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!($SelfT), " = 0b_01100100;")]
231        ///
232        /// assert_eq!(n.isolate_most_significant_one(), 0b_01000000);
233        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_most_significant_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_most_significant_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!($SelfT), " = 0b_01100100;")]
252        ///
253        /// assert_eq!(n.isolate_least_significant_one(), 0b_00000100);
254        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_least_significant_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_least_significant_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        /// #![feature(strict_overflow_ops)]
542        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).strict_add(1), ", stringify!($SelfT), "::MAX - 1);")]
543        /// ```
544        ///
545        /// The following panics because of overflow:
546        ///
547        /// ```should_panic
548        /// #![feature(strict_overflow_ops)]
549        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add(3);")]
550        /// ```
551        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
552        #[must_use = "this returns the result of the operation, \
553                      without modifying the original"]
554        #[inline]
555        #[track_caller]
556        pub const fn strict_add(self, rhs: Self) -> Self {
557            let (a, b) = self.overflowing_add(rhs);
558            if b { overflow_panic::add() } else { a }
559         }
560
561        /// Unchecked integer addition. Computes `self + rhs`, assuming overflow
562        /// cannot occur.
563        ///
564        /// Calling `x.unchecked_add(y)` is semantically equivalent to calling
565        /// `x.`[`checked_add`]`(y).`[`unwrap_unchecked`]`()`.
566        ///
567        /// If you're just trying to avoid the panic in debug mode, then **do not**
568        /// use this.  Instead, you're looking for [`wrapping_add`].
569        ///
570        /// # Safety
571        ///
572        /// This results in undefined behavior when
573        #[doc = concat!("`self + rhs > ", stringify!($SelfT), "::MAX` or `self + rhs < ", stringify!($SelfT), "::MIN`,")]
574        /// i.e. when [`checked_add`] would return `None`.
575        ///
576        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
577        #[doc = concat!("[`checked_add`]: ", stringify!($SelfT), "::checked_add")]
578        #[doc = concat!("[`wrapping_add`]: ", stringify!($SelfT), "::wrapping_add")]
579        #[stable(feature = "unchecked_math", since = "1.79.0")]
580        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
581        #[must_use = "this returns the result of the operation, \
582                      without modifying the original"]
583        #[inline(always)]
584        #[track_caller]
585        pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
586            assert_unsafe_precondition!(
587                check_language_ub,
588                concat!(stringify!($SelfT), "::unchecked_add cannot overflow"),
589                (
590                    lhs: $SelfT = self,
591                    rhs: $SelfT = rhs,
592                ) => !lhs.overflowing_add(rhs).1,
593            );
594
595            // SAFETY: this is guaranteed to be safe by the caller.
596            unsafe {
597                intrinsics::unchecked_add(self, rhs)
598            }
599        }
600
601        /// Checked addition with a signed integer. Computes `self + rhs`,
602        /// returning `None` if overflow occurred.
603        ///
604        /// # Examples
605        ///
606        /// ```
607        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(2), Some(3));")]
608        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(-2), None);")]
609        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_signed(3), None);")]
610        /// ```
611        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
612        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
613        #[must_use = "this returns the result of the operation, \
614                      without modifying the original"]
615        #[inline]
616        pub const fn checked_add_signed(self, rhs: $SignedT) -> Option<Self> {
617            let (a, b) = self.overflowing_add_signed(rhs);
618            if intrinsics::unlikely(b) { None } else { Some(a) }
619        }
620
621        /// Strict addition with a signed integer. Computes `self + rhs`,
622        /// panicking if overflow occurred.
623        ///
624        /// # Panics
625        ///
626        /// ## Overflow behavior
627        ///
628        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
629        ///
630        /// # Examples
631        ///
632        /// ```
633        /// #![feature(strict_overflow_ops)]
634        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_add_signed(2), 3);")]
635        /// ```
636        ///
637        /// The following panic because of overflow:
638        ///
639        /// ```should_panic
640        /// #![feature(strict_overflow_ops)]
641        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_add_signed(-2);")]
642        /// ```
643        ///
644        /// ```should_panic
645        /// #![feature(strict_overflow_ops)]
646        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add_signed(3);")]
647        /// ```
648        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
649        #[must_use = "this returns the result of the operation, \
650                      without modifying the original"]
651        #[inline]
652        #[track_caller]
653        pub const fn strict_add_signed(self, rhs: $SignedT) -> Self {
654            let (a, b) = self.overflowing_add_signed(rhs);
655            if b { overflow_panic::add() } else { a }
656         }
657
658        /// Checked integer subtraction. Computes `self - rhs`, returning
659        /// `None` if overflow occurred.
660        ///
661        /// # Examples
662        ///
663        /// ```
664        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub(1), Some(0));")]
665        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".checked_sub(1), None);")]
666        /// ```
667        #[stable(feature = "rust1", since = "1.0.0")]
668        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
669        #[must_use = "this returns the result of the operation, \
670                      without modifying the original"]
671        #[inline]
672        pub const fn checked_sub(self, rhs: Self) -> Option<Self> {
673            // Per PR#103299, there's no advantage to the `overflowing` intrinsic
674            // for *unsigned* subtraction and we just emit the manual check anyway.
675            // Thus, rather than using `overflowing_sub` that produces a wrapping
676            // subtraction, check it ourself so we can use an unchecked one.
677
678            if self < rhs {
679                None
680            } else {
681                // SAFETY: just checked this can't overflow
682                Some(unsafe { intrinsics::unchecked_sub(self, rhs) })
683            }
684        }
685
686        /// Strict integer subtraction. Computes `self - rhs`, panicking if
687        /// overflow occurred.
688        ///
689        /// # Panics
690        ///
691        /// ## Overflow behavior
692        ///
693        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
694        ///
695        /// # Examples
696        ///
697        /// ```
698        /// #![feature(strict_overflow_ops)]
699        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_sub(1), 0);")]
700        /// ```
701        ///
702        /// The following panics because of overflow:
703        ///
704        /// ```should_panic
705        /// #![feature(strict_overflow_ops)]
706        #[doc = concat!("let _ = 0", stringify!($SelfT), ".strict_sub(1);")]
707        /// ```
708        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
709        #[must_use = "this returns the result of the operation, \
710                      without modifying the original"]
711        #[inline]
712        #[track_caller]
713        pub const fn strict_sub(self, rhs: Self) -> Self {
714            let (a, b) = self.overflowing_sub(rhs);
715            if b { overflow_panic::sub() } else { a }
716         }
717
718        /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow
719        /// cannot occur.
720        ///
721        /// Calling `x.unchecked_sub(y)` is semantically equivalent to calling
722        /// `x.`[`checked_sub`]`(y).`[`unwrap_unchecked`]`()`.
723        ///
724        /// If you're just trying to avoid the panic in debug mode, then **do not**
725        /// use this.  Instead, you're looking for [`wrapping_sub`].
726        ///
727        /// If you find yourself writing code like this:
728        ///
729        /// ```
730        /// # let foo = 30_u32;
731        /// # let bar = 20;
732        /// if foo >= bar {
733        ///     // SAFETY: just checked it will not overflow
734        ///     let diff = unsafe { foo.unchecked_sub(bar) };
735        ///     // ... use diff ...
736        /// }
737        /// ```
738        ///
739        /// Consider changing it to
740        ///
741        /// ```
742        /// # let foo = 30_u32;
743        /// # let bar = 20;
744        /// if let Some(diff) = foo.checked_sub(bar) {
745        ///     // ... use diff ...
746        /// }
747        /// ```
748        ///
749        /// As that does exactly the same thing -- including telling the optimizer
750        /// that the subtraction cannot overflow -- but avoids needing `unsafe`.
751        ///
752        /// # Safety
753        ///
754        /// This results in undefined behavior when
755        #[doc = concat!("`self - rhs > ", stringify!($SelfT), "::MAX` or `self - rhs < ", stringify!($SelfT), "::MIN`,")]
756        /// i.e. when [`checked_sub`] would return `None`.
757        ///
758        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
759        #[doc = concat!("[`checked_sub`]: ", stringify!($SelfT), "::checked_sub")]
760        #[doc = concat!("[`wrapping_sub`]: ", stringify!($SelfT), "::wrapping_sub")]
761        #[stable(feature = "unchecked_math", since = "1.79.0")]
762        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
763        #[must_use = "this returns the result of the operation, \
764                      without modifying the original"]
765        #[inline(always)]
766        #[track_caller]
767        pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
768            assert_unsafe_precondition!(
769                check_language_ub,
770                concat!(stringify!($SelfT), "::unchecked_sub cannot overflow"),
771                (
772                    lhs: $SelfT = self,
773                    rhs: $SelfT = rhs,
774                ) => !lhs.overflowing_sub(rhs).1,
775            );
776
777            // SAFETY: this is guaranteed to be safe by the caller.
778            unsafe {
779                intrinsics::unchecked_sub(self, rhs)
780            }
781        }
782
783        /// Checked subtraction with a signed integer. Computes `self - rhs`,
784        /// returning `None` if overflow occurred.
785        ///
786        /// # Examples
787        ///
788        /// ```
789        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_signed(2), None);")]
790        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_signed(-2), Some(3));")]
791        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_sub_signed(-4), None);")]
792        /// ```
793        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
794        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
795        #[must_use = "this returns the result of the operation, \
796                      without modifying the original"]
797        #[inline]
798        pub const fn checked_sub_signed(self, rhs: $SignedT) -> Option<Self> {
799            let (res, overflow) = self.overflowing_sub_signed(rhs);
800
801            if !overflow {
802                Some(res)
803            } else {
804                None
805            }
806        }
807
808        #[doc = concat!(
809            "Checked integer subtraction. Computes `self - rhs` and checks if the result fits into an [`",
810            stringify!($SignedT), "`], returning `None` if overflow occurred."
811        )]
812        ///
813        /// # Examples
814        ///
815        /// ```
816        /// #![feature(unsigned_signed_diff)]
817        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_signed_diff(2), Some(8));")]
818        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_signed_diff(10), Some(-8));")]
819        #[doc = concat!(
820            "assert_eq!(",
821            stringify!($SelfT),
822            "::MAX.checked_signed_diff(",
823            stringify!($SignedT),
824            "::MAX as ",
825            stringify!($SelfT),
826            "), None);"
827        )]
828        #[doc = concat!(
829            "assert_eq!((",
830            stringify!($SignedT),
831            "::MAX as ",
832            stringify!($SelfT),
833            ").checked_signed_diff(",
834            stringify!($SelfT),
835            "::MAX), Some(",
836            stringify!($SignedT),
837            "::MIN));"
838        )]
839        #[doc = concat!(
840            "assert_eq!((",
841            stringify!($SignedT),
842            "::MAX as ",
843            stringify!($SelfT),
844            " + 1).checked_signed_diff(0), None);"
845        )]
846        #[doc = concat!(
847            "assert_eq!(",
848            stringify!($SelfT),
849            "::MAX.checked_signed_diff(",
850            stringify!($SelfT),
851            "::MAX), Some(0));"
852        )]
853        /// ```
854        #[unstable(feature = "unsigned_signed_diff", issue = "126041")]
855        #[inline]
856        pub const fn checked_signed_diff(self, rhs: Self) -> Option<$SignedT> {
857            let res = self.wrapping_sub(rhs) as $SignedT;
858            let overflow = (self >= rhs) == (res < 0);
859
860            if !overflow {
861                Some(res)
862            } else {
863                None
864            }
865        }
866
867        /// Checked integer multiplication. Computes `self * rhs`, returning
868        /// `None` if overflow occurred.
869        ///
870        /// # Examples
871        ///
872        /// ```
873        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_mul(1), Some(5));")]
874        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);")]
875        /// ```
876        #[stable(feature = "rust1", since = "1.0.0")]
877        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
878        #[must_use = "this returns the result of the operation, \
879                      without modifying the original"]
880        #[inline]
881        pub const fn checked_mul(self, rhs: Self) -> Option<Self> {
882            let (a, b) = self.overflowing_mul(rhs);
883            if intrinsics::unlikely(b) { None } else { Some(a) }
884        }
885
886        /// Strict integer multiplication. Computes `self * rhs`, panicking if
887        /// overflow occurred.
888        ///
889        /// # Panics
890        ///
891        /// ## Overflow behavior
892        ///
893        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
894        ///
895        /// # Examples
896        ///
897        /// ```
898        /// #![feature(strict_overflow_ops)]
899        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_mul(1), 5);")]
900        /// ```
901        ///
902        /// The following panics because of overflow:
903        ///
904        /// ``` should_panic
905        /// #![feature(strict_overflow_ops)]
906        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_mul(2);")]
907        /// ```
908        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
909        #[must_use = "this returns the result of the operation, \
910                      without modifying the original"]
911        #[inline]
912        #[track_caller]
913        pub const fn strict_mul(self, rhs: Self) -> Self {
914            let (a, b) = self.overflowing_mul(rhs);
915            if b { overflow_panic::mul() } else { a }
916         }
917
918        /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow
919        /// cannot occur.
920        ///
921        /// Calling `x.unchecked_mul(y)` is semantically equivalent to calling
922        /// `x.`[`checked_mul`]`(y).`[`unwrap_unchecked`]`()`.
923        ///
924        /// If you're just trying to avoid the panic in debug mode, then **do not**
925        /// use this.  Instead, you're looking for [`wrapping_mul`].
926        ///
927        /// # Safety
928        ///
929        /// This results in undefined behavior when
930        #[doc = concat!("`self * rhs > ", stringify!($SelfT), "::MAX` or `self * rhs < ", stringify!($SelfT), "::MIN`,")]
931        /// i.e. when [`checked_mul`] would return `None`.
932        ///
933        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
934        #[doc = concat!("[`checked_mul`]: ", stringify!($SelfT), "::checked_mul")]
935        #[doc = concat!("[`wrapping_mul`]: ", stringify!($SelfT), "::wrapping_mul")]
936        #[stable(feature = "unchecked_math", since = "1.79.0")]
937        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
938        #[must_use = "this returns the result of the operation, \
939                      without modifying the original"]
940        #[inline(always)]
941        #[track_caller]
942        pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
943            assert_unsafe_precondition!(
944                check_language_ub,
945                concat!(stringify!($SelfT), "::unchecked_mul cannot overflow"),
946                (
947                    lhs: $SelfT = self,
948                    rhs: $SelfT = rhs,
949                ) => !lhs.overflowing_mul(rhs).1,
950            );
951
952            // SAFETY: this is guaranteed to be safe by the caller.
953            unsafe {
954                intrinsics::unchecked_mul(self, rhs)
955            }
956        }
957
958        /// Checked integer division. Computes `self / rhs`, returning `None`
959        /// if `rhs == 0`.
960        ///
961        /// # Examples
962        ///
963        /// ```
964        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".checked_div(2), Some(64));")]
965        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_div(0), None);")]
966        /// ```
967        #[stable(feature = "rust1", since = "1.0.0")]
968        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
969        #[must_use = "this returns the result of the operation, \
970                      without modifying the original"]
971        #[inline]
972        pub const fn checked_div(self, rhs: Self) -> Option<Self> {
973            if intrinsics::unlikely(rhs == 0) {
974                None
975            } else {
976                // SAFETY: div by zero has been checked above and unsigned types have no other
977                // failure modes for division
978                Some(unsafe { intrinsics::unchecked_div(self, rhs) })
979            }
980        }
981
982        /// Strict integer division. Computes `self / rhs`.
983        ///
984        /// Strict division on unsigned types is just normal division. There's no
985        /// way overflow could ever happen. This function exists so that all
986        /// operations are accounted for in the strict operations.
987        ///
988        /// # Panics
989        ///
990        /// This function will panic if `rhs` is zero.
991        ///
992        /// # Examples
993        ///
994        /// ```
995        /// #![feature(strict_overflow_ops)]
996        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_div(10), 10);")]
997        /// ```
998        ///
999        /// The following panics because of division by zero:
1000        ///
1001        /// ```should_panic
1002        /// #![feature(strict_overflow_ops)]
1003        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div(0);")]
1004        /// ```
1005        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1006        #[must_use = "this returns the result of the operation, \
1007                      without modifying the original"]
1008        #[inline(always)]
1009        #[track_caller]
1010        pub const fn strict_div(self, rhs: Self) -> Self {
1011            self / rhs
1012        }
1013
1014        /// Checked Euclidean division. Computes `self.div_euclid(rhs)`, returning `None`
1015        /// if `rhs == 0`.
1016        ///
1017        /// # Examples
1018        ///
1019        /// ```
1020        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".checked_div_euclid(2), Some(64));")]
1021        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_div_euclid(0), None);")]
1022        /// ```
1023        #[stable(feature = "euclidean_division", since = "1.38.0")]
1024        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1025        #[must_use = "this returns the result of the operation, \
1026                      without modifying the original"]
1027        #[inline]
1028        pub const fn checked_div_euclid(self, rhs: Self) -> Option<Self> {
1029            if intrinsics::unlikely(rhs == 0) {
1030                None
1031            } else {
1032                Some(self.div_euclid(rhs))
1033            }
1034        }
1035
1036        /// Strict Euclidean division. Computes `self.div_euclid(rhs)`.
1037        ///
1038        /// Strict division on unsigned types is just normal division. There's no
1039        /// way overflow could ever happen. This function exists so that all
1040        /// operations are accounted for in the strict operations. Since, for the
1041        /// positive integers, all common definitions of division are equal, this
1042        /// is exactly equal to `self.strict_div(rhs)`.
1043        ///
1044        /// # Panics
1045        ///
1046        /// This function will panic if `rhs` is zero.
1047        ///
1048        /// # Examples
1049        ///
1050        /// ```
1051        /// #![feature(strict_overflow_ops)]
1052        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_div_euclid(10), 10);")]
1053        /// ```
1054        /// The following panics because of division by zero:
1055        ///
1056        /// ```should_panic
1057        /// #![feature(strict_overflow_ops)]
1058        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div_euclid(0);")]
1059        /// ```
1060        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1061        #[must_use = "this returns the result of the operation, \
1062                      without modifying the original"]
1063        #[inline(always)]
1064        #[track_caller]
1065        pub const fn strict_div_euclid(self, rhs: Self) -> Self {
1066            self / rhs
1067        }
1068
1069        /// Checked integer division without remainder. Computes `self / rhs`.
1070        ///
1071        /// # Panics
1072        ///
1073        /// This function will panic  if `rhs == 0` or `self % rhs != 0`.
1074        ///
1075        /// # Examples
1076        ///
1077        /// ```
1078        /// #![feature(exact_div)]
1079        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(2), 32);")]
1080        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(32), 2);")]
1081        /// ```
1082        ///
1083        /// ```should_panic
1084        /// #![feature(exact_div)]
1085        #[doc = concat!("let _ = 65", stringify!($SelfT), ".exact_div(2);")]
1086        /// ```
1087        #[unstable(
1088            feature = "exact_div",
1089            issue = "139911",
1090        )]
1091        #[must_use = "this returns the result of the operation, \
1092                      without modifying the original"]
1093        #[inline]
1094        pub const fn checked_exact_div(self, rhs: Self) -> Option<Self> {
1095            if intrinsics::unlikely(rhs == 0) {
1096                None
1097            } else {
1098                // SAFETY: division by zero is checked above
1099                unsafe {
1100                    if intrinsics::unlikely(intrinsics::unchecked_rem(self, rhs) != 0) {
1101                        None
1102                    } else {
1103                        Some(intrinsics::exact_div(self, rhs))
1104                    }
1105                }
1106            }
1107        }
1108
1109        /// Checked integer division without remainder. Computes `self / rhs`.
1110        ///
1111        /// # Panics
1112        ///
1113        /// This function will panic  if `rhs == 0` or `self % rhs != 0`.
1114        ///
1115        /// # Examples
1116        ///
1117        /// ```
1118        /// #![feature(exact_div)]
1119        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(2), 32);")]
1120        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(32), 2);")]
1121        /// ```
1122        ///
1123        /// ```should_panic
1124        /// #![feature(exact_div)]
1125        #[doc = concat!("let _ = 65", stringify!($SelfT), ".exact_div(2);")]
1126        /// ```
1127        #[unstable(
1128            feature = "exact_div",
1129            issue = "139911",
1130        )]
1131        #[must_use = "this returns the result of the operation, \
1132                      without modifying the original"]
1133        #[inline]
1134        pub const fn exact_div(self, rhs: Self) -> Self {
1135            match self.checked_exact_div(rhs) {
1136                Some(x) => x,
1137                None => panic!("Failed to divide without remainder"),
1138            }
1139        }
1140
1141        /// Unchecked integer division without remainder. Computes `self / rhs`.
1142        ///
1143        /// # Safety
1144        ///
1145        /// This results in undefined behavior when `rhs == 0` or `self % rhs != 0`,
1146        /// i.e. when [`checked_exact_div`](Self::checked_exact_div) would return `None`.
1147        #[unstable(
1148            feature = "exact_div",
1149            issue = "139911",
1150        )]
1151        #[must_use = "this returns the result of the operation, \
1152                      without modifying the original"]
1153        #[inline]
1154        pub const unsafe fn unchecked_exact_div(self, rhs: Self) -> Self {
1155            assert_unsafe_precondition!(
1156                check_language_ub,
1157                concat!(stringify!($SelfT), "::unchecked_exact_div divide by zero or leave a remainder"),
1158                (
1159                    lhs: $SelfT = self,
1160                    rhs: $SelfT = rhs,
1161                ) => rhs > 0 && lhs % rhs == 0,
1162            );
1163            // SAFETY: Same precondition
1164            unsafe { intrinsics::exact_div(self, rhs) }
1165        }
1166
1167        /// Checked integer remainder. Computes `self % rhs`, returning `None`
1168        /// if `rhs == 0`.
1169        ///
1170        /// # Examples
1171        ///
1172        /// ```
1173        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(2), Some(1));")]
1174        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(0), None);")]
1175        /// ```
1176        #[stable(feature = "wrapping", since = "1.7.0")]
1177        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
1178        #[must_use = "this returns the result of the operation, \
1179                      without modifying the original"]
1180        #[inline]
1181        pub const fn checked_rem(self, rhs: Self) -> Option<Self> {
1182            if intrinsics::unlikely(rhs == 0) {
1183                None
1184            } else {
1185                // SAFETY: div by zero has been checked above and unsigned types have no other
1186                // failure modes for division
1187                Some(unsafe { intrinsics::unchecked_rem(self, rhs) })
1188            }
1189        }
1190
1191        /// Strict integer remainder. Computes `self % rhs`.
1192        ///
1193        /// Strict remainder calculation on unsigned types is just the regular
1194        /// remainder calculation. There's no way overflow could ever happen.
1195        /// This function exists so that all operations are accounted for in the
1196        /// strict operations.
1197        ///
1198        /// # Panics
1199        ///
1200        /// This function will panic if `rhs` is zero.
1201        ///
1202        /// # Examples
1203        ///
1204        /// ```
1205        /// #![feature(strict_overflow_ops)]
1206        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_rem(10), 0);")]
1207        /// ```
1208        ///
1209        /// The following panics because of division by zero:
1210        ///
1211        /// ```should_panic
1212        /// #![feature(strict_overflow_ops)]
1213        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem(0);")]
1214        /// ```
1215        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1216        #[must_use = "this returns the result of the operation, \
1217                      without modifying the original"]
1218        #[inline(always)]
1219        #[track_caller]
1220        pub const fn strict_rem(self, rhs: Self) -> Self {
1221            self % rhs
1222        }
1223
1224        /// Checked Euclidean modulo. Computes `self.rem_euclid(rhs)`, returning `None`
1225        /// if `rhs == 0`.
1226        ///
1227        /// # Examples
1228        ///
1229        /// ```
1230        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(2), Some(1));")]
1231        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(0), None);")]
1232        /// ```
1233        #[stable(feature = "euclidean_division", since = "1.38.0")]
1234        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1235        #[must_use = "this returns the result of the operation, \
1236                      without modifying the original"]
1237        #[inline]
1238        pub const fn checked_rem_euclid(self, rhs: Self) -> Option<Self> {
1239            if intrinsics::unlikely(rhs == 0) {
1240                None
1241            } else {
1242                Some(self.rem_euclid(rhs))
1243            }
1244        }
1245
1246        /// Strict Euclidean modulo. Computes `self.rem_euclid(rhs)`.
1247        ///
1248        /// Strict modulo calculation on unsigned types is just the regular
1249        /// remainder calculation. There's no way overflow could ever happen.
1250        /// This function exists so that all operations are accounted for in the
1251        /// strict operations. Since, for the positive integers, all common
1252        /// definitions of division are equal, this is exactly equal to
1253        /// `self.strict_rem(rhs)`.
1254        ///
1255        /// # Panics
1256        ///
1257        /// This function will panic if `rhs` is zero.
1258        ///
1259        /// # Examples
1260        ///
1261        /// ```
1262        /// #![feature(strict_overflow_ops)]
1263        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_rem_euclid(10), 0);")]
1264        /// ```
1265        ///
1266        /// The following panics because of division by zero:
1267        ///
1268        /// ```should_panic
1269        /// #![feature(strict_overflow_ops)]
1270        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem_euclid(0);")]
1271        /// ```
1272        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1273        #[must_use = "this returns the result of the operation, \
1274                      without modifying the original"]
1275        #[inline(always)]
1276        #[track_caller]
1277        pub const fn strict_rem_euclid(self, rhs: Self) -> Self {
1278            self % rhs
1279        }
1280
1281        /// Same value as `self | other`, but UB if any bit position is set in both inputs.
1282        ///
1283        /// This is a situational micro-optimization for places where you'd rather
1284        /// use addition on some platforms and bitwise or on other platforms, based
1285        /// on exactly which instructions combine better with whatever else you're
1286        /// doing.  Note that there's no reason to bother using this for places
1287        /// where it's clear from the operations involved that they can't overlap.
1288        /// For example, if you're combining `u16`s into a `u32` with
1289        /// `((a as u32) << 16) | (b as u32)`, that's fine, as the backend will
1290        /// know those sides of the `|` are disjoint without needing help.
1291        ///
1292        /// # Examples
1293        ///
1294        /// ```
1295        /// #![feature(disjoint_bitor)]
1296        ///
1297        /// // SAFETY: `1` and `4` have no bits in common.
1298        /// unsafe {
1299        #[doc = concat!("    assert_eq!(1_", stringify!($SelfT), ".unchecked_disjoint_bitor(4), 5);")]
1300        /// }
1301        /// ```
1302        ///
1303        /// # Safety
1304        ///
1305        /// Requires that `(self & other) == 0`, otherwise it's immediate UB.
1306        ///
1307        /// Equivalently, requires that `(self | other) == (self + other)`.
1308        #[unstable(feature = "disjoint_bitor", issue = "135758")]
1309        #[rustc_const_unstable(feature = "disjoint_bitor", issue = "135758")]
1310        #[inline]
1311        pub const unsafe fn unchecked_disjoint_bitor(self, other: Self) -> Self {
1312            assert_unsafe_precondition!(
1313                check_language_ub,
1314                concat!(stringify!($SelfT), "::unchecked_disjoint_bitor cannot have overlapping bits"),
1315                (
1316                    lhs: $SelfT = self,
1317                    rhs: $SelfT = other,
1318                ) => (lhs & rhs) == 0,
1319            );
1320
1321            // SAFETY: Same precondition
1322            unsafe { intrinsics::disjoint_bitor(self, other) }
1323        }
1324
1325        /// Returns the logarithm of the number with respect to an arbitrary base,
1326        /// rounded down.
1327        ///
1328        /// This method might not be optimized owing to implementation details;
1329        /// `ilog2` can produce results more efficiently for base 2, and `ilog10`
1330        /// can produce results more efficiently for base 10.
1331        ///
1332        /// # Panics
1333        ///
1334        /// This function will panic if `self` is zero, or if `base` is less than 2.
1335        ///
1336        /// # Examples
1337        ///
1338        /// ```
1339        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")]
1340        /// ```
1341        #[stable(feature = "int_log", since = "1.67.0")]
1342        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1343        #[must_use = "this returns the result of the operation, \
1344                      without modifying the original"]
1345        #[inline]
1346        #[track_caller]
1347        pub const fn ilog(self, base: Self) -> u32 {
1348            assert!(base >= 2, "base of integer logarithm must be at least 2");
1349            if let Some(log) = self.checked_ilog(base) {
1350                log
1351            } else {
1352                int_log10::panic_for_nonpositive_argument()
1353            }
1354        }
1355
1356        /// Returns the base 2 logarithm of the number, rounded down.
1357        ///
1358        /// # Panics
1359        ///
1360        /// This function will panic if `self` is zero.
1361        ///
1362        /// # Examples
1363        ///
1364        /// ```
1365        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")]
1366        /// ```
1367        #[stable(feature = "int_log", since = "1.67.0")]
1368        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1369        #[must_use = "this returns the result of the operation, \
1370                      without modifying the original"]
1371        #[inline]
1372        #[track_caller]
1373        pub const fn ilog2(self) -> u32 {
1374            if let Some(log) = self.checked_ilog2() {
1375                log
1376            } else {
1377                int_log10::panic_for_nonpositive_argument()
1378            }
1379        }
1380
1381        /// Returns the base 10 logarithm of the number, rounded down.
1382        ///
1383        /// # Panics
1384        ///
1385        /// This function will panic if `self` is zero.
1386        ///
1387        /// # Example
1388        ///
1389        /// ```
1390        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")]
1391        /// ```
1392        #[stable(feature = "int_log", since = "1.67.0")]
1393        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1394        #[must_use = "this returns the result of the operation, \
1395                      without modifying the original"]
1396        #[inline]
1397        #[track_caller]
1398        pub const fn ilog10(self) -> u32 {
1399            if let Some(log) = self.checked_ilog10() {
1400                log
1401            } else {
1402                int_log10::panic_for_nonpositive_argument()
1403            }
1404        }
1405
1406        /// Returns the logarithm of the number with respect to an arbitrary base,
1407        /// rounded down.
1408        ///
1409        /// Returns `None` if the number is zero, or if the base is not at least 2.
1410        ///
1411        /// This method might not be optimized owing to implementation details;
1412        /// `checked_ilog2` can produce results more efficiently for base 2, and
1413        /// `checked_ilog10` can produce results more efficiently for base 10.
1414        ///
1415        /// # Examples
1416        ///
1417        /// ```
1418        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")]
1419        /// ```
1420        #[stable(feature = "int_log", since = "1.67.0")]
1421        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1422        #[must_use = "this returns the result of the operation, \
1423                      without modifying the original"]
1424        #[inline]
1425        pub const fn checked_ilog(self, base: Self) -> Option<u32> {
1426            if self <= 0 || base <= 1 {
1427                None
1428            } else if self < base {
1429                Some(0)
1430            } else {
1431                // Since base >= self, n >= 1
1432                let mut n = 1;
1433                let mut r = base;
1434
1435                // Optimization for 128 bit wide integers.
1436                if Self::BITS == 128 {
1437                    // The following is a correct lower bound for ⌊log(base,self)⌋ because
1438                    //
1439                    // log(base,self) = log(2,self) / log(2,base)
1440                    //                ≥ ⌊log(2,self)⌋ / (⌊log(2,base)⌋ + 1)
1441                    //
1442                    // hence
1443                    //
1444                    // ⌊log(base,self)⌋ ≥ ⌊ ⌊log(2,self)⌋ / (⌊log(2,base)⌋ + 1) ⌋ .
1445                    n = self.ilog2() / (base.ilog2() + 1);
1446                    r = base.pow(n);
1447                }
1448
1449                while r <= self / base {
1450                    n += 1;
1451                    r *= base;
1452                }
1453                Some(n)
1454            }
1455        }
1456
1457        /// Returns the base 2 logarithm of the number, rounded down.
1458        ///
1459        /// Returns `None` if the number is zero.
1460        ///
1461        /// # Examples
1462        ///
1463        /// ```
1464        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")]
1465        /// ```
1466        #[stable(feature = "int_log", since = "1.67.0")]
1467        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1468        #[must_use = "this returns the result of the operation, \
1469                      without modifying the original"]
1470        #[inline]
1471        pub const fn checked_ilog2(self) -> Option<u32> {
1472            match NonZero::new(self) {
1473                Some(x) => Some(x.ilog2()),
1474                None => None,
1475            }
1476        }
1477
1478        /// Returns the base 10 logarithm of the number, rounded down.
1479        ///
1480        /// Returns `None` if the number is zero.
1481        ///
1482        /// # Examples
1483        ///
1484        /// ```
1485        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")]
1486        /// ```
1487        #[stable(feature = "int_log", since = "1.67.0")]
1488        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1489        #[must_use = "this returns the result of the operation, \
1490                      without modifying the original"]
1491        #[inline]
1492        pub const fn checked_ilog10(self) -> Option<u32> {
1493            match NonZero::new(self) {
1494                Some(x) => Some(x.ilog10()),
1495                None => None,
1496            }
1497        }
1498
1499        /// Checked negation. Computes `-self`, returning `None` unless `self ==
1500        /// 0`.
1501        ///
1502        /// Note that negating any positive integer will overflow.
1503        ///
1504        /// # Examples
1505        ///
1506        /// ```
1507        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".checked_neg(), Some(0));")]
1508        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_neg(), None);")]
1509        /// ```
1510        #[stable(feature = "wrapping", since = "1.7.0")]
1511        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1512        #[must_use = "this returns the result of the operation, \
1513                      without modifying the original"]
1514        #[inline]
1515        pub const fn checked_neg(self) -> Option<Self> {
1516            let (a, b) = self.overflowing_neg();
1517            if intrinsics::unlikely(b) { None } else { Some(a) }
1518        }
1519
1520        /// Strict negation. Computes `-self`, panicking unless `self ==
1521        /// 0`.
1522        ///
1523        /// Note that negating any positive integer will overflow.
1524        ///
1525        /// # Panics
1526        ///
1527        /// ## Overflow behavior
1528        ///
1529        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1530        ///
1531        /// # Examples
1532        ///
1533        /// ```
1534        /// #![feature(strict_overflow_ops)]
1535        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".strict_neg(), 0);")]
1536        /// ```
1537        ///
1538        /// The following panics because of overflow:
1539        ///
1540        /// ```should_panic
1541        /// #![feature(strict_overflow_ops)]
1542        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_neg();")]
1543        ///
1544        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1545        #[must_use = "this returns the result of the operation, \
1546                      without modifying the original"]
1547        #[inline]
1548        #[track_caller]
1549        pub const fn strict_neg(self) -> Self {
1550            let (a, b) = self.overflowing_neg();
1551            if b { overflow_panic::neg() } else { a }
1552        }
1553
1554        /// Checked shift left. Computes `self << rhs`, returning `None`
1555        /// if `rhs` is larger than or equal to the number of bits in `self`.
1556        ///
1557        /// # Examples
1558        ///
1559        /// ```
1560        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(4), Some(0x10));")]
1561        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(129), None);")]
1562        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(", stringify!($BITS_MINUS_ONE), "), Some(0));")]
1563        /// ```
1564        #[stable(feature = "wrapping", since = "1.7.0")]
1565        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1566        #[must_use = "this returns the result of the operation, \
1567                      without modifying the original"]
1568        #[inline]
1569        pub const fn checked_shl(self, rhs: u32) -> Option<Self> {
1570            // Not using overflowing_shl as that's a wrapping shift
1571            if rhs < Self::BITS {
1572                // SAFETY: just checked the RHS is in-range
1573                Some(unsafe { self.unchecked_shl(rhs) })
1574            } else {
1575                None
1576            }
1577        }
1578
1579        /// Strict shift left. Computes `self << rhs`, panicking if `rhs` is larger
1580        /// than or equal to the number of bits in `self`.
1581        ///
1582        /// # Panics
1583        ///
1584        /// ## Overflow behavior
1585        ///
1586        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1587        ///
1588        /// # Examples
1589        ///
1590        /// ```
1591        /// #![feature(strict_overflow_ops)]
1592        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".strict_shl(4), 0x10);")]
1593        /// ```
1594        ///
1595        /// The following panics because of overflow:
1596        ///
1597        /// ```should_panic
1598        /// #![feature(strict_overflow_ops)]
1599        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shl(129);")]
1600        /// ```
1601        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1602        #[must_use = "this returns the result of the operation, \
1603                      without modifying the original"]
1604        #[inline]
1605        #[track_caller]
1606        pub const fn strict_shl(self, rhs: u32) -> Self {
1607            let (a, b) = self.overflowing_shl(rhs);
1608            if b { overflow_panic::shl() } else { a }
1609        }
1610
1611        /// Unchecked shift left. Computes `self << rhs`, assuming that
1612        /// `rhs` is less than the number of bits in `self`.
1613        ///
1614        /// # Safety
1615        ///
1616        /// This results in undefined behavior if `rhs` is larger than
1617        /// or equal to the number of bits in `self`,
1618        /// i.e. when [`checked_shl`] would return `None`.
1619        ///
1620        #[doc = concat!("[`checked_shl`]: ", stringify!($SelfT), "::checked_shl")]
1621        #[unstable(
1622            feature = "unchecked_shifts",
1623            reason = "niche optimization path",
1624            issue = "85122",
1625        )]
1626        #[must_use = "this returns the result of the operation, \
1627                      without modifying the original"]
1628        #[inline(always)]
1629        #[track_caller]
1630        pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
1631            assert_unsafe_precondition!(
1632                check_language_ub,
1633                concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"),
1634                (
1635                    rhs: u32 = rhs,
1636                ) => rhs < <$ActualT>::BITS,
1637            );
1638
1639            // SAFETY: this is guaranteed to be safe by the caller.
1640            unsafe {
1641                intrinsics::unchecked_shl(self, rhs)
1642            }
1643        }
1644
1645        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`.
1646        ///
1647        /// If `rhs` is larger or equal to the number of bits in `self`,
1648        /// the entire value is shifted out, and `0` is returned.
1649        ///
1650        /// # Examples
1651        ///
1652        /// ```
1653        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(4), 0x10);")]
1654        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(129), 0);")]
1655        /// ```
1656        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1657        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1658        #[must_use = "this returns the result of the operation, \
1659                      without modifying the original"]
1660        #[inline]
1661        pub const fn unbounded_shl(self, rhs: u32) -> $SelfT{
1662            if rhs < Self::BITS {
1663                // SAFETY:
1664                // rhs is just checked to be in-range above
1665                unsafe { self.unchecked_shl(rhs) }
1666            } else {
1667                0
1668            }
1669        }
1670
1671        /// Checked shift right. Computes `self >> rhs`, returning `None`
1672        /// if `rhs` is larger than or equal to the number of bits in `self`.
1673        ///
1674        /// # Examples
1675        ///
1676        /// ```
1677        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(4), Some(0x1));")]
1678        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(129), None);")]
1679        /// ```
1680        #[stable(feature = "wrapping", since = "1.7.0")]
1681        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1682        #[must_use = "this returns the result of the operation, \
1683                      without modifying the original"]
1684        #[inline]
1685        pub const fn checked_shr(self, rhs: u32) -> Option<Self> {
1686            // Not using overflowing_shr as that's a wrapping shift
1687            if rhs < Self::BITS {
1688                // SAFETY: just checked the RHS is in-range
1689                Some(unsafe { self.unchecked_shr(rhs) })
1690            } else {
1691                None
1692            }
1693        }
1694
1695        /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is
1696        /// larger than or equal to the number of bits in `self`.
1697        ///
1698        /// # Panics
1699        ///
1700        /// ## Overflow behavior
1701        ///
1702        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1703        ///
1704        /// # Examples
1705        ///
1706        /// ```
1707        /// #![feature(strict_overflow_ops)]
1708        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".strict_shr(4), 0x1);")]
1709        /// ```
1710        ///
1711        /// The following panics because of overflow:
1712        ///
1713        /// ```should_panic
1714        /// #![feature(strict_overflow_ops)]
1715        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shr(129);")]
1716        /// ```
1717        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1718        #[must_use = "this returns the result of the operation, \
1719                      without modifying the original"]
1720        #[inline]
1721        #[track_caller]
1722        pub const fn strict_shr(self, rhs: u32) -> Self {
1723            let (a, b) = self.overflowing_shr(rhs);
1724            if b { overflow_panic::shr() } else { a }
1725        }
1726
1727        /// Unchecked shift right. Computes `self >> rhs`, assuming that
1728        /// `rhs` is less than the number of bits in `self`.
1729        ///
1730        /// # Safety
1731        ///
1732        /// This results in undefined behavior if `rhs` is larger than
1733        /// or equal to the number of bits in `self`,
1734        /// i.e. when [`checked_shr`] would return `None`.
1735        ///
1736        #[doc = concat!("[`checked_shr`]: ", stringify!($SelfT), "::checked_shr")]
1737        #[unstable(
1738            feature = "unchecked_shifts",
1739            reason = "niche optimization path",
1740            issue = "85122",
1741        )]
1742        #[must_use = "this returns the result of the operation, \
1743                      without modifying the original"]
1744        #[inline(always)]
1745        #[track_caller]
1746        pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
1747            assert_unsafe_precondition!(
1748                check_language_ub,
1749                concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"),
1750                (
1751                    rhs: u32 = rhs,
1752                ) => rhs < <$ActualT>::BITS,
1753            );
1754
1755            // SAFETY: this is guaranteed to be safe by the caller.
1756            unsafe {
1757                intrinsics::unchecked_shr(self, rhs)
1758            }
1759        }
1760
1761        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`.
1762        ///
1763        /// If `rhs` is larger or equal to the number of bits in `self`,
1764        /// the entire value is shifted out, and `0` is returned.
1765        ///
1766        /// # Examples
1767        ///
1768        /// ```
1769        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(4), 0x1);")]
1770        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(129), 0);")]
1771        /// ```
1772        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1773        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1774        #[must_use = "this returns the result of the operation, \
1775                      without modifying the original"]
1776        #[inline]
1777        pub const fn unbounded_shr(self, rhs: u32) -> $SelfT{
1778            if rhs < Self::BITS {
1779                // SAFETY:
1780                // rhs is just checked to be in-range above
1781                unsafe { self.unchecked_shr(rhs) }
1782            } else {
1783                0
1784            }
1785        }
1786
1787        /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if
1788        /// overflow occurred.
1789        ///
1790        /// # Examples
1791        ///
1792        /// ```
1793        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_pow(5), Some(32));")]
1794        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_pow(2), None);")]
1795        /// ```
1796        #[stable(feature = "no_panic_pow", since = "1.34.0")]
1797        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
1798        #[must_use = "this returns the result of the operation, \
1799                      without modifying the original"]
1800        #[inline]
1801        pub const fn checked_pow(self, mut exp: u32) -> Option<Self> {
1802            if exp == 0 {
1803                return Some(1);
1804            }
1805            let mut base = self;
1806            let mut acc: Self = 1;
1807
1808            loop {
1809                if (exp & 1) == 1 {
1810                    acc = try_opt!(acc.checked_mul(base));
1811                    // since exp!=0, finally the exp must be 1.
1812                    if exp == 1 {
1813                        return Some(acc);
1814                    }
1815                }
1816                exp /= 2;
1817                base = try_opt!(base.checked_mul(base));
1818            }
1819        }
1820
1821        /// Strict exponentiation. Computes `self.pow(exp)`, panicking if
1822        /// overflow occurred.
1823        ///
1824        /// # Panics
1825        ///
1826        /// ## Overflow behavior
1827        ///
1828        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1829        ///
1830        /// # Examples
1831        ///
1832        /// ```
1833        /// #![feature(strict_overflow_ops)]
1834        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".strict_pow(5), 32);")]
1835        /// ```
1836        ///
1837        /// The following panics because of overflow:
1838        ///
1839        /// ```should_panic
1840        /// #![feature(strict_overflow_ops)]
1841        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_pow(2);")]
1842        /// ```
1843        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1844        #[must_use = "this returns the result of the operation, \
1845                      without modifying the original"]
1846        #[inline]
1847        #[track_caller]
1848        pub const fn strict_pow(self, mut exp: u32) -> Self {
1849            if exp == 0 {
1850                return 1;
1851            }
1852            let mut base = self;
1853            let mut acc: Self = 1;
1854
1855            loop {
1856                if (exp & 1) == 1 {
1857                    acc = acc.strict_mul(base);
1858                    // since exp!=0, finally the exp must be 1.
1859                    if exp == 1 {
1860                        return acc;
1861                    }
1862                }
1863                exp /= 2;
1864                base = base.strict_mul(base);
1865            }
1866        }
1867
1868        /// Saturating integer addition. Computes `self + rhs`, saturating at
1869        /// the numeric bounds instead of overflowing.
1870        ///
1871        /// # Examples
1872        ///
1873        /// ```
1874        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_add(1), 101);")]
1875        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add(127), ", stringify!($SelfT), "::MAX);")]
1876        /// ```
1877        #[stable(feature = "rust1", since = "1.0.0")]
1878        #[must_use = "this returns the result of the operation, \
1879                      without modifying the original"]
1880        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1881        #[inline(always)]
1882        pub const fn saturating_add(self, rhs: Self) -> Self {
1883            intrinsics::saturating_add(self, rhs)
1884        }
1885
1886        /// Saturating addition with a signed integer. Computes `self + rhs`,
1887        /// saturating at the numeric bounds instead of overflowing.
1888        ///
1889        /// # Examples
1890        ///
1891        /// ```
1892        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(2), 3);")]
1893        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(-2), 0);")]
1894        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_add_signed(4), ", stringify!($SelfT), "::MAX);")]
1895        /// ```
1896        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1897        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1898        #[must_use = "this returns the result of the operation, \
1899                      without modifying the original"]
1900        #[inline]
1901        pub const fn saturating_add_signed(self, rhs: $SignedT) -> Self {
1902            let (res, overflow) = self.overflowing_add(rhs as Self);
1903            if overflow == (rhs < 0) {
1904                res
1905            } else if overflow {
1906                Self::MAX
1907            } else {
1908                0
1909            }
1910        }
1911
1912        /// Saturating integer subtraction. Computes `self - rhs`, saturating
1913        /// at the numeric bounds instead of overflowing.
1914        ///
1915        /// # Examples
1916        ///
1917        /// ```
1918        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub(27), 73);")]
1919        #[doc = concat!("assert_eq!(13", stringify!($SelfT), ".saturating_sub(127), 0);")]
1920        /// ```
1921        #[stable(feature = "rust1", since = "1.0.0")]
1922        #[must_use = "this returns the result of the operation, \
1923                      without modifying the original"]
1924        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1925        #[inline(always)]
1926        pub const fn saturating_sub(self, rhs: Self) -> Self {
1927            intrinsics::saturating_sub(self, rhs)
1928        }
1929
1930        /// Saturating integer subtraction. Computes `self` - `rhs`, saturating at
1931        /// the numeric bounds instead of overflowing.
1932        ///
1933        /// # Examples
1934        ///
1935        /// ```
1936        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_sub_signed(2), 0);")]
1937        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_sub_signed(-2), 3);")]
1938        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_sub_signed(-4), ", stringify!($SelfT), "::MAX);")]
1939        /// ```
1940        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
1941        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
1942        #[must_use = "this returns the result of the operation, \
1943                      without modifying the original"]
1944        #[inline]
1945        pub const fn saturating_sub_signed(self, rhs: $SignedT) -> Self {
1946            let (res, overflow) = self.overflowing_sub_signed(rhs);
1947
1948            if !overflow {
1949                res
1950            } else if rhs < 0 {
1951                Self::MAX
1952            } else {
1953                0
1954            }
1955        }
1956
1957        /// Saturating integer multiplication. Computes `self * rhs`,
1958        /// saturating at the numeric bounds instead of overflowing.
1959        ///
1960        /// # Examples
1961        ///
1962        /// ```
1963        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".saturating_mul(10), 20);")]
1964        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).saturating_mul(10), ", stringify!($SelfT),"::MAX);")]
1965        /// ```
1966        #[stable(feature = "wrapping", since = "1.7.0")]
1967        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1968        #[must_use = "this returns the result of the operation, \
1969                      without modifying the original"]
1970        #[inline]
1971        pub const fn saturating_mul(self, rhs: Self) -> Self {
1972            match self.checked_mul(rhs) {
1973                Some(x) => x,
1974                None => Self::MAX,
1975            }
1976        }
1977
1978        /// Saturating integer division. Computes `self / rhs`, saturating at the
1979        /// numeric bounds instead of overflowing.
1980        ///
1981        /// # Panics
1982        ///
1983        /// This function will panic if `rhs` is zero.
1984        ///
1985        /// # Examples
1986        ///
1987        /// ```
1988        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".saturating_div(2), 2);")]
1989        ///
1990        /// ```
1991        #[stable(feature = "saturating_div", since = "1.58.0")]
1992        #[rustc_const_stable(feature = "saturating_div", since = "1.58.0")]
1993        #[must_use = "this returns the result of the operation, \
1994                      without modifying the original"]
1995        #[inline]
1996        #[track_caller]
1997        pub const fn saturating_div(self, rhs: Self) -> Self {
1998            // on unsigned types, there is no overflow in integer division
1999            self.wrapping_div(rhs)
2000        }
2001
2002        /// Saturating integer exponentiation. Computes `self.pow(exp)`,
2003        /// saturating at the numeric bounds instead of overflowing.
2004        ///
2005        /// # Examples
2006        ///
2007        /// ```
2008        #[doc = concat!("assert_eq!(4", stringify!($SelfT), ".saturating_pow(3), 64);")]
2009        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_pow(2), ", stringify!($SelfT), "::MAX);")]
2010        /// ```
2011        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2012        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2013        #[must_use = "this returns the result of the operation, \
2014                      without modifying the original"]
2015        #[inline]
2016        pub const fn saturating_pow(self, exp: u32) -> Self {
2017            match self.checked_pow(exp) {
2018                Some(x) => x,
2019                None => Self::MAX,
2020            }
2021        }
2022
2023        /// Wrapping (modular) addition. Computes `self + rhs`,
2024        /// wrapping around at the boundary of the type.
2025        ///
2026        /// # Examples
2027        ///
2028        /// ```
2029        #[doc = concat!("assert_eq!(200", stringify!($SelfT), ".wrapping_add(55), 255);")]
2030        #[doc = concat!("assert_eq!(200", stringify!($SelfT), ".wrapping_add(", stringify!($SelfT), "::MAX), 199);")]
2031        /// ```
2032        #[stable(feature = "rust1", since = "1.0.0")]
2033        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2034        #[must_use = "this returns the result of the operation, \
2035                      without modifying the original"]
2036        #[inline(always)]
2037        pub const fn wrapping_add(self, rhs: Self) -> Self {
2038            intrinsics::wrapping_add(self, rhs)
2039        }
2040
2041        /// Wrapping (modular) addition with a signed integer. Computes
2042        /// `self + rhs`, wrapping around at the boundary of the type.
2043        ///
2044        /// # Examples
2045        ///
2046        /// ```
2047        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(2), 3);")]
2048        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(-2), ", stringify!($SelfT), "::MAX);")]
2049        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_add_signed(4), 1);")]
2050        /// ```
2051        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2052        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2053        #[must_use = "this returns the result of the operation, \
2054                      without modifying the original"]
2055        #[inline]
2056        pub const fn wrapping_add_signed(self, rhs: $SignedT) -> Self {
2057            self.wrapping_add(rhs as Self)
2058        }
2059
2060        /// Wrapping (modular) subtraction. Computes `self - rhs`,
2061        /// wrapping around at the boundary of the type.
2062        ///
2063        /// # Examples
2064        ///
2065        /// ```
2066        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_sub(100), 0);")]
2067        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_sub(", stringify!($SelfT), "::MAX), 101);")]
2068        /// ```
2069        #[stable(feature = "rust1", since = "1.0.0")]
2070        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2071        #[must_use = "this returns the result of the operation, \
2072                      without modifying the original"]
2073        #[inline(always)]
2074        pub const fn wrapping_sub(self, rhs: Self) -> Self {
2075            intrinsics::wrapping_sub(self, rhs)
2076        }
2077
2078        /// Wrapping (modular) subtraction with a signed integer. Computes
2079        /// `self - rhs`, wrapping around at the boundary of the type.
2080        ///
2081        /// # Examples
2082        ///
2083        /// ```
2084        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_sub_signed(2), ", stringify!($SelfT), "::MAX);")]
2085        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_sub_signed(-2), 3);")]
2086        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_sub_signed(-4), 1);")]
2087        /// ```
2088        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2089        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2090        #[must_use = "this returns the result of the operation, \
2091                      without modifying the original"]
2092        #[inline]
2093        pub const fn wrapping_sub_signed(self, rhs: $SignedT) -> Self {
2094            self.wrapping_sub(rhs as Self)
2095        }
2096
2097        /// Wrapping (modular) multiplication. Computes `self *
2098        /// rhs`, wrapping around at the boundary of the type.
2099        ///
2100        /// # Examples
2101        ///
2102        /// Please note that this example is shared between integer types.
2103        /// Which explains why `u8` is used here.
2104        ///
2105        /// ```
2106        /// assert_eq!(10u8.wrapping_mul(12), 120);
2107        /// assert_eq!(25u8.wrapping_mul(12), 44);
2108        /// ```
2109        #[stable(feature = "rust1", since = "1.0.0")]
2110        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2111        #[must_use = "this returns the result of the operation, \
2112                      without modifying the original"]
2113        #[inline(always)]
2114        pub const fn wrapping_mul(self, rhs: Self) -> Self {
2115            intrinsics::wrapping_mul(self, rhs)
2116        }
2117
2118        /// Wrapping (modular) division. Computes `self / rhs`.
2119        ///
2120        /// Wrapped division on unsigned types is just normal division. There's
2121        /// no way wrapping could ever happen. This function exists so that all
2122        /// operations are accounted for in the wrapping operations.
2123        ///
2124        /// # Panics
2125        ///
2126        /// This function will panic if `rhs` is zero.
2127        ///
2128        /// # Examples
2129        ///
2130        /// ```
2131        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div(10), 10);")]
2132        /// ```
2133        #[stable(feature = "num_wrapping", since = "1.2.0")]
2134        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2135        #[must_use = "this returns the result of the operation, \
2136                      without modifying the original"]
2137        #[inline(always)]
2138        #[track_caller]
2139        pub const fn wrapping_div(self, rhs: Self) -> Self {
2140            self / rhs
2141        }
2142
2143        /// Wrapping Euclidean division. Computes `self.div_euclid(rhs)`.
2144        ///
2145        /// Wrapped division on unsigned types is just normal division. There's
2146        /// no way wrapping could ever happen. This function exists so that all
2147        /// operations are accounted for in the wrapping operations. Since, for
2148        /// the positive integers, all common definitions of division are equal,
2149        /// this is exactly equal to `self.wrapping_div(rhs)`.
2150        ///
2151        /// # Panics
2152        ///
2153        /// This function will panic if `rhs` is zero.
2154        ///
2155        /// # Examples
2156        ///
2157        /// ```
2158        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div_euclid(10), 10);")]
2159        /// ```
2160        #[stable(feature = "euclidean_division", since = "1.38.0")]
2161        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2162        #[must_use = "this returns the result of the operation, \
2163                      without modifying the original"]
2164        #[inline(always)]
2165        #[track_caller]
2166        pub const fn wrapping_div_euclid(self, rhs: Self) -> Self {
2167            self / rhs
2168        }
2169
2170        /// Wrapping (modular) remainder. Computes `self % rhs`.
2171        ///
2172        /// Wrapped remainder calculation on unsigned types is just the regular
2173        /// remainder calculation. There's no way wrapping could ever happen.
2174        /// This function exists so that all operations are accounted for in the
2175        /// wrapping operations.
2176        ///
2177        /// # Panics
2178        ///
2179        /// This function will panic if `rhs` is zero.
2180        ///
2181        /// # Examples
2182        ///
2183        /// ```
2184        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem(10), 0);")]
2185        /// ```
2186        #[stable(feature = "num_wrapping", since = "1.2.0")]
2187        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2188        #[must_use = "this returns the result of the operation, \
2189                      without modifying the original"]
2190        #[inline(always)]
2191        #[track_caller]
2192        pub const fn wrapping_rem(self, rhs: Self) -> Self {
2193            self % rhs
2194        }
2195
2196        /// Wrapping Euclidean modulo. Computes `self.rem_euclid(rhs)`.
2197        ///
2198        /// Wrapped modulo calculation on unsigned types is just the regular
2199        /// remainder calculation. There's no way wrapping could ever happen.
2200        /// This function exists so that all operations are accounted for in the
2201        /// wrapping operations. Since, for the positive integers, all common
2202        /// definitions of division are equal, this is exactly equal to
2203        /// `self.wrapping_rem(rhs)`.
2204        ///
2205        /// # Panics
2206        ///
2207        /// This function will panic if `rhs` is zero.
2208        ///
2209        /// # Examples
2210        ///
2211        /// ```
2212        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem_euclid(10), 0);")]
2213        /// ```
2214        #[stable(feature = "euclidean_division", since = "1.38.0")]
2215        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2216        #[must_use = "this returns the result of the operation, \
2217                      without modifying the original"]
2218        #[inline(always)]
2219        #[track_caller]
2220        pub const fn wrapping_rem_euclid(self, rhs: Self) -> Self {
2221            self % rhs
2222        }
2223
2224        /// Wrapping (modular) negation. Computes `-self`,
2225        /// wrapping around at the boundary of the type.
2226        ///
2227        /// Since unsigned types do not have negative equivalents
2228        /// all applications of this function will wrap (except for `-0`).
2229        /// For values smaller than the corresponding signed type's maximum
2230        /// the result is the same as casting the corresponding signed value.
2231        /// Any larger values are equivalent to `MAX + 1 - (val - MAX - 1)` where
2232        /// `MAX` is the corresponding signed type's maximum.
2233        ///
2234        /// # Examples
2235        ///
2236        /// ```
2237        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".wrapping_neg(), 0);")]
2238        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_neg(), 1);")]
2239        #[doc = concat!("assert_eq!(13_", stringify!($SelfT), ".wrapping_neg(), (!13) + 1);")]
2240        #[doc = concat!("assert_eq!(42_", stringify!($SelfT), ".wrapping_neg(), !(42 - 1));")]
2241        /// ```
2242        #[stable(feature = "num_wrapping", since = "1.2.0")]
2243        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2244        #[must_use = "this returns the result of the operation, \
2245                      without modifying the original"]
2246        #[inline(always)]
2247        pub const fn wrapping_neg(self) -> Self {
2248            (0 as $SelfT).wrapping_sub(self)
2249        }
2250
2251        /// Panic-free bitwise shift-left; yields `self << mask(rhs)`,
2252        /// where `mask` removes any high-order bits of `rhs` that
2253        /// would cause the shift to exceed the bitwidth of the type.
2254        ///
2255        /// Note that this is *not* the same as a rotate-left; the
2256        /// RHS of a wrapping shift-left is restricted to the range
2257        /// of the type, rather than the bits shifted out of the LHS
2258        /// being returned to the other end. The primitive integer
2259        /// types all implement a [`rotate_left`](Self::rotate_left) function,
2260        /// which may be what you want instead.
2261        ///
2262        /// # Examples
2263        ///
2264        /// ```
2265        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_shl(7), 128);")]
2266        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_shl(128), 1);")]
2267        /// ```
2268        #[stable(feature = "num_wrapping", since = "1.2.0")]
2269        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2270        #[must_use = "this returns the result of the operation, \
2271                      without modifying the original"]
2272        #[inline(always)]
2273        pub const fn wrapping_shl(self, rhs: u32) -> Self {
2274            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2275            // out of bounds
2276            unsafe {
2277                self.unchecked_shl(rhs & (Self::BITS - 1))
2278            }
2279        }
2280
2281        /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`,
2282        /// where `mask` removes any high-order bits of `rhs` that
2283        /// would cause the shift to exceed the bitwidth of the type.
2284        ///
2285        /// Note that this is *not* the same as a rotate-right; the
2286        /// RHS of a wrapping shift-right is restricted to the range
2287        /// of the type, rather than the bits shifted out of the LHS
2288        /// being returned to the other end. The primitive integer
2289        /// types all implement a [`rotate_right`](Self::rotate_right) function,
2290        /// which may be what you want instead.
2291        ///
2292        /// # Examples
2293        ///
2294        /// ```
2295        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".wrapping_shr(7), 1);")]
2296        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".wrapping_shr(128), 128);")]
2297        /// ```
2298        #[stable(feature = "num_wrapping", since = "1.2.0")]
2299        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2300        #[must_use = "this returns the result of the operation, \
2301                      without modifying the original"]
2302        #[inline(always)]
2303        pub const fn wrapping_shr(self, rhs: u32) -> Self {
2304            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2305            // out of bounds
2306            unsafe {
2307                self.unchecked_shr(rhs & (Self::BITS - 1))
2308            }
2309        }
2310
2311        /// Wrapping (modular) exponentiation. Computes `self.pow(exp)`,
2312        /// wrapping around at the boundary of the type.
2313        ///
2314        /// # Examples
2315        ///
2316        /// ```
2317        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_pow(5), 243);")]
2318        /// assert_eq!(3u8.wrapping_pow(6), 217);
2319        /// ```
2320        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2321        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2322        #[must_use = "this returns the result of the operation, \
2323                      without modifying the original"]
2324        #[inline]
2325        pub const fn wrapping_pow(self, mut exp: u32) -> Self {
2326            if exp == 0 {
2327                return 1;
2328            }
2329            let mut base = self;
2330            let mut acc: Self = 1;
2331
2332            if intrinsics::is_val_statically_known(exp) {
2333                while exp > 1 {
2334                    if (exp & 1) == 1 {
2335                        acc = acc.wrapping_mul(base);
2336                    }
2337                    exp /= 2;
2338                    base = base.wrapping_mul(base);
2339                }
2340
2341                // since exp!=0, finally the exp must be 1.
2342                // Deal with the final bit of the exponent separately, since
2343                // squaring the base afterwards is not necessary.
2344                acc.wrapping_mul(base)
2345            } else {
2346                // This is faster than the above when the exponent is not known
2347                // at compile time. We can't use the same code for the constant
2348                // exponent case because LLVM is currently unable to unroll
2349                // this loop.
2350                loop {
2351                    if (exp & 1) == 1 {
2352                        acc = acc.wrapping_mul(base);
2353                        // since exp!=0, finally the exp must be 1.
2354                        if exp == 1 {
2355                            return acc;
2356                        }
2357                    }
2358                    exp /= 2;
2359                    base = base.wrapping_mul(base);
2360                }
2361            }
2362        }
2363
2364        /// Calculates `self` + `rhs`.
2365        ///
2366        /// Returns a tuple of the addition along with a boolean indicating
2367        /// whether an arithmetic overflow would occur. If an overflow would
2368        /// have occurred then the wrapped value is returned.
2369        ///
2370        /// # Examples
2371        ///
2372        /// ```
2373        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_add(2), (7, false));")]
2374        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.overflowing_add(1), (0, true));")]
2375        /// ```
2376        #[stable(feature = "wrapping", since = "1.7.0")]
2377        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2378        #[must_use = "this returns the result of the operation, \
2379                      without modifying the original"]
2380        #[inline(always)]
2381        pub const fn overflowing_add(self, rhs: Self) -> (Self, bool) {
2382            let (a, b) = intrinsics::add_with_overflow(self as $ActualT, rhs as $ActualT);
2383            (a as Self, b)
2384        }
2385
2386        /// Calculates `self` + `rhs` + `carry` and returns a tuple containing
2387        /// the sum and the output carry.
2388        ///
2389        /// Performs "ternary addition" of two integer operands and a carry-in
2390        /// bit, and returns an output integer and a carry-out bit. This allows
2391        /// chaining together multiple additions to create a wider addition, and
2392        /// can be useful for bignum addition.
2393        ///
2394        #[doc = concat!("This can be thought of as a ", stringify!($BITS), "-bit \"full adder\", in the electronics sense.")]
2395        ///
2396        /// If the input carry is false, this method is equivalent to
2397        /// [`overflowing_add`](Self::overflowing_add), and the output carry is
2398        /// equal to the overflow flag. Note that although carry and overflow
2399        /// flags are similar for unsigned integers, they are different for
2400        /// signed integers.
2401        ///
2402        /// # Examples
2403        ///
2404        /// ```
2405        /// #![feature(bigint_helper_methods)]
2406        ///
2407        #[doc = concat!("//    3  MAX    (a = 3 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2408        #[doc = concat!("// +  5    7    (b = 5 × 2^", stringify!($BITS), " + 7)")]
2409        /// // ---------
2410        #[doc = concat!("//    9    6    (sum = 9 × 2^", stringify!($BITS), " + 6)")]
2411        ///
2412        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (3, ", stringify!($SelfT), "::MAX);")]
2413        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (5, 7);")]
2414        /// let carry0 = false;
2415        ///
2416        /// let (sum0, carry1) = a0.carrying_add(b0, carry0);
2417        /// assert_eq!(carry1, true);
2418        /// let (sum1, carry2) = a1.carrying_add(b1, carry1);
2419        /// assert_eq!(carry2, false);
2420        ///
2421        /// assert_eq!((sum1, sum0), (9, 6));
2422        /// ```
2423        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2424        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2425        #[must_use = "this returns the result of the operation, \
2426                      without modifying the original"]
2427        #[inline]
2428        pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) {
2429            // note: longer-term this should be done via an intrinsic, but this has been shown
2430            //   to generate optimal code for now, and LLVM doesn't have an equivalent intrinsic
2431            let (a, c1) = self.overflowing_add(rhs);
2432            let (b, c2) = a.overflowing_add(carry as $SelfT);
2433            // Ideally LLVM would know this is disjoint without us telling them,
2434            // but it doesn't <https://github.com/llvm/llvm-project/issues/118162>
2435            // SAFETY: Only one of `c1` and `c2` can be set.
2436            // For c1 to be set we need to have overflowed, but if we did then
2437            // `a` is at most `MAX-1`, which means that `c2` cannot possibly
2438            // overflow because it's adding at most `1` (since it came from `bool`)
2439            (b, unsafe { intrinsics::disjoint_bitor(c1, c2) })
2440        }
2441
2442        /// Calculates `self` + `rhs` with a signed `rhs`.
2443        ///
2444        /// Returns a tuple of the addition along with a boolean indicating
2445        /// whether an arithmetic overflow would occur. If an overflow would
2446        /// have occurred then the wrapped value is returned.
2447        ///
2448        /// # Examples
2449        ///
2450        /// ```
2451        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(2), (3, false));")]
2452        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(-2), (", stringify!($SelfT), "::MAX, true));")]
2453        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_signed(4), (1, true));")]
2454        /// ```
2455        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2456        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2457        #[must_use = "this returns the result of the operation, \
2458                      without modifying the original"]
2459        #[inline]
2460        pub const fn overflowing_add_signed(self, rhs: $SignedT) -> (Self, bool) {
2461            let (res, overflowed) = self.overflowing_add(rhs as Self);
2462            (res, overflowed ^ (rhs < 0))
2463        }
2464
2465        /// Calculates `self` - `rhs`.
2466        ///
2467        /// Returns a tuple of the subtraction along with a boolean indicating
2468        /// whether an arithmetic overflow would occur. If an overflow would
2469        /// have occurred then the wrapped value is returned.
2470        ///
2471        /// # Examples
2472        ///
2473        /// ```
2474        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_sub(2), (3, false));")]
2475        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_sub(1), (", stringify!($SelfT), "::MAX, true));")]
2476        /// ```
2477        #[stable(feature = "wrapping", since = "1.7.0")]
2478        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2479        #[must_use = "this returns the result of the operation, \
2480                      without modifying the original"]
2481        #[inline(always)]
2482        pub const fn overflowing_sub(self, rhs: Self) -> (Self, bool) {
2483            let (a, b) = intrinsics::sub_with_overflow(self as $ActualT, rhs as $ActualT);
2484            (a as Self, b)
2485        }
2486
2487        /// Calculates `self` &minus; `rhs` &minus; `borrow` and returns a tuple
2488        /// containing the difference and the output borrow.
2489        ///
2490        /// Performs "ternary subtraction" by subtracting both an integer
2491        /// operand and a borrow-in bit from `self`, and returns an output
2492        /// integer and a borrow-out bit. This allows chaining together multiple
2493        /// subtractions to create a wider subtraction, and can be useful for
2494        /// bignum subtraction.
2495        ///
2496        /// # Examples
2497        ///
2498        /// ```
2499        /// #![feature(bigint_helper_methods)]
2500        ///
2501        #[doc = concat!("//    9    6    (a = 9 × 2^", stringify!($BITS), " + 6)")]
2502        #[doc = concat!("// -  5    7    (b = 5 × 2^", stringify!($BITS), " + 7)")]
2503        /// // ---------
2504        #[doc = concat!("//    3  MAX    (diff = 3 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2505        ///
2506        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (9, 6);")]
2507        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (5, 7);")]
2508        /// let borrow0 = false;
2509        ///
2510        /// let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0);
2511        /// assert_eq!(borrow1, true);
2512        /// let (diff1, borrow2) = a1.borrowing_sub(b1, borrow1);
2513        /// assert_eq!(borrow2, false);
2514        ///
2515        #[doc = concat!("assert_eq!((diff1, diff0), (3, ", stringify!($SelfT), "::MAX));")]
2516        /// ```
2517        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2518        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2519        #[must_use = "this returns the result of the operation, \
2520                      without modifying the original"]
2521        #[inline]
2522        pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) {
2523            // note: longer-term this should be done via an intrinsic, but this has been shown
2524            //   to generate optimal code for now, and LLVM doesn't have an equivalent intrinsic
2525            let (a, c1) = self.overflowing_sub(rhs);
2526            let (b, c2) = a.overflowing_sub(borrow as $SelfT);
2527            // SAFETY: Only one of `c1` and `c2` can be set.
2528            // For c1 to be set we need to have underflowed, but if we did then
2529            // `a` is nonzero, which means that `c2` cannot possibly
2530            // underflow because it's subtracting at most `1` (since it came from `bool`)
2531            (b, unsafe { intrinsics::disjoint_bitor(c1, c2) })
2532        }
2533
2534        /// Calculates `self` - `rhs` with a signed `rhs`
2535        ///
2536        /// Returns a tuple of the subtraction along with a boolean indicating
2537        /// whether an arithmetic overflow would occur. If an overflow would
2538        /// have occurred then the wrapped value is returned.
2539        ///
2540        /// # Examples
2541        ///
2542        /// ```
2543        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_signed(2), (", stringify!($SelfT), "::MAX, true));")]
2544        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_signed(-2), (3, false));")]
2545        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_sub_signed(-4), (1, true));")]
2546        /// ```
2547        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2548        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2549        #[must_use = "this returns the result of the operation, \
2550                      without modifying the original"]
2551        #[inline]
2552        pub const fn overflowing_sub_signed(self, rhs: $SignedT) -> (Self, bool) {
2553            let (res, overflow) = self.overflowing_sub(rhs as Self);
2554
2555            (res, overflow ^ (rhs < 0))
2556        }
2557
2558        /// Computes the absolute difference between `self` and `other`.
2559        ///
2560        /// # Examples
2561        ///
2562        /// ```
2563        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(80), 20", stringify!($SelfT), ");")]
2564        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(110), 10", stringify!($SelfT), ");")]
2565        /// ```
2566        #[stable(feature = "int_abs_diff", since = "1.60.0")]
2567        #[rustc_const_stable(feature = "int_abs_diff", since = "1.60.0")]
2568        #[must_use = "this returns the result of the operation, \
2569                      without modifying the original"]
2570        #[inline]
2571        pub const fn abs_diff(self, other: Self) -> Self {
2572            if size_of::<Self>() == 1 {
2573                // Trick LLVM into generating the psadbw instruction when SSE2
2574                // is available and this function is autovectorized for u8's.
2575                (self as i32).wrapping_sub(other as i32).unsigned_abs() as Self
2576            } else {
2577                if self < other {
2578                    other - self
2579                } else {
2580                    self - other
2581                }
2582            }
2583        }
2584
2585        /// Calculates the multiplication of `self` and `rhs`.
2586        ///
2587        /// Returns a tuple of the multiplication along with a boolean
2588        /// indicating whether an arithmetic overflow would occur. If an
2589        /// overflow would have occurred then the wrapped value is returned.
2590        ///
2591        /// # Examples
2592        ///
2593        /// Please note that this example is shared between integer types.
2594        /// Which explains why `u32` is used here.
2595        ///
2596        /// ```
2597        /// assert_eq!(5u32.overflowing_mul(2), (10, false));
2598        /// assert_eq!(1_000_000_000u32.overflowing_mul(10), (1410065408, true));
2599        /// ```
2600        #[stable(feature = "wrapping", since = "1.7.0")]
2601        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2602        #[must_use = "this returns the result of the operation, \
2603                          without modifying the original"]
2604        #[inline(always)]
2605        pub const fn overflowing_mul(self, rhs: Self) -> (Self, bool) {
2606            let (a, b) = intrinsics::mul_with_overflow(self as $ActualT, rhs as $ActualT);
2607            (a as Self, b)
2608        }
2609
2610        /// Calculates the complete product `self * rhs` without the possibility to overflow.
2611        ///
2612        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2613        /// of the result as two separate values, in that order.
2614        ///
2615        /// If you also need to add a carry to the wide result, then you want
2616        /// [`Self::carrying_mul`] instead.
2617        ///
2618        /// # Examples
2619        ///
2620        /// Please note that this example is shared between integer types.
2621        /// Which explains why `u32` is used here.
2622        ///
2623        /// ```
2624        /// #![feature(bigint_helper_methods)]
2625        /// assert_eq!(5u32.widening_mul(2), (10, 0));
2626        /// assert_eq!(1_000_000_000u32.widening_mul(10), (1410065408, 2));
2627        /// ```
2628        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2629        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2630        #[must_use = "this returns the result of the operation, \
2631                      without modifying the original"]
2632        #[inline]
2633        pub const fn widening_mul(self, rhs: Self) -> (Self, Self) {
2634            Self::carrying_mul_add(self, rhs, 0, 0)
2635        }
2636
2637        /// Calculates the "full multiplication" `self * rhs + carry`
2638        /// without the possibility to overflow.
2639        ///
2640        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2641        /// of the result as two separate values, in that order.
2642        ///
2643        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2644        /// additional amount of overflow. This allows for chaining together multiple
2645        /// multiplications to create "big integers" which represent larger values.
2646        ///
2647        /// If you don't need the `carry`, then you can use [`Self::widening_mul`] instead.
2648        ///
2649        /// # Examples
2650        ///
2651        /// Please note that this example is shared between integer types.
2652        /// Which explains why `u32` is used here.
2653        ///
2654        /// ```
2655        /// #![feature(bigint_helper_methods)]
2656        /// assert_eq!(5u32.carrying_mul(2, 0), (10, 0));
2657        /// assert_eq!(5u32.carrying_mul(2, 10), (20, 0));
2658        /// assert_eq!(1_000_000_000u32.carrying_mul(10, 0), (1410065408, 2));
2659        /// assert_eq!(1_000_000_000u32.carrying_mul(10, 10), (1410065418, 2));
2660        #[doc = concat!("assert_eq!(",
2661            stringify!($SelfT), "::MAX.carrying_mul(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2662            "(0, ", stringify!($SelfT), "::MAX));"
2663        )]
2664        /// ```
2665        ///
2666        /// This is the core operation needed for scalar multiplication when
2667        /// implementing it for wider-than-native types.
2668        ///
2669        /// ```
2670        /// #![feature(bigint_helper_methods)]
2671        /// fn scalar_mul_eq(little_endian_digits: &mut Vec<u16>, multiplicand: u16) {
2672        ///     let mut carry = 0;
2673        ///     for d in little_endian_digits.iter_mut() {
2674        ///         (*d, carry) = d.carrying_mul(multiplicand, carry);
2675        ///     }
2676        ///     if carry != 0 {
2677        ///         little_endian_digits.push(carry);
2678        ///     }
2679        /// }
2680        ///
2681        /// let mut v = vec![10, 20];
2682        /// scalar_mul_eq(&mut v, 3);
2683        /// assert_eq!(v, [30, 60]);
2684        ///
2685        /// assert_eq!(0x87654321_u64 * 0xFEED, 0x86D3D159E38D);
2686        /// let mut v = vec![0x4321, 0x8765];
2687        /// scalar_mul_eq(&mut v, 0xFEED);
2688        /// assert_eq!(v, [0xE38D, 0xD159, 0x86D3]);
2689        /// ```
2690        ///
2691        /// If `carry` is zero, this is similar to [`overflowing_mul`](Self::overflowing_mul),
2692        /// except that it gives the value of the overflow instead of just whether one happened:
2693        ///
2694        /// ```
2695        /// #![feature(bigint_helper_methods)]
2696        /// let r = u8::carrying_mul(7, 13, 0);
2697        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(7, 13));
2698        /// let r = u8::carrying_mul(13, 42, 0);
2699        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(13, 42));
2700        /// ```
2701        ///
2702        /// The value of the first field in the returned tuple matches what you'd get
2703        /// by combining the [`wrapping_mul`](Self::wrapping_mul) and
2704        /// [`wrapping_add`](Self::wrapping_add) methods:
2705        ///
2706        /// ```
2707        /// #![feature(bigint_helper_methods)]
2708        /// assert_eq!(
2709        ///     789_u16.carrying_mul(456, 123).0,
2710        ///     789_u16.wrapping_mul(456).wrapping_add(123),
2711        /// );
2712        /// ```
2713        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2714        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2715        #[must_use = "this returns the result of the operation, \
2716                      without modifying the original"]
2717        #[inline]
2718        pub const fn carrying_mul(self, rhs: Self, carry: Self) -> (Self, Self) {
2719            Self::carrying_mul_add(self, rhs, carry, 0)
2720        }
2721
2722        /// Calculates the "full multiplication" `self * rhs + carry1 + carry2`
2723        /// without the possibility to overflow.
2724        ///
2725        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2726        /// of the result as two separate values, in that order.
2727        ///
2728        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2729        /// additional amount of overflow. This allows for chaining together multiple
2730        /// multiplications to create "big integers" which represent larger values.
2731        ///
2732        /// If you don't need either `carry`, then you can use [`Self::widening_mul`] instead,
2733        /// and if you only need one `carry`, then you can use [`Self::carrying_mul`] instead.
2734        ///
2735        /// # Examples
2736        ///
2737        /// Please note that this example is shared between integer types,
2738        /// which explains why `u32` is used here.
2739        ///
2740        /// ```
2741        /// #![feature(bigint_helper_methods)]
2742        /// assert_eq!(5u32.carrying_mul_add(2, 0, 0), (10, 0));
2743        /// assert_eq!(5u32.carrying_mul_add(2, 10, 10), (30, 0));
2744        /// assert_eq!(1_000_000_000u32.carrying_mul_add(10, 0, 0), (1410065408, 2));
2745        /// assert_eq!(1_000_000_000u32.carrying_mul_add(10, 10, 10), (1410065428, 2));
2746        #[doc = concat!("assert_eq!(",
2747            stringify!($SelfT), "::MAX.carrying_mul_add(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2748            "(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX));"
2749        )]
2750        /// ```
2751        ///
2752        /// This is the core per-digit operation for "grade school" O(n²) multiplication.
2753        ///
2754        /// Please note that this example is shared between integer types,
2755        /// using `u8` for simplicity of the demonstration.
2756        ///
2757        /// ```
2758        /// #![feature(bigint_helper_methods)]
2759        ///
2760        /// fn quadratic_mul<const N: usize>(a: [u8; N], b: [u8; N]) -> [u8; N] {
2761        ///     let mut out = [0; N];
2762        ///     for j in 0..N {
2763        ///         let mut carry = 0;
2764        ///         for i in 0..(N - j) {
2765        ///             (out[j + i], carry) = u8::carrying_mul_add(a[i], b[j], out[j + i], carry);
2766        ///         }
2767        ///     }
2768        ///     out
2769        /// }
2770        ///
2771        /// // -1 * -1 == 1
2772        /// assert_eq!(quadratic_mul([0xFF; 3], [0xFF; 3]), [1, 0, 0]);
2773        ///
2774        /// assert_eq!(u32::wrapping_mul(0x9e3779b9, 0x7f4a7c15), 0xCFFC982D);
2775        /// assert_eq!(
2776        ///     quadratic_mul(u32::to_le_bytes(0x9e3779b9), u32::to_le_bytes(0x7f4a7c15)),
2777        ///     u32::to_le_bytes(0xCFFC982D)
2778        /// );
2779        /// ```
2780        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2781        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2782        #[must_use = "this returns the result of the operation, \
2783                      without modifying the original"]
2784        #[inline]
2785        pub const fn carrying_mul_add(self, rhs: Self, carry: Self, add: Self) -> (Self, Self) {
2786            intrinsics::carrying_mul_add(self, rhs, carry, add)
2787        }
2788
2789        /// Calculates the divisor when `self` is divided by `rhs`.
2790        ///
2791        /// Returns a tuple of the divisor along with a boolean indicating
2792        /// whether an arithmetic overflow would occur. Note that for unsigned
2793        /// integers overflow never occurs, so the second value is always
2794        /// `false`.
2795        ///
2796        /// # Panics
2797        ///
2798        /// This function will panic if `rhs` is zero.
2799        ///
2800        /// # Examples
2801        ///
2802        /// ```
2803        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div(2), (2, false));")]
2804        /// ```
2805        #[inline(always)]
2806        #[stable(feature = "wrapping", since = "1.7.0")]
2807        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2808        #[must_use = "this returns the result of the operation, \
2809                      without modifying the original"]
2810        #[track_caller]
2811        pub const fn overflowing_div(self, rhs: Self) -> (Self, bool) {
2812            (self / rhs, false)
2813        }
2814
2815        /// Calculates the quotient of Euclidean division `self.div_euclid(rhs)`.
2816        ///
2817        /// Returns a tuple of the divisor along with a boolean indicating
2818        /// whether an arithmetic overflow would occur. Note that for unsigned
2819        /// integers overflow never occurs, so the second value is always
2820        /// `false`.
2821        /// Since, for the positive integers, all common
2822        /// definitions of division are equal, this
2823        /// is exactly equal to `self.overflowing_div(rhs)`.
2824        ///
2825        /// # Panics
2826        ///
2827        /// This function will panic if `rhs` is zero.
2828        ///
2829        /// # Examples
2830        ///
2831        /// ```
2832        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));")]
2833        /// ```
2834        #[inline(always)]
2835        #[stable(feature = "euclidean_division", since = "1.38.0")]
2836        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2837        #[must_use = "this returns the result of the operation, \
2838                      without modifying the original"]
2839        #[track_caller]
2840        pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) {
2841            (self / rhs, false)
2842        }
2843
2844        /// Calculates the remainder when `self` is divided by `rhs`.
2845        ///
2846        /// Returns a tuple of the remainder after dividing along with a boolean
2847        /// indicating whether an arithmetic overflow would occur. Note that for
2848        /// unsigned integers overflow never occurs, so the second value is
2849        /// always `false`.
2850        ///
2851        /// # Panics
2852        ///
2853        /// This function will panic if `rhs` is zero.
2854        ///
2855        /// # Examples
2856        ///
2857        /// ```
2858        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")]
2859        /// ```
2860        #[inline(always)]
2861        #[stable(feature = "wrapping", since = "1.7.0")]
2862        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2863        #[must_use = "this returns the result of the operation, \
2864                      without modifying the original"]
2865        #[track_caller]
2866        pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) {
2867            (self % rhs, false)
2868        }
2869
2870        /// Calculates the remainder `self.rem_euclid(rhs)` as if by Euclidean division.
2871        ///
2872        /// Returns a tuple of the modulo after dividing along with a boolean
2873        /// indicating whether an arithmetic overflow would occur. Note that for
2874        /// unsigned integers overflow never occurs, so the second value is
2875        /// always `false`.
2876        /// Since, for the positive integers, all common
2877        /// definitions of division are equal, this operation
2878        /// is exactly equal to `self.overflowing_rem(rhs)`.
2879        ///
2880        /// # Panics
2881        ///
2882        /// This function will panic if `rhs` is zero.
2883        ///
2884        /// # Examples
2885        ///
2886        /// ```
2887        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")]
2888        /// ```
2889        #[inline(always)]
2890        #[stable(feature = "euclidean_division", since = "1.38.0")]
2891        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2892        #[must_use = "this returns the result of the operation, \
2893                      without modifying the original"]
2894        #[track_caller]
2895        pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) {
2896            (self % rhs, false)
2897        }
2898
2899        /// Negates self in an overflowing fashion.
2900        ///
2901        /// Returns `!self + 1` using wrapping operations to return the value
2902        /// that represents the negation of this unsigned value. Note that for
2903        /// positive unsigned values overflow always occurs, but negating 0 does
2904        /// not overflow.
2905        ///
2906        /// # Examples
2907        ///
2908        /// ```
2909        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_neg(), (0, false));")]
2910        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".overflowing_neg(), (-2i32 as ", stringify!($SelfT), ", true));")]
2911        /// ```
2912        #[inline(always)]
2913        #[stable(feature = "wrapping", since = "1.7.0")]
2914        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2915        #[must_use = "this returns the result of the operation, \
2916                      without modifying the original"]
2917        pub const fn overflowing_neg(self) -> (Self, bool) {
2918            ((!self).wrapping_add(1), self != 0)
2919        }
2920
2921        /// Shifts self left by `rhs` bits.
2922        ///
2923        /// Returns a tuple of the shifted version of self along with a boolean
2924        /// indicating whether the shift value was larger than or equal to the
2925        /// number of bits. If the shift value is too large, then value is
2926        /// masked (N-1) where N is the number of bits, and this value is then
2927        /// used to perform the shift.
2928        ///
2929        /// # Examples
2930        ///
2931        /// ```
2932        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(4), (0x10, false));")]
2933        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(132), (0x10, true));")]
2934        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shl(", stringify!($BITS_MINUS_ONE), "), (0, false));")]
2935        /// ```
2936        #[stable(feature = "wrapping", since = "1.7.0")]
2937        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2938        #[must_use = "this returns the result of the operation, \
2939                      without modifying the original"]
2940        #[inline(always)]
2941        pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) {
2942            (self.wrapping_shl(rhs), rhs >= Self::BITS)
2943        }
2944
2945        /// Shifts self right by `rhs` bits.
2946        ///
2947        /// Returns a tuple of the shifted version of self along with a boolean
2948        /// indicating whether the shift value was larger than or equal to the
2949        /// number of bits. If the shift value is too large, then value is
2950        /// masked (N-1) where N is the number of bits, and this value is then
2951        /// used to perform the shift.
2952        ///
2953        /// # Examples
2954        ///
2955        /// ```
2956        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(4), (0x1, false));")]
2957        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(132), (0x1, true));")]
2958        /// ```
2959        #[stable(feature = "wrapping", since = "1.7.0")]
2960        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2961        #[must_use = "this returns the result of the operation, \
2962                      without modifying the original"]
2963        #[inline(always)]
2964        pub const fn overflowing_shr(self, rhs: u32) -> (Self, bool) {
2965            (self.wrapping_shr(rhs), rhs >= Self::BITS)
2966        }
2967
2968        /// Raises self to the power of `exp`, using exponentiation by squaring.
2969        ///
2970        /// Returns a tuple of the exponentiation along with a bool indicating
2971        /// whether an overflow happened.
2972        ///
2973        /// # Examples
2974        ///
2975        /// ```
2976        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".overflowing_pow(5), (243, false));")]
2977        /// assert_eq!(3u8.overflowing_pow(6), (217, true));
2978        /// ```
2979        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2980        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2981        #[must_use = "this returns the result of the operation, \
2982                      without modifying the original"]
2983        #[inline]
2984        pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) {
2985            if exp == 0{
2986                return (1,false);
2987            }
2988            let mut base = self;
2989            let mut acc: Self = 1;
2990            let mut overflown = false;
2991            // Scratch space for storing results of overflowing_mul.
2992            let mut r;
2993
2994            loop {
2995                if (exp & 1) == 1 {
2996                    r = acc.overflowing_mul(base);
2997                    // since exp!=0, finally the exp must be 1.
2998                    if exp == 1 {
2999                        r.1 |= overflown;
3000                        return r;
3001                    }
3002                    acc = r.0;
3003                    overflown |= r.1;
3004                }
3005                exp /= 2;
3006                r = base.overflowing_mul(base);
3007                base = r.0;
3008                overflown |= r.1;
3009            }
3010        }
3011
3012        /// Raises self to the power of `exp`, using exponentiation by squaring.
3013        ///
3014        /// # Examples
3015        ///
3016        /// ```
3017        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".pow(5), 32);")]
3018        /// ```
3019        #[stable(feature = "rust1", since = "1.0.0")]
3020        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3021        #[must_use = "this returns the result of the operation, \
3022                      without modifying the original"]
3023        #[inline]
3024        #[rustc_inherit_overflow_checks]
3025        pub const fn pow(self, mut exp: u32) -> Self {
3026            if exp == 0 {
3027                return 1;
3028            }
3029            let mut base = self;
3030            let mut acc = 1;
3031
3032            if intrinsics::is_val_statically_known(exp) {
3033                while exp > 1 {
3034                    if (exp & 1) == 1 {
3035                        acc = acc * base;
3036                    }
3037                    exp /= 2;
3038                    base = base * base;
3039                }
3040
3041                // since exp!=0, finally the exp must be 1.
3042                // Deal with the final bit of the exponent separately, since
3043                // squaring the base afterwards is not necessary and may cause a
3044                // needless overflow.
3045                acc * base
3046            } else {
3047                // This is faster than the above when the exponent is not known
3048                // at compile time. We can't use the same code for the constant
3049                // exponent case because LLVM is currently unable to unroll
3050                // this loop.
3051                loop {
3052                    if (exp & 1) == 1 {
3053                        acc = acc * base;
3054                        // since exp!=0, finally the exp must be 1.
3055                        if exp == 1 {
3056                            return acc;
3057                        }
3058                    }
3059                    exp /= 2;
3060                    base = base * base;
3061                }
3062            }
3063        }
3064
3065        /// Returns the square root of the number, rounded down.
3066        ///
3067        /// # Examples
3068        ///
3069        /// ```
3070        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".isqrt(), 3);")]
3071        /// ```
3072        #[stable(feature = "isqrt", since = "1.84.0")]
3073        #[rustc_const_stable(feature = "isqrt", since = "1.84.0")]
3074        #[must_use = "this returns the result of the operation, \
3075                      without modifying the original"]
3076        #[inline]
3077        pub const fn isqrt(self) -> Self {
3078            let result = crate::num::int_sqrt::$ActualT(self as $ActualT) as $SelfT;
3079
3080            // Inform the optimizer what the range of outputs is. If testing
3081            // `core` crashes with no panic message and a `num::int_sqrt::u*`
3082            // test failed, it's because your edits caused these assertions or
3083            // the assertions in `fn isqrt` of `nonzero.rs` to become false.
3084            //
3085            // SAFETY: Integer square root is a monotonically nondecreasing
3086            // function, which means that increasing the input will never
3087            // cause the output to decrease. Thus, since the input for unsigned
3088            // integers is bounded by `[0, <$ActualT>::MAX]`, sqrt(n) will be
3089            // bounded by `[sqrt(0), sqrt(<$ActualT>::MAX)]`.
3090            unsafe {
3091                const MAX_RESULT: $SelfT = crate::num::int_sqrt::$ActualT(<$ActualT>::MAX) as $SelfT;
3092                crate::hint::assert_unchecked(result <= MAX_RESULT);
3093            }
3094
3095            result
3096        }
3097
3098        /// Performs Euclidean division.
3099        ///
3100        /// Since, for the positive integers, all common
3101        /// definitions of division are equal, this
3102        /// is exactly equal to `self / rhs`.
3103        ///
3104        /// # Panics
3105        ///
3106        /// This function will panic if `rhs` is zero.
3107        ///
3108        /// # Examples
3109        ///
3110        /// ```
3111        #[doc = concat!("assert_eq!(7", stringify!($SelfT), ".div_euclid(4), 1); // or any other integer type")]
3112        /// ```
3113        #[stable(feature = "euclidean_division", since = "1.38.0")]
3114        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3115        #[must_use = "this returns the result of the operation, \
3116                      without modifying the original"]
3117        #[inline(always)]
3118        #[track_caller]
3119        pub const fn div_euclid(self, rhs: Self) -> Self {
3120            self / rhs
3121        }
3122
3123
3124        /// Calculates the least remainder of `self (mod rhs)`.
3125        ///
3126        /// Since, for the positive integers, all common
3127        /// definitions of division are equal, this
3128        /// is exactly equal to `self % rhs`.
3129        ///
3130        /// # Panics
3131        ///
3132        /// This function will panic if `rhs` is zero.
3133        ///
3134        /// # Examples
3135        ///
3136        /// ```
3137        #[doc = concat!("assert_eq!(7", stringify!($SelfT), ".rem_euclid(4), 3); // or any other integer type")]
3138        /// ```
3139        #[doc(alias = "modulo", alias = "mod")]
3140        #[stable(feature = "euclidean_division", since = "1.38.0")]
3141        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3142        #[must_use = "this returns the result of the operation, \
3143                      without modifying the original"]
3144        #[inline(always)]
3145        #[track_caller]
3146        pub const fn rem_euclid(self, rhs: Self) -> Self {
3147            self % rhs
3148        }
3149
3150        /// Calculates the quotient of `self` and `rhs`, rounding the result towards negative infinity.
3151        ///
3152        /// This is the same as performing `self / rhs` for all unsigned integers.
3153        ///
3154        /// # Panics
3155        ///
3156        /// This function will panic if `rhs` is zero.
3157        ///
3158        /// # Examples
3159        ///
3160        /// ```
3161        /// #![feature(int_roundings)]
3162        #[doc = concat!("assert_eq!(7_", stringify!($SelfT), ".div_floor(4), 1);")]
3163        /// ```
3164        #[unstable(feature = "int_roundings", issue = "88581")]
3165        #[must_use = "this returns the result of the operation, \
3166                      without modifying the original"]
3167        #[inline(always)]
3168        #[track_caller]
3169        pub const fn div_floor(self, rhs: Self) -> Self {
3170            self / rhs
3171        }
3172
3173        /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity.
3174        ///
3175        /// # Panics
3176        ///
3177        /// This function will panic if `rhs` is zero.
3178        ///
3179        /// # Examples
3180        ///
3181        /// ```
3182        #[doc = concat!("assert_eq!(7_", stringify!($SelfT), ".div_ceil(4), 2);")]
3183        /// ```
3184        #[stable(feature = "int_roundings1", since = "1.73.0")]
3185        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3186        #[must_use = "this returns the result of the operation, \
3187                      without modifying the original"]
3188        #[inline]
3189        #[track_caller]
3190        pub const fn div_ceil(self, rhs: Self) -> Self {
3191            let d = self / rhs;
3192            let r = self % rhs;
3193            if r > 0 {
3194                d + 1
3195            } else {
3196                d
3197            }
3198        }
3199
3200        /// Calculates the smallest value greater than or equal to `self` that
3201        /// is a multiple of `rhs`.
3202        ///
3203        /// # Panics
3204        ///
3205        /// This function will panic if `rhs` is zero.
3206        ///
3207        /// ## Overflow behavior
3208        ///
3209        /// On overflow, this function will panic if overflow checks are enabled (default in debug
3210        /// mode) and wrap if overflow checks are disabled (default in release mode).
3211        ///
3212        /// # Examples
3213        ///
3214        /// ```
3215        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(8), 16);")]
3216        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(8), 24);")]
3217        /// ```
3218        #[stable(feature = "int_roundings1", since = "1.73.0")]
3219        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3220        #[must_use = "this returns the result of the operation, \
3221                      without modifying the original"]
3222        #[inline]
3223        #[rustc_inherit_overflow_checks]
3224        pub const fn next_multiple_of(self, rhs: Self) -> Self {
3225            match self % rhs {
3226                0 => self,
3227                r => self + (rhs - r)
3228            }
3229        }
3230
3231        /// Calculates the smallest value greater than or equal to `self` that
3232        /// is a multiple of `rhs`. Returns `None` if `rhs` is zero or the
3233        /// operation would result in overflow.
3234        ///
3235        /// # Examples
3236        ///
3237        /// ```
3238        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(16));")]
3239        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(24));")]
3240        #[doc = concat!("assert_eq!(1_", stringify!($SelfT), ".checked_next_multiple_of(0), None);")]
3241        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_multiple_of(2), None);")]
3242        /// ```
3243        #[stable(feature = "int_roundings1", since = "1.73.0")]
3244        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3245        #[must_use = "this returns the result of the operation, \
3246                      without modifying the original"]
3247        #[inline]
3248        pub const fn checked_next_multiple_of(self, rhs: Self) -> Option<Self> {
3249            match try_opt!(self.checked_rem(rhs)) {
3250                0 => Some(self),
3251                // rhs - r cannot overflow because r is smaller than rhs
3252                r => self.checked_add(rhs - r)
3253            }
3254        }
3255
3256        /// Returns `true` if `self` is an integer multiple of `rhs`, and false otherwise.
3257        ///
3258        /// This function is equivalent to `self % rhs == 0`, except that it will not panic
3259        /// for `rhs == 0`. Instead, `0.is_multiple_of(0) == true`, and for any non-zero `n`,
3260        /// `n.is_multiple_of(0) == false`.
3261        ///
3262        /// # Examples
3263        ///
3264        /// ```
3265        #[doc = concat!("assert!(6_", stringify!($SelfT), ".is_multiple_of(2));")]
3266        #[doc = concat!("assert!(!5_", stringify!($SelfT), ".is_multiple_of(2));")]
3267        ///
3268        #[doc = concat!("assert!(0_", stringify!($SelfT), ".is_multiple_of(0));")]
3269        #[doc = concat!("assert!(!6_", stringify!($SelfT), ".is_multiple_of(0));")]
3270        /// ```
3271        #[stable(feature = "unsigned_is_multiple_of", since = "1.87.0")]
3272        #[rustc_const_stable(feature = "unsigned_is_multiple_of", since = "1.87.0")]
3273        #[must_use]
3274        #[inline]
3275        #[rustc_inherit_overflow_checks]
3276        pub const fn is_multiple_of(self, rhs: Self) -> bool {
3277            match rhs {
3278                0 => self == 0,
3279                _ => self % rhs == 0,
3280            }
3281        }
3282
3283        /// Returns `true` if and only if `self == 2^k` for some unsigned integer `k`.
3284        ///
3285        /// # Examples
3286        ///
3287        /// ```
3288        #[doc = concat!("assert!(16", stringify!($SelfT), ".is_power_of_two());")]
3289        #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_power_of_two());")]
3290        /// ```
3291        #[must_use]
3292        #[stable(feature = "rust1", since = "1.0.0")]
3293        #[rustc_const_stable(feature = "const_is_power_of_two", since = "1.32.0")]
3294        #[inline(always)]
3295        pub const fn is_power_of_two(self) -> bool {
3296            self.count_ones() == 1
3297        }
3298
3299        // Returns one less than next power of two.
3300        // (For 8u8 next power of two is 8u8 and for 6u8 it is 8u8)
3301        //
3302        // 8u8.one_less_than_next_power_of_two() == 7
3303        // 6u8.one_less_than_next_power_of_two() == 7
3304        //
3305        // This method cannot overflow, as in the `next_power_of_two`
3306        // overflow cases it instead ends up returning the maximum value
3307        // of the type, and can return 0 for 0.
3308        #[inline]
3309        const fn one_less_than_next_power_of_two(self) -> Self {
3310            if self <= 1 { return 0; }
3311
3312            let p = self - 1;
3313            // SAFETY: Because `p > 0`, it cannot consist entirely of leading zeros.
3314            // That means the shift is always in-bounds, and some processors
3315            // (such as intel pre-haswell) have more efficient ctlz
3316            // intrinsics when the argument is non-zero.
3317            let z = unsafe { intrinsics::ctlz_nonzero(p) };
3318            <$SelfT>::MAX >> z
3319        }
3320
3321        /// Returns the smallest power of two greater than or equal to `self`.
3322        ///
3323        /// When return value overflows (i.e., `self > (1 << (N-1))` for type
3324        /// `uN`), it panics in debug mode and the return value is wrapped to 0 in
3325        /// release mode (the only situation in which this method can return 0).
3326        ///
3327        /// # Examples
3328        ///
3329        /// ```
3330        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".next_power_of_two(), 2);")]
3331        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".next_power_of_two(), 4);")]
3332        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".next_power_of_two(), 1);")]
3333        /// ```
3334        #[stable(feature = "rust1", since = "1.0.0")]
3335        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3336        #[must_use = "this returns the result of the operation, \
3337                      without modifying the original"]
3338        #[inline]
3339        #[rustc_inherit_overflow_checks]
3340        pub const fn next_power_of_two(self) -> Self {
3341            self.one_less_than_next_power_of_two() + 1
3342        }
3343
3344        /// Returns the smallest power of two greater than or equal to `self`. If
3345        /// the next power of two is greater than the type's maximum value,
3346        /// `None` is returned, otherwise the power of two is wrapped in `Some`.
3347        ///
3348        /// # Examples
3349        ///
3350        /// ```
3351        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_next_power_of_two(), Some(2));")]
3352        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".checked_next_power_of_two(), Some(4));")]
3353        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_power_of_two(), None);")]
3354        /// ```
3355        #[inline]
3356        #[stable(feature = "rust1", since = "1.0.0")]
3357        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3358        #[must_use = "this returns the result of the operation, \
3359                      without modifying the original"]
3360        pub const fn checked_next_power_of_two(self) -> Option<Self> {
3361            self.one_less_than_next_power_of_two().checked_add(1)
3362        }
3363
3364        /// Returns the smallest power of two greater than or equal to `n`. If
3365        /// the next power of two is greater than the type's maximum value,
3366        /// the return value is wrapped to `0`.
3367        ///
3368        /// # Examples
3369        ///
3370        /// ```
3371        /// #![feature(wrapping_next_power_of_two)]
3372        ///
3373        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".wrapping_next_power_of_two(), 2);")]
3374        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_next_power_of_two(), 4);")]
3375        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_next_power_of_two(), 0);")]
3376        /// ```
3377        #[inline]
3378        #[unstable(feature = "wrapping_next_power_of_two", issue = "32463",
3379                   reason = "needs decision on wrapping behavior")]
3380        #[must_use = "this returns the result of the operation, \
3381                      without modifying the original"]
3382        pub const fn wrapping_next_power_of_two(self) -> Self {
3383            self.one_less_than_next_power_of_two().wrapping_add(1)
3384        }
3385
3386        /// Returns the memory representation of this integer as a byte array in
3387        /// big-endian (network) byte order.
3388        ///
3389        #[doc = $to_xe_bytes_doc]
3390        ///
3391        /// # Examples
3392        ///
3393        /// ```
3394        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_be_bytes();")]
3395        #[doc = concat!("assert_eq!(bytes, ", $be_bytes, ");")]
3396        /// ```
3397        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3398        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3399        #[must_use = "this returns the result of the operation, \
3400                      without modifying the original"]
3401        #[inline]
3402        pub const fn to_be_bytes(self) -> [u8; size_of::<Self>()] {
3403            self.to_be().to_ne_bytes()
3404        }
3405
3406        /// Returns the memory representation of this integer as a byte array in
3407        /// little-endian byte order.
3408        ///
3409        #[doc = $to_xe_bytes_doc]
3410        ///
3411        /// # Examples
3412        ///
3413        /// ```
3414        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_le_bytes();")]
3415        #[doc = concat!("assert_eq!(bytes, ", $le_bytes, ");")]
3416        /// ```
3417        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3418        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3419        #[must_use = "this returns the result of the operation, \
3420                      without modifying the original"]
3421        #[inline]
3422        pub const fn to_le_bytes(self) -> [u8; size_of::<Self>()] {
3423            self.to_le().to_ne_bytes()
3424        }
3425
3426        /// Returns the memory representation of this integer as a byte array in
3427        /// native byte order.
3428        ///
3429        /// As the target platform's native endianness is used, portable code
3430        /// should use [`to_be_bytes`] or [`to_le_bytes`], as appropriate,
3431        /// instead.
3432        ///
3433        #[doc = $to_xe_bytes_doc]
3434        ///
3435        /// [`to_be_bytes`]: Self::to_be_bytes
3436        /// [`to_le_bytes`]: Self::to_le_bytes
3437        ///
3438        /// # Examples
3439        ///
3440        /// ```
3441        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_ne_bytes();")]
3442        /// assert_eq!(
3443        ///     bytes,
3444        ///     if cfg!(target_endian = "big") {
3445        #[doc = concat!("        ", $be_bytes)]
3446        ///     } else {
3447        #[doc = concat!("        ", $le_bytes)]
3448        ///     }
3449        /// );
3450        /// ```
3451        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3452        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3453        #[must_use = "this returns the result of the operation, \
3454                      without modifying the original"]
3455        #[allow(unnecessary_transmutes)]
3456        // SAFETY: const sound because integers are plain old datatypes so we can always
3457        // transmute them to arrays of bytes
3458        #[inline]
3459        pub const fn to_ne_bytes(self) -> [u8; size_of::<Self>()] {
3460            // SAFETY: integers are plain old datatypes so we can always transmute them to
3461            // arrays of bytes
3462            unsafe { mem::transmute(self) }
3463        }
3464
3465        /// Creates a native endian integer value from its representation
3466        /// as a byte array in big endian.
3467        ///
3468        #[doc = $from_xe_bytes_doc]
3469        ///
3470        /// # Examples
3471        ///
3472        /// ```
3473        #[doc = concat!("let value = ", stringify!($SelfT), "::from_be_bytes(", $be_bytes, ");")]
3474        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3475        /// ```
3476        ///
3477        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3478        ///
3479        /// ```
3480        #[doc = concat!("fn read_be_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3481        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3482        ///     *input = rest;
3483        #[doc = concat!("    ", stringify!($SelfT), "::from_be_bytes(int_bytes.try_into().unwrap())")]
3484        /// }
3485        /// ```
3486        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3487        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3488        #[must_use]
3489        #[inline]
3490        pub const fn from_be_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3491            Self::from_be(Self::from_ne_bytes(bytes))
3492        }
3493
3494        /// Creates a native endian integer value from its representation
3495        /// as a byte array in little endian.
3496        ///
3497        #[doc = $from_xe_bytes_doc]
3498        ///
3499        /// # Examples
3500        ///
3501        /// ```
3502        #[doc = concat!("let value = ", stringify!($SelfT), "::from_le_bytes(", $le_bytes, ");")]
3503        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3504        /// ```
3505        ///
3506        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3507        ///
3508        /// ```
3509        #[doc = concat!("fn read_le_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3510        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3511        ///     *input = rest;
3512        #[doc = concat!("    ", stringify!($SelfT), "::from_le_bytes(int_bytes.try_into().unwrap())")]
3513        /// }
3514        /// ```
3515        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3516        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3517        #[must_use]
3518        #[inline]
3519        pub const fn from_le_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3520            Self::from_le(Self::from_ne_bytes(bytes))
3521        }
3522
3523        /// Creates a native endian integer value from its memory representation
3524        /// as a byte array in native endianness.
3525        ///
3526        /// As the target platform's native endianness is used, portable code
3527        /// likely wants to use [`from_be_bytes`] or [`from_le_bytes`], as
3528        /// appropriate instead.
3529        ///
3530        /// [`from_be_bytes`]: Self::from_be_bytes
3531        /// [`from_le_bytes`]: Self::from_le_bytes
3532        ///
3533        #[doc = $from_xe_bytes_doc]
3534        ///
3535        /// # Examples
3536        ///
3537        /// ```
3538        #[doc = concat!("let value = ", stringify!($SelfT), "::from_ne_bytes(if cfg!(target_endian = \"big\") {")]
3539        #[doc = concat!("    ", $be_bytes, "")]
3540        /// } else {
3541        #[doc = concat!("    ", $le_bytes, "")]
3542        /// });
3543        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3544        /// ```
3545        ///
3546        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3547        ///
3548        /// ```
3549        #[doc = concat!("fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3550        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3551        ///     *input = rest;
3552        #[doc = concat!("    ", stringify!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())")]
3553        /// }
3554        /// ```
3555        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3556        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3557        #[allow(unnecessary_transmutes)]
3558        #[must_use]
3559        // SAFETY: const sound because integers are plain old datatypes so we can always
3560        // transmute to them
3561        #[inline]
3562        pub const fn from_ne_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3563            // SAFETY: integers are plain old datatypes so we can always transmute to them
3564            unsafe { mem::transmute(bytes) }
3565        }
3566
3567        /// New code should prefer to use
3568        #[doc = concat!("[`", stringify!($SelfT), "::MIN", "`] instead.")]
3569        ///
3570        /// Returns the smallest value that can be represented by this integer type.
3571        #[stable(feature = "rust1", since = "1.0.0")]
3572        #[rustc_promotable]
3573        #[inline(always)]
3574        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3575        #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")]
3576        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value")]
3577        pub const fn min_value() -> Self { Self::MIN }
3578
3579        /// New code should prefer to use
3580        #[doc = concat!("[`", stringify!($SelfT), "::MAX", "`] instead.")]
3581        ///
3582        /// Returns the largest value that can be represented by this integer type.
3583        #[stable(feature = "rust1", since = "1.0.0")]
3584        #[rustc_promotable]
3585        #[inline(always)]
3586        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3587        #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")]
3588        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value")]
3589        pub const fn max_value() -> Self { Self::MAX }
3590    }
3591}