDStore(nd)
register t_node *nd;
{
/* Generate code to store the expression on the stack into the
designator "nd".
*/
register t_desig *designator = new_desig();
ChkForFOR(nd);
CodeDesig(nd, designator);
CodeStore(designator, nd->nd_type);
free_desig(designator);
}
DoHIGH(df)
register t_def *df;
{
/* Get the high index of a conformant array, indicated by "nd".
The high index is the second field in the descriptor of
the array, so it is easily found.
*/
register arith highoff;
assert(df->df_kind == D_VARIABLE);
assert(IsConformantArray(df->df_type));
highoff = df->var_off /* base address and descriptor */
+ 2 * word_size; /* skip base and first field of
descriptor
*/
if (df->df_scope->sc_level < proclevel) {
C_lxa((arith) (proclevel - df->df_scope->sc_level));
C_lof(highoff);
}
else C_lol(highoff);
}
#ifdef SQUEEZE
c_loc(n)
{
C_loc((arith) n);
}
c_lae_dlb(l)
label l;
{
C_lae_dlb(l, (arith) 0);
}
#endif