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comparison backend.c @ 1506:ded16f3d7eb4 mame_interp

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Super hacky integration of the version of Musashi from MAME
author Michael Pavone <pavone@retrodev.com>
date Wed, 27 Dec 2017 13:46:52 -0800
parents 92e7dafcc0dc
children 2455662378ed
comparison
equal deleted inserted replaced
1471:2e6320d261ff 1506:ded16f3d7eb4
127 return chunk->read_16(offset, context); 127 return chunk->read_16(offset, context);
128 } 128 }
129 return 0xFFFF; 129 return 0xFFFF;
130 } 130 }
131 131
132 void write_word(uint32_t address, uint16_t value, void **mem_pointers, cpu_options *opts, void *context)
133 {
134 memmap_chunk const *chunk = find_map_chunk(address, opts, 0, NULL);
135 if (!chunk) {
136 return;
137 }
138 uint32_t offset = (address - chunk->start) & chunk->mask;
139 if (chunk->flags & MMAP_WRITE) {
140 uint8_t *base;
141 if (chunk->flags & MMAP_PTR_IDX) {
142 base = mem_pointers[chunk->ptr_index];
143 } else {
144 base = chunk->buffer;
145 }
146 if (base) {
147 if ((chunk->flags & MMAP_ONLY_ODD) || (chunk->flags & MMAP_ONLY_EVEN)) {
148 offset /= 2;
149 if (chunk->flags & MMAP_ONLY_EVEN) {
150 value >>= 16;
151 }
152 base[offset] = value;
153 } else {
154 *(uint16_t *)(base + offset) = value;
155 }
156 return;
157 }
158 }
159 if ((!(chunk->flags & MMAP_WRITE) || (chunk->flags & MMAP_FUNC_NULL)) && chunk->write_16) {
160 chunk->write_16(offset, context, value);
161 }
162 }
163
164 uint8_t read_byte(uint32_t address, void **mem_pointers, cpu_options *opts, void *context)
165 {
166 memmap_chunk const *chunk = find_map_chunk(address, opts, 0, NULL);
167 if (!chunk) {
168 return 0xFF;
169 }
170 uint32_t offset = (address - chunk->start) & chunk->mask;
171 if (chunk->flags & MMAP_READ) {
172 uint8_t *base;
173 if (chunk->flags & MMAP_PTR_IDX) {
174 base = mem_pointers[chunk->ptr_index];
175 } else {
176 base = chunk->buffer;
177 }
178 if (base) {
179 uint16_t val;
180 if ((chunk->flags & MMAP_ONLY_ODD) || (chunk->flags & MMAP_ONLY_EVEN)) {
181 offset /= 2;
182 } else if (opts->byte_swap || (chunk->flags & MMAP_BYTESWAP)) {
183 offset ^= 1;
184 }
185 return base[offset];;
186 }
187 }
188 if ((!(chunk->flags & MMAP_READ) || (chunk->flags & MMAP_FUNC_NULL)) && chunk->read_8) {
189 return chunk->read_8(offset, context);
190 }
191 return 0xFF;
192 }
193
194 void write_byte(uint32_t address, uint8_t value, void **mem_pointers, cpu_options *opts, void *context)
195 {
196 memmap_chunk const *chunk = find_map_chunk(address, opts, 0, NULL);
197 if (!chunk) {
198 return;
199 }
200 uint32_t offset = (address - chunk->start) & chunk->mask;
201 if (chunk->flags & MMAP_WRITE) {
202 uint8_t *base;
203 if (chunk->flags & MMAP_PTR_IDX) {
204 base = mem_pointers[chunk->ptr_index];
205 } else {
206 base = chunk->buffer;
207 }
208 if (base) {
209 if ((chunk->flags & MMAP_ONLY_ODD) || (chunk->flags & MMAP_ONLY_EVEN)) {
210
211 if (chunk->flags & MMAP_ONLY_EVEN) {
212 if (offset & 1) {
213 return;
214 }
215 } else {
216 if (!(offset & 1)) {
217 return;
218 }
219 }
220 offset /= 2;
221
222 } else if (opts->byte_swap || (chunk->flags & MMAP_BYTESWAP)) {
223 offset ^= 1;
224 }
225 base[offset] = value;
226 return;
227 }
228 }
229 if ((!(chunk->flags & MMAP_WRITE) || (chunk->flags & MMAP_FUNC_NULL)) && chunk->write_8) {
230 chunk->write_8(offset, context, value);
231 }
232 }
233
132 uint32_t chunk_size(cpu_options *opts, memmap_chunk const *chunk) 234 uint32_t chunk_size(cpu_options *opts, memmap_chunk const *chunk)
133 { 235 {
134 if (chunk->mask == opts->address_mask) { 236 if (chunk->mask == opts->address_mask) {
135 return chunk->end - chunk->start; 237 return chunk->end - chunk->start;
136 } else { 238 } else {