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fixes for re-adding upper byte for single-byte instructions

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This commit is contained in:
folkert van heusden 2022-03-31 13:22:58 +02:00
parent 1ea4658257
commit bf452aede1
1 changed files with 13 additions and 7 deletions
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20
cpu.cpp
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@ -752,12 +752,13 @@ bool cpu::single_operand_instructions(const uint16_t instr)
uint16_t add = word_mode ? v & 0xff00 : 0;
v = (v - 1) & (word_mode ? 0xff : 0xffff);
v |= add;
setPSW_n(SIGN(v, word_mode));
setPSW_z(v == 0);
setPSW_v(word_mode ? v == 0x7f : v == 0x7fff);
setRegister(dst_reg, false, v | add);
setRegister(dst_reg, false, v);
}
else {
uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false);
@ -780,12 +781,13 @@ bool cpu::single_operand_instructions(const uint16_t instr)
uint16_t add = word_mode ? v & 0xff00 : 0;
v = (-v) & (word_mode ? 0xff : 0xffff);
v |= add;
setPSW_n(SIGN(v, word_mode));
setPSW_z(v == 0);
setPSW_v(word_mode ? v == 0x80 : v == 0x8000);
setRegister(dst_reg, false, v | add);
setRegister(dst_reg, false, v);
}
else {
uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false);
@ -810,13 +812,14 @@ bool cpu::single_operand_instructions(const uint16_t instr)
bool org_c = getPSW_c();
v = (v + org_c) & (word_mode ? 0xff : 0xffff);
v |= add;
setPSW_n(SIGN(v, word_mode));
setPSW_z(v == 0);
setPSW_v((word_mode ? v == 0x80 : v == 0x8000) && org_c);
setPSW_c((word_mode ? v == 0x00 : v == 0x0000) && org_c);
setRegister(dst_reg, false, v | add);
setRegister(dst_reg, false, v);
}
else {
uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false);
@ -841,13 +844,14 @@ bool cpu::single_operand_instructions(const uint16_t instr)
bool org_c = getPSW_c();
v = (v - org_c) & (word_mode ? 0xff : 0xffff);
v |= add;
setPSW_n(SIGN(v, word_mode));
setPSW_z(v == 0);
setPSW_v((word_mode ? v == 0x7f : v == 0x7fff) && org_c);
setPSW_c((word_mode ? v == 0xff : v == 0xffff) && org_c);
setRegister(dst_reg, false, v | add);
setRegister(dst_reg, false, v);
}
else {
uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false);
@ -1025,16 +1029,18 @@ bool cpu::single_operand_instructions(const uint16_t instr)
case 0b00110011: { // ASL/ASLB
if (dst_mode == 0) {
int32_t vl = getRegister(dst_reg, false);
uint16_t vl = getRegister(dst_reg, false);
uint16_t add = word_mode ? vl & 0xff00 : 0;
uint16_t v = (vl << 1) & (word_mode ? 0xff : 0xffff);
uint16_t add = word_mode ? v & 0xff00 : 0;
v |= add;
setPSW_n(SIGN(v, word_mode));
setPSW_z(v == 0);
setPSW_c(word_mode ? vl & 0x80 : vl & 0x8000);
setPSW_v(getPSW_n() ^ getPSW_c());
setRegister(dst_reg, false, v | add);
setRegister(dst_reg, false, v);
}
else {
uint16_t a = getGAMAddress(dst_mode, dst_reg, word_mode, false);