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Seemingly advances to the first indefinite loop.

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This commit is contained in:
Thomas Harte 2021-01-20 21:18:52 -05:00
parent cf8afc70b2
commit ebdb58d790
2 changed files with 46 additions and 8 deletions
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46
InstructionSets/M50740/Executor.cpp
View File

@ -37,7 +37,7 @@ void Executor::set_rom(const std::vector<uint8_t> &rom) {
reset();
// TEMPORARY: just to test initial wiring.
for(int c = 0; c < 130; c++) {
for(int c = 0; c < 1300; c++) {
run_to_branch();
}
}
@ -184,6 +184,7 @@ template <Operation operation, AddressingMode addressing_mode> void Executor::pe
case Operation::BBC4: case Operation::BBC5: case Operation::BBC6: case Operation::BBC7:
if(value & (1 << (int(operation) - int(Operation::BBC0)))) set_program_counter(uint16_t(address));
return;
default: assert(false);
}
} break;
@ -267,6 +268,7 @@ template <Operation operation, AddressingMode addressing_mode> void Executor::pe
}
template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_unused]]) {
#define set_nz(a) negative_result_ = zero_result_ = (a)
switch(operation) {
case Operation::LDA: set_nz(a_ = *operand); break;
@ -327,9 +329,6 @@ template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_u
// after exiting from here.
} break;
case Operation::ORA: set_nz(a_ |= *operand); break;
case Operation::AND: set_nz(a_ &= *operand); break;
case Operation::EOR: set_nz(a_ ^= *operand); break;
case Operation::COM: set_nz(*operand ^= 0xff); break;
case Operation::FST: case Operation::SLW: case Operation::NOP:
@ -344,11 +343,42 @@ template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_u
// TODO:
//
// BRK, STP,
// ADC, SBC, BIT, CMP, CPX, CPY, ASL, LSR, ROL, ROR, RRF
// ADC, SBC, BIT, ASL, LSR, ROL, ROR, RRF
/*
Operations affected by the index mode flag: ADC, AND, CMP, EOR, LDA, ORA, and SBC.
*/
/*
Operations affected by the index mode flag: ADC, AND, CMP, EOR, LDA, ORA, and SBC.
*/
#define index(op) \
if(index_mode_) { \
uint8_t t = read(x_); \
op(t); \
write(x_, t); \
} else { \
op(a_); \
}
#define op_ora(x) set_nz(x |= *operand)
#define op_and(x) set_nz(x &= *operand)
#define op_eor(x) set_nz(x ^= *operand)
case Operation::ORA: index(op_ora); break;
case Operation::AND: index(op_and); break;
case Operation::EOR: index(op_eor); break;
#undef op_eor
#undef op_and
#undef op_ora
#define op_cmp(x) { \
const uint16_t temp16 = x - *operand; \
set_nz(uint8_t(temp16)); \
carry_flag_ = (~temp16 >> 8)&1; \
}
case Operation::CMP: index(op_cmp); break;
case Operation::CPX: op_cmp(x_); break;
case Operation::CPY: op_cmp(y_); break;
#undef op_cmp
#undef index
/*
Already removed from the instruction stream:

8
InstructionSets/M50740/Instruction.hpp
View File

@ -98,6 +98,14 @@ constexpr AccessType access_type(Operation operation) {
return AccessType::ReadModifyWrite;
}
constexpr bool uses_index_mode(Operation operation) {
return
operation == Operation::ADC || operation == Operation::AND ||
operation == Operation::CMP || operation == Operation::EOR ||
operation == Operation::LDA || operation == Operation::ORA ||
operation == Operation::SBC;
}
struct Instruction {
Operation operation = Operation::Invalid;
AddressingMode addressing_mode = AddressingMode::Implied;