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Merge pull request #1093 from TomHarte/IIgsFill

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Apple IIgs: better spell out shadowing logic.
This commit is contained in:
Thomas Harte 2022-09-13 16:45:49 -04:00 committed by GitHub
commit 7e3dbbbf0a
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3 changed files with 92 additions and 20 deletions
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1
Machines/Apple/AppleIIgs/AppleIIgs.cpp
View File

@ -200,6 +200,7 @@ class ConcreteMachine:
public:
ConcreteMachine(const Analyser::Static::AppleIIgs::Target &target, const ROMMachine::ROMFetcher &rom_fetcher) :
m65816_(*this),
memory_(target.model >= Analyser::Static::AppleIIgs::Target::Model::ROM03),
iwm_(CLOCK_RATE / 2),
drives35_{
{CLOCK_RATE / 2, true},

106
Machines/Apple/AppleIIgs/MemoryMap.hpp
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@ -26,7 +26,9 @@ class MemoryMap {
public:
// MARK: - Initial construction and configuration.
MemoryMap() : auxiliary_switches_(*this), language_card_(*this) {}
MemoryMap(bool is_rom03) : auxiliary_switches_(*this), language_card_(*this) {
setup_shadow_maps(is_rom03);
}
void set_storage(std::vector<uint8_t> &ram, std::vector<uint8_t> &rom) {
// Keep a pointer for later; also note the proper RAM offset.
@ -456,9 +458,6 @@ class MemoryMap {
// $6000–$a000 Odd banks only, rest of Super High-res
// [plus IO and language card space, subject to your definition of shadowing]
static constexpr int shadow_shift = 10;
static constexpr int auxiliary_offset = 0x1'0000 >> shadow_shift;
enum Inhibit {
TextPage1 = 0x01,
HighRes1 = 0x02,
@ -468,15 +467,25 @@ class MemoryMap {
TextPage2 = 0x20,
};
// Clear all shadowing.
shadow_pages.reset();
// Text Page 1, main and auxiliary — $0400–$0800.
for(size_t c = 0x0400 >> shadow_shift; c < 0x0800 >> shadow_shift; c++) {
shadow_pages[c] = shadow_pages[c+auxiliary_offset] = !(shadow_register_ & Inhibit::TextPage1);
{
const bool should_shadow_text1 = !(shadow_register_ & Inhibit::TextPage1);
if(should_shadow_text1) {
shadow_pages |= shadow_text1;
}
}
// Text Page 2, main and auxiliary — 0x0800–0x0c00.
// TODO: on a ROM03 machine only.
for(size_t c = 0x0800 >> shadow_shift; c < 0x0c00 >> shadow_shift; c++) {
shadow_pages[c] = shadow_pages[c+auxiliary_offset] = !(shadow_register_ & Inhibit::TextPage2);
//
// The mask applied will be all 0 for a pre-ROM03 machine.
{
const bool should_shadow_text2 = !(shadow_register_ & Inhibit::TextPage2);
if(should_shadow_text2) {
shadow_pages |= shadow_text2;
}
}
// Hi-res graphics Page 1, main and auxiliary — $2000–$4000;
@ -486,35 +495,55 @@ class MemoryMap {
// high-res graphics page 1 inhibit bit alone is definitive.
//
// Odd test:
// (high-res graphics inhibit or auxiliary high res graphics inhibit) _and_ (super high-res inhibit).
// (high-res graphics inhibit or auxiliary high res graphics inhibit) _and_
// (super high-res inhibit).
//
for(size_t c = 0x2000 >> shadow_shift; c < 0x4000 >> shadow_shift; c++) {
shadow_pages[c] = !(shadow_register_ & Inhibit::HighRes1);
shadow_pages[c+auxiliary_offset] = !(
{
const bool should_shadow_highres1 = !(shadow_register_ & Inhibit::HighRes1);
if(should_shadow_highres1) {
shadow_pages |= shadow_highres1;
}
const bool should_shadow_aux_highres1 = !(
shadow_register_ & (Inhibit::HighRes1 | Inhibit::AuxiliaryHighRes) &&
shadow_register_ & Inhibit::SuperHighRes
);
if(should_shadow_aux_highres1) {
shadow_pages |= shadow_highres1_aux;
}
}
// Hi-res graphics Page 2, main and auxiliary — $4000–$6000;
// also part of the super high-res graphics page.
//
// Test applied: much like that for page 1.
for(size_t c = 0x4000 >> shadow_shift; c < 0x6000 >> shadow_shift; c++) {
shadow_pages[c] = !(shadow_register_ & Inhibit::HighRes2);
shadow_pages[c+auxiliary_offset] = !(
{
const bool should_shadow_highres2 = !(shadow_register_ & Inhibit::HighRes2);
if(should_shadow_highres2) {
shadow_pages |= shadow_highres2;
}
const bool should_shadow_aux_highres2 = !(
shadow_register_ & (Inhibit::HighRes2 | Inhibit::AuxiliaryHighRes) &&
shadow_register_ & Inhibit::SuperHighRes
);
if(should_shadow_aux_highres2) {
shadow_pages |= shadow_highres2_aux;
}
}
// Residue of Super Hi-Res — $6000–$a000 (odd pages only).
//
// Test applied:
// auxiliary high res graphics inhibit and super high-res inhibit
for(size_t c = 0x6000 >> shadow_shift; c < 0xa000 >> shadow_shift; c++) {
shadow_pages[c+auxiliary_offset] =
!(shadow_register_ & Inhibit::SuperHighRes && shadow_register_ & Inhibit::AuxiliaryHighRes);
{
const bool should_shadow_superhighres = !(
shadow_register_ & Inhibit::SuperHighRes &&
shadow_register_ & Inhibit::AuxiliaryHighRes
);
if(should_shadow_superhighres) {
shadow_pages |= shadow_superhighres;
}
}
}
@ -537,6 +566,45 @@ class MemoryMap {
#undef assert_is_region
private:
// Various precomputed bitsets describing key regions; std::bitset doesn't support constexpr instantiation
// beyond the first 64 bits at the time of writing, alas, so these are generated at runtime.
std::bitset<128> shadow_text1;
std::bitset<128> shadow_text2;
std::bitset<128> shadow_highres1, shadow_highres1_aux;
std::bitset<128> shadow_highres2, shadow_highres2_aux;
std::bitset<128> shadow_superhighres;
void setup_shadow_maps(bool is_rom03) {
static constexpr int shadow_shift = 10;
static constexpr int auxiliary_offset = 0x1'0000 >> shadow_shift;
for(size_t c = 0x0400 >> shadow_shift; c < 0x0800 >> shadow_shift; c++) {
shadow_text1[c] = shadow_text1[c+auxiliary_offset] = true;
}
// Shadowing of text page 2 was added only with the ROM03 machine.
if(is_rom03) {
for(size_t c = 0x0800 >> shadow_shift; c < 0x0c00 >> shadow_shift; c++) {
shadow_text2[c] = shadow_text2[c+auxiliary_offset] = true;
}
}
for(size_t c = 0x2000 >> shadow_shift; c < 0x4000 >> shadow_shift; c++) {
shadow_highres1[c] = true;
shadow_highres1_aux[c+auxiliary_offset] = true;
}
for(size_t c = 0x4000 >> shadow_shift; c < 0x6000 >> shadow_shift; c++) {
shadow_highres2[c] = true;
shadow_highres2_aux[c+auxiliary_offset] = true;
}
for(size_t c = 0x6000 >> shadow_shift; c < 0xa000 >> shadow_shift; c++) {
shadow_superhighres[c+auxiliary_offset] = true;
}
}
public:
// Memory layout here is done via double indirection; the main loop should:
// (i) use the top two bytes of the address to get an index from memory_map_; and

5
OSBindings/Mac/Clock SignalTests/IIgsMemoryMapTests.mm
View File

@ -11,7 +11,10 @@
#include "../../../Machines/Apple/AppleIIgs/MemoryMap.hpp"
namespace {
using MemoryMap = Apple::IIgs::MemoryMap;
// Test the ROM03-era mapping hardware.
struct MemoryMap: public Apple::IIgs::MemoryMap {
MemoryMap() : Apple::IIgs::MemoryMap(true) {}
};
}
@interface IIgsMemoryMapTests : XCTestCase