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opcodes.c
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opcodes.c
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/****************************************************************************
*
* Process each opcode and pseudo-opcode
* Copyright (C) 2023 Sean Conner
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Comments, questions and criticisms can be sent to: sean@conman.org
*
****************************************************************************/
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <limits.h>
#include <ctype.h>
#include <math.h>
#include "a09.h"
/**************************************************************************/
static unsigned char value_5bit(struct a09 *a09,uint16_t value,int pass)
{
assert(a09 != NULL);
assert((pass == 1) || (pass == 2));
if ((pass == 2) && (value >= 16) && (value <= 65519))
message(a09,MSG_WARNING,"W0003: 16-bit value truncated to 5 bits");
return value & 31;
}
/**************************************************************************/
static unsigned char value_lsb(struct a09 *a09,uint16_t value,int pass)
{
assert(a09 != NULL);
assert((pass == 1) || (pass == 2));
if ((pass == 2) && (value >= 256) && (value <= 65407))
message(a09,MSG_WARNING,"W0004: 16-bit value truncated to 8 bits");
return value & 255;
}
/**************************************************************************/
static bool collect_string(
struct a09 *a09,
struct buffer *restrict wbuf,
struct buffer *restrict rbuf,
char delim
)
{
char c;
assert(a09 != NULL);
assert(wbuf != NULL);
assert(rbuf != NULL);
assert(isgraph(delim));
memset(wbuf->buf,0,sizeof(wbuf->buf));
wbuf->widx = 0;
wbuf->ridx = 0;
while((c = rbuf->buf[rbuf->ridx++]) != delim)
{
if (c == '\0')
return message(a09,MSG_ERROR,"E0013: unexpected end of string");
wbuf->buf[wbuf->widx++] = c;
assert(wbuf->widx < sizeof(wbuf->buf));
}
return true;
}
/**************************************************************************/
bool collect_esc_string(
struct a09 *a09,
struct buffer *restrict wbuf,
struct buffer *restrict rbuf,
char delim
)
{
char c;
assert(a09 != NULL);
assert(wbuf != NULL);
assert(rbuf != NULL);
assert((delim == '"') || (delim == '\''));
memset(wbuf->buf,0,sizeof(wbuf->buf));
wbuf->widx = 0;
wbuf->ridx = 0;
while((c = rbuf->buf[rbuf->ridx++]) != delim)
{
if (c == '\0')
return message(a09,MSG_ERROR,"E0013: unexpected end of string");
if (c == '\\')
{
c = rbuf->buf[rbuf->ridx++];
switch(c)
{
case '"': c = '"'; break;
case '\'': c = '\''; break;
case '\\': c = '\\'; break;
case 'a': c = '\a'; break;
case 'b': c = '\b'; break;
case 'e': c = '\033'; break;
case 'f': c = '\f'; break;
case 'n': c = '\n'; break;
case 'r': c = '\r'; break;
case 't': c = '\t'; break;
case 'v': c = '\v'; break;
case '\0': return message(a09,MSG_ERROR,"E0013: unexpected end of string");
default: return message(a09,MSG_ERROR,"E0014: invalid escape character");
}
}
wbuf->buf[wbuf->widx++] = c;
assert(wbuf->widx < sizeof(wbuf->buf));
}
c = toupper(rbuf->buf[rbuf->ridx]);
switch(c)
{
case 'C':
assert(wbuf->widx < sizeof(wbuf->buf));
if (wbuf->widx > UCHAR_MAX)
return message(a09,MSG_ERROR,"E0071: string too long");
memmove(&wbuf->buf[1],&wbuf->buf[0],wbuf->widx);
wbuf->buf[0] = (char)wbuf->widx;
wbuf->widx++;
rbuf->ridx++;
break;
case 'H':
wbuf->buf[wbuf->widx-1] |= 0x80;
rbuf->ridx++;
break;
case 'Z':
assert(wbuf->widx < sizeof(wbuf->buf));
wbuf->buf[wbuf->widx++] = '\0';
rbuf->ridx++;
break;
default:
break;
}
return true;
}
/**************************************************************************/
bool parse_string(
struct a09 *a09,
struct buffer *restrict wbuf,
struct buffer *restrict rbuf
)
{
assert(a09 != NULL);
assert(wbuf != NULL);
assert(rbuf != NULL);
char c = skip_space(rbuf);
if ((c == '"') || (c == '\''))
return collect_esc_string(a09,wbuf,rbuf,c);
else
return message(a09,MSG_ERROR,"E0015: not a string");
}
/**************************************************************************/
static bool parse_dirext(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->a09 != NULL);
assert(opd->buffer != NULL);
if (!expr(&opd->value,opd->a09,opd->buffer,opd->pass))
return false;
if (opd->value.defined && ((opd->value.value >> 8) == opd->a09->dp))
opd->mode = AM_DIRECT;
else
opd->mode = AM_EXTENDED;
return true;
}
/**************************************************************************/
static unsigned char index_register(char c)
{
switch(toupper(c))
{
case 'X': return 0x00;
case 'Y': return 0x20;
case 'U': return 0x40;
case 'S': return 0x60;
default: abort();
}
}
/**************************************************************************/
static unsigned char acc_register(char c)
{
switch(toupper(c))
{
case 'A': return 0x86;
case 'B': return 0x85;
case 'D': return 0x8B;
default: abort();
}
}
/**************************************************************************/
static bool parse_operand(struct opcdata *opd)
{
assert(opd != NULL);
bool indexindirect = false;
char c = skip_space(opd->buffer);
if ((c == ';') || (c == '\0'))
{
opd->mode = AM_INHERENT;
return true;
}
if (c == '#')
{
if (!expr(&opd->value,opd->a09,opd->buffer,opd->pass))
return false;
c = skip_space(opd->buffer);
if ((c != ';') && (c != '\0'))
{
if (c == ',')
return message(opd->a09,MSG_ERROR,"E0059: syntax error---mixing up immedate and indexed modes?");
else
return message(opd->a09,MSG_ERROR,"E0060: syntax error");
}
opd->mode = AM_IMMED;
return true;
}
if (c == '[')
{
indexindirect = true;
c = skip_space(opd->buffer);
}
if (c == ',')
{
opd->mode = AM_INDEX;
opd->bits = 0;
opd->value.postbyte = 0x80;
c = toupper(skip_space(opd->buffer));
switch(c)
{
case 'X':
case 'Y':
case 'U':
case 'S': opd->value.postbyte |= index_register(c); break;
case '-':
c = opd->buffer->buf[opd->buffer->ridx];
if (c == '-')
{
opd->value.postbyte |= 0x03;
c = opd->buffer->buf[++opd->buffer->ridx];
}
else
opd->value.postbyte |= 0x02;
switch(toupper(c))
{
case 'X':
case 'Y':
case 'U':
case 'S': opd->value.postbyte |= index_register(c); break;
default: return message(opd->a09,MSG_ERROR,"E0016: invalid index register");
}
if (opd->buffer->buf[++opd->buffer->ridx] == ']')
{
if (!indexindirect)
return message(opd->a09,MSG_ERROR,"E0017: end of indirection without start of indirection error");
opd->value.postbyte |= 0x10;
}
return true;
default:
return message(opd->a09,MSG_ERROR,"E0018: invalid index register");
}
c = skip_space(opd->buffer);
if ((c == ';') || (c == '\0') || isspace(c))
{
if (indexindirect)
return message(opd->a09,MSG_ERROR,"E0019: missing end of index indirect mode");
opd->value.postbyte |= 0x04;
return true;
}
else if (c == ']')
{
if (!indexindirect)
return message(opd->a09,MSG_ERROR,"E0017: end of indirection without start of indirection error");
opd->value.postbyte |= 0x14;
return true;
}
else if (c != '+')
return message(opd->a09,MSG_ERROR,"E0020: syntax error in post-increment index mode");
c = opd->buffer->buf[opd->buffer->ridx++];
if (c == '+')
{
opd->value.postbyte |= 0x01;
if (opd->buffer->buf[opd->buffer->ridx++] == ']')
{
if (!indexindirect)
return message(opd->a09,MSG_ERROR,"E0017: end of indirection without start of indirection error");
opd->value.postbyte |= 0x10;
}
return true;
}
else if ((c == ';') || (c == '\0') || isspace(c))
{
if (indexindirect)
return message(opd->a09,MSG_ERROR,"E0019: missing end of index indirect mode");
return true;
}
else
return message(opd->a09,MSG_ERROR,"E0021: syntax error in index mode");
}
opd->buffer->ridx--; // ungetc()
/*------------------------------------------------------------------------
; Special case here, A,r B,r or D,r needs to be checked, if the 2nd next
; character is ',', then we have one-character to check, which could be a
; register. Handle that case here.
;------------------------------------------------------------------------*/
if (opd->buffer->buf[opd->buffer->ridx+1] == ',')
{
opd->mode = AM_INDEX;
opd->bits = 0;
c = toupper(opd->buffer->buf[opd->buffer->ridx]);
switch(c)
{
case 'A':
case 'B':
case 'D':
opd->value.postbyte = acc_register(c);
opd->buffer->ridx += 2; // skip comma
c = toupper(opd->buffer->buf[opd->buffer->ridx]);
switch(c)
{
case 'X':
case 'Y':
case 'U':
case 'S': opd->value.postbyte |= index_register(c); break;
default: return message(opd->a09,MSG_ERROR,"E0018: invalid index register");
}
c = opd->buffer->buf[++opd->buffer->ridx];
if (c == ']')
{
if (!indexindirect)
return message(opd->a09,MSG_ERROR,"E0017: end of indirection without start of indirection error");
opd->value.postbyte |= 0x10;
c = opd->buffer->buf[++opd->buffer->ridx];
}
if ((c == ';') || (c == '\0') || isspace(c))
return true;
return message(opd->a09,MSG_ERROR,"E0022: invalid accumulator register in index mode");
default:
break;
}
}
if (!expr(&opd->value,opd->a09,opd->buffer,opd->pass))
return false;
c = skip_space(opd->buffer);
if ((c == ';') || (c == '\0'))
{
if (indexindirect)
return message(opd->a09,MSG_ERROR,"E0019: missing end of index indirect mode");
if ((opd->value.bits == 5) || (opd->value.bits == 8))
{
opd->mode = AM_DIRECT;
return true;
}
if (opd->value.bits == 16)
{
opd->mode = AM_EXTENDED;
return true;
}
assert(opd->value.bits == 0);
if (opd->value.unknownpass1)
{
opd->mode = AM_EXTENDED;
if (opd->pass == 2)
{
if ((opd->value.value >> 8) == opd->a09->dp)
message(opd->a09,MSG_WARNING,"W0005: address could be 8-bits, maybe use '<'?");
}
return true;
}
if (opd->value.defined && ((opd->value.value >> 8) == opd->a09->dp))
opd->mode = AM_DIRECT;
else
opd->mode = AM_EXTENDED;
return true;
}
if (c == ']')
{
if (!indexindirect)
return message(opd->a09,MSG_ERROR,"E0017: end of indirection without start of indirection error");
opd->value.postbyte = 0x9F;
opd->value.bits = 16;
opd->mode = AM_INDEX;
return true;
}
if (c != ',')
return message(opd->a09,MSG_ERROR,"E0023: missing expected comma");
opd->value.postbyte = 0;
opd->mode = AM_INDEX;
c = skip_space(opd->buffer);
switch(toupper(c))
{
case 'X':
case 'Y':
case 'U':
case 'S':
opd->value.postbyte |= index_register(c);
if (opd->value.bits == 5)
{
if (indexindirect)
{
opd->value.postbyte |= 0x88;
opd->bits = 8;
if (opd->pass == 2)
message(opd->a09,MSG_WARNING,"W0011: 5-bit offset upped to 8 bits for indirect mode");
}
else
{
opd->value.postbyte |= value_5bit(opd->a09,opd->value.value,opd->pass);
opd->bits = 5;
}
}
else if (opd->value.bits == 8)
{
opd->value.postbyte |= 0x88;
opd->bits = 8;
}
else if (opd->value.bits == 16)
{
opd->value.postbyte |= 0x89;
opd->bits = 16;
}
else
{
assert(opd->value.bits == 0);
if (opd->value.unknownpass1)
{
opd->value.postbyte |= 0x89;
opd->bits = 16;
if (opd->pass == 2)
{
if ((opd->value.value < 16) || (opd->value.value > 65519))
{
if (indexindirect)
message(opd->a09,MSG_WARNING,"W0007: offset could be 8-bits, maybe use '<'?");
else
message(opd->a09,MSG_WARNING,"W0006: offset could be 5-bits, maybe use '<<'?");
}
else if ((opd->value.value < 0x80) || (opd->value.value > 0xFF7F))
message(opd->a09,MSG_WARNING,"W0007: offset could be 8-bits, maybe use '<'?");
}
}
else if ((opd->value.value < 16) || (opd->value.value > 65519))
{
/*------------------------------------------------------------
; if the bit size is unspecified, and we have a 0 offset, use
; the ',reg' mode instead of '0,reg'---it's the same size, but
; executes one cycle faster. If you want '0,reg', then use a
; size override on the index.
;-------------------------------------------------------------*/
if (opd->value.value == 0)
{
opd->value.postbyte |= 0x84;
opd->bits = 0;
}
else
{
if (indexindirect)
{
opd->value.postbyte |= 0x88;
opd->bits = 8;
}
else
{
opd->value.postbyte |= opd->value.value & 0x1F;
opd->bits = 5;
}
}
}
else if ((opd->value.value < 0x80) || (opd->value.value > 0xFF7F))
{
opd->value.postbyte |= 0x88;
opd->bits = 8;
}
else
{
opd->value.postbyte |= 0x89;
opd->bits = 16;
}
}
break;
case 'P':
if (toupper(opd->buffer->buf[opd->buffer->ridx]) != 'C')
return message(opd->a09,MSG_ERROR,"E0016: invalid index register");
opd->pcrel = true;
opd->buffer->ridx++;
if (opd->value.bits == 0)
{
uint16_t pc = opd->a09->pc + 2 + (opd->op->page != 0);
uint16_t delta = opd->value.value - pc;
if (opd->value.unknownpass1)
{
opd->value.postbyte = 0x8D;
opd->bits = 16;
if (opd->pass == 2)
{
if ((delta < 0x80) || (delta > 0xFF7F))
message(opd->a09,MSG_WARNING,"W0007: offset could be 8-bits, maybe use '<'?");
}
}
else
{
if ((delta < 0x80) || (delta > 0xFF7F))
{
opd->value.postbyte = 0x8C;
opd->bits = 8;
}
else
{
opd->value.postbyte = 0x8D;
opd->bits = 16;
}
}
}
else if (opd->value.bits == 8)
{
opd->value.postbyte = 0x8C;
opd->bits = 8;
}
else
{
opd->value.postbyte = 0x8D;
opd->bits = 16;
}
break;
default:
return message(opd->a09,MSG_ERROR,"E0016: invalid index register");
}
c = skip_space(opd->buffer);
if (c == ']')
{
if (!indexindirect)
return message(opd->a09,MSG_ERROR,"E0017: end of indirection without start of indirection error");
opd->value.postbyte |= 0x10;
if (opd->bits == 5)
opd->bits = 8;
}
return true;
}
/**************************************************************************/
static bool op_inh(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->sz == 0);
if (!parse_operand(opd))
return false;
if (opd->mode != AM_INHERENT)
return message(opd->a09,MSG_ERROR,"E0024: operands found for op with no operands");
if (opd->op->page)
opd->bytes[opd->sz++] = opd->op->page;
opd->bytes[opd->sz++] = opd->op->opcode;
return true;
}
/**************************************************************************/
static bool finish_index_bytes(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->mode == AM_INDEX);
unsigned char opcode = opd->op->opcode;
if (opcode < 0x30)
opcode += 0x60;
else if (opcode >= 0x80)
opcode += 0x20;
opd->bytes[opd->sz++] = opcode;
opd->bytes[opd->sz++] = opd->value.postbyte;
if (opd->bits == 8)
{
if (opd->pcrel)
{
uint16_t pc = opd->a09->pc + opd->sz + 1;
uint16_t dt = opd->value.value - pc;
opd->value.value = dt;
}
opd->bytes[opd->sz++] = opd->value.value & 255;
}
else if (opd->bits == 16)
{
if (opd->pcrel)
opd->value.value = opd->value.value - (opd->a09->pc + opd->sz + 2);
opd->bytes[opd->sz++] = opd->value.value >> 8;
opd->bytes[opd->sz++] = opd->value.value & 255;
}
return true;
}
/**************************************************************************/
static bool op_idie(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->sz == 0);
assert(opd->a09 != NULL);
assert((opd->pass == 1) || (opd->pass == 2));
if (!parse_operand(opd))
return false;
if (opd->op->page)
opd->bytes[opd->sz++] = opd->op->page;
switch(opd->mode)
{
case AM_IMMED:
opd->bytes[opd->sz++] = opd->op->opcode;
if (opd->op->bit16)
{
opd->bytes[opd->sz++] = opd->value.value >> 8;
opd->bytes[opd->sz++] = opd->value.value & 255;
}
else
opd->bytes[opd->sz++] = value_lsb(opd->a09,opd->value.value,opd->pass);
return true;
case AM_DIRECT:
opd->bytes[opd->sz++] = opd->op->opcode + 0x10;
opd->bytes[opd->sz++] = opd->value.value & 255;
return true;
case AM_INDEX:
return finish_index_bytes(opd);
case AM_EXTENDED:
opd->bytes[opd->sz++] = opd->op->opcode + 0x30;
opd->bytes[opd->sz++] = opd->value.value >> 8;
opd->bytes[opd->sz++] = opd->value.value & 255;
return true;
case AM_INHERENT:
case AM_BRANCH:
return message(opd->a09,MSG_ERROR,"E0025: instruction not inherent");
}
return false;
}
/**************************************************************************/
static bool op_die(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->sz == 0);
assert(opd->a09 != NULL);
assert((opd->pass == 1) || (opd->pass == 2));
if (!parse_operand(opd))
return false;
if (opd->op->page)
opd->bytes[opd->sz++] = opd->op->page;
switch(opd->mode)
{
case AM_IMMED:
return message(opd->a09,MSG_ERROR,"E0026: immediate mode not supported for opcode");
case AM_DIRECT:
opd->bytes[opd->sz++] = opd->op->opcode + ((opd->op->opcode < 0x80) ? 0x00 : 0x10);
opd->bytes[opd->sz++] = opd->value.value & 255;
return true;
case AM_INDEX:
return finish_index_bytes(opd);
case AM_EXTENDED:
opd->bytes[opd->sz++] = opd->op->opcode + ((opd->op->opcode < 0x80) ? 0x70 : 0x30);
opd->bytes[opd->sz++] = opd->value.value >> 8;
opd->bytes[opd->sz++] = opd->value.value & 255;
return true;
case AM_INHERENT:
case AM_BRANCH:
return message(opd->a09,MSG_ERROR,"E0027: Internal error---how did this happen?");
}
return false;
}
/**************************************************************************/
static bool op_imm(struct opcdata *opd)
{
assert(opd != NULL);
if (!parse_operand(opd))
return false;
if (opd->mode != AM_IMMED)
return message(opd->a09,MSG_ERROR,"E0028: instruction only supports immediate mode");
assert(opd->op->page == 0);
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = value_lsb(opd->a09,opd->value.value,opd->pass);
return true;
}
/**************************************************************************/
static bool op_br(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->a09 != NULL);
assert(opd->sz == 0);
assert(opd->op->page == 0);
if (!expr(&opd->value,opd->a09,opd->buffer,opd->pass))
return false;
if (opd->value.external)
{
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = 0;
}
else
{
uint16_t delta = opd->value.value - (opd->a09->pc + 2);
if ((opd->pass == 2) && (opd->op->opcode != 0x21)) /* BRN is exempted */
{
if (delta == 0)
message(opd->a09,MSG_WARNING,"W0012: branch to next location, maybe remove?");
else if ((delta > 0x007F) && (delta < 0xFF80))
return message(opd->a09,MSG_ERROR,"E0029: target exceeds 8-bit range");
}
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = delta & 255;
}
opd->mode = AM_BRANCH;
opd->pcrel = true;
return true;
}
/**************************************************************************/
static bool op_lbr(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->a09 != NULL);
assert(opd->sz == 0);
if (!expr(&opd->value,opd->a09,opd->buffer,opd->pass))
return false;
if (opd->op->page)
opd->bytes[opd->sz++] = opd->op->page;
if (opd->value.external)
{
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = 0;
opd->bytes[opd->sz++] = 0;
}
else
{
uint16_t delta = opd->value.value - (opd->a09->pc + (opd->op->page ? 4 : 3));
if ((opd->pass == 2) && (opd->op->opcode != 0x21))
{
if (delta == 0)
message(opd->a09,MSG_WARNING,"W0012: branch to next location, maybe remove?");
else if ((delta < 0x80) || (delta > 0xFF80))
message(opd->a09,MSG_WARNING,"W0009: offset could be 8-bits, maybe use short branch?");
}
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = delta >> 8;
opd->bytes[opd->sz++] = delta & 255;
}
opd->mode = AM_BRANCH;
opd->pcrel = true;
return true;
}
/**************************************************************************/
static bool op_lea(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->op != NULL);
if (!parse_operand(opd))
return false;
if (opd->mode != AM_INDEX)
return message(opd->a09,MSG_ERROR,"E0030: bad operand");
if (opd->op->page)
opd->bytes[opd->sz++] = opd->op->page;
return finish_index_bytes(opd);
}
/**************************************************************************/
static bool sop_findreg(struct indexregs const **ir,char const *src,char skip)
{
static struct indexregs const index[] =
{
{ "\2PC" , 0x80 , 0x50 , 0x05 , WORD } ,
{ "\1S" , 0x40 , 0x40 , 0x04 , WORD } ,
{ "\1U" , 0x40 , 0x30 , 0x03 , WORD } ,
{ "\1Y" , 0x20 , 0x20 , 0x02 , WORD } ,
{ "\1X" , 0x10 , 0x10 , 0x01 , WORD } ,
{ "\2DP" , 0x08 , 0xB0 , 0x0B , BYTE } ,
{ "\1B" , 0x04 , 0x90 , 0x09 , BYTE } ,
{ "\1A" , 0x02 , 0x80 , 0x08 , BYTE } ,
{ "\2CC" , 0x01 , 0xA0 , 0x0A , BYTE } ,
{ "\1D" , 0x06 , 0x00 , 0x00 , WORD } ,
};
char what[3] = { toupper(src[0]) , toupper(src[1]) , '\0' };
for (size_t i = 0 ; i < sizeof(index) / sizeof(index[0]) ; i++)
{
if (memcmp(what,&index[i].reg[1],index[i].reg[0]) == 0)
{
if (index[i].reg[1] == skip)
return false;
*ir = &index[i];
return true;
}
}
return false;
}
/**************************************************************************/
static bool op_pshpul(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->op != NULL);
assert(opd->op->page == 0);
unsigned char operand = 0;
char skip = tolower(opd->op->name[3]); /* yes, I know! */
char c = skip_space(opd->buffer);
if (c == '\0')
return false;
if (c != '-')
{
opd->buffer->ridx--;
while(!isspace(c) && (c != ';') && (c != '0'))
{
struct indexregs const *reg;
if (!sop_findreg(®,&opd->buffer->buf[opd->buffer->ridx],skip))
return message(opd->a09,MSG_ERROR,"E0031: bad register name for PSH/PUL");
opd->buffer->ridx += reg->reg[0];
operand |= reg->pushpull;
c = skip_space(opd->buffer);
if (c == '\0')
break;
if (c == ';')
break;
if (c != ',')
return message(opd->a09,MSG_ERROR,"E0032: missing comma in register list");
}
}
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = operand;
return true;
}
/**************************************************************************/
static bool op_exg(struct opcdata *opd)
{
assert(opd != NULL);
assert(opd->op != NULL);
assert(opd->op->page == 0);
struct indexregs const *reg1;
struct indexregs const *reg2;
unsigned char operand = 0;
char c = skip_space(opd->buffer);
if (c == '\0')
return false;
opd->buffer->ridx--;
if (!sop_findreg(®1,&opd->buffer->buf[opd->buffer->ridx],'\0'))
return message(opd->a09,MSG_ERROR,"E0033: bad register name for EXG/TFR");
opd->buffer->ridx += reg1->reg[0];
operand |= reg1->tehi;
if (opd->buffer->buf[opd->buffer->ridx] != ',')
return message(opd->a09,MSG_ERROR,"E0034: missing comma");
opd->buffer->ridx++;
if (!sop_findreg(®2,&opd->buffer->buf[opd->buffer->ridx],'\0'))
return message(opd->a09,MSG_ERROR,"E0033: bad register name for EXG/TFR");
if ((opd->pass == 1) && (reg1->bit16 != reg2->bit16))
message(opd->a09,MSG_WARNING,"W0008: ext/tfr mixed sized registers");
operand |= reg2->telo;
opd->bytes[opd->sz++] = opd->op->opcode;
opd->bytes[opd->sz++] = operand;
return true;
}
/**************************************************************************/