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583 lines
20 KiB
C++
583 lines
20 KiB
C++
//
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// Blitter.cpp
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// Clock Signal
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//
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// Created by Thomas Harte on 22/07/2021.
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// Copyright © 2021 Thomas Harte. All rights reserved.
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//
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#include "Blitter.hpp"
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#include "Minterms.hpp"
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#include <cassert>
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#ifndef NDEBUG
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#define NDEBUG
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#endif
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#define LOG_PREFIX "[Blitter] "
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#include "../../Outputs/Log.hpp"
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using namespace Amiga;
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namespace {
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/// @returns Either the final carry flag or the output nibble when using fill mode given that it either @c is_exclusive fill mode, or isn't;
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/// and the specified initial @c carry and input @c nibble.
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template <bool wants_carry> constexpr uint32_t fill_nibble(bool is_exclusive, uint8_t carry, uint8_t nibble) {
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uint8_t fill_output = 0;
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uint8_t bit = 0x01;
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while(bit < 0x10) {
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auto pre_toggle = nibble & bit, post_toggle = pre_toggle;
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if(!is_exclusive) {
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pre_toggle &= ~carry; // Accept bits that would transition to set immediately.
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post_toggle &= carry; // Accept bits that would transition to clear after the fact.
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} else {
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post_toggle = 0; // Just do the pre-toggle.
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}
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carry ^= pre_toggle;
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fill_output |= carry;
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carry ^= post_toggle;
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bit <<= 1;
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carry <<= 1;
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}
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if constexpr (wants_carry) {
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return carry >> 4;
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} else {
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return fill_output;
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}
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}
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// Lookup key for these tables is:
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//
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// b0–b3: input nibble
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// b4: carry
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// b5: is_exclusive
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//
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// i.e. it's in the range [0, 63].
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//
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// Tables below are indexed such that the higher-order bits select a table entry, lower-order bits select
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// a bit or nibble from within the indexed item.
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constexpr uint32_t fill_carries[] = {
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(fill_nibble<true>(false, 0, 0x0) << 0x0) | (fill_nibble<true>(false, 0, 0x1) << 0x1) | (fill_nibble<true>(false, 0, 0x2) << 0x2) | (fill_nibble<true>(false, 0, 0x3) << 0x3) |
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(fill_nibble<true>(false, 0, 0x4) << 0x4) | (fill_nibble<true>(false, 0, 0x5) << 0x5) | (fill_nibble<true>(false, 0, 0x6) << 0x6) | (fill_nibble<true>(false, 0, 0x7) << 0x7) |
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(fill_nibble<true>(false, 0, 0x8) << 0x8) | (fill_nibble<true>(false, 0, 0x9) << 0x9) | (fill_nibble<true>(false, 0, 0xa) << 0xa) | (fill_nibble<true>(false, 0, 0xb) << 0xb) |
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(fill_nibble<true>(false, 0, 0xc) << 0xc) | (fill_nibble<true>(false, 0, 0xd) << 0xd) | (fill_nibble<true>(false, 0, 0xe) << 0xe) | (fill_nibble<true>(false, 0, 0xf) << 0xf) |
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(fill_nibble<true>(false, 1, 0x0) << 0x10) | (fill_nibble<true>(false, 1, 0x1) << 0x11) | (fill_nibble<true>(false, 1, 0x2) << 0x12) | (fill_nibble<true>(false, 1, 0x3) << 0x13) |
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(fill_nibble<true>(false, 1, 0x4) << 0x14) | (fill_nibble<true>(false, 1, 0x5) << 0x15) | (fill_nibble<true>(false, 1, 0x6) << 0x16) | (fill_nibble<true>(false, 1, 0x7) << 0x17) |
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(fill_nibble<true>(false, 1, 0x8) << 0x18) | (fill_nibble<true>(false, 1, 0x9) << 0x19) | (fill_nibble<true>(false, 1, 0xa) << 0x1a) | (fill_nibble<true>(false, 1, 0xb) << 0x1b) |
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(fill_nibble<true>(false, 1, 0xc) << 0x1c) | (fill_nibble<true>(false, 1, 0xd) << 0x1d) | (fill_nibble<true>(false, 1, 0xe) << 0x1e) | (fill_nibble<true>(false, 1, 0xf) << 0x1f),
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(fill_nibble<true>(true, 0, 0x0) << 0x0) | (fill_nibble<true>(true, 0, 0x1) << 0x1) | (fill_nibble<true>(true, 0, 0x2) << 0x2) | (fill_nibble<true>(true, 0, 0x3) << 0x3) |
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(fill_nibble<true>(true, 0, 0x4) << 0x4) | (fill_nibble<true>(true, 0, 0x5) << 0x5) | (fill_nibble<true>(true, 0, 0x6) << 0x6) | (fill_nibble<true>(true, 0, 0x7) << 0x7) |
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(fill_nibble<true>(true, 0, 0x8) << 0x8) | (fill_nibble<true>(true, 0, 0x9) << 0x9) | (fill_nibble<true>(true, 0, 0xa) << 0xa) | (fill_nibble<true>(true, 0, 0xb) << 0xb) |
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(fill_nibble<true>(true, 0, 0xc) << 0xc) | (fill_nibble<true>(true, 0, 0xd) << 0xd) | (fill_nibble<true>(true, 0, 0xe) << 0xe) | (fill_nibble<true>(true, 0, 0xf) << 0xf) |
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(fill_nibble<true>(true, 1, 0x0) << 0x10) | (fill_nibble<true>(true, 1, 0x1) << 0x11) | (fill_nibble<true>(true, 1, 0x2) << 0x12) | (fill_nibble<true>(true, 1, 0x3) << 0x13) |
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(fill_nibble<true>(true, 1, 0x4) << 0x14) | (fill_nibble<true>(true, 1, 0x5) << 0x15) | (fill_nibble<true>(true, 1, 0x6) << 0x16) | (fill_nibble<true>(true, 1, 0x7) << 0x17) |
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(fill_nibble<true>(true, 1, 0x8) << 0x18) | (fill_nibble<true>(true, 1, 0x9) << 0x19) | (fill_nibble<true>(true, 1, 0xa) << 0x1a) | (fill_nibble<true>(true, 1, 0xb) << 0x1b) |
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(fill_nibble<true>(true, 1, 0xc) << 0x1c) | (fill_nibble<true>(true, 1, 0xd) << 0x1d) | (fill_nibble<true>(true, 1, 0xe) << 0x1e) | (fill_nibble<true>(true, 1, 0xf) << 0x1f),
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};
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constexpr uint32_t fill_values[] = {
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(fill_nibble<false>(false, 0, 0x0) << 0) | (fill_nibble<false>(false, 0, 0x1) << 4) | (fill_nibble<false>(false, 0, 0x2) << 8) | (fill_nibble<false>(false, 0, 0x3) << 12) |
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(fill_nibble<false>(false, 0, 0x4) << 16) | (fill_nibble<false>(false, 0, 0x5) << 20) | (fill_nibble<false>(false, 0, 0x6) << 24) | (fill_nibble<false>(false, 0, 0x7) << 28),
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(fill_nibble<false>(false, 0, 0x8) << 0) | (fill_nibble<false>(false, 0, 0x9) << 4) | (fill_nibble<false>(false, 0, 0xa) << 8) | (fill_nibble<false>(false, 0, 0xb) << 12) |
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(fill_nibble<false>(false, 0, 0xc) << 16) | (fill_nibble<false>(false, 0, 0xd) << 20) | (fill_nibble<false>(false, 0, 0xe) << 24) | (fill_nibble<false>(false, 0, 0xf) << 28),
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(fill_nibble<false>(false, 1, 0x0) << 0) | (fill_nibble<false>(false, 1, 0x1) << 4) | (fill_nibble<false>(false, 1, 0x2) << 8) | (fill_nibble<false>(false, 1, 0x3) << 12) |
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(fill_nibble<false>(false, 1, 0x4) << 16) | (fill_nibble<false>(false, 1, 0x5) << 20) | (fill_nibble<false>(false, 1, 0x6) << 24) | (fill_nibble<false>(false, 1, 0x7) << 28),
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(fill_nibble<false>(false, 1, 0x8) << 0) | (fill_nibble<false>(false, 1, 0x9) << 4) | (fill_nibble<false>(false, 1, 0xa) << 8) | (fill_nibble<false>(false, 1, 0xb) << 12) |
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(fill_nibble<false>(false, 1, 0xc) << 16) | (fill_nibble<false>(false, 1, 0xd) << 20) | (fill_nibble<false>(false, 1, 0xe) << 24) | (fill_nibble<false>(false, 1, 0xf) << 28),
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(fill_nibble<false>(true, 0, 0x0) << 0) | (fill_nibble<false>(true, 0, 0x1) << 4) | (fill_nibble<false>(true, 0, 0x2) << 8) | (fill_nibble<false>(true, 0, 0x3) << 12) |
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(fill_nibble<false>(true, 0, 0x4) << 16) | (fill_nibble<false>(true, 0, 0x5) << 20) | (fill_nibble<false>(true, 0, 0x6) << 24) | (fill_nibble<false>(true, 0, 0x7) << 28),
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(fill_nibble<false>(true, 0, 0x8) << 0) | (fill_nibble<false>(true, 0, 0x9) << 4) | (fill_nibble<false>(true, 0, 0xa) << 8) | (fill_nibble<false>(true, 0, 0xb) << 12) |
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(fill_nibble<false>(true, 0, 0xc) << 16) | (fill_nibble<false>(true, 0, 0xd) << 20) | (fill_nibble<false>(true, 0, 0xe) << 24) | (fill_nibble<false>(true, 0, 0xf) << 28),
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(fill_nibble<false>(true, 1, 0x0) << 0) | (fill_nibble<false>(true, 1, 0x1) << 4) | (fill_nibble<false>(true, 1, 0x2) << 8) | (fill_nibble<false>(true, 1, 0x3) << 12) |
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(fill_nibble<false>(true, 1, 0x4) << 16) | (fill_nibble<false>(true, 1, 0x5) << 20) | (fill_nibble<false>(true, 1, 0x6) << 24) | (fill_nibble<false>(true, 1, 0x7) << 28),
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(fill_nibble<false>(true, 1, 0x8) << 0) | (fill_nibble<false>(true, 1, 0x9) << 4) | (fill_nibble<false>(true, 1, 0xa) << 8) | (fill_nibble<false>(true, 1, 0xb) << 12) |
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(fill_nibble<false>(true, 1, 0xc) << 16) | (fill_nibble<false>(true, 1, 0xd) << 20) | (fill_nibble<false>(true, 1, 0xe) << 24) | (fill_nibble<false>(true, 1, 0xf) << 28),
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};
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}
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template <bool record_bus>
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void Blitter<record_bus>::set_control(int index, uint16_t value) {
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if(index) {
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line_mode_ = (value & 0x0001);
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one_dot_ = value & 0x0002;
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line_direction_ = (value >> 2) & 7;
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line_sign_ = (value & 0x0040) ? -1 : 1;
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direction_ = one_dot_ ? uint32_t(-1) : uint32_t(1);
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exclusive_fill_ = (value & 0x0010);
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inclusive_fill_ = !exclusive_fill_ && (value & 0x0008); // Exclusive fill takes precedence. Probably? TODO: verify.
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fill_carry_ = (value & 0x0004);
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} else {
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minterms_ = value & 0xff;
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sequencer_.set_control(value >> 8);
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}
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shifts_[index] = value >> 12;
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LOG("Set control " << index << " to " << PADHEX(4) << value);
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}
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template <bool record_bus>
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void Blitter<record_bus>::set_first_word_mask(uint16_t value) {
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LOG("Set first word mask: " << PADHEX(4) << value);
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a_mask_[0] = value;
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}
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template <bool record_bus>
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void Blitter<record_bus>::set_last_word_mask(uint16_t value) {
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LOG("Set last word mask: " << PADHEX(4) << value);
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a_mask_[1] = value;
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}
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template <bool record_bus>
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void Blitter<record_bus>::set_size(uint16_t value) {
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// width_ = (width_ & ~0x3f) | (value & 0x3f);
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// height_ = (height_ & ~0x3ff) | (value >> 6);
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width_ = value & 0x3f;
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if(!width_) width_ = 0x40;
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height_ = value >> 6;
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if(!height_) height_ = 1024;
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LOG("Set size to " << std::dec << width_ << ", " << height_);
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// Current assumption: writing this register informs the
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// blitter that it should treat itself as about to start a new line.
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}
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template <bool record_bus>
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void Blitter<record_bus>::set_minterms(uint16_t value) {
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LOG("Set minterms " << PADHEX(4) << value);
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minterms_ = value & 0xff;
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}
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//template <bool record_bus>
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//void Blitter<record_bus>::set_vertical_size([[maybe_unused]] uint16_t value) {
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// LOG("Set vertical size " << PADHEX(4) << value);
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// // TODO. This is ECS only, I think. Ditto set_horizontal_size.
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//}
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//
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//template <bool record_bus>
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//void Blitter<record_bus>::set_horizontal_size([[maybe_unused]] uint16_t value) {
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// LOG("Set horizontal size " << PADHEX(4) << value);
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//}
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template <bool record_bus>
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void Blitter<record_bus>::set_data(int channel, uint16_t value) {
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LOG("Set data " << channel << " to " << PADHEX(4) << value);
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// Ugh, backed myself into a corner. TODO: clean.
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switch(channel) {
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case 0: a_data_ = value; break;
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case 1: b_data_ = value; break;
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case 2: c_data_ = value; break;
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default: break;
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}
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}
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template <bool record_bus>
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uint16_t Blitter<record_bus>::get_status() {
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const uint16_t result =
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(not_zero_flag_ ? 0x0000 : 0x2000) | (height_ ? 0x4000 : 0x0000);
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LOG("Returned status of " << result);
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return result;
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}
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// Due to the pipeline, writes are delayed by one slot — the first write will occur
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// after the second set of inputs has been fetched, and every sequence with writes enabled
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// will end with an additional write.
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//
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// USE Code
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// in Active
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// BLTCON0 Channels Cycle Sequence
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// --------- -------- --------------
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// F A B C D A0 B0 C0 - A1 B1 C1 D0 A2 B2 C2 D1 D2
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// E A B C A0 B0 C0 A1 B1 C1 A2 B2 C2
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// D A B D A0 B0 - A1 B1 D0 A2 B2 D1 - D2
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// C A B A0 B0 - A1 B1 - A2 B2
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// B A C D A0 C0 - A1 C1 D0 A2 C2 D1 - D2
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// A A C A0 C0 A1 C1 A2 C2
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// 9 A D A0 - A1 D0 A2 D1 - D2
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// 8 A A0 - A1 - A2
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// 7 B C D B0 C0 - - B1 C1 D0 - B2 C2 D1 - D2
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// 6 B C B0 C0 - B1 C1 - B2 C2
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// 5 B D B0 - - B1 D0 - B2 D1 - D2
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// 4 B B0 - - B1 - - B2
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// 3 C D C0 - - C1 D0 - C2 D1 - D2
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// 2 C C0 - C1 - C2
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// 1 D D0 - D1 - D2
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// 0 none - - - -
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//
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//
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// Table 6-2: Typical Blitter Cycle Sequence
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template <bool record_bus>
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void Blitter<record_bus>::add_modulos() {
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pointer_[0] += modulos_[0] * sequencer_.channel_enabled<0>()* direction_;
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pointer_[1] += modulos_[1] * sequencer_.channel_enabled<1>() * direction_;
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pointer_[2] += modulos_[2] * sequencer_.channel_enabled<2>() * direction_;
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pointer_[3] += modulos_[3] * sequencer_.channel_enabled<3>() * direction_;
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}
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template <bool record_bus>
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template <bool complete_immediately>
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bool Blitter<record_bus>::advance_dma() {
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if(!height_) return false;
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// TODO: eliminate @c complete_immediately and this workaround.
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// See commentary in Chipset.cpp.
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if constexpr (complete_immediately) {
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// HACK! HACK!! HACK!!!
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//
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// This resolves an issue with loading the particular copy of Spindizzy Worlds
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// I am testing against.
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//
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// TODO: DO NOT PUBLISH THIS.
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//
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// This is committed solely so that I can continue researching the real, underlying
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// issue across machines. It would not be acceptable to me to ship this.
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// (and the printf is another reminder-to-self)
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if(width_ == 8 && height_ == 32) {
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printf("Accelerating %d x %d\n", width_, height_);
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while(get_status() & 0x4000) {
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advance_dma<false>();
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}
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return true;
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}
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}
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if(line_mode_) {
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not_zero_flag_ = false;
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// As-yet unimplemented:
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assert(b_data_ == 0xffff);
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//
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// Line mode.
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//
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// Bluffer's guide to line mode:
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//
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// In Bresenham terms, the following registers have been set up:
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//
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// [A modulo] = 4 * (dy - dx)
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// [B modulo] = 4 * dy
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// [A pointer] = 4 * dy - 2 * dx, with the sign flag in BLTCON1 indicating sign.
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//
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// [A data] = 0x8000
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// [Both masks] = 0xffff
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// [A shift] = x1 & 15
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//
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// [B data] = texture
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// [B shift] = bit at which to start the line texture (0 = LSB)
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//
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// [C and D pointers] = word containing the first pixel of the line
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// [C and D modulo] = width of the bitplane in bytes
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//
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// height = number of pixels
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//
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// If ONEDOT of BLTCON1 is set, plot only a single bit per horizontal row.
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//
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// BLTCON1 quadrants are (bits 2–4):
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//
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// 110 -> step in x, x positive, y negative
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// 111 -> step in x, x negative, y negative
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// 101 -> step in x, x negative, y positive
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// 100 -> step in x, x positive, y positive
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//
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// 001 -> step in y, x positive, y negative
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// 011 -> step in y, x negative, y negative
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// 010 -> step in y, x negative, y positive
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// 000 -> step in y, x positive, y positive
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//
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// So that's:
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//
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// * bit 4 = x [=1] or y [=0] major;
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// * bit 3 = 1 => major variable negative; otherwise positive;
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// * bit 2 = 1 => minor variable negative; otherwise positive.
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//
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// Implementation below is heavily based on the documentation found
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// at https://github.com/niklasekstrom/blitter-subpixel-line/blob/master/Drawing%20lines%20using%20the%20Amiga%20blitter.pdf
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//
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//
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// Caveat: I've no idea how the DMA access slots should be laid out for
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// line drawing.
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//
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if(!busy_) {
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error_ = int16_t(pointer_[0] << 1) >> 1; // TODO: what happens if line_sign_ doesn't agree with this?
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draw_ = true;
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busy_ = true;
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has_c_data_ = false;
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}
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bool did_output = false;
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if(draw_) {
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// TODO: patterned lines. Unclear what to do with the bit that comes out of b.
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// Probably extend it to a full word?
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if(!has_c_data_) {
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has_c_data_ = true;
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c_data_ = ram_[pointer_[3] & ram_mask_];
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if constexpr (record_bus) {
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transactions_.emplace_back(Transaction::Type::ReadC, pointer_[3], c_data_);
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}
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return true;
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}
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const uint16_t output =
|
||
apply_minterm<uint16_t>(a_data_ >> shifts_[0], b_data_, c_data_, minterms_);
|
||
ram_[pointer_[3] & ram_mask_] = output;
|
||
not_zero_flag_ |= output;
|
||
draw_ &= !one_dot_;
|
||
has_c_data_ = false;
|
||
did_output = true;
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::WriteFromPipeline, pointer_[3], output);
|
||
}
|
||
}
|
||
|
||
constexpr int LEFT = 1 << 0;
|
||
constexpr int RIGHT = 1 << 1;
|
||
constexpr int UP = 1 << 2;
|
||
constexpr int DOWN = 1 << 3;
|
||
int step = (line_direction_ & 4) ?
|
||
((line_direction_ & 1) ? LEFT : RIGHT) :
|
||
((line_direction_ & 1) ? UP : DOWN);
|
||
|
||
if(error_ < 0) {
|
||
error_ += modulos_[1];
|
||
} else {
|
||
step |=
|
||
(line_direction_ & 4) ?
|
||
((line_direction_ & 2) ? UP : DOWN) :
|
||
((line_direction_ & 2) ? LEFT : RIGHT);
|
||
|
||
error_ += modulos_[0];
|
||
}
|
||
|
||
if(step & LEFT) {
|
||
--shifts_[0];
|
||
if(shifts_[0] == -1) {
|
||
--pointer_[3];
|
||
}
|
||
} else if(step & RIGHT) {
|
||
++shifts_[0];
|
||
if(shifts_[0] == 16) {
|
||
++pointer_[3];
|
||
}
|
||
}
|
||
shifts_[0] &= 15;
|
||
|
||
if(step & UP) {
|
||
pointer_[3] -= modulos_[2];
|
||
draw_ = true;
|
||
} else if(step & DOWN) {
|
||
pointer_[3] += modulos_[2];
|
||
draw_ = true;
|
||
}
|
||
|
||
--height_;
|
||
if(!height_) {
|
||
busy_ = false;
|
||
posit_interrupt(InterruptFlag::Blitter);
|
||
}
|
||
|
||
return did_output;
|
||
} else {
|
||
// Copy mode.
|
||
if(!busy_) {
|
||
sequencer_.begin();
|
||
a32_ = 0;
|
||
b32_ = 0;
|
||
|
||
y_ = 0;
|
||
x_ = 0;
|
||
loop_index_ = -1;
|
||
write_phase_ = WritePhase::Starting;
|
||
not_zero_flag_ = false;
|
||
busy_ = true;
|
||
}
|
||
|
||
const auto next = sequencer_.next();
|
||
|
||
// If this is the start of a new iteration, check for end of line,
|
||
// or of blit, and pick an appropriate mask for A based on location.
|
||
if(next.second != loop_index_) {
|
||
transient_a_mask_ = x_ ? 0xffff : a_mask_[0];
|
||
|
||
// Check whether an entire row was completed in the previous iteration.
|
||
// If so then add modulos. Though this won't capture the move off the
|
||
// final line, so that's handled elsewhere.
|
||
if(!x_ && y_) {
|
||
add_modulos();
|
||
}
|
||
|
||
++x_;
|
||
if(x_ == width_) {
|
||
transient_a_mask_ &= a_mask_[1];
|
||
x_ = 0;
|
||
++y_;
|
||
if(y_ == height_) {
|
||
sequencer_.complete();
|
||
}
|
||
}
|
||
++loop_index_;
|
||
}
|
||
|
||
using Channel = BlitterSequencer::Channel;
|
||
switch(next.first) {
|
||
case Channel::A:
|
||
a_data_ = ram_[pointer_[0] & ram_mask_];
|
||
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::ReadA, pointer_[0], a_data_);
|
||
}
|
||
pointer_[0] += direction_;
|
||
return true;
|
||
case Channel::B:
|
||
b_data_ = ram_[pointer_[1] & ram_mask_];
|
||
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::ReadB, pointer_[1], b_data_);
|
||
}
|
||
pointer_[1] += direction_;
|
||
return true;
|
||
case Channel::C:
|
||
c_data_ = ram_[pointer_[2] & ram_mask_];
|
||
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::ReadC, pointer_[2], c_data_);
|
||
}
|
||
pointer_[2] += direction_;
|
||
return true;
|
||
case Channel::FlushPipeline:
|
||
add_modulos();
|
||
posit_interrupt(InterruptFlag::Blitter);
|
||
height_ = 0;
|
||
busy_ = false;
|
||
|
||
if(write_phase_ == WritePhase::Full) {
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::WriteFromPipeline, write_address_, write_value_);
|
||
}
|
||
ram_[write_address_ & ram_mask_] = write_value_;
|
||
write_phase_ = WritePhase::Starting;
|
||
}
|
||
return true;
|
||
|
||
case Channel::None:
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::SkippedSlot);
|
||
}
|
||
return false;
|
||
|
||
case Channel::Write: break;
|
||
}
|
||
|
||
a32_ = (a32_ << 16) | (a_data_ & transient_a_mask_);
|
||
b32_ = (b32_ << 16) | b_data_;
|
||
|
||
uint16_t a, b;
|
||
|
||
// The barrel shifter shifts to the right in ascending address mode,
|
||
// but to the left otherwise.
|
||
if(!one_dot_) {
|
||
a = uint16_t(a32_ >> shifts_[0]);
|
||
b = uint16_t(b32_ >> shifts_[1]);
|
||
} else {
|
||
// TODO: there must be a neater solution than this.
|
||
a = uint16_t(
|
||
(a32_ << shifts_[0]) |
|
||
(a32_ >> (32 - shifts_[0]))
|
||
);
|
||
|
||
b = uint16_t(
|
||
(b32_ << shifts_[1]) |
|
||
(b32_ >> (32 - shifts_[1]))
|
||
);
|
||
}
|
||
|
||
uint16_t output =
|
||
apply_minterm<uint16_t>(
|
||
a,
|
||
b,
|
||
c_data_,
|
||
minterms_);
|
||
|
||
if(exclusive_fill_ || inclusive_fill_) {
|
||
// Use the fill tables nibble-by-nibble to figure out the filled word.
|
||
uint16_t fill_output = 0;
|
||
int ongoing_carry = fill_carry_;
|
||
const int type_mask = exclusive_fill_ ? (1 << 5) : 0;
|
||
for(int c = 0; c < 16; c += 4) {
|
||
const int total_index = (output & 0xf) | (ongoing_carry << 4) | type_mask;
|
||
fill_output |= ((fill_values[total_index >> 3] >> ((total_index & 7) * 4)) & 0xf) << c;
|
||
ongoing_carry = (fill_carries[total_index >> 5] >> (total_index & 31)) & 1;
|
||
output >>= 4;
|
||
}
|
||
|
||
output = fill_output;
|
||
fill_carry_ = ongoing_carry;
|
||
}
|
||
|
||
not_zero_flag_ |= output;
|
||
|
||
switch(write_phase_) {
|
||
case WritePhase::Full:
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::WriteFromPipeline, write_address_, write_value_);
|
||
}
|
||
ram_[write_address_ & ram_mask_] = write_value_;
|
||
[[fallthrough]];
|
||
|
||
case WritePhase::Starting:
|
||
write_phase_ = WritePhase::Full;
|
||
write_address_ = pointer_[3];
|
||
write_value_ = output;
|
||
|
||
if constexpr (record_bus) {
|
||
transactions_.emplace_back(Transaction::Type::AddToPipeline, write_address_, write_value_);
|
||
}
|
||
pointer_[3] += direction_;
|
||
return true;
|
||
|
||
default: assert(false);
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
template <bool record_bus>
|
||
std::vector<typename Blitter<record_bus>::Transaction> Blitter<record_bus>::get_and_reset_transactions() {
|
||
std::vector<Transaction> result;
|
||
std::swap(result, transactions_);
|
||
return result;
|
||
}
|
||
|
||
template class Amiga::Blitter<false>;
|
||
template class Amiga::Blitter<true>;
|
||
template bool Amiga::Blitter<true>::advance_dma<true>();
|
||
template bool Amiga::Blitter<true>::advance_dma<false>();
|
||
template bool Amiga::Blitter<false>::advance_dma<true>();
|
||
template bool Amiga::Blitter<false>::advance_dma<false>();
|