From 8612d99d36269d5f6ed76a38ea5469031d236dca Mon Sep 17 00:00:00 2001 From: folkert van heusden Date: Fri, 25 Mar 2022 22:35:26 +0100 Subject: [PATCH] code clean-up --- cpu.cpp | 121 ++++++++++++++++++++++---------------------------------- cpu.h | 2 + 2 files changed, 50 insertions(+), 73 deletions(-) diff --git a/cpu.cpp b/cpu.cpp index a37dfa0..3fb8aca 100644 --- a/cpu.cpp +++ b/cpu.cpp @@ -85,6 +85,14 @@ void cpu::setRegisterLowByte(const int nr, const bool word_mode, const uint16_t } } +void cpu::put_result(const uint16_t a, const uint8_t dst_mode, const uint8_t dst_reg, const bool word_mode, const uint16_t value) +{ + if (dst_mode == 0) + setRegisterLowByte(dst_reg, word_mode, value); + else + b->write(a, word_mode, value); +} + void cpu::addRegister(const int nr, const bool prev_mode, const uint16_t value) { if (nr < 6) @@ -338,14 +346,14 @@ bool cpu::double_operand_instructions(const uint16_t instr) const uint8_t src_mode = (src >> 3) & 7; const uint8_t src_reg = src & 7; + uint16_t src_value = operation == 0b110 ? 0 : getGAM(src_mode, src_reg, word_mode, false); + const uint8_t dst = instr & 63; const uint8_t dst_mode = (dst >> 3) & 7; const uint8_t dst_reg = dst & 7; switch(operation) { case 0b001: { // MOV/MOVB Move Word/Byte - uint16_t src_value = getGAM(src_mode, src_reg, word_mode, false); - if (word_mode && dst_mode == 0) setRegister(dst_reg, false, int8_t(src_value)); // int8_t: sign extension else @@ -359,7 +367,6 @@ bool cpu::double_operand_instructions(const uint16_t instr) } case 0b010: { // CMP/CMPB Compare Word/Byte - uint16_t src_value = getGAM(src_mode, src_reg, word_mode, false); uint16_t dst_value = getGAM(dst_mode, dst_reg, word_mode, false); uint16_t temp = (src_value - dst_value) & (word_mode ? 0xff : 0xffff); @@ -373,7 +380,6 @@ bool cpu::double_operand_instructions(const uint16_t instr) } case 0b011: { // BIT/BITB Bit Test Word/Byte - uint16_t src_value = getGAM(src_mode, src_reg, word_mode, false); uint16_t dst_value = getGAM(dst_mode, dst_reg, word_mode, false); uint16_t result = (dst_value & src_value) & (word_mode ? 0xff : 0xffff); @@ -385,15 +391,11 @@ bool cpu::double_operand_instructions(const uint16_t instr) } case 0b100: { // BIC/BICB Bit Clear Word/Byte - uint16_t src_value = getGAM(src_mode, src_reg, word_mode, false); - uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); + uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); - uint16_t result = b->read(a, word_mode) & ~src_value; + uint16_t result = b->read(a, word_mode) & ~src_value; - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, result); - else - b -> write(a, word_mode, result); + put_result(a, dst_mode, dst_reg, word_mode, result); setPSW_n(SIGN(result, word_mode)); setPSW_z(result == 0); @@ -403,15 +405,11 @@ bool cpu::double_operand_instructions(const uint16_t instr) } case 0b101: { // BIS/BISB Bit Set Word/Byte - uint16_t src_value = getGAM(src_mode, src_reg, word_mode, false); - uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); + uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); - uint16_t result = b->read(a, word_mode) | src_value; + uint16_t result = b->read(a, word_mode) | src_value; - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, result); - else - b -> write(a, word_mode, result); + put_result(a, dst_mode, dst_reg, word_mode, result); setPSW_n(SIGN(result, word_mode)); setPSW_z(result == 0); @@ -421,7 +419,8 @@ bool cpu::double_operand_instructions(const uint16_t instr) } case 0b110: { // ADD/SUB Add/Subtract Word - int16_t src_value = getGAM(src_mode, src_reg, false, false); + src_value = getGAM(src_mode, src_reg, false, false); + uint16_t dst_addr = getGAMAddress(dst_mode, dst_reg, false, false); int16_t dst_value = b->readWord(dst_addr); int16_t result = 0; @@ -690,10 +689,7 @@ bool cpu::single_operand_instructions(const uint16_t instr) setPSW_v(false); setPSW_c(true); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, v); - else - b -> write(a, word_mode, v); + put_result(a, dst_mode, dst_reg, word_mode, v); break; } @@ -702,13 +698,13 @@ bool cpu::single_operand_instructions(const uint16_t instr) uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); uint16_t v = b -> read(a, word_mode); int32_t vl = (v + 1) & (word_mode ? 0xff : 0xffff); + setPSW_n(word_mode ? vl > 127 : vl > 32767); setPSW_z(vl == 0); setPSW_v(word_mode ? v == 0x7f : v == 0x7fff); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, vl); - else - b -> write(a, word_mode, vl); + + put_result(a, dst_mode, dst_reg, word_mode, vl); + break; } @@ -721,10 +717,8 @@ bool cpu::single_operand_instructions(const uint16_t instr) setPSW_z(vl == 0); setPSW_v(word_mode ? v == 0x80 : v == 0x8000); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, vl); - else - b -> write(a, word_mode, vl); + put_result(a, dst_mode, dst_reg, word_mode, vl); + break; } @@ -732,10 +726,9 @@ bool cpu::single_operand_instructions(const uint16_t instr) uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); uint16_t v = b -> read(a, word_mode); int32_t vl = word_mode ? uint8_t(-int8_t(v)) : -int16_t(v); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, vl); - else - b -> write(a, word_mode, vl); + + put_result(a, dst_mode, dst_reg, word_mode, vl); + setPSW_n(SIGN(vl, word_mode)); setPSW_z(vl == 0); setPSW_v(word_mode ? vl == 0x80 : vl == 0x8000); @@ -748,10 +741,7 @@ bool cpu::single_operand_instructions(const uint16_t instr) uint16_t org = b -> read(a, word_mode); uint16_t new_ = org + getPSW_c(); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, new_); - else - b -> write(a, word_mode, new_); + put_result(a, dst_mode, dst_reg, word_mode, new_); setPSW_n(SIGN(new_, word_mode)); setPSW_z(new_ == 0); @@ -765,10 +755,7 @@ bool cpu::single_operand_instructions(const uint16_t instr) uint16_t v = b -> read(a, word_mode); int32_t vl = (v - getPSW_c()) & (word_mode ? 0xff : 0xffff); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, vl); - else - b -> write(a, word_mode, vl); + put_result(a, dst_mode, dst_reg, word_mode, vl); setPSW_n(SIGN(vl, word_mode)); setPSW_z(vl == 0); @@ -783,10 +770,12 @@ bool cpu::single_operand_instructions(const uint16_t instr) case 0b000101111: { // TST/TSTB uint16_t v = getGAM(dst_mode, dst_reg, word_mode, false); + setPSW_n(SIGN(v, word_mode)); setPSW_z(v == 0); setPSW_v(false); setPSW_c(false); + break; } @@ -798,21 +787,16 @@ bool cpu::single_operand_instructions(const uint16_t instr) uint16_t temp = 0; if (word_mode) { temp = (t >> 1) | (getPSW_c() << 7); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, temp); - else - b -> writeByte(a, temp); + + put_result(a, dst_mode, dst_reg, word_mode, temp); } else { temp = (t >> 1) | (getPSW_c() << 15); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, temp); - else - b -> writeWord(a, temp); + + put_result(a, dst_mode, dst_reg, word_mode, temp); } setPSW_c(new_carry); - setPSW_n(SIGN(temp, word_mode)); setPSW_z(temp == 0); setPSW_v(getPSW_c() ^ getPSW_n()); @@ -829,22 +813,17 @@ bool cpu::single_operand_instructions(const uint16_t instr) if (word_mode) { new_carry = t & 0x80; temp = ((t << 1) | getPSW_c()) & 0xff; - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, temp); - else - b -> writeByte(a, temp); + + put_result(a, dst_mode, dst_reg, word_mode, temp); } else { new_carry = t & 0x8000; temp = (t << 1) | getPSW_c(); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, temp); - else - b -> writeWord(a, temp); + + put_result(a, dst_mode, dst_reg, word_mode, temp); } setPSW_c(new_carry); - setPSW_n(SIGN(temp, word_mode)); setPSW_z(temp == 0); setPSW_v(getPSW_c() ^ getPSW_n()); @@ -860,19 +839,18 @@ bool cpu::single_operand_instructions(const uint16_t instr) setPSW_c(vl & 1); vl >>= 1; + if (word_mode) vl |= hb << 7; else vl |= hb << 15; - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, vl); - else - b -> write(a, word_mode, vl); + put_result(a, dst_mode, dst_reg, word_mode, vl); setPSW_n(SIGN(vl, word_mode)); setPSW_z(vl == 0); setPSW_v(getPSW_n() ^ getPSW_c()); + break; } @@ -880,14 +858,14 @@ bool cpu::single_operand_instructions(const uint16_t instr) uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false); int32_t vl = b -> read(a, word_mode); uint16_t v = (vl << 1) & (word_mode ? 0xff : 0xffff); + setPSW_n(word_mode ? v & 0x80 : v & 0x8000); setPSW_z(v == 0); setPSW_c(word_mode ? vl & 0x80 : vl & 0x8000); setPSW_v(getPSW_n() ^ getPSW_c()); - if (dst_mode == 0) - setRegisterLowByte(dst_reg, word_mode, v); - else - b -> write(a, word_mode, v); + + put_result(a, dst_mode, dst_reg, word_mode, v); + break; } @@ -955,10 +933,7 @@ bool cpu::single_operand_instructions(const uint16_t instr) setPSW_z(getPSW_n() == false); setPSW_v(false); - if (dst_mode == 0) - putGAM(dst_mode, dst_reg, word_mode, vl, false); - else - b -> write(a, word_mode, vl); + put_result(a, dst_mode, dst_reg, word_mode, vl); } break; diff --git a/cpu.h b/cpu.h index 949e422..049ab32 100644 --- a/cpu.h +++ b/cpu.h @@ -104,4 +104,6 @@ public: uint16_t getRegister(const int nr) const { return getRegister(nr, false); } // FIXME remove void setRegister(const int nr, const uint16_t v) { setRegister(nr, false, v); } // FIXME remove + + void put_result(const uint16_t a, const uint8_t dst_mode, const uint8_t dst_reg, const bool word_mode, const uint16_t value); };