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Use 32 bit rather than 16 bit ints for loop vars. No risk of overflow and is actually faster.
author Daniel O'Connor <darius@dons.net.au>
date Thu, 27 Feb 2025 15:24:17 +1030
parents babdb5376356
children
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29:babdb5376356 30:92fdf2ef995d
203 // Check it is not too short 203 // Check it is not too short
204 if (shapesamples < 2) { 204 if (shapesamples < 2) {
205 printf("Pulse too short (%lu < %d)\n", shapesamples, 2); 205 printf("Pulse too short (%lu < %d)\n", shapesamples, 2);
206 return 0; 206 return 0;
207 } 207 }
208 // Or too long (will overflow for loop variable)
209 if (qtoi(shapesamples) > 65535) {
210 printf("Shape too long (%u > %d)\n", qtoi(shapesamples), 65535);
211 return 0;
212 }
213 208
214 // Setup interp 0 lane 0 to generate index into shape table 209 // Setup interp 0 lane 0 to generate index into shape table
215 // Mask start is 0 because we use 8 bit samples 210 // Mask start is 0 because we use 8 bit samples
216 cfg = interp_default_config(); 211 cfg = interp_default_config();
217 interp_config_set_shift(&cfg, QBITS); 212 interp_config_set_shift(&cfg, QBITS);
245 240
246 memset(pulse_data, 0, datalen); 241 memset(pulse_data, 0, datalen);
247 memset(pulse_ctrl, 0, datalen); 242 memset(pulse_ctrl, 0, datalen);
248 idx = 0; 243 idx = 0;
249 #if 0 244 #if 0
250 for (uint16_t i = 0; i < 255 * 200; i++) 245 for (uint32_t i = 0; i < 255 * 200; i++)
251 data[idx++] = i / 200; 246 data[idx++] = i / 200;
252 247
253 printf("Dummy done\n"); 248 printf("Dummy done\n");
254 return idx; 249 return idx;
255 #endif 250 #endif
268 data[idx++] = 0; 263 data[idx++] = 0;
269 data[idx++] = 255; 264 data[idx++] = 255;
270 #endif 265 #endif
271 266
272 // Up slew 267 // Up slew
273 for (uint16_t i = 0; i < slew1; i++) { 268 for (uint32_t i = 0; i < slew1; i++) {
274 data[idx++] = qtoi(qdiv(qmul(qint(dcofs), qint(i)), qint(slew1))); 269 data[idx++] = qtoi(qdiv(qmul(qint(dcofs), qint(i)), qint(slew1)));
275 } 270 }
276 for (uint16_t c = 0; c < ncode; c++) { 271 for (uint32_t c = 0; c < ncode; c++) {
277 if (c == 0) 272 if (c == 0)
278 bit1startup = idx; 273 bit1startup = idx;
279 274
280 uint ctrltmp = PACTIVE; 275 uint ctrltmp = PACTIVE;
281 if (code[c] == '0') 276 if (code[c] == '0')
284 // Pulse up 279 // Pulse up
285 if (c == 0) { 280 if (c == 0) {
286 interp0->accum[0] = 0; // Initial offset into shape table 281 interp0->accum[0] = 0; // Initial offset into shape table
287 interp0->base[2] = (uintptr_t)shape; // Start of shape table 282 interp0->base[2] = (uintptr_t)shape; // Start of shape table
288 } 283 }
289 for (uint16_t i = 0; i < shapesamples; i++) { 284 for (uint32_t i = 0; i < shapesamples; i++) {
290 ctrl[idx] = ctrltmp; 285 ctrl[idx] = ctrltmp;
291 if (c == 0) { 286 if (c == 0) {
292 // First code bit 287 // First code bit
293 // Get sample pair 288 // Get sample pair
294 uint8_t *sample_pair = (uint8_t *) interp0->peek[2]; 289 uint8_t *sample_pair = (uint8_t *) interp0->peek[2];
309 bit1stopup = idx - 1; 304 bit1stopup = idx - 1;
310 305
311 // Pulse down 306 // Pulse down
312 // Since the pulse is symmetrical just copy the up slope in reverse 307 // Since the pulse is symmetrical just copy the up slope in reverse
313 // XXX: if we had asymmetrical predistortion this wouldn't be true 308 // XXX: if we had asymmetrical predistortion this wouldn't be true
314 for (uint16_t i = 0; i < shapesamples; i++) { 309 for (uint32_t i = 0; i < shapesamples; i++) {
315 // Could replace this with a separate loop to poke it into place 310 // Could replace this with a separate loop to poke it into place
316 // Similarly for TR switch when implemented 311 // Similarly for TR switch when implemented
317 if (i == 0 && c == 0) 312 if (i == 0 && c == 0)
318 ctrl[idx] = ctrltmp | SENSE1; 313 ctrl[idx] = ctrltmp | SENSE1;
319 else 314 else
321 data[idx++] = data[bit1stopup - i]; 316 data[idx++] = data[bit1stopup - i];
322 } 317 }
323 318
324 // Code gap 319 // Code gap
325 if (c < ncode - 1) 320 if (c < ncode - 1)
326 for (uint16_t i = 0; i < codegap; i++) { 321 for (uint32_t i = 0; i < codegap; i++) {
327 ctrl[idx] = ctrltmp; 322 ctrl[idx] = ctrltmp;
328 data[idx++] = dcofs; 323 data[idx++] = dcofs;
329 } 324 }
330 } 325 }
331 326
332 // Down slew 327 // Down slew
333 for (uint16_t i = 0; i < slew2 + 1; i++) { 328 for (uint32_t i = 0; i < slew2 + 1; i++) {
334 data[idx++] = qtoi(qdiv(qmul(qint(dcofs), qint(slew2 - i)), qint(slew2))); 329 data[idx++] = qtoi(qdiv(qmul(qint(dcofs), qint(slew2 - i)), qint(slew2)));
335 } 330 }
336 331
337 data[idx++] = 0; 332 data[idx++] = 0;
338 ctrl[idx] = 0; 333 ctrl[idx] = 0;