diff options
Diffstat (limited to 'target-arm/translate-a64.c')
-rw-r--r-- | target-arm/translate-a64.c | 43 |
1 files changed, 41 insertions, 2 deletions
diff --git a/target-arm/translate-a64.c b/target-arm/translate-a64.c index ead5658d46..b69466585f 100644 --- a/target-arm/translate-a64.c +++ b/target-arm/translate-a64.c @@ -384,10 +384,49 @@ static void disas_exc(DisasContext *s, uint32_t insn) unsupported_encoding(s, insn); } -/* Unconditional branch (register) */ +/* C3.2.7 Unconditional branch (register) + * 31 25 24 21 20 16 15 10 9 5 4 0 + * +---------------+-------+-------+-------+------+-------+ + * | 1 1 0 1 0 1 1 | opc | op2 | op3 | Rn | op4 | + * +---------------+-------+-------+-------+------+-------+ + */ static void disas_uncond_b_reg(DisasContext *s, uint32_t insn) { - unsupported_encoding(s, insn); + unsigned int opc, op2, op3, rn, op4; + + opc = extract32(insn, 21, 4); + op2 = extract32(insn, 16, 5); + op3 = extract32(insn, 10, 6); + rn = extract32(insn, 5, 5); + op4 = extract32(insn, 0, 5); + + if (op4 != 0x0 || op3 != 0x0 || op2 != 0x1f) { + unallocated_encoding(s); + return; + } + + switch (opc) { + case 0: /* BR */ + case 2: /* RET */ + break; + case 1: /* BLR */ + tcg_gen_movi_i64(cpu_reg(s, 30), s->pc); + break; + case 4: /* ERET */ + case 5: /* DRPS */ + if (rn != 0x1f) { + unallocated_encoding(s); + } else { + unsupported_encoding(s, insn); + } + return; + default: + unallocated_encoding(s); + return; + } + + tcg_gen_mov_i64(cpu_pc, cpu_reg(s, rn)); + s->is_jmp = DISAS_JUMP; } /* C3.2 Branches, exception generating and system instructions */ |