/* i85mch.c

   Copyright (C) 1989-1995 Alan R. Baldwin
   721 Berkeley St., Kent, Ohio 44240

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, 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/>. */

/*
 * 28-Oct-97 Ported from 8085 to 8051 by John Hartman
 */

#include <stdio.h>
#include <setjmp.h>
#include <string.h>
#include "asxxxx.h"
#include "i8051.h"

/*
 * Process machine ops.
 */
VOID
machine(mp)
struct mne *mp;
{
        register unsigned op;
        register int t, t1, v1;
        struct expr e, e1;

        clrexpr(&e);
        clrexpr(&e1);

        op = mp->m_valu;
        switch (mp->m_type) {

        case S_INH:
                outab(op);
                break;

        case S_JMP11:
                /* ACALL or AJMP. In Flat24 mode, this is a
                 * 19 bit destination; in 8051 mode, this is a
                 * 11 bit destination.
                 *
                 * The opcode is merged with the address in a
                 * hack-o-matic fashion by the linker.
                */
                expr(&e, 0);
                if (flat24Mode) {
                        outr19(&e, op, R_J19);
                }
                else {
                        outr11(&e, op, R_J11);
                }
                break;

        case S_JMP16:
                /* LCALL or LJMP. In Flat24 mode, this is a 24 bit
                 * destination; in 8051 mode, this is a 16 bit
                 * destination.
                 */
                expr(&e, 0);
                outab(op);
                if (flat24Mode) {
                        outr24(&e, 0);
                }
                else {
			outrw(&e, R_NORM);
                }
                break;

        case S_ACC:
                t = addr(&e);
                if (t != S_A)
                        aerr();
                outab(op);
                break;

        case S_TYP1:
                /* A, direct, @R0, @R1, R0 to R7.  "INC" also allows DPTR */
                t = addr(&e);

                switch (t) {
                case S_A:
                        outab(op + 4);
                        break;

                case S_DIR:
                case S_EXT:
                        /* Direct is also legal */
                        outab(op + 5);
                        outrb(&e, R_PAG0);
                        break;

                case S_AT_R:
                        outab(op + 6 + e.e_addr);
                        break;

                case S_REG:
                        outab(op + 8 + e.e_addr);
                        break;

                case S_DPTR:
                        if (op != 0)
                                /* only INC (op=0) has DPTR mode */
                                aerr();
                        else
                                outab( 0xA3);
                        break;

                default:
                        aerr();
                }
                break;

        case S_TYP2:
                /* A,#imm; A,direct; A,@R0; A,@R1; A,R0 to A,R7 */
                t = addr(&e);
                if (t != S_A)
                        aerr();
                comma(1);
                t1 = addr(&e1);

                switch (t1) {
                case S_IMMED:
                        outab(op + 4);
			outrb(&e1, R_NORM);
                        break;

                case S_DIR:
                case S_EXT:
                        outab(op + 5);
                        outrb(&e1, R_PAG0);
                        break;

                case S_AT_R:
                        outab(op + 6 + e1.e_addr);
                        break;

                case S_REG:
                        outab(op + 8 + (e1.e_addr));
                        break;

                default:
                        aerr();
                }
                break;

        case S_TYP3:
                /* dir,A; dir,#imm;
                 * A,#imm; A,direct; A,@R0; A,@R1; A,R0 to A,R7
                 * C,direct;  C,/direct
                 */
                t = addr(&e);
                comma(1);
                t1 = addr(&e1);

                switch (t) {
                case S_DIR:
                case S_EXT:
                        switch (t1) {
                        case S_A:
                                outab(op + 2);
                                outrb(&e, R_PAG0);
                                break;

                        case S_IMMED:
                                outab(op + 3);
				outrb(&e, R_PAG0);
				outrb(&e1, R_NORM);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_A:
                        switch (t1) {
                        case S_IMMED:
                                outab(op + 4);
				outrb(&e1, R_NORM);
                                break;

                        case S_DIR:
                        case S_EXT:
                                outab(op + 5);
                                outrb(&e1, R_PAG0);
                                break;

                        case S_AT_R:
                                outab(op + 6 + e1.e_addr);
                                break;

                        case S_REG:
                                outab(op + 8 + e1.e_addr);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_C:
                        /* XRL has no boolean version.  Trap it */
                        if (op == 0x60)
                                aerr();

                        switch (t1) {
                        case S_DIR:
                        case S_EXT:
                                outab(op + 0x32);
                                outrb(&e1, R_PAG0);
                                break;

                        case S_NOT_BIT:
                                outab(op + 0x60);
				outrb(&e1, R_PAG0);
                                break;

                        default:
                                aerr();
                        }
                        break;

                default:
                        aerr();
                }
                break;

        case S_TYP4:
                /* A,direct; A,@R0; A,@R1; A,R0 to A,R7 */
                t = addr(&e);
                if (t != S_A)
                        aerr();
                comma(1);
                t1 = addr(&e1);

                switch (t1) {
                case S_DIR:
                case S_EXT:
                        outab(op + 5);
                        outrb(&e1, R_PAG0);
                        break;

                case S_AT_R:
                        outab(op + 6 + e1.e_addr);
                        break;

                case S_REG:
                        outab(op + 8 + e1.e_addr);
                        break;

                default:
                        aerr();
                }
                break;

        /* MOV instruction, all modes */
        case S_MOV:
                t = addr(&e);
                comma(1);
                t1 = addr(&e1);

                switch (t) {
                case S_A:
                        switch (t1) {
                        case S_IMMED:
                                outab(0x74);
				outrb(&e1, R_NORM);
                                break;

                        case S_DIR:
                        case S_EXT:
                                outab(0xE5);
                                outrb(&e1, R_PAG0);
                                break;

                        case S_AT_R:
                                outab(0xE6 + e1.e_addr);
                                break;

                        case S_REG:
                                outab(0xE8 + e1.e_addr);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_REG:
                        switch (t1) {
                        case S_A:
                                outab(0xF8 + e.e_addr);
                                break;

                        case S_IMMED:
                                outab(0x78 + e.e_addr);
				outrb(&e1, R_NORM);
                                break;

                        case S_DIR:
                        case S_EXT:
                                outab(0xA8 + e.e_addr);
                                outrb(&e1, R_PAG0);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_DIR:
                case S_EXT:
                        switch (t1) {
                        case S_A:
                                outab(0xF5);
                                outrb(&e, R_PAG0);
                                break;

                        case S_IMMED:
                                outab(0x75);
                                outrb(&e, R_PAG0);
				outrb(&e1, R_NORM);
                                break;

                        case S_DIR:
                        case S_EXT:
                                outab(0x85);
                                outrb(&e1, R_PAG0);
                                outrb(&e, R_PAG0);
                                break;

                        case S_AT_R:
                                outab(0x86 + e1.e_addr);
                                outrb(&e, R_PAG0);
                                break;

                        case S_REG:
                                outab(0x88 + e1.e_addr);
                                outrb(&e, R_PAG0);
                                break;

                        case S_C:
                                outab(0x92);
                                outrb(&e, R_PAG0);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_AT_R:
                        switch (t1) {
                        case S_IMMED:
                                outab(0x76 + e.e_addr);
				outrb(&e1, R_NORM);
                                break;

                        case S_DIR:
                        case S_EXT:
                                outab(0xA6 + e.e_addr);
                                outrb(&e1, R_PAG0);
                                break;

                        case S_A:
                                outab(0xF6 + e.e_addr);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_C:
                        if ((t1 != S_DIR) && (t1 != S_EXT))
                                aerr();
                        outab(0xA2);
                        outrb(&e1, R_PAG0);
                        break;

                case S_DPTR:
                        if (t1 != S_IMMED)
                                aerr();
                        outab(0x90);

                        /* mov DPTR, #immed: for Flat24 mode,
                         * #immed is a 24 bit constant. For 8051,
                         * it is a 16 bit constant.
                         */
                        if (flat24Mode) {
                                outr24(&e1, 0);
                        }
                        else {
				outrw(&e1, R_NORM);
                        }
                        break;

                default:
                        aerr();
                }
                break;

        case S_BITBR:
                /* Branch on bit set/clear */
                t = addr(&e);
                if ((t != S_DIR) && (t != S_EXT))
                        aerr();
                /* sdcc svn rev #4994: fixed bug 1865114 */
                comma(1);
                expr(&e1, 0);
                outab(op);
                outrb(&e, R_PAG0);
		if (mchpcr(&e1)) {
 			v1 = (int) (e1.e_addr - dot.s_addr - 1);
                        /* sdcc svn rev #602: Fix some path problems */
                      	if (pass == 2 && ((v1 < -128) || (v1 > 127)))
                                aerr();
                        outab(v1);
                } else {
                        outrb(&e1, R_PCR);
                }
                if (e1.e_mode != S_USER)
                        rerr();
                break;

        case S_BR:
                /* Relative branch */
                /* sdcc svn rev #4994: fixed bug 1865114 */
                expr(&e1, 0);
                outab(op);
		if (mchpcr(&e1)) {
                        v1 = (int) (e1.e_addr - dot.s_addr - 1);
                        /* sdcc svn rev #602: Fix some path problems */
                        if (pass == 2 && ((v1 < -128) || (v1 > 127)))
                                aerr();
                        outab(v1);
                } else {
                        outrb(&e1, R_PCR);
                }
                if (e1.e_mode != S_USER)
                        rerr();
                break;

        case S_CJNE:
                /* A,#;  A,dir;  @R0,#;  @R1,#;  Rn,# */
                t = addr(&e);
                comma(1);
                t1 = addr(&e1);
                switch (t) {
                case S_A:
                        if (t1 == S_IMMED) {
                                outab(op + 4);
				outrb(&e1, R_NORM);
                        }
                        else if ((t1 == S_DIR) || (t1 == S_EXT)) {
                                outab(op + 5);
                                outrb(&e1, R_PAG0);
                        }
                        else
                                aerr();
                break;

                case S_AT_R:
                        outab(op + 6 + e.e_addr);
                        if (t1 != S_IMMED)
                                aerr();
			outrb(&e1, R_NORM);
                        break;

                case S_REG:
                        outab(op + 8 + e.e_addr);
                        if (t1 != S_IMMED)
                                aerr();
			outrb(&e1, R_NORM);
                        break;

                default:
                        aerr();
                }

                /* branch destination */
                comma(1);
		clrexpr(&e1);
		expr(&e1, 0);
		if (mchpcr(&e1)) {
                        v1 = (int) (e1.e_addr - dot.s_addr - 1);
                        /* sdcc svn rev #602: Fix some path problems */
                        if (pass == 2 && ((v1 < -128) || (v1 > 127)))
                                aerr();
                        outab(v1);
                } else {
                        outrb(&e1, R_PCR);
                }
                if (e1.e_mode != S_USER)
                        rerr();
                break;

        case S_DJNZ:
                /* Dir,dest;  Reg,dest */
                t = addr(&e);
                /* sdcc svn rev #4994: fixed bug 1865114 */
                comma(1);
                expr(&e1, 0);
                switch (t) {

                case S_DIR:
                case S_EXT:
                        outab(op + 5);
                        outrb(&e, R_PAG0);
                        break;

                case S_REG:
                        outab(op + 8 + e.e_addr);
                        break;

                default:
                        aerr();
                }

		/* branch destination */
                /* sdcc svn rev #4994: fixed bug 1865114 */
		if (mchpcr(&e1)) {
                        v1 = (int) (e1.e_addr - dot.s_addr - 1);
                        /* sdcc svn rev #602: Fix some path problems */
                        if (pass == 2 && ((v1 < -128) || (v1 > 127)))
                                aerr();
                        outab(v1);
                } else {
                        outrb(&e1, R_PCR);
                }
                if (e1.e_mode != S_USER)
                        rerr();
                break;

        case S_JMP:
                /* @A+DPTR */
                t = addr(&e);
                if (t != S_AT_ADP)
                        aerr();
                outab(op);
                break;

        case S_MOVC:
                /* A,@A+DPTR  A,@A+PC */
                t = addr(&e);
                if (t != S_A)
                        aerr();
                comma(1);
                t1 = addr(&e1);
                if (t1 == S_AT_ADP)
                        outab(0x93);
                else if (t1 == S_AT_APC)
                        outab(0x83);
                else
                        aerr();
                break;

        case S_MOVX:
                /* A,@DPTR  A,@R0  A,@R1  @DPTR,A  @R0,A  @R1,A */
                t = addr(&e);
                comma(1);
                t1 = addr(&e1);

                switch (t) {
                case S_A:
                        switch (t1) {
                        case S_AT_DP:
                                outab(0xE0);
                                break;
                                
                        case S_AT_R:
                                outab(0xE2 + e1.e_addr);
                                break;

                        default:
                                aerr();
                        }
                        break;

                case S_AT_DP:
                        if (t1 == S_A)
                                outab(0xF0);
                        else
                                aerr();
                        break;

                case S_AT_R:
                        if (t1 == S_A)
                                outab(0xF2 + e.e_addr);
                        else
                                aerr();
                        break;

                default:
                        aerr();
                }
                break;

        /* MUL/DIV A,B */
        case S_AB:
                t = addr(&e);
                if (t != S_RAB)
                        aerr();
                outab(op);
                break;

        /* CLR or CPL:  A, C, or bit */
        case S_ACBIT:
                t = addr(&e);
                switch (t) {
                case S_A:
                        if (op == 0xB2)
                                outab(0xF4);
                        else
                                outab(0xE4);
                        break;

                case S_C:
                        outab(op+1);
                        break;

                case S_DIR:
                case S_EXT:
                        outab(op);
                        outrb(&e, R_PAG0);
                        break;

                default:
                        aerr();
                }
                break;

        /* SETB C or bit */
        case S_SETB:
                t = addr(&e);
                switch (t) {
                case S_C:
                        outab(op+1);
                        break;

                case S_DIR:
                case S_EXT:
                        outab(op);
                        outrb(&e, R_PAG0);
                        break;

                default:
                        aerr();
                }
                break;

        /* direct */
        case S_DIRECT:
                t = addr(&e);
                if ((t != S_DIR) && (t != S_EXT)) {
                        aerr();
                        break;
                }
                outab(op);
                outrb(&e, R_PAG0);
                break;

        /* XCHD A,@Rn */
        case S_XCHD:
                t = addr(&e);
                if (t != S_A)
                        aerr();
                comma(1);
                t1 = addr(&e1);
                switch (t1) {
                case S_AT_R:
                        outab(op + e1.e_addr);
                        break;
                default:
                        aerr();
                }
                break;

        default:
                err('o');
        }
}

/*
 * Branch/Jump PCR Mode Check
 */
int
mchpcr(esp)
struct expr *esp;
{
	if (esp->e_base.e_ap == dot.s_area) {
		return(1);
	}
	if (esp->e_flag==0 && esp->e_base.e_ap==NULL) {
		/*
		 * Absolute Destination
		 *
		 * Use the global symbol '.__.ABS.'
		 * of value zero and force the assembler
		 * to use this absolute constant as the
		 * base value for the relocation.
		 */
		esp->e_flag = 1;
		esp->e_base.e_sp = &sym[1];
	}
	return(0);
}

 /*
  * Machine specific initialization
  */

static int beenHere=0;      /* set non-zero if we have done that... */

VOID
minit()
{
        struct sym      *sp;
        struct PreDef   *pd;
	int i;
	char pid[8];
	char *p;

	/*
	 * First time only:
	 *	add the pre-defined symbols to the table
	 *	as local symbols.
	 */
        if (beenHere == 0) {
                pd = preDef;
                while (pd->id) {
			strcpy(pid, pd->id);
			for (i=0; i<2; i++) {
				/*
				 * i == 0,  Create Upper Case Symbols
				 * i == 1,  Create Lower Case Symbols
				 */
				if (i == 1) {
					p = pid;
					while (*p) {
						*p = ccase[*p & 0x007F];
						p++;
					}
				}
                                sp = lookup(pid);
                                if (sp->s_type == S_NEW) {
                                        sp->s_addr = pd->value;
                                        sp->s_type = S_USER;
                                }
                        }
                        pd++;
                }
                beenHere = 1;
        }
}
