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[/] [System09/] [trunk/] [Tools/] [as09/] [do09.c] - Blame information for rev 95

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/*
 *      MC6809 specific processing
 */
 
#define PAGE2 0x10
#define PAGE3 0x11
#define IPBYTE 0x9F /* extended indirect postbyte */
#define SWI     0x3F
 
/* register names */
 
#define RD 0
#define RX 1
#define RY 2
#define RU 3
#define RS 4
#define RPC 5
#define RA 8
#define RB 9
#define RCC 10
#define RDP 11
#define RPCR 12
 
/* convert tfr/exg reg number into psh/pul format */
int     regs[] = { 6,16,32,64,64,128,0,0,2,4,1,8,0};
int     rcycl[]= { 2,2, 2, 2, 2, 2,  0,0,1,1,1,1,0};
 
/* addressing modes */
#define IMMED   0       /* immediate */
#define IND     1       /* indexed */
#define INDIR   2       /* indirect */
#define OTHER   3       /* NOTA */
 
/*
 *      localinit --- machine specific initialization
 */
localinit()
{
}
 
/*
 *      do_op --- process mnemonic
 *
 * Called with the base opcode and it's class. Optr points to
 * the beginning of the operand field.
 */
void do_op(int opcode,int class)
{
 int     dist;   /* relative branch distance */
 int     src,dst;/* source and destination registers */
 int     pbyte;  /* postbyte value */
 int     amode;  /* indicated addressing mode */
 int j;
 
 amode = set_mode();     /* pickup indicated addressing mode */
 
 switch(class){
  case INH:                       /* inherent addressing */
   emit(opcode);
   return;
  case GEN:                       /* general addressing */
   do_gen(opcode,amode);
   return;
  case IMM:                       /* immediate addressing */
   if( amode != IMMED ){
    error("Immediate Operand Required");
    return;
    }
   Optr++;
   eval();
   emit(opcode);
   emit(lobyte(Result));
   return;
  case REL:                       /* short relative branches */
   eval();
   dist = Result - (Pc+2);
   emit(opcode);
   if( (dist >127 || dist <-128) && Pass==2){
    error("Branch out of Range");
    emit(lobyte(-2));
    return;
    }
   emit(lobyte(dist));
   return;
  case P2REL:                     /* long relative branches */
   eval();
   dist = Result - (Pc+4);
   emit(PAGE2);
   emit(opcode);
   eword(dist);
   return;
  case P1REL:                     /* lbra and lbsr */
   if( amode == IMMED)
    Optr++; /* kludge for C compiler */
   eval();
   dist = Result - (Pc+3);
   emit(opcode);
   eword(dist);
   return;
  case NOIMM:
   if( amode == IMMED ){
    error("Immediate Addressing Illegal");
    return;
    }
   do_gen(opcode,amode);
   return;
  case P2GEN:
   emit(PAGE2);
   if( amode == IMMED ){
    emit(opcode);
    Optr++;
    eval();
    eword(Result);
    return;
    }
   do_gen(opcode,amode);
   return;
  case P3GEN:
   emit(PAGE3);
   if( amode == IMMED ){
    emit(opcode);
    Optr++;
    eval();
    eword(Result);
    return;
    }
   do_gen(opcode,amode);
   return;
  case RTOR:                      /* tfr and exg */
   emit(opcode);
   src = regnum();
   while(alpha(*Optr))Optr++;
   if(src==ERR){
    error("Register Name Required");
    emit(0);
    return;
    }
   if(*Optr++ != ','){
    error("Missing ,");
    emit(0);
    return;
    }
   dst = regnum();
   while(alpha(*Optr))Optr++;
   if(dst==ERR){
    error("Register Name Required");
    emit(0);
    return;
    }
   if( src==RPCR || dst==RPCR){
    error("PCR illegal here");
    emit(0);
    return;
    }
   if( (src <=5 && dst >=8) ||
       (src >=8 && dst <=5)){
    error("Register Size Mismatch");
    emit(0);
    return;
    }
   emit( (src<<4)+dst );
   return;
  case INDEXED:                   /* indexed addressing only */
   if( *Optr == '#'){
    Optr++;         /* kludge city */
    amode = IND;
    }
   if( amode != IND ){
    error("Indexed Addressing Required");
    return;
    }
   do_indexed(opcode);
   return;
  case RLIST:                     /* pushes and pulls */
   if(*Operand == EOS){
    error("Register List Required");
    return;
    }
   emit(opcode);
   pbyte = 0;
   do{
    j = regnum();
    if( j == ERR || j==RPCR)
     error("Illegal Register Name");
    else if(j==RS && (opcode==52))
     error("Can't Push S on S");
    else if(j==RU && (opcode==54))
     error("Can't Push U on U");
    else if(j==RS && (opcode==53))
     error("Can't Pull S from S");
    else if(j==RU && (opcode==55))
     error("Can't Pull U from U");
    else{
     pbyte |= regs[j];
     Cycles += rcycl[j];
     }
    while(*Optr != EOS && alpha(*Optr))Optr++;
   }while( *Optr++ == ',' );
   emit(lobyte(pbyte));
   return;
  case P2NOIMM:
   if( amode == IMMED )
    error("Immediate Addressing Illegal");
   else{
    emit(PAGE2);
    do_gen(opcode,amode);
    }
   return;
  case P2INH:                     /* Page 2 inherent */
   emit(PAGE2);
   emit(opcode);
   return;
  case P3INH:                     /* Page 3 inherent */
   emit(PAGE3);
   emit(opcode);
   return;
  case LONGIMM:
   if( amode == IMMED ){
    emit(opcode);
    Optr++;
    eval();
    eword(Result);
    }
   else
    do_gen(opcode,amode);
   return;
  case GRP2:
   if( amode == IND ){
    do_indexed(opcode+0x60);
    return;
    }
   else if( amode == INDIR){
    Optr++;
    emit(opcode + 0x60);
    emit(IPBYTE);
    eval();
    eword(Result);
    Cycles += 7;
    if(*Optr == ']'){
     Optr++;
     return;
     }
    error("Missing ']'");
    return;
    }
   eval();
   if(Force_word){
    emit(opcode+0x70);
    eword(Result);
    Cycles += 3;
    return;
    }
   if(Force_byte){
    emit(opcode);
    emit(lobyte(Result));
    Cycles += 2;
    return;
    }
   if(Result>=0 && Result <=0xFF){
    emit(opcode);
    emit(lobyte(Result));
    Cycles += 2;
    return;
    }
   else {
    emit(opcode+0x70);
    eword(Result);
    Cycles += 3;
    return;
    }
  case SYS:                       /* system call */
   emit(SWI);
   eval();
   emit(lobyte(Result));
   return;
  default:
   fatal("Error in Mnemonic table");
  }
}
 
 
/*
 *      do_gen --- process general addressing mode stuff
 */
do_gen(op,mode)
int     op;
int     mode;
{
 if( mode == IMMED){
  Optr++;
  emit(op);
  eval();
  emit(lobyte(Result));
        return(0);
  }
 else if( mode == IND ){
  do_indexed(op+0x20);
        return(0);
  }
 else if( mode == INDIR){
  Optr++;
  emit(op+0x20);
  emit(IPBYTE);
  eval();
  eword(Result);
  Cycles += 7;
  if(*Optr == ']'){
   Optr++;
         return(0);
   }
  error("Missing ']'");
        return(0);
  }
 else if( mode == OTHER){
  eval();
  if(Force_word){
   emit(op+0x30);
   eword(Result);
   Cycles += 3;
         return(0);
   }
  if(Force_byte){
   emit(op+0x10);
   emit(lobyte(Result));
   Cycles += 2;
         return(0);
   }
  if(Result>=0 && Result <=0xFF){
   emit(op+0x10);
   emit(lobyte(Result));
   Cycles += 2;
         return(0);
   }
  else {
   emit(op+0x30);
   eword(Result);
   Cycles += 3;
         return(0);
   }
  }
 else {
  error("Unknown Addressing Mode");
        return(0);
  }
}
 
/*
 *      do_indexed --- handle all wierd stuff for indexed addressing
 */
do_indexed(op)
int op;
{
 int     pbyte;
 int     j,k;
 int     predec,pstinc;
 
 Cycles += 2;    /* indexed is always 2+ base cycle count */
 predec=0;
 pstinc=0;
 pbyte=128;
 emit(op);
 if(*Optr=='['){
  pbyte |= 0x10;    /* set indirect bit */
  Optr++;
  if( !any((char)']',Optr))
   error("Missing ']'");
  Cycles += 3;    /* indirection takes this much longer */
  }
 j=regnum();
 if(j==RA){
  Cycles++;
  abd_index(pbyte+6);
        return(0);
  }
 if(j==RB){
  Cycles++;
  abd_index(pbyte+5);
        return(0);
  }
 if(j==RD){
  Cycles += 4;
  abd_index(pbyte+11);
        return(0);
  }
 eval();
 Optr++;
 while(*Optr=='-'){
  predec++;
  Optr++;
  }
 j=regnum();
 while( alpha(*Optr) )Optr++;
 while(*Optr=='+'){
  pstinc++;
  Optr++;
  }
 if(j==RPC || j==RPCR){
  if( pstinc || predec ){
   error("Auto Inc/Dec Illegal on PC");
         return(0);
   }
  if(j==RPC){
   if(Force_word){
    emit(pbyte+13);
    eword(Result);
    Cycles += 5;
                return(0);
    }
   if(Force_byte){
    emit(pbyte+12);
    emit(lobyte(Result));
    Cycles++;
                return(0);
    }
   if(Result>=-128 && Result <=127){
    emit(pbyte+12);
    emit(lobyte(Result));
    Cycles++;
                return(0);
    }
   else {
    emit(pbyte+13);
    eword(Result);
    Cycles += 5;
                return(0);
    }
   }
  /* PCR addressing */
  if(Force_word){
   emit(pbyte+13);
   eword(Result-(Pc+2));
   Cycles += 5;
         return(0);
   }
  if(Force_byte){
   emit(pbyte+12);
   emit(lobyte(Result-(Pc+1)));
   Cycles++;
         return(0);
   }
  k=Result-(Pc+2);
  if( k >= -128 && k <= 127){
   emit(pbyte+12);
   emit(lobyte(Result-(Pc+1)));
   Cycles++;
         return(0);
   }
  else{
   emit(pbyte+13);
   eword(Result-(Pc+2));
   Cycles += 5;
         return(0);
   }
  }
 if(predec || pstinc){
  if(Result != 0){
   error("Offset must be Zero");
         return(0);
   }
  if(predec>2 || pstinc>2){
   error("Auto Inc/Dec by 1 or 2 only");
         return(0);
   }
  if((predec==1 && (pbyte&0x10) != 0) ||
     (pstinc==1 && (pbyte&0x10) != 0)){
   error("No Auto Inc/Dec by 1 for Indirect");
         return(0);
   }
  if(predec && pstinc){
   error("Can't do both!");
         return(0);
   }
  if(predec)
   pbyte += predec+1;
  if(pstinc)
   pbyte += pstinc-1;
  pbyte += rtype(j);
  emit(pbyte);
  Cycles += 1 + predec + pstinc;
        return(0);
  }
 pbyte += rtype(j);
 if(Force_word){
  emit(pbyte+0x09);
  eword(Result);
  Cycles += 4;
        return(0);
  }
 if(Force_byte){
  emit(pbyte+0x08);
  emit(lobyte(Result));
  Cycles++;
        return(0);
  }
 if(Result==0){
  emit(pbyte+0x04);
        return(0);
  }
 if((Result >= -16) && (Result <= 15) && ((pbyte&16)==0)){
  pbyte &= 127;
  pbyte += Result&31;
  emit(pbyte);
  Cycles++;
        return(0);
  }
 if(Result >= -128 && Result <= 127){
  emit(pbyte+0x08);
  emit(lobyte(Result));
  Cycles++;
        return(0);
  }
 emit(pbyte+0x09);
 eword(Result);
 Cycles += 4;
 return(0);
}
 
 
/*
 *      abd_index --- a,b or d indexed
 */
 
abd_index(pbyte)
int pbyte;
{
 int     k;
 
 Optr += 2;
 k=regnum();
 pbyte += rtype(k);
 emit(pbyte);
 return(0);
}
 
/*
 *      rtype --- return register type in post-byte format
 */
rtype(r)
int r;
{
 switch(r){
 case RX:        return(0x00);
 case RY:        return(0x20);
 case RU:        return(0x40);
 case RS:        return(0x60);
  }
 error("Illegal Register for Indexed");
 return(0);
}
 
/*
 *      set_mode --- determine addressing mode from operand field
 */
set_mode()
{
 register char *p;
 
 if( *Operand == '#' )
  return(IMMED);          /* immediate addressing */
 p = Operand;
 while( *p != EOS && *p != BLANK && *p != TAB){/* any , before break */
  if( *p == ',')
   return(IND);    /* indexed addressing */
  p++;
  }
 if( *Operand == '[')
  return(INDIR);          /* indirect addressing */
 return(OTHER);                  /* NOTA */
}
 
/*
 *      regnum --- return register number of *Optr
 */
regnum()
{
 if( head(Optr,"D" ))return(RD);
 if( head(Optr,"d" ))return(RD);
 if( head(Optr,"X" ))return(RX);
 if( head(Optr,"x" ))return(RX);
 if( head(Optr,"Y" ))return(RY);
 if( head(Optr,"y" ))return(RY);
 if( head(Optr,"U" ))return(RU);
 if( head(Optr,"u" ))return(RU);
 if( head(Optr,"S" ))return(RS);
 if( head(Optr,"s" ))return(RS);
 if( head(Optr,"PC" ))return(RPC);
 if( head(Optr,"pc" ))return(RPC);
 if( head(Optr,"PCR" ))return(RPCR);
 if( head(Optr,"pcr" ))return(RPCR);
 if( head(Optr,"A" ))return(RA);
 if( head(Optr,"a" ))return(RA);
 if( head(Optr,"B" ))return(RB);
 if( head(Optr,"b" ))return(RB);
 if( head(Optr,"CC" ))return(RCC);
 if( head(Optr,"cc" ))return(RCC);
 if( head(Optr,"DP" ))return(RDP);
 if( head(Optr,"dp" ))return(RDP);
 return(ERR);
}
 
 

Line No.	Rev	Author	Line
1	83	davidgb	`/*`
2			`* MC6809 specific processing`
3			`*/`
4
5			`#define PAGE2 0x10`
6			`#define PAGE3 0x11`
7			`#define IPBYTE 0x9F /* extended indirect postbyte */`
8			`#define SWI 0x3F`
9
10			`/* register names */`
11
12			`#define RD 0`
13			`#define RX 1`
14			`#define RY 2`
15			`#define RU 3`
16			`#define RS 4`
17			`#define RPC 5`
18			`#define RA 8`
19			`#define RB 9`
20			`#define RCC 10`
21			`#define RDP 11`
22			`#define RPCR 12`
23
24			`/* convert tfr/exg reg number into psh/pul format */`
25			`int regs[] = { 6,16,32,64,64,128,0,0,2,4,1,8,0};`
26			`int rcycl[]= { 2,2, 2, 2, 2, 2, 0,0,1,1,1,1,0};`
27
28			`/* addressing modes */`
29			`#define IMMED 0 /* immediate */`
30			`#define IND 1 /* indexed */`
31			`#define INDIR 2 /* indirect */`
32			`#define OTHER 3 /* NOTA */`
33
34			`/*`
35			`* localinit --- machine specific initialization`
36			`*/`
37			`localinit()`
38			`{`
39			`}`
40
41			`/*`
42			`* do_op --- process mnemonic`
43			`*`
44			`* Called with the base opcode and it's class. Optr points to`
45			`* the beginning of the operand field.`
46			`*/`
47			`void do_op(int opcode,int class)`
48			`{`
49			`int dist; /* relative branch distance */`
50			`int src,dst;/* source and destination registers */`
51			`int pbyte; /* postbyte value */`
52			`int amode; /* indicated addressing mode */`
53			`int j;`
54
55			`amode = set_mode(); /* pickup indicated addressing mode */`
56
57			`switch(class){`
58			`case INH: /* inherent addressing */`
59			`emit(opcode);`
60			`return;`
61			`case GEN: /* general addressing */`
62			`do_gen(opcode,amode);`
63			`return;`
64			`case IMM: /* immediate addressing */`
65			`if( amode != IMMED ){`
66			`error("Immediate Operand Required");`
67			`return;`
68			`}`
69			`Optr++;`
70			`eval();`
71			`emit(opcode);`
72			`emit(lobyte(Result));`
73			`return;`
74			`case REL: /* short relative branches */`
75			`eval();`
76			`dist = Result - (Pc+2);`
77			`emit(opcode);`
78			`if( (dist >127 \|\| dist <-128) && Pass==2){`
79			`error("Branch out of Range");`
80			`emit(lobyte(-2));`
81			`return;`
82			`}`
83			`emit(lobyte(dist));`
84			`return;`
85			`case P2REL: /* long relative branches */`
86			`eval();`
87			`dist = Result - (Pc+4);`
88			`emit(PAGE2);`
89			`emit(opcode);`
90			`eword(dist);`
91			`return;`
92			`case P1REL: /* lbra and lbsr */`
93			`if( amode == IMMED)`
94			`Optr++; /* kludge for C compiler */`
95			`eval();`
96			`dist = Result - (Pc+3);`
97			`emit(opcode);`
98			`eword(dist);`
99			`return;`
100			`case NOIMM:`
101			`if( amode == IMMED ){`
102			`error("Immediate Addressing Illegal");`
103			`return;`
104			`}`
105			`do_gen(opcode,amode);`
106			`return;`
107			`case P2GEN:`
108			`emit(PAGE2);`
109			`if( amode == IMMED ){`
110			`emit(opcode);`
111			`Optr++;`
112			`eval();`
113			`eword(Result);`
114			`return;`
115			`}`
116			`do_gen(opcode,amode);`
117			`return;`
118			`case P3GEN:`
119			`emit(PAGE3);`
120			`if( amode == IMMED ){`
121			`emit(opcode);`
122			`Optr++;`
123			`eval();`
124			`eword(Result);`
125			`return;`
126			`}`
127			`do_gen(opcode,amode);`
128			`return;`
129			`case RTOR: /* tfr and exg */`
130			`emit(opcode);`
131			`src = regnum();`
132			`while(alpha(*Optr))Optr++;`
133			`if(src==ERR){`
134			`error("Register Name Required");`
135			`emit(0);`
136			`return;`
137			`}`
138			`if(*Optr++ != ','){`
139			`error("Missing ,");`
140			`emit(0);`
141			`return;`
142			`}`
143			`dst = regnum();`
144			`while(alpha(*Optr))Optr++;`
145			`if(dst==ERR){`
146			`error("Register Name Required");`
147			`emit(0);`
148			`return;`
149			`}`
150			`if( src==RPCR \|\| dst==RPCR){`
151			`error("PCR illegal here");`
152			`emit(0);`
153			`return;`
154			`}`
155			`if( (src <=5 && dst >=8) \|\|`
156			`(src >=8 && dst <=5)){`
157			`error("Register Size Mismatch");`
158			`emit(0);`
159			`return;`
160			`}`
161			`emit( (src<<4)+dst );`
162			`return;`
163			`case INDEXED: /* indexed addressing only */`
164			`if( *Optr == '#'){`
165			`Optr++; /* kludge city */`
166			`amode = IND;`
167			`}`
168			`if( amode != IND ){`
169			`error("Indexed Addressing Required");`
170			`return;`
171			`}`
172			`do_indexed(opcode);`
173			`return;`
174			`case RLIST: /* pushes and pulls */`
175			`if(*Operand == EOS){`
176			`error("Register List Required");`
177			`return;`
178			`}`
179			`emit(opcode);`
180			`pbyte = 0;`
181			`do{`
182			`j = regnum();`
183			`if( j == ERR \|\| j==RPCR)`
184			`error("Illegal Register Name");`
185			`else if(j==RS && (opcode==52))`
186			`error("Can't Push S on S");`
187			`else if(j==RU && (opcode==54))`
188			`error("Can't Push U on U");`
189			`else if(j==RS && (opcode==53))`
190			`error("Can't Pull S from S");`
191			`else if(j==RU && (opcode==55))`
192			`error("Can't Pull U from U");`
193			`else{`
194			`pbyte \|= regs[j];`
195			`Cycles += rcycl[j];`
196			`}`
197			`while(Optr != EOS && alpha(Optr))Optr++;`
198			`}while( *Optr++ == ',' );`
199			`emit(lobyte(pbyte));`
200			`return;`
201			`case P2NOIMM:`
202			`if( amode == IMMED )`
203			`error("Immediate Addressing Illegal");`
204			`else{`
205			`emit(PAGE2);`
206			`do_gen(opcode,amode);`
207			`}`
208			`return;`
209			`case P2INH: /* Page 2 inherent */`
210			`emit(PAGE2);`
211			`emit(opcode);`
212			`return;`
213			`case P3INH: /* Page 3 inherent */`
214			`emit(PAGE3);`
215			`emit(opcode);`
216			`return;`
217			`case LONGIMM:`
218			`if( amode == IMMED ){`
219			`emit(opcode);`
220			`Optr++;`
221			`eval();`
222			`eword(Result);`
223			`}`
224			`else`
225			`do_gen(opcode,amode);`
226			`return;`
227			`case GRP2:`
228			`if( amode == IND ){`
229			`do_indexed(opcode+0x60);`
230			`return;`
231			`}`
232			`else if( amode == INDIR){`
233			`Optr++;`
234			`emit(opcode + 0x60);`
235			`emit(IPBYTE);`
236			`eval();`
237			`eword(Result);`
238			`Cycles += 7;`
239			`if(*Optr == ']'){`
240			`Optr++;`
241			`return;`
242			`}`
243			`error("Missing ']'");`
244			`return;`
245			`}`
246			`eval();`
247			`if(Force_word){`
248			`emit(opcode+0x70);`
249			`eword(Result);`
250			`Cycles += 3;`
251			`return;`
252			`}`
253			`if(Force_byte){`
254			`emit(opcode);`
255			`emit(lobyte(Result));`
256			`Cycles += 2;`
257			`return;`
258			`}`
259			`if(Result>=0 && Result <=0xFF){`
260			`emit(opcode);`
261			`emit(lobyte(Result));`
262			`Cycles += 2;`
263			`return;`
264			`}`
265			`else {`
266			`emit(opcode+0x70);`
267			`eword(Result);`
268			`Cycles += 3;`
269			`return;`
270			`}`
271			`case SYS: /* system call */`
272			`emit(SWI);`
273			`eval();`
274			`emit(lobyte(Result));`
275			`return;`
276			`default:`
277			`fatal("Error in Mnemonic table");`
278			`}`
279			`}`
280
281
282			`/*`
283			`* do_gen --- process general addressing mode stuff`
284			`*/`
285			`do_gen(op,mode)`
286			`int op;`
287			`int mode;`
288			`{`
289			`if( mode == IMMED){`
290			`Optr++;`
291			`emit(op);`
292			`eval();`
293			`emit(lobyte(Result));`
294			`return(0);`
295			`}`
296			`else if( mode == IND ){`
297			`do_indexed(op+0x20);`
298			`return(0);`
299			`}`
300			`else if( mode == INDIR){`
301			`Optr++;`
302			`emit(op+0x20);`
303			`emit(IPBYTE);`
304			`eval();`
305			`eword(Result);`
306			`Cycles += 7;`
307			`if(*Optr == ']'){`
308			`Optr++;`
309			`return(0);`
310			`}`
311			`error("Missing ']'");`
312			`return(0);`
313			`}`
314			`else if( mode == OTHER){`
315			`eval();`
316			`if(Force_word){`
317			`emit(op+0x30);`
318			`eword(Result);`
319			`Cycles += 3;`
320			`return(0);`
321			`}`
322			`if(Force_byte){`
323			`emit(op+0x10);`
324			`emit(lobyte(Result));`
325			`Cycles += 2;`
326			`return(0);`
327			`}`
328			`if(Result>=0 && Result <=0xFF){`
329			`emit(op+0x10);`
330			`emit(lobyte(Result));`
331			`Cycles += 2;`
332			`return(0);`
333			`}`
334			`else {`
335			`emit(op+0x30);`
336			`eword(Result);`
337			`Cycles += 3;`
338			`return(0);`
339			`}`
340			`}`
341			`else {`
342			`error("Unknown Addressing Mode");`
343			`return(0);`
344			`}`
345			`}`
346
347			`/*`
348			`* do_indexed --- handle all wierd stuff for indexed addressing`
349			`*/`
350			`do_indexed(op)`
351			`int op;`
352			`{`
353			`int pbyte;`
354			`int j,k;`
355			`int predec,pstinc;`
356
357			`Cycles += 2; /* indexed is always 2+ base cycle count */`
358			`predec=0;`
359			`pstinc=0;`
360			`pbyte=128;`
361			`emit(op);`
362			`if(*Optr=='['){`
363			`pbyte \|= 0x10; /* set indirect bit */`
364			`Optr++;`
365			`if( !any((char)']',Optr))`
366			`error("Missing ']'");`
367			`Cycles += 3; /* indirection takes this much longer */`
368			`}`
369			`j=regnum();`
370			`if(j==RA){`
371			`Cycles++;`
372			`abd_index(pbyte+6);`
373			`return(0);`
374			`}`
375			`if(j==RB){`
376			`Cycles++;`
377			`abd_index(pbyte+5);`
378			`return(0);`
379			`}`
380			`if(j==RD){`
381			`Cycles += 4;`
382			`abd_index(pbyte+11);`
383			`return(0);`
384			`}`
385			`eval();`
386			`Optr++;`
387			`while(*Optr=='-'){`
388			`predec++;`
389			`Optr++;`
390			`}`
391			`j=regnum();`
392			`while( alpha(*Optr) )Optr++;`
393			`while(*Optr=='+'){`
394			`pstinc++;`
395			`Optr++;`
396			`}`
397			`if(j==RPC \|\| j==RPCR){`
398			`if( pstinc \|\| predec ){`
399			`error("Auto Inc/Dec Illegal on PC");`
400			`return(0);`
401			`}`
402			`if(j==RPC){`
403			`if(Force_word){`
404			`emit(pbyte+13);`
405			`eword(Result);`
406			`Cycles += 5;`
407			`return(0);`
408			`}`
409			`if(Force_byte){`
410			`emit(pbyte+12);`
411			`emit(lobyte(Result));`
412			`Cycles++;`
413			`return(0);`
414			`}`
415			`if(Result>=-128 && Result <=127){`
416			`emit(pbyte+12);`
417			`emit(lobyte(Result));`
418			`Cycles++;`
419			`return(0);`
420			`}`
421			`else {`
422			`emit(pbyte+13);`
423			`eword(Result);`
424			`Cycles += 5;`
425			`return(0);`
426			`}`
427			`}`
428			`/* PCR addressing */`
429			`if(Force_word){`
430			`emit(pbyte+13);`
431			`eword(Result-(Pc+2));`
432			`Cycles += 5;`
433			`return(0);`
434			`}`
435			`if(Force_byte){`
436			`emit(pbyte+12);`
437			`emit(lobyte(Result-(Pc+1)));`
438			`Cycles++;`
439			`return(0);`
440			`}`
441			`k=Result-(Pc+2);`
442			`if( k >= -128 && k <= 127){`
443			`emit(pbyte+12);`
444			`emit(lobyte(Result-(Pc+1)));`
445			`Cycles++;`
446			`return(0);`
447			`}`
448			`else{`
449			`emit(pbyte+13);`
450			`eword(Result-(Pc+2));`
451			`Cycles += 5;`
452			`return(0);`
453			`}`
454			`}`
455			`if(predec \|\| pstinc){`
456			`if(Result != 0){`
457			`error("Offset must be Zero");`
458			`return(0);`
459			`}`
460			`if(predec>2 \|\| pstinc>2){`
461			`error("Auto Inc/Dec by 1 or 2 only");`
462			`return(0);`
463			`}`
464			`if((predec==1 && (pbyte&0x10) != 0) \|\|`
465			`(pstinc==1 && (pbyte&0x10) != 0)){`
466			`error("No Auto Inc/Dec by 1 for Indirect");`
467			`return(0);`
468			`}`
469			`if(predec && pstinc){`
470			`error("Can't do both!");`
471			`return(0);`
472			`}`
473			`if(predec)`
474			`pbyte += predec+1;`
475			`if(pstinc)`
476			`pbyte += pstinc-1;`
477			`pbyte += rtype(j);`
478			`emit(pbyte);`
479			`Cycles += 1 + predec + pstinc;`
480			`return(0);`
481			`}`
482			`pbyte += rtype(j);`
483			`if(Force_word){`
484			`emit(pbyte+0x09);`
485			`eword(Result);`
486			`Cycles += 4;`
487			`return(0);`
488			`}`
489			`if(Force_byte){`
490			`emit(pbyte+0x08);`
491			`emit(lobyte(Result));`
492			`Cycles++;`
493			`return(0);`
494			`}`
495			`if(Result==0){`
496			`emit(pbyte+0x04);`
497			`return(0);`
498			`}`
499			`if((Result >= -16) && (Result <= 15) && ((pbyte&16)==0)){`
500			`pbyte &= 127;`
501			`pbyte += Result&31;`
502			`emit(pbyte);`
503			`Cycles++;`
504			`return(0);`
505			`}`
506			`if(Result >= -128 && Result <= 127){`
507			`emit(pbyte+0x08);`
508			`emit(lobyte(Result));`
509			`Cycles++;`
510			`return(0);`
511			`}`
512			`emit(pbyte+0x09);`
513			`eword(Result);`
514			`Cycles += 4;`
515			`return(0);`
516			`}`
517
518
519			`/*`
520			`* abd_index --- a,b or d indexed`
521			`*/`
522
523			`abd_index(pbyte)`
524			`int pbyte;`
525			`{`
526			`int k;`
527
528			`Optr += 2;`
529			`k=regnum();`
530			`pbyte += rtype(k);`
531			`emit(pbyte);`
532			`return(0);`
533			`}`
534
535			`/*`
536			`* rtype --- return register type in post-byte format`
537			`*/`
538			`rtype(r)`
539			`int r;`
540			`{`
541			`switch(r){`
542			`case RX: return(0x00);`
543			`case RY: return(0x20);`
544			`case RU: return(0x40);`
545			`case RS: return(0x60);`
546			`}`
547			`error("Illegal Register for Indexed");`
548			`return(0);`
549			`}`
550
551			`/*`
552			`* set_mode --- determine addressing mode from operand field`
553			`*/`
554			`set_mode()`
555			`{`
556			`register char *p;`
557
558			`if( *Operand == '#' )`
559			`return(IMMED); /* immediate addressing */`
560			`p = Operand;`
561			`while( p != EOS && p != BLANK && p != TAB){/ any , before break */`
562			`if( *p == ',')`
563			`return(IND); /* indexed addressing */`
564			`p++;`
565			`}`
566			`if( *Operand == '[')`
567			`return(INDIR); /* indirect addressing */`
568			`return(OTHER); /* NOTA */`
569			`}`
570
571			`/*`
572			`* regnum --- return register number of *Optr`
573			`*/`
574			`regnum()`
575			`{`
576			`if( head(Optr,"D" ))return(RD);`
577			`if( head(Optr,"d" ))return(RD);`
578			`if( head(Optr,"X" ))return(RX);`
579			`if( head(Optr,"x" ))return(RX);`
580			`if( head(Optr,"Y" ))return(RY);`
581			`if( head(Optr,"y" ))return(RY);`
582			`if( head(Optr,"U" ))return(RU);`
583			`if( head(Optr,"u" ))return(RU);`
584			`if( head(Optr,"S" ))return(RS);`
585			`if( head(Optr,"s" ))return(RS);`
586			`if( head(Optr,"PC" ))return(RPC);`
587			`if( head(Optr,"pc" ))return(RPC);`
588			`if( head(Optr,"PCR" ))return(RPCR);`
589			`if( head(Optr,"pcr" ))return(RPCR);`
590			`if( head(Optr,"A" ))return(RA);`
591			`if( head(Optr,"a" ))return(RA);`
592			`if( head(Optr,"B" ))return(RB);`
593			`if( head(Optr,"b" ))return(RB);`
594			`if( head(Optr,"CC" ))return(RCC);`
595			`if( head(Optr,"cc" ))return(RCC);`
596			`if( head(Optr,"DP" ))return(RDP);`
597			`if( head(Optr,"dp" ))return(RDP);`
598			`return(ERR);`
599			`}`
600
601

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