2.11BSD/src/lib/pcc/local.c
# include "pass1.h"
/* this file contains code which is dependent on the target machine */
NODE *
cast( p, t ) register NODE *p; TWORD t; {
/* cast node p to type t */
p = buildtree( CAST, block( NAME, NIL, NIL, t, 0, (int)t ), p );
p->in.left->in.op = FREE;
p->in.op = FREE;
return( p->in.right );
}
NODE *
clocal(p) NODE *p; {
/* this is called to do local transformations on
an expression tree preparitory to its being
written out in intermediate code.
*/
/* the major essential job is rewriting the
automatic variables and arguments in terms of
REG and OREG nodes */
/* conversion ops which are not necessary are also clobbered here */
/* in addition, any special features (such as rewriting
exclusive or) are easily handled here as well */
register struct symtab *q;
register NODE *r;
register o;
register m, ml;
switch( o = p->in.op ){
case NAME:
if( p->tn.rval < 0 ) { /* already processed; ignore... */
return(p);
}
q = &stab[p->tn.rval];
switch( q->sclass ){
case AUTO:
case PARAM:
/* fake up a structure reference */
r = block( REG, NIL, NIL, PTR+STRTY, 0, 0 );
r->tn.lval = 0;
r->tn.rval = (q->sclass==AUTO?STKREG:ARGREG);
p = stref( block( STREF, r, p, 0, 0, 0 ) );
break;
case ULABEL:
case LABEL:
case STATIC:
if( q->slevel == 0 ) break;
p->tn.lval = 0;
p->tn.rval = -q->offset;
break;
case REGISTER:
p->in.op = REG;
p->tn.lval = 0;
p->tn.rval = q->offset;
break;
}
break;
case LT:
case LE:
case GT:
case GE:
if(ISPTR(p->in.left->in.type) || ISPTR(p->in.right->in.type)){
p->in.op += (ULT-LT);
}
break;
case PCONV:
/* do pointer conversions for char and longs */
ml = p->in.left->in.type;
if( ( ml==CHAR || ml==UCHAR || ml==LONG || ml==ULONG ) && p->in.left->in.op != ICON ) break;
/* pointers all have the same representation; the type is inherited */
p->in.left->in.type = p->in.type;
p->in.left->fn.cdim = p->fn.cdim;
p->in.left->fn.csiz = p->fn.csiz;
p->in.op = FREE;
return( p->in.left );
case SCONV:
m = (p->in.type == FLOAT || p->in.type == DOUBLE );
ml = (p->in.left->in.type == FLOAT || p->in.left->in.type == DOUBLE );
o = p->in.left->in.op;
if( (o == FCON || o == DCON) && ml && !m ) {
/* float type to int type */
r = block( ICON, (NODE *)NULL, (NODE *)NULL, LONG, 0, 0 );
if( o == FCON )
r->tn.lval = (long) p->in.left->fpn.fval;
else
r->tn.lval = (long) p->in.left->dpn.dval;
r->tn.rval = NONAME;
p->in.left->in.op = FREE;
p->in.left = r;
}
else
#ifdef SPRECC
if ( ml || m )
#else
if ( ml != m )
#endif
break;
/* now, look for conversions downwards */
m = p->in.type;
ml = p->in.left->in.type;
if( p->in.left->in.op == ICON ){ /* simulate the conversion here */
CONSZ val;
val = p->in.left->tn.lval;
switch( m ){
case CHAR:
p->in.left->tn.lval = (char) val;
break;
case UCHAR:
p->in.left->tn.lval = val & 0XFF;
break;
case UNSIGNED:
p->in.left->tn.lval = val & 0XFFFFL;
break;
case INT:
p->in.left->tn.lval = (int)val;
break;
}
p->in.left->in.type = m;
}
else {
/* meaningful ones are conversion of int to char, int to short,
and short to char, and unsigned version of them */
if( m==CHAR || m==UCHAR ){
if( ml==LONG || ml==ULONG ) break;
}
else if( m==INT || m==UNSIGNED ){
if( ml==LONG || ml==ULONG ) break;
}
else if( m==LONG || m==ULONG ){
if( ml!=LONG && ml!= ULONG ) break;
}
}
/* clobber conversion */
p->in.op = FREE;
return( p->in.left ); /* conversion gets clobbered */
case ASSIGN:
/* get rid of SCONV for assignments
from LONG -> CHAR|INT */
if( p->in.right->in.op == SCONV ) {
m = p->in.right->in.type;
ml = p->in.right->in.left->in.type;
if( ( m==LONG || m==ULONG ) &&
ml!=FLOAT && ml!=DOUBLE ) {
p->in.right->in.op = FREE;
p->in.right = p->in.right->in.left;
}
}
break;
case PVCONV:
case PMCONV:
if( p->in.right->in.op != ICON ) cerror( "bad conversion", 0);
p->in.op = FREE;
return( buildtree( o==PMCONV?MUL:DIV, p->in.left, p->in.right ) );
case PLUS:
case MINUS:
case LS:
case MUL:
/* optimize address calculations with long indexes */
if( ISPTR( p->in.type ) || ISARY( p->in.type ) ) {
if( p->in.left->in.type==LONG || p->in.left->in.type==ULONG )
p->in.left = cast( p->in.left, INT );
if( p->in.right->in.type==LONG || p->in.right->in.type==ULONG )
p->in.right = cast( p->in.right, INT );
}
break;
case FLD:
/* make sure that the second pass does not make the
descendant of a FLD operator into a doubly indexed OREG */
if( p->in.left->in.op == UNARY MUL
&& (r=p->in.left->in.left)->in.op == PCONV)
if( r->in.left->in.op == PLUS || r->in.left->in.op == MINUS )
if( ISPTR(r->in.type) ) {
if( ISUNSIGNED(p->in.left->in.type) )
p->in.left->in.type = UCHAR;
else
p->in.left->in.type = CHAR;
}
break;
}
return(p);
}
andable( p ) NODE *p; {
return(1); /* all names can have & taken on them */
}
cendarg(){ /* at the end of the arguments of a ftn, set the automatic offset */
autooff = AUTOINIT;
}
cisreg( t ) TWORD t; { /* is an automatic variable of type t OK for a register variable */
#ifdef TRUST_REG_CHAR_AND_REG_SHORT
if( t==INT || t==UNSIGNED /* tbl */
|| t==CHAR || t==UCHAR || t==SHORT /* tbl */
|| t==USHORT || ISPTR(t)) return(1); /* tbl */
#else
if( t==INT || t==UNSIGNED /* wnj */
#ifdef SPRECC
|| t==FLOAT
#endif
|| ISPTR(t)) return (1); /* wnj */
#endif
return(0);
}
NODE *
offcon( off, t, d, s ) OFFSZ off; TWORD t; {
/* return a node, for structure references, which is suitable for
being added to a pointer of type t, in order to be off bits offset
into a structure */
register NODE *p;
/* t, d, and s are the type, dimension offset, and sizeoffset */
/* in general they are necessary for offcon, but not on H'well */
p = bcon(0);
p->tn.lval = off/SZCHAR;
return(p);
}
static inwd /* current bit offsed in word */;
static word /* word being built from fields */;
incode( p, sz ) register NODE *p; {
/* generate initialization code for assigning a constant c
to a field of width sz */
/* we assume that the proper alignment has been obtained */
/* inoff is updated to have the proper final value */
/* we also assume sz < SZINT */
if((sz+inwd) > SZINT) cerror("incode: field > int");
word |= ((unsigned)(p->tn.lval<<(16-sz))) >> (16-sz-inwd);
inwd += sz;
inoff += sz;
if(inoff%SZINT == 0) {
printf( " %o\n", word);
word = inwd = 0;
}
}
fincode( d, sz ) double d; {
/* output code to initialize space of size sz to the value d */
/* the proper alignment has been obtained */
/* inoff is updated to have the proper final value */
/* on the target machine, write it out in octal! */
register int *mi = (int *)&d;
if( sz==SZDOUBLE )
printf( " %o; %o; %o; %o\n", mi[0], mi[1], mi[2], mi[3] );
else
printf( " %o; %o\n", mi[0], mi[1] );
inoff += sz;
}
cinit( p, sz ) NODE *p; {
NODE *l;
/*
* as a favor (?) to people who want to write
* int i = 9600/134.5;
* we will, under the proper circumstances, do
* a coersion here.
*/
switch (p->in.type) {
case INT:
case UNSIGNED:
l = p->in.left;
if (l->in.op != SCONV ||
(l->in.left->tn.op != DCON && l->in.left->tn.op != FCON))
break;
l->in.op = FREE;
l = l->in.left;
l->tn.lval = l->tn.op == DCON ? (long)(l->dpn.dval) :
(long)(l->fpn.fval);
l->tn.rval = NONAME;
l->tn.op = ICON;
l->tn.type = INT;
p->in.left = l;
break;
}
/* arrange for the initialization of p into a space of size sz */
/* the proper alignment has been opbtained */
/* inoff is updated to have the proper final value */
ecode( p );
inoff += sz;
}
vfdzero( n ){ /* define n bits of zeros in a vfd */
if( n <= 0 ) return;
inwd += n;
inoff += n;
if( inoff%ALINT ==0 ) {
printf( " %o\n", word );
word = inwd = 0;
}
}
char *
exname( p ) char *p; {
/* make a name look like an external name in the local machine */
#ifndef FLEXNAMES
static char text[NCHNAM+1];
#else
static char text[256+1];
#endif
register i;
text[0] = '_';
#ifndef FLEXNAMES
for( i=1; *p&&i<NCHNAM; ++i )
#else
for( i=1; *p; ++i )
#endif
text[i] = *p++;
text[i] = '\0';
#ifndef FLEXNAMES
text[NCHNAM] = '\0'; /* truncate */
#endif
return( text );
}
ctype( type ) TWORD type;
{ /* map types which are not defined on the local machine */
switch( BTYPE(type) ){
case SHORT:
MODTYPE(type,INT);
break;
case USHORT:
MODTYPE(type,UNSIGNED);
}
return( type );
}
noinit() { /* curid is a variable which is defined but
is not initialized (and not a function );
This routine returns the stroage class for an uninitialized declaration */
return(EXTERN);
}
commdec( id ){ /* make a common declaration for id, if reasonable */
register struct symtab *q;
OFFSZ off, tsize();
q = &stab[id];
printf( " .comm %s,", exname( q->sname ) );
off = tsize( q->stype, q->dimoff, q->sizoff );
printf( CONFMT, off/SZCHAR );
printf( ".\n" );
}
isitlong( cb, ce ){ /* is lastcon to be long or short */
/* cb is the first character of the representation, ce the last */
if( ce == 'l' || ce == 'L' ||
lastcon >= (1L << (SZINT-1) ) ) return (1);
return(0);
}
isitfloat( s ) char *s; {
union cvt {
double d;
int n[4];
} cvt;
double atof();
/* avoid floating point exception for double -> float conversions */
dcon = cvt.d = atof(s);
if( cvt.n[1] == 0 ){
fcon = dcon;
return( FCON );
}
return( DCON );
}
ecode( p ) NODE *p; {
/* walk the tree and write out the nodes.. */
if( nerrors ) return;
p2tree( p );
p2compile( p );
}
#ifndef ONEPASS
tlen(p) NODE *p;
{
switch(p->in.type) {
case CHAR:
case UCHAR:
return(1);
case LONG:
case ULONG:
case FLOAT:
return(4);
case DOUBLE:
return(8);
default:
return(2);
}
}
#endif