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// license:BSD-3-Clause
// copyright-holders:Patrick Mackinlay
#include "emu.h"
#include "rompdasm.h"
#define R2 ((op >> 4) & 15)
#define R3 (op & 15)
#define R3_0(i, r3) (r3 ? util::string_format("0x%x(%s)", i, gpr[r3]) : util::string_format("0x%x", i))
// repurpose reserved bit for invalid condition
#define N (BIT(op, 7) ? R2 : 13)
static char const *const gpr[16] =
{
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
};
static char const *const scr[16] =
{
"scr0", "scr1", "scr2", "scr3", "scr4", "scr5", "cous", "cou",
"ts", "scr9", "mq", "mpcs", "irb", "iar", "ics", "cs",
};
static char const *const cc[16] =
{
"", "ge", "ne", "le", "nc", "?", "no", "ntb",
"nop", "lt", "eq", "gt", "c", "?", "o", "tb",
};
static char const *const tc[8] =
{
"nop", "igt", "ieq", "ige", "ile", "ine", "ile", "rap"
};
offs_t romp_disassembler::disassemble(std::ostream &stream, offs_t pc, data_buffer const &opcodes, data_buffer const ¶ms)
{
u16 const op = opcodes.r16(pc);
unsigned bytes = 2;
u32 flags = 0;
switch (op >> 12)
{
// JI format
case 0x0: util::stream_format(stream, "j%-4s 0x%x", cc[(op >> 8) & 15], pc + (s32(s8(op)) << 1)); break; // jump on [not] condition bit
// DS format
case 0x1: util::stream_format(stream, "stcs %s,%s", gpr[R2], R3_0((op >> 8) & 15, R3)); break; // store character short
case 0x2: util::stream_format(stream, "sths %s,%s", gpr[R2], R3_0((op >> 7) & 30, R3)); break; // store half short
case 0x3: util::stream_format(stream, "sts %s,%s", gpr[R2], R3_0((op >> 6) & 60, R3)); break; // store short
case 0x4: util::stream_format(stream, "lcs %s,%s", gpr[R2], R3_0((op >> 8) & 15, R3)); break; // load character short
case 0x5: util::stream_format(stream, "lhas %s,%s", gpr[R2], R3_0((op >> 7) & 30, R3)); break; // load half algebraic short
case 0x6: // compute address short (X format)
if (R3)
util::stream_format(stream, "cas %s,%s,%s", gpr[(op >> 8) & 15], gpr[R2], gpr[R3]);
else
util::stream_format(stream, "cas %s,%s", gpr[(op >> 8) & 15], gpr[R2]);
break;
case 0x7: util::stream_format(stream, "ls %s,%s", gpr[R2], R3_0((op >> 6) & 60, R3)); break; // load short
case 0x8:
// BI, BA format
{
u32 const b = opcodes.r32(pc);
bytes = 4;
switch (op >> 8)
{
// 80-87
case 0x88: util::stream_format(stream, "b%-4s 0x%x", cc[N - 8], pc + (s32(b << 12) >> 11)); break; // branch on not condition bit immediate
case 0x89: util::stream_format(stream, "b%-4s 0x%x", util::string_format("%sx", cc[N - 8]), pc + (s32(b << 12) >> 11)); break; // branch on not condition bit immediate with execute
case 0x8a: util::stream_format(stream, "bala 0x%x", b & 0x00fffffeU); flags |= STEP_OVER; break; // branch and link absolute
case 0x8b: util::stream_format(stream, "balax 0x%x", b & 0x00fffffeU); flags |= STEP_OVER | step_over_extra(1); break; // branch and link absolute with execute
case 0x8c: util::stream_format(stream, "bali %s,0x%x", gpr[R2], pc + (s32(b << 12) >> 11)); flags |= STEP_OVER; break; // branch and link immediate
case 0x8d: util::stream_format(stream, "balix %s,0x%x", gpr[R2], pc + (s32(b << 12) >> 11)); flags |= STEP_OVER | step_over_extra(1); break; // branch and link immediate with execute
case 0x8e: util::stream_format(stream, "b%-4s 0x%x", cc[N], pc + (s32(b << 12) >> 11)); break; // branch on condition bit immediate
case 0x8f: util::stream_format(stream, "b%-4s 0x%x", util::string_format("%sx", cc[N]), pc + (s32(b << 12) >> 11)); break; // branch on condition bit immediate with execute
}
}
break;
case 0xc:
case 0xd:
// D format
{
u16 const i = opcodes.r16(pc + 2);
bytes = 4;
switch (op >> 8)
{
case 0xc0: util::stream_format(stream, "svc %s", R3_0(i, R3)); flags |= STEP_OVER; break; // supervisor call
case 0xc1: util::stream_format(stream, "ai %s,%s,0x%x", gpr[R2], gpr[R3], s16(i)); break; // add immediate
case 0xc2: util::stream_format(stream, "cal16 %s,%s", gpr[R2], R3_0(i, R3)); break; // compute address lower half 16-bit
case 0xc3: util::stream_format(stream, "oiu %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // or immediate upper half
case 0xc4: util::stream_format(stream, "oil %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // or immediate lower half
case 0xc5: util::stream_format(stream, "nilz %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // and immediate lower half extended zeroes
case 0xc6: util::stream_format(stream, "nilo %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // and immediate lower half extended ones
case 0xc7: util::stream_format(stream, "xil %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // exclusive or immediate lower half
case 0xc8: util::stream_format(stream, "cal %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // compute address lower half
case 0xc9: util::stream_format(stream, "lm %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // load multiple
case 0xca: util::stream_format(stream, "lha %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // load half algebraic
case 0xcb: util::stream_format(stream, "ior %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // input/output read
case 0xcc: util::stream_format(stream, "t%-4s %s,0x%x", tc[R2 & 7], gpr[R3], s16(i)); break; // trap on condition immediate
case 0xcd: util::stream_format(stream, "l %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // load
case 0xce: util::stream_format(stream, "lc %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // load character
case 0xcf: util::stream_format(stream, "tsh %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // test and set half
case 0xd0: util::stream_format(stream, "lps %d,%s", R2, R3_0(s16(i), R3)); flags |= STEP_OUT; break; // load program status
case 0xd1: util::stream_format(stream, "aei %s,%s,0x%x", gpr[R2], gpr[R3], s16(i)); break; // add extended immediate
case 0xd2: util::stream_format(stream, "sfi %s,%s,0x%x", gpr[R2], gpr[R3], s16(i)); break; // subtract from immediate
case 0xd3: util::stream_format(stream, "cli %s,0x%x", gpr[R3], s16(i)); break; // compare logical immediate
case 0xd4: util::stream_format(stream, "ci %s,0x%x", gpr[R3], s16(i)); break; // compare immediate
case 0xd5: util::stream_format(stream, "niuz %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // and immediate upper half extended zeroes
case 0xd6: util::stream_format(stream, "niuo %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // and immediate upper half extended ones
case 0xd7: util::stream_format(stream, "xiu %s,%s,0x%x", gpr[R2], gpr[R3], i); break; // exclusive or immediate upper half
case 0xd8: util::stream_format(stream, "cau %s,%s", gpr[R2], R3_0(i, R3)); break; // compute address upper half
case 0xd9: util::stream_format(stream, "stm %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // store multiple
case 0xda: util::stream_format(stream, "lh %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // load half
case 0xdb: util::stream_format(stream, "iow %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // input/output write
case 0xdc: util::stream_format(stream, "sth %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // store half
case 0xdd: util::stream_format(stream, "st %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // store
case 0xde: util::stream_format(stream, "stc %s,%s", gpr[R2], R3_0(s16(i), R3)); break; // store character
// df
}
}
break;
case 0x9:
case 0xa:
case 0xb:
case 0xe:
case 0xf:
// R format
switch (op >> 8)
{
case 0x90: util::stream_format(stream, "ais %s,%d", gpr[R2], R3); break; // add immediate short
case 0x91: util::stream_format(stream, "inc %s,%d", gpr[R2], R3); break; // increment
case 0x92: util::stream_format(stream, "sis %s,%d", gpr[R2], R3); break; // subtract immediate short
case 0x93: util::stream_format(stream, "dec %s,%d", gpr[R2], R3); break; // decrement
case 0x94: util::stream_format(stream, "cis %s,%d", gpr[R2], R3); break; // compare immediate short
case 0x95: util::stream_format(stream, "clrsb %s,%d", scr[R2], R3); break; // clear scr bit
case 0x96: util::stream_format(stream, "mfs %s,%s", scr[R2], gpr[R3]); break; // move from scr
case 0x97: util::stream_format(stream, "setsb %s,%d", scr[R2], R3); break; // set scr bit
case 0x98: util::stream_format(stream, "clrb %s,%d", gpr[R2], R3); break; // clear bit upper half
case 0x99: util::stream_format(stream, "clrb %s,%d", gpr[R2], R3 + 16); break; // clear bit lower half
case 0x9a: util::stream_format(stream, "setb %s,%d", gpr[R2], R3); break; // set bit upper half
case 0x9b: util::stream_format(stream, "setb %s,%d", gpr[R2], R3 + 16); break; // set bit lower half
case 0x9c: util::stream_format(stream, "mftbi %s,%d", gpr[R2], R3); break; // move from test bit immediate upper half
case 0x9d: util::stream_format(stream, "mftbi %s,%d", gpr[R2], R3 + 16); break; // move from test bit immediate lower half
case 0x9e: util::stream_format(stream, "mttbi %s,%d", gpr[R2], R3); break; // move to test bit immediate upper half
case 0x9f: util::stream_format(stream, "mttbi %s,%d", gpr[R2], R3 + 16); break; // move to test bit immediate lower half
case 0xa0: util::stream_format(stream, "sari %s,%d", gpr[R2], R3); break; // shift algebraic right immediate
case 0xa1: util::stream_format(stream, "sari %s,%d", gpr[R2], R3 + 16); break; // shift algebraic right immediate plus sixteen
// a2, a3
case 0xa4: util::stream_format(stream, "lis %s,%d", gpr[R2], R3); break; // load immediate short
// a5, a6, a7
case 0xa8: util::stream_format(stream, "sri %s,%d", gpr[R2], R3); break; // shift right immediate
case 0xa9: util::stream_format(stream, "sri %s,%d", gpr[R2], R3 + 16); break; // shift right immediate plus sixteen
case 0xaa: util::stream_format(stream, "sli %s,%d", gpr[R2], R3); break; // shift left immediate
case 0xab: util::stream_format(stream, "sli %s,%d", gpr[R2], R3 + 16); break; // shift left immediate plus sixteen
case 0xac: util::stream_format(stream, "srpi %s,%d", gpr[R2], R3); break; // shift right paired immediate
case 0xad: util::stream_format(stream, "srpi %s,%d", gpr[R2], R3 + 16); break; // shift right paired immediate plus sixteen
case 0xae: util::stream_format(stream, "slpi %s,%d", gpr[R2], R3); break; // shift left paired immediate
case 0xaf: util::stream_format(stream, "slpi %s,%d", gpr[R2], R3 + 16); break; // shift left paired immediate plus sixteen
case 0xb0: util::stream_format(stream, "sar %s,%s", gpr[R2], gpr[R3]); break; // shift algebraic right
case 0xb1: util::stream_format(stream, "exts %s,%s", gpr[R2], gpr[R3]); break; // extend sign
case 0xb2: util::stream_format(stream, "sf %s,%s", gpr[R2], gpr[R3]); break; // subtract from
case 0xb3: util::stream_format(stream, "cl %s,%s", gpr[R2], gpr[R3]); break; // compare logical
case 0xb4: util::stream_format(stream, "c %s,%s", gpr[R2], gpr[R3]); break; // compare
case 0xb5: util::stream_format(stream, "mts %s,%s", scr[R2], gpr[R3]); break; // move to scr
case 0xb6: util::stream_format(stream, "d %s,%s", gpr[R2], gpr[R3]); break; // divide step
// b7
case 0xb8: util::stream_format(stream, "sr %s,%s", gpr[R2], gpr[R3]); break; // shift right
case 0xb9: util::stream_format(stream, "srp %s,%s", gpr[R2], gpr[R3]); break; // shift right paired
case 0xba: util::stream_format(stream, "sl %s,%s", gpr[R2], gpr[R3]); break; // shift left
case 0xbb: util::stream_format(stream, "slp %s,%s", gpr[R2], gpr[R3]); break; // shift left paired
case 0xbc: util::stream_format(stream, "mftb %s,%s", gpr[R2], gpr[R3]); break; // move from test bit
case 0xbd: util::stream_format(stream, "tgte %s,%s", gpr[R2], gpr[R3]); break; // trap if register greater than or equal
case 0xbe: util::stream_format(stream, "tlt %s,%s", gpr[R2], gpr[R3]); break; // trap if register less than
case 0xbf: util::stream_format(stream, "mttb %s,%s", gpr[R2], gpr[R3]); break; // move to test bit
case 0xe0: util::stream_format(stream, "abs %s,%s", gpr[R2], gpr[R3]); break; // absolute
case 0xe1: util::stream_format(stream, "a %s,%s", gpr[R2], gpr[R3]); break; // add
case 0xe2: util::stream_format(stream, "s %s,%s", gpr[R2], gpr[R3]); break; // subtract
case 0xe3: util::stream_format(stream, "o %s,%s", gpr[R2], gpr[R3]); break; // or
case 0xe4: util::stream_format(stream, "twoc %s,%s", gpr[R2], gpr[R3]); break; // twos complement
case 0xe5: util::stream_format(stream, "n %s,%s", gpr[R2], gpr[R3]); break; // and
case 0xe6: util::stream_format(stream, "m %s,%s", gpr[R2], gpr[R3]); break; // multiply step
case 0xe7: util::stream_format(stream, "x %s,%s", gpr[R2], gpr[R3]); break; // exclusive or
case 0xe8: util::stream_format(stream, "b%-5s %s", util::string_format("%sr", cc[N - 8]), gpr[R3]); break; // branch on not condition bit
case 0xe9: util::stream_format(stream, "b%-5s %s", util::string_format("%srx", cc[N - 8]), gpr[R3]); break; // branch on not condition bit with execute
// ea
case 0xeb: util::stream_format(stream, "lhs %s,0(%s)", gpr[R2], gpr[R3]); break; // load half short
case 0xec: util::stream_format(stream, "balr %s,%s", gpr[R2], gpr[R3]); flags |= STEP_OVER; break; // branch and link
case 0xed: util::stream_format(stream, "balrx %s,%s", gpr[R2], gpr[R3]); flags |= STEP_OVER | step_over_extra(1); break; // branch and link with execute
case 0xee: util::stream_format(stream, "b%-5s %s", util::string_format("%sr", cc[N]), gpr[R3]); break; // branch on condition bit
case 0xef: util::stream_format(stream, "b%-5s %s", util::string_format("%srx", cc[N]), gpr[R3]); break; // branch on condition bit with execute
case 0xf0: util::stream_format(stream, "wait"); break; // wait
case 0xf1: util::stream_format(stream, "ae %s,%s", gpr[R2], gpr[R3]); break; // add extended
case 0xf2: util::stream_format(stream, "se %s,%s", gpr[R2], gpr[R3]); break; // subtract extended
case 0xf3: util::stream_format(stream, "ca16 %s,%s", gpr[R2], gpr[R3]); break; // compute address 16-bit
case 0xf4: util::stream_format(stream, "onec %s,%s", gpr[R2], gpr[R3]); break; // ones complement
case 0xf5: util::stream_format(stream, "clz %s,%s", gpr[R2], gpr[R3]); break; // count leading zeros
// f6, f7, f8
case 0xf9: util::stream_format(stream, "mc03 %s,%s", gpr[R2], gpr[R3]); break; // move character zero from three
case 0xfa: util::stream_format(stream, "mc13 %s,%s", gpr[R2], gpr[R3]); break; // move character one from three
case 0xfb: util::stream_format(stream, "mc23 %s,%s", gpr[R2], gpr[R3]); break; // move character two from three
case 0xfc: util::stream_format(stream, "mc33 %s,%s", gpr[R2], gpr[R3]); break; // move character three from three
case 0xfd: util::stream_format(stream, "mc30 %s,%s", gpr[R2], gpr[R3]); break; // move character three from zero
case 0xfe: util::stream_format(stream, "mc31 %s,%s", gpr[R2], gpr[R3]); break; // move character three from one
case 0xff: util::stream_format(stream, "mc32 %s,%s", gpr[R2], gpr[R3]); break; // move character three from two
}
break;
}
return bytes | flags | SUPPORTED;
}
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