mirror of
https://github.com/TomHarte/CLK.git
synced 2024-07-01 14:29:51 +00:00
Settles upon disassembly as the route in, and begins work in that direction.
This commit is contained in:
Thomas Harte
parent
9e8928aad9
commit
33b53e7605
|
|
@ -10,6 +10,7 @@
|
|||
#define MC68000_h
|
||||
|
||||
#include <cstdint>
|
||||
#include <iomanip>
|
||||
#include <iostream>
|
||||
#include <vector>
|
||||
|
||||
|
|
|
|||
|
|
@ -25,6 +25,8 @@ template <class T, bool dtack_is_implicit> void Processor<T, dtack_is_implicit>:
|
|||
}
|
||||
}
|
||||
|
||||
// TODO: synchronous bus.
|
||||
|
||||
// Perform the microcycle.
|
||||
bus_handler_.perform_bus_operation(active_program_->microcycle, is_supervisor_);
|
||||
|
||||
|
|
|
|||
|
|
@ -11,8 +11,16 @@
|
|||
using namespace CPU::MC68000;
|
||||
|
||||
ProcessorStorage::ProcessorStorage() {
|
||||
// Create the reset program.
|
||||
reset_program_ = assemble_program("n- n- n- n- n- nn nF nf nV nv np np");
|
||||
|
||||
// TODO: install access patterns.
|
||||
|
||||
// Install operations.
|
||||
for(int c = 0; c < 65536; ++c) {
|
||||
install_instruction(c);
|
||||
}
|
||||
|
||||
// Set initial state. Largely TODO.
|
||||
active_program_ = reset_program_.data();
|
||||
effective_address_ = 0;
|
||||
|
|
@ -110,3 +118,94 @@ std::vector<ProcessorStorage::Step> ProcessorStorage::assemble_program(const cha
|
|||
|
||||
return steps;
|
||||
}
|
||||
|
||||
/*
|
||||
install_instruction acts, in effect, in the manner of a disassembler. So this class is
|
||||
formulated to run through all potential 65536 instuction encodings and attempt to
|
||||
disassemble each, rather than going in the opposite direction.
|
||||
|
||||
This has two benefits:
|
||||
|
||||
(i) which addressing modes go with which instructions falls out automatically;
|
||||
(ii) it is a lot easier during the manual verification stage of development to work
|
||||
from known instructions to their disassembly rather than vice versa; especially
|
||||
(iii) given that there are plentiful disassemblers against which to test work in progress.
|
||||
*/
|
||||
void ProcessorStorage::install_instruction(int instruction) {
|
||||
enum class Operation {
|
||||
ABCD, ADD, ADDA, ADDI, ADDQ, ADDX, AND, ANDI,
|
||||
ASL, ASLrmw, ASR, ASRrmw, Bcc,
|
||||
|
||||
TODO
|
||||
};
|
||||
|
||||
struct PatternMapping {
|
||||
uint16_t mask, value;
|
||||
Operation operation;
|
||||
};
|
||||
|
||||
/*
|
||||
Credit here is due to 'wrm' (https://github.com/wrm-za I assume) for his public
|
||||
domain 68000 disassembler, from which the table below was largely sourced.
|
||||
Manual legwork has been extended to check this table against the M68000
|
||||
Programmer's Reference Manual, currently available at
|
||||
https://www.nxp.com/files-static/archives/doc/ref_manual/M68000PRM.pdf
|
||||
*/
|
||||
const std::vector<PatternMapping> mappings = {
|
||||
{0xf1f0, 0xc100, Operation::ABCD}, {0xf000, 0xd000, Operation::ADD},
|
||||
{0xf0c0, 0xd0c0, Operation::ADDA}, {0xff00, 0x0600, Operation::ADDI},
|
||||
{0xf100, 0x5000, Operation::ADDQ}, {0xf130, 0xd100, Operation::ADDX},
|
||||
{0xf000, 0xc000, Operation::AND}, {0xff00, 0x0200, Operation::ANDI},
|
||||
{0xf118, 0xe100, Operation::ASL}, {0xffc0, 0xe1c0, Operation::ASLrmw},
|
||||
{0xf118, 0xe000, Operation::ASR}, {0xffc0, 0xe0c0, Operation::ASRrmw},
|
||||
{0xf000, 0x6000, Operation::Bcc}, {0xf1c0, 0x0140, Operation::TODO},
|
||||
{0xffc0, 0x0840, Operation::TODO}, {0xf1c0, 0x0180, Operation::TODO},
|
||||
{0xffc0, 0x0880, Operation::TODO}, {0xf1c0, 0x01c0, Operation::TODO},
|
||||
{0xffc0, 0x08c0, Operation::TODO}, {0xf1c0, 0x0100, Operation::TODO},
|
||||
{0xffc0, 0x0800, Operation::TODO}, {0xf1c0, 0x4180, Operation::TODO},
|
||||
{0xff00, 0x4200, Operation::TODO}, {0xf100, 0xb000, Operation::TODO},
|
||||
{0xf0c0, 0xb0c0, Operation::TODO}, {0xff00, 0x0c00, Operation::TODO},
|
||||
{0xf138, 0xb108, Operation::TODO}, {0xf0f8, 0x50c8, Operation::TODO},
|
||||
{0xf1c0, 0x81c0, Operation::TODO}, {0xf1c0, 0x80c0, Operation::TODO},
|
||||
{0xf100, 0xb100, Operation::TODO}, {0xff00, 0x0a00, Operation::TODO},
|
||||
{0xf100, 0xc100, Operation::TODO}, {0xffb8, 0x4880, Operation::TODO},
|
||||
{0xffc0, 0x4ec0, Operation::TODO}, {0xffc0, 0x4e80, Operation::TODO},
|
||||
{0xf1c0, 0x41c0, Operation::TODO}, {0xfff8, 0x4e50, Operation::TODO},
|
||||
{0xf118, 0xe108, Operation::TODO}, {0xffc0, 0xe3c0, Operation::TODO},
|
||||
{0xf118, 0xe008, Operation::TODO}, {0xffc0, 0xe2c0, Operation::TODO},
|
||||
{0xc000, 0x0000, Operation::TODO}, {0xffc0, 0x44c0, Operation::TODO},
|
||||
{0xffc0, 0x46c0, Operation::TODO}, {0xffc0, 0x40c0, Operation::TODO},
|
||||
{0xfff0, 0x4e60, Operation::TODO}, {0xc1c0, 0x0040, Operation::TODO},
|
||||
{0xfb80, 0x4880, Operation::TODO}, {0xf138, 0x0108, Operation::TODO},
|
||||
{0xf100, 0x7000, Operation::TODO}, {0xf1c0, 0xc1c0, Operation::TODO},
|
||||
{0xf1c0, 0xc0c0, Operation::TODO}, {0xffc0, 0x4800, Operation::TODO},
|
||||
{0xff00, 0x4400, Operation::TODO}, {0xff00, 0x4000, Operation::TODO},
|
||||
{0xffff, 0x4e71, Operation::TODO}, {0xff00, 0x4600, Operation::TODO},
|
||||
{0xf000, 0x8000, Operation::TODO}, {0xff00, 0x0000, Operation::TODO},
|
||||
{0xffc0, 0x4840, Operation::TODO}, {0xffff, 0x4e70, Operation::TODO},
|
||||
{0xf118, 0xe118, Operation::TODO}, {0xffc0, 0xe7c0, Operation::TODO},
|
||||
{0xf118, 0xe018, Operation::TODO}, {0xffc0, 0xe6c0, Operation::TODO},
|
||||
{0xf118, 0xe110, Operation::TODO}, {0xffc0, 0xe5c0, Operation::TODO},
|
||||
{0xf118, 0xe010, Operation::TODO}, {0xffc0, 0xe4c0, Operation::TODO},
|
||||
{0xffff, 0x4e73, Operation::TODO}, {0xffff, 0x4e77, Operation::TODO},
|
||||
{0xffff, 0x4e75, Operation::TODO}, {0xf1f0, 0x8100, Operation::TODO},
|
||||
{0xf0c0, 0x50c0, Operation::TODO}, {0xffff, 0x4e72, Operation::TODO},
|
||||
{0xf000, 0x9000, Operation::TODO}, {0xf0c0, 0x90c0, Operation::TODO},
|
||||
{0xff00, 0x0400, Operation::TODO}, {0xf100, 0x5100, Operation::TODO},
|
||||
{0xf130, 0x9100, Operation::TODO}, {0xfff8, 0x4840, Operation::TODO},
|
||||
{0xffc0, 0x4ac0, Operation::TODO}, {0xfff0, 0x4e40, Operation::TODO},
|
||||
{0xffff, 0x4e76, Operation::TODO}, {0xff00, 0x4a00, Operation::TODO},
|
||||
{0xfff8, 0x4e58, Operation::TODO}
|
||||
};
|
||||
|
||||
// Perform a linear search of the mappings above for this instruction.
|
||||
for(const auto &mapping: mappings) {
|
||||
if((instruction & mapping.mask) == mapping.value) {
|
||||
if(mapping.operation == Operation::TODO) {
|
||||
std::cout << std::hex << std::setw(4) << std::setfill('0');
|
||||
std::cout << "Yet to implement, instruction matching: x & " << mapping.mask << " == " << mapping.value << std::endl;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -104,6 +104,12 @@ class ProcessorStorage {
|
|||
data from those.
|
||||
*/
|
||||
std::vector<Step> assemble_program(const char *access_pattern);
|
||||
|
||||
/*!
|
||||
Disassembles the instruction @c instruction and inserts it into the
|
||||
appropriate lookup tables.
|
||||
*/
|
||||
void install_instruction(int instruction);
|
||||
};
|
||||
|
||||
#endif /* MC68000Storage_h */
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user