diff options
Diffstat (limited to 'src/sim/id.cc')
| -rw-r--r-- | src/sim/id.cc | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/src/sim/id.cc b/src/sim/id.cc index 0b75b64..0c0be91 100644 --- a/src/sim/id.cc +++ b/src/sim/id.cc @@ -48,11 +48,11 @@ void ID::advance_helper() Mnemonic m; Type t; - // it may be good to ensure we are not doing - // work that has already been done - if (this->curr_instr && this->curr_instr->get_mnemonic() == NONE) { + if (curr_instr->get_mnemonic() == NOP) + this->status = OK; + else { s1 = curr_instr->get_instr_bits(); - get_instr_fields(s1, s2, s3, m ,t); + get_instr_fields(s1, s2, s3, m, t); if (this->status == OK) { curr_instr->set_s1(s1); curr_instr->set_s2(s2); @@ -63,7 +63,8 @@ void ID::advance_helper() } } -void ID::get_instr_fields(signed int &s1, signed int &s2, signed int &s3, Mnemonic &m, Type &t) +void ID::get_instr_fields( + signed int &s1, signed int &s2, signed int &s3, Mnemonic &m, Type &t) { unsigned int type; this->split_instr(s1, type, m); @@ -75,11 +76,11 @@ void ID::get_instr_fields(signed int &s1, signed int &s2, signed int &s3, Mnemon break; case 0b01: t = I; - this->decode_I_type(s1, s2, s3); + this->decode_I_type(s1, s2, s3, m); break; case 0b10: t = J; - this->decode_J_type(s1, s2); + this->decode_J_type(s1, s2, s3); break; case 0b11: t = INV; @@ -101,14 +102,17 @@ void ID::decode_R_type(signed int &s1, signed int &s2, signed int &s3) r1 = this->read_guard(s1); r2 = this->read_guard(s2); - this->write_guard(s3); - this->status = (r1 == OK && r2 == OK) ? OK : STALLED; + + if (this->status == OK) + this->write_guard(s3); } -void ID::decode_I_type(signed int &s1, signed int &s2, signed int &s3) +void ID::decode_I_type( + signed int &s1, signed int &s2, signed int &s3, Mnemonic &m) { unsigned int s0b, s1b, s2b; + Response r1; s0b = REG_SIZE; s1b = s0b + REG_SIZE; @@ -117,16 +121,22 @@ void ID::decode_I_type(signed int &s1, signed int &s2, signed int &s3) s2 = GET_MID_BITS(s1, s0b, s1b); s1 = GET_LS_BITS(s1, s0b); - this->status = this->read_guard(s1); - this->write_guard(s2); + r1 = this->read_guard(s1); + if (m != STORE && m != STOREV) { + this->status = r1; + if (r1 == OK) + this->write_guard(s2); + } else + this->status = (this->read_guard(s2) == OK && r1 == OK) ? OK : STALLED; } -void ID::decode_J_type(signed int &s1, signed int &s2) +void ID::decode_J_type(signed int &s1, signed int &s2, signed int &s3) { unsigned int s0b, s1b; s0b = REG_SIZE; s1b = WORD_SPEC; + s3 = 0; s2 = GET_MID_BITS(s1, s0b, s1b); s1 = GET_LS_BITS(s1, s0b); |