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move src/instr.h to include/instr.h because it will be needed by assembler for code generation.

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Henrik Hautakoski 2018-11-01 14:57:10 +01:00
parent 817642b7e4
commit cf752ab682
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5 changed files with 32 additions and 7 deletions
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src/instr_decode.c Normal file
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/* instr_decode.c
*
* Copyright (C) 2012,2014 Henrik Hautakoski <henrik.hautakoski@gmail.com>
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#include "instr_decode.h"
void instr_decode(unsigned char *instr, struct instr *out) {
out->opcode = *instr >> 4;
if (out->opcode == OP_NOOP)
return;
// J-Type
if (out->opcode == OP_JMP) {
out->j.addr = ((*instr & 0xF) << 8) + *(instr + 1);
// if MSB (bit 12) is set
// perform 2s complement by setting bit 13-16 to 1
/*
if (out->j.addr & 0x0800)
out->j.addr |= 0xF000; */
} else {
out->r.rs = *instr & 0xF;
// I-Type
if (out->opcode == OP_MOVL || out->opcode == OP_MOVH || out->opcode == OP_INT) {
out->i.imm = *(instr + 1);
}
// R/RI-Type
else {
out->r.r0 = *(instr + 1) >> 4;
out->r.r1 = *(instr + 1) & 0xF;
}
}
}