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Simplified CommaVid test.

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This commit is contained in:
Thomas Harte 2017-03-12 22:14:39 -04:00
parent b671df9906
commit a9964ee0c8
1 changed files with 11 additions and 48 deletions
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59
StaticAnalyser/Atari/StaticAnalyser.cpp
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@ -27,56 +27,21 @@ static void DeterminePagingFor2kCartridge(StaticAnalyser::Target &target, const
address &= 0x1fff;
return (size_t)(address - 0x1800);
};
std::function<size_t(uint16_t address)> full_range_mapper = [](uint16_t address) {
if(!(address & 0x1000)) return (size_t)-1;
return (size_t)(address & 0x7ff);
};
StaticAnalyser::MOS6502::Disassembly high_location_disassembly =
StaticAnalyser::MOS6502::Disassemble(segment.data, high_location_mapper, {entry_address, break_address});
// if there are no subroutines in the top 2kb of memory then this isn't a CommaVid
bool has_appropriate_subroutine_calls = false;
bool has_inappropriate_subroutine_calls = false;
for(uint16_t address : high_location_disassembly.internal_calls)
{
const uint16_t masked_address = address & 0x1fff;
has_appropriate_subroutine_calls |= (masked_address >= 0x1800);
has_inappropriate_subroutine_calls |= (masked_address < 0x1800);
}
// assumption here: a CommaVid will never branch into RAM. Possibly unsafe: if it won't then what's the RAM for?
if(!has_appropriate_subroutine_calls || has_inappropriate_subroutine_calls) return;
std::set<uint16_t> all_writes = high_location_disassembly.external_stores;
all_writes.insert(high_location_disassembly.external_modifies.begin(), high_location_disassembly.external_modifies.end());
// a CommaVid will use its RAM
if(all_writes.empty()) return;
bool has_appropriate_accesses = false;
for(uint16_t address : all_writes)
{
const uint16_t masked_address = address & 0x1fff;
if(masked_address >= 0x1400 && masked_address < 0x1800)
{
has_appropriate_accesses = true;
break;
}
}
// in desperation, accept any kind of store that looks likely to be intended for large amounts of memory
// assume that any kind of store that looks likely to be intended for large amounts of memory implies
// large amounts of memory
bool has_wide_area_store = false;
if(!has_appropriate_accesses)
for(std::map<uint16_t, StaticAnalyser::MOS6502::Instruction>::value_type &entry : high_location_disassembly.instructions_by_address)
{
for(std::map<uint16_t, StaticAnalyser::MOS6502::Instruction>::value_type &entry : high_location_disassembly.instructions_by_address)
if(entry.second.operation == StaticAnalyser::MOS6502::Instruction::STA)
{
if(entry.second.operation == StaticAnalyser::MOS6502::Instruction::STA)
{
has_wide_area_store |= entry.second.addressing_mode == StaticAnalyser::MOS6502::Instruction::Indirect;
has_wide_area_store |= entry.second.addressing_mode == StaticAnalyser::MOS6502::Instruction::IndexedIndirectX;
has_wide_area_store |= entry.second.addressing_mode == StaticAnalyser::MOS6502::Instruction::IndirectIndexedY;
}
has_wide_area_store |= entry.second.addressing_mode == StaticAnalyser::MOS6502::Instruction::Indirect;
has_wide_area_store |= entry.second.addressing_mode == StaticAnalyser::MOS6502::Instruction::IndexedIndirectX;
has_wide_area_store |= entry.second.addressing_mode == StaticAnalyser::MOS6502::Instruction::IndirectIndexedY;
if(has_wide_area_store) break;
}
}
@ -84,8 +49,7 @@ static void DeterminePagingFor2kCartridge(StaticAnalyser::Target &target, const
// caveat: false positives aren't likely to be problematic; a false positive is a 2KB ROM that always addresses
// itself so as to land in ROM even if mapped as a CommaVid and this code is on the fence as to whether it
// attempts to modify itself but it probably doesn't
if(has_appropriate_accesses || has_wide_area_store)
target.atari.paging_model = StaticAnalyser::Atari2600PagingModel::CommaVid;
if(has_wide_area_store) target.atari.paging_model = StaticAnalyser::Atari2600PagingModel::CommaVid;
}
static void DeterminePagingFor8kCartridge(StaticAnalyser::Target &target, const Storage::Cartridge::Cartridge::Segment &segment, const StaticAnalyser::MOS6502::Disassembly &disassembly)
@ -223,8 +187,7 @@ void StaticAnalyser::Atari::AddTargets(
const std::list<std::shared_ptr<Storage::Cartridge::Cartridge>> &cartridges,
std::list<StaticAnalyser::Target> &destination)
{
// TODO: any sort of sanity checking at all; at the minute just trust the file type
// approximation already performed.
// TODO: sanity checking; is this image really for an Atari 2600?
Target target;
target.machine = Target::Atari2600;
target.probability = 1.0;