core/num/
uint_macros.rs

1macro_rules! uint_impl {
2    (
3        Self = $SelfT:ty,
4        ActualT = $ActualT:ident,
5        SignedT = $SignedT:ident,
6
7        // These are all for use *only* in doc comments.
8        // As such, they're all passed as literals -- passing them as a string
9        // literal is fine if they need to be multiple code tokens.
10        // In non-comments, use the associated constants rather than these.
11        BITS = $BITS:literal,
12        BITS_MINUS_ONE = $BITS_MINUS_ONE:literal,
13        MAX = $MaxV:literal,
14        rot = $rot:literal,
15        rot_op = $rot_op:literal,
16        rot_result = $rot_result:literal,
17        swap_op = $swap_op:literal,
18        swapped = $swapped:literal,
19        reversed = $reversed:literal,
20        le_bytes = $le_bytes:literal,
21        be_bytes = $be_bytes:literal,
22        to_xe_bytes_doc = $to_xe_bytes_doc:expr,
23        from_xe_bytes_doc = $from_xe_bytes_doc:expr,
24        bound_condition = $bound_condition:literal,
25    ) => {
26        /// The smallest value that can be represented by this integer type.
27        ///
28        /// # Examples
29        ///
30        /// ```
31        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN, 0);")]
32        /// ```
33        #[stable(feature = "assoc_int_consts", since = "1.43.0")]
34        pub const MIN: Self = 0;
35
36        /// The largest value that can be represented by this integer type
37        #[doc = concat!("(2<sup>", $BITS, "</sup> &minus; 1", $bound_condition, ").")]
38        ///
39        /// # Examples
40        ///
41        /// ```
42        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX, ", stringify!($MaxV), ");")]
43        /// ```
44        #[stable(feature = "assoc_int_consts", since = "1.43.0")]
45        pub const MAX: Self = !0;
46
47        /// The size of this integer type in bits.
48        ///
49        /// # Examples
50        ///
51        /// ```
52        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::BITS, ", stringify!($BITS), ");")]
53        /// ```
54        #[stable(feature = "int_bits_const", since = "1.53.0")]
55        pub const BITS: u32 = Self::MAX.count_ones();
56
57        /// Returns the number of ones in the binary representation of `self`.
58        ///
59        /// # Examples
60        ///
61        /// ```
62        #[doc = concat!("let n = 0b01001100", stringify!($SelfT), ";")]
63        /// assert_eq!(n.count_ones(), 3);
64        ///
65        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
66        #[doc = concat!("assert_eq!(max.count_ones(), ", stringify!($BITS), ");")]
67        ///
68        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
69        /// assert_eq!(zero.count_ones(), 0);
70        /// ```
71        #[stable(feature = "rust1", since = "1.0.0")]
72        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
73        #[doc(alias = "popcount")]
74        #[doc(alias = "popcnt")]
75        #[must_use = "this returns the result of the operation, \
76                      without modifying the original"]
77        #[inline(always)]
78        pub const fn count_ones(self) -> u32 {
79            return intrinsics::ctpop(self);
80        }
81
82        /// Returns the number of zeros in the binary representation of `self`.
83        ///
84        /// # Examples
85        ///
86        /// ```
87        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
88        #[doc = concat!("assert_eq!(zero.count_zeros(), ", stringify!($BITS), ");")]
89        ///
90        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
91        /// assert_eq!(max.count_zeros(), 0);
92        /// ```
93        #[stable(feature = "rust1", since = "1.0.0")]
94        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
95        #[must_use = "this returns the result of the operation, \
96                      without modifying the original"]
97        #[inline(always)]
98        pub const fn count_zeros(self) -> u32 {
99            (!self).count_ones()
100        }
101
102        /// Returns the number of leading zeros in the binary representation of `self`.
103        ///
104        /// Depending on what you're doing with the value, you might also be interested in the
105        /// [`ilog2`] function which returns a consistent number, even if the type widens.
106        ///
107        /// # Examples
108        ///
109        /// ```
110        #[doc = concat!("let n = ", stringify!($SelfT), "::MAX >> 2;")]
111        /// assert_eq!(n.leading_zeros(), 2);
112        ///
113        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
114        #[doc = concat!("assert_eq!(zero.leading_zeros(), ", stringify!($BITS), ");")]
115        ///
116        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
117        /// assert_eq!(max.leading_zeros(), 0);
118        /// ```
119        #[doc = concat!("[`ilog2`]: ", stringify!($SelfT), "::ilog2")]
120        #[stable(feature = "rust1", since = "1.0.0")]
121        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
122        #[must_use = "this returns the result of the operation, \
123                      without modifying the original"]
124        #[inline(always)]
125        pub const fn leading_zeros(self) -> u32 {
126            return intrinsics::ctlz(self as $ActualT);
127        }
128
129        /// Returns the number of trailing zeros in the binary representation
130        /// of `self`.
131        ///
132        /// # Examples
133        ///
134        /// ```
135        #[doc = concat!("let n = 0b0101000", stringify!($SelfT), ";")]
136        /// assert_eq!(n.trailing_zeros(), 3);
137        ///
138        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
139        #[doc = concat!("assert_eq!(zero.trailing_zeros(), ", stringify!($BITS), ");")]
140        ///
141        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
142        #[doc = concat!("assert_eq!(max.trailing_zeros(), 0);")]
143        /// ```
144        #[stable(feature = "rust1", since = "1.0.0")]
145        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
146        #[must_use = "this returns the result of the operation, \
147                      without modifying the original"]
148        #[inline(always)]
149        pub const fn trailing_zeros(self) -> u32 {
150            return intrinsics::cttz(self);
151        }
152
153        /// Returns the number of leading ones in the binary representation of `self`.
154        ///
155        /// # Examples
156        ///
157        /// ```
158        #[doc = concat!("let n = !(", stringify!($SelfT), "::MAX >> 2);")]
159        /// assert_eq!(n.leading_ones(), 2);
160        ///
161        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
162        /// assert_eq!(zero.leading_ones(), 0);
163        ///
164        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
165        #[doc = concat!("assert_eq!(max.leading_ones(), ", stringify!($BITS), ");")]
166        /// ```
167        #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
168        #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
169        #[must_use = "this returns the result of the operation, \
170                      without modifying the original"]
171        #[inline(always)]
172        pub const fn leading_ones(self) -> u32 {
173            (!self).leading_zeros()
174        }
175
176        /// Returns the number of trailing ones in the binary representation
177        /// of `self`.
178        ///
179        /// # Examples
180        ///
181        /// ```
182        #[doc = concat!("let n = 0b1010111", stringify!($SelfT), ";")]
183        /// assert_eq!(n.trailing_ones(), 3);
184        ///
185        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
186        /// assert_eq!(zero.trailing_ones(), 0);
187        ///
188        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
189        #[doc = concat!("assert_eq!(max.trailing_ones(), ", stringify!($BITS), ");")]
190        /// ```
191        #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
192        #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
193        #[must_use = "this returns the result of the operation, \
194                      without modifying the original"]
195        #[inline(always)]
196        pub const fn trailing_ones(self) -> u32 {
197            (!self).trailing_zeros()
198        }
199
200        /// Returns the minimum number of bits required to represent `self`.
201        ///
202        /// This method returns zero if `self` is zero.
203        ///
204        /// # Examples
205        ///
206        /// ```
207        /// #![feature(uint_bit_width)]
208        ///
209        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".bit_width(), 0);")]
210        #[doc = concat!("assert_eq!(0b111_", stringify!($SelfT), ".bit_width(), 3);")]
211        #[doc = concat!("assert_eq!(0b1110_", stringify!($SelfT), ".bit_width(), 4);")]
212        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.bit_width(), ", stringify!($BITS), ");")]
213        /// ```
214        #[unstable(feature = "uint_bit_width", issue = "142326")]
215        #[must_use = "this returns the result of the operation, \
216                      without modifying the original"]
217        #[inline(always)]
218        pub const fn bit_width(self) -> u32 {
219            Self::BITS - self.leading_zeros()
220        }
221
222        /// Returns `self` with only the most significant bit set, or `0` if
223        /// the input is `0`.
224        ///
225        /// # Examples
226        ///
227        /// ```
228        /// #![feature(isolate_most_least_significant_one)]
229        ///
230        #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
231        ///
232        /// assert_eq!(n.isolate_highest_one(), 0b_01000000);
233        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_highest_one(), 0);")]
234        /// ```
235        #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
236        #[must_use = "this returns the result of the operation, \
237                      without modifying the original"]
238        #[inline(always)]
239        pub const fn isolate_highest_one(self) -> Self {
240            self & (((1 as $SelfT) << (<$SelfT>::BITS - 1)).wrapping_shr(self.leading_zeros()))
241        }
242
243        /// Returns `self` with only the least significant bit set, or `0` if
244        /// the input is `0`.
245        ///
246        /// # Examples
247        ///
248        /// ```
249        /// #![feature(isolate_most_least_significant_one)]
250        ///
251        #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
252        ///
253        /// assert_eq!(n.isolate_lowest_one(), 0b_00000100);
254        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_lowest_one(), 0);")]
255        /// ```
256        #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
257        #[must_use = "this returns the result of the operation, \
258                      without modifying the original"]
259        #[inline(always)]
260        pub const fn isolate_lowest_one(self) -> Self {
261            self & self.wrapping_neg()
262        }
263
264        /// Returns the bit pattern of `self` reinterpreted as a signed integer of the same size.
265        ///
266        /// This produces the same result as an `as` cast, but ensures that the bit-width remains
267        /// the same.
268        ///
269        /// # Examples
270        ///
271        /// ```
272        #[doc = concat!("let n = ", stringify!($SelfT), "::MAX;")]
273        ///
274        #[doc = concat!("assert_eq!(n.cast_signed(), -1", stringify!($SignedT), ");")]
275        /// ```
276        #[stable(feature = "integer_sign_cast", since = "1.87.0")]
277        #[rustc_const_stable(feature = "integer_sign_cast", since = "1.87.0")]
278        #[must_use = "this returns the result of the operation, \
279                      without modifying the original"]
280        #[inline(always)]
281        pub const fn cast_signed(self) -> $SignedT {
282            self as $SignedT
283        }
284
285        /// Shifts the bits to the left by a specified amount, `n`,
286        /// wrapping the truncated bits to the end of the resulting integer.
287        ///
288        /// Please note this isn't the same operation as the `<<` shifting operator!
289        ///
290        /// # Examples
291        ///
292        /// ```
293        #[doc = concat!("let n = ", $rot_op, stringify!($SelfT), ";")]
294        #[doc = concat!("let m = ", $rot_result, ";")]
295        ///
296        #[doc = concat!("assert_eq!(n.rotate_left(", $rot, "), m);")]
297        /// ```
298        #[stable(feature = "rust1", since = "1.0.0")]
299        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
300        #[must_use = "this returns the result of the operation, \
301                      without modifying the original"]
302        #[inline(always)]
303        pub const fn rotate_left(self, n: u32) -> Self {
304            return intrinsics::rotate_left(self, n);
305        }
306
307        /// Shifts the bits to the right by a specified amount, `n`,
308        /// wrapping the truncated bits to the beginning of the resulting
309        /// integer.
310        ///
311        /// Please note this isn't the same operation as the `>>` shifting operator!
312        ///
313        /// # Examples
314        ///
315        /// ```
316        #[doc = concat!("let n = ", $rot_result, stringify!($SelfT), ";")]
317        #[doc = concat!("let m = ", $rot_op, ";")]
318        ///
319        #[doc = concat!("assert_eq!(n.rotate_right(", $rot, "), m);")]
320        /// ```
321        #[stable(feature = "rust1", since = "1.0.0")]
322        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
323        #[must_use = "this returns the result of the operation, \
324                      without modifying the original"]
325        #[inline(always)]
326        pub const fn rotate_right(self, n: u32) -> Self {
327            return intrinsics::rotate_right(self, n);
328        }
329
330        /// Reverses the byte order of the integer.
331        ///
332        /// # Examples
333        ///
334        /// ```
335        #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")]
336        /// let m = n.swap_bytes();
337        ///
338        #[doc = concat!("assert_eq!(m, ", $swapped, ");")]
339        /// ```
340        #[stable(feature = "rust1", since = "1.0.0")]
341        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
342        #[must_use = "this returns the result of the operation, \
343                      without modifying the original"]
344        #[inline(always)]
345        pub const fn swap_bytes(self) -> Self {
346            intrinsics::bswap(self as $ActualT) as Self
347        }
348
349        /// Reverses the order of bits in the integer. The least significant bit becomes the most significant bit,
350        ///                 second least-significant bit becomes second most-significant bit, etc.
351        ///
352        /// # Examples
353        ///
354        /// ```
355        #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")]
356        /// let m = n.reverse_bits();
357        ///
358        #[doc = concat!("assert_eq!(m, ", $reversed, ");")]
359        #[doc = concat!("assert_eq!(0, 0", stringify!($SelfT), ".reverse_bits());")]
360        /// ```
361        #[stable(feature = "reverse_bits", since = "1.37.0")]
362        #[rustc_const_stable(feature = "reverse_bits", since = "1.37.0")]
363        #[must_use = "this returns the result of the operation, \
364                      without modifying the original"]
365        #[inline(always)]
366        pub const fn reverse_bits(self) -> Self {
367            intrinsics::bitreverse(self as $ActualT) as Self
368        }
369
370        /// Converts an integer from big endian to the target's endianness.
371        ///
372        /// On big endian this is a no-op. On little endian the bytes are
373        /// swapped.
374        ///
375        /// # Examples
376        ///
377        /// ```
378        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
379        ///
380        /// if cfg!(target_endian = "big") {
381        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_be(n), n)")]
382        /// } else {
383        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_be(n), n.swap_bytes())")]
384        /// }
385        /// ```
386        #[stable(feature = "rust1", since = "1.0.0")]
387        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
388        #[must_use]
389        #[inline(always)]
390        pub const fn from_be(x: Self) -> Self {
391            #[cfg(target_endian = "big")]
392            {
393                x
394            }
395            #[cfg(not(target_endian = "big"))]
396            {
397                x.swap_bytes()
398            }
399        }
400
401        /// Converts an integer from little endian to the target's endianness.
402        ///
403        /// On little endian this is a no-op. On big endian the bytes are
404        /// swapped.
405        ///
406        /// # Examples
407        ///
408        /// ```
409        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
410        ///
411        /// if cfg!(target_endian = "little") {
412        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_le(n), n)")]
413        /// } else {
414        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_le(n), n.swap_bytes())")]
415        /// }
416        /// ```
417        #[stable(feature = "rust1", since = "1.0.0")]
418        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
419        #[must_use]
420        #[inline(always)]
421        pub const fn from_le(x: Self) -> Self {
422            #[cfg(target_endian = "little")]
423            {
424                x
425            }
426            #[cfg(not(target_endian = "little"))]
427            {
428                x.swap_bytes()
429            }
430        }
431
432        /// Converts `self` to big endian from the target's endianness.
433        ///
434        /// On big endian this is a no-op. On little endian the bytes are
435        /// swapped.
436        ///
437        /// # Examples
438        ///
439        /// ```
440        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
441        ///
442        /// if cfg!(target_endian = "big") {
443        ///     assert_eq!(n.to_be(), n)
444        /// } else {
445        ///     assert_eq!(n.to_be(), n.swap_bytes())
446        /// }
447        /// ```
448        #[stable(feature = "rust1", since = "1.0.0")]
449        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
450        #[must_use = "this returns the result of the operation, \
451                      without modifying the original"]
452        #[inline(always)]
453        pub const fn to_be(self) -> Self { // or not to be?
454            #[cfg(target_endian = "big")]
455            {
456                self
457            }
458            #[cfg(not(target_endian = "big"))]
459            {
460                self.swap_bytes()
461            }
462        }
463
464        /// Converts `self` to little endian from the target's endianness.
465        ///
466        /// On little endian this is a no-op. On big endian the bytes are
467        /// swapped.
468        ///
469        /// # Examples
470        ///
471        /// ```
472        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
473        ///
474        /// if cfg!(target_endian = "little") {
475        ///     assert_eq!(n.to_le(), n)
476        /// } else {
477        ///     assert_eq!(n.to_le(), n.swap_bytes())
478        /// }
479        /// ```
480        #[stable(feature = "rust1", since = "1.0.0")]
481        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
482        #[must_use = "this returns the result of the operation, \
483                      without modifying the original"]
484        #[inline(always)]
485        pub const fn to_le(self) -> Self {
486            #[cfg(target_endian = "little")]
487            {
488                self
489            }
490            #[cfg(not(target_endian = "little"))]
491            {
492                self.swap_bytes()
493            }
494        }
495
496        /// Checked integer addition. Computes `self + rhs`, returning `None`
497        /// if overflow occurred.
498        ///
499        /// # Examples
500        ///
501        /// ```
502        #[doc = concat!(
503            "assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(1), ",
504            "Some(", stringify!($SelfT), "::MAX - 1));"
505        )]
506        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(3), None);")]
507        /// ```
508        #[stable(feature = "rust1", since = "1.0.0")]
509        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
510        #[must_use = "this returns the result of the operation, \
511                      without modifying the original"]
512        #[inline]
513        pub const fn checked_add(self, rhs: Self) -> Option<Self> {
514            // This used to use `overflowing_add`, but that means it ends up being
515            // a `wrapping_add`, losing some optimization opportunities. Notably,
516            // phrasing it this way helps `.checked_add(1)` optimize to a check
517            // against `MAX` and a `add nuw`.
518            // Per <https://github.com/rust-lang/rust/pull/124114#issuecomment-2066173305>,
519            // LLVM is happy to re-form the intrinsic later if useful.
520
521            if intrinsics::unlikely(intrinsics::add_with_overflow(self, rhs).1) {
522                None
523            } else {
524                // SAFETY: Just checked it doesn't overflow
525                Some(unsafe { intrinsics::unchecked_add(self, rhs) })
526            }
527        }
528
529        /// Strict integer addition. Computes `self + rhs`, panicking
530        /// if overflow occurred.
531        ///
532        /// # Panics
533        ///
534        /// ## Overflow behavior
535        ///
536        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
537        ///
538        /// # Examples
539        ///
540        /// ```
541        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).strict_add(1), ", stringify!($SelfT), "::MAX - 1);")]
542        /// ```
543        ///
544        /// The following panics because of overflow:
545        ///
546        /// ```should_panic
547        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add(3);")]
548        /// ```
549        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
550        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
551        #[must_use = "this returns the result of the operation, \
552                      without modifying the original"]
553        #[inline]
554        #[track_caller]
555        pub const fn strict_add(self, rhs: Self) -> Self {
556            let (a, b) = self.overflowing_add(rhs);
557            if b { overflow_panic::add() } else { a }
558        }
559
560        /// Unchecked integer addition. Computes `self + rhs`, assuming overflow
561        /// cannot occur.
562        ///
563        /// Calling `x.unchecked_add(y)` is semantically equivalent to calling
564        /// `x.`[`checked_add`]`(y).`[`unwrap_unchecked`]`()`.
565        ///
566        /// If you're just trying to avoid the panic in debug mode, then **do not**
567        /// use this.  Instead, you're looking for [`wrapping_add`].
568        ///
569        /// # Safety
570        ///
571        /// This results in undefined behavior when
572        #[doc = concat!("`self + rhs > ", stringify!($SelfT), "::MAX` or `self + rhs < ", stringify!($SelfT), "::MIN`,")]
573        /// i.e. when [`checked_add`] would return `None`.
574        ///
575        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
576        #[doc = concat!("[`checked_add`]: ", stringify!($SelfT), "::checked_add")]
577        #[doc = concat!("[`wrapping_add`]: ", stringify!($SelfT), "::wrapping_add")]
578        #[stable(feature = "unchecked_math", since = "1.79.0")]
579        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
580        #[must_use = "this returns the result of the operation, \
581                      without modifying the original"]
582        #[inline(always)]
583        #[track_caller]
584        pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
585            assert_unsafe_precondition!(
586                check_language_ub,
587                concat!(stringify!($SelfT), "::unchecked_add cannot overflow"),
588                (
589                    lhs: $SelfT = self,
590                    rhs: $SelfT = rhs,
591                ) => !lhs.overflowing_add(rhs).1,
592            );
593
594            // SAFETY: this is guaranteed to be safe by the caller.
595            unsafe {
596                intrinsics::unchecked_add(self, rhs)
597            }
598        }
599
600        /// Checked addition with a signed integer. Computes `self + rhs`,
601        /// returning `None` if overflow occurred.
602        ///
603        /// # Examples
604        ///
605        /// ```
606        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(2), Some(3));")]
607        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(-2), None);")]
608        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_signed(3), None);")]
609        /// ```
610        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
611        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
612        #[must_use = "this returns the result of the operation, \
613                      without modifying the original"]
614        #[inline]
615        pub const fn checked_add_signed(self, rhs: $SignedT) -> Option<Self> {
616            let (a, b) = self.overflowing_add_signed(rhs);
617            if intrinsics::unlikely(b) { None } else { Some(a) }
618        }
619
620        /// Strict addition with a signed integer. Computes `self + rhs`,
621        /// panicking if overflow occurred.
622        ///
623        /// # Panics
624        ///
625        /// ## Overflow behavior
626        ///
627        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
628        ///
629        /// # Examples
630        ///
631        /// ```
632        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_add_signed(2), 3);")]
633        /// ```
634        ///
635        /// The following panic because of overflow:
636        ///
637        /// ```should_panic
638        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_add_signed(-2);")]
639        /// ```
640        ///
641        /// ```should_panic
642        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add_signed(3);")]
643        /// ```
644        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
645        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
646        #[must_use = "this returns the result of the operation, \
647                      without modifying the original"]
648        #[inline]
649        #[track_caller]
650        pub const fn strict_add_signed(self, rhs: $SignedT) -> Self {
651            let (a, b) = self.overflowing_add_signed(rhs);
652            if b { overflow_panic::add() } else { a }
653        }
654
655        /// Checked integer subtraction. Computes `self - rhs`, returning
656        /// `None` if overflow occurred.
657        ///
658        /// # Examples
659        ///
660        /// ```
661        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub(1), Some(0));")]
662        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".checked_sub(1), None);")]
663        /// ```
664        #[stable(feature = "rust1", since = "1.0.0")]
665        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
666        #[must_use = "this returns the result of the operation, \
667                      without modifying the original"]
668        #[inline]
669        pub const fn checked_sub(self, rhs: Self) -> Option<Self> {
670            // Per PR#103299, there's no advantage to the `overflowing` intrinsic
671            // for *unsigned* subtraction and we just emit the manual check anyway.
672            // Thus, rather than using `overflowing_sub` that produces a wrapping
673            // subtraction, check it ourself so we can use an unchecked one.
674
675            if self < rhs {
676                None
677            } else {
678                // SAFETY: just checked this can't overflow
679                Some(unsafe { intrinsics::unchecked_sub(self, rhs) })
680            }
681        }
682
683        /// Strict integer subtraction. Computes `self - rhs`, panicking if
684        /// overflow occurred.
685        ///
686        /// # Panics
687        ///
688        /// ## Overflow behavior
689        ///
690        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
691        ///
692        /// # Examples
693        ///
694        /// ```
695        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_sub(1), 0);")]
696        /// ```
697        ///
698        /// The following panics because of overflow:
699        ///
700        /// ```should_panic
701        #[doc = concat!("let _ = 0", stringify!($SelfT), ".strict_sub(1);")]
702        /// ```
703        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
704        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
705        #[must_use = "this returns the result of the operation, \
706                      without modifying the original"]
707        #[inline]
708        #[track_caller]
709        pub const fn strict_sub(self, rhs: Self) -> Self {
710            let (a, b) = self.overflowing_sub(rhs);
711            if b { overflow_panic::sub() } else { a }
712        }
713
714        /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow
715        /// cannot occur.
716        ///
717        /// Calling `x.unchecked_sub(y)` is semantically equivalent to calling
718        /// `x.`[`checked_sub`]`(y).`[`unwrap_unchecked`]`()`.
719        ///
720        /// If you're just trying to avoid the panic in debug mode, then **do not**
721        /// use this.  Instead, you're looking for [`wrapping_sub`].
722        ///
723        /// If you find yourself writing code like this:
724        ///
725        /// ```
726        /// # let foo = 30_u32;
727        /// # let bar = 20;
728        /// if foo >= bar {
729        ///     // SAFETY: just checked it will not overflow
730        ///     let diff = unsafe { foo.unchecked_sub(bar) };
731        ///     // ... use diff ...
732        /// }
733        /// ```
734        ///
735        /// Consider changing it to
736        ///
737        /// ```
738        /// # let foo = 30_u32;
739        /// # let bar = 20;
740        /// if let Some(diff) = foo.checked_sub(bar) {
741        ///     // ... use diff ...
742        /// }
743        /// ```
744        ///
745        /// As that does exactly the same thing -- including telling the optimizer
746        /// that the subtraction cannot overflow -- but avoids needing `unsafe`.
747        ///
748        /// # Safety
749        ///
750        /// This results in undefined behavior when
751        #[doc = concat!("`self - rhs > ", stringify!($SelfT), "::MAX` or `self - rhs < ", stringify!($SelfT), "::MIN`,")]
752        /// i.e. when [`checked_sub`] would return `None`.
753        ///
754        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
755        #[doc = concat!("[`checked_sub`]: ", stringify!($SelfT), "::checked_sub")]
756        #[doc = concat!("[`wrapping_sub`]: ", stringify!($SelfT), "::wrapping_sub")]
757        #[stable(feature = "unchecked_math", since = "1.79.0")]
758        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
759        #[must_use = "this returns the result of the operation, \
760                      without modifying the original"]
761        #[inline(always)]
762        #[track_caller]
763        pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
764            assert_unsafe_precondition!(
765                check_language_ub,
766                concat!(stringify!($SelfT), "::unchecked_sub cannot overflow"),
767                (
768                    lhs: $SelfT = self,
769                    rhs: $SelfT = rhs,
770                ) => !lhs.overflowing_sub(rhs).1,
771            );
772
773            // SAFETY: this is guaranteed to be safe by the caller.
774            unsafe {
775                intrinsics::unchecked_sub(self, rhs)
776            }
777        }
778
779        /// Checked subtraction with a signed integer. Computes `self - rhs`,
780        /// returning `None` if overflow occurred.
781        ///
782        /// # Examples
783        ///
784        /// ```
785        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_signed(2), None);")]
786        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_signed(-2), Some(3));")]
787        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_sub_signed(-4), None);")]
788        /// ```
789        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
790        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
791        #[must_use = "this returns the result of the operation, \
792                      without modifying the original"]
793        #[inline]
794        pub const fn checked_sub_signed(self, rhs: $SignedT) -> Option<Self> {
795            let (res, overflow) = self.overflowing_sub_signed(rhs);
796
797            if !overflow {
798                Some(res)
799            } else {
800                None
801            }
802        }
803
804        /// Strict subtraction with a signed integer. Computes `self - rhs`,
805        /// panicking if overflow occurred.
806        ///
807        /// # Panics
808        ///
809        /// ## Overflow behavior
810        ///
811        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
812        ///
813        /// # Examples
814        ///
815        /// ```
816        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".strict_sub_signed(2), 1);")]
817        /// ```
818        ///
819        /// The following panic because of overflow:
820        ///
821        /// ```should_panic
822        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_sub_signed(2);")]
823        /// ```
824        ///
825        /// ```should_panic
826        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX).strict_sub_signed(-1);")]
827        /// ```
828        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
829        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
830        #[must_use = "this returns the result of the operation, \
831                      without modifying the original"]
832        #[inline]
833        #[track_caller]
834        pub const fn strict_sub_signed(self, rhs: $SignedT) -> Self {
835            let (a, b) = self.overflowing_sub_signed(rhs);
836            if b { overflow_panic::sub() } else { a }
837        }
838
839        #[doc = concat!(
840            "Checked integer subtraction. Computes `self - rhs` and checks if the result fits into an [`",
841            stringify!($SignedT), "`], returning `None` if overflow occurred."
842        )]
843        ///
844        /// # Examples
845        ///
846        /// ```
847        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_signed_diff(2), Some(8));")]
848        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_signed_diff(10), Some(-8));")]
849        #[doc = concat!(
850            "assert_eq!(",
851            stringify!($SelfT),
852            "::MAX.checked_signed_diff(",
853            stringify!($SignedT),
854            "::MAX as ",
855            stringify!($SelfT),
856            "), None);"
857        )]
858        #[doc = concat!(
859            "assert_eq!((",
860            stringify!($SignedT),
861            "::MAX as ",
862            stringify!($SelfT),
863            ").checked_signed_diff(",
864            stringify!($SelfT),
865            "::MAX), Some(",
866            stringify!($SignedT),
867            "::MIN));"
868        )]
869        #[doc = concat!(
870            "assert_eq!((",
871            stringify!($SignedT),
872            "::MAX as ",
873            stringify!($SelfT),
874            " + 1).checked_signed_diff(0), None);"
875        )]
876        #[doc = concat!(
877            "assert_eq!(",
878            stringify!($SelfT),
879            "::MAX.checked_signed_diff(",
880            stringify!($SelfT),
881            "::MAX), Some(0));"
882        )]
883        /// ```
884        #[stable(feature = "unsigned_signed_diff", since = "CURRENT_RUSTC_VERSION")]
885        #[rustc_const_stable(feature = "unsigned_signed_diff", since = "CURRENT_RUSTC_VERSION")]
886        #[inline]
887        pub const fn checked_signed_diff(self, rhs: Self) -> Option<$SignedT> {
888            let res = self.wrapping_sub(rhs) as $SignedT;
889            let overflow = (self >= rhs) == (res < 0);
890
891            if !overflow {
892                Some(res)
893            } else {
894                None
895            }
896        }
897
898        /// Checked integer multiplication. Computes `self * rhs`, returning
899        /// `None` if overflow occurred.
900        ///
901        /// # Examples
902        ///
903        /// ```
904        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_mul(1), Some(5));")]
905        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);")]
906        /// ```
907        #[stable(feature = "rust1", since = "1.0.0")]
908        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
909        #[must_use = "this returns the result of the operation, \
910                      without modifying the original"]
911        #[inline]
912        pub const fn checked_mul(self, rhs: Self) -> Option<Self> {
913            let (a, b) = self.overflowing_mul(rhs);
914            if intrinsics::unlikely(b) { None } else { Some(a) }
915        }
916
917        /// Strict integer multiplication. Computes `self * rhs`, panicking if
918        /// overflow occurred.
919        ///
920        /// # Panics
921        ///
922        /// ## Overflow behavior
923        ///
924        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
925        ///
926        /// # Examples
927        ///
928        /// ```
929        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_mul(1), 5);")]
930        /// ```
931        ///
932        /// The following panics because of overflow:
933        ///
934        /// ``` should_panic
935        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_mul(2);")]
936        /// ```
937        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
938        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
939        #[must_use = "this returns the result of the operation, \
940                      without modifying the original"]
941        #[inline]
942        #[track_caller]
943        pub const fn strict_mul(self, rhs: Self) -> Self {
944            let (a, b) = self.overflowing_mul(rhs);
945            if b { overflow_panic::mul() } else { a }
946        }
947
948        /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow
949        /// cannot occur.
950        ///
951        /// Calling `x.unchecked_mul(y)` is semantically equivalent to calling
952        /// `x.`[`checked_mul`]`(y).`[`unwrap_unchecked`]`()`.
953        ///
954        /// If you're just trying to avoid the panic in debug mode, then **do not**
955        /// use this.  Instead, you're looking for [`wrapping_mul`].
956        ///
957        /// # Safety
958        ///
959        /// This results in undefined behavior when
960        #[doc = concat!("`self * rhs > ", stringify!($SelfT), "::MAX` or `self * rhs < ", stringify!($SelfT), "::MIN`,")]
961        /// i.e. when [`checked_mul`] would return `None`.
962        ///
963        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
964        #[doc = concat!("[`checked_mul`]: ", stringify!($SelfT), "::checked_mul")]
965        #[doc = concat!("[`wrapping_mul`]: ", stringify!($SelfT), "::wrapping_mul")]
966        #[stable(feature = "unchecked_math", since = "1.79.0")]
967        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
968        #[must_use = "this returns the result of the operation, \
969                      without modifying the original"]
970        #[inline(always)]
971        #[track_caller]
972        pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
973            assert_unsafe_precondition!(
974                check_language_ub,
975                concat!(stringify!($SelfT), "::unchecked_mul cannot overflow"),
976                (
977                    lhs: $SelfT = self,
978                    rhs: $SelfT = rhs,
979                ) => !lhs.overflowing_mul(rhs).1,
980            );
981
982            // SAFETY: this is guaranteed to be safe by the caller.
983            unsafe {
984                intrinsics::unchecked_mul(self, rhs)
985            }
986        }
987
988        /// Checked integer division. Computes `self / rhs`, returning `None`
989        /// if `rhs == 0`.
990        ///
991        /// # Examples
992        ///
993        /// ```
994        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".checked_div(2), Some(64));")]
995        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_div(0), None);")]
996        /// ```
997        #[stable(feature = "rust1", since = "1.0.0")]
998        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
999        #[must_use = "this returns the result of the operation, \
1000                      without modifying the original"]
1001        #[inline]
1002        pub const fn checked_div(self, rhs: Self) -> Option<Self> {
1003            if intrinsics::unlikely(rhs == 0) {
1004                None
1005            } else {
1006                // SAFETY: div by zero has been checked above and unsigned types have no other
1007                // failure modes for division
1008                Some(unsafe { intrinsics::unchecked_div(self, rhs) })
1009            }
1010        }
1011
1012        /// Strict integer division. Computes `self / rhs`.
1013        ///
1014        /// Strict division on unsigned types is just normal division. There's no
1015        /// way overflow could ever happen. This function exists so that all
1016        /// operations are accounted for in the strict operations.
1017        ///
1018        /// # Panics
1019        ///
1020        /// This function will panic if `rhs` is zero.
1021        ///
1022        /// # Examples
1023        ///
1024        /// ```
1025        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_div(10), 10);")]
1026        /// ```
1027        ///
1028        /// The following panics because of division by zero:
1029        ///
1030        /// ```should_panic
1031        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div(0);")]
1032        /// ```
1033        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1034        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1035        #[must_use = "this returns the result of the operation, \
1036                      without modifying the original"]
1037        #[inline(always)]
1038        #[track_caller]
1039        pub const fn strict_div(self, rhs: Self) -> Self {
1040            self / rhs
1041        }
1042
1043        /// Checked Euclidean division. Computes `self.div_euclid(rhs)`, returning `None`
1044        /// if `rhs == 0`.
1045        ///
1046        /// # Examples
1047        ///
1048        /// ```
1049        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".checked_div_euclid(2), Some(64));")]
1050        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_div_euclid(0), None);")]
1051        /// ```
1052        #[stable(feature = "euclidean_division", since = "1.38.0")]
1053        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1054        #[must_use = "this returns the result of the operation, \
1055                      without modifying the original"]
1056        #[inline]
1057        pub const fn checked_div_euclid(self, rhs: Self) -> Option<Self> {
1058            if intrinsics::unlikely(rhs == 0) {
1059                None
1060            } else {
1061                Some(self.div_euclid(rhs))
1062            }
1063        }
1064
1065        /// Strict Euclidean division. Computes `self.div_euclid(rhs)`.
1066        ///
1067        /// Strict division on unsigned types is just normal division. There's no
1068        /// way overflow could ever happen. This function exists so that all
1069        /// operations are accounted for in the strict operations. Since, for the
1070        /// positive integers, all common definitions of division are equal, this
1071        /// is exactly equal to `self.strict_div(rhs)`.
1072        ///
1073        /// # Panics
1074        ///
1075        /// This function will panic if `rhs` is zero.
1076        ///
1077        /// # Examples
1078        ///
1079        /// ```
1080        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_div_euclid(10), 10);")]
1081        /// ```
1082        /// The following panics because of division by zero:
1083        ///
1084        /// ```should_panic
1085        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div_euclid(0);")]
1086        /// ```
1087        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1088        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1089        #[must_use = "this returns the result of the operation, \
1090                      without modifying the original"]
1091        #[inline(always)]
1092        #[track_caller]
1093        pub const fn strict_div_euclid(self, rhs: Self) -> Self {
1094            self / rhs
1095        }
1096
1097        /// Checked integer division without remainder. Computes `self / rhs`,
1098        /// returning `None` if `rhs == 0` or if `self % rhs != 0`.
1099        ///
1100        /// # Examples
1101        ///
1102        /// ```
1103        /// #![feature(exact_div)]
1104        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".checked_exact_div(2), Some(32));")]
1105        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".checked_exact_div(32), Some(2));")]
1106        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".checked_exact_div(0), None);")]
1107        #[doc = concat!("assert_eq!(65", stringify!($SelfT), ".checked_exact_div(2), None);")]
1108        /// ```
1109        #[unstable(
1110            feature = "exact_div",
1111            issue = "139911",
1112        )]
1113        #[must_use = "this returns the result of the operation, \
1114                      without modifying the original"]
1115        #[inline]
1116        pub const fn checked_exact_div(self, rhs: Self) -> Option<Self> {
1117            if intrinsics::unlikely(rhs == 0) {
1118                None
1119            } else {
1120                // SAFETY: division by zero is checked above
1121                unsafe {
1122                    if intrinsics::unlikely(intrinsics::unchecked_rem(self, rhs) != 0) {
1123                        None
1124                    } else {
1125                        Some(intrinsics::exact_div(self, rhs))
1126                    }
1127                }
1128            }
1129        }
1130
1131        /// Checked integer division without remainder. Computes `self / rhs`.
1132        ///
1133        /// # Panics
1134        ///
1135        /// This function will panic  if `rhs == 0` or `self % rhs != 0`.
1136        ///
1137        /// # Examples
1138        ///
1139        /// ```
1140        /// #![feature(exact_div)]
1141        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(2), 32);")]
1142        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(32), 2);")]
1143        /// ```
1144        ///
1145        /// ```should_panic
1146        /// #![feature(exact_div)]
1147        #[doc = concat!("let _ = 65", stringify!($SelfT), ".exact_div(2);")]
1148        /// ```
1149        #[unstable(
1150            feature = "exact_div",
1151            issue = "139911",
1152        )]
1153        #[must_use = "this returns the result of the operation, \
1154                      without modifying the original"]
1155        #[inline]
1156        pub const fn exact_div(self, rhs: Self) -> Self {
1157            match self.checked_exact_div(rhs) {
1158                Some(x) => x,
1159                None => panic!("Failed to divide without remainder"),
1160            }
1161        }
1162
1163        /// Unchecked integer division without remainder. Computes `self / rhs`.
1164        ///
1165        /// # Safety
1166        ///
1167        /// This results in undefined behavior when `rhs == 0` or `self % rhs != 0`,
1168        /// i.e. when [`checked_exact_div`](Self::checked_exact_div) would return `None`.
1169        #[unstable(
1170            feature = "exact_div",
1171            issue = "139911",
1172        )]
1173        #[must_use = "this returns the result of the operation, \
1174                      without modifying the original"]
1175        #[inline]
1176        pub const unsafe fn unchecked_exact_div(self, rhs: Self) -> Self {
1177            assert_unsafe_precondition!(
1178                check_language_ub,
1179                concat!(stringify!($SelfT), "::unchecked_exact_div divide by zero or leave a remainder"),
1180                (
1181                    lhs: $SelfT = self,
1182                    rhs: $SelfT = rhs,
1183                ) => rhs > 0 && lhs % rhs == 0,
1184            );
1185            // SAFETY: Same precondition
1186            unsafe { intrinsics::exact_div(self, rhs) }
1187        }
1188
1189        /// Checked integer remainder. Computes `self % rhs`, returning `None`
1190        /// if `rhs == 0`.
1191        ///
1192        /// # Examples
1193        ///
1194        /// ```
1195        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(2), Some(1));")]
1196        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(0), None);")]
1197        /// ```
1198        #[stable(feature = "wrapping", since = "1.7.0")]
1199        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
1200        #[must_use = "this returns the result of the operation, \
1201                      without modifying the original"]
1202        #[inline]
1203        pub const fn checked_rem(self, rhs: Self) -> Option<Self> {
1204            if intrinsics::unlikely(rhs == 0) {
1205                None
1206            } else {
1207                // SAFETY: div by zero has been checked above and unsigned types have no other
1208                // failure modes for division
1209                Some(unsafe { intrinsics::unchecked_rem(self, rhs) })
1210            }
1211        }
1212
1213        /// Strict integer remainder. Computes `self % rhs`.
1214        ///
1215        /// Strict remainder calculation on unsigned types is just the regular
1216        /// remainder calculation. There's no way overflow could ever happen.
1217        /// This function exists so that all operations are accounted for in the
1218        /// strict operations.
1219        ///
1220        /// # Panics
1221        ///
1222        /// This function will panic if `rhs` is zero.
1223        ///
1224        /// # Examples
1225        ///
1226        /// ```
1227        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_rem(10), 0);")]
1228        /// ```
1229        ///
1230        /// The following panics because of division by zero:
1231        ///
1232        /// ```should_panic
1233        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem(0);")]
1234        /// ```
1235        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1236        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1237        #[must_use = "this returns the result of the operation, \
1238                      without modifying the original"]
1239        #[inline(always)]
1240        #[track_caller]
1241        pub const fn strict_rem(self, rhs: Self) -> Self {
1242            self % rhs
1243        }
1244
1245        /// Checked Euclidean modulo. Computes `self.rem_euclid(rhs)`, returning `None`
1246        /// if `rhs == 0`.
1247        ///
1248        /// # Examples
1249        ///
1250        /// ```
1251        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(2), Some(1));")]
1252        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(0), None);")]
1253        /// ```
1254        #[stable(feature = "euclidean_division", since = "1.38.0")]
1255        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1256        #[must_use = "this returns the result of the operation, \
1257                      without modifying the original"]
1258        #[inline]
1259        pub const fn checked_rem_euclid(self, rhs: Self) -> Option<Self> {
1260            if intrinsics::unlikely(rhs == 0) {
1261                None
1262            } else {
1263                Some(self.rem_euclid(rhs))
1264            }
1265        }
1266
1267        /// Strict Euclidean modulo. Computes `self.rem_euclid(rhs)`.
1268        ///
1269        /// Strict modulo calculation on unsigned types is just the regular
1270        /// remainder calculation. There's no way overflow could ever happen.
1271        /// This function exists so that all operations are accounted for in the
1272        /// strict operations. Since, for the positive integers, all common
1273        /// definitions of division are equal, this is exactly equal to
1274        /// `self.strict_rem(rhs)`.
1275        ///
1276        /// # Panics
1277        ///
1278        /// This function will panic if `rhs` is zero.
1279        ///
1280        /// # Examples
1281        ///
1282        /// ```
1283        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_rem_euclid(10), 0);")]
1284        /// ```
1285        ///
1286        /// The following panics because of division by zero:
1287        ///
1288        /// ```should_panic
1289        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem_euclid(0);")]
1290        /// ```
1291        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1292        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1293        #[must_use = "this returns the result of the operation, \
1294                      without modifying the original"]
1295        #[inline(always)]
1296        #[track_caller]
1297        pub const fn strict_rem_euclid(self, rhs: Self) -> Self {
1298            self % rhs
1299        }
1300
1301        /// Same value as `self | other`, but UB if any bit position is set in both inputs.
1302        ///
1303        /// This is a situational micro-optimization for places where you'd rather
1304        /// use addition on some platforms and bitwise or on other platforms, based
1305        /// on exactly which instructions combine better with whatever else you're
1306        /// doing.  Note that there's no reason to bother using this for places
1307        /// where it's clear from the operations involved that they can't overlap.
1308        /// For example, if you're combining `u16`s into a `u32` with
1309        /// `((a as u32) << 16) | (b as u32)`, that's fine, as the backend will
1310        /// know those sides of the `|` are disjoint without needing help.
1311        ///
1312        /// # Examples
1313        ///
1314        /// ```
1315        /// #![feature(disjoint_bitor)]
1316        ///
1317        /// // SAFETY: `1` and `4` have no bits in common.
1318        /// unsafe {
1319        #[doc = concat!("    assert_eq!(1_", stringify!($SelfT), ".unchecked_disjoint_bitor(4), 5);")]
1320        /// }
1321        /// ```
1322        ///
1323        /// # Safety
1324        ///
1325        /// Requires that `(self & other) == 0`, otherwise it's immediate UB.
1326        ///
1327        /// Equivalently, requires that `(self | other) == (self + other)`.
1328        #[unstable(feature = "disjoint_bitor", issue = "135758")]
1329        #[rustc_const_unstable(feature = "disjoint_bitor", issue = "135758")]
1330        #[inline]
1331        pub const unsafe fn unchecked_disjoint_bitor(self, other: Self) -> Self {
1332            assert_unsafe_precondition!(
1333                check_language_ub,
1334                concat!(stringify!($SelfT), "::unchecked_disjoint_bitor cannot have overlapping bits"),
1335                (
1336                    lhs: $SelfT = self,
1337                    rhs: $SelfT = other,
1338                ) => (lhs & rhs) == 0,
1339            );
1340
1341            // SAFETY: Same precondition
1342            unsafe { intrinsics::disjoint_bitor(self, other) }
1343        }
1344
1345        /// Returns the logarithm of the number with respect to an arbitrary base,
1346        /// rounded down.
1347        ///
1348        /// This method might not be optimized owing to implementation details;
1349        /// `ilog2` can produce results more efficiently for base 2, and `ilog10`
1350        /// can produce results more efficiently for base 10.
1351        ///
1352        /// # Panics
1353        ///
1354        /// This function will panic if `self` is zero, or if `base` is less than 2.
1355        ///
1356        /// # Examples
1357        ///
1358        /// ```
1359        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")]
1360        /// ```
1361        #[stable(feature = "int_log", since = "1.67.0")]
1362        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1363        #[must_use = "this returns the result of the operation, \
1364                      without modifying the original"]
1365        #[inline]
1366        #[track_caller]
1367        pub const fn ilog(self, base: Self) -> u32 {
1368            assert!(base >= 2, "base of integer logarithm must be at least 2");
1369            if let Some(log) = self.checked_ilog(base) {
1370                log
1371            } else {
1372                int_log10::panic_for_nonpositive_argument()
1373            }
1374        }
1375
1376        /// Returns the base 2 logarithm of the number, rounded down.
1377        ///
1378        /// # Panics
1379        ///
1380        /// This function will panic if `self` is zero.
1381        ///
1382        /// # Examples
1383        ///
1384        /// ```
1385        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")]
1386        /// ```
1387        #[stable(feature = "int_log", since = "1.67.0")]
1388        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1389        #[must_use = "this returns the result of the operation, \
1390                      without modifying the original"]
1391        #[inline]
1392        #[track_caller]
1393        pub const fn ilog2(self) -> u32 {
1394            if let Some(log) = self.checked_ilog2() {
1395                log
1396            } else {
1397                int_log10::panic_for_nonpositive_argument()
1398            }
1399        }
1400
1401        /// Returns the base 10 logarithm of the number, rounded down.
1402        ///
1403        /// # Panics
1404        ///
1405        /// This function will panic if `self` is zero.
1406        ///
1407        /// # Example
1408        ///
1409        /// ```
1410        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")]
1411        /// ```
1412        #[stable(feature = "int_log", since = "1.67.0")]
1413        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1414        #[must_use = "this returns the result of the operation, \
1415                      without modifying the original"]
1416        #[inline]
1417        #[track_caller]
1418        pub const fn ilog10(self) -> u32 {
1419            if let Some(log) = self.checked_ilog10() {
1420                log
1421            } else {
1422                int_log10::panic_for_nonpositive_argument()
1423            }
1424        }
1425
1426        /// Returns the logarithm of the number with respect to an arbitrary base,
1427        /// rounded down.
1428        ///
1429        /// Returns `None` if the number is zero, or if the base is not at least 2.
1430        ///
1431        /// This method might not be optimized owing to implementation details;
1432        /// `checked_ilog2` can produce results more efficiently for base 2, and
1433        /// `checked_ilog10` can produce results more efficiently for base 10.
1434        ///
1435        /// # Examples
1436        ///
1437        /// ```
1438        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")]
1439        /// ```
1440        #[stable(feature = "int_log", since = "1.67.0")]
1441        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1442        #[must_use = "this returns the result of the operation, \
1443                      without modifying the original"]
1444        #[inline]
1445        pub const fn checked_ilog(self, base: Self) -> Option<u32> {
1446            if self <= 0 || base <= 1 {
1447                None
1448            } else if self < base {
1449                Some(0)
1450            } else {
1451                // Since base >= self, n >= 1
1452                let mut n = 1;
1453                let mut r = base;
1454
1455                // Optimization for 128 bit wide integers.
1456                if Self::BITS == 128 {
1457                    // The following is a correct lower bound for ⌊log(base,self)⌋ because
1458                    //
1459                    // log(base,self) = log(2,self) / log(2,base)
1460                    //                ≥ ⌊log(2,self)⌋ / (⌊log(2,base)⌋ + 1)
1461                    //
1462                    // hence
1463                    //
1464                    // ⌊log(base,self)⌋ ≥ ⌊ ⌊log(2,self)⌋ / (⌊log(2,base)⌋ + 1) ⌋ .
1465                    n = self.ilog2() / (base.ilog2() + 1);
1466                    r = base.pow(n);
1467                }
1468
1469                while r <= self / base {
1470                    n += 1;
1471                    r *= base;
1472                }
1473                Some(n)
1474            }
1475        }
1476
1477        /// Returns the base 2 logarithm of the number, rounded down.
1478        ///
1479        /// Returns `None` if the number is zero.
1480        ///
1481        /// # Examples
1482        ///
1483        /// ```
1484        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")]
1485        /// ```
1486        #[stable(feature = "int_log", since = "1.67.0")]
1487        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1488        #[must_use = "this returns the result of the operation, \
1489                      without modifying the original"]
1490        #[inline]
1491        pub const fn checked_ilog2(self) -> Option<u32> {
1492            match NonZero::new(self) {
1493                Some(x) => Some(x.ilog2()),
1494                None => None,
1495            }
1496        }
1497
1498        /// Returns the base 10 logarithm of the number, rounded down.
1499        ///
1500        /// Returns `None` if the number is zero.
1501        ///
1502        /// # Examples
1503        ///
1504        /// ```
1505        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")]
1506        /// ```
1507        #[stable(feature = "int_log", since = "1.67.0")]
1508        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1509        #[must_use = "this returns the result of the operation, \
1510                      without modifying the original"]
1511        #[inline]
1512        pub const fn checked_ilog10(self) -> Option<u32> {
1513            match NonZero::new(self) {
1514                Some(x) => Some(x.ilog10()),
1515                None => None,
1516            }
1517        }
1518
1519        /// Checked negation. Computes `-self`, returning `None` unless `self ==
1520        /// 0`.
1521        ///
1522        /// Note that negating any positive integer will overflow.
1523        ///
1524        /// # Examples
1525        ///
1526        /// ```
1527        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".checked_neg(), Some(0));")]
1528        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_neg(), None);")]
1529        /// ```
1530        #[stable(feature = "wrapping", since = "1.7.0")]
1531        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1532        #[must_use = "this returns the result of the operation, \
1533                      without modifying the original"]
1534        #[inline]
1535        pub const fn checked_neg(self) -> Option<Self> {
1536            let (a, b) = self.overflowing_neg();
1537            if intrinsics::unlikely(b) { None } else { Some(a) }
1538        }
1539
1540        /// Strict negation. Computes `-self`, panicking unless `self ==
1541        /// 0`.
1542        ///
1543        /// Note that negating any positive integer will overflow.
1544        ///
1545        /// # Panics
1546        ///
1547        /// ## Overflow behavior
1548        ///
1549        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1550        ///
1551        /// # Examples
1552        ///
1553        /// ```
1554        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".strict_neg(), 0);")]
1555        /// ```
1556        ///
1557        /// The following panics because of overflow:
1558        ///
1559        /// ```should_panic
1560        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_neg();")]
1561        ///
1562        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1563        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1564        #[must_use = "this returns the result of the operation, \
1565                      without modifying the original"]
1566        #[inline]
1567        #[track_caller]
1568        pub const fn strict_neg(self) -> Self {
1569            let (a, b) = self.overflowing_neg();
1570            if b { overflow_panic::neg() } else { a }
1571        }
1572
1573        /// Checked shift left. Computes `self << rhs`, returning `None`
1574        /// if `rhs` is larger than or equal to the number of bits in `self`.
1575        ///
1576        /// # Examples
1577        ///
1578        /// ```
1579        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(4), Some(0x10));")]
1580        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(129), None);")]
1581        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(", stringify!($BITS_MINUS_ONE), "), Some(0));")]
1582        /// ```
1583        #[stable(feature = "wrapping", since = "1.7.0")]
1584        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1585        #[must_use = "this returns the result of the operation, \
1586                      without modifying the original"]
1587        #[inline]
1588        pub const fn checked_shl(self, rhs: u32) -> Option<Self> {
1589            // Not using overflowing_shl as that's a wrapping shift
1590            if rhs < Self::BITS {
1591                // SAFETY: just checked the RHS is in-range
1592                Some(unsafe { self.unchecked_shl(rhs) })
1593            } else {
1594                None
1595            }
1596        }
1597
1598        /// Strict shift left. Computes `self << rhs`, panicking if `rhs` is larger
1599        /// than or equal to the number of bits in `self`.
1600        ///
1601        /// # Panics
1602        ///
1603        /// ## Overflow behavior
1604        ///
1605        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1606        ///
1607        /// # Examples
1608        ///
1609        /// ```
1610        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".strict_shl(4), 0x10);")]
1611        /// ```
1612        ///
1613        /// The following panics because of overflow:
1614        ///
1615        /// ```should_panic
1616        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shl(129);")]
1617        /// ```
1618        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1619        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1620        #[must_use = "this returns the result of the operation, \
1621                      without modifying the original"]
1622        #[inline]
1623        #[track_caller]
1624        pub const fn strict_shl(self, rhs: u32) -> Self {
1625            let (a, b) = self.overflowing_shl(rhs);
1626            if b { overflow_panic::shl() } else { a }
1627        }
1628
1629        /// Unchecked shift left. Computes `self << rhs`, assuming that
1630        /// `rhs` is less than the number of bits in `self`.
1631        ///
1632        /// # Safety
1633        ///
1634        /// This results in undefined behavior if `rhs` is larger than
1635        /// or equal to the number of bits in `self`,
1636        /// i.e. when [`checked_shl`] would return `None`.
1637        ///
1638        #[doc = concat!("[`checked_shl`]: ", stringify!($SelfT), "::checked_shl")]
1639        #[unstable(
1640            feature = "unchecked_shifts",
1641            reason = "niche optimization path",
1642            issue = "85122",
1643        )]
1644        #[must_use = "this returns the result of the operation, \
1645                      without modifying the original"]
1646        #[inline(always)]
1647        #[track_caller]
1648        pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
1649            assert_unsafe_precondition!(
1650                check_language_ub,
1651                concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"),
1652                (
1653                    rhs: u32 = rhs,
1654                ) => rhs < <$ActualT>::BITS,
1655            );
1656
1657            // SAFETY: this is guaranteed to be safe by the caller.
1658            unsafe {
1659                intrinsics::unchecked_shl(self, rhs)
1660            }
1661        }
1662
1663        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`.
1664        ///
1665        /// If `rhs` is larger or equal to the number of bits in `self`,
1666        /// the entire value is shifted out, and `0` is returned.
1667        ///
1668        /// # Examples
1669        ///
1670        /// ```
1671        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(4), 0x10);")]
1672        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(129), 0);")]
1673        /// ```
1674        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1675        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1676        #[must_use = "this returns the result of the operation, \
1677                      without modifying the original"]
1678        #[inline]
1679        pub const fn unbounded_shl(self, rhs: u32) -> $SelfT{
1680            if rhs < Self::BITS {
1681                // SAFETY:
1682                // rhs is just checked to be in-range above
1683                unsafe { self.unchecked_shl(rhs) }
1684            } else {
1685                0
1686            }
1687        }
1688
1689        /// Checked shift right. Computes `self >> rhs`, returning `None`
1690        /// if `rhs` is larger than or equal to the number of bits in `self`.
1691        ///
1692        /// # Examples
1693        ///
1694        /// ```
1695        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(4), Some(0x1));")]
1696        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(129), None);")]
1697        /// ```
1698        #[stable(feature = "wrapping", since = "1.7.0")]
1699        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1700        #[must_use = "this returns the result of the operation, \
1701                      without modifying the original"]
1702        #[inline]
1703        pub const fn checked_shr(self, rhs: u32) -> Option<Self> {
1704            // Not using overflowing_shr as that's a wrapping shift
1705            if rhs < Self::BITS {
1706                // SAFETY: just checked the RHS is in-range
1707                Some(unsafe { self.unchecked_shr(rhs) })
1708            } else {
1709                None
1710            }
1711        }
1712
1713        /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is
1714        /// larger than or equal to the number of bits in `self`.
1715        ///
1716        /// # Panics
1717        ///
1718        /// ## Overflow behavior
1719        ///
1720        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1721        ///
1722        /// # Examples
1723        ///
1724        /// ```
1725        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".strict_shr(4), 0x1);")]
1726        /// ```
1727        ///
1728        /// The following panics because of overflow:
1729        ///
1730        /// ```should_panic
1731        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shr(129);")]
1732        /// ```
1733        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1734        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1735        #[must_use = "this returns the result of the operation, \
1736                      without modifying the original"]
1737        #[inline]
1738        #[track_caller]
1739        pub const fn strict_shr(self, rhs: u32) -> Self {
1740            let (a, b) = self.overflowing_shr(rhs);
1741            if b { overflow_panic::shr() } else { a }
1742        }
1743
1744        /// Unchecked shift right. Computes `self >> rhs`, assuming that
1745        /// `rhs` is less than the number of bits in `self`.
1746        ///
1747        /// # Safety
1748        ///
1749        /// This results in undefined behavior if `rhs` is larger than
1750        /// or equal to the number of bits in `self`,
1751        /// i.e. when [`checked_shr`] would return `None`.
1752        ///
1753        #[doc = concat!("[`checked_shr`]: ", stringify!($SelfT), "::checked_shr")]
1754        #[unstable(
1755            feature = "unchecked_shifts",
1756            reason = "niche optimization path",
1757            issue = "85122",
1758        )]
1759        #[must_use = "this returns the result of the operation, \
1760                      without modifying the original"]
1761        #[inline(always)]
1762        #[track_caller]
1763        pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
1764            assert_unsafe_precondition!(
1765                check_language_ub,
1766                concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"),
1767                (
1768                    rhs: u32 = rhs,
1769                ) => rhs < <$ActualT>::BITS,
1770            );
1771
1772            // SAFETY: this is guaranteed to be safe by the caller.
1773            unsafe {
1774                intrinsics::unchecked_shr(self, rhs)
1775            }
1776        }
1777
1778        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`.
1779        ///
1780        /// If `rhs` is larger or equal to the number of bits in `self`,
1781        /// the entire value is shifted out, and `0` is returned.
1782        ///
1783        /// # Examples
1784        ///
1785        /// ```
1786        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(4), 0x1);")]
1787        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(129), 0);")]
1788        /// ```
1789        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1790        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1791        #[must_use = "this returns the result of the operation, \
1792                      without modifying the original"]
1793        #[inline]
1794        pub const fn unbounded_shr(self, rhs: u32) -> $SelfT{
1795            if rhs < Self::BITS {
1796                // SAFETY:
1797                // rhs is just checked to be in-range above
1798                unsafe { self.unchecked_shr(rhs) }
1799            } else {
1800                0
1801            }
1802        }
1803
1804        /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if
1805        /// overflow occurred.
1806        ///
1807        /// # Examples
1808        ///
1809        /// ```
1810        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_pow(5), Some(32));")]
1811        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_pow(2), None);")]
1812        /// ```
1813        #[stable(feature = "no_panic_pow", since = "1.34.0")]
1814        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
1815        #[must_use = "this returns the result of the operation, \
1816                      without modifying the original"]
1817        #[inline]
1818        pub const fn checked_pow(self, mut exp: u32) -> Option<Self> {
1819            if exp == 0 {
1820                return Some(1);
1821            }
1822            let mut base = self;
1823            let mut acc: Self = 1;
1824
1825            loop {
1826                if (exp & 1) == 1 {
1827                    acc = try_opt!(acc.checked_mul(base));
1828                    // since exp!=0, finally the exp must be 1.
1829                    if exp == 1 {
1830                        return Some(acc);
1831                    }
1832                }
1833                exp /= 2;
1834                base = try_opt!(base.checked_mul(base));
1835            }
1836        }
1837
1838        /// Strict exponentiation. Computes `self.pow(exp)`, panicking if
1839        /// overflow occurred.
1840        ///
1841        /// # Panics
1842        ///
1843        /// ## Overflow behavior
1844        ///
1845        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1846        ///
1847        /// # Examples
1848        ///
1849        /// ```
1850        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".strict_pow(5), 32);")]
1851        /// ```
1852        ///
1853        /// The following panics because of overflow:
1854        ///
1855        /// ```should_panic
1856        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_pow(2);")]
1857        /// ```
1858        #[stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1859        #[rustc_const_stable(feature = "strict_overflow_ops", since = "CURRENT_RUSTC_VERSION")]
1860        #[must_use = "this returns the result of the operation, \
1861                      without modifying the original"]
1862        #[inline]
1863        #[track_caller]
1864        pub const fn strict_pow(self, mut exp: u32) -> Self {
1865            if exp == 0 {
1866                return 1;
1867            }
1868            let mut base = self;
1869            let mut acc: Self = 1;
1870
1871            loop {
1872                if (exp & 1) == 1 {
1873                    acc = acc.strict_mul(base);
1874                    // since exp!=0, finally the exp must be 1.
1875                    if exp == 1 {
1876                        return acc;
1877                    }
1878                }
1879                exp /= 2;
1880                base = base.strict_mul(base);
1881            }
1882        }
1883
1884        /// Saturating integer addition. Computes `self + rhs`, saturating at
1885        /// the numeric bounds instead of overflowing.
1886        ///
1887        /// # Examples
1888        ///
1889        /// ```
1890        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_add(1), 101);")]
1891        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add(127), ", stringify!($SelfT), "::MAX);")]
1892        /// ```
1893        #[stable(feature = "rust1", since = "1.0.0")]
1894        #[must_use = "this returns the result of the operation, \
1895                      without modifying the original"]
1896        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1897        #[inline(always)]
1898        pub const fn saturating_add(self, rhs: Self) -> Self {
1899            intrinsics::saturating_add(self, rhs)
1900        }
1901
1902        /// Saturating addition with a signed integer. Computes `self + rhs`,
1903        /// saturating at the numeric bounds instead of overflowing.
1904        ///
1905        /// # Examples
1906        ///
1907        /// ```
1908        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(2), 3);")]
1909        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(-2), 0);")]
1910        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_add_signed(4), ", stringify!($SelfT), "::MAX);")]
1911        /// ```
1912        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1913        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1914        #[must_use = "this returns the result of the operation, \
1915                      without modifying the original"]
1916        #[inline]
1917        pub const fn saturating_add_signed(self, rhs: $SignedT) -> Self {
1918            let (res, overflow) = self.overflowing_add(rhs as Self);
1919            if overflow == (rhs < 0) {
1920                res
1921            } else if overflow {
1922                Self::MAX
1923            } else {
1924                0
1925            }
1926        }
1927
1928        /// Saturating integer subtraction. Computes `self - rhs`, saturating
1929        /// at the numeric bounds instead of overflowing.
1930        ///
1931        /// # Examples
1932        ///
1933        /// ```
1934        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub(27), 73);")]
1935        #[doc = concat!("assert_eq!(13", stringify!($SelfT), ".saturating_sub(127), 0);")]
1936        /// ```
1937        #[stable(feature = "rust1", since = "1.0.0")]
1938        #[must_use = "this returns the result of the operation, \
1939                      without modifying the original"]
1940        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1941        #[inline(always)]
1942        pub const fn saturating_sub(self, rhs: Self) -> Self {
1943            intrinsics::saturating_sub(self, rhs)
1944        }
1945
1946        /// Saturating integer subtraction. Computes `self` - `rhs`, saturating at
1947        /// the numeric bounds instead of overflowing.
1948        ///
1949        /// # Examples
1950        ///
1951        /// ```
1952        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_sub_signed(2), 0);")]
1953        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_sub_signed(-2), 3);")]
1954        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_sub_signed(-4), ", stringify!($SelfT), "::MAX);")]
1955        /// ```
1956        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
1957        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
1958        #[must_use = "this returns the result of the operation, \
1959                      without modifying the original"]
1960        #[inline]
1961        pub const fn saturating_sub_signed(self, rhs: $SignedT) -> Self {
1962            let (res, overflow) = self.overflowing_sub_signed(rhs);
1963
1964            if !overflow {
1965                res
1966            } else if rhs < 0 {
1967                Self::MAX
1968            } else {
1969                0
1970            }
1971        }
1972
1973        /// Saturating integer multiplication. Computes `self * rhs`,
1974        /// saturating at the numeric bounds instead of overflowing.
1975        ///
1976        /// # Examples
1977        ///
1978        /// ```
1979        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".saturating_mul(10), 20);")]
1980        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).saturating_mul(10), ", stringify!($SelfT),"::MAX);")]
1981        /// ```
1982        #[stable(feature = "wrapping", since = "1.7.0")]
1983        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1984        #[must_use = "this returns the result of the operation, \
1985                      without modifying the original"]
1986        #[inline]
1987        pub const fn saturating_mul(self, rhs: Self) -> Self {
1988            match self.checked_mul(rhs) {
1989                Some(x) => x,
1990                None => Self::MAX,
1991            }
1992        }
1993
1994        /// Saturating integer division. Computes `self / rhs`, saturating at the
1995        /// numeric bounds instead of overflowing.
1996        ///
1997        /// # Panics
1998        ///
1999        /// This function will panic if `rhs` is zero.
2000        ///
2001        /// # Examples
2002        ///
2003        /// ```
2004        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".saturating_div(2), 2);")]
2005        ///
2006        /// ```
2007        #[stable(feature = "saturating_div", since = "1.58.0")]
2008        #[rustc_const_stable(feature = "saturating_div", since = "1.58.0")]
2009        #[must_use = "this returns the result of the operation, \
2010                      without modifying the original"]
2011        #[inline]
2012        #[track_caller]
2013        pub const fn saturating_div(self, rhs: Self) -> Self {
2014            // on unsigned types, there is no overflow in integer division
2015            self.wrapping_div(rhs)
2016        }
2017
2018        /// Saturating integer exponentiation. Computes `self.pow(exp)`,
2019        /// saturating at the numeric bounds instead of overflowing.
2020        ///
2021        /// # Examples
2022        ///
2023        /// ```
2024        #[doc = concat!("assert_eq!(4", stringify!($SelfT), ".saturating_pow(3), 64);")]
2025        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_pow(2), ", stringify!($SelfT), "::MAX);")]
2026        /// ```
2027        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2028        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2029        #[must_use = "this returns the result of the operation, \
2030                      without modifying the original"]
2031        #[inline]
2032        pub const fn saturating_pow(self, exp: u32) -> Self {
2033            match self.checked_pow(exp) {
2034                Some(x) => x,
2035                None => Self::MAX,
2036            }
2037        }
2038
2039        /// Wrapping (modular) addition. Computes `self + rhs`,
2040        /// wrapping around at the boundary of the type.
2041        ///
2042        /// # Examples
2043        ///
2044        /// ```
2045        #[doc = concat!("assert_eq!(200", stringify!($SelfT), ".wrapping_add(55), 255);")]
2046        #[doc = concat!("assert_eq!(200", stringify!($SelfT), ".wrapping_add(", stringify!($SelfT), "::MAX), 199);")]
2047        /// ```
2048        #[stable(feature = "rust1", since = "1.0.0")]
2049        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2050        #[must_use = "this returns the result of the operation, \
2051                      without modifying the original"]
2052        #[inline(always)]
2053        pub const fn wrapping_add(self, rhs: Self) -> Self {
2054            intrinsics::wrapping_add(self, rhs)
2055        }
2056
2057        /// Wrapping (modular) addition with a signed integer. Computes
2058        /// `self + rhs`, wrapping around at the boundary of the type.
2059        ///
2060        /// # Examples
2061        ///
2062        /// ```
2063        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(2), 3);")]
2064        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(-2), ", stringify!($SelfT), "::MAX);")]
2065        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_add_signed(4), 1);")]
2066        /// ```
2067        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2068        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2069        #[must_use = "this returns the result of the operation, \
2070                      without modifying the original"]
2071        #[inline]
2072        pub const fn wrapping_add_signed(self, rhs: $SignedT) -> Self {
2073            self.wrapping_add(rhs as Self)
2074        }
2075
2076        /// Wrapping (modular) subtraction. Computes `self - rhs`,
2077        /// wrapping around at the boundary of the type.
2078        ///
2079        /// # Examples
2080        ///
2081        /// ```
2082        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_sub(100), 0);")]
2083        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_sub(", stringify!($SelfT), "::MAX), 101);")]
2084        /// ```
2085        #[stable(feature = "rust1", since = "1.0.0")]
2086        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2087        #[must_use = "this returns the result of the operation, \
2088                      without modifying the original"]
2089        #[inline(always)]
2090        pub const fn wrapping_sub(self, rhs: Self) -> Self {
2091            intrinsics::wrapping_sub(self, rhs)
2092        }
2093
2094        /// Wrapping (modular) subtraction with a signed integer. Computes
2095        /// `self - rhs`, wrapping around at the boundary of the type.
2096        ///
2097        /// # Examples
2098        ///
2099        /// ```
2100        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_sub_signed(2), ", stringify!($SelfT), "::MAX);")]
2101        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_sub_signed(-2), 3);")]
2102        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_sub_signed(-4), 1);")]
2103        /// ```
2104        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
2105        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
2106        #[must_use = "this returns the result of the operation, \
2107                      without modifying the original"]
2108        #[inline]
2109        pub const fn wrapping_sub_signed(self, rhs: $SignedT) -> Self {
2110            self.wrapping_sub(rhs as Self)
2111        }
2112
2113        /// Wrapping (modular) multiplication. Computes `self *
2114        /// rhs`, wrapping around at the boundary of the type.
2115        ///
2116        /// # Examples
2117        ///
2118        /// Please note that this example is shared among integer types, which is why `u8` is used.
2119        ///
2120        /// ```
2121        /// assert_eq!(10u8.wrapping_mul(12), 120);
2122        /// assert_eq!(25u8.wrapping_mul(12), 44);
2123        /// ```
2124        #[stable(feature = "rust1", since = "1.0.0")]
2125        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2126        #[must_use = "this returns the result of the operation, \
2127                      without modifying the original"]
2128        #[inline(always)]
2129        pub const fn wrapping_mul(self, rhs: Self) -> Self {
2130            intrinsics::wrapping_mul(self, rhs)
2131        }
2132
2133        /// Wrapping (modular) division. Computes `self / rhs`.
2134        ///
2135        /// Wrapped division on unsigned types is just normal division. There's
2136        /// no way wrapping could ever happen. This function exists so that all
2137        /// operations are accounted for in the wrapping operations.
2138        ///
2139        /// # Panics
2140        ///
2141        /// This function will panic if `rhs` is zero.
2142        ///
2143        /// # Examples
2144        ///
2145        /// ```
2146        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div(10), 10);")]
2147        /// ```
2148        #[stable(feature = "num_wrapping", since = "1.2.0")]
2149        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2150        #[must_use = "this returns the result of the operation, \
2151                      without modifying the original"]
2152        #[inline(always)]
2153        #[track_caller]
2154        pub const fn wrapping_div(self, rhs: Self) -> Self {
2155            self / rhs
2156        }
2157
2158        /// Wrapping Euclidean division. Computes `self.div_euclid(rhs)`.
2159        ///
2160        /// Wrapped division on unsigned types is just normal division. There's
2161        /// no way wrapping could ever happen. This function exists so that all
2162        /// operations are accounted for in the wrapping operations. Since, for
2163        /// the positive integers, all common definitions of division are equal,
2164        /// this is exactly equal to `self.wrapping_div(rhs)`.
2165        ///
2166        /// # Panics
2167        ///
2168        /// This function will panic if `rhs` is zero.
2169        ///
2170        /// # Examples
2171        ///
2172        /// ```
2173        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div_euclid(10), 10);")]
2174        /// ```
2175        #[stable(feature = "euclidean_division", since = "1.38.0")]
2176        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2177        #[must_use = "this returns the result of the operation, \
2178                      without modifying the original"]
2179        #[inline(always)]
2180        #[track_caller]
2181        pub const fn wrapping_div_euclid(self, rhs: Self) -> Self {
2182            self / rhs
2183        }
2184
2185        /// Wrapping (modular) remainder. Computes `self % rhs`.
2186        ///
2187        /// Wrapped remainder calculation on unsigned types is just the regular
2188        /// remainder calculation. There's no way wrapping could ever happen.
2189        /// This function exists so that all operations are accounted for in the
2190        /// wrapping operations.
2191        ///
2192        /// # Panics
2193        ///
2194        /// This function will panic if `rhs` is zero.
2195        ///
2196        /// # Examples
2197        ///
2198        /// ```
2199        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem(10), 0);")]
2200        /// ```
2201        #[stable(feature = "num_wrapping", since = "1.2.0")]
2202        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2203        #[must_use = "this returns the result of the operation, \
2204                      without modifying the original"]
2205        #[inline(always)]
2206        #[track_caller]
2207        pub const fn wrapping_rem(self, rhs: Self) -> Self {
2208            self % rhs
2209        }
2210
2211        /// Wrapping Euclidean modulo. Computes `self.rem_euclid(rhs)`.
2212        ///
2213        /// Wrapped modulo calculation on unsigned types is just the regular
2214        /// remainder calculation. There's no way wrapping could ever happen.
2215        /// This function exists so that all operations are accounted for in the
2216        /// wrapping operations. Since, for the positive integers, all common
2217        /// definitions of division are equal, this is exactly equal to
2218        /// `self.wrapping_rem(rhs)`.
2219        ///
2220        /// # Panics
2221        ///
2222        /// This function will panic if `rhs` is zero.
2223        ///
2224        /// # Examples
2225        ///
2226        /// ```
2227        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem_euclid(10), 0);")]
2228        /// ```
2229        #[stable(feature = "euclidean_division", since = "1.38.0")]
2230        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2231        #[must_use = "this returns the result of the operation, \
2232                      without modifying the original"]
2233        #[inline(always)]
2234        #[track_caller]
2235        pub const fn wrapping_rem_euclid(self, rhs: Self) -> Self {
2236            self % rhs
2237        }
2238
2239        /// Wrapping (modular) negation. Computes `-self`,
2240        /// wrapping around at the boundary of the type.
2241        ///
2242        /// Since unsigned types do not have negative equivalents
2243        /// all applications of this function will wrap (except for `-0`).
2244        /// For values smaller than the corresponding signed type's maximum
2245        /// the result is the same as casting the corresponding signed value.
2246        /// Any larger values are equivalent to `MAX + 1 - (val - MAX - 1)` where
2247        /// `MAX` is the corresponding signed type's maximum.
2248        ///
2249        /// # Examples
2250        ///
2251        /// ```
2252        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".wrapping_neg(), 0);")]
2253        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_neg(), 1);")]
2254        #[doc = concat!("assert_eq!(13_", stringify!($SelfT), ".wrapping_neg(), (!13) + 1);")]
2255        #[doc = concat!("assert_eq!(42_", stringify!($SelfT), ".wrapping_neg(), !(42 - 1));")]
2256        /// ```
2257        #[stable(feature = "num_wrapping", since = "1.2.0")]
2258        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2259        #[must_use = "this returns the result of the operation, \
2260                      without modifying the original"]
2261        #[inline(always)]
2262        pub const fn wrapping_neg(self) -> Self {
2263            (0 as $SelfT).wrapping_sub(self)
2264        }
2265
2266        /// Panic-free bitwise shift-left; yields `self << mask(rhs)`,
2267        /// where `mask` removes any high-order bits of `rhs` that
2268        /// would cause the shift to exceed the bitwidth of the type.
2269        ///
2270        /// Note that this is *not* the same as a rotate-left; the
2271        /// RHS of a wrapping shift-left is restricted to the range
2272        /// of the type, rather than the bits shifted out of the LHS
2273        /// being returned to the other end. The primitive integer
2274        /// types all implement a [`rotate_left`](Self::rotate_left) function,
2275        /// which may be what you want instead.
2276        ///
2277        /// # Examples
2278        ///
2279        /// ```
2280        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_shl(7), 128);")]
2281        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_shl(128), 1);")]
2282        /// ```
2283        #[stable(feature = "num_wrapping", since = "1.2.0")]
2284        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2285        #[must_use = "this returns the result of the operation, \
2286                      without modifying the original"]
2287        #[inline(always)]
2288        pub const fn wrapping_shl(self, rhs: u32) -> Self {
2289            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2290            // out of bounds
2291            unsafe {
2292                self.unchecked_shl(rhs & (Self::BITS - 1))
2293            }
2294        }
2295
2296        /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`,
2297        /// where `mask` removes any high-order bits of `rhs` that
2298        /// would cause the shift to exceed the bitwidth of the type.
2299        ///
2300        /// Note that this is *not* the same as a rotate-right; the
2301        /// RHS of a wrapping shift-right is restricted to the range
2302        /// of the type, rather than the bits shifted out of the LHS
2303        /// being returned to the other end. The primitive integer
2304        /// types all implement a [`rotate_right`](Self::rotate_right) function,
2305        /// which may be what you want instead.
2306        ///
2307        /// # Examples
2308        ///
2309        /// ```
2310        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".wrapping_shr(7), 1);")]
2311        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".wrapping_shr(128), 128);")]
2312        /// ```
2313        #[stable(feature = "num_wrapping", since = "1.2.0")]
2314        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2315        #[must_use = "this returns the result of the operation, \
2316                      without modifying the original"]
2317        #[inline(always)]
2318        pub const fn wrapping_shr(self, rhs: u32) -> Self {
2319            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2320            // out of bounds
2321            unsafe {
2322                self.unchecked_shr(rhs & (Self::BITS - 1))
2323            }
2324        }
2325
2326        /// Wrapping (modular) exponentiation. Computes `self.pow(exp)`,
2327        /// wrapping around at the boundary of the type.
2328        ///
2329        /// # Examples
2330        ///
2331        /// ```
2332        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_pow(5), 243);")]
2333        /// assert_eq!(3u8.wrapping_pow(6), 217);
2334        /// ```
2335        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2336        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2337        #[must_use = "this returns the result of the operation, \
2338                      without modifying the original"]
2339        #[inline]
2340        pub const fn wrapping_pow(self, mut exp: u32) -> Self {
2341            if exp == 0 {
2342                return 1;
2343            }
2344            let mut base = self;
2345            let mut acc: Self = 1;
2346
2347            if intrinsics::is_val_statically_known(exp) {
2348                while exp > 1 {
2349                    if (exp & 1) == 1 {
2350                        acc = acc.wrapping_mul(base);
2351                    }
2352                    exp /= 2;
2353                    base = base.wrapping_mul(base);
2354                }
2355
2356                // since exp!=0, finally the exp must be 1.
2357                // Deal with the final bit of the exponent separately, since
2358                // squaring the base afterwards is not necessary.
2359                acc.wrapping_mul(base)
2360            } else {
2361                // This is faster than the above when the exponent is not known
2362                // at compile time. We can't use the same code for the constant
2363                // exponent case because LLVM is currently unable to unroll
2364                // this loop.
2365                loop {
2366                    if (exp & 1) == 1 {
2367                        acc = acc.wrapping_mul(base);
2368                        // since exp!=0, finally the exp must be 1.
2369                        if exp == 1 {
2370                            return acc;
2371                        }
2372                    }
2373                    exp /= 2;
2374                    base = base.wrapping_mul(base);
2375                }
2376            }
2377        }
2378
2379        /// Calculates `self` + `rhs`.
2380        ///
2381        /// Returns a tuple of the addition along with a boolean indicating
2382        /// whether an arithmetic overflow would occur. If an overflow would
2383        /// have occurred then the wrapped value is returned.
2384        ///
2385        /// # Examples
2386        ///
2387        /// ```
2388        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_add(2), (7, false));")]
2389        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.overflowing_add(1), (0, true));")]
2390        /// ```
2391        #[stable(feature = "wrapping", since = "1.7.0")]
2392        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2393        #[must_use = "this returns the result of the operation, \
2394                      without modifying the original"]
2395        #[inline(always)]
2396        pub const fn overflowing_add(self, rhs: Self) -> (Self, bool) {
2397            let (a, b) = intrinsics::add_with_overflow(self as $ActualT, rhs as $ActualT);
2398            (a as Self, b)
2399        }
2400
2401        /// Calculates `self` + `rhs` + `carry` and returns a tuple containing
2402        /// the sum and the output carry.
2403        ///
2404        /// Performs "ternary addition" of two integer operands and a carry-in
2405        /// bit, and returns an output integer and a carry-out bit. This allows
2406        /// chaining together multiple additions to create a wider addition, and
2407        /// can be useful for bignum addition.
2408        ///
2409        #[doc = concat!("This can be thought of as a ", stringify!($BITS), "-bit \"full adder\", in the electronics sense.")]
2410        ///
2411        /// If the input carry is false, this method is equivalent to
2412        /// [`overflowing_add`](Self::overflowing_add), and the output carry is
2413        /// equal to the overflow flag. Note that although carry and overflow
2414        /// flags are similar for unsigned integers, they are different for
2415        /// signed integers.
2416        ///
2417        /// # Examples
2418        ///
2419        /// ```
2420        /// #![feature(bigint_helper_methods)]
2421        ///
2422        #[doc = concat!("//    3  MAX    (a = 3 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2423        #[doc = concat!("// +  5    7    (b = 5 × 2^", stringify!($BITS), " + 7)")]
2424        /// // ---------
2425        #[doc = concat!("//    9    6    (sum = 9 × 2^", stringify!($BITS), " + 6)")]
2426        ///
2427        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (3, ", stringify!($SelfT), "::MAX);")]
2428        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (5, 7);")]
2429        /// let carry0 = false;
2430        ///
2431        /// let (sum0, carry1) = a0.carrying_add(b0, carry0);
2432        /// assert_eq!(carry1, true);
2433        /// let (sum1, carry2) = a1.carrying_add(b1, carry1);
2434        /// assert_eq!(carry2, false);
2435        ///
2436        /// assert_eq!((sum1, sum0), (9, 6));
2437        /// ```
2438        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2439        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2440        #[must_use = "this returns the result of the operation, \
2441                      without modifying the original"]
2442        #[inline]
2443        pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) {
2444            // note: longer-term this should be done via an intrinsic, but this has been shown
2445            //   to generate optimal code for now, and LLVM doesn't have an equivalent intrinsic
2446            let (a, c1) = self.overflowing_add(rhs);
2447            let (b, c2) = a.overflowing_add(carry as $SelfT);
2448            // Ideally LLVM would know this is disjoint without us telling them,
2449            // but it doesn't <https://github.com/llvm/llvm-project/issues/118162>
2450            // SAFETY: Only one of `c1` and `c2` can be set.
2451            // For c1 to be set we need to have overflowed, but if we did then
2452            // `a` is at most `MAX-1`, which means that `c2` cannot possibly
2453            // overflow because it's adding at most `1` (since it came from `bool`)
2454            (b, unsafe { intrinsics::disjoint_bitor(c1, c2) })
2455        }
2456
2457        /// Calculates `self` + `rhs` with a signed `rhs`.
2458        ///
2459        /// Returns a tuple of the addition along with a boolean indicating
2460        /// whether an arithmetic overflow would occur. If an overflow would
2461        /// have occurred then the wrapped value is returned.
2462        ///
2463        /// # Examples
2464        ///
2465        /// ```
2466        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(2), (3, false));")]
2467        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(-2), (", stringify!($SelfT), "::MAX, true));")]
2468        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_signed(4), (1, true));")]
2469        /// ```
2470        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2471        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2472        #[must_use = "this returns the result of the operation, \
2473                      without modifying the original"]
2474        #[inline]
2475        pub const fn overflowing_add_signed(self, rhs: $SignedT) -> (Self, bool) {
2476            let (res, overflowed) = self.overflowing_add(rhs as Self);
2477            (res, overflowed ^ (rhs < 0))
2478        }
2479
2480        /// Calculates `self` - `rhs`.
2481        ///
2482        /// Returns a tuple of the subtraction along with a boolean indicating
2483        /// whether an arithmetic overflow would occur. If an overflow would
2484        /// have occurred then the wrapped value is returned.
2485        ///
2486        /// # Examples
2487        ///
2488        /// ```
2489        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_sub(2), (3, false));")]
2490        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_sub(1), (", stringify!($SelfT), "::MAX, true));")]
2491        /// ```
2492        #[stable(feature = "wrapping", since = "1.7.0")]
2493        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2494        #[must_use = "this returns the result of the operation, \
2495                      without modifying the original"]
2496        #[inline(always)]
2497        pub const fn overflowing_sub(self, rhs: Self) -> (Self, bool) {
2498            let (a, b) = intrinsics::sub_with_overflow(self as $ActualT, rhs as $ActualT);
2499            (a as Self, b)
2500        }
2501
2502        /// Calculates `self` &minus; `rhs` &minus; `borrow` and returns a tuple
2503        /// containing the difference and the output borrow.
2504        ///
2505        /// Performs "ternary subtraction" by subtracting both an integer
2506        /// operand and a borrow-in bit from `self`, and returns an output
2507        /// integer and a borrow-out bit. This allows chaining together multiple
2508        /// subtractions to create a wider subtraction, and can be useful for
2509        /// bignum subtraction.
2510        ///
2511        /// # Examples
2512        ///
2513        /// ```
2514        /// #![feature(bigint_helper_methods)]
2515        ///
2516        #[doc = concat!("//    9    6    (a = 9 × 2^", stringify!($BITS), " + 6)")]
2517        #[doc = concat!("// -  5    7    (b = 5 × 2^", stringify!($BITS), " + 7)")]
2518        /// // ---------
2519        #[doc = concat!("//    3  MAX    (diff = 3 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2520        ///
2521        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (9, 6);")]
2522        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (5, 7);")]
2523        /// let borrow0 = false;
2524        ///
2525        /// let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0);
2526        /// assert_eq!(borrow1, true);
2527        /// let (diff1, borrow2) = a1.borrowing_sub(b1, borrow1);
2528        /// assert_eq!(borrow2, false);
2529        ///
2530        #[doc = concat!("assert_eq!((diff1, diff0), (3, ", stringify!($SelfT), "::MAX));")]
2531        /// ```
2532        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2533        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2534        #[must_use = "this returns the result of the operation, \
2535                      without modifying the original"]
2536        #[inline]
2537        pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) {
2538            // note: longer-term this should be done via an intrinsic, but this has been shown
2539            //   to generate optimal code for now, and LLVM doesn't have an equivalent intrinsic
2540            let (a, c1) = self.overflowing_sub(rhs);
2541            let (b, c2) = a.overflowing_sub(borrow as $SelfT);
2542            // SAFETY: Only one of `c1` and `c2` can be set.
2543            // For c1 to be set we need to have underflowed, but if we did then
2544            // `a` is nonzero, which means that `c2` cannot possibly
2545            // underflow because it's subtracting at most `1` (since it came from `bool`)
2546            (b, unsafe { intrinsics::disjoint_bitor(c1, c2) })
2547        }
2548
2549        /// Calculates `self` - `rhs` with a signed `rhs`
2550        ///
2551        /// Returns a tuple of the subtraction along with a boolean indicating
2552        /// whether an arithmetic overflow would occur. If an overflow would
2553        /// have occurred then the wrapped value is returned.
2554        ///
2555        /// # Examples
2556        ///
2557        /// ```
2558        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_signed(2), (", stringify!($SelfT), "::MAX, true));")]
2559        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_signed(-2), (3, false));")]
2560        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_sub_signed(-4), (1, true));")]
2561        /// ```
2562        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
2563        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "1.90.0")]
2564        #[must_use = "this returns the result of the operation, \
2565                      without modifying the original"]
2566        #[inline]
2567        pub const fn overflowing_sub_signed(self, rhs: $SignedT) -> (Self, bool) {
2568            let (res, overflow) = self.overflowing_sub(rhs as Self);
2569
2570            (res, overflow ^ (rhs < 0))
2571        }
2572
2573        /// Computes the absolute difference between `self` and `other`.
2574        ///
2575        /// # Examples
2576        ///
2577        /// ```
2578        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(80), 20", stringify!($SelfT), ");")]
2579        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(110), 10", stringify!($SelfT), ");")]
2580        /// ```
2581        #[stable(feature = "int_abs_diff", since = "1.60.0")]
2582        #[rustc_const_stable(feature = "int_abs_diff", since = "1.60.0")]
2583        #[must_use = "this returns the result of the operation, \
2584                      without modifying the original"]
2585        #[inline]
2586        pub const fn abs_diff(self, other: Self) -> Self {
2587            if size_of::<Self>() == 1 {
2588                // Trick LLVM into generating the psadbw instruction when SSE2
2589                // is available and this function is autovectorized for u8's.
2590                (self as i32).wrapping_sub(other as i32).unsigned_abs() as Self
2591            } else {
2592                if self < other {
2593                    other - self
2594                } else {
2595                    self - other
2596                }
2597            }
2598        }
2599
2600        /// Calculates the multiplication of `self` and `rhs`.
2601        ///
2602        /// Returns a tuple of the multiplication along with a boolean
2603        /// indicating whether an arithmetic overflow would occur. If an
2604        /// overflow would have occurred then the wrapped value is returned.
2605        ///
2606        /// # Examples
2607        ///
2608        /// Please note that this example is shared among integer types, which is why why `u32`
2609        /// is used.
2610        ///
2611        /// ```
2612        /// assert_eq!(5u32.overflowing_mul(2), (10, false));
2613        /// assert_eq!(1_000_000_000u32.overflowing_mul(10), (1410065408, true));
2614        /// ```
2615        #[stable(feature = "wrapping", since = "1.7.0")]
2616        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2617        #[must_use = "this returns the result of the operation, \
2618                          without modifying the original"]
2619        #[inline(always)]
2620        pub const fn overflowing_mul(self, rhs: Self) -> (Self, bool) {
2621            let (a, b) = intrinsics::mul_with_overflow(self as $ActualT, rhs as $ActualT);
2622            (a as Self, b)
2623        }
2624
2625        /// Calculates the complete product `self * rhs` without the possibility to overflow.
2626        ///
2627        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2628        /// of the result as two separate values, in that order.
2629        ///
2630        /// If you also need to add a carry to the wide result, then you want
2631        /// [`Self::carrying_mul`] instead.
2632        ///
2633        /// # Examples
2634        ///
2635        /// Please note that this example is shared among integer types, which is why `u32` is used.
2636        ///
2637        /// ```
2638        /// #![feature(bigint_helper_methods)]
2639        /// assert_eq!(5u32.widening_mul(2), (10, 0));
2640        /// assert_eq!(1_000_000_000u32.widening_mul(10), (1410065408, 2));
2641        /// ```
2642        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2643        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2644        #[must_use = "this returns the result of the operation, \
2645                      without modifying the original"]
2646        #[inline]
2647        pub const fn widening_mul(self, rhs: Self) -> (Self, Self) {
2648            Self::carrying_mul_add(self, rhs, 0, 0)
2649        }
2650
2651        /// Calculates the "full multiplication" `self * rhs + carry`
2652        /// without the possibility to overflow.
2653        ///
2654        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2655        /// of the result as two separate values, in that order.
2656        ///
2657        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2658        /// additional amount of overflow. This allows for chaining together multiple
2659        /// multiplications to create "big integers" which represent larger values.
2660        ///
2661        /// If you don't need the `carry`, then you can use [`Self::widening_mul`] instead.
2662        ///
2663        /// # Examples
2664        ///
2665        /// Please note that this example is shared among integer types, which is why `u32` is used.
2666        ///
2667        /// ```
2668        /// #![feature(bigint_helper_methods)]
2669        /// assert_eq!(5u32.carrying_mul(2, 0), (10, 0));
2670        /// assert_eq!(5u32.carrying_mul(2, 10), (20, 0));
2671        /// assert_eq!(1_000_000_000u32.carrying_mul(10, 0), (1410065408, 2));
2672        /// assert_eq!(1_000_000_000u32.carrying_mul(10, 10), (1410065418, 2));
2673        #[doc = concat!("assert_eq!(",
2674            stringify!($SelfT), "::MAX.carrying_mul(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2675            "(0, ", stringify!($SelfT), "::MAX));"
2676        )]
2677        /// ```
2678        ///
2679        /// This is the core operation needed for scalar multiplication when
2680        /// implementing it for wider-than-native types.
2681        ///
2682        /// ```
2683        /// #![feature(bigint_helper_methods)]
2684        /// fn scalar_mul_eq(little_endian_digits: &mut Vec<u16>, multiplicand: u16) {
2685        ///     let mut carry = 0;
2686        ///     for d in little_endian_digits.iter_mut() {
2687        ///         (*d, carry) = d.carrying_mul(multiplicand, carry);
2688        ///     }
2689        ///     if carry != 0 {
2690        ///         little_endian_digits.push(carry);
2691        ///     }
2692        /// }
2693        ///
2694        /// let mut v = vec![10, 20];
2695        /// scalar_mul_eq(&mut v, 3);
2696        /// assert_eq!(v, [30, 60]);
2697        ///
2698        /// assert_eq!(0x87654321_u64 * 0xFEED, 0x86D3D159E38D);
2699        /// let mut v = vec![0x4321, 0x8765];
2700        /// scalar_mul_eq(&mut v, 0xFEED);
2701        /// assert_eq!(v, [0xE38D, 0xD159, 0x86D3]);
2702        /// ```
2703        ///
2704        /// If `carry` is zero, this is similar to [`overflowing_mul`](Self::overflowing_mul),
2705        /// except that it gives the value of the overflow instead of just whether one happened:
2706        ///
2707        /// ```
2708        /// #![feature(bigint_helper_methods)]
2709        /// let r = u8::carrying_mul(7, 13, 0);
2710        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(7, 13));
2711        /// let r = u8::carrying_mul(13, 42, 0);
2712        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(13, 42));
2713        /// ```
2714        ///
2715        /// The value of the first field in the returned tuple matches what you'd get
2716        /// by combining the [`wrapping_mul`](Self::wrapping_mul) and
2717        /// [`wrapping_add`](Self::wrapping_add) methods:
2718        ///
2719        /// ```
2720        /// #![feature(bigint_helper_methods)]
2721        /// assert_eq!(
2722        ///     789_u16.carrying_mul(456, 123).0,
2723        ///     789_u16.wrapping_mul(456).wrapping_add(123),
2724        /// );
2725        /// ```
2726        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2727        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2728        #[must_use = "this returns the result of the operation, \
2729                      without modifying the original"]
2730        #[inline]
2731        pub const fn carrying_mul(self, rhs: Self, carry: Self) -> (Self, Self) {
2732            Self::carrying_mul_add(self, rhs, carry, 0)
2733        }
2734
2735        /// Calculates the "full multiplication" `self * rhs + carry1 + carry2`
2736        /// without the possibility to overflow.
2737        ///
2738        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2739        /// of the result as two separate values, in that order.
2740        ///
2741        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2742        /// additional amount of overflow. This allows for chaining together multiple
2743        /// multiplications to create "big integers" which represent larger values.
2744        ///
2745        /// If you don't need either `carry`, then you can use [`Self::widening_mul`] instead,
2746        /// and if you only need one `carry`, then you can use [`Self::carrying_mul`] instead.
2747        ///
2748        /// # Examples
2749        ///
2750        /// Please note that this example is shared between integer types,
2751        /// which explains why `u32` is used here.
2752        ///
2753        /// ```
2754        /// #![feature(bigint_helper_methods)]
2755        /// assert_eq!(5u32.carrying_mul_add(2, 0, 0), (10, 0));
2756        /// assert_eq!(5u32.carrying_mul_add(2, 10, 10), (30, 0));
2757        /// assert_eq!(1_000_000_000u32.carrying_mul_add(10, 0, 0), (1410065408, 2));
2758        /// assert_eq!(1_000_000_000u32.carrying_mul_add(10, 10, 10), (1410065428, 2));
2759        #[doc = concat!("assert_eq!(",
2760            stringify!($SelfT), "::MAX.carrying_mul_add(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2761            "(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX));"
2762        )]
2763        /// ```
2764        ///
2765        /// This is the core per-digit operation for "grade school" O(n²) multiplication.
2766        ///
2767        /// Please note that this example is shared between integer types,
2768        /// using `u8` for simplicity of the demonstration.
2769        ///
2770        /// ```
2771        /// #![feature(bigint_helper_methods)]
2772        ///
2773        /// fn quadratic_mul<const N: usize>(a: [u8; N], b: [u8; N]) -> [u8; N] {
2774        ///     let mut out = [0; N];
2775        ///     for j in 0..N {
2776        ///         let mut carry = 0;
2777        ///         for i in 0..(N - j) {
2778        ///             (out[j + i], carry) = u8::carrying_mul_add(a[i], b[j], out[j + i], carry);
2779        ///         }
2780        ///     }
2781        ///     out
2782        /// }
2783        ///
2784        /// // -1 * -1 == 1
2785        /// assert_eq!(quadratic_mul([0xFF; 3], [0xFF; 3]), [1, 0, 0]);
2786        ///
2787        /// assert_eq!(u32::wrapping_mul(0x9e3779b9, 0x7f4a7c15), 0xCFFC982D);
2788        /// assert_eq!(
2789        ///     quadratic_mul(u32::to_le_bytes(0x9e3779b9), u32::to_le_bytes(0x7f4a7c15)),
2790        ///     u32::to_le_bytes(0xCFFC982D)
2791        /// );
2792        /// ```
2793        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2794        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2795        #[must_use = "this returns the result of the operation, \
2796                      without modifying the original"]
2797        #[inline]
2798        pub const fn carrying_mul_add(self, rhs: Self, carry: Self, add: Self) -> (Self, Self) {
2799            intrinsics::carrying_mul_add(self, rhs, carry, add)
2800        }
2801
2802        /// Calculates the divisor when `self` is divided by `rhs`.
2803        ///
2804        /// Returns a tuple of the divisor along with a boolean indicating
2805        /// whether an arithmetic overflow would occur. Note that for unsigned
2806        /// integers overflow never occurs, so the second value is always
2807        /// `false`.
2808        ///
2809        /// # Panics
2810        ///
2811        /// This function will panic if `rhs` is zero.
2812        ///
2813        /// # Examples
2814        ///
2815        /// ```
2816        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div(2), (2, false));")]
2817        /// ```
2818        #[inline(always)]
2819        #[stable(feature = "wrapping", since = "1.7.0")]
2820        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2821        #[must_use = "this returns the result of the operation, \
2822                      without modifying the original"]
2823        #[track_caller]
2824        pub const fn overflowing_div(self, rhs: Self) -> (Self, bool) {
2825            (self / rhs, false)
2826        }
2827
2828        /// Calculates the quotient of Euclidean division `self.div_euclid(rhs)`.
2829        ///
2830        /// Returns a tuple of the divisor along with a boolean indicating
2831        /// whether an arithmetic overflow would occur. Note that for unsigned
2832        /// integers overflow never occurs, so the second value is always
2833        /// `false`.
2834        /// Since, for the positive integers, all common
2835        /// definitions of division are equal, this
2836        /// is exactly equal to `self.overflowing_div(rhs)`.
2837        ///
2838        /// # Panics
2839        ///
2840        /// This function will panic if `rhs` is zero.
2841        ///
2842        /// # Examples
2843        ///
2844        /// ```
2845        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));")]
2846        /// ```
2847        #[inline(always)]
2848        #[stable(feature = "euclidean_division", since = "1.38.0")]
2849        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2850        #[must_use = "this returns the result of the operation, \
2851                      without modifying the original"]
2852        #[track_caller]
2853        pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) {
2854            (self / rhs, false)
2855        }
2856
2857        /// Calculates the remainder when `self` is divided by `rhs`.
2858        ///
2859        /// Returns a tuple of the remainder after dividing along with a boolean
2860        /// indicating whether an arithmetic overflow would occur. Note that for
2861        /// unsigned integers overflow never occurs, so the second value is
2862        /// always `false`.
2863        ///
2864        /// # Panics
2865        ///
2866        /// This function will panic if `rhs` is zero.
2867        ///
2868        /// # Examples
2869        ///
2870        /// ```
2871        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")]
2872        /// ```
2873        #[inline(always)]
2874        #[stable(feature = "wrapping", since = "1.7.0")]
2875        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2876        #[must_use = "this returns the result of the operation, \
2877                      without modifying the original"]
2878        #[track_caller]
2879        pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) {
2880            (self % rhs, false)
2881        }
2882
2883        /// Calculates the remainder `self.rem_euclid(rhs)` as if by Euclidean division.
2884        ///
2885        /// Returns a tuple of the modulo after dividing along with a boolean
2886        /// indicating whether an arithmetic overflow would occur. Note that for
2887        /// unsigned integers overflow never occurs, so the second value is
2888        /// always `false`.
2889        /// Since, for the positive integers, all common
2890        /// definitions of division are equal, this operation
2891        /// is exactly equal to `self.overflowing_rem(rhs)`.
2892        ///
2893        /// # Panics
2894        ///
2895        /// This function will panic if `rhs` is zero.
2896        ///
2897        /// # Examples
2898        ///
2899        /// ```
2900        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")]
2901        /// ```
2902        #[inline(always)]
2903        #[stable(feature = "euclidean_division", since = "1.38.0")]
2904        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2905        #[must_use = "this returns the result of the operation, \
2906                      without modifying the original"]
2907        #[track_caller]
2908        pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) {
2909            (self % rhs, false)
2910        }
2911
2912        /// Negates self in an overflowing fashion.
2913        ///
2914        /// Returns `!self + 1` using wrapping operations to return the value
2915        /// that represents the negation of this unsigned value. Note that for
2916        /// positive unsigned values overflow always occurs, but negating 0 does
2917        /// not overflow.
2918        ///
2919        /// # Examples
2920        ///
2921        /// ```
2922        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_neg(), (0, false));")]
2923        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".overflowing_neg(), (-2i32 as ", stringify!($SelfT), ", true));")]
2924        /// ```
2925        #[inline(always)]
2926        #[stable(feature = "wrapping", since = "1.7.0")]
2927        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2928        #[must_use = "this returns the result of the operation, \
2929                      without modifying the original"]
2930        pub const fn overflowing_neg(self) -> (Self, bool) {
2931            ((!self).wrapping_add(1), self != 0)
2932        }
2933
2934        /// Shifts self left by `rhs` bits.
2935        ///
2936        /// Returns a tuple of the shifted version of self along with a boolean
2937        /// indicating whether the shift value was larger than or equal to the
2938        /// number of bits. If the shift value is too large, then value is
2939        /// masked (N-1) where N is the number of bits, and this value is then
2940        /// used to perform the shift.
2941        ///
2942        /// # Examples
2943        ///
2944        /// ```
2945        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(4), (0x10, false));")]
2946        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(132), (0x10, true));")]
2947        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shl(", stringify!($BITS_MINUS_ONE), "), (0, false));")]
2948        /// ```
2949        #[stable(feature = "wrapping", since = "1.7.0")]
2950        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2951        #[must_use = "this returns the result of the operation, \
2952                      without modifying the original"]
2953        #[inline(always)]
2954        pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) {
2955            (self.wrapping_shl(rhs), rhs >= Self::BITS)
2956        }
2957
2958        /// Shifts self right by `rhs` bits.
2959        ///
2960        /// Returns a tuple of the shifted version of self along with a boolean
2961        /// indicating whether the shift value was larger than or equal to the
2962        /// number of bits. If the shift value is too large, then value is
2963        /// masked (N-1) where N is the number of bits, and this value is then
2964        /// used to perform the shift.
2965        ///
2966        /// # Examples
2967        ///
2968        /// ```
2969        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(4), (0x1, false));")]
2970        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(132), (0x1, true));")]
2971        /// ```
2972        #[stable(feature = "wrapping", since = "1.7.0")]
2973        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2974        #[must_use = "this returns the result of the operation, \
2975                      without modifying the original"]
2976        #[inline(always)]
2977        pub const fn overflowing_shr(self, rhs: u32) -> (Self, bool) {
2978            (self.wrapping_shr(rhs), rhs >= Self::BITS)
2979        }
2980
2981        /// Raises self to the power of `exp`, using exponentiation by squaring.
2982        ///
2983        /// Returns a tuple of the exponentiation along with a bool indicating
2984        /// whether an overflow happened.
2985        ///
2986        /// # Examples
2987        ///
2988        /// ```
2989        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".overflowing_pow(5), (243, false));")]
2990        /// assert_eq!(3u8.overflowing_pow(6), (217, true));
2991        /// ```
2992        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2993        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2994        #[must_use = "this returns the result of the operation, \
2995                      without modifying the original"]
2996        #[inline]
2997        pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) {
2998            if exp == 0{
2999                return (1,false);
3000            }
3001            let mut base = self;
3002            let mut acc: Self = 1;
3003            let mut overflown = false;
3004            // Scratch space for storing results of overflowing_mul.
3005            let mut r;
3006
3007            loop {
3008                if (exp & 1) == 1 {
3009                    r = acc.overflowing_mul(base);
3010                    // since exp!=0, finally the exp must be 1.
3011                    if exp == 1 {
3012                        r.1 |= overflown;
3013                        return r;
3014                    }
3015                    acc = r.0;
3016                    overflown |= r.1;
3017                }
3018                exp /= 2;
3019                r = base.overflowing_mul(base);
3020                base = r.0;
3021                overflown |= r.1;
3022            }
3023        }
3024
3025        /// Raises self to the power of `exp`, using exponentiation by squaring.
3026        ///
3027        /// # Examples
3028        ///
3029        /// ```
3030        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".pow(5), 32);")]
3031        /// ```
3032        #[stable(feature = "rust1", since = "1.0.0")]
3033        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3034        #[must_use = "this returns the result of the operation, \
3035                      without modifying the original"]
3036        #[inline]
3037        #[rustc_inherit_overflow_checks]
3038        pub const fn pow(self, mut exp: u32) -> Self {
3039            if exp == 0 {
3040                return 1;
3041            }
3042            let mut base = self;
3043            let mut acc = 1;
3044
3045            if intrinsics::is_val_statically_known(exp) {
3046                while exp > 1 {
3047                    if (exp & 1) == 1 {
3048                        acc = acc * base;
3049                    }
3050                    exp /= 2;
3051                    base = base * base;
3052                }
3053
3054                // since exp!=0, finally the exp must be 1.
3055                // Deal with the final bit of the exponent separately, since
3056                // squaring the base afterwards is not necessary and may cause a
3057                // needless overflow.
3058                acc * base
3059            } else {
3060                // This is faster than the above when the exponent is not known
3061                // at compile time. We can't use the same code for the constant
3062                // exponent case because LLVM is currently unable to unroll
3063                // this loop.
3064                loop {
3065                    if (exp & 1) == 1 {
3066                        acc = acc * base;
3067                        // since exp!=0, finally the exp must be 1.
3068                        if exp == 1 {
3069                            return acc;
3070                        }
3071                    }
3072                    exp /= 2;
3073                    base = base * base;
3074                }
3075            }
3076        }
3077
3078        /// Returns the square root of the number, rounded down.
3079        ///
3080        /// # Examples
3081        ///
3082        /// ```
3083        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".isqrt(), 3);")]
3084        /// ```
3085        #[stable(feature = "isqrt", since = "1.84.0")]
3086        #[rustc_const_stable(feature = "isqrt", since = "1.84.0")]
3087        #[must_use = "this returns the result of the operation, \
3088                      without modifying the original"]
3089        #[inline]
3090        pub const fn isqrt(self) -> Self {
3091            let result = crate::num::int_sqrt::$ActualT(self as $ActualT) as $SelfT;
3092
3093            // Inform the optimizer what the range of outputs is. If testing
3094            // `core` crashes with no panic message and a `num::int_sqrt::u*`
3095            // test failed, it's because your edits caused these assertions or
3096            // the assertions in `fn isqrt` of `nonzero.rs` to become false.
3097            //
3098            // SAFETY: Integer square root is a monotonically nondecreasing
3099            // function, which means that increasing the input will never
3100            // cause the output to decrease. Thus, since the input for unsigned
3101            // integers is bounded by `[0, <$ActualT>::MAX]`, sqrt(n) will be
3102            // bounded by `[sqrt(0), sqrt(<$ActualT>::MAX)]`.
3103            unsafe {
3104                const MAX_RESULT: $SelfT = crate::num::int_sqrt::$ActualT(<$ActualT>::MAX) as $SelfT;
3105                crate::hint::assert_unchecked(result <= MAX_RESULT);
3106            }
3107
3108            result
3109        }
3110
3111        /// Performs Euclidean division.
3112        ///
3113        /// Since, for the positive integers, all common
3114        /// definitions of division are equal, this
3115        /// is exactly equal to `self / rhs`.
3116        ///
3117        /// # Panics
3118        ///
3119        /// This function will panic if `rhs` is zero.
3120        ///
3121        /// # Examples
3122        ///
3123        /// ```
3124        #[doc = concat!("assert_eq!(7", stringify!($SelfT), ".div_euclid(4), 1); // or any other integer type")]
3125        /// ```
3126        #[stable(feature = "euclidean_division", since = "1.38.0")]
3127        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3128        #[must_use = "this returns the result of the operation, \
3129                      without modifying the original"]
3130        #[inline(always)]
3131        #[track_caller]
3132        pub const fn div_euclid(self, rhs: Self) -> Self {
3133            self / rhs
3134        }
3135
3136
3137        /// Calculates the least remainder of `self (mod rhs)`.
3138        ///
3139        /// Since, for the positive integers, all common
3140        /// definitions of division are equal, this
3141        /// is exactly equal to `self % rhs`.
3142        ///
3143        /// # Panics
3144        ///
3145        /// This function will panic if `rhs` is zero.
3146        ///
3147        /// # Examples
3148        ///
3149        /// ```
3150        #[doc = concat!("assert_eq!(7", stringify!($SelfT), ".rem_euclid(4), 3); // or any other integer type")]
3151        /// ```
3152        #[doc(alias = "modulo", alias = "mod")]
3153        #[stable(feature = "euclidean_division", since = "1.38.0")]
3154        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3155        #[must_use = "this returns the result of the operation, \
3156                      without modifying the original"]
3157        #[inline(always)]
3158        #[track_caller]
3159        pub const fn rem_euclid(self, rhs: Self) -> Self {
3160            self % rhs
3161        }
3162
3163        /// Calculates the quotient of `self` and `rhs`, rounding the result towards negative infinity.
3164        ///
3165        /// This is the same as performing `self / rhs` for all unsigned integers.
3166        ///
3167        /// # Panics
3168        ///
3169        /// This function will panic if `rhs` is zero.
3170        ///
3171        /// # Examples
3172        ///
3173        /// ```
3174        /// #![feature(int_roundings)]
3175        #[doc = concat!("assert_eq!(7_", stringify!($SelfT), ".div_floor(4), 1);")]
3176        /// ```
3177        #[unstable(feature = "int_roundings", issue = "88581")]
3178        #[must_use = "this returns the result of the operation, \
3179                      without modifying the original"]
3180        #[inline(always)]
3181        #[track_caller]
3182        pub const fn div_floor(self, rhs: Self) -> Self {
3183            self / rhs
3184        }
3185
3186        /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity.
3187        ///
3188        /// # Panics
3189        ///
3190        /// This function will panic if `rhs` is zero.
3191        ///
3192        /// # Examples
3193        ///
3194        /// ```
3195        #[doc = concat!("assert_eq!(7_", stringify!($SelfT), ".div_ceil(4), 2);")]
3196        /// ```
3197        #[stable(feature = "int_roundings1", since = "1.73.0")]
3198        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3199        #[must_use = "this returns the result of the operation, \
3200                      without modifying the original"]
3201        #[inline]
3202        #[track_caller]
3203        pub const fn div_ceil(self, rhs: Self) -> Self {
3204            let d = self / rhs;
3205            let r = self % rhs;
3206            if r > 0 {
3207                d + 1
3208            } else {
3209                d
3210            }
3211        }
3212
3213        /// Calculates the smallest value greater than or equal to `self` that
3214        /// is a multiple of `rhs`.
3215        ///
3216        /// # Panics
3217        ///
3218        /// This function will panic if `rhs` is zero.
3219        ///
3220        /// ## Overflow behavior
3221        ///
3222        /// On overflow, this function will panic if overflow checks are enabled (default in debug
3223        /// mode) and wrap if overflow checks are disabled (default in release mode).
3224        ///
3225        /// # Examples
3226        ///
3227        /// ```
3228        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(8), 16);")]
3229        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(8), 24);")]
3230        /// ```
3231        #[stable(feature = "int_roundings1", since = "1.73.0")]
3232        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3233        #[must_use = "this returns the result of the operation, \
3234                      without modifying the original"]
3235        #[inline]
3236        #[rustc_inherit_overflow_checks]
3237        pub const fn next_multiple_of(self, rhs: Self) -> Self {
3238            match self % rhs {
3239                0 => self,
3240                r => self + (rhs - r)
3241            }
3242        }
3243
3244        /// Calculates the smallest value greater than or equal to `self` that
3245        /// is a multiple of `rhs`. Returns `None` if `rhs` is zero or the
3246        /// operation would result in overflow.
3247        ///
3248        /// # Examples
3249        ///
3250        /// ```
3251        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(16));")]
3252        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(24));")]
3253        #[doc = concat!("assert_eq!(1_", stringify!($SelfT), ".checked_next_multiple_of(0), None);")]
3254        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_multiple_of(2), None);")]
3255        /// ```
3256        #[stable(feature = "int_roundings1", since = "1.73.0")]
3257        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3258        #[must_use = "this returns the result of the operation, \
3259                      without modifying the original"]
3260        #[inline]
3261        pub const fn checked_next_multiple_of(self, rhs: Self) -> Option<Self> {
3262            match try_opt!(self.checked_rem(rhs)) {
3263                0 => Some(self),
3264                // rhs - r cannot overflow because r is smaller than rhs
3265                r => self.checked_add(rhs - r)
3266            }
3267        }
3268
3269        /// Returns `true` if `self` is an integer multiple of `rhs`, and false otherwise.
3270        ///
3271        /// This function is equivalent to `self % rhs == 0`, except that it will not panic
3272        /// for `rhs == 0`. Instead, `0.is_multiple_of(0) == true`, and for any non-zero `n`,
3273        /// `n.is_multiple_of(0) == false`.
3274        ///
3275        /// # Examples
3276        ///
3277        /// ```
3278        #[doc = concat!("assert!(6_", stringify!($SelfT), ".is_multiple_of(2));")]
3279        #[doc = concat!("assert!(!5_", stringify!($SelfT), ".is_multiple_of(2));")]
3280        ///
3281        #[doc = concat!("assert!(0_", stringify!($SelfT), ".is_multiple_of(0));")]
3282        #[doc = concat!("assert!(!6_", stringify!($SelfT), ".is_multiple_of(0));")]
3283        /// ```
3284        #[stable(feature = "unsigned_is_multiple_of", since = "1.87.0")]
3285        #[rustc_const_stable(feature = "unsigned_is_multiple_of", since = "1.87.0")]
3286        #[must_use]
3287        #[inline]
3288        #[rustc_inherit_overflow_checks]
3289        pub const fn is_multiple_of(self, rhs: Self) -> bool {
3290            match rhs {
3291                0 => self == 0,
3292                _ => self % rhs == 0,
3293            }
3294        }
3295
3296        /// Returns `true` if and only if `self == 2^k` for some unsigned integer `k`.
3297        ///
3298        /// # Examples
3299        ///
3300        /// ```
3301        #[doc = concat!("assert!(16", stringify!($SelfT), ".is_power_of_two());")]
3302        #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_power_of_two());")]
3303        /// ```
3304        #[must_use]
3305        #[stable(feature = "rust1", since = "1.0.0")]
3306        #[rustc_const_stable(feature = "const_is_power_of_two", since = "1.32.0")]
3307        #[inline(always)]
3308        pub const fn is_power_of_two(self) -> bool {
3309            self.count_ones() == 1
3310        }
3311
3312        // Returns one less than next power of two.
3313        // (For 8u8 next power of two is 8u8 and for 6u8 it is 8u8)
3314        //
3315        // 8u8.one_less_than_next_power_of_two() == 7
3316        // 6u8.one_less_than_next_power_of_two() == 7
3317        //
3318        // This method cannot overflow, as in the `next_power_of_two`
3319        // overflow cases it instead ends up returning the maximum value
3320        // of the type, and can return 0 for 0.
3321        #[inline]
3322        const fn one_less_than_next_power_of_two(self) -> Self {
3323            if self <= 1 { return 0; }
3324
3325            let p = self - 1;
3326            // SAFETY: Because `p > 0`, it cannot consist entirely of leading zeros.
3327            // That means the shift is always in-bounds, and some processors
3328            // (such as intel pre-haswell) have more efficient ctlz
3329            // intrinsics when the argument is non-zero.
3330            let z = unsafe { intrinsics::ctlz_nonzero(p) };
3331            <$SelfT>::MAX >> z
3332        }
3333
3334        /// Returns the smallest power of two greater than or equal to `self`.
3335        ///
3336        /// When return value overflows (i.e., `self > (1 << (N-1))` for type
3337        /// `uN`), it panics in debug mode and the return value is wrapped to 0 in
3338        /// release mode (the only situation in which this method can return 0).
3339        ///
3340        /// # Examples
3341        ///
3342        /// ```
3343        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".next_power_of_two(), 2);")]
3344        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".next_power_of_two(), 4);")]
3345        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".next_power_of_two(), 1);")]
3346        /// ```
3347        #[stable(feature = "rust1", since = "1.0.0")]
3348        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3349        #[must_use = "this returns the result of the operation, \
3350                      without modifying the original"]
3351        #[inline]
3352        #[rustc_inherit_overflow_checks]
3353        pub const fn next_power_of_two(self) -> Self {
3354            self.one_less_than_next_power_of_two() + 1
3355        }
3356
3357        /// Returns the smallest power of two greater than or equal to `self`. If
3358        /// the next power of two is greater than the type's maximum value,
3359        /// `None` is returned, otherwise the power of two is wrapped in `Some`.
3360        ///
3361        /// # Examples
3362        ///
3363        /// ```
3364        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_next_power_of_two(), Some(2));")]
3365        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".checked_next_power_of_two(), Some(4));")]
3366        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_power_of_two(), None);")]
3367        /// ```
3368        #[inline]
3369        #[stable(feature = "rust1", since = "1.0.0")]
3370        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3371        #[must_use = "this returns the result of the operation, \
3372                      without modifying the original"]
3373        pub const fn checked_next_power_of_two(self) -> Option<Self> {
3374            self.one_less_than_next_power_of_two().checked_add(1)
3375        }
3376
3377        /// Returns the smallest power of two greater than or equal to `n`. If
3378        /// the next power of two is greater than the type's maximum value,
3379        /// the return value is wrapped to `0`.
3380        ///
3381        /// # Examples
3382        ///
3383        /// ```
3384        /// #![feature(wrapping_next_power_of_two)]
3385        ///
3386        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".wrapping_next_power_of_two(), 2);")]
3387        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_next_power_of_two(), 4);")]
3388        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_next_power_of_two(), 0);")]
3389        /// ```
3390        #[inline]
3391        #[unstable(feature = "wrapping_next_power_of_two", issue = "32463",
3392                   reason = "needs decision on wrapping behavior")]
3393        #[must_use = "this returns the result of the operation, \
3394                      without modifying the original"]
3395        pub const fn wrapping_next_power_of_two(self) -> Self {
3396            self.one_less_than_next_power_of_two().wrapping_add(1)
3397        }
3398
3399        /// Returns the memory representation of this integer as a byte array in
3400        /// big-endian (network) byte order.
3401        ///
3402        #[doc = $to_xe_bytes_doc]
3403        ///
3404        /// # Examples
3405        ///
3406        /// ```
3407        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_be_bytes();")]
3408        #[doc = concat!("assert_eq!(bytes, ", $be_bytes, ");")]
3409        /// ```
3410        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3411        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3412        #[must_use = "this returns the result of the operation, \
3413                      without modifying the original"]
3414        #[inline]
3415        pub const fn to_be_bytes(self) -> [u8; size_of::<Self>()] {
3416            self.to_be().to_ne_bytes()
3417        }
3418
3419        /// Returns the memory representation of this integer as a byte array in
3420        /// little-endian byte order.
3421        ///
3422        #[doc = $to_xe_bytes_doc]
3423        ///
3424        /// # Examples
3425        ///
3426        /// ```
3427        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_le_bytes();")]
3428        #[doc = concat!("assert_eq!(bytes, ", $le_bytes, ");")]
3429        /// ```
3430        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3431        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3432        #[must_use = "this returns the result of the operation, \
3433                      without modifying the original"]
3434        #[inline]
3435        pub const fn to_le_bytes(self) -> [u8; size_of::<Self>()] {
3436            self.to_le().to_ne_bytes()
3437        }
3438
3439        /// Returns the memory representation of this integer as a byte array in
3440        /// native byte order.
3441        ///
3442        /// As the target platform's native endianness is used, portable code
3443        /// should use [`to_be_bytes`] or [`to_le_bytes`], as appropriate,
3444        /// instead.
3445        ///
3446        #[doc = $to_xe_bytes_doc]
3447        ///
3448        /// [`to_be_bytes`]: Self::to_be_bytes
3449        /// [`to_le_bytes`]: Self::to_le_bytes
3450        ///
3451        /// # Examples
3452        ///
3453        /// ```
3454        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_ne_bytes();")]
3455        /// assert_eq!(
3456        ///     bytes,
3457        ///     if cfg!(target_endian = "big") {
3458        #[doc = concat!("        ", $be_bytes)]
3459        ///     } else {
3460        #[doc = concat!("        ", $le_bytes)]
3461        ///     }
3462        /// );
3463        /// ```
3464        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3465        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3466        #[must_use = "this returns the result of the operation, \
3467                      without modifying the original"]
3468        #[allow(unnecessary_transmutes)]
3469        // SAFETY: const sound because integers are plain old datatypes so we can always
3470        // transmute them to arrays of bytes
3471        #[inline]
3472        pub const fn to_ne_bytes(self) -> [u8; size_of::<Self>()] {
3473            // SAFETY: integers are plain old datatypes so we can always transmute them to
3474            // arrays of bytes
3475            unsafe { mem::transmute(self) }
3476        }
3477
3478        /// Creates a native endian integer value from its representation
3479        /// as a byte array in big endian.
3480        ///
3481        #[doc = $from_xe_bytes_doc]
3482        ///
3483        /// # Examples
3484        ///
3485        /// ```
3486        #[doc = concat!("let value = ", stringify!($SelfT), "::from_be_bytes(", $be_bytes, ");")]
3487        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3488        /// ```
3489        ///
3490        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3491        ///
3492        /// ```
3493        #[doc = concat!("fn read_be_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3494        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3495        ///     *input = rest;
3496        #[doc = concat!("    ", stringify!($SelfT), "::from_be_bytes(int_bytes.try_into().unwrap())")]
3497        /// }
3498        /// ```
3499        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3500        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3501        #[must_use]
3502        #[inline]
3503        pub const fn from_be_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3504            Self::from_be(Self::from_ne_bytes(bytes))
3505        }
3506
3507        /// Creates a native endian integer value from its representation
3508        /// as a byte array in little endian.
3509        ///
3510        #[doc = $from_xe_bytes_doc]
3511        ///
3512        /// # Examples
3513        ///
3514        /// ```
3515        #[doc = concat!("let value = ", stringify!($SelfT), "::from_le_bytes(", $le_bytes, ");")]
3516        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3517        /// ```
3518        ///
3519        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3520        ///
3521        /// ```
3522        #[doc = concat!("fn read_le_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3523        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3524        ///     *input = rest;
3525        #[doc = concat!("    ", stringify!($SelfT), "::from_le_bytes(int_bytes.try_into().unwrap())")]
3526        /// }
3527        /// ```
3528        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3529        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3530        #[must_use]
3531        #[inline]
3532        pub const fn from_le_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3533            Self::from_le(Self::from_ne_bytes(bytes))
3534        }
3535
3536        /// Creates a native endian integer value from its memory representation
3537        /// as a byte array in native endianness.
3538        ///
3539        /// As the target platform's native endianness is used, portable code
3540        /// likely wants to use [`from_be_bytes`] or [`from_le_bytes`], as
3541        /// appropriate instead.
3542        ///
3543        /// [`from_be_bytes`]: Self::from_be_bytes
3544        /// [`from_le_bytes`]: Self::from_le_bytes
3545        ///
3546        #[doc = $from_xe_bytes_doc]
3547        ///
3548        /// # Examples
3549        ///
3550        /// ```
3551        #[doc = concat!("let value = ", stringify!($SelfT), "::from_ne_bytes(if cfg!(target_endian = \"big\") {")]
3552        #[doc = concat!("    ", $be_bytes, "")]
3553        /// } else {
3554        #[doc = concat!("    ", $le_bytes, "")]
3555        /// });
3556        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3557        /// ```
3558        ///
3559        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3560        ///
3561        /// ```
3562        #[doc = concat!("fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3563        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3564        ///     *input = rest;
3565        #[doc = concat!("    ", stringify!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())")]
3566        /// }
3567        /// ```
3568        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3569        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3570        #[allow(unnecessary_transmutes)]
3571        #[must_use]
3572        // SAFETY: const sound because integers are plain old datatypes so we can always
3573        // transmute to them
3574        #[inline]
3575        pub const fn from_ne_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3576            // SAFETY: integers are plain old datatypes so we can always transmute to them
3577            unsafe { mem::transmute(bytes) }
3578        }
3579
3580        /// New code should prefer to use
3581        #[doc = concat!("[`", stringify!($SelfT), "::MIN", "`] instead.")]
3582        ///
3583        /// Returns the smallest value that can be represented by this integer type.
3584        #[stable(feature = "rust1", since = "1.0.0")]
3585        #[rustc_promotable]
3586        #[inline(always)]
3587        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3588        #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")]
3589        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value")]
3590        pub const fn min_value() -> Self { Self::MIN }
3591
3592        /// New code should prefer to use
3593        #[doc = concat!("[`", stringify!($SelfT), "::MAX", "`] instead.")]
3594        ///
3595        /// Returns the largest value that can be represented by this integer type.
3596        #[stable(feature = "rust1", since = "1.0.0")]
3597        #[rustc_promotable]
3598        #[inline(always)]
3599        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3600        #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")]
3601        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value")]
3602        pub const fn max_value() -> Self { Self::MAX }
3603    }
3604}