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BSD 4_3_Tahoe release
[unix-history] / usr / src / bin / as / as.tahoe / ascode.c
/*
* Copyright (c) 1982 Regents of the University of California
*/
#ifndef lint
static char sccsid[] = "@(#)ascode.c 4.11 6/30/83";
#endif not lint
#include <stdio.h>
#include "as.h"
#include "assyms.h"
insout(opcode, ap, nact)
u_char opcode;
struct arg *ap;
int nact;
{
int jxxflg;
reg struct instab *ip; /* the instruction */
reg struct arg *ap_walk; /* actual param walk */
reg int i;
reg int ap_type; /* actual param type */
reg int ap_type_mask; /* masked actual param */
reg int argtype;
jxxflg = nact;
if (nact < 0)
nact = -nact;
if (passno == 1) {
ip = ITABFETCH(opcode & 0xFF);
if (nact < ip->i_nargs)
yyerror("Too few arguments");
if (nact > ip->i_nargs) {
yyerror("Too many arguments");
nact = ip->i_nargs;
}
/*
* Check argument compatability with instruction template
*/
for (ap_walk = ap, i = 1; i <= nact; ap_walk++, i++){
ap_type = ap_walk->a_atype;
ap_type_mask = ap_type & AMASK;
/*
* The switch value is >> by TYPLG so that the switch
* code is dense, not implemented as a sequence
* of branches but implemented as a casel.
* In addition, cases ACCI and ACCR are added to force
* dense switch code.
* switch on the type of fp
*/
argtype = fetcharg(ip, i-1);
switch( (argtype & ACCESSMASK) >> TYPLG){
case ACCI >> TYPLG:
break;
case ACCR >> TYPLG:
if ((argtype == A_RQ) &&
(ap_type_mask == AREG) &&
(ap_walk->a_areg1 & 0x01)) {
yyerror("arg %d, register must be even",i);
return;
}
if (ap_type_mask == ADECR)
{
yyerror("arg %d, a source arg cant be auto decrement",i);
return;
}
if (argtype == A_RD)
{
if (ap_type_mask == AIMM)
if ( !(ap_type&ASTAR))
{
yyerror("arg %d, cant be immediate data",i);
return;
}
if ((argtype == A_RD) &&
((ap_type_mask == AINCR) ||
(ap_type_mask == ADECR)))
{
yyerror("arg %d, cant be auto increment/decrement",i);
return;
}
if ((argtype == A_RD) &&
(ap_type_mask == AREG) &&
(ap_walk->a_areg1 & 0x01)) {
yyerror("arg %d, register must be even",i);
return;
}
}
break;
case ACCB >> TYPLG:
if ( ap_type_mask != AEXP)
{
yyerror("arg %d, branch displacement must be an expression",i);
return;
}
break;
case ACCA >> TYPLG:
switch(ap_type_mask){
case AREG: yyerror("arg %d, addressing a register",i);
return;
case AIMM: if ( !(ap_type & ASTAR) ){
yyerror("arg %d, addressing an immediate operand",i);
return;
}
}
break;
case ACCM >> TYPLG:
case ACCW >> TYPLG:
if ((argtype == A_WQ) &&
(ap_type_mask == AREG) &&
(ap_walk->a_areg1 & 0x01)) {
yyerror("arg %d, register must be even",i);
return;
}
switch(ap_type_mask){
case AIMM: if (!(ap_type&ASTAR)) {
yyerror("arg %d, modifying a constant",i);
return;
}
case AINCR:
yyerror("arg %d, a destination arg cant be auto increment",i);
return;
}
break;
} /* end of the switch on fp_type */
if (ap_type & AINDX) {
if (ap_walk->a_areg2==0xF) {
yyerror("arg %d, PC used as index",i);
return;
}
if (ap_walk->a_areg2==0xE) {
yyerror("arg %d, SP used as index",i);
return;
}
switch(ap_type_mask){
case AREG: yyerror("arg %d, indexing the register file",i);
return;
case AIMM: yyerror("arg %d, indexing a constant",i);
return;
case ADECR:
case AINCR: if (ap_walk->a_areg1==ap_walk->a_areg2) {
yyerror("arg %d, indexing with modified register",i);
return;
}
break;
} /* end of switch on ap_type_mask */
} /* end of AINDX */
}
} /* both passes here */
if (jxxflg < 0)
ijxout(opcode, ap, nact);
else
putins(opcode, ap, nact);
}
extern int d124;
putins(opcode, ap, n)
u_char opcode;
register struct arg *ap;
int n; /* Must be positive */
{
reg struct exp *xp;
reg int argtype;
int i;
int reloc_how;
#ifdef DEBUG
fflush(stdout);
#endif
if (passno == 2)
goto PASS2;
dotp->e_xvalue += n+1; /* at least one byte per arg */
for (i=0; i<n; i++,ap++) { /* some args take more than 1 byte */
argtype = ap->a_atype;
if (argtype & AINDX)
dotp->e_xvalue++;
/*
* This switch has been fixed by enumerating the no action
* alternatives (those that have 1 one byte of code)
* so that a casel instruction is emitted.
*/
switch (argtype&~(AINDX|ASTAR)) {
case AREG:
case ABASE:
case ADECR:
case AINCR:
break;
case AEXP:
argtype = fetcharg(ITABFETCH(opcode), i);
if (argtype == A_BB)
break;
if (argtype == A_BW){
dotp->e_xvalue++;
break;
}
/*
* Reduces to PC relative
*/
dotp->e_xvalue += ap->a_dispsize;
break;
case ADISP:
xp=ap->a_xp;
if ((xp->e_xtype&XTYPE)!=XABS || xp->e_xtype&XFORW){
dotp->e_xvalue += ap->a_dispsize;
break;
}
if (xp->e_xvalue==0 && !(argtype&ASTAR))
break;
dotp->e_xvalue ++;
if (ISBYTE(xp->e_xvalue))
break;
dotp->e_xvalue ++;
if (ISWORD(xp->e_xvalue))
break;
dotp->e_xvalue += 2;
break;
case AIMM:
if (ap->a_atype&ASTAR) {
argtype=TYPL;
} else {
argtype = fetcharg(ITABFETCH(opcode), i);
if (argtype&ACCA)
argtype = TYPL;
else
argtype &= TYPMASK;
xp = ap->a_xp;
if ( ((xp->e_xtype&XTYPE)==XABS)
&& (!(xp->e_xtype&XFORW))
&& (argtype != TYPD)
&& (argtype != TYPF))
{
if ((xp->e_xvalue>=0)
&& (xp->e_xvalue<=63))
break;
if (ISBYTE(xp->e_xvalue))
argtype = TYPB;
else
if (ISWORD(xp->e_xvalue))
argtype = TYPW;
else
argtype = TYPL;
}
else
argtype = TYPL;
}
switch (argtype) {
case TYPD:
case TYPF:
if (!(slitflt(xp)))
return;
case TYPQ:
case TYPL:
case TYPW:
case TYPB:
dotp->e_xvalue += ty_nbyte[argtype];
break;
} /*end of the switch on argtype*/
} /*end of the switch on the type*/
} /*end of looping for all arguments*/
return;
PASS2:
/*
* Output the opcode
*/
Outb(opcode);
if ((passno == 2) && liston)
{
byte_out (opcode);
*layoutpos++ = ' ';
}
for (i=0; i<n; i++,ap++) {/* now for the arguments */
argtype=ap->a_atype;
xp=ap->a_xp;
reloc_how = TYPNONE;
if (argtype&AINDX) {
{ Outb(0x40 | ap->a_areg2);
if ((passno == 2) && liston)
byte_out (0x40 | ap->a_areg2); }
argtype &= ~AINDX;
}
if (argtype&ASTAR) {
ap->a_areg1 |= 0x10;
argtype &= ~ASTAR;
}
switch (argtype) {
case AREG: /* %r */
ap->a_areg1 |= 0x50;
break;
case ABASE: /* (%r) */
ap->a_areg1 |= 0x60;
break;
case ADECR: /* -(%r) */
ap->a_areg1 |= 0x70;
break;
case AINCR: /* (%r)+ */
ap->a_areg1 |= 0x80;
break;
case AEXP: /* expr */
argtype = fetcharg(ITABFETCH(opcode), i);
if (argtype == A_BB) {
ap->a_areg1 = argtype =
xp->e_xvalue - (dotp->e_xvalue + 1);
if (xp->e_xtype & XXTRN)
yywarning("%s: destination label is external",
FETCHNAME(ITABFETCH(opcode)));
if (!ISBYTE(argtype) && !jxxxJUMP)
yyerror("%s: Branch too far(%db): try -J flag",
FETCHNAME(ITABFETCH(opcode)),
argtype);
break;
}
if (argtype == A_BW) {
ap->a_areg1 = argtype = xp->e_xvalue
-= dotp->e_xvalue + 2;
if (xp->e_xtype & XXTRN)
yywarning("%s: destination label is external",
FETCHNAME(ITABFETCH(opcode)));
xp->e_xtype = XABS;
if (!ISWORD(argtype) && !jxxxJUMP)
yyerror("%s: Branch too far(%db): try -J flag",
FETCHNAME(ITABFETCH(opcode)),
argtype);
reloc_how = TYPB;
ap->a_areg1 = argtype>>8;
xp->e_xvalue = argtype;
break;
}
/* reduces to expr(pc) mode */
ap->a_areg1 |= (0xAF + mod124[ap->a_dispsize]);
reloc_how = type_124[ap->a_dispsize] + RELOC_PCREL;
break;
case ADISP: /* expr(%r) */
ap->a_areg1 |= 0xA0;
if ((xp->e_xtype&XTYPE)!=XABS || xp->e_xtype&XFORW){
ap->a_areg1 += mod124[ap->a_dispsize];
reloc_how = type_124[ap->a_dispsize];
break;
}
if (xp->e_xvalue==0 && !(ap->a_areg1&0x10)) {
ap->a_areg1 ^= 0xC0;
break;
}
reloc_how = TYPB;
if (ISBYTE(xp->e_xvalue))
break;
ap->a_areg1 += 0x20;
reloc_how = TYPW;
if (ISWORD(xp->e_xvalue))
break;
ap->a_areg1 += 0x20;
reloc_how = TYPL;
break;
case AIMM: /* $expr */
if (ap->a_atype&ASTAR) {
argtype=TYPL;
ap->a_areg1 |= 0x8F;
} else {
argtype = fetcharg(ITABFETCH(opcode), i);
if (argtype&ACCA)
argtype = TYPL;
else
argtype &= TYPMASK;
if ( ( (xp->e_xtype&XTYPE) == XABS)
&& !(xp->e_xtype&XFORW)
&& (argtype != TYPF)
&& (argtype != TYPD)
)
{
if ((xp->e_xvalue <= 63)
&& (xp->e_xvalue >= 0))
{
ap->a_areg1 = xp->e_xvalue;
break;
}
else
if (ISBYTE (xp->e_xvalue))
{
ap->a_areg1 = 0x88;
argtype = TYPB;
}
else
if (ISWORD (xp->e_xvalue))
{
ap->a_areg1 = 0x89;
argtype = TYPW;
}
else
{
ap->a_areg1 = 0x8F;
argtype = TYPL;
}
}
else
{
ap->a_areg1 = 0x8F;
argtype = TYPL;
}
}
reloc_how = argtype;
if (reloc_how == TYPD || reloc_how == TYPF){
if ( ((xp->e_xtype&XTYPE)==XABS)
&& (!(xp->e_xtype&XFORW))
&& (slitflt(xp))
){
reloc_how = TYPNONE;
ap->a_areg1=extlitflt(xp);
}
}
break;
} /*end of the switch on argtype*/
/*
* use the first byte to describe the argument
*/
Outb(ap->a_areg1);
if ((passno == 2) && liston)
byte_out (ap->a_areg1);
if (reloc_how != TYPNONE)
outrel(xp, reloc_how);
if ((passno == 2) && liston)
*layoutpos++ = ' ';
} /*end of the for to pick up all arguments*/
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.