pub unsafe fn shift_left_avx2<const OR_ASSIGN: bool>(
bits: &mut [u64],
rhs: usize,
)Examples found in repository?
crates/competitive/src/data_structure/bitset.rs (line 391)
366 fn shift_left<const OR_ASSIGN: bool>(&mut self, rhs: usize) {
367 if rhs == 0 {
368 return;
369 }
370 if rhs >= self.size {
371 if !OR_ASSIGN {
372 self.reset();
373 }
374 return;
375 }
376 #[cfg(target_arch = "x86_64")]
377 if self.bits.len() >= SIMD_MIN_BLOCKS {
378 if avx512_enabled()
379 && is_x86_feature_detected!("avx512f")
380 && is_x86_feature_detected!("avx512vbmi2")
381 {
382 // SAFETY: blocks are aligned and feature detection checked AVX-512F and VBMI2.
383 unsafe { simd::shift_left_avx512::<OR_ASSIGN>(&mut self.bits, rhs) };
384 if self.size & 511 != 0 {
385 self.trim();
386 }
387 return;
388 }
389 if is_x86_feature_detected!("avx2") {
390 // SAFETY: feature detection checked AVX2 support.
391 unsafe { simd::shift_left_avx2::<OR_ASSIGN>(self.words_mut(), rhs) };
392 if self.size & 63 != 0 {
393 self.trim();
394 }
395 return;
396 }
397 }
398
399 let bits = self.words_mut();
400 let word_shift = rhs >> 6;
401 let bit_shift = rhs & 63;
402 if bit_shift == 0 {
403 for i in (0..bits.len() - word_shift).rev() {
404 if OR_ASSIGN {
405 bits[i + word_shift] |= bits[i];
406 } else {
407 bits[i + word_shift] = bits[i];
408 }
409 }
410 } else {
411 for i in (1..bits.len() - word_shift).rev() {
412 let value = (bits[i] << bit_shift) | (bits[i - 1] >> (64 - bit_shift));
413 if OR_ASSIGN {
414 bits[i + word_shift] |= value;
415 } else {
416 bits[i + word_shift] = value;
417 }
418 }
419 if OR_ASSIGN {
420 bits[word_shift] |= bits[0] << bit_shift;
421 } else {
422 bits[word_shift] = bits[0] << bit_shift;
423 }
424 }
425 if !OR_ASSIGN {
426 bits[..word_shift].fill(0);
427 }
428 if self.size & 63 != 0 {
429 self.trim();
430 }
431 }