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!($BITS), ");")]
53        /// ```
54        #[stable(feature = "int_bits_const", since = "1.53.0")]
55        #[cfg(not(feature = "ferrocene_certified"))]
56        pub const BITS: u32 = Self::MAX.count_ones();
57
58        /// Returns the number of ones in the binary representation of `self`.
59        ///
60        /// # Examples
61        ///
62        /// ```
63        #[doc = concat!("let n = 0b01001100", stringify!($SelfT), ";")]
64        /// assert_eq!(n.count_ones(), 3);
65        ///
66        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
67        #[doc = concat!("assert_eq!(max.count_ones(), ", stringify!($BITS), ");")]
68        ///
69        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
70        /// assert_eq!(zero.count_ones(), 0);
71        /// ```
72        #[stable(feature = "rust1", since = "1.0.0")]
73        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
74        #[doc(alias = "popcount")]
75        #[doc(alias = "popcnt")]
76        #[must_use = "this returns the result of the operation, \
77                      without modifying the original"]
78        #[inline(always)]
79        pub const fn count_ones(self) -> u32 {
80            return intrinsics::ctpop(self);
81        }
82
83        /// Returns the number of zeros in the binary representation of `self`.
84        ///
85        /// # Examples
86        ///
87        /// ```
88        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
89        #[doc = concat!("assert_eq!(zero.count_zeros(), ", stringify!($BITS), ");")]
90        ///
91        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
92        /// assert_eq!(max.count_zeros(), 0);
93        /// ```
94        #[stable(feature = "rust1", since = "1.0.0")]
95        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
96        #[must_use = "this returns the result of the operation, \
97                      without modifying the original"]
98        #[inline(always)]
99        #[cfg(not(feature = "ferrocene_certified"))]
100        pub const fn count_zeros(self) -> u32 {
101            (!self).count_ones()
102        }
103
104        /// Returns the number of leading zeros in the binary representation of `self`.
105        ///
106        /// Depending on what you're doing with the value, you might also be interested in the
107        /// [`ilog2`] function which returns a consistent number, even if the type widens.
108        ///
109        /// # Examples
110        ///
111        /// ```
112        #[doc = concat!("let n = ", stringify!($SelfT), "::MAX >> 2;")]
113        /// assert_eq!(n.leading_zeros(), 2);
114        ///
115        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
116        #[doc = concat!("assert_eq!(zero.leading_zeros(), ", stringify!($BITS), ");")]
117        ///
118        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
119        /// assert_eq!(max.leading_zeros(), 0);
120        /// ```
121        #[doc = concat!("[`ilog2`]: ", stringify!($SelfT), "::ilog2")]
122        #[stable(feature = "rust1", since = "1.0.0")]
123        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
124        #[must_use = "this returns the result of the operation, \
125                      without modifying the original"]
126        #[inline(always)]
127        #[cfg(not(feature = "ferrocene_certified"))]
128        pub const fn leading_zeros(self) -> u32 {
129            return intrinsics::ctlz(self as $ActualT);
130        }
131
132        /// Returns the number of trailing zeros in the binary representation
133        /// of `self`.
134        ///
135        /// # Examples
136        ///
137        /// ```
138        #[doc = concat!("let n = 0b0101000", stringify!($SelfT), ";")]
139        /// assert_eq!(n.trailing_zeros(), 3);
140        ///
141        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
142        #[doc = concat!("assert_eq!(zero.trailing_zeros(), ", stringify!($BITS), ");")]
143        ///
144        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
145        #[doc = concat!("assert_eq!(max.trailing_zeros(), 0);")]
146        /// ```
147        #[stable(feature = "rust1", since = "1.0.0")]
148        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
149        #[must_use = "this returns the result of the operation, \
150                      without modifying the original"]
151        #[inline(always)]
152        #[cfg(not(feature = "ferrocene_certified"))]
153        pub const fn trailing_zeros(self) -> u32 {
154            return intrinsics::cttz(self);
155        }
156
157        /// Returns the number of leading ones in the binary representation of `self`.
158        ///
159        /// # Examples
160        ///
161        /// ```
162        #[doc = concat!("let n = !(", stringify!($SelfT), "::MAX >> 2);")]
163        /// assert_eq!(n.leading_ones(), 2);
164        ///
165        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
166        /// assert_eq!(zero.leading_ones(), 0);
167        ///
168        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
169        #[doc = concat!("assert_eq!(max.leading_ones(), ", stringify!($BITS), ");")]
170        /// ```
171        #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
172        #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
173        #[must_use = "this returns the result of the operation, \
174                      without modifying the original"]
175        #[inline(always)]
176        #[cfg(not(feature = "ferrocene_certified"))]
177        pub const fn leading_ones(self) -> u32 {
178            (!self).leading_zeros()
179        }
180
181        /// Returns the number of trailing ones in the binary representation
182        /// of `self`.
183        ///
184        /// # Examples
185        ///
186        /// ```
187        #[doc = concat!("let n = 0b1010111", stringify!($SelfT), ";")]
188        /// assert_eq!(n.trailing_ones(), 3);
189        ///
190        #[doc = concat!("let zero = 0", stringify!($SelfT), ";")]
191        /// assert_eq!(zero.trailing_ones(), 0);
192        ///
193        #[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
194        #[doc = concat!("assert_eq!(max.trailing_ones(), ", stringify!($BITS), ");")]
195        /// ```
196        #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
197        #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
198        #[must_use = "this returns the result of the operation, \
199                      without modifying the original"]
200        #[inline(always)]
201        #[cfg(not(feature = "ferrocene_certified"))]
202        pub const fn trailing_ones(self) -> u32 {
203            (!self).trailing_zeros()
204        }
205
206        /// Returns the minimum number of bits required to represent `self`.
207        ///
208        /// This method returns zero if `self` is zero.
209        ///
210        /// # Examples
211        ///
212        /// ```
213        /// #![feature(uint_bit_width)]
214        ///
215        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".bit_width(), 0);")]
216        #[doc = concat!("assert_eq!(0b111_", stringify!($SelfT), ".bit_width(), 3);")]
217        #[doc = concat!("assert_eq!(0b1110_", stringify!($SelfT), ".bit_width(), 4);")]
218        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.bit_width(), ", stringify!($BITS), ");")]
219        /// ```
220        #[unstable(feature = "uint_bit_width", issue = "142326")]
221        #[must_use = "this returns the result of the operation, \
222                      without modifying the original"]
223        #[inline(always)]
224        #[cfg(not(feature = "ferrocene_certified"))]
225        pub const fn bit_width(self) -> u32 {
226            Self::BITS - self.leading_zeros()
227        }
228
229        /// Returns `self` with only the most significant bit set, or `0` if
230        /// the input is `0`.
231        ///
232        /// # Examples
233        ///
234        /// ```
235        /// #![feature(isolate_most_least_significant_one)]
236        ///
237        #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
238        ///
239        /// assert_eq!(n.isolate_most_significant_one(), 0b_01000000);
240        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_most_significant_one(), 0);")]
241        /// ```
242        #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
243        #[must_use = "this returns the result of the operation, \
244                      without modifying the original"]
245        #[inline(always)]
246        #[cfg(not(feature = "ferrocene_certified"))]
247        pub const fn isolate_most_significant_one(self) -> Self {
248            self & (((1 as $SelfT) << (<$SelfT>::BITS - 1)).wrapping_shr(self.leading_zeros()))
249        }
250
251        /// Returns `self` with only the least significant bit set, or `0` if
252        /// the input is `0`.
253        ///
254        /// # Examples
255        ///
256        /// ```
257        /// #![feature(isolate_most_least_significant_one)]
258        ///
259        #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
260        ///
261        /// assert_eq!(n.isolate_least_significant_one(), 0b_00000100);
262        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_least_significant_one(), 0);")]
263        /// ```
264        #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
265        #[must_use = "this returns the result of the operation, \
266                      without modifying the original"]
267        #[inline(always)]
268        #[cfg(not(feature = "ferrocene_certified"))]
269        pub const fn isolate_least_significant_one(self) -> Self {
270            self & self.wrapping_neg()
271        }
272
273        /// Returns the bit pattern of `self` reinterpreted as a signed integer of the same size.
274        ///
275        /// This produces the same result as an `as` cast, but ensures that the bit-width remains
276        /// the same.
277        ///
278        /// # Examples
279        ///
280        /// ```
281        #[doc = concat!("let n = ", stringify!($SelfT), "::MAX;")]
282        ///
283        #[doc = concat!("assert_eq!(n.cast_signed(), -1", stringify!($SignedT), ");")]
284        /// ```
285        #[stable(feature = "integer_sign_cast", since = "1.87.0")]
286        #[rustc_const_stable(feature = "integer_sign_cast", since = "1.87.0")]
287        #[must_use = "this returns the result of the operation, \
288                      without modifying the original"]
289        #[inline(always)]
290        #[cfg(not(feature = "ferrocene_certified"))]
291        pub const fn cast_signed(self) -> $SignedT {
292            self as $SignedT
293        }
294
295        /// Shifts the bits to the left by a specified amount, `n`,
296        /// wrapping the truncated bits to the end of the resulting integer.
297        ///
298        /// Please note this isn't the same operation as the `<<` shifting operator!
299        ///
300        /// # Examples
301        ///
302        /// ```
303        #[doc = concat!("let n = ", $rot_op, stringify!($SelfT), ";")]
304        #[doc = concat!("let m = ", $rot_result, ";")]
305        ///
306        #[doc = concat!("assert_eq!(n.rotate_left(", $rot, "), m);")]
307        /// ```
308        #[stable(feature = "rust1", since = "1.0.0")]
309        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
310        #[must_use = "this returns the result of the operation, \
311                      without modifying the original"]
312        #[inline(always)]
313        #[cfg(not(feature = "ferrocene_certified"))]
314        pub const fn rotate_left(self, n: u32) -> Self {
315            return intrinsics::rotate_left(self, n);
316        }
317
318        /// Shifts the bits to the right by a specified amount, `n`,
319        /// wrapping the truncated bits to the beginning of the resulting
320        /// integer.
321        ///
322        /// Please note this isn't the same operation as the `>>` shifting operator!
323        ///
324        /// # Examples
325        ///
326        /// ```
327        #[doc = concat!("let n = ", $rot_result, stringify!($SelfT), ";")]
328        #[doc = concat!("let m = ", $rot_op, ";")]
329        ///
330        #[doc = concat!("assert_eq!(n.rotate_right(", $rot, "), m);")]
331        /// ```
332        #[stable(feature = "rust1", since = "1.0.0")]
333        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
334        #[must_use = "this returns the result of the operation, \
335                      without modifying the original"]
336        #[inline(always)]
337        #[cfg(not(feature = "ferrocene_certified"))]
338        pub const fn rotate_right(self, n: u32) -> Self {
339            return intrinsics::rotate_right(self, n);
340        }
341
342        /// Reverses the byte order of the integer.
343        ///
344        /// # Examples
345        ///
346        /// ```
347        #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")]
348        /// let m = n.swap_bytes();
349        ///
350        #[doc = concat!("assert_eq!(m, ", $swapped, ");")]
351        /// ```
352        #[stable(feature = "rust1", since = "1.0.0")]
353        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
354        #[must_use = "this returns the result of the operation, \
355                      without modifying the original"]
356        #[inline(always)]
357        #[cfg(not(feature = "ferrocene_certified"))]
358        pub const fn swap_bytes(self) -> Self {
359            intrinsics::bswap(self as $ActualT) as Self
360        }
361
362        /// Reverses the order of bits in the integer. The least significant bit becomes the most significant bit,
363        ///                 second least-significant bit becomes second most-significant bit, etc.
364        ///
365        /// # Examples
366        ///
367        /// ```
368        #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")]
369        /// let m = n.reverse_bits();
370        ///
371        #[doc = concat!("assert_eq!(m, ", $reversed, ");")]
372        #[doc = concat!("assert_eq!(0, 0", stringify!($SelfT), ".reverse_bits());")]
373        /// ```
374        #[stable(feature = "reverse_bits", since = "1.37.0")]
375        #[rustc_const_stable(feature = "reverse_bits", since = "1.37.0")]
376        #[must_use = "this returns the result of the operation, \
377                      without modifying the original"]
378        #[inline(always)]
379        #[cfg(not(feature = "ferrocene_certified"))]
380        pub const fn reverse_bits(self) -> Self {
381            intrinsics::bitreverse(self as $ActualT) as Self
382        }
383
384        /// Converts an integer from big endian to the target's endianness.
385        ///
386        /// On big endian this is a no-op. On little endian the bytes are
387        /// swapped.
388        ///
389        /// # Examples
390        ///
391        /// ```
392        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
393        ///
394        /// if cfg!(target_endian = "big") {
395        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_be(n), n)")]
396        /// } else {
397        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_be(n), n.swap_bytes())")]
398        /// }
399        /// ```
400        #[stable(feature = "rust1", since = "1.0.0")]
401        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
402        #[must_use]
403        #[inline(always)]
404        #[cfg(not(feature = "ferrocene_certified"))]
405        pub const fn from_be(x: Self) -> Self {
406            #[cfg(target_endian = "big")]
407            {
408                x
409            }
410            #[cfg(not(target_endian = "big"))]
411            {
412                x.swap_bytes()
413            }
414        }
415
416        /// Converts an integer from little endian to the target's endianness.
417        ///
418        /// On little endian this is a no-op. On big endian the bytes are
419        /// swapped.
420        ///
421        /// # Examples
422        ///
423        /// ```
424        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
425        ///
426        /// if cfg!(target_endian = "little") {
427        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_le(n), n)")]
428        /// } else {
429        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_le(n), n.swap_bytes())")]
430        /// }
431        /// ```
432        #[stable(feature = "rust1", since = "1.0.0")]
433        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
434        #[must_use]
435        #[inline(always)]
436        #[cfg(not(feature = "ferrocene_certified"))]
437        pub const fn from_le(x: Self) -> Self {
438            #[cfg(target_endian = "little")]
439            {
440                x
441            }
442            #[cfg(not(target_endian = "little"))]
443            {
444                x.swap_bytes()
445            }
446        }
447
448        /// Converts `self` to big endian from the target's endianness.
449        ///
450        /// On big endian this is a no-op. On little endian the bytes are
451        /// swapped.
452        ///
453        /// # Examples
454        ///
455        /// ```
456        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
457        ///
458        /// if cfg!(target_endian = "big") {
459        ///     assert_eq!(n.to_be(), n)
460        /// } else {
461        ///     assert_eq!(n.to_be(), n.swap_bytes())
462        /// }
463        /// ```
464        #[stable(feature = "rust1", since = "1.0.0")]
465        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
466        #[must_use = "this returns the result of the operation, \
467                      without modifying the original"]
468        #[inline(always)]
469        #[cfg(not(feature = "ferrocene_certified"))]
470        pub const fn to_be(self) -> Self { // or not to be?
471            #[cfg(target_endian = "big")]
472            {
473                self
474            }
475            #[cfg(not(target_endian = "big"))]
476            {
477                self.swap_bytes()
478            }
479        }
480
481        /// Converts `self` to little endian from the target's endianness.
482        ///
483        /// On little endian this is a no-op. On big endian the bytes are
484        /// swapped.
485        ///
486        /// # Examples
487        ///
488        /// ```
489        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
490        ///
491        /// if cfg!(target_endian = "little") {
492        ///     assert_eq!(n.to_le(), n)
493        /// } else {
494        ///     assert_eq!(n.to_le(), n.swap_bytes())
495        /// }
496        /// ```
497        #[stable(feature = "rust1", since = "1.0.0")]
498        #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
499        #[must_use = "this returns the result of the operation, \
500                      without modifying the original"]
501        #[inline(always)]
502        #[cfg(not(feature = "ferrocene_certified"))]
503        pub const fn to_le(self) -> Self {
504            #[cfg(target_endian = "little")]
505            {
506                self
507            }
508            #[cfg(not(target_endian = "little"))]
509            {
510                self.swap_bytes()
511            }
512        }
513
514        /// Checked integer addition. Computes `self + rhs`, returning `None`
515        /// if overflow occurred.
516        ///
517        /// # Examples
518        ///
519        /// ```
520        #[doc = concat!(
521            "assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(1), ",
522            "Some(", stringify!($SelfT), "::MAX - 1));"
523        )]
524        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(3), None);")]
525        /// ```
526        #[stable(feature = "rust1", since = "1.0.0")]
527        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
528        #[must_use = "this returns the result of the operation, \
529                      without modifying the original"]
530        #[inline]
531        #[cfg(not(feature = "ferrocene_certified"))]
532        pub const fn checked_add(self, rhs: Self) -> Option<Self> {
533            // This used to use `overflowing_add`, but that means it ends up being
534            // a `wrapping_add`, losing some optimization opportunities. Notably,
535            // phrasing it this way helps `.checked_add(1)` optimize to a check
536            // against `MAX` and a `add nuw`.
537            // Per <https://github.com/rust-lang/rust/pull/124114#issuecomment-2066173305>,
538            // LLVM is happy to re-form the intrinsic later if useful.
539
540            if intrinsics::unlikely(intrinsics::add_with_overflow(self, rhs).1) {
541                None
542            } else {
543                // SAFETY: Just checked it doesn't overflow
544                Some(unsafe { intrinsics::unchecked_add(self, rhs) })
545            }
546        }
547
548        /// Strict integer addition. Computes `self + rhs`, panicking
549        /// if overflow occurred.
550        ///
551        /// # Panics
552        ///
553        /// ## Overflow behavior
554        ///
555        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
556        ///
557        /// # Examples
558        ///
559        /// ```
560        /// #![feature(strict_overflow_ops)]
561        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).strict_add(1), ", stringify!($SelfT), "::MAX - 1);")]
562        /// ```
563        ///
564        /// The following panics because of overflow:
565        ///
566        /// ```should_panic
567        /// #![feature(strict_overflow_ops)]
568        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add(3);")]
569        /// ```
570        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
571        #[must_use = "this returns the result of the operation, \
572                      without modifying the original"]
573        #[inline]
574        #[track_caller]
575        #[cfg(not(feature = "ferrocene_certified"))]
576        pub const fn strict_add(self, rhs: Self) -> Self {
577            let (a, b) = self.overflowing_add(rhs);
578            if b { overflow_panic::add() } else { a }
579        }
580
581        /// Unchecked integer addition. Computes `self + rhs`, assuming overflow
582        /// cannot occur.
583        ///
584        /// Calling `x.unchecked_add(y)` is semantically equivalent to calling
585        /// `x.`[`checked_add`]`(y).`[`unwrap_unchecked`]`()`.
586        ///
587        /// If you're just trying to avoid the panic in debug mode, then **do not**
588        /// use this.  Instead, you're looking for [`wrapping_add`].
589        ///
590        /// # Safety
591        ///
592        /// This results in undefined behavior when
593        #[doc = concat!("`self + rhs > ", stringify!($SelfT), "::MAX` or `self + rhs < ", stringify!($SelfT), "::MIN`,")]
594        /// i.e. when [`checked_add`] would return `None`.
595        ///
596        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
597        #[doc = concat!("[`checked_add`]: ", stringify!($SelfT), "::checked_add")]
598        #[doc = concat!("[`wrapping_add`]: ", stringify!($SelfT), "::wrapping_add")]
599        #[stable(feature = "unchecked_math", since = "1.79.0")]
600        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
601        #[must_use = "this returns the result of the operation, \
602                      without modifying the original"]
603        #[inline(always)]
604        #[track_caller]
605        #[cfg(not(feature = "ferrocene_certified"))]
606        pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
607            assert_unsafe_precondition!(
608                check_language_ub,
609                concat!(stringify!($SelfT), "::unchecked_add cannot overflow"),
610                (
611                    lhs: $SelfT = self,
612                    rhs: $SelfT = rhs,
613                ) => !lhs.overflowing_add(rhs).1,
614            );
615
616            // SAFETY: this is guaranteed to be safe by the caller.
617            unsafe {
618                intrinsics::unchecked_add(self, rhs)
619            }
620        }
621
622        /// Checked addition with a signed integer. Computes `self + rhs`,
623        /// returning `None` if overflow occurred.
624        ///
625        /// # Examples
626        ///
627        /// ```
628        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(2), Some(3));")]
629        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(-2), None);")]
630        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_signed(3), None);")]
631        /// ```
632        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
633        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
634        #[must_use = "this returns the result of the operation, \
635                      without modifying the original"]
636        #[inline]
637        #[cfg(not(feature = "ferrocene_certified"))]
638        pub const fn checked_add_signed(self, rhs: $SignedT) -> Option<Self> {
639            let (a, b) = self.overflowing_add_signed(rhs);
640            if intrinsics::unlikely(b) { None } else { Some(a) }
641        }
642
643        /// Strict addition with a signed integer. Computes `self + rhs`,
644        /// panicking if overflow occurred.
645        ///
646        /// # Panics
647        ///
648        /// ## Overflow behavior
649        ///
650        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
651        ///
652        /// # Examples
653        ///
654        /// ```
655        /// #![feature(strict_overflow_ops)]
656        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_add_signed(2), 3);")]
657        /// ```
658        ///
659        /// The following panic because of overflow:
660        ///
661        /// ```should_panic
662        /// #![feature(strict_overflow_ops)]
663        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_add_signed(-2);")]
664        /// ```
665        ///
666        /// ```should_panic
667        /// #![feature(strict_overflow_ops)]
668        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add_signed(3);")]
669        /// ```
670        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
671        #[must_use = "this returns the result of the operation, \
672                      without modifying the original"]
673        #[inline]
674        #[track_caller]
675        #[cfg(not(feature = "ferrocene_certified"))]
676        pub const fn strict_add_signed(self, rhs: $SignedT) -> Self {
677            let (a, b) = self.overflowing_add_signed(rhs);
678            if b { overflow_panic::add() } else { a }
679        }
680
681        /// Checked integer subtraction. Computes `self - rhs`, returning
682        /// `None` if overflow occurred.
683        ///
684        /// # Examples
685        ///
686        /// ```
687        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub(1), Some(0));")]
688        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".checked_sub(1), None);")]
689        /// ```
690        #[stable(feature = "rust1", since = "1.0.0")]
691        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
692        #[must_use = "this returns the result of the operation, \
693                      without modifying the original"]
694        #[inline]
695        #[cfg(not(feature = "ferrocene_certified"))]
696        pub const fn checked_sub(self, rhs: Self) -> Option<Self> {
697            // Per PR#103299, there's no advantage to the `overflowing` intrinsic
698            // for *unsigned* subtraction and we just emit the manual check anyway.
699            // Thus, rather than using `overflowing_sub` that produces a wrapping
700            // subtraction, check it ourself so we can use an unchecked one.
701
702            if self < rhs {
703                None
704            } else {
705                // SAFETY: just checked this can't overflow
706                Some(unsafe { intrinsics::unchecked_sub(self, rhs) })
707            }
708        }
709
710        /// Strict integer subtraction. Computes `self - rhs`, panicking if
711        /// overflow occurred.
712        ///
713        /// # Panics
714        ///
715        /// ## Overflow behavior
716        ///
717        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
718        ///
719        /// # Examples
720        ///
721        /// ```
722        /// #![feature(strict_overflow_ops)]
723        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_sub(1), 0);")]
724        /// ```
725        ///
726        /// The following panics because of overflow:
727        ///
728        /// ```should_panic
729        /// #![feature(strict_overflow_ops)]
730        #[doc = concat!("let _ = 0", stringify!($SelfT), ".strict_sub(1);")]
731        /// ```
732        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
733        #[must_use = "this returns the result of the operation, \
734                      without modifying the original"]
735        #[inline]
736        #[track_caller]
737        #[cfg(not(feature = "ferrocene_certified"))]
738        pub const fn strict_sub(self, rhs: Self) -> Self {
739            let (a, b) = self.overflowing_sub(rhs);
740            if b { overflow_panic::sub() } else { a }
741        }
742
743        /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow
744        /// cannot occur.
745        ///
746        /// Calling `x.unchecked_sub(y)` is semantically equivalent to calling
747        /// `x.`[`checked_sub`]`(y).`[`unwrap_unchecked`]`()`.
748        ///
749        /// If you're just trying to avoid the panic in debug mode, then **do not**
750        /// use this.  Instead, you're looking for [`wrapping_sub`].
751        ///
752        /// If you find yourself writing code like this:
753        ///
754        /// ```
755        /// # let foo = 30_u32;
756        /// # let bar = 20;
757        /// if foo >= bar {
758        ///     // SAFETY: just checked it will not overflow
759        ///     let diff = unsafe { foo.unchecked_sub(bar) };
760        ///     // ... use diff ...
761        /// }
762        /// ```
763        ///
764        /// Consider changing it to
765        ///
766        /// ```
767        /// # let foo = 30_u32;
768        /// # let bar = 20;
769        /// if let Some(diff) = foo.checked_sub(bar) {
770        ///     // ... use diff ...
771        /// }
772        /// ```
773        ///
774        /// As that does exactly the same thing -- including telling the optimizer
775        /// that the subtraction cannot overflow -- but avoids needing `unsafe`.
776        ///
777        /// # Safety
778        ///
779        /// This results in undefined behavior when
780        #[doc = concat!("`self - rhs > ", stringify!($SelfT), "::MAX` or `self - rhs < ", stringify!($SelfT), "::MIN`,")]
781        /// i.e. when [`checked_sub`] would return `None`.
782        ///
783        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
784        #[doc = concat!("[`checked_sub`]: ", stringify!($SelfT), "::checked_sub")]
785        #[doc = concat!("[`wrapping_sub`]: ", stringify!($SelfT), "::wrapping_sub")]
786        #[stable(feature = "unchecked_math", since = "1.79.0")]
787        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
788        #[must_use = "this returns the result of the operation, \
789                      without modifying the original"]
790        #[inline(always)]
791        #[track_caller]
792        #[cfg(not(feature = "ferrocene_certified"))]
793        pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
794            assert_unsafe_precondition!(
795                check_language_ub,
796                concat!(stringify!($SelfT), "::unchecked_sub cannot overflow"),
797                (
798                    lhs: $SelfT = self,
799                    rhs: $SelfT = rhs,
800                ) => !lhs.overflowing_sub(rhs).1,
801            );
802
803            // SAFETY: this is guaranteed to be safe by the caller.
804            unsafe {
805                intrinsics::unchecked_sub(self, rhs)
806            }
807        }
808
809        /// Checked subtraction with a signed integer. Computes `self - rhs`,
810        /// returning `None` if overflow occurred.
811        ///
812        /// # Examples
813        ///
814        /// ```
815        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_signed(2), None);")]
816        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_signed(-2), Some(3));")]
817        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_sub_signed(-4), None);")]
818        /// ```
819        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
820        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
821        #[must_use = "this returns the result of the operation, \
822                      without modifying the original"]
823        #[inline]
824        #[cfg(not(feature = "ferrocene_certified"))]
825        pub const fn checked_sub_signed(self, rhs: $SignedT) -> Option<Self> {
826            let (res, overflow) = self.overflowing_sub_signed(rhs);
827
828            if !overflow {
829                Some(res)
830            } else {
831                None
832            }
833        }
834
835        /// Strict subtraction with a signed integer. Computes `self - rhs`,
836        /// panicking if overflow occurred.
837        ///
838        /// # Panics
839        ///
840        /// ## Overflow behavior
841        ///
842        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
843        ///
844        /// # Examples
845        ///
846        /// ```
847        /// #![feature(strict_overflow_ops)]
848        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".strict_sub_signed(2), 1);")]
849        /// ```
850        ///
851        /// The following panic because of overflow:
852        ///
853        /// ```should_panic
854        /// #![feature(strict_overflow_ops)]
855        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_sub_signed(2);")]
856        /// ```
857        ///
858        /// ```should_panic
859        /// #![feature(strict_overflow_ops)]
860        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX).strict_sub_signed(-1);")]
861        /// ```
862        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
863        #[must_use = "this returns the result of the operation, \
864                      without modifying the original"]
865        #[inline]
866        #[track_caller]
867        #[cfg(not(feature = "ferrocene_certified"))]
868        pub const fn strict_sub_signed(self, rhs: $SignedT) -> Self {
869            let (a, b) = self.overflowing_sub_signed(rhs);
870            if b { overflow_panic::sub() } else { a }
871        }
872
873        #[doc = concat!(
874            "Checked integer subtraction. Computes `self - rhs` and checks if the result fits into an [`",
875            stringify!($SignedT), "`], returning `None` if overflow occurred."
876        )]
877        ///
878        /// # Examples
879        ///
880        /// ```
881        /// #![feature(unsigned_signed_diff)]
882        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_signed_diff(2), Some(8));")]
883        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_signed_diff(10), Some(-8));")]
884        #[doc = concat!(
885            "assert_eq!(",
886            stringify!($SelfT),
887            "::MAX.checked_signed_diff(",
888            stringify!($SignedT),
889            "::MAX as ",
890            stringify!($SelfT),
891            "), None);"
892        )]
893        #[doc = concat!(
894            "assert_eq!((",
895            stringify!($SignedT),
896            "::MAX as ",
897            stringify!($SelfT),
898            ").checked_signed_diff(",
899            stringify!($SelfT),
900            "::MAX), Some(",
901            stringify!($SignedT),
902            "::MIN));"
903        )]
904        #[doc = concat!(
905            "assert_eq!((",
906            stringify!($SignedT),
907            "::MAX as ",
908            stringify!($SelfT),
909            " + 1).checked_signed_diff(0), None);"
910        )]
911        #[doc = concat!(
912            "assert_eq!(",
913            stringify!($SelfT),
914            "::MAX.checked_signed_diff(",
915            stringify!($SelfT),
916            "::MAX), Some(0));"
917        )]
918        /// ```
919        #[unstable(feature = "unsigned_signed_diff", issue = "126041")]
920        #[inline]
921        #[cfg(not(feature = "ferrocene_certified"))]
922        pub const fn checked_signed_diff(self, rhs: Self) -> Option<$SignedT> {
923            let res = self.wrapping_sub(rhs) as $SignedT;
924            let overflow = (self >= rhs) == (res < 0);
925
926            if !overflow {
927                Some(res)
928            } else {
929                None
930            }
931        }
932
933        /// Checked integer multiplication. Computes `self * rhs`, returning
934        /// `None` if overflow occurred.
935        ///
936        /// # Examples
937        ///
938        /// ```
939        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_mul(1), Some(5));")]
940        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);")]
941        /// ```
942        #[stable(feature = "rust1", since = "1.0.0")]
943        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
944        #[must_use = "this returns the result of the operation, \
945                      without modifying the original"]
946        #[inline]
947        #[cfg(not(feature = "ferrocene_certified"))]
948        pub const fn checked_mul(self, rhs: Self) -> Option<Self> {
949            let (a, b) = self.overflowing_mul(rhs);
950            if intrinsics::unlikely(b) { None } else { Some(a) }
951        }
952
953        /// Strict integer multiplication. Computes `self * rhs`, panicking if
954        /// overflow occurred.
955        ///
956        /// # Panics
957        ///
958        /// ## Overflow behavior
959        ///
960        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
961        ///
962        /// # Examples
963        ///
964        /// ```
965        /// #![feature(strict_overflow_ops)]
966        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_mul(1), 5);")]
967        /// ```
968        ///
969        /// The following panics because of overflow:
970        ///
971        /// ``` should_panic
972        /// #![feature(strict_overflow_ops)]
973        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_mul(2);")]
974        /// ```
975        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
976        #[must_use = "this returns the result of the operation, \
977                      without modifying the original"]
978        #[inline]
979        #[track_caller]
980        #[cfg(not(feature = "ferrocene_certified"))]
981        pub const fn strict_mul(self, rhs: Self) -> Self {
982            let (a, b) = self.overflowing_mul(rhs);
983            if b { overflow_panic::mul() } else { a }
984        }
985
986        /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow
987        /// cannot occur.
988        ///
989        /// Calling `x.unchecked_mul(y)` is semantically equivalent to calling
990        /// `x.`[`checked_mul`]`(y).`[`unwrap_unchecked`]`()`.
991        ///
992        /// If you're just trying to avoid the panic in debug mode, then **do not**
993        /// use this.  Instead, you're looking for [`wrapping_mul`].
994        ///
995        /// # Safety
996        ///
997        /// This results in undefined behavior when
998        #[doc = concat!("`self * rhs > ", stringify!($SelfT), "::MAX` or `self * rhs < ", stringify!($SelfT), "::MIN`,")]
999        /// i.e. when [`checked_mul`] would return `None`.
1000        ///
1001        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
1002        #[doc = concat!("[`checked_mul`]: ", stringify!($SelfT), "::checked_mul")]
1003        #[doc = concat!("[`wrapping_mul`]: ", stringify!($SelfT), "::wrapping_mul")]
1004        #[stable(feature = "unchecked_math", since = "1.79.0")]
1005        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
1006        #[must_use = "this returns the result of the operation, \
1007                      without modifying the original"]
1008        #[inline(always)]
1009        #[track_caller]
1010        #[cfg(not(feature = "ferrocene_certified"))]
1011        pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
1012            assert_unsafe_precondition!(
1013                check_language_ub,
1014                concat!(stringify!($SelfT), "::unchecked_mul cannot overflow"),
1015                (
1016                    lhs: $SelfT = self,
1017                    rhs: $SelfT = rhs,
1018                ) => !lhs.overflowing_mul(rhs).1,
1019            );
1020
1021            // SAFETY: this is guaranteed to be safe by the caller.
1022            unsafe {
1023                intrinsics::unchecked_mul(self, rhs)
1024            }
1025        }
1026
1027        /// Checked integer division. Computes `self / rhs`, returning `None`
1028        /// if `rhs == 0`.
1029        ///
1030        /// # Examples
1031        ///
1032        /// ```
1033        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".checked_div(2), Some(64));")]
1034        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_div(0), None);")]
1035        /// ```
1036        #[stable(feature = "rust1", since = "1.0.0")]
1037        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
1038        #[must_use = "this returns the result of the operation, \
1039                      without modifying the original"]
1040        #[inline]
1041        #[cfg(not(feature = "ferrocene_certified"))]
1042        pub const fn checked_div(self, rhs: Self) -> Option<Self> {
1043            if intrinsics::unlikely(rhs == 0) {
1044                None
1045            } else {
1046                // SAFETY: div by zero has been checked above and unsigned types have no other
1047                // failure modes for division
1048                Some(unsafe { intrinsics::unchecked_div(self, rhs) })
1049            }
1050        }
1051
1052        /// Strict integer division. Computes `self / rhs`.
1053        ///
1054        /// Strict division on unsigned types is just normal division. There's no
1055        /// way overflow could ever happen. This function exists so that all
1056        /// operations are accounted for in the strict operations.
1057        ///
1058        /// # Panics
1059        ///
1060        /// This function will panic if `rhs` is zero.
1061        ///
1062        /// # Examples
1063        ///
1064        /// ```
1065        /// #![feature(strict_overflow_ops)]
1066        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_div(10), 10);")]
1067        /// ```
1068        ///
1069        /// The following panics because of division by zero:
1070        ///
1071        /// ```should_panic
1072        /// #![feature(strict_overflow_ops)]
1073        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div(0);")]
1074        /// ```
1075        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1076        #[must_use = "this returns the result of the operation, \
1077                      without modifying the original"]
1078        #[inline(always)]
1079        #[track_caller]
1080        #[cfg(not(feature = "ferrocene_certified"))]
1081        pub const fn strict_div(self, rhs: Self) -> Self {
1082            self / rhs
1083        }
1084
1085        /// Checked Euclidean division. Computes `self.div_euclid(rhs)`, returning `None`
1086        /// if `rhs == 0`.
1087        ///
1088        /// # Examples
1089        ///
1090        /// ```
1091        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".checked_div_euclid(2), Some(64));")]
1092        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_div_euclid(0), None);")]
1093        /// ```
1094        #[stable(feature = "euclidean_division", since = "1.38.0")]
1095        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1096        #[must_use = "this returns the result of the operation, \
1097                      without modifying the original"]
1098        #[inline]
1099        #[cfg(not(feature = "ferrocene_certified"))]
1100        pub const fn checked_div_euclid(self, rhs: Self) -> Option<Self> {
1101            if intrinsics::unlikely(rhs == 0) {
1102                None
1103            } else {
1104                Some(self.div_euclid(rhs))
1105            }
1106        }
1107
1108        /// Strict Euclidean division. Computes `self.div_euclid(rhs)`.
1109        ///
1110        /// Strict division on unsigned types is just normal division. There's no
1111        /// way overflow could ever happen. This function exists so that all
1112        /// operations are accounted for in the strict operations. Since, for the
1113        /// positive integers, all common definitions of division are equal, this
1114        /// is exactly equal to `self.strict_div(rhs)`.
1115        ///
1116        /// # Panics
1117        ///
1118        /// This function will panic if `rhs` is zero.
1119        ///
1120        /// # Examples
1121        ///
1122        /// ```
1123        /// #![feature(strict_overflow_ops)]
1124        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_div_euclid(10), 10);")]
1125        /// ```
1126        /// The following panics because of division by zero:
1127        ///
1128        /// ```should_panic
1129        /// #![feature(strict_overflow_ops)]
1130        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div_euclid(0);")]
1131        /// ```
1132        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1133        #[must_use = "this returns the result of the operation, \
1134                      without modifying the original"]
1135        #[inline(always)]
1136        #[track_caller]
1137        #[cfg(not(feature = "ferrocene_certified"))]
1138        pub const fn strict_div_euclid(self, rhs: Self) -> Self {
1139            self / rhs
1140        }
1141
1142        /// Checked integer division without remainder. Computes `self / rhs`.
1143        ///
1144        /// # Panics
1145        ///
1146        /// This function will panic  if `rhs == 0` or `self % rhs != 0`.
1147        ///
1148        /// # Examples
1149        ///
1150        /// ```
1151        /// #![feature(exact_div)]
1152        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(2), 32);")]
1153        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(32), 2);")]
1154        /// ```
1155        ///
1156        /// ```should_panic
1157        /// #![feature(exact_div)]
1158        #[doc = concat!("let _ = 65", stringify!($SelfT), ".exact_div(2);")]
1159        /// ```
1160        #[unstable(
1161            feature = "exact_div",
1162            issue = "139911",
1163        )]
1164        #[must_use = "this returns the result of the operation, \
1165                      without modifying the original"]
1166        #[inline]
1167        #[cfg(not(feature = "ferrocene_certified"))]
1168        pub const fn checked_exact_div(self, rhs: Self) -> Option<Self> {
1169            if intrinsics::unlikely(rhs == 0) {
1170                None
1171            } else {
1172                // SAFETY: division by zero is checked above
1173                unsafe {
1174                    if intrinsics::unlikely(intrinsics::unchecked_rem(self, rhs) != 0) {
1175                        None
1176                    } else {
1177                        Some(intrinsics::exact_div(self, rhs))
1178                    }
1179                }
1180            }
1181        }
1182
1183        /// Checked integer division without remainder. Computes `self / rhs`.
1184        ///
1185        /// # Panics
1186        ///
1187        /// This function will panic  if `rhs == 0` or `self % rhs != 0`.
1188        ///
1189        /// # Examples
1190        ///
1191        /// ```
1192        /// #![feature(exact_div)]
1193        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(2), 32);")]
1194        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(32), 2);")]
1195        /// ```
1196        ///
1197        /// ```should_panic
1198        /// #![feature(exact_div)]
1199        #[doc = concat!("let _ = 65", stringify!($SelfT), ".exact_div(2);")]
1200        /// ```
1201        #[unstable(
1202            feature = "exact_div",
1203            issue = "139911",
1204        )]
1205        #[must_use = "this returns the result of the operation, \
1206                      without modifying the original"]
1207        #[inline]
1208        #[cfg(not(feature = "ferrocene_certified"))]
1209        pub const fn exact_div(self, rhs: Self) -> Self {
1210            match self.checked_exact_div(rhs) {
1211                Some(x) => x,
1212                None => panic!("Failed to divide without remainder"),
1213            }
1214        }
1215
1216        /// Unchecked integer division without remainder. Computes `self / rhs`.
1217        ///
1218        /// # Safety
1219        ///
1220        /// This results in undefined behavior when `rhs == 0` or `self % rhs != 0`,
1221        /// i.e. when [`checked_exact_div`](Self::checked_exact_div) would return `None`.
1222        #[unstable(
1223            feature = "exact_div",
1224            issue = "139911",
1225        )]
1226        #[must_use = "this returns the result of the operation, \
1227                      without modifying the original"]
1228        #[inline]
1229        #[cfg(not(feature = "ferrocene_certified"))]
1230        pub const unsafe fn unchecked_exact_div(self, rhs: Self) -> Self {
1231            assert_unsafe_precondition!(
1232                check_language_ub,
1233                concat!(stringify!($SelfT), "::unchecked_exact_div divide by zero or leave a remainder"),
1234                (
1235                    lhs: $SelfT = self,
1236                    rhs: $SelfT = rhs,
1237                ) => rhs > 0 && lhs % rhs == 0,
1238            );
1239            // SAFETY: Same precondition
1240            unsafe { intrinsics::exact_div(self, rhs) }
1241        }
1242
1243        /// Checked integer remainder. Computes `self % rhs`, returning `None`
1244        /// if `rhs == 0`.
1245        ///
1246        /// # Examples
1247        ///
1248        /// ```
1249        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(2), Some(1));")]
1250        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(0), None);")]
1251        /// ```
1252        #[stable(feature = "wrapping", since = "1.7.0")]
1253        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
1254        #[must_use = "this returns the result of the operation, \
1255                      without modifying the original"]
1256        #[inline]
1257        #[cfg(not(feature = "ferrocene_certified"))]
1258        pub const fn checked_rem(self, rhs: Self) -> Option<Self> {
1259            if intrinsics::unlikely(rhs == 0) {
1260                None
1261            } else {
1262                // SAFETY: div by zero has been checked above and unsigned types have no other
1263                // failure modes for division
1264                Some(unsafe { intrinsics::unchecked_rem(self, rhs) })
1265            }
1266        }
1267
1268        /// Strict integer remainder. Computes `self % rhs`.
1269        ///
1270        /// Strict remainder calculation on unsigned types is just the regular
1271        /// remainder calculation. There's no way overflow could ever happen.
1272        /// This function exists so that all operations are accounted for in the
1273        /// strict operations.
1274        ///
1275        /// # Panics
1276        ///
1277        /// This function will panic if `rhs` is zero.
1278        ///
1279        /// # Examples
1280        ///
1281        /// ```
1282        /// #![feature(strict_overflow_ops)]
1283        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_rem(10), 0);")]
1284        /// ```
1285        ///
1286        /// The following panics because of division by zero:
1287        ///
1288        /// ```should_panic
1289        /// #![feature(strict_overflow_ops)]
1290        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem(0);")]
1291        /// ```
1292        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1293        #[must_use = "this returns the result of the operation, \
1294                      without modifying the original"]
1295        #[inline(always)]
1296        #[track_caller]
1297        #[cfg(not(feature = "ferrocene_certified"))]
1298        pub const fn strict_rem(self, rhs: Self) -> Self {
1299            self % rhs
1300        }
1301
1302        /// Checked Euclidean modulo. Computes `self.rem_euclid(rhs)`, returning `None`
1303        /// if `rhs == 0`.
1304        ///
1305        /// # Examples
1306        ///
1307        /// ```
1308        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(2), Some(1));")]
1309        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(0), None);")]
1310        /// ```
1311        #[stable(feature = "euclidean_division", since = "1.38.0")]
1312        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1313        #[must_use = "this returns the result of the operation, \
1314                      without modifying the original"]
1315        #[inline]
1316        #[cfg(not(feature = "ferrocene_certified"))]
1317        pub const fn checked_rem_euclid(self, rhs: Self) -> Option<Self> {
1318            if intrinsics::unlikely(rhs == 0) {
1319                None
1320            } else {
1321                Some(self.rem_euclid(rhs))
1322            }
1323        }
1324
1325        /// Strict Euclidean modulo. Computes `self.rem_euclid(rhs)`.
1326        ///
1327        /// Strict modulo calculation on unsigned types is just the regular
1328        /// remainder calculation. There's no way overflow could ever happen.
1329        /// This function exists so that all operations are accounted for in the
1330        /// strict operations. Since, for the positive integers, all common
1331        /// definitions of division are equal, this is exactly equal to
1332        /// `self.strict_rem(rhs)`.
1333        ///
1334        /// # Panics
1335        ///
1336        /// This function will panic if `rhs` is zero.
1337        ///
1338        /// # Examples
1339        ///
1340        /// ```
1341        /// #![feature(strict_overflow_ops)]
1342        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".strict_rem_euclid(10), 0);")]
1343        /// ```
1344        ///
1345        /// The following panics because of division by zero:
1346        ///
1347        /// ```should_panic
1348        /// #![feature(strict_overflow_ops)]
1349        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem_euclid(0);")]
1350        /// ```
1351        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1352        #[must_use = "this returns the result of the operation, \
1353                      without modifying the original"]
1354        #[inline(always)]
1355        #[track_caller]
1356        #[cfg(not(feature = "ferrocene_certified"))]
1357        pub const fn strict_rem_euclid(self, rhs: Self) -> Self {
1358            self % rhs
1359        }
1360
1361        /// Same value as `self | other`, but UB if any bit position is set in both inputs.
1362        ///
1363        /// This is a situational micro-optimization for places where you'd rather
1364        /// use addition on some platforms and bitwise or on other platforms, based
1365        /// on exactly which instructions combine better with whatever else you're
1366        /// doing.  Note that there's no reason to bother using this for places
1367        /// where it's clear from the operations involved that they can't overlap.
1368        /// For example, if you're combining `u16`s into a `u32` with
1369        /// `((a as u32) << 16) | (b as u32)`, that's fine, as the backend will
1370        /// know those sides of the `|` are disjoint without needing help.
1371        ///
1372        /// # Examples
1373        ///
1374        /// ```
1375        /// #![feature(disjoint_bitor)]
1376        ///
1377        /// // SAFETY: `1` and `4` have no bits in common.
1378        /// unsafe {
1379        #[doc = concat!("    assert_eq!(1_", stringify!($SelfT), ".unchecked_disjoint_bitor(4), 5);")]
1380        /// }
1381        /// ```
1382        ///
1383        /// # Safety
1384        ///
1385        /// Requires that `(self & other) == 0`, otherwise it's immediate UB.
1386        ///
1387        /// Equivalently, requires that `(self | other) == (self + other)`.
1388        #[unstable(feature = "disjoint_bitor", issue = "135758")]
1389        #[rustc_const_unstable(feature = "disjoint_bitor", issue = "135758")]
1390        #[inline]
1391        #[cfg(not(feature = "ferrocene_certified"))]
1392        pub const unsafe fn unchecked_disjoint_bitor(self, other: Self) -> Self {
1393            assert_unsafe_precondition!(
1394                check_language_ub,
1395                concat!(stringify!($SelfT), "::unchecked_disjoint_bitor cannot have overlapping bits"),
1396                (
1397                    lhs: $SelfT = self,
1398                    rhs: $SelfT = other,
1399                ) => (lhs & rhs) == 0,
1400            );
1401
1402            // SAFETY: Same precondition
1403            unsafe { intrinsics::disjoint_bitor(self, other) }
1404        }
1405
1406        /// Returns the logarithm of the number with respect to an arbitrary base,
1407        /// rounded down.
1408        ///
1409        /// This method might not be optimized owing to implementation details;
1410        /// `ilog2` can produce results more efficiently for base 2, and `ilog10`
1411        /// can produce results more efficiently for base 10.
1412        ///
1413        /// # Panics
1414        ///
1415        /// This function will panic if `self` is zero, or if `base` is less than 2.
1416        ///
1417        /// # Examples
1418        ///
1419        /// ```
1420        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")]
1421        /// ```
1422        #[stable(feature = "int_log", since = "1.67.0")]
1423        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1424        #[must_use = "this returns the result of the operation, \
1425                      without modifying the original"]
1426        #[inline]
1427        #[track_caller]
1428        #[cfg(not(feature = "ferrocene_certified"))]
1429        pub const fn ilog(self, base: Self) -> u32 {
1430            assert!(base >= 2, "base of integer logarithm must be at least 2");
1431            if let Some(log) = self.checked_ilog(base) {
1432                log
1433            } else {
1434                int_log10::panic_for_nonpositive_argument()
1435            }
1436        }
1437
1438        /// Returns the base 2 logarithm of the number, rounded down.
1439        ///
1440        /// # Panics
1441        ///
1442        /// This function will panic if `self` is zero.
1443        ///
1444        /// # Examples
1445        ///
1446        /// ```
1447        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")]
1448        /// ```
1449        #[stable(feature = "int_log", since = "1.67.0")]
1450        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1451        #[must_use = "this returns the result of the operation, \
1452                      without modifying the original"]
1453        #[inline]
1454        #[track_caller]
1455        #[cfg(not(feature = "ferrocene_certified"))]
1456        pub const fn ilog2(self) -> u32 {
1457            if let Some(log) = self.checked_ilog2() {
1458                log
1459            } else {
1460                int_log10::panic_for_nonpositive_argument()
1461            }
1462        }
1463
1464        /// Returns the base 10 logarithm of the number, rounded down.
1465        ///
1466        /// # Panics
1467        ///
1468        /// This function will panic if `self` is zero.
1469        ///
1470        /// # Example
1471        ///
1472        /// ```
1473        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")]
1474        /// ```
1475        #[stable(feature = "int_log", since = "1.67.0")]
1476        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1477        #[must_use = "this returns the result of the operation, \
1478                      without modifying the original"]
1479        #[inline]
1480        #[track_caller]
1481        #[cfg(not(feature = "ferrocene_certified"))]
1482        pub const fn ilog10(self) -> u32 {
1483            if let Some(log) = self.checked_ilog10() {
1484                log
1485            } else {
1486                int_log10::panic_for_nonpositive_argument()
1487            }
1488        }
1489
1490        /// Returns the logarithm of the number with respect to an arbitrary base,
1491        /// rounded down.
1492        ///
1493        /// Returns `None` if the number is zero, or if the base is not at least 2.
1494        ///
1495        /// This method might not be optimized owing to implementation details;
1496        /// `checked_ilog2` can produce results more efficiently for base 2, and
1497        /// `checked_ilog10` can produce results more efficiently for base 10.
1498        ///
1499        /// # Examples
1500        ///
1501        /// ```
1502        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")]
1503        /// ```
1504        #[stable(feature = "int_log", since = "1.67.0")]
1505        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1506        #[must_use = "this returns the result of the operation, \
1507                      without modifying the original"]
1508        #[inline]
1509        #[cfg(not(feature = "ferrocene_certified"))]
1510        pub const fn checked_ilog(self, base: Self) -> Option<u32> {
1511            if self <= 0 || base <= 1 {
1512                None
1513            } else if self < base {
1514                Some(0)
1515            } else {
1516                // Since base >= self, n >= 1
1517                let mut n = 1;
1518                let mut r = base;
1519
1520                // Optimization for 128 bit wide integers.
1521                if Self::BITS == 128 {
1522                    // The following is a correct lower bound for ⌊log(base,self)⌋ because
1523                    //
1524                    // log(base,self) = log(2,self) / log(2,base)
1525                    //                ≥ ⌊log(2,self)⌋ / (⌊log(2,base)⌋ + 1)
1526                    //
1527                    // hence
1528                    //
1529                    // ⌊log(base,self)⌋ ≥ ⌊ ⌊log(2,self)⌋ / (⌊log(2,base)⌋ + 1) ⌋ .
1530                    n = self.ilog2() / (base.ilog2() + 1);
1531                    r = base.pow(n);
1532                }
1533
1534                while r <= self / base {
1535                    n += 1;
1536                    r *= base;
1537                }
1538                Some(n)
1539            }
1540        }
1541
1542        /// Returns the base 2 logarithm of the number, rounded down.
1543        ///
1544        /// Returns `None` if the number is zero.
1545        ///
1546        /// # Examples
1547        ///
1548        /// ```
1549        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")]
1550        /// ```
1551        #[stable(feature = "int_log", since = "1.67.0")]
1552        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1553        #[must_use = "this returns the result of the operation, \
1554                      without modifying the original"]
1555        #[inline]
1556        #[cfg(not(feature = "ferrocene_certified"))]
1557        pub const fn checked_ilog2(self) -> Option<u32> {
1558            match NonZero::new(self) {
1559                Some(x) => Some(x.ilog2()),
1560                None => None,
1561            }
1562        }
1563
1564        /// Returns the base 10 logarithm of the number, rounded down.
1565        ///
1566        /// Returns `None` if the number is zero.
1567        ///
1568        /// # Examples
1569        ///
1570        /// ```
1571        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")]
1572        /// ```
1573        #[stable(feature = "int_log", since = "1.67.0")]
1574        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
1575        #[must_use = "this returns the result of the operation, \
1576                      without modifying the original"]
1577        #[inline]
1578        #[cfg(not(feature = "ferrocene_certified"))]
1579        pub const fn checked_ilog10(self) -> Option<u32> {
1580            match NonZero::new(self) {
1581                Some(x) => Some(x.ilog10()),
1582                None => None,
1583            }
1584        }
1585
1586        /// Checked negation. Computes `-self`, returning `None` unless `self ==
1587        /// 0`.
1588        ///
1589        /// Note that negating any positive integer will overflow.
1590        ///
1591        /// # Examples
1592        ///
1593        /// ```
1594        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".checked_neg(), Some(0));")]
1595        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_neg(), None);")]
1596        /// ```
1597        #[stable(feature = "wrapping", since = "1.7.0")]
1598        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1599        #[must_use = "this returns the result of the operation, \
1600                      without modifying the original"]
1601        #[inline]
1602        #[cfg(not(feature = "ferrocene_certified"))]
1603        pub const fn checked_neg(self) -> Option<Self> {
1604            let (a, b) = self.overflowing_neg();
1605            if intrinsics::unlikely(b) { None } else { Some(a) }
1606        }
1607
1608        /// Strict negation. Computes `-self`, panicking unless `self ==
1609        /// 0`.
1610        ///
1611        /// Note that negating any positive integer will overflow.
1612        ///
1613        /// # Panics
1614        ///
1615        /// ## Overflow behavior
1616        ///
1617        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1618        ///
1619        /// # Examples
1620        ///
1621        /// ```
1622        /// #![feature(strict_overflow_ops)]
1623        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".strict_neg(), 0);")]
1624        /// ```
1625        ///
1626        /// The following panics because of overflow:
1627        ///
1628        /// ```should_panic
1629        /// #![feature(strict_overflow_ops)]
1630        #[doc = concat!("let _ = 1", stringify!($SelfT), ".strict_neg();")]
1631        ///
1632        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1633        #[must_use = "this returns the result of the operation, \
1634                      without modifying the original"]
1635        #[inline]
1636        #[track_caller]
1637        #[cfg(not(feature = "ferrocene_certified"))]
1638        pub const fn strict_neg(self) -> Self {
1639            let (a, b) = self.overflowing_neg();
1640            if b { overflow_panic::neg() } else { a }
1641        }
1642
1643        /// Checked shift left. Computes `self << rhs`, returning `None`
1644        /// if `rhs` is larger than or equal to the number of bits in `self`.
1645        ///
1646        /// # Examples
1647        ///
1648        /// ```
1649        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(4), Some(0x10));")]
1650        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(129), None);")]
1651        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(", stringify!($BITS_MINUS_ONE), "), Some(0));")]
1652        /// ```
1653        #[stable(feature = "wrapping", since = "1.7.0")]
1654        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1655        #[must_use = "this returns the result of the operation, \
1656                      without modifying the original"]
1657        #[inline]
1658        #[cfg(not(feature = "ferrocene_certified"))]
1659        pub const fn checked_shl(self, rhs: u32) -> Option<Self> {
1660            // Not using overflowing_shl as that's a wrapping shift
1661            if rhs < Self::BITS {
1662                // SAFETY: just checked the RHS is in-range
1663                Some(unsafe { self.unchecked_shl(rhs) })
1664            } else {
1665                None
1666            }
1667        }
1668
1669        /// Strict shift left. Computes `self << rhs`, panicking if `rhs` is larger
1670        /// than or equal to the number of bits in `self`.
1671        ///
1672        /// # Panics
1673        ///
1674        /// ## Overflow behavior
1675        ///
1676        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1677        ///
1678        /// # Examples
1679        ///
1680        /// ```
1681        /// #![feature(strict_overflow_ops)]
1682        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".strict_shl(4), 0x10);")]
1683        /// ```
1684        ///
1685        /// The following panics because of overflow:
1686        ///
1687        /// ```should_panic
1688        /// #![feature(strict_overflow_ops)]
1689        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shl(129);")]
1690        /// ```
1691        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1692        #[must_use = "this returns the result of the operation, \
1693                      without modifying the original"]
1694        #[inline]
1695        #[track_caller]
1696        #[cfg(not(feature = "ferrocene_certified"))]
1697        pub const fn strict_shl(self, rhs: u32) -> Self {
1698            let (a, b) = self.overflowing_shl(rhs);
1699            if b { overflow_panic::shl() } else { a }
1700        }
1701
1702        /// Unchecked shift left. Computes `self << rhs`, assuming that
1703        /// `rhs` is less than the number of bits in `self`.
1704        ///
1705        /// # Safety
1706        ///
1707        /// This results in undefined behavior if `rhs` is larger than
1708        /// or equal to the number of bits in `self`,
1709        /// i.e. when [`checked_shl`] would return `None`.
1710        ///
1711        #[doc = concat!("[`checked_shl`]: ", stringify!($SelfT), "::checked_shl")]
1712        #[unstable(
1713            feature = "unchecked_shifts",
1714            reason = "niche optimization path",
1715            issue = "85122",
1716        )]
1717        #[must_use = "this returns the result of the operation, \
1718                      without modifying the original"]
1719        #[inline(always)]
1720        #[track_caller]
1721        #[cfg(not(feature = "ferrocene_certified"))]
1722        pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
1723            assert_unsafe_precondition!(
1724                check_language_ub,
1725                concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"),
1726                (
1727                    rhs: u32 = rhs,
1728                ) => rhs < <$ActualT>::BITS,
1729            );
1730
1731            // SAFETY: this is guaranteed to be safe by the caller.
1732            unsafe {
1733                intrinsics::unchecked_shl(self, rhs)
1734            }
1735        }
1736
1737        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`.
1738        ///
1739        /// If `rhs` is larger or equal to the number of bits in `self`,
1740        /// the entire value is shifted out, and `0` is returned.
1741        ///
1742        /// # Examples
1743        ///
1744        /// ```
1745        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(4), 0x10);")]
1746        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(129), 0);")]
1747        /// ```
1748        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1749        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1750        #[must_use = "this returns the result of the operation, \
1751                      without modifying the original"]
1752        #[inline]
1753        #[cfg(not(feature = "ferrocene_certified"))]
1754        pub const fn unbounded_shl(self, rhs: u32) -> $SelfT{
1755            if rhs < Self::BITS {
1756                // SAFETY:
1757                // rhs is just checked to be in-range above
1758                unsafe { self.unchecked_shl(rhs) }
1759            } else {
1760                0
1761            }
1762        }
1763
1764        /// Checked shift right. Computes `self >> rhs`, returning `None`
1765        /// if `rhs` is larger than or equal to the number of bits in `self`.
1766        ///
1767        /// # Examples
1768        ///
1769        /// ```
1770        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(4), Some(0x1));")]
1771        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(129), None);")]
1772        /// ```
1773        #[stable(feature = "wrapping", since = "1.7.0")]
1774        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1775        #[must_use = "this returns the result of the operation, \
1776                      without modifying the original"]
1777        #[inline]
1778        #[cfg(not(feature = "ferrocene_certified"))]
1779        pub const fn checked_shr(self, rhs: u32) -> Option<Self> {
1780            // Not using overflowing_shr as that's a wrapping shift
1781            if rhs < Self::BITS {
1782                // SAFETY: just checked the RHS is in-range
1783                Some(unsafe { self.unchecked_shr(rhs) })
1784            } else {
1785                None
1786            }
1787        }
1788
1789        /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is
1790        /// larger than or equal to the number of bits in `self`.
1791        ///
1792        /// # Panics
1793        ///
1794        /// ## Overflow behavior
1795        ///
1796        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1797        ///
1798        /// # Examples
1799        ///
1800        /// ```
1801        /// #![feature(strict_overflow_ops)]
1802        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".strict_shr(4), 0x1);")]
1803        /// ```
1804        ///
1805        /// The following panics because of overflow:
1806        ///
1807        /// ```should_panic
1808        /// #![feature(strict_overflow_ops)]
1809        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shr(129);")]
1810        /// ```
1811        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1812        #[must_use = "this returns the result of the operation, \
1813                      without modifying the original"]
1814        #[inline]
1815        #[track_caller]
1816        #[cfg(not(feature = "ferrocene_certified"))]
1817        pub const fn strict_shr(self, rhs: u32) -> Self {
1818            let (a, b) = self.overflowing_shr(rhs);
1819            if b { overflow_panic::shr() } else { a }
1820        }
1821
1822        /// Unchecked shift right. Computes `self >> rhs`, assuming that
1823        /// `rhs` is less than the number of bits in `self`.
1824        ///
1825        /// # Safety
1826        ///
1827        /// This results in undefined behavior if `rhs` is larger than
1828        /// or equal to the number of bits in `self`,
1829        /// i.e. when [`checked_shr`] would return `None`.
1830        ///
1831        #[doc = concat!("[`checked_shr`]: ", stringify!($SelfT), "::checked_shr")]
1832        #[unstable(
1833            feature = "unchecked_shifts",
1834            reason = "niche optimization path",
1835            issue = "85122",
1836        )]
1837        #[must_use = "this returns the result of the operation, \
1838                      without modifying the original"]
1839        #[inline(always)]
1840        #[track_caller]
1841        #[cfg(not(feature = "ferrocene_certified"))]
1842        pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
1843            assert_unsafe_precondition!(
1844                check_language_ub,
1845                concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"),
1846                (
1847                    rhs: u32 = rhs,
1848                ) => rhs < <$ActualT>::BITS,
1849            );
1850
1851            // SAFETY: this is guaranteed to be safe by the caller.
1852            unsafe {
1853                intrinsics::unchecked_shr(self, rhs)
1854            }
1855        }
1856
1857        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`.
1858        ///
1859        /// If `rhs` is larger or equal to the number of bits in `self`,
1860        /// the entire value is shifted out, and `0` is returned.
1861        ///
1862        /// # Examples
1863        ///
1864        /// ```
1865        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(4), 0x1);")]
1866        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(129), 0);")]
1867        /// ```
1868        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1869        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1870        #[must_use = "this returns the result of the operation, \
1871                      without modifying the original"]
1872        #[inline]
1873        #[cfg(not(feature = "ferrocene_certified"))]
1874        pub const fn unbounded_shr(self, rhs: u32) -> $SelfT{
1875            if rhs < Self::BITS {
1876                // SAFETY:
1877                // rhs is just checked to be in-range above
1878                unsafe { self.unchecked_shr(rhs) }
1879            } else {
1880                0
1881            }
1882        }
1883
1884        /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if
1885        /// overflow occurred.
1886        ///
1887        /// # Examples
1888        ///
1889        /// ```
1890        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_pow(5), Some(32));")]
1891        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_pow(2), None);")]
1892        /// ```
1893        #[stable(feature = "no_panic_pow", since = "1.34.0")]
1894        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
1895        #[must_use = "this returns the result of the operation, \
1896                      without modifying the original"]
1897        #[inline]
1898        #[cfg(not(feature = "ferrocene_certified"))]
1899        pub const fn checked_pow(self, mut exp: u32) -> Option<Self> {
1900            if exp == 0 {
1901                return Some(1);
1902            }
1903            let mut base = self;
1904            let mut acc: Self = 1;
1905
1906            loop {
1907                if (exp & 1) == 1 {
1908                    acc = try_opt!(acc.checked_mul(base));
1909                    // since exp!=0, finally the exp must be 1.
1910                    if exp == 1 {
1911                        return Some(acc);
1912                    }
1913                }
1914                exp /= 2;
1915                base = try_opt!(base.checked_mul(base));
1916            }
1917        }
1918
1919        /// Strict exponentiation. Computes `self.pow(exp)`, panicking if
1920        /// overflow occurred.
1921        ///
1922        /// # Panics
1923        ///
1924        /// ## Overflow behavior
1925        ///
1926        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1927        ///
1928        /// # Examples
1929        ///
1930        /// ```
1931        /// #![feature(strict_overflow_ops)]
1932        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".strict_pow(5), 32);")]
1933        /// ```
1934        ///
1935        /// The following panics because of overflow:
1936        ///
1937        /// ```should_panic
1938        /// #![feature(strict_overflow_ops)]
1939        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_pow(2);")]
1940        /// ```
1941        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1942        #[must_use = "this returns the result of the operation, \
1943                      without modifying the original"]
1944        #[inline]
1945        #[track_caller]
1946        #[cfg(not(feature = "ferrocene_certified"))]
1947        pub const fn strict_pow(self, mut exp: u32) -> Self {
1948            if exp == 0 {
1949                return 1;
1950            }
1951            let mut base = self;
1952            let mut acc: Self = 1;
1953
1954            loop {
1955                if (exp & 1) == 1 {
1956                    acc = acc.strict_mul(base);
1957                    // since exp!=0, finally the exp must be 1.
1958                    if exp == 1 {
1959                        return acc;
1960                    }
1961                }
1962                exp /= 2;
1963                base = base.strict_mul(base);
1964            }
1965        }
1966
1967        /// Saturating integer addition. Computes `self + rhs`, saturating at
1968        /// the numeric bounds instead of overflowing.
1969        ///
1970        /// # Examples
1971        ///
1972        /// ```
1973        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_add(1), 101);")]
1974        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add(127), ", stringify!($SelfT), "::MAX);")]
1975        /// ```
1976        #[stable(feature = "rust1", since = "1.0.0")]
1977        #[must_use = "this returns the result of the operation, \
1978                      without modifying the original"]
1979        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1980        #[inline(always)]
1981        #[cfg(not(feature = "ferrocene_certified"))]
1982        pub const fn saturating_add(self, rhs: Self) -> Self {
1983            intrinsics::saturating_add(self, rhs)
1984        }
1985
1986        /// Saturating addition with a signed integer. Computes `self + rhs`,
1987        /// saturating at the numeric bounds instead of overflowing.
1988        ///
1989        /// # Examples
1990        ///
1991        /// ```
1992        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(2), 3);")]
1993        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(-2), 0);")]
1994        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_add_signed(4), ", stringify!($SelfT), "::MAX);")]
1995        /// ```
1996        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1997        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1998        #[must_use = "this returns the result of the operation, \
1999                      without modifying the original"]
2000        #[inline]
2001        #[cfg(not(feature = "ferrocene_certified"))]
2002        pub const fn saturating_add_signed(self, rhs: $SignedT) -> Self {
2003            let (res, overflow) = self.overflowing_add(rhs as Self);
2004            if overflow == (rhs < 0) {
2005                res
2006            } else if overflow {
2007                Self::MAX
2008            } else {
2009                0
2010            }
2011        }
2012
2013        /// Saturating integer subtraction. Computes `self - rhs`, saturating
2014        /// at the numeric bounds instead of overflowing.
2015        ///
2016        /// # Examples
2017        ///
2018        /// ```
2019        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub(27), 73);")]
2020        #[doc = concat!("assert_eq!(13", stringify!($SelfT), ".saturating_sub(127), 0);")]
2021        /// ```
2022        #[stable(feature = "rust1", since = "1.0.0")]
2023        #[must_use = "this returns the result of the operation, \
2024                      without modifying the original"]
2025        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
2026        #[inline(always)]
2027        #[cfg(not(feature = "ferrocene_certified"))]
2028        pub const fn saturating_sub(self, rhs: Self) -> Self {
2029            intrinsics::saturating_sub(self, rhs)
2030        }
2031
2032        /// Saturating integer subtraction. Computes `self` - `rhs`, saturating at
2033        /// the numeric bounds instead of overflowing.
2034        ///
2035        /// # Examples
2036        ///
2037        /// ```
2038        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_sub_signed(2), 0);")]
2039        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_sub_signed(-2), 3);")]
2040        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_sub_signed(-4), ", stringify!($SelfT), "::MAX);")]
2041        /// ```
2042        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2043        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2044        #[must_use = "this returns the result of the operation, \
2045                      without modifying the original"]
2046        #[inline]
2047        #[cfg(not(feature = "ferrocene_certified"))]
2048        pub const fn saturating_sub_signed(self, rhs: $SignedT) -> Self {
2049            let (res, overflow) = self.overflowing_sub_signed(rhs);
2050
2051            if !overflow {
2052                res
2053            } else if rhs < 0 {
2054                Self::MAX
2055            } else {
2056                0
2057            }
2058        }
2059
2060        /// Saturating integer multiplication. Computes `self * rhs`,
2061        /// saturating at the numeric bounds instead of overflowing.
2062        ///
2063        /// # Examples
2064        ///
2065        /// ```
2066        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".saturating_mul(10), 20);")]
2067        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).saturating_mul(10), ", stringify!($SelfT),"::MAX);")]
2068        /// ```
2069        #[stable(feature = "wrapping", since = "1.7.0")]
2070        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
2071        #[must_use = "this returns the result of the operation, \
2072                      without modifying the original"]
2073        #[inline]
2074        #[cfg(not(feature = "ferrocene_certified"))]
2075        pub const fn saturating_mul(self, rhs: Self) -> Self {
2076            match self.checked_mul(rhs) {
2077                Some(x) => x,
2078                None => Self::MAX,
2079            }
2080        }
2081
2082        /// Saturating integer division. Computes `self / rhs`, saturating at the
2083        /// numeric bounds instead of overflowing.
2084        ///
2085        /// # Panics
2086        ///
2087        /// This function will panic if `rhs` is zero.
2088        ///
2089        /// # Examples
2090        ///
2091        /// ```
2092        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".saturating_div(2), 2);")]
2093        ///
2094        /// ```
2095        #[stable(feature = "saturating_div", since = "1.58.0")]
2096        #[rustc_const_stable(feature = "saturating_div", since = "1.58.0")]
2097        #[must_use = "this returns the result of the operation, \
2098                      without modifying the original"]
2099        #[inline]
2100        #[track_caller]
2101        #[cfg(not(feature = "ferrocene_certified"))]
2102        pub const fn saturating_div(self, rhs: Self) -> Self {
2103            // on unsigned types, there is no overflow in integer division
2104            self.wrapping_div(rhs)
2105        }
2106
2107        /// Saturating integer exponentiation. Computes `self.pow(exp)`,
2108        /// saturating at the numeric bounds instead of overflowing.
2109        ///
2110        /// # Examples
2111        ///
2112        /// ```
2113        #[doc = concat!("assert_eq!(4", stringify!($SelfT), ".saturating_pow(3), 64);")]
2114        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_pow(2), ", stringify!($SelfT), "::MAX);")]
2115        /// ```
2116        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2117        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2118        #[must_use = "this returns the result of the operation, \
2119                      without modifying the original"]
2120        #[inline]
2121        #[cfg(not(feature = "ferrocene_certified"))]
2122        pub const fn saturating_pow(self, exp: u32) -> Self {
2123            match self.checked_pow(exp) {
2124                Some(x) => x,
2125                None => Self::MAX,
2126            }
2127        }
2128
2129        /// Wrapping (modular) addition. Computes `self + rhs`,
2130        /// wrapping around at the boundary of the type.
2131        ///
2132        /// # Examples
2133        ///
2134        /// ```
2135        #[doc = concat!("assert_eq!(200", stringify!($SelfT), ".wrapping_add(55), 255);")]
2136        #[doc = concat!("assert_eq!(200", stringify!($SelfT), ".wrapping_add(", stringify!($SelfT), "::MAX), 199);")]
2137        /// ```
2138        #[stable(feature = "rust1", since = "1.0.0")]
2139        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2140        #[must_use = "this returns the result of the operation, \
2141                      without modifying the original"]
2142        #[inline(always)]
2143        #[cfg(not(feature = "ferrocene_certified"))]
2144        pub const fn wrapping_add(self, rhs: Self) -> Self {
2145            intrinsics::wrapping_add(self, rhs)
2146        }
2147
2148        /// Wrapping (modular) addition with a signed integer. Computes
2149        /// `self + rhs`, wrapping around at the boundary of the type.
2150        ///
2151        /// # Examples
2152        ///
2153        /// ```
2154        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(2), 3);")]
2155        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(-2), ", stringify!($SelfT), "::MAX);")]
2156        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_add_signed(4), 1);")]
2157        /// ```
2158        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2159        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2160        #[must_use = "this returns the result of the operation, \
2161                      without modifying the original"]
2162        #[inline]
2163        #[cfg(not(feature = "ferrocene_certified"))]
2164        pub const fn wrapping_add_signed(self, rhs: $SignedT) -> Self {
2165            self.wrapping_add(rhs as Self)
2166        }
2167
2168        /// Wrapping (modular) subtraction. Computes `self - rhs`,
2169        /// wrapping around at the boundary of the type.
2170        ///
2171        /// # Examples
2172        ///
2173        /// ```
2174        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_sub(100), 0);")]
2175        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_sub(", stringify!($SelfT), "::MAX), 101);")]
2176        /// ```
2177        #[stable(feature = "rust1", since = "1.0.0")]
2178        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2179        #[must_use = "this returns the result of the operation, \
2180                      without modifying the original"]
2181        #[inline(always)]
2182        #[cfg(not(feature = "ferrocene_certified"))]
2183        pub const fn wrapping_sub(self, rhs: Self) -> Self {
2184            intrinsics::wrapping_sub(self, rhs)
2185        }
2186
2187        /// Wrapping (modular) subtraction with a signed integer. Computes
2188        /// `self - rhs`, wrapping around at the boundary of the type.
2189        ///
2190        /// # Examples
2191        ///
2192        /// ```
2193        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_sub_signed(2), ", stringify!($SelfT), "::MAX);")]
2194        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_sub_signed(-2), 3);")]
2195        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_sub_signed(-4), 1);")]
2196        /// ```
2197        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2198        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2199        #[must_use = "this returns the result of the operation, \
2200                      without modifying the original"]
2201        #[inline]
2202        #[cfg(not(feature = "ferrocene_certified"))]
2203        pub const fn wrapping_sub_signed(self, rhs: $SignedT) -> Self {
2204            self.wrapping_sub(rhs as Self)
2205        }
2206
2207        /// Wrapping (modular) multiplication. Computes `self *
2208        /// rhs`, wrapping around at the boundary of the type.
2209        ///
2210        /// # Examples
2211        ///
2212        /// Please note that this example is shared between integer types.
2213        /// Which explains why `u8` is used here.
2214        ///
2215        /// ```
2216        /// assert_eq!(10u8.wrapping_mul(12), 120);
2217        /// assert_eq!(25u8.wrapping_mul(12), 44);
2218        /// ```
2219        #[stable(feature = "rust1", since = "1.0.0")]
2220        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2221        #[must_use = "this returns the result of the operation, \
2222                      without modifying the original"]
2223        #[inline(always)]
2224        #[cfg(not(feature = "ferrocene_certified"))]
2225        pub const fn wrapping_mul(self, rhs: Self) -> Self {
2226            intrinsics::wrapping_mul(self, rhs)
2227        }
2228
2229        /// Wrapping (modular) division. Computes `self / rhs`.
2230        ///
2231        /// Wrapped division on unsigned types is just normal division. There's
2232        /// no way wrapping could ever happen. This function exists so that all
2233        /// operations are accounted for in the wrapping operations.
2234        ///
2235        /// # Panics
2236        ///
2237        /// This function will panic if `rhs` is zero.
2238        ///
2239        /// # Examples
2240        ///
2241        /// ```
2242        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div(10), 10);")]
2243        /// ```
2244        #[stable(feature = "num_wrapping", since = "1.2.0")]
2245        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2246        #[must_use = "this returns the result of the operation, \
2247                      without modifying the original"]
2248        #[inline(always)]
2249        #[track_caller]
2250        #[cfg(not(feature = "ferrocene_certified"))]
2251        pub const fn wrapping_div(self, rhs: Self) -> Self {
2252            self / rhs
2253        }
2254
2255        /// Wrapping Euclidean division. Computes `self.div_euclid(rhs)`.
2256        ///
2257        /// Wrapped division on unsigned types is just normal division. There's
2258        /// no way wrapping could ever happen. This function exists so that all
2259        /// operations are accounted for in the wrapping operations. Since, for
2260        /// the positive integers, all common definitions of division are equal,
2261        /// this is exactly equal to `self.wrapping_div(rhs)`.
2262        ///
2263        /// # Panics
2264        ///
2265        /// This function will panic if `rhs` is zero.
2266        ///
2267        /// # Examples
2268        ///
2269        /// ```
2270        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div_euclid(10), 10);")]
2271        /// ```
2272        #[stable(feature = "euclidean_division", since = "1.38.0")]
2273        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2274        #[must_use = "this returns the result of the operation, \
2275                      without modifying the original"]
2276        #[inline(always)]
2277        #[track_caller]
2278        #[cfg(not(feature = "ferrocene_certified"))]
2279        pub const fn wrapping_div_euclid(self, rhs: Self) -> Self {
2280            self / rhs
2281        }
2282
2283        /// Wrapping (modular) remainder. Computes `self % rhs`.
2284        ///
2285        /// Wrapped remainder calculation on unsigned types is just the regular
2286        /// remainder calculation. There's no way wrapping could ever happen.
2287        /// This function exists so that all operations are accounted for in the
2288        /// wrapping operations.
2289        ///
2290        /// # Panics
2291        ///
2292        /// This function will panic if `rhs` is zero.
2293        ///
2294        /// # Examples
2295        ///
2296        /// ```
2297        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem(10), 0);")]
2298        /// ```
2299        #[stable(feature = "num_wrapping", since = "1.2.0")]
2300        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2301        #[must_use = "this returns the result of the operation, \
2302                      without modifying the original"]
2303        #[inline(always)]
2304        #[track_caller]
2305        #[cfg(not(feature = "ferrocene_certified"))]
2306        pub const fn wrapping_rem(self, rhs: Self) -> Self {
2307            self % rhs
2308        }
2309
2310        /// Wrapping Euclidean modulo. Computes `self.rem_euclid(rhs)`.
2311        ///
2312        /// Wrapped modulo calculation on unsigned types is just the regular
2313        /// remainder calculation. There's no way wrapping could ever happen.
2314        /// This function exists so that all operations are accounted for in the
2315        /// wrapping operations. Since, for the positive integers, all common
2316        /// definitions of division are equal, this is exactly equal to
2317        /// `self.wrapping_rem(rhs)`.
2318        ///
2319        /// # Panics
2320        ///
2321        /// This function will panic if `rhs` is zero.
2322        ///
2323        /// # Examples
2324        ///
2325        /// ```
2326        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem_euclid(10), 0);")]
2327        /// ```
2328        #[stable(feature = "euclidean_division", since = "1.38.0")]
2329        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2330        #[must_use = "this returns the result of the operation, \
2331                      without modifying the original"]
2332        #[inline(always)]
2333        #[track_caller]
2334        #[cfg(not(feature = "ferrocene_certified"))]
2335        pub const fn wrapping_rem_euclid(self, rhs: Self) -> Self {
2336            self % rhs
2337        }
2338
2339        /// Wrapping (modular) negation. Computes `-self`,
2340        /// wrapping around at the boundary of the type.
2341        ///
2342        /// Since unsigned types do not have negative equivalents
2343        /// all applications of this function will wrap (except for `-0`).
2344        /// For values smaller than the corresponding signed type's maximum
2345        /// the result is the same as casting the corresponding signed value.
2346        /// Any larger values are equivalent to `MAX + 1 - (val - MAX - 1)` where
2347        /// `MAX` is the corresponding signed type's maximum.
2348        ///
2349        /// # Examples
2350        ///
2351        /// ```
2352        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".wrapping_neg(), 0);")]
2353        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_neg(), 1);")]
2354        #[doc = concat!("assert_eq!(13_", stringify!($SelfT), ".wrapping_neg(), (!13) + 1);")]
2355        #[doc = concat!("assert_eq!(42_", stringify!($SelfT), ".wrapping_neg(), !(42 - 1));")]
2356        /// ```
2357        #[stable(feature = "num_wrapping", since = "1.2.0")]
2358        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2359        #[must_use = "this returns the result of the operation, \
2360                      without modifying the original"]
2361        #[inline(always)]
2362        #[cfg(not(feature = "ferrocene_certified"))]
2363        pub const fn wrapping_neg(self) -> Self {
2364            (0 as $SelfT).wrapping_sub(self)
2365        }
2366
2367        /// Panic-free bitwise shift-left; yields `self << mask(rhs)`,
2368        /// where `mask` removes any high-order bits of `rhs` that
2369        /// would cause the shift to exceed the bitwidth of the type.
2370        ///
2371        /// Note that this is *not* the same as a rotate-left; the
2372        /// RHS of a wrapping shift-left is restricted to the range
2373        /// of the type, rather than the bits shifted out of the LHS
2374        /// being returned to the other end. The primitive integer
2375        /// types all implement a [`rotate_left`](Self::rotate_left) function,
2376        /// which may be what you want instead.
2377        ///
2378        /// # Examples
2379        ///
2380        /// ```
2381        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_shl(7), 128);")]
2382        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_shl(128), 1);")]
2383        /// ```
2384        #[stable(feature = "num_wrapping", since = "1.2.0")]
2385        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2386        #[must_use = "this returns the result of the operation, \
2387                      without modifying the original"]
2388        #[inline(always)]
2389        #[cfg(not(feature = "ferrocene_certified"))]
2390        pub const fn wrapping_shl(self, rhs: u32) -> Self {
2391            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2392            // out of bounds
2393            unsafe {
2394                self.unchecked_shl(rhs & (Self::BITS - 1))
2395            }
2396        }
2397
2398        /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`,
2399        /// where `mask` removes any high-order bits of `rhs` that
2400        /// would cause the shift to exceed the bitwidth of the type.
2401        ///
2402        /// Note that this is *not* the same as a rotate-right; the
2403        /// RHS of a wrapping shift-right is restricted to the range
2404        /// of the type, rather than the bits shifted out of the LHS
2405        /// being returned to the other end. The primitive integer
2406        /// types all implement a [`rotate_right`](Self::rotate_right) function,
2407        /// which may be what you want instead.
2408        ///
2409        /// # Examples
2410        ///
2411        /// ```
2412        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".wrapping_shr(7), 1);")]
2413        #[doc = concat!("assert_eq!(128", stringify!($SelfT), ".wrapping_shr(128), 128);")]
2414        /// ```
2415        #[stable(feature = "num_wrapping", since = "1.2.0")]
2416        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2417        #[must_use = "this returns the result of the operation, \
2418                      without modifying the original"]
2419        #[inline(always)]
2420        #[cfg(not(feature = "ferrocene_certified"))]
2421        pub const fn wrapping_shr(self, rhs: u32) -> Self {
2422            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2423            // out of bounds
2424            unsafe {
2425                self.unchecked_shr(rhs & (Self::BITS - 1))
2426            }
2427        }
2428
2429        /// Wrapping (modular) exponentiation. Computes `self.pow(exp)`,
2430        /// wrapping around at the boundary of the type.
2431        ///
2432        /// # Examples
2433        ///
2434        /// ```
2435        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_pow(5), 243);")]
2436        /// assert_eq!(3u8.wrapping_pow(6), 217);
2437        /// ```
2438        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2439        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2440        #[must_use = "this returns the result of the operation, \
2441                      without modifying the original"]
2442        #[inline]
2443        #[cfg(not(feature = "ferrocene_certified"))]
2444        pub const fn wrapping_pow(self, mut exp: u32) -> Self {
2445            if exp == 0 {
2446                return 1;
2447            }
2448            let mut base = self;
2449            let mut acc: Self = 1;
2450
2451            if intrinsics::is_val_statically_known(exp) {
2452                while exp > 1 {
2453                    if (exp & 1) == 1 {
2454                        acc = acc.wrapping_mul(base);
2455                    }
2456                    exp /= 2;
2457                    base = base.wrapping_mul(base);
2458                }
2459
2460                // since exp!=0, finally the exp must be 1.
2461                // Deal with the final bit of the exponent separately, since
2462                // squaring the base afterwards is not necessary.
2463                acc.wrapping_mul(base)
2464            } else {
2465                // This is faster than the above when the exponent is not known
2466                // at compile time. We can't use the same code for the constant
2467                // exponent case because LLVM is currently unable to unroll
2468                // this loop.
2469                loop {
2470                    if (exp & 1) == 1 {
2471                        acc = acc.wrapping_mul(base);
2472                        // since exp!=0, finally the exp must be 1.
2473                        if exp == 1 {
2474                            return acc;
2475                        }
2476                    }
2477                    exp /= 2;
2478                    base = base.wrapping_mul(base);
2479                }
2480            }
2481        }
2482
2483        /// Calculates `self` + `rhs`.
2484        ///
2485        /// Returns a tuple of the addition along with a boolean indicating
2486        /// whether an arithmetic overflow would occur. If an overflow would
2487        /// have occurred then the wrapped value is returned.
2488        ///
2489        /// # Examples
2490        ///
2491        /// ```
2492        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_add(2), (7, false));")]
2493        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.overflowing_add(1), (0, true));")]
2494        /// ```
2495        #[stable(feature = "wrapping", since = "1.7.0")]
2496        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2497        #[must_use = "this returns the result of the operation, \
2498                      without modifying the original"]
2499        #[inline(always)]
2500        #[cfg(not(feature = "ferrocene_certified"))]
2501        pub const fn overflowing_add(self, rhs: Self) -> (Self, bool) {
2502            let (a, b) = intrinsics::add_with_overflow(self as $ActualT, rhs as $ActualT);
2503            (a as Self, b)
2504        }
2505
2506        /// Calculates `self` + `rhs` + `carry` and returns a tuple containing
2507        /// the sum and the output carry.
2508        ///
2509        /// Performs "ternary addition" of two integer operands and a carry-in
2510        /// bit, and returns an output integer and a carry-out bit. This allows
2511        /// chaining together multiple additions to create a wider addition, and
2512        /// can be useful for bignum addition.
2513        ///
2514        #[doc = concat!("This can be thought of as a ", stringify!($BITS), "-bit \"full adder\", in the electronics sense.")]
2515        ///
2516        /// If the input carry is false, this method is equivalent to
2517        /// [`overflowing_add`](Self::overflowing_add), and the output carry is
2518        /// equal to the overflow flag. Note that although carry and overflow
2519        /// flags are similar for unsigned integers, they are different for
2520        /// signed integers.
2521        ///
2522        /// # Examples
2523        ///
2524        /// ```
2525        /// #![feature(bigint_helper_methods)]
2526        ///
2527        #[doc = concat!("//    3  MAX    (a = 3 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2528        #[doc = concat!("// +  5    7    (b = 5 × 2^", stringify!($BITS), " + 7)")]
2529        /// // ---------
2530        #[doc = concat!("//    9    6    (sum = 9 × 2^", stringify!($BITS), " + 6)")]
2531        ///
2532        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (3, ", stringify!($SelfT), "::MAX);")]
2533        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (5, 7);")]
2534        /// let carry0 = false;
2535        ///
2536        /// let (sum0, carry1) = a0.carrying_add(b0, carry0);
2537        /// assert_eq!(carry1, true);
2538        /// let (sum1, carry2) = a1.carrying_add(b1, carry1);
2539        /// assert_eq!(carry2, false);
2540        ///
2541        /// assert_eq!((sum1, sum0), (9, 6));
2542        /// ```
2543        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2544        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2545        #[must_use = "this returns the result of the operation, \
2546                      without modifying the original"]
2547        #[inline]
2548        #[cfg(not(feature = "ferrocene_certified"))]
2549        pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) {
2550            // note: longer-term this should be done via an intrinsic, but this has been shown
2551            //   to generate optimal code for now, and LLVM doesn't have an equivalent intrinsic
2552            let (a, c1) = self.overflowing_add(rhs);
2553            let (b, c2) = a.overflowing_add(carry as $SelfT);
2554            // Ideally LLVM would know this is disjoint without us telling them,
2555            // but it doesn't <https://github.com/llvm/llvm-project/issues/118162>
2556            // SAFETY: Only one of `c1` and `c2` can be set.
2557            // For c1 to be set we need to have overflowed, but if we did then
2558            // `a` is at most `MAX-1`, which means that `c2` cannot possibly
2559            // overflow because it's adding at most `1` (since it came from `bool`)
2560            (b, unsafe { intrinsics::disjoint_bitor(c1, c2) })
2561        }
2562
2563        /// Calculates `self` + `rhs` with a signed `rhs`.
2564        ///
2565        /// Returns a tuple of the addition along with a boolean indicating
2566        /// whether an arithmetic overflow would occur. If an overflow would
2567        /// have occurred then the wrapped value is returned.
2568        ///
2569        /// # Examples
2570        ///
2571        /// ```
2572        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(2), (3, false));")]
2573        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(-2), (", stringify!($SelfT), "::MAX, true));")]
2574        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_signed(4), (1, true));")]
2575        /// ```
2576        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2577        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2578        #[must_use = "this returns the result of the operation, \
2579                      without modifying the original"]
2580        #[inline]
2581        #[cfg(not(feature = "ferrocene_certified"))]
2582        pub const fn overflowing_add_signed(self, rhs: $SignedT) -> (Self, bool) {
2583            let (res, overflowed) = self.overflowing_add(rhs as Self);
2584            (res, overflowed ^ (rhs < 0))
2585        }
2586
2587        /// Calculates `self` - `rhs`.
2588        ///
2589        /// Returns a tuple of the subtraction along with a boolean indicating
2590        /// whether an arithmetic overflow would occur. If an overflow would
2591        /// have occurred then the wrapped value is returned.
2592        ///
2593        /// # Examples
2594        ///
2595        /// ```
2596        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_sub(2), (3, false));")]
2597        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_sub(1), (", stringify!($SelfT), "::MAX, true));")]
2598        /// ```
2599        #[stable(feature = "wrapping", since = "1.7.0")]
2600        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2601        #[must_use = "this returns the result of the operation, \
2602                      without modifying the original"]
2603        #[inline(always)]
2604        #[cfg(not(feature = "ferrocene_certified"))]
2605        pub const fn overflowing_sub(self, rhs: Self) -> (Self, bool) {
2606            let (a, b) = intrinsics::sub_with_overflow(self as $ActualT, rhs as $ActualT);
2607            (a as Self, b)
2608        }
2609
2610        /// Calculates `self` &minus; `rhs` &minus; `borrow` and returns a tuple
2611        /// containing the difference and the output borrow.
2612        ///
2613        /// Performs "ternary subtraction" by subtracting both an integer
2614        /// operand and a borrow-in bit from `self`, and returns an output
2615        /// integer and a borrow-out bit. This allows chaining together multiple
2616        /// subtractions to create a wider subtraction, and can be useful for
2617        /// bignum subtraction.
2618        ///
2619        /// # Examples
2620        ///
2621        /// ```
2622        /// #![feature(bigint_helper_methods)]
2623        ///
2624        #[doc = concat!("//    9    6    (a = 9 × 2^", stringify!($BITS), " + 6)")]
2625        #[doc = concat!("// -  5    7    (b = 5 × 2^", stringify!($BITS), " + 7)")]
2626        /// // ---------
2627        #[doc = concat!("//    3  MAX    (diff = 3 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2628        ///
2629        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (9, 6);")]
2630        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($SelfT), ") = (5, 7);")]
2631        /// let borrow0 = false;
2632        ///
2633        /// let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0);
2634        /// assert_eq!(borrow1, true);
2635        /// let (diff1, borrow2) = a1.borrowing_sub(b1, borrow1);
2636        /// assert_eq!(borrow2, false);
2637        ///
2638        #[doc = concat!("assert_eq!((diff1, diff0), (3, ", stringify!($SelfT), "::MAX));")]
2639        /// ```
2640        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2641        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2642        #[must_use = "this returns the result of the operation, \
2643                      without modifying the original"]
2644        #[inline]
2645        #[cfg(not(feature = "ferrocene_certified"))]
2646        pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) {
2647            // note: longer-term this should be done via an intrinsic, but this has been shown
2648            //   to generate optimal code for now, and LLVM doesn't have an equivalent intrinsic
2649            let (a, c1) = self.overflowing_sub(rhs);
2650            let (b, c2) = a.overflowing_sub(borrow as $SelfT);
2651            // SAFETY: Only one of `c1` and `c2` can be set.
2652            // For c1 to be set we need to have underflowed, but if we did then
2653            // `a` is nonzero, which means that `c2` cannot possibly
2654            // underflow because it's subtracting at most `1` (since it came from `bool`)
2655            (b, unsafe { intrinsics::disjoint_bitor(c1, c2) })
2656        }
2657
2658        /// Calculates `self` - `rhs` with a signed `rhs`
2659        ///
2660        /// Returns a tuple of the subtraction along with a boolean indicating
2661        /// whether an arithmetic overflow would occur. If an overflow would
2662        /// have occurred then the wrapped value is returned.
2663        ///
2664        /// # Examples
2665        ///
2666        /// ```
2667        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_signed(2), (", stringify!($SelfT), "::MAX, true));")]
2668        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_signed(-2), (3, false));")]
2669        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_sub_signed(-4), (1, true));")]
2670        /// ```
2671        #[stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2672        #[rustc_const_stable(feature = "mixed_integer_ops_unsigned_sub", since = "CURRENT_RUSTC_VERSION")]
2673        #[must_use = "this returns the result of the operation, \
2674                      without modifying the original"]
2675        #[inline]
2676        #[cfg(not(feature = "ferrocene_certified"))]
2677        pub const fn overflowing_sub_signed(self, rhs: $SignedT) -> (Self, bool) {
2678            let (res, overflow) = self.overflowing_sub(rhs as Self);
2679
2680            (res, overflow ^ (rhs < 0))
2681        }
2682
2683        /// Computes the absolute difference between `self` and `other`.
2684        ///
2685        /// # Examples
2686        ///
2687        /// ```
2688        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(80), 20", stringify!($SelfT), ");")]
2689        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(110), 10", stringify!($SelfT), ");")]
2690        /// ```
2691        #[stable(feature = "int_abs_diff", since = "1.60.0")]
2692        #[rustc_const_stable(feature = "int_abs_diff", since = "1.60.0")]
2693        #[must_use = "this returns the result of the operation, \
2694                      without modifying the original"]
2695        #[inline]
2696        #[cfg(not(feature = "ferrocene_certified"))]
2697        pub const fn abs_diff(self, other: Self) -> Self {
2698            if size_of::<Self>() == 1 {
2699                // Trick LLVM into generating the psadbw instruction when SSE2
2700                // is available and this function is autovectorized for u8's.
2701                (self as i32).wrapping_sub(other as i32).unsigned_abs() as Self
2702            } else {
2703                if self < other {
2704                    other - self
2705                } else {
2706                    self - other
2707                }
2708            }
2709        }
2710
2711        /// Calculates the multiplication of `self` and `rhs`.
2712        ///
2713        /// Returns a tuple of the multiplication along with a boolean
2714        /// indicating whether an arithmetic overflow would occur. If an
2715        /// overflow would have occurred then the wrapped value is returned.
2716        ///
2717        /// # Examples
2718        ///
2719        /// Please note that this example is shared between integer types.
2720        /// Which explains why `u32` is used here.
2721        ///
2722        /// ```
2723        /// assert_eq!(5u32.overflowing_mul(2), (10, false));
2724        /// assert_eq!(1_000_000_000u32.overflowing_mul(10), (1410065408, true));
2725        /// ```
2726        #[stable(feature = "wrapping", since = "1.7.0")]
2727        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
2728        #[must_use = "this returns the result of the operation, \
2729                          without modifying the original"]
2730        #[inline(always)]
2731        #[cfg(not(feature = "ferrocene_certified"))]
2732        pub const fn overflowing_mul(self, rhs: Self) -> (Self, bool) {
2733            let (a, b) = intrinsics::mul_with_overflow(self as $ActualT, rhs as $ActualT);
2734            (a as Self, b)
2735        }
2736
2737        /// Calculates the complete product `self * rhs` without the possibility to overflow.
2738        ///
2739        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2740        /// of the result as two separate values, in that order.
2741        ///
2742        /// If you also need to add a carry to the wide result, then you want
2743        /// [`Self::carrying_mul`] instead.
2744        ///
2745        /// # Examples
2746        ///
2747        /// Please note that this example is shared between integer types.
2748        /// Which explains why `u32` is used here.
2749        ///
2750        /// ```
2751        /// #![feature(bigint_helper_methods)]
2752        /// assert_eq!(5u32.widening_mul(2), (10, 0));
2753        /// assert_eq!(1_000_000_000u32.widening_mul(10), (1410065408, 2));
2754        /// ```
2755        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2756        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2757        #[must_use = "this returns the result of the operation, \
2758                      without modifying the original"]
2759        #[inline]
2760        #[cfg(not(feature = "ferrocene_certified"))]
2761        pub const fn widening_mul(self, rhs: Self) -> (Self, Self) {
2762            Self::carrying_mul_add(self, rhs, 0, 0)
2763        }
2764
2765        /// Calculates the "full multiplication" `self * rhs + carry`
2766        /// without the possibility to overflow.
2767        ///
2768        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2769        /// of the result as two separate values, in that order.
2770        ///
2771        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2772        /// additional amount of overflow. This allows for chaining together multiple
2773        /// multiplications to create "big integers" which represent larger values.
2774        ///
2775        /// If you don't need the `carry`, then you can use [`Self::widening_mul`] instead.
2776        ///
2777        /// # Examples
2778        ///
2779        /// Please note that this example is shared between integer types.
2780        /// Which explains why `u32` is used here.
2781        ///
2782        /// ```
2783        /// #![feature(bigint_helper_methods)]
2784        /// assert_eq!(5u32.carrying_mul(2, 0), (10, 0));
2785        /// assert_eq!(5u32.carrying_mul(2, 10), (20, 0));
2786        /// assert_eq!(1_000_000_000u32.carrying_mul(10, 0), (1410065408, 2));
2787        /// assert_eq!(1_000_000_000u32.carrying_mul(10, 10), (1410065418, 2));
2788        #[doc = concat!("assert_eq!(",
2789            stringify!($SelfT), "::MAX.carrying_mul(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2790            "(0, ", stringify!($SelfT), "::MAX));"
2791        )]
2792        /// ```
2793        ///
2794        /// This is the core operation needed for scalar multiplication when
2795        /// implementing it for wider-than-native types.
2796        ///
2797        /// ```
2798        /// #![feature(bigint_helper_methods)]
2799        /// fn scalar_mul_eq(little_endian_digits: &mut Vec<u16>, multiplicand: u16) {
2800        ///     let mut carry = 0;
2801        ///     for d in little_endian_digits.iter_mut() {
2802        ///         (*d, carry) = d.carrying_mul(multiplicand, carry);
2803        ///     }
2804        ///     if carry != 0 {
2805        ///         little_endian_digits.push(carry);
2806        ///     }
2807        /// }
2808        ///
2809        /// let mut v = vec![10, 20];
2810        /// scalar_mul_eq(&mut v, 3);
2811        /// assert_eq!(v, [30, 60]);
2812        ///
2813        /// assert_eq!(0x87654321_u64 * 0xFEED, 0x86D3D159E38D);
2814        /// let mut v = vec![0x4321, 0x8765];
2815        /// scalar_mul_eq(&mut v, 0xFEED);
2816        /// assert_eq!(v, [0xE38D, 0xD159, 0x86D3]);
2817        /// ```
2818        ///
2819        /// If `carry` is zero, this is similar to [`overflowing_mul`](Self::overflowing_mul),
2820        /// except that it gives the value of the overflow instead of just whether one happened:
2821        ///
2822        /// ```
2823        /// #![feature(bigint_helper_methods)]
2824        /// let r = u8::carrying_mul(7, 13, 0);
2825        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(7, 13));
2826        /// let r = u8::carrying_mul(13, 42, 0);
2827        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(13, 42));
2828        /// ```
2829        ///
2830        /// The value of the first field in the returned tuple matches what you'd get
2831        /// by combining the [`wrapping_mul`](Self::wrapping_mul) and
2832        /// [`wrapping_add`](Self::wrapping_add) methods:
2833        ///
2834        /// ```
2835        /// #![feature(bigint_helper_methods)]
2836        /// assert_eq!(
2837        ///     789_u16.carrying_mul(456, 123).0,
2838        ///     789_u16.wrapping_mul(456).wrapping_add(123),
2839        /// );
2840        /// ```
2841        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2842        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2843        #[must_use = "this returns the result of the operation, \
2844                      without modifying the original"]
2845        #[inline]
2846        #[cfg(not(feature = "ferrocene_certified"))]
2847        pub const fn carrying_mul(self, rhs: Self, carry: Self) -> (Self, Self) {
2848            Self::carrying_mul_add(self, rhs, carry, 0)
2849        }
2850
2851        /// Calculates the "full multiplication" `self * rhs + carry1 + carry2`
2852        /// without the possibility to overflow.
2853        ///
2854        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2855        /// of the result as two separate values, in that order.
2856        ///
2857        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2858        /// additional amount of overflow. This allows for chaining together multiple
2859        /// multiplications to create "big integers" which represent larger values.
2860        ///
2861        /// If you don't need either `carry`, then you can use [`Self::widening_mul`] instead,
2862        /// and if you only need one `carry`, then you can use [`Self::carrying_mul`] instead.
2863        ///
2864        /// # Examples
2865        ///
2866        /// Please note that this example is shared between integer types,
2867        /// which explains why `u32` is used here.
2868        ///
2869        /// ```
2870        /// #![feature(bigint_helper_methods)]
2871        /// assert_eq!(5u32.carrying_mul_add(2, 0, 0), (10, 0));
2872        /// assert_eq!(5u32.carrying_mul_add(2, 10, 10), (30, 0));
2873        /// assert_eq!(1_000_000_000u32.carrying_mul_add(10, 0, 0), (1410065408, 2));
2874        /// assert_eq!(1_000_000_000u32.carrying_mul_add(10, 10, 10), (1410065428, 2));
2875        #[doc = concat!("assert_eq!(",
2876            stringify!($SelfT), "::MAX.carrying_mul_add(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2877            "(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX));"
2878        )]
2879        /// ```
2880        ///
2881        /// This is the core per-digit operation for "grade school" O(n²) multiplication.
2882        ///
2883        /// Please note that this example is shared between integer types,
2884        /// using `u8` for simplicity of the demonstration.
2885        ///
2886        /// ```
2887        /// #![feature(bigint_helper_methods)]
2888        ///
2889        /// fn quadratic_mul<const N: usize>(a: [u8; N], b: [u8; N]) -> [u8; N] {
2890        ///     let mut out = [0; N];
2891        ///     for j in 0..N {
2892        ///         let mut carry = 0;
2893        ///         for i in 0..(N - j) {
2894        ///             (out[j + i], carry) = u8::carrying_mul_add(a[i], b[j], out[j + i], carry);
2895        ///         }
2896        ///     }
2897        ///     out
2898        /// }
2899        ///
2900        /// // -1 * -1 == 1
2901        /// assert_eq!(quadratic_mul([0xFF; 3], [0xFF; 3]), [1, 0, 0]);
2902        ///
2903        /// assert_eq!(u32::wrapping_mul(0x9e3779b9, 0x7f4a7c15), 0xCFFC982D);
2904        /// assert_eq!(
2905        ///     quadratic_mul(u32::to_le_bytes(0x9e3779b9), u32::to_le_bytes(0x7f4a7c15)),
2906        ///     u32::to_le_bytes(0xCFFC982D)
2907        /// );
2908        /// ```
2909        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2910        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2911        #[must_use = "this returns the result of the operation, \
2912                      without modifying the original"]
2913        #[inline]
2914        #[cfg(not(feature = "ferrocene_certified"))]
2915        pub const fn carrying_mul_add(self, rhs: Self, carry: Self, add: Self) -> (Self, Self) {
2916            intrinsics::carrying_mul_add(self, rhs, carry, add)
2917        }
2918
2919        /// Calculates the divisor when `self` is divided by `rhs`.
2920        ///
2921        /// Returns a tuple of the divisor along with a boolean indicating
2922        /// whether an arithmetic overflow would occur. Note that for unsigned
2923        /// integers overflow never occurs, so the second value is always
2924        /// `false`.
2925        ///
2926        /// # Panics
2927        ///
2928        /// This function will panic if `rhs` is zero.
2929        ///
2930        /// # Examples
2931        ///
2932        /// ```
2933        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div(2), (2, false));")]
2934        /// ```
2935        #[inline(always)]
2936        #[stable(feature = "wrapping", since = "1.7.0")]
2937        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2938        #[must_use = "this returns the result of the operation, \
2939                      without modifying the original"]
2940        #[track_caller]
2941        #[cfg(not(feature = "ferrocene_certified"))]
2942        pub const fn overflowing_div(self, rhs: Self) -> (Self, bool) {
2943            (self / rhs, false)
2944        }
2945
2946        /// Calculates the quotient of Euclidean division `self.div_euclid(rhs)`.
2947        ///
2948        /// Returns a tuple of the divisor along with a boolean indicating
2949        /// whether an arithmetic overflow would occur. Note that for unsigned
2950        /// integers overflow never occurs, so the second value is always
2951        /// `false`.
2952        /// Since, for the positive integers, all common
2953        /// definitions of division are equal, this
2954        /// is exactly equal to `self.overflowing_div(rhs)`.
2955        ///
2956        /// # Panics
2957        ///
2958        /// This function will panic if `rhs` is zero.
2959        ///
2960        /// # Examples
2961        ///
2962        /// ```
2963        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));")]
2964        /// ```
2965        #[inline(always)]
2966        #[stable(feature = "euclidean_division", since = "1.38.0")]
2967        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2968        #[must_use = "this returns the result of the operation, \
2969                      without modifying the original"]
2970        #[track_caller]
2971        #[cfg(not(feature = "ferrocene_certified"))]
2972        pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) {
2973            (self / rhs, false)
2974        }
2975
2976        /// Calculates the remainder when `self` is divided by `rhs`.
2977        ///
2978        /// Returns a tuple of the remainder after dividing along with a boolean
2979        /// indicating whether an arithmetic overflow would occur. Note that for
2980        /// unsigned integers overflow never occurs, so the second value is
2981        /// always `false`.
2982        ///
2983        /// # Panics
2984        ///
2985        /// This function will panic if `rhs` is zero.
2986        ///
2987        /// # Examples
2988        ///
2989        /// ```
2990        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")]
2991        /// ```
2992        #[inline(always)]
2993        #[stable(feature = "wrapping", since = "1.7.0")]
2994        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2995        #[must_use = "this returns the result of the operation, \
2996                      without modifying the original"]
2997        #[track_caller]
2998        #[cfg(not(feature = "ferrocene_certified"))]
2999        pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) {
3000            (self % rhs, false)
3001        }
3002
3003        /// Calculates the remainder `self.rem_euclid(rhs)` as if by Euclidean division.
3004        ///
3005        /// Returns a tuple of the modulo after dividing along with a boolean
3006        /// indicating whether an arithmetic overflow would occur. Note that for
3007        /// unsigned integers overflow never occurs, so the second value is
3008        /// always `false`.
3009        /// Since, for the positive integers, all common
3010        /// definitions of division are equal, this operation
3011        /// is exactly equal to `self.overflowing_rem(rhs)`.
3012        ///
3013        /// # Panics
3014        ///
3015        /// This function will panic if `rhs` is zero.
3016        ///
3017        /// # Examples
3018        ///
3019        /// ```
3020        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")]
3021        /// ```
3022        #[inline(always)]
3023        #[stable(feature = "euclidean_division", since = "1.38.0")]
3024        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3025        #[must_use = "this returns the result of the operation, \
3026                      without modifying the original"]
3027        #[track_caller]
3028        #[cfg(not(feature = "ferrocene_certified"))]
3029        pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) {
3030            (self % rhs, false)
3031        }
3032
3033        /// Negates self in an overflowing fashion.
3034        ///
3035        /// Returns `!self + 1` using wrapping operations to return the value
3036        /// that represents the negation of this unsigned value. Note that for
3037        /// positive unsigned values overflow always occurs, but negating 0 does
3038        /// not overflow.
3039        ///
3040        /// # Examples
3041        ///
3042        /// ```
3043        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_neg(), (0, false));")]
3044        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".overflowing_neg(), (-2i32 as ", stringify!($SelfT), ", true));")]
3045        /// ```
3046        #[inline(always)]
3047        #[stable(feature = "wrapping", since = "1.7.0")]
3048        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
3049        #[must_use = "this returns the result of the operation, \
3050                      without modifying the original"]
3051        #[cfg(not(feature = "ferrocene_certified"))]
3052        pub const fn overflowing_neg(self) -> (Self, bool) {
3053            ((!self).wrapping_add(1), self != 0)
3054        }
3055
3056        /// Shifts self left by `rhs` bits.
3057        ///
3058        /// Returns a tuple of the shifted version of self along with a boolean
3059        /// indicating whether the shift value was larger than or equal to the
3060        /// number of bits. If the shift value is too large, then value is
3061        /// masked (N-1) where N is the number of bits, and this value is then
3062        /// used to perform the shift.
3063        ///
3064        /// # Examples
3065        ///
3066        /// ```
3067        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(4), (0x10, false));")]
3068        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(132), (0x10, true));")]
3069        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shl(", stringify!($BITS_MINUS_ONE), "), (0, false));")]
3070        /// ```
3071        #[stable(feature = "wrapping", since = "1.7.0")]
3072        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
3073        #[must_use = "this returns the result of the operation, \
3074                      without modifying the original"]
3075        #[inline(always)]
3076        #[cfg(not(feature = "ferrocene_certified"))]
3077        pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) {
3078            (self.wrapping_shl(rhs), rhs >= Self::BITS)
3079        }
3080
3081        /// Shifts self right by `rhs` bits.
3082        ///
3083        /// Returns a tuple of the shifted version of self along with a boolean
3084        /// indicating whether the shift value was larger than or equal to the
3085        /// number of bits. If the shift value is too large, then value is
3086        /// masked (N-1) where N is the number of bits, and this value is then
3087        /// used to perform the shift.
3088        ///
3089        /// # Examples
3090        ///
3091        /// ```
3092        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(4), (0x1, false));")]
3093        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(132), (0x1, true));")]
3094        /// ```
3095        #[stable(feature = "wrapping", since = "1.7.0")]
3096        #[rustc_const_stable(feature = "const_wrapping_math", since = "1.32.0")]
3097        #[must_use = "this returns the result of the operation, \
3098                      without modifying the original"]
3099        #[inline(always)]
3100        #[cfg(not(feature = "ferrocene_certified"))]
3101        pub const fn overflowing_shr(self, rhs: u32) -> (Self, bool) {
3102            (self.wrapping_shr(rhs), rhs >= Self::BITS)
3103        }
3104
3105        /// Raises self to the power of `exp`, using exponentiation by squaring.
3106        ///
3107        /// Returns a tuple of the exponentiation along with a bool indicating
3108        /// whether an overflow happened.
3109        ///
3110        /// # Examples
3111        ///
3112        /// ```
3113        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".overflowing_pow(5), (243, false));")]
3114        /// assert_eq!(3u8.overflowing_pow(6), (217, true));
3115        /// ```
3116        #[stable(feature = "no_panic_pow", since = "1.34.0")]
3117        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3118        #[must_use = "this returns the result of the operation, \
3119                      without modifying the original"]
3120        #[inline]
3121        #[cfg(not(feature = "ferrocene_certified"))]
3122        pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) {
3123            if exp == 0{
3124                return (1,false);
3125            }
3126            let mut base = self;
3127            let mut acc: Self = 1;
3128            let mut overflown = false;
3129            // Scratch space for storing results of overflowing_mul.
3130            let mut r;
3131
3132            loop {
3133                if (exp & 1) == 1 {
3134                    r = acc.overflowing_mul(base);
3135                    // since exp!=0, finally the exp must be 1.
3136                    if exp == 1 {
3137                        r.1 |= overflown;
3138                        return r;
3139                    }
3140                    acc = r.0;
3141                    overflown |= r.1;
3142                }
3143                exp /= 2;
3144                r = base.overflowing_mul(base);
3145                base = r.0;
3146                overflown |= r.1;
3147            }
3148        }
3149
3150        /// Raises self to the power of `exp`, using exponentiation by squaring.
3151        ///
3152        /// # Examples
3153        ///
3154        /// ```
3155        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".pow(5), 32);")]
3156        /// ```
3157        #[stable(feature = "rust1", since = "1.0.0")]
3158        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3159        #[must_use = "this returns the result of the operation, \
3160                      without modifying the original"]
3161        #[inline]
3162        #[rustc_inherit_overflow_checks]
3163        #[cfg(not(feature = "ferrocene_certified"))]
3164        pub const fn pow(self, mut exp: u32) -> Self {
3165            if exp == 0 {
3166                return 1;
3167            }
3168            let mut base = self;
3169            let mut acc = 1;
3170
3171            if intrinsics::is_val_statically_known(exp) {
3172                while exp > 1 {
3173                    if (exp & 1) == 1 {
3174                        acc = acc * base;
3175                    }
3176                    exp /= 2;
3177                    base = base * base;
3178                }
3179
3180                // since exp!=0, finally the exp must be 1.
3181                // Deal with the final bit of the exponent separately, since
3182                // squaring the base afterwards is not necessary and may cause a
3183                // needless overflow.
3184                acc * base
3185            } else {
3186                // This is faster than the above when the exponent is not known
3187                // at compile time. We can't use the same code for the constant
3188                // exponent case because LLVM is currently unable to unroll
3189                // this loop.
3190                loop {
3191                    if (exp & 1) == 1 {
3192                        acc = acc * base;
3193                        // since exp!=0, finally the exp must be 1.
3194                        if exp == 1 {
3195                            return acc;
3196                        }
3197                    }
3198                    exp /= 2;
3199                    base = base * base;
3200                }
3201            }
3202        }
3203
3204        /// Returns the square root of the number, rounded down.
3205        ///
3206        /// # Examples
3207        ///
3208        /// ```
3209        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".isqrt(), 3);")]
3210        /// ```
3211        #[stable(feature = "isqrt", since = "1.84.0")]
3212        #[rustc_const_stable(feature = "isqrt", since = "1.84.0")]
3213        #[must_use = "this returns the result of the operation, \
3214                      without modifying the original"]
3215        #[inline]
3216        #[cfg(not(feature = "ferrocene_certified"))]
3217        pub const fn isqrt(self) -> Self {
3218            let result = crate::num::int_sqrt::$ActualT(self as $ActualT) as $SelfT;
3219
3220            // Inform the optimizer what the range of outputs is. If testing
3221            // `core` crashes with no panic message and a `num::int_sqrt::u*`
3222            // test failed, it's because your edits caused these assertions or
3223            // the assertions in `fn isqrt` of `nonzero.rs` to become false.
3224            //
3225            // SAFETY: Integer square root is a monotonically nondecreasing
3226            // function, which means that increasing the input will never
3227            // cause the output to decrease. Thus, since the input for unsigned
3228            // integers is bounded by `[0, <$ActualT>::MAX]`, sqrt(n) will be
3229            // bounded by `[sqrt(0), sqrt(<$ActualT>::MAX)]`.
3230            unsafe {
3231                const MAX_RESULT: $SelfT = crate::num::int_sqrt::$ActualT(<$ActualT>::MAX) as $SelfT;
3232                crate::hint::assert_unchecked(result <= MAX_RESULT);
3233            }
3234
3235            result
3236        }
3237
3238        /// Performs Euclidean division.
3239        ///
3240        /// Since, for the positive integers, all common
3241        /// definitions of division are equal, this
3242        /// is exactly equal to `self / rhs`.
3243        ///
3244        /// # Panics
3245        ///
3246        /// This function will panic if `rhs` is zero.
3247        ///
3248        /// # Examples
3249        ///
3250        /// ```
3251        #[doc = concat!("assert_eq!(7", stringify!($SelfT), ".div_euclid(4), 1); // or any other integer type")]
3252        /// ```
3253        #[stable(feature = "euclidean_division", since = "1.38.0")]
3254        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3255        #[must_use = "this returns the result of the operation, \
3256                      without modifying the original"]
3257        #[inline(always)]
3258        #[track_caller]
3259        #[cfg(not(feature = "ferrocene_certified"))]
3260        pub const fn div_euclid(self, rhs: Self) -> Self {
3261            self / rhs
3262        }
3263
3264
3265        /// Calculates the least remainder of `self (mod rhs)`.
3266        ///
3267        /// Since, for the positive integers, all common
3268        /// definitions of division are equal, this
3269        /// is exactly equal to `self % rhs`.
3270        ///
3271        /// # Panics
3272        ///
3273        /// This function will panic if `rhs` is zero.
3274        ///
3275        /// # Examples
3276        ///
3277        /// ```
3278        #[doc = concat!("assert_eq!(7", stringify!($SelfT), ".rem_euclid(4), 3); // or any other integer type")]
3279        /// ```
3280        #[doc(alias = "modulo", alias = "mod")]
3281        #[stable(feature = "euclidean_division", since = "1.38.0")]
3282        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3283        #[must_use = "this returns the result of the operation, \
3284                      without modifying the original"]
3285        #[inline(always)]
3286        #[track_caller]
3287        #[cfg(not(feature = "ferrocene_certified"))]
3288        pub const fn rem_euclid(self, rhs: Self) -> Self {
3289            self % rhs
3290        }
3291
3292        /// Calculates the quotient of `self` and `rhs`, rounding the result towards negative infinity.
3293        ///
3294        /// This is the same as performing `self / rhs` for all unsigned integers.
3295        ///
3296        /// # Panics
3297        ///
3298        /// This function will panic if `rhs` is zero.
3299        ///
3300        /// # Examples
3301        ///
3302        /// ```
3303        /// #![feature(int_roundings)]
3304        #[doc = concat!("assert_eq!(7_", stringify!($SelfT), ".div_floor(4), 1);")]
3305        /// ```
3306        #[unstable(feature = "int_roundings", issue = "88581")]
3307        #[must_use = "this returns the result of the operation, \
3308                      without modifying the original"]
3309        #[inline(always)]
3310        #[track_caller]
3311        #[cfg(not(feature = "ferrocene_certified"))]
3312        pub const fn div_floor(self, rhs: Self) -> Self {
3313            self / rhs
3314        }
3315
3316        /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity.
3317        ///
3318        /// # Panics
3319        ///
3320        /// This function will panic if `rhs` is zero.
3321        ///
3322        /// # Examples
3323        ///
3324        /// ```
3325        #[doc = concat!("assert_eq!(7_", stringify!($SelfT), ".div_ceil(4), 2);")]
3326        /// ```
3327        #[stable(feature = "int_roundings1", since = "1.73.0")]
3328        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3329        #[must_use = "this returns the result of the operation, \
3330                      without modifying the original"]
3331        #[inline]
3332        #[track_caller]
3333        #[cfg(not(feature = "ferrocene_certified"))]
3334        pub const fn div_ceil(self, rhs: Self) -> Self {
3335            let d = self / rhs;
3336            let r = self % rhs;
3337            if r > 0 {
3338                d + 1
3339            } else {
3340                d
3341            }
3342        }
3343
3344        /// Calculates the smallest value greater than or equal to `self` that
3345        /// is a multiple of `rhs`.
3346        ///
3347        /// # Panics
3348        ///
3349        /// This function will panic if `rhs` is zero.
3350        ///
3351        /// ## Overflow behavior
3352        ///
3353        /// On overflow, this function will panic if overflow checks are enabled (default in debug
3354        /// mode) and wrap if overflow checks are disabled (default in release mode).
3355        ///
3356        /// # Examples
3357        ///
3358        /// ```
3359        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(8), 16);")]
3360        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(8), 24);")]
3361        /// ```
3362        #[stable(feature = "int_roundings1", since = "1.73.0")]
3363        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3364        #[must_use = "this returns the result of the operation, \
3365                      without modifying the original"]
3366        #[inline]
3367        #[rustc_inherit_overflow_checks]
3368        #[cfg(not(feature = "ferrocene_certified"))]
3369        pub const fn next_multiple_of(self, rhs: Self) -> Self {
3370            match self % rhs {
3371                0 => self,
3372                r => self + (rhs - r)
3373            }
3374        }
3375
3376        /// Calculates the smallest value greater than or equal to `self` that
3377        /// is a multiple of `rhs`. Returns `None` if `rhs` is zero or the
3378        /// operation would result in overflow.
3379        ///
3380        /// # Examples
3381        ///
3382        /// ```
3383        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(16));")]
3384        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(24));")]
3385        #[doc = concat!("assert_eq!(1_", stringify!($SelfT), ".checked_next_multiple_of(0), None);")]
3386        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_multiple_of(2), None);")]
3387        /// ```
3388        #[stable(feature = "int_roundings1", since = "1.73.0")]
3389        #[rustc_const_stable(feature = "int_roundings1", since = "1.73.0")]
3390        #[must_use = "this returns the result of the operation, \
3391                      without modifying the original"]
3392        #[inline]
3393        #[cfg(not(feature = "ferrocene_certified"))]
3394        pub const fn checked_next_multiple_of(self, rhs: Self) -> Option<Self> {
3395            match try_opt!(self.checked_rem(rhs)) {
3396                0 => Some(self),
3397                // rhs - r cannot overflow because r is smaller than rhs
3398                r => self.checked_add(rhs - r)
3399            }
3400        }
3401
3402        /// Returns `true` if `self` is an integer multiple of `rhs`, and false otherwise.
3403        ///
3404        /// This function is equivalent to `self % rhs == 0`, except that it will not panic
3405        /// for `rhs == 0`. Instead, `0.is_multiple_of(0) == true`, and for any non-zero `n`,
3406        /// `n.is_multiple_of(0) == false`.
3407        ///
3408        /// # Examples
3409        ///
3410        /// ```
3411        #[doc = concat!("assert!(6_", stringify!($SelfT), ".is_multiple_of(2));")]
3412        #[doc = concat!("assert!(!5_", stringify!($SelfT), ".is_multiple_of(2));")]
3413        ///
3414        #[doc = concat!("assert!(0_", stringify!($SelfT), ".is_multiple_of(0));")]
3415        #[doc = concat!("assert!(!6_", stringify!($SelfT), ".is_multiple_of(0));")]
3416        /// ```
3417        #[stable(feature = "unsigned_is_multiple_of", since = "1.87.0")]
3418        #[rustc_const_stable(feature = "unsigned_is_multiple_of", since = "1.87.0")]
3419        #[must_use]
3420        #[inline]
3421        #[rustc_inherit_overflow_checks]
3422        #[cfg(not(feature = "ferrocene_certified"))]
3423        pub const fn is_multiple_of(self, rhs: Self) -> bool {
3424            match rhs {
3425                0 => self == 0,
3426                _ => self % rhs == 0,
3427            }
3428        }
3429
3430        /// Returns `true` if and only if `self == 2^k` for some unsigned integer `k`.
3431        ///
3432        /// # Examples
3433        ///
3434        /// ```
3435        #[doc = concat!("assert!(16", stringify!($SelfT), ".is_power_of_two());")]
3436        #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_power_of_two());")]
3437        /// ```
3438        #[must_use]
3439        #[stable(feature = "rust1", since = "1.0.0")]
3440        #[rustc_const_stable(feature = "const_is_power_of_two", since = "1.32.0")]
3441        #[inline(always)]
3442        pub const fn is_power_of_two(self) -> bool {
3443            self.count_ones() == 1
3444        }
3445
3446        // Returns one less than next power of two.
3447        // (For 8u8 next power of two is 8u8 and for 6u8 it is 8u8)
3448        //
3449        // 8u8.one_less_than_next_power_of_two() == 7
3450        // 6u8.one_less_than_next_power_of_two() == 7
3451        //
3452        // This method cannot overflow, as in the `next_power_of_two`
3453        // overflow cases it instead ends up returning the maximum value
3454        // of the type, and can return 0 for 0.
3455        #[inline]
3456        #[cfg(not(feature = "ferrocene_certified"))]
3457        const fn one_less_than_next_power_of_two(self) -> Self {
3458            if self <= 1 { return 0; }
3459
3460            let p = self - 1;
3461            // SAFETY: Because `p > 0`, it cannot consist entirely of leading zeros.
3462            // That means the shift is always in-bounds, and some processors
3463            // (such as intel pre-haswell) have more efficient ctlz
3464            // intrinsics when the argument is non-zero.
3465            let z = unsafe { intrinsics::ctlz_nonzero(p) };
3466            <$SelfT>::MAX >> z
3467        }
3468
3469        /// Returns the smallest power of two greater than or equal to `self`.
3470        ///
3471        /// When return value overflows (i.e., `self > (1 << (N-1))` for type
3472        /// `uN`), it panics in debug mode and the return value is wrapped to 0 in
3473        /// release mode (the only situation in which this method can return 0).
3474        ///
3475        /// # Examples
3476        ///
3477        /// ```
3478        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".next_power_of_two(), 2);")]
3479        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".next_power_of_two(), 4);")]
3480        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".next_power_of_two(), 1);")]
3481        /// ```
3482        #[stable(feature = "rust1", since = "1.0.0")]
3483        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3484        #[must_use = "this returns the result of the operation, \
3485                      without modifying the original"]
3486        #[inline]
3487        #[rustc_inherit_overflow_checks]
3488        #[cfg(not(feature = "ferrocene_certified"))]
3489        pub const fn next_power_of_two(self) -> Self {
3490            self.one_less_than_next_power_of_two() + 1
3491        }
3492
3493        /// Returns the smallest power of two greater than or equal to `self`. If
3494        /// the next power of two is greater than the type's maximum value,
3495        /// `None` is returned, otherwise the power of two is wrapped in `Some`.
3496        ///
3497        /// # Examples
3498        ///
3499        /// ```
3500        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_next_power_of_two(), Some(2));")]
3501        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".checked_next_power_of_two(), Some(4));")]
3502        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_power_of_two(), None);")]
3503        /// ```
3504        #[inline]
3505        #[stable(feature = "rust1", since = "1.0.0")]
3506        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
3507        #[must_use = "this returns the result of the operation, \
3508                      without modifying the original"]
3509        #[cfg(not(feature = "ferrocene_certified"))]
3510        pub const fn checked_next_power_of_two(self) -> Option<Self> {
3511            self.one_less_than_next_power_of_two().checked_add(1)
3512        }
3513
3514        /// Returns the smallest power of two greater than or equal to `n`. If
3515        /// the next power of two is greater than the type's maximum value,
3516        /// the return value is wrapped to `0`.
3517        ///
3518        /// # Examples
3519        ///
3520        /// ```
3521        /// #![feature(wrapping_next_power_of_two)]
3522        ///
3523        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".wrapping_next_power_of_two(), 2);")]
3524        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_next_power_of_two(), 4);")]
3525        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_next_power_of_two(), 0);")]
3526        /// ```
3527        #[inline]
3528        #[unstable(feature = "wrapping_next_power_of_two", issue = "32463",
3529                   reason = "needs decision on wrapping behavior")]
3530        #[must_use = "this returns the result of the operation, \
3531                      without modifying the original"]
3532        #[cfg(not(feature = "ferrocene_certified"))]
3533        pub const fn wrapping_next_power_of_two(self) -> Self {
3534            self.one_less_than_next_power_of_two().wrapping_add(1)
3535        }
3536
3537        /// Returns the memory representation of this integer as a byte array in
3538        /// big-endian (network) byte order.
3539        ///
3540        #[doc = $to_xe_bytes_doc]
3541        ///
3542        /// # Examples
3543        ///
3544        /// ```
3545        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_be_bytes();")]
3546        #[doc = concat!("assert_eq!(bytes, ", $be_bytes, ");")]
3547        /// ```
3548        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3549        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3550        #[must_use = "this returns the result of the operation, \
3551                      without modifying the original"]
3552        #[inline]
3553        #[cfg(not(feature = "ferrocene_certified"))]
3554        pub const fn to_be_bytes(self) -> [u8; size_of::<Self>()] {
3555            self.to_be().to_ne_bytes()
3556        }
3557
3558        /// Returns the memory representation of this integer as a byte array in
3559        /// little-endian byte order.
3560        ///
3561        #[doc = $to_xe_bytes_doc]
3562        ///
3563        /// # Examples
3564        ///
3565        /// ```
3566        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_le_bytes();")]
3567        #[doc = concat!("assert_eq!(bytes, ", $le_bytes, ");")]
3568        /// ```
3569        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3570        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3571        #[must_use = "this returns the result of the operation, \
3572                      without modifying the original"]
3573        #[inline]
3574        #[cfg(not(feature = "ferrocene_certified"))]
3575        pub const fn to_le_bytes(self) -> [u8; size_of::<Self>()] {
3576            self.to_le().to_ne_bytes()
3577        }
3578
3579        /// Returns the memory representation of this integer as a byte array in
3580        /// native byte order.
3581        ///
3582        /// As the target platform's native endianness is used, portable code
3583        /// should use [`to_be_bytes`] or [`to_le_bytes`], as appropriate,
3584        /// instead.
3585        ///
3586        #[doc = $to_xe_bytes_doc]
3587        ///
3588        /// [`to_be_bytes`]: Self::to_be_bytes
3589        /// [`to_le_bytes`]: Self::to_le_bytes
3590        ///
3591        /// # Examples
3592        ///
3593        /// ```
3594        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_ne_bytes();")]
3595        /// assert_eq!(
3596        ///     bytes,
3597        ///     if cfg!(target_endian = "big") {
3598        #[doc = concat!("        ", $be_bytes)]
3599        ///     } else {
3600        #[doc = concat!("        ", $le_bytes)]
3601        ///     }
3602        /// );
3603        /// ```
3604        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3605        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3606        #[must_use = "this returns the result of the operation, \
3607                      without modifying the original"]
3608        #[allow(unnecessary_transmutes)]
3609        // SAFETY: const sound because integers are plain old datatypes so we can always
3610        // transmute them to arrays of bytes
3611        #[inline]
3612        #[cfg(not(feature = "ferrocene_certified"))]
3613        pub const fn to_ne_bytes(self) -> [u8; size_of::<Self>()] {
3614            // SAFETY: integers are plain old datatypes so we can always transmute them to
3615            // arrays of bytes
3616            unsafe { mem::transmute(self) }
3617        }
3618
3619        /// Creates a native endian integer value from its representation
3620        /// as a byte array in big endian.
3621        ///
3622        #[doc = $from_xe_bytes_doc]
3623        ///
3624        /// # Examples
3625        ///
3626        /// ```
3627        #[doc = concat!("let value = ", stringify!($SelfT), "::from_be_bytes(", $be_bytes, ");")]
3628        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3629        /// ```
3630        ///
3631        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3632        ///
3633        /// ```
3634        #[doc = concat!("fn read_be_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3635        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3636        ///     *input = rest;
3637        #[doc = concat!("    ", stringify!($SelfT), "::from_be_bytes(int_bytes.try_into().unwrap())")]
3638        /// }
3639        /// ```
3640        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3641        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3642        #[must_use]
3643        #[inline]
3644        #[cfg(not(feature = "ferrocene_certified"))]
3645        pub const fn from_be_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3646            Self::from_be(Self::from_ne_bytes(bytes))
3647        }
3648
3649        /// Creates a native endian integer value from its representation
3650        /// as a byte array in little endian.
3651        ///
3652        #[doc = $from_xe_bytes_doc]
3653        ///
3654        /// # Examples
3655        ///
3656        /// ```
3657        #[doc = concat!("let value = ", stringify!($SelfT), "::from_le_bytes(", $le_bytes, ");")]
3658        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3659        /// ```
3660        ///
3661        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3662        ///
3663        /// ```
3664        #[doc = concat!("fn read_le_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3665        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3666        ///     *input = rest;
3667        #[doc = concat!("    ", stringify!($SelfT), "::from_le_bytes(int_bytes.try_into().unwrap())")]
3668        /// }
3669        /// ```
3670        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3671        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3672        #[must_use]
3673        #[inline]
3674        #[cfg(not(feature = "ferrocene_certified"))]
3675        pub const fn from_le_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3676            Self::from_le(Self::from_ne_bytes(bytes))
3677        }
3678
3679        /// Creates a native endian integer value from its memory representation
3680        /// as a byte array in native endianness.
3681        ///
3682        /// As the target platform's native endianness is used, portable code
3683        /// likely wants to use [`from_be_bytes`] or [`from_le_bytes`], as
3684        /// appropriate instead.
3685        ///
3686        /// [`from_be_bytes`]: Self::from_be_bytes
3687        /// [`from_le_bytes`]: Self::from_le_bytes
3688        ///
3689        #[doc = $from_xe_bytes_doc]
3690        ///
3691        /// # Examples
3692        ///
3693        /// ```
3694        #[doc = concat!("let value = ", stringify!($SelfT), "::from_ne_bytes(if cfg!(target_endian = \"big\") {")]
3695        #[doc = concat!("    ", $be_bytes, "")]
3696        /// } else {
3697        #[doc = concat!("    ", $le_bytes, "")]
3698        /// });
3699        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3700        /// ```
3701        ///
3702        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3703        ///
3704        /// ```
3705        #[doc = concat!("fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3706        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3707        ///     *input = rest;
3708        #[doc = concat!("    ", stringify!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())")]
3709        /// }
3710        /// ```
3711        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3712        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3713        #[allow(unnecessary_transmutes)]
3714        #[must_use]
3715        // SAFETY: const sound because integers are plain old datatypes so we can always
3716        // transmute to them
3717        #[inline]
3718        #[cfg(not(feature = "ferrocene_certified"))]
3719        pub const fn from_ne_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3720            // SAFETY: integers are plain old datatypes so we can always transmute to them
3721            unsafe { mem::transmute(bytes) }
3722        }
3723
3724        /// New code should prefer to use
3725        #[doc = concat!("[`", stringify!($SelfT), "::MIN", "`] instead.")]
3726        ///
3727        /// Returns the smallest value that can be represented by this integer type.
3728        #[stable(feature = "rust1", since = "1.0.0")]
3729        #[rustc_promotable]
3730        #[inline(always)]
3731        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3732        #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")]
3733        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value")]
3734        #[cfg(not(feature = "ferrocene_certified"))]
3735        pub const fn min_value() -> Self { Self::MIN }
3736
3737        /// New code should prefer to use
3738        #[doc = concat!("[`", stringify!($SelfT), "::MAX", "`] instead.")]
3739        ///
3740        /// Returns the largest value that can be represented by this integer type.
3741        #[stable(feature = "rust1", since = "1.0.0")]
3742        #[rustc_promotable]
3743        #[inline(always)]
3744        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3745        #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")]
3746        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value")]
3747        #[cfg(not(feature = "ferrocene_certified"))]
3748        pub const fn max_value() -> Self { Self::MAX }
3749    }
3750}