core/num/
int_macros.rs

1macro_rules! int_impl {
2    (
3        Self = $SelfT:ty,
4        ActualT = $ActualT:ident,
5        UnsignedT = $UnsignedT:ty,
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        Min = $Min:literal,
14        Max = $Max:literal,
15        rot = $rot:literal,
16        rot_op = $rot_op:literal,
17        rot_result = $rot_result:literal,
18        swap_op = $swap_op:literal,
19        swapped = $swapped:literal,
20        reversed = $reversed:literal,
21        le_bytes = $le_bytes:literal,
22        be_bytes = $be_bytes:literal,
23        to_xe_bytes_doc = $to_xe_bytes_doc:expr,
24        from_xe_bytes_doc = $from_xe_bytes_doc:expr,
25        bound_condition = $bound_condition:literal,
26    ) => {
27        /// The smallest value that can be represented by this integer type
28        #[doc = concat!("(&minus;2<sup>", $BITS_MINUS_ONE, "</sup>", $bound_condition, ").")]
29        ///
30        /// # Examples
31        ///
32        /// ```
33        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN, ", stringify!($Min), ");")]
34        /// ```
35        #[stable(feature = "assoc_int_consts", since = "1.43.0")]
36        pub const MIN: Self = !Self::MAX;
37
38        /// The largest value that can be represented by this integer type
39        #[doc = concat!("(2<sup>", $BITS_MINUS_ONE, "</sup> &minus; 1", $bound_condition, ").")]
40        ///
41        /// # Examples
42        ///
43        /// ```
44        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX, ", stringify!($Max), ");")]
45        /// ```
46        #[stable(feature = "assoc_int_consts", since = "1.43.0")]
47        pub const MAX: Self = (<$UnsignedT>::MAX >> 1) as Self;
48
49        /// The size of this integer type in bits.
50        ///
51        /// # Examples
52        ///
53        /// ```
54        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::BITS, ", stringify!($BITS), ");")]
55        /// ```
56        #[stable(feature = "int_bits_const", since = "1.53.0")]
57        pub const BITS: u32 = <$UnsignedT>::BITS;
58
59        /// Returns the number of ones in the binary representation of `self`.
60        ///
61        /// # Examples
62        ///
63        /// ```
64        #[doc = concat!("let n = 0b100_0000", stringify!($SelfT), ";")]
65        ///
66        /// assert_eq!(n.count_ones(), 1);
67        /// ```
68        ///
69        #[stable(feature = "rust1", since = "1.0.0")]
70        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
71        #[doc(alias = "popcount")]
72        #[doc(alias = "popcnt")]
73        #[must_use = "this returns the result of the operation, \
74                      without modifying the original"]
75        #[inline(always)]
76        pub const fn count_ones(self) -> u32 { (self as $UnsignedT).count_ones() }
77
78        /// Returns the number of zeros in the binary representation of `self`.
79        ///
80        /// # Examples
81        ///
82        /// ```
83        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.count_zeros(), 1);")]
84        /// ```
85        #[stable(feature = "rust1", since = "1.0.0")]
86        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
87        #[must_use = "this returns the result of the operation, \
88                      without modifying the original"]
89        #[inline(always)]
90        pub const fn count_zeros(self) -> u32 {
91            (!self).count_ones()
92        }
93
94        /// Returns the number of leading zeros in the binary representation of `self`.
95        ///
96        /// Depending on what you're doing with the value, you might also be interested in the
97        /// [`ilog2`] function which returns a consistent number, even if the type widens.
98        ///
99        /// # Examples
100        ///
101        /// ```
102        #[doc = concat!("let n = -1", stringify!($SelfT), ";")]
103        ///
104        /// assert_eq!(n.leading_zeros(), 0);
105        /// ```
106        #[doc = concat!("[`ilog2`]: ", stringify!($SelfT), "::ilog2")]
107        #[stable(feature = "rust1", since = "1.0.0")]
108        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
109        #[must_use = "this returns the result of the operation, \
110                      without modifying the original"]
111        #[inline(always)]
112        pub const fn leading_zeros(self) -> u32 {
113            (self as $UnsignedT).leading_zeros()
114        }
115
116        /// Returns the number of trailing zeros in the binary representation of `self`.
117        ///
118        /// # Examples
119        ///
120        /// ```
121        #[doc = concat!("let n = -4", stringify!($SelfT), ";")]
122        ///
123        /// assert_eq!(n.trailing_zeros(), 2);
124        /// ```
125        #[stable(feature = "rust1", since = "1.0.0")]
126        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
127        #[must_use = "this returns the result of the operation, \
128                      without modifying the original"]
129        #[inline(always)]
130        pub const fn trailing_zeros(self) -> u32 {
131            (self as $UnsignedT).trailing_zeros()
132        }
133
134        /// Returns the number of leading ones in the binary representation of `self`.
135        ///
136        /// # Examples
137        ///
138        /// ```
139        #[doc = concat!("let n = -1", stringify!($SelfT), ";")]
140        ///
141        #[doc = concat!("assert_eq!(n.leading_ones(), ", stringify!($BITS), ");")]
142        /// ```
143        #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
144        #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
145        #[must_use = "this returns the result of the operation, \
146                      without modifying the original"]
147        #[inline(always)]
148        pub const fn leading_ones(self) -> u32 {
149            (self as $UnsignedT).leading_ones()
150        }
151
152        /// Returns the number of trailing ones in the binary representation of `self`.
153        ///
154        /// # Examples
155        ///
156        /// ```
157        #[doc = concat!("let n = 3", stringify!($SelfT), ";")]
158        ///
159        /// assert_eq!(n.trailing_ones(), 2);
160        /// ```
161        #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
162        #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
163        #[must_use = "this returns the result of the operation, \
164                      without modifying the original"]
165        #[inline(always)]
166        pub const fn trailing_ones(self) -> u32 {
167            (self as $UnsignedT).trailing_ones()
168        }
169
170        /// Returns `self` with only the most significant bit set, or `0` if
171        /// the input is `0`.
172        ///
173        /// # Examples
174        ///
175        /// ```
176        /// #![feature(isolate_most_least_significant_one)]
177        ///
178        #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
179        ///
180        /// assert_eq!(n.isolate_most_significant_one(), 0b_01000000);
181        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_most_significant_one(), 0);")]
182        /// ```
183        #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
184        #[must_use = "this returns the result of the operation, \
185                      without modifying the original"]
186        #[inline(always)]
187        pub const fn isolate_most_significant_one(self) -> Self {
188            self & (((1 as $SelfT) << (<$SelfT>::BITS - 1)).wrapping_shr(self.leading_zeros()))
189        }
190
191        /// Returns `self` with only the least significant bit set, or `0` if
192        /// the input is `0`.
193        ///
194        /// # Examples
195        ///
196        /// ```
197        /// #![feature(isolate_most_least_significant_one)]
198        ///
199        #[doc = concat!("let n: ", stringify!($SelfT), " = 0b_01100100;")]
200        ///
201        /// assert_eq!(n.isolate_least_significant_one(), 0b_00000100);
202        #[doc = concat!("assert_eq!(0_", stringify!($SelfT), ".isolate_least_significant_one(), 0);")]
203        /// ```
204        #[unstable(feature = "isolate_most_least_significant_one", issue = "136909")]
205        #[must_use = "this returns the result of the operation, \
206                      without modifying the original"]
207        #[inline(always)]
208        pub const fn isolate_least_significant_one(self) -> Self {
209            self & self.wrapping_neg()
210        }
211
212        /// Returns the bit pattern of `self` reinterpreted as an unsigned integer of the same size.
213        ///
214        /// This produces the same result as an `as` cast, but ensures that the bit-width remains
215        /// the same.
216        ///
217        /// # Examples
218        ///
219        /// ```
220        #[doc = concat!("let n = -1", stringify!($SelfT), ";")]
221        ///
222        #[doc = concat!("assert_eq!(n.cast_unsigned(), ", stringify!($UnsignedT), "::MAX);")]
223        /// ```
224        #[stable(feature = "integer_sign_cast", since = "1.87.0")]
225        #[rustc_const_stable(feature = "integer_sign_cast", since = "1.87.0")]
226        #[must_use = "this returns the result of the operation, \
227                      without modifying the original"]
228        #[inline(always)]
229        pub const fn cast_unsigned(self) -> $UnsignedT {
230            self as $UnsignedT
231        }
232
233        /// Shifts the bits to the left by a specified amount, `n`,
234        /// wrapping the truncated bits to the end of the resulting integer.
235        ///
236        /// Please note this isn't the same operation as the `<<` shifting operator!
237        ///
238        /// # Examples
239        ///
240        /// ```
241        #[doc = concat!("let n = ", $rot_op, stringify!($SelfT), ";")]
242        #[doc = concat!("let m = ", $rot_result, ";")]
243        ///
244        #[doc = concat!("assert_eq!(n.rotate_left(", $rot, "), m);")]
245        /// ```
246        #[stable(feature = "rust1", since = "1.0.0")]
247        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
248        #[must_use = "this returns the result of the operation, \
249                      without modifying the original"]
250        #[inline(always)]
251        pub const fn rotate_left(self, n: u32) -> Self {
252            (self as $UnsignedT).rotate_left(n) as Self
253        }
254
255        /// Shifts the bits to the right by a specified amount, `n`,
256        /// wrapping the truncated bits to the beginning of the resulting
257        /// integer.
258        ///
259        /// Please note this isn't the same operation as the `>>` shifting operator!
260        ///
261        /// # Examples
262        ///
263        /// ```
264        #[doc = concat!("let n = ", $rot_result, stringify!($SelfT), ";")]
265        #[doc = concat!("let m = ", $rot_op, ";")]
266        ///
267        #[doc = concat!("assert_eq!(n.rotate_right(", $rot, "), m);")]
268        /// ```
269        #[stable(feature = "rust1", since = "1.0.0")]
270        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
271        #[must_use = "this returns the result of the operation, \
272                      without modifying the original"]
273        #[inline(always)]
274        pub const fn rotate_right(self, n: u32) -> Self {
275            (self as $UnsignedT).rotate_right(n) as Self
276        }
277
278        /// Reverses the byte order of the integer.
279        ///
280        /// # Examples
281        ///
282        /// ```
283        #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")]
284        ///
285        /// let m = n.swap_bytes();
286        ///
287        #[doc = concat!("assert_eq!(m, ", $swapped, ");")]
288        /// ```
289        #[stable(feature = "rust1", since = "1.0.0")]
290        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
291        #[must_use = "this returns the result of the operation, \
292                      without modifying the original"]
293        #[inline(always)]
294        pub const fn swap_bytes(self) -> Self {
295            (self as $UnsignedT).swap_bytes() as Self
296        }
297
298        /// Reverses the order of bits in the integer. The least significant bit becomes the most significant bit,
299        ///                 second least-significant bit becomes second most-significant bit, etc.
300        ///
301        /// # Examples
302        ///
303        /// ```
304        #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")]
305        /// let m = n.reverse_bits();
306        ///
307        #[doc = concat!("assert_eq!(m, ", $reversed, ");")]
308        #[doc = concat!("assert_eq!(0, 0", stringify!($SelfT), ".reverse_bits());")]
309        /// ```
310        #[stable(feature = "reverse_bits", since = "1.37.0")]
311        #[rustc_const_stable(feature = "reverse_bits", since = "1.37.0")]
312        #[must_use = "this returns the result of the operation, \
313                      without modifying the original"]
314        #[inline(always)]
315        pub const fn reverse_bits(self) -> Self {
316            (self as $UnsignedT).reverse_bits() as Self
317        }
318
319        /// Converts an integer from big endian to the target's endianness.
320        ///
321        /// On big endian this is a no-op. On little endian the bytes are swapped.
322        ///
323        /// # Examples
324        ///
325        /// ```
326        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
327        ///
328        /// if cfg!(target_endian = "big") {
329        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_be(n), n)")]
330        /// } else {
331        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_be(n), n.swap_bytes())")]
332        /// }
333        /// ```
334        #[stable(feature = "rust1", since = "1.0.0")]
335        #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")]
336        #[must_use]
337        #[inline]
338        pub const fn from_be(x: Self) -> Self {
339            #[cfg(target_endian = "big")]
340            {
341                x
342            }
343            #[cfg(not(target_endian = "big"))]
344            {
345                x.swap_bytes()
346            }
347        }
348
349        /// Converts an integer from little endian to the target's endianness.
350        ///
351        /// On little endian this is a no-op. On big endian the bytes are swapped.
352        ///
353        /// # Examples
354        ///
355        /// ```
356        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
357        ///
358        /// if cfg!(target_endian = "little") {
359        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_le(n), n)")]
360        /// } else {
361        #[doc = concat!("    assert_eq!(", stringify!($SelfT), "::from_le(n), n.swap_bytes())")]
362        /// }
363        /// ```
364        #[stable(feature = "rust1", since = "1.0.0")]
365        #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")]
366        #[must_use]
367        #[inline]
368        pub const fn from_le(x: Self) -> Self {
369            #[cfg(target_endian = "little")]
370            {
371                x
372            }
373            #[cfg(not(target_endian = "little"))]
374            {
375                x.swap_bytes()
376            }
377        }
378
379        /// Converts `self` to big endian from the target's endianness.
380        ///
381        /// On big endian this is a no-op. On little endian the bytes are swapped.
382        ///
383        /// # Examples
384        ///
385        /// ```
386        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
387        ///
388        /// if cfg!(target_endian = "big") {
389        ///     assert_eq!(n.to_be(), n)
390        /// } else {
391        ///     assert_eq!(n.to_be(), n.swap_bytes())
392        /// }
393        /// ```
394        #[stable(feature = "rust1", since = "1.0.0")]
395        #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")]
396        #[must_use = "this returns the result of the operation, \
397                      without modifying the original"]
398        #[inline]
399        pub const fn to_be(self) -> Self { // or not to be?
400            #[cfg(target_endian = "big")]
401            {
402                self
403            }
404            #[cfg(not(target_endian = "big"))]
405            {
406                self.swap_bytes()
407            }
408        }
409
410        /// Converts `self` to little endian from the target's endianness.
411        ///
412        /// On little endian this is a no-op. On big endian the bytes are swapped.
413        ///
414        /// # Examples
415        ///
416        /// ```
417        #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")]
418        ///
419        /// if cfg!(target_endian = "little") {
420        ///     assert_eq!(n.to_le(), n)
421        /// } else {
422        ///     assert_eq!(n.to_le(), n.swap_bytes())
423        /// }
424        /// ```
425        #[stable(feature = "rust1", since = "1.0.0")]
426        #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")]
427        #[must_use = "this returns the result of the operation, \
428                      without modifying the original"]
429        #[inline]
430        pub const fn to_le(self) -> Self {
431            #[cfg(target_endian = "little")]
432            {
433                self
434            }
435            #[cfg(not(target_endian = "little"))]
436            {
437                self.swap_bytes()
438            }
439        }
440
441        /// Checked integer addition. Computes `self + rhs`, returning `None`
442        /// if overflow occurred.
443        ///
444        /// # Examples
445        ///
446        /// ```
447        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(1), Some(", stringify!($SelfT), "::MAX - 1));")]
448        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(3), None);")]
449        /// ```
450        #[stable(feature = "rust1", since = "1.0.0")]
451        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
452        #[must_use = "this returns the result of the operation, \
453                      without modifying the original"]
454        #[inline]
455        pub const fn checked_add(self, rhs: Self) -> Option<Self> {
456            let (a, b) = self.overflowing_add(rhs);
457            if intrinsics::unlikely(b) { None } else { Some(a) }
458        }
459
460        /// Strict integer addition. Computes `self + rhs`, panicking
461        /// if overflow occurred.
462        ///
463        /// # Panics
464        ///
465        /// ## Overflow behavior
466        ///
467        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
468        ///
469        /// # Examples
470        ///
471        /// ```
472        /// #![feature(strict_overflow_ops)]
473        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).strict_add(1), ", stringify!($SelfT), "::MAX - 1);")]
474        /// ```
475        ///
476        /// The following panics because of overflow:
477        ///
478        /// ```should_panic
479        /// #![feature(strict_overflow_ops)]
480        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add(3);")]
481        /// ```
482        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
483        #[must_use = "this returns the result of the operation, \
484                      without modifying the original"]
485        #[inline]
486        #[track_caller]
487        pub const fn strict_add(self, rhs: Self) -> Self {
488            let (a, b) = self.overflowing_add(rhs);
489            if b { overflow_panic::add() } else { a }
490        }
491
492        /// Unchecked integer addition. Computes `self + rhs`, assuming overflow
493        /// cannot occur.
494        ///
495        /// Calling `x.unchecked_add(y)` is semantically equivalent to calling
496        /// `x.`[`checked_add`]`(y).`[`unwrap_unchecked`]`()`.
497        ///
498        /// If you're just trying to avoid the panic in debug mode, then **do not**
499        /// use this.  Instead, you're looking for [`wrapping_add`].
500        ///
501        /// # Safety
502        ///
503        /// This results in undefined behavior when
504        #[doc = concat!("`self + rhs > ", stringify!($SelfT), "::MAX` or `self + rhs < ", stringify!($SelfT), "::MIN`,")]
505        /// i.e. when [`checked_add`] would return `None`.
506        ///
507        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
508        #[doc = concat!("[`checked_add`]: ", stringify!($SelfT), "::checked_add")]
509        #[doc = concat!("[`wrapping_add`]: ", stringify!($SelfT), "::wrapping_add")]
510        #[stable(feature = "unchecked_math", since = "1.79.0")]
511        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
512        #[must_use = "this returns the result of the operation, \
513                      without modifying the original"]
514        #[inline(always)]
515        #[track_caller]
516        pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
517            assert_unsafe_precondition!(
518                check_language_ub,
519                concat!(stringify!($SelfT), "::unchecked_add cannot overflow"),
520                (
521                    lhs: $SelfT = self,
522                    rhs: $SelfT = rhs,
523                ) => !lhs.overflowing_add(rhs).1,
524            );
525
526            // SAFETY: this is guaranteed to be safe by the caller.
527            unsafe {
528                intrinsics::unchecked_add(self, rhs)
529            }
530        }
531
532        /// Checked addition with an unsigned integer. Computes `self + rhs`,
533        /// returning `None` if overflow occurred.
534        ///
535        /// # Examples
536        ///
537        /// ```
538        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_unsigned(2), Some(3));")]
539        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_unsigned(3), None);")]
540        /// ```
541        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
542        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
543        #[must_use = "this returns the result of the operation, \
544                      without modifying the original"]
545        #[inline]
546        pub const fn checked_add_unsigned(self, rhs: $UnsignedT) -> Option<Self> {
547            let (a, b) = self.overflowing_add_unsigned(rhs);
548            if intrinsics::unlikely(b) { None } else { Some(a) }
549        }
550
551        /// Strict addition with an unsigned integer. Computes `self + rhs`,
552        /// panicking if overflow occurred.
553        ///
554        /// # Panics
555        ///
556        /// ## Overflow behavior
557        ///
558        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
559        ///
560        /// # Examples
561        ///
562        /// ```
563        /// #![feature(strict_overflow_ops)]
564        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_add_unsigned(2), 3);")]
565        /// ```
566        ///
567        /// The following panics because of overflow:
568        ///
569        /// ```should_panic
570        /// #![feature(strict_overflow_ops)]
571        #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add_unsigned(3);")]
572        /// ```
573        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
574        #[must_use = "this returns the result of the operation, \
575                      without modifying the original"]
576        #[inline]
577        #[track_caller]
578        pub const fn strict_add_unsigned(self, rhs: $UnsignedT) -> Self {
579            let (a, b) = self.overflowing_add_unsigned(rhs);
580            if b { overflow_panic::add() } else { a }
581        }
582
583        /// Checked integer subtraction. Computes `self - rhs`, returning `None` if
584        /// overflow occurred.
585        ///
586        /// # Examples
587        ///
588        /// ```
589        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub(1), Some(", stringify!($SelfT), "::MIN + 1));")]
590        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub(3), None);")]
591        /// ```
592        #[stable(feature = "rust1", since = "1.0.0")]
593        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
594        #[must_use = "this returns the result of the operation, \
595                      without modifying the original"]
596        #[inline]
597        pub const fn checked_sub(self, rhs: Self) -> Option<Self> {
598            let (a, b) = self.overflowing_sub(rhs);
599            if intrinsics::unlikely(b) { None } else { Some(a) }
600        }
601
602        /// Strict integer subtraction. Computes `self - rhs`, panicking if
603        /// overflow occurred.
604        ///
605        /// # Panics
606        ///
607        /// ## Overflow behavior
608        ///
609        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
610        ///
611        /// # Examples
612        ///
613        /// ```
614        /// #![feature(strict_overflow_ops)]
615        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).strict_sub(1), ", stringify!($SelfT), "::MIN + 1);")]
616        /// ```
617        ///
618        /// The following panics because of overflow:
619        ///
620        /// ```should_panic
621        /// #![feature(strict_overflow_ops)]
622        #[doc = concat!("let _ = (", stringify!($SelfT), "::MIN + 2).strict_sub(3);")]
623        /// ```
624        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
625        #[must_use = "this returns the result of the operation, \
626                      without modifying the original"]
627        #[inline]
628        #[track_caller]
629        pub const fn strict_sub(self, rhs: Self) -> Self {
630            let (a, b) = self.overflowing_sub(rhs);
631            if b { overflow_panic::sub() } else { a }
632        }
633
634        /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow
635        /// cannot occur.
636        ///
637        /// Calling `x.unchecked_sub(y)` is semantically equivalent to calling
638        /// `x.`[`checked_sub`]`(y).`[`unwrap_unchecked`]`()`.
639        ///
640        /// If you're just trying to avoid the panic in debug mode, then **do not**
641        /// use this.  Instead, you're looking for [`wrapping_sub`].
642        ///
643        /// # Safety
644        ///
645        /// This results in undefined behavior when
646        #[doc = concat!("`self - rhs > ", stringify!($SelfT), "::MAX` or `self - rhs < ", stringify!($SelfT), "::MIN`,")]
647        /// i.e. when [`checked_sub`] would return `None`.
648        ///
649        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
650        #[doc = concat!("[`checked_sub`]: ", stringify!($SelfT), "::checked_sub")]
651        #[doc = concat!("[`wrapping_sub`]: ", stringify!($SelfT), "::wrapping_sub")]
652        #[stable(feature = "unchecked_math", since = "1.79.0")]
653        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
654        #[must_use = "this returns the result of the operation, \
655                      without modifying the original"]
656        #[inline(always)]
657        #[track_caller]
658        pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
659            assert_unsafe_precondition!(
660                check_language_ub,
661                concat!(stringify!($SelfT), "::unchecked_sub cannot overflow"),
662                (
663                    lhs: $SelfT = self,
664                    rhs: $SelfT = rhs,
665                ) => !lhs.overflowing_sub(rhs).1,
666            );
667
668            // SAFETY: this is guaranteed to be safe by the caller.
669            unsafe {
670                intrinsics::unchecked_sub(self, rhs)
671            }
672        }
673
674        /// Checked subtraction with an unsigned integer. Computes `self - rhs`,
675        /// returning `None` if overflow occurred.
676        ///
677        /// # Examples
678        ///
679        /// ```
680        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_unsigned(2), Some(-1));")]
681        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub_unsigned(3), None);")]
682        /// ```
683        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
684        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
685        #[must_use = "this returns the result of the operation, \
686                      without modifying the original"]
687        #[inline]
688        pub const fn checked_sub_unsigned(self, rhs: $UnsignedT) -> Option<Self> {
689            let (a, b) = self.overflowing_sub_unsigned(rhs);
690            if intrinsics::unlikely(b) { None } else { Some(a) }
691        }
692
693        /// Strict subtraction with an unsigned integer. Computes `self - rhs`,
694        /// panicking if overflow occurred.
695        ///
696        /// # Panics
697        ///
698        /// ## Overflow behavior
699        ///
700        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
701        ///
702        /// # Examples
703        ///
704        /// ```
705        /// #![feature(strict_overflow_ops)]
706        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_sub_unsigned(2), -1);")]
707        /// ```
708        ///
709        /// The following panics because of overflow:
710        ///
711        /// ```should_panic
712        /// #![feature(strict_overflow_ops)]
713        #[doc = concat!("let _ = (", stringify!($SelfT), "::MIN + 2).strict_sub_unsigned(3);")]
714        /// ```
715        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
716        #[must_use = "this returns the result of the operation, \
717                      without modifying the original"]
718        #[inline]
719        #[track_caller]
720        pub const fn strict_sub_unsigned(self, rhs: $UnsignedT) -> Self {
721            let (a, b) = self.overflowing_sub_unsigned(rhs);
722            if b { overflow_panic::sub() } else { a }
723        }
724
725        /// Checked integer multiplication. Computes `self * rhs`, returning `None` if
726        /// overflow occurred.
727        ///
728        /// # Examples
729        ///
730        /// ```
731        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(1), Some(", stringify!($SelfT), "::MAX));")]
732        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);")]
733        /// ```
734        #[stable(feature = "rust1", since = "1.0.0")]
735        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
736        #[must_use = "this returns the result of the operation, \
737                      without modifying the original"]
738        #[inline]
739        pub const fn checked_mul(self, rhs: Self) -> Option<Self> {
740            let (a, b) = self.overflowing_mul(rhs);
741            if intrinsics::unlikely(b) { None } else { Some(a) }
742        }
743
744        /// Strict integer multiplication. Computes `self * rhs`, panicking if
745        /// overflow occurred.
746        ///
747        /// # Panics
748        ///
749        /// ## Overflow behavior
750        ///
751        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
752        ///
753        /// # Examples
754        ///
755        /// ```
756        /// #![feature(strict_overflow_ops)]
757        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.strict_mul(1), ", stringify!($SelfT), "::MAX);")]
758        /// ```
759        ///
760        /// The following panics because of overflow:
761        ///
762        /// ``` should_panic
763        /// #![feature(strict_overflow_ops)]
764        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_mul(2);")]
765        /// ```
766        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
767        #[must_use = "this returns the result of the operation, \
768                      without modifying the original"]
769        #[inline]
770        #[track_caller]
771        pub const fn strict_mul(self, rhs: Self) -> Self {
772            let (a, b) = self.overflowing_mul(rhs);
773            if b { overflow_panic::mul() } else { a }
774        }
775
776        /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow
777        /// cannot occur.
778        ///
779        /// Calling `x.unchecked_mul(y)` is semantically equivalent to calling
780        /// `x.`[`checked_mul`]`(y).`[`unwrap_unchecked`]`()`.
781        ///
782        /// If you're just trying to avoid the panic in debug mode, then **do not**
783        /// use this.  Instead, you're looking for [`wrapping_mul`].
784        ///
785        /// # Safety
786        ///
787        /// This results in undefined behavior when
788        #[doc = concat!("`self * rhs > ", stringify!($SelfT), "::MAX` or `self * rhs < ", stringify!($SelfT), "::MIN`,")]
789        /// i.e. when [`checked_mul`] would return `None`.
790        ///
791        /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked
792        #[doc = concat!("[`checked_mul`]: ", stringify!($SelfT), "::checked_mul")]
793        #[doc = concat!("[`wrapping_mul`]: ", stringify!($SelfT), "::wrapping_mul")]
794        #[stable(feature = "unchecked_math", since = "1.79.0")]
795        #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")]
796        #[must_use = "this returns the result of the operation, \
797                      without modifying the original"]
798        #[inline(always)]
799        #[track_caller]
800        pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
801            assert_unsafe_precondition!(
802                check_language_ub,
803                concat!(stringify!($SelfT), "::unchecked_mul cannot overflow"),
804                (
805                    lhs: $SelfT = self,
806                    rhs: $SelfT = rhs,
807                ) => !lhs.overflowing_mul(rhs).1,
808            );
809
810            // SAFETY: this is guaranteed to be safe by the caller.
811            unsafe {
812                intrinsics::unchecked_mul(self, rhs)
813            }
814        }
815
816        /// Checked integer division. Computes `self / rhs`, returning `None` if `rhs == 0`
817        /// or the division results in overflow.
818        ///
819        /// # Examples
820        ///
821        /// ```
822        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).checked_div(-1), Some(", stringify!($Max), "));")]
823        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_div(-1), None);")]
824        #[doc = concat!("assert_eq!((1", stringify!($SelfT), ").checked_div(0), None);")]
825        /// ```
826        #[stable(feature = "rust1", since = "1.0.0")]
827        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
828        #[must_use = "this returns the result of the operation, \
829                      without modifying the original"]
830        #[inline]
831        pub const fn checked_div(self, rhs: Self) -> Option<Self> {
832            if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) {
833                None
834            } else {
835                // SAFETY: div by zero and by INT_MIN have been checked above
836                Some(unsafe { intrinsics::unchecked_div(self, rhs) })
837            }
838        }
839
840        /// Strict integer division. Computes `self / rhs`, panicking
841        /// if overflow occurred.
842        ///
843        /// # Panics
844        ///
845        /// This function will panic if `rhs` is zero.
846        ///
847        /// ## Overflow behavior
848        ///
849        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
850        ///
851        /// The only case where such an overflow can occur is when one divides `MIN / -1` on a signed type (where
852        /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value
853        /// that is too large to represent in the type.
854        ///
855        /// # Examples
856        ///
857        /// ```
858        /// #![feature(strict_overflow_ops)]
859        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).strict_div(-1), ", stringify!($Max), ");")]
860        /// ```
861        ///
862        /// The following panics because of overflow:
863        ///
864        /// ```should_panic
865        /// #![feature(strict_overflow_ops)]
866        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_div(-1);")]
867        /// ```
868        ///
869        /// The following panics because of division by zero:
870        ///
871        /// ```should_panic
872        /// #![feature(strict_overflow_ops)]
873        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div(0);")]
874        /// ```
875        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
876        #[must_use = "this returns the result of the operation, \
877                      without modifying the original"]
878        #[inline]
879        #[track_caller]
880        pub const fn strict_div(self, rhs: Self) -> Self {
881            let (a, b) = self.overflowing_div(rhs);
882            if b { overflow_panic::div() } else { a }
883        }
884
885        /// Checked Euclidean division. Computes `self.div_euclid(rhs)`,
886        /// returning `None` if `rhs == 0` or the division results in overflow.
887        ///
888        /// # Examples
889        ///
890        /// ```
891        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).checked_div_euclid(-1), Some(", stringify!($Max), "));")]
892        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_div_euclid(-1), None);")]
893        #[doc = concat!("assert_eq!((1", stringify!($SelfT), ").checked_div_euclid(0), None);")]
894        /// ```
895        #[stable(feature = "euclidean_division", since = "1.38.0")]
896        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
897        #[must_use = "this returns the result of the operation, \
898                      without modifying the original"]
899        #[inline]
900        pub const fn checked_div_euclid(self, rhs: Self) -> Option<Self> {
901            // Using `&` helps LLVM see that it is the same check made in division.
902            if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) {
903                None
904            } else {
905                Some(self.div_euclid(rhs))
906            }
907        }
908
909        /// Strict Euclidean division. Computes `self.div_euclid(rhs)`, panicking
910        /// if overflow occurred.
911        ///
912        /// # Panics
913        ///
914        /// This function will panic if `rhs` is zero.
915        ///
916        /// ## Overflow behavior
917        ///
918        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
919        ///
920        /// The only case where such an overflow can occur is when one divides `MIN / -1` on a signed type (where
921        /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value
922        /// that is too large to represent in the type.
923        ///
924        /// # Examples
925        ///
926        /// ```
927        /// #![feature(strict_overflow_ops)]
928        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).strict_div_euclid(-1), ", stringify!($Max), ");")]
929        /// ```
930        ///
931        /// The following panics because of overflow:
932        ///
933        /// ```should_panic
934        /// #![feature(strict_overflow_ops)]
935        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_div_euclid(-1);")]
936        /// ```
937        ///
938        /// The following panics because of division by zero:
939        ///
940        /// ```should_panic
941        /// #![feature(strict_overflow_ops)]
942        #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div_euclid(0);")]
943        /// ```
944        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
945        #[must_use = "this returns the result of the operation, \
946                      without modifying the original"]
947        #[inline]
948        #[track_caller]
949        pub const fn strict_div_euclid(self, rhs: Self) -> Self {
950            let (a, b) = self.overflowing_div_euclid(rhs);
951            if b { overflow_panic::div() } else { a }
952        }
953
954        /// Checked integer division without remainder. Computes `self / rhs`,
955        /// returning `None` if `rhs == 0`, the division results in overflow,
956        /// or `self % rhs != 0`.
957        ///
958        /// # Examples
959        ///
960        /// ```
961        /// #![feature(exact_div)]
962        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).checked_exact_div(-1), Some(", stringify!($Max), "));")]
963        #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").checked_exact_div(2), None);")]
964        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_exact_div(-1), None);")]
965        #[doc = concat!("assert_eq!((1", stringify!($SelfT), ").checked_exact_div(0), None);")]
966        /// ```
967        #[unstable(
968            feature = "exact_div",
969            issue = "139911",
970        )]
971        #[must_use = "this returns the result of the operation, \
972                      without modifying the original"]
973        #[inline]
974        pub const fn checked_exact_div(self, rhs: Self) -> Option<Self> {
975            if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) {
976                None
977            } else {
978                // SAFETY: division by zero and overflow are checked above
979                unsafe {
980                    if intrinsics::unlikely(intrinsics::unchecked_rem(self, rhs) != 0) {
981                        None
982                    } else {
983                        Some(intrinsics::exact_div(self, rhs))
984                    }
985                }
986            }
987        }
988
989        /// Checked integer division without remainder. Computes `self / rhs`.
990        ///
991        /// # Panics
992        ///
993        /// This function will panic  if `rhs == 0`, the division results in overflow,
994        /// or `self % rhs != 0`.
995        ///
996        /// # Examples
997        ///
998        /// ```
999        /// #![feature(exact_div)]
1000        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(2), 32);")]
1001        #[doc = concat!("assert_eq!(64", stringify!($SelfT), ".exact_div(32), 2);")]
1002        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).exact_div(-1), ", stringify!($Max), ");")]
1003        /// ```
1004        ///
1005        /// ```should_panic
1006        /// #![feature(exact_div)]
1007        #[doc = concat!("let _ = 65", stringify!($SelfT), ".exact_div(2);")]
1008        /// ```
1009        /// ```should_panic
1010        /// #![feature(exact_div)]
1011        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.exact_div(-1);")]
1012        /// ```
1013        #[unstable(
1014            feature = "exact_div",
1015            issue = "139911",
1016        )]
1017        #[must_use = "this returns the result of the operation, \
1018                      without modifying the original"]
1019        #[inline]
1020        pub const fn exact_div(self, rhs: Self) -> Self {
1021            match self.checked_exact_div(rhs) {
1022                Some(x) => x,
1023                None => panic!("Failed to divide without remainder"),
1024            }
1025        }
1026
1027        /// Unchecked integer division without remainder. Computes `self / rhs`.
1028        ///
1029        /// # Safety
1030        ///
1031        /// This results in undefined behavior when `rhs == 0`, `self % rhs != 0`, or
1032        #[doc = concat!("`self == ", stringify!($SelfT), "::MIN && rhs == -1`,")]
1033        /// i.e. when [`checked_exact_div`](Self::checked_exact_div) would return `None`.
1034        #[unstable(
1035            feature = "exact_div",
1036            issue = "139911",
1037        )]
1038        #[must_use = "this returns the result of the operation, \
1039                      without modifying the original"]
1040        #[inline]
1041        pub const unsafe fn unchecked_exact_div(self, rhs: Self) -> Self {
1042            assert_unsafe_precondition!(
1043                check_language_ub,
1044                concat!(stringify!($SelfT), "::unchecked_exact_div cannot overflow, divide by zero, or leave a remainder"),
1045                (
1046                    lhs: $SelfT = self,
1047                    rhs: $SelfT = rhs,
1048                ) => rhs > 0 && lhs % rhs == 0 && (lhs != <$SelfT>::MIN || rhs != -1),
1049            );
1050            // SAFETY: Same precondition
1051            unsafe { intrinsics::exact_div(self, rhs) }
1052        }
1053
1054        /// Checked integer remainder. Computes `self % rhs`, returning `None` if
1055        /// `rhs == 0` or the division results in overflow.
1056        ///
1057        /// # Examples
1058        ///
1059        /// ```
1060        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(2), Some(1));")]
1061        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(0), None);")]
1062        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_rem(-1), None);")]
1063        /// ```
1064        #[stable(feature = "wrapping", since = "1.7.0")]
1065        #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")]
1066        #[must_use = "this returns the result of the operation, \
1067                      without modifying the original"]
1068        #[inline]
1069        pub const fn checked_rem(self, rhs: Self) -> Option<Self> {
1070            if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) {
1071                None
1072            } else {
1073                // SAFETY: div by zero and by INT_MIN have been checked above
1074                Some(unsafe { intrinsics::unchecked_rem(self, rhs) })
1075            }
1076        }
1077
1078        /// Strict integer remainder. Computes `self % rhs`, panicking if
1079        /// the division results in overflow.
1080        ///
1081        /// # Panics
1082        ///
1083        /// This function will panic if `rhs` is zero.
1084        ///
1085        /// ## Overflow behavior
1086        ///
1087        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1088        ///
1089        /// The only case where such an overflow can occur is `x % y` for `MIN / -1` on a
1090        /// signed type (where `MIN` is the negative minimal value), which is invalid due to implementation artifacts.
1091        ///
1092        /// # Examples
1093        ///
1094        /// ```
1095        /// #![feature(strict_overflow_ops)]
1096        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_rem(2), 1);")]
1097        /// ```
1098        ///
1099        /// The following panics because of division by zero:
1100        ///
1101        /// ```should_panic
1102        /// #![feature(strict_overflow_ops)]
1103        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem(0);")]
1104        /// ```
1105        ///
1106        /// The following panics because of overflow:
1107        ///
1108        /// ```should_panic
1109        /// #![feature(strict_overflow_ops)]
1110        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_rem(-1);")]
1111        /// ```
1112        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1113        #[must_use = "this returns the result of the operation, \
1114                      without modifying the original"]
1115        #[inline]
1116        #[track_caller]
1117        pub const fn strict_rem(self, rhs: Self) -> Self {
1118            let (a, b) = self.overflowing_rem(rhs);
1119            if b { overflow_panic::rem() } else { a }
1120        }
1121
1122        /// Checked Euclidean remainder. Computes `self.rem_euclid(rhs)`, returning `None`
1123        /// if `rhs == 0` or the division results in overflow.
1124        ///
1125        /// # Examples
1126        ///
1127        /// ```
1128        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(2), Some(1));")]
1129        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(0), None);")]
1130        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_rem_euclid(-1), None);")]
1131        /// ```
1132        #[stable(feature = "euclidean_division", since = "1.38.0")]
1133        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
1134        #[must_use = "this returns the result of the operation, \
1135                      without modifying the original"]
1136        #[inline]
1137        pub const fn checked_rem_euclid(self, rhs: Self) -> Option<Self> {
1138            // Using `&` helps LLVM see that it is the same check made in division.
1139            if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) {
1140                None
1141            } else {
1142                Some(self.rem_euclid(rhs))
1143            }
1144        }
1145
1146        /// Strict Euclidean remainder. Computes `self.rem_euclid(rhs)`, panicking if
1147        /// the division results in overflow.
1148        ///
1149        /// # Panics
1150        ///
1151        /// This function will panic if `rhs` is zero.
1152        ///
1153        /// ## Overflow behavior
1154        ///
1155        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1156        ///
1157        /// The only case where such an overflow can occur is `x % y` for `MIN / -1` on a
1158        /// signed type (where `MIN` is the negative minimal value), which is invalid due to implementation artifacts.
1159        ///
1160        /// # Examples
1161        ///
1162        /// ```
1163        /// #![feature(strict_overflow_ops)]
1164        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_rem_euclid(2), 1);")]
1165        /// ```
1166        ///
1167        /// The following panics because of division by zero:
1168        ///
1169        /// ```should_panic
1170        /// #![feature(strict_overflow_ops)]
1171        #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem_euclid(0);")]
1172        /// ```
1173        ///
1174        /// The following panics because of overflow:
1175        ///
1176        /// ```should_panic
1177        /// #![feature(strict_overflow_ops)]
1178        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_rem_euclid(-1);")]
1179        /// ```
1180        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1181        #[must_use = "this returns the result of the operation, \
1182                      without modifying the original"]
1183        #[inline]
1184        #[track_caller]
1185        pub const fn strict_rem_euclid(self, rhs: Self) -> Self {
1186            let (a, b) = self.overflowing_rem_euclid(rhs);
1187            if b { overflow_panic::rem() } else { a }
1188        }
1189
1190        /// Checked negation. Computes `-self`, returning `None` if `self == MIN`.
1191        ///
1192        /// # Examples
1193        ///
1194        /// ```
1195        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_neg(), Some(-5));")]
1196        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_neg(), None);")]
1197        /// ```
1198        #[stable(feature = "wrapping", since = "1.7.0")]
1199        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1200        #[must_use = "this returns the result of the operation, \
1201                      without modifying the original"]
1202        #[inline]
1203        pub const fn checked_neg(self) -> Option<Self> {
1204            let (a, b) = self.overflowing_neg();
1205            if intrinsics::unlikely(b) { None } else { Some(a) }
1206        }
1207
1208        /// Unchecked negation. Computes `-self`, assuming overflow cannot occur.
1209        ///
1210        /// # Safety
1211        ///
1212        /// This results in undefined behavior when
1213        #[doc = concat!("`self == ", stringify!($SelfT), "::MIN`,")]
1214        /// i.e. when [`checked_neg`] would return `None`.
1215        ///
1216        #[doc = concat!("[`checked_neg`]: ", stringify!($SelfT), "::checked_neg")]
1217        #[unstable(
1218            feature = "unchecked_neg",
1219            reason = "niche optimization path",
1220            issue = "85122",
1221        )]
1222        #[must_use = "this returns the result of the operation, \
1223                      without modifying the original"]
1224        #[inline(always)]
1225        #[track_caller]
1226        pub const unsafe fn unchecked_neg(self) -> Self {
1227            assert_unsafe_precondition!(
1228                check_language_ub,
1229                concat!(stringify!($SelfT), "::unchecked_neg cannot overflow"),
1230                (
1231                    lhs: $SelfT = self,
1232                ) => !lhs.overflowing_neg().1,
1233            );
1234
1235            // SAFETY: this is guaranteed to be safe by the caller.
1236            unsafe {
1237                intrinsics::unchecked_sub(0, self)
1238            }
1239        }
1240
1241        /// Strict negation. Computes `-self`, panicking if `self == MIN`.
1242        ///
1243        /// # Panics
1244        ///
1245        /// ## Overflow behavior
1246        ///
1247        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1248        ///
1249        /// # Examples
1250        ///
1251        /// ```
1252        /// #![feature(strict_overflow_ops)]
1253        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_neg(), -5);")]
1254        /// ```
1255        ///
1256        /// The following panics because of overflow:
1257        ///
1258        /// ```should_panic
1259        /// #![feature(strict_overflow_ops)]
1260        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_neg();")]
1261        ///
1262        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1263        #[must_use = "this returns the result of the operation, \
1264                      without modifying the original"]
1265        #[inline]
1266        #[track_caller]
1267        pub const fn strict_neg(self) -> Self {
1268            let (a, b) = self.overflowing_neg();
1269            if b { overflow_panic::neg() } else { a }
1270        }
1271
1272        /// Checked shift left. Computes `self << rhs`, returning `None` if `rhs` is larger
1273        /// than or equal to the number of bits in `self`.
1274        ///
1275        /// # Examples
1276        ///
1277        /// ```
1278        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(4), Some(0x10));")]
1279        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(129), None);")]
1280        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(", stringify!($BITS_MINUS_ONE), "), Some(0));")]
1281        /// ```
1282        #[stable(feature = "wrapping", since = "1.7.0")]
1283        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1284        #[must_use = "this returns the result of the operation, \
1285                      without modifying the original"]
1286        #[inline]
1287        pub const fn checked_shl(self, rhs: u32) -> Option<Self> {
1288            // Not using overflowing_shl as that's a wrapping shift
1289            if rhs < Self::BITS {
1290                // SAFETY: just checked the RHS is in-range
1291                Some(unsafe { self.unchecked_shl(rhs) })
1292            } else {
1293                None
1294            }
1295        }
1296
1297        /// Strict shift left. Computes `self << rhs`, panicking if `rhs` is larger
1298        /// than or equal to the number of bits in `self`.
1299        ///
1300        /// # Panics
1301        ///
1302        /// ## Overflow behavior
1303        ///
1304        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1305        ///
1306        /// # Examples
1307        ///
1308        /// ```
1309        /// #![feature(strict_overflow_ops)]
1310        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".strict_shl(4), 0x10);")]
1311        /// ```
1312        ///
1313        /// The following panics because of overflow:
1314        ///
1315        /// ```should_panic
1316        /// #![feature(strict_overflow_ops)]
1317        #[doc = concat!("let _ = 0x1", stringify!($SelfT), ".strict_shl(129);")]
1318        /// ```
1319        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1320        #[must_use = "this returns the result of the operation, \
1321                      without modifying the original"]
1322        #[inline]
1323        #[track_caller]
1324        pub const fn strict_shl(self, rhs: u32) -> Self {
1325            let (a, b) = self.overflowing_shl(rhs);
1326            if b { overflow_panic::shl() } else { a }
1327        }
1328
1329        /// Unchecked shift left. Computes `self << rhs`, assuming that
1330        /// `rhs` is less than the number of bits in `self`.
1331        ///
1332        /// # Safety
1333        ///
1334        /// This results in undefined behavior if `rhs` is larger than
1335        /// or equal to the number of bits in `self`,
1336        /// i.e. when [`checked_shl`] would return `None`.
1337        ///
1338        #[doc = concat!("[`checked_shl`]: ", stringify!($SelfT), "::checked_shl")]
1339        #[unstable(
1340            feature = "unchecked_shifts",
1341            reason = "niche optimization path",
1342            issue = "85122",
1343        )]
1344        #[must_use = "this returns the result of the operation, \
1345                      without modifying the original"]
1346        #[inline(always)]
1347        #[track_caller]
1348        pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
1349            assert_unsafe_precondition!(
1350                check_language_ub,
1351                concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"),
1352                (
1353                    rhs: u32 = rhs,
1354                ) => rhs < <$ActualT>::BITS,
1355            );
1356
1357            // SAFETY: this is guaranteed to be safe by the caller.
1358            unsafe {
1359                intrinsics::unchecked_shl(self, rhs)
1360            }
1361        }
1362
1363        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`.
1364        ///
1365        /// If `rhs` is larger or equal to the number of bits in `self`,
1366        /// the entire value is shifted out, and `0` is returned.
1367        ///
1368        /// # Examples
1369        ///
1370        /// ```
1371        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(4), 0x10);")]
1372        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(129), 0);")]
1373        /// ```
1374        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1375        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1376        #[must_use = "this returns the result of the operation, \
1377                      without modifying the original"]
1378        #[inline]
1379        pub const fn unbounded_shl(self, rhs: u32) -> $SelfT{
1380            if rhs < Self::BITS {
1381                // SAFETY:
1382                // rhs is just checked to be in-range above
1383                unsafe { self.unchecked_shl(rhs) }
1384            } else {
1385                0
1386            }
1387        }
1388
1389        /// Checked shift right. Computes `self >> rhs`, returning `None` if `rhs` is
1390        /// larger than or equal to the number of bits in `self`.
1391        ///
1392        /// # Examples
1393        ///
1394        /// ```
1395        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(4), Some(0x1));")]
1396        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(128), None);")]
1397        /// ```
1398        #[stable(feature = "wrapping", since = "1.7.0")]
1399        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1400        #[must_use = "this returns the result of the operation, \
1401                      without modifying the original"]
1402        #[inline]
1403        pub const fn checked_shr(self, rhs: u32) -> Option<Self> {
1404            // Not using overflowing_shr as that's a wrapping shift
1405            if rhs < Self::BITS {
1406                // SAFETY: just checked the RHS is in-range
1407                Some(unsafe { self.unchecked_shr(rhs) })
1408            } else {
1409                None
1410            }
1411        }
1412
1413        /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is
1414        /// larger than or equal to the number of bits in `self`.
1415        ///
1416        /// # Panics
1417        ///
1418        /// ## Overflow behavior
1419        ///
1420        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1421        ///
1422        /// # Examples
1423        ///
1424        /// ```
1425        /// #![feature(strict_overflow_ops)]
1426        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".strict_shr(4), 0x1);")]
1427        /// ```
1428        ///
1429        /// The following panics because of overflow:
1430        ///
1431        /// ```should_panic
1432        /// #![feature(strict_overflow_ops)]
1433        #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shr(128);")]
1434        /// ```
1435        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1436        #[must_use = "this returns the result of the operation, \
1437                      without modifying the original"]
1438        #[inline]
1439        #[track_caller]
1440        pub const fn strict_shr(self, rhs: u32) -> Self {
1441            let (a, b) = self.overflowing_shr(rhs);
1442            if b { overflow_panic::shr() } else { a }
1443        }
1444
1445        /// Unchecked shift right. Computes `self >> rhs`, assuming that
1446        /// `rhs` is less than the number of bits in `self`.
1447        ///
1448        /// # Safety
1449        ///
1450        /// This results in undefined behavior if `rhs` is larger than
1451        /// or equal to the number of bits in `self`,
1452        /// i.e. when [`checked_shr`] would return `None`.
1453        ///
1454        #[doc = concat!("[`checked_shr`]: ", stringify!($SelfT), "::checked_shr")]
1455        #[unstable(
1456            feature = "unchecked_shifts",
1457            reason = "niche optimization path",
1458            issue = "85122",
1459        )]
1460        #[must_use = "this returns the result of the operation, \
1461                      without modifying the original"]
1462        #[inline(always)]
1463        #[track_caller]
1464        pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
1465            assert_unsafe_precondition!(
1466                check_language_ub,
1467                concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"),
1468                (
1469                    rhs: u32 = rhs,
1470                ) => rhs < <$ActualT>::BITS,
1471            );
1472
1473            // SAFETY: this is guaranteed to be safe by the caller.
1474            unsafe {
1475                intrinsics::unchecked_shr(self, rhs)
1476            }
1477        }
1478
1479        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`.
1480        ///
1481        /// If `rhs` is larger or equal to the number of bits in `self`,
1482        /// the entire value is shifted out, which yields `0` for a positive number,
1483        /// and `-1` for a negative number.
1484        ///
1485        /// # Examples
1486        ///
1487        /// ```
1488        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(4), 0x1);")]
1489        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(129), 0);")]
1490        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.unbounded_shr(129), -1);")]
1491        /// ```
1492        #[stable(feature = "unbounded_shifts", since = "1.87.0")]
1493        #[rustc_const_stable(feature = "unbounded_shifts", since = "1.87.0")]
1494        #[must_use = "this returns the result of the operation, \
1495                      without modifying the original"]
1496        #[inline]
1497        pub const fn unbounded_shr(self, rhs: u32) -> $SelfT{
1498            if rhs < Self::BITS {
1499                // SAFETY:
1500                // rhs is just checked to be in-range above
1501                unsafe { self.unchecked_shr(rhs) }
1502            } else {
1503                // A shift by `Self::BITS-1` suffices for signed integers, because the sign bit is copied for each of the shifted bits.
1504
1505                // SAFETY:
1506                // `Self::BITS-1` is guaranteed to be less than `Self::BITS`
1507                unsafe { self.unchecked_shr(Self::BITS - 1) }
1508            }
1509        }
1510
1511        /// Checked absolute value. Computes `self.abs()`, returning `None` if
1512        /// `self == MIN`.
1513        ///
1514        /// # Examples
1515        ///
1516        /// ```
1517        #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").checked_abs(), Some(5));")]
1518        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_abs(), None);")]
1519        /// ```
1520        #[stable(feature = "no_panic_abs", since = "1.13.0")]
1521        #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
1522        #[must_use = "this returns the result of the operation, \
1523                      without modifying the original"]
1524        #[inline]
1525        pub const fn checked_abs(self) -> Option<Self> {
1526            if self.is_negative() {
1527                self.checked_neg()
1528            } else {
1529                Some(self)
1530            }
1531        }
1532
1533        /// Strict absolute value. Computes `self.abs()`, panicking if
1534        /// `self == MIN`.
1535        ///
1536        /// # Panics
1537        ///
1538        /// ## Overflow behavior
1539        ///
1540        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1541        ///
1542        /// # Examples
1543        ///
1544        /// ```
1545        /// #![feature(strict_overflow_ops)]
1546        #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").strict_abs(), 5);")]
1547        /// ```
1548        ///
1549        /// The following panics because of overflow:
1550        ///
1551        /// ```should_panic
1552        /// #![feature(strict_overflow_ops)]
1553        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_abs();")]
1554        /// ```
1555        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1556        #[must_use = "this returns the result of the operation, \
1557                      without modifying the original"]
1558        #[inline]
1559        #[track_caller]
1560        pub const fn strict_abs(self) -> Self {
1561            if self.is_negative() {
1562                self.strict_neg()
1563            } else {
1564                self
1565            }
1566        }
1567
1568        /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if
1569        /// overflow occurred.
1570        ///
1571        /// # Examples
1572        ///
1573        /// ```
1574        #[doc = concat!("assert_eq!(8", stringify!($SelfT), ".checked_pow(2), Some(64));")]
1575        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_pow(2), None);")]
1576        /// ```
1577
1578        #[stable(feature = "no_panic_pow", since = "1.34.0")]
1579        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
1580        #[must_use = "this returns the result of the operation, \
1581                      without modifying the original"]
1582        #[inline]
1583        pub const fn checked_pow(self, mut exp: u32) -> Option<Self> {
1584            if exp == 0 {
1585                return Some(1);
1586            }
1587            let mut base = self;
1588            let mut acc: Self = 1;
1589
1590            loop {
1591                if (exp & 1) == 1 {
1592                    acc = try_opt!(acc.checked_mul(base));
1593                    // since exp!=0, finally the exp must be 1.
1594                    if exp == 1 {
1595                        return Some(acc);
1596                    }
1597                }
1598                exp /= 2;
1599                base = try_opt!(base.checked_mul(base));
1600            }
1601        }
1602
1603        /// Strict exponentiation. Computes `self.pow(exp)`, panicking if
1604        /// overflow occurred.
1605        ///
1606        /// # Panics
1607        ///
1608        /// ## Overflow behavior
1609        ///
1610        /// This function will always panic on overflow, regardless of whether overflow checks are enabled.
1611        ///
1612        /// # Examples
1613        ///
1614        /// ```
1615        /// #![feature(strict_overflow_ops)]
1616        #[doc = concat!("assert_eq!(8", stringify!($SelfT), ".strict_pow(2), 64);")]
1617        /// ```
1618        ///
1619        /// The following panics because of overflow:
1620        ///
1621        /// ```should_panic
1622        /// #![feature(strict_overflow_ops)]
1623        #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_pow(2);")]
1624        /// ```
1625        #[unstable(feature = "strict_overflow_ops", issue = "118260")]
1626        #[must_use = "this returns the result of the operation, \
1627                      without modifying the original"]
1628        #[inline]
1629        #[track_caller]
1630        pub const fn strict_pow(self, mut exp: u32) -> Self {
1631            if exp == 0 {
1632                return 1;
1633            }
1634            let mut base = self;
1635            let mut acc: Self = 1;
1636
1637            loop {
1638                if (exp & 1) == 1 {
1639                    acc = acc.strict_mul(base);
1640                    // since exp!=0, finally the exp must be 1.
1641                    if exp == 1 {
1642                        return acc;
1643                    }
1644                }
1645                exp /= 2;
1646                base = base.strict_mul(base);
1647            }
1648        }
1649
1650        /// Returns the square root of the number, rounded down.
1651        ///
1652        /// Returns `None` if `self` is negative.
1653        ///
1654        /// # Examples
1655        ///
1656        /// ```
1657        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_isqrt(), Some(3));")]
1658        /// ```
1659        #[stable(feature = "isqrt", since = "1.84.0")]
1660        #[rustc_const_stable(feature = "isqrt", since = "1.84.0")]
1661        #[must_use = "this returns the result of the operation, \
1662                      without modifying the original"]
1663        #[inline]
1664        pub const fn checked_isqrt(self) -> Option<Self> {
1665            if self < 0 {
1666                None
1667            } else {
1668                // SAFETY: Input is nonnegative in this `else` branch.
1669                let result = unsafe {
1670                    crate::num::int_sqrt::$ActualT(self as $ActualT) as $SelfT
1671                };
1672
1673                // Inform the optimizer what the range of outputs is. If
1674                // testing `core` crashes with no panic message and a
1675                // `num::int_sqrt::i*` test failed, it's because your edits
1676                // caused these assertions to become false.
1677                //
1678                // SAFETY: Integer square root is a monotonically nondecreasing
1679                // function, which means that increasing the input will never
1680                // cause the output to decrease. Thus, since the input for
1681                // nonnegative signed integers is bounded by
1682                // `[0, <$ActualT>::MAX]`, sqrt(n) will be bounded by
1683                // `[sqrt(0), sqrt(<$ActualT>::MAX)]`.
1684                unsafe {
1685                    // SAFETY: `<$ActualT>::MAX` is nonnegative.
1686                    const MAX_RESULT: $SelfT = unsafe {
1687                        crate::num::int_sqrt::$ActualT(<$ActualT>::MAX) as $SelfT
1688                    };
1689
1690                    crate::hint::assert_unchecked(result >= 0);
1691                    crate::hint::assert_unchecked(result <= MAX_RESULT);
1692                }
1693
1694                Some(result)
1695            }
1696        }
1697
1698        /// Saturating integer addition. Computes `self + rhs`, saturating at the numeric
1699        /// bounds instead of overflowing.
1700        ///
1701        /// # Examples
1702        ///
1703        /// ```
1704        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_add(1), 101);")]
1705        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add(100), ", stringify!($SelfT), "::MAX);")]
1706        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_add(-1), ", stringify!($SelfT), "::MIN);")]
1707        /// ```
1708
1709        #[stable(feature = "rust1", since = "1.0.0")]
1710        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1711        #[must_use = "this returns the result of the operation, \
1712                      without modifying the original"]
1713        #[inline(always)]
1714        pub const fn saturating_add(self, rhs: Self) -> Self {
1715            intrinsics::saturating_add(self, rhs)
1716        }
1717
1718        /// Saturating addition with an unsigned integer. Computes `self + rhs`,
1719        /// saturating at the numeric bounds instead of overflowing.
1720        ///
1721        /// # Examples
1722        ///
1723        /// ```
1724        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_unsigned(2), 3);")]
1725        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add_unsigned(100), ", stringify!($SelfT), "::MAX);")]
1726        /// ```
1727        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1728        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1729        #[must_use = "this returns the result of the operation, \
1730                      without modifying the original"]
1731        #[inline]
1732        pub const fn saturating_add_unsigned(self, rhs: $UnsignedT) -> Self {
1733            // Overflow can only happen at the upper bound
1734            // We cannot use `unwrap_or` here because it is not `const`
1735            match self.checked_add_unsigned(rhs) {
1736                Some(x) => x,
1737                None => Self::MAX,
1738            }
1739        }
1740
1741        /// Saturating integer subtraction. Computes `self - rhs`, saturating at the
1742        /// numeric bounds instead of overflowing.
1743        ///
1744        /// # Examples
1745        ///
1746        /// ```
1747        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub(127), -27);")]
1748        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_sub(100), ", stringify!($SelfT), "::MIN);")]
1749        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_sub(-1), ", stringify!($SelfT), "::MAX);")]
1750        /// ```
1751        #[stable(feature = "rust1", since = "1.0.0")]
1752        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1753        #[must_use = "this returns the result of the operation, \
1754                      without modifying the original"]
1755        #[inline(always)]
1756        pub const fn saturating_sub(self, rhs: Self) -> Self {
1757            intrinsics::saturating_sub(self, rhs)
1758        }
1759
1760        /// Saturating subtraction with an unsigned integer. Computes `self - rhs`,
1761        /// saturating at the numeric bounds instead of overflowing.
1762        ///
1763        /// # Examples
1764        ///
1765        /// ```
1766        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub_unsigned(127), -27);")]
1767        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_sub_unsigned(100), ", stringify!($SelfT), "::MIN);")]
1768        /// ```
1769        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1770        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1771        #[must_use = "this returns the result of the operation, \
1772                      without modifying the original"]
1773        #[inline]
1774        pub const fn saturating_sub_unsigned(self, rhs: $UnsignedT) -> Self {
1775            // Overflow can only happen at the lower bound
1776            // We cannot use `unwrap_or` here because it is not `const`
1777            match self.checked_sub_unsigned(rhs) {
1778                Some(x) => x,
1779                None => Self::MIN,
1780            }
1781        }
1782
1783        /// Saturating integer negation. Computes `-self`, returning `MAX` if `self == MIN`
1784        /// instead of overflowing.
1785        ///
1786        /// # Examples
1787        ///
1788        /// ```
1789        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_neg(), -100);")]
1790        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").saturating_neg(), 100);")]
1791        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_neg(), ", stringify!($SelfT), "::MAX);")]
1792        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_neg(), ", stringify!($SelfT), "::MIN + 1);")]
1793        /// ```
1794
1795        #[stable(feature = "saturating_neg", since = "1.45.0")]
1796        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1797        #[must_use = "this returns the result of the operation, \
1798                      without modifying the original"]
1799        #[inline(always)]
1800        pub const fn saturating_neg(self) -> Self {
1801            intrinsics::saturating_sub(0, self)
1802        }
1803
1804        /// Saturating absolute value. Computes `self.abs()`, returning `MAX` if `self ==
1805        /// MIN` instead of overflowing.
1806        ///
1807        /// # Examples
1808        ///
1809        /// ```
1810        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_abs(), 100);")]
1811        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").saturating_abs(), 100);")]
1812        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_abs(), ", stringify!($SelfT), "::MAX);")]
1813        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).saturating_abs(), ", stringify!($SelfT), "::MAX);")]
1814        /// ```
1815
1816        #[stable(feature = "saturating_neg", since = "1.45.0")]
1817        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1818        #[must_use = "this returns the result of the operation, \
1819                      without modifying the original"]
1820        #[inline]
1821        pub const fn saturating_abs(self) -> Self {
1822            if self.is_negative() {
1823                self.saturating_neg()
1824            } else {
1825                self
1826            }
1827        }
1828
1829        /// Saturating integer multiplication. Computes `self * rhs`, saturating at the
1830        /// numeric bounds instead of overflowing.
1831        ///
1832        /// # Examples
1833        ///
1834        /// ```
1835        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".saturating_mul(12), 120);")]
1836        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_mul(10), ", stringify!($SelfT), "::MAX);")]
1837        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_mul(10), ", stringify!($SelfT), "::MIN);")]
1838        /// ```
1839        #[stable(feature = "wrapping", since = "1.7.0")]
1840        #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
1841        #[must_use = "this returns the result of the operation, \
1842                      without modifying the original"]
1843        #[inline]
1844        pub const fn saturating_mul(self, rhs: Self) -> Self {
1845            match self.checked_mul(rhs) {
1846                Some(x) => x,
1847                None => if (self < 0) == (rhs < 0) {
1848                    Self::MAX
1849                } else {
1850                    Self::MIN
1851                }
1852            }
1853        }
1854
1855        /// Saturating integer division. Computes `self / rhs`, saturating at the
1856        /// numeric bounds instead of overflowing.
1857        ///
1858        /// # Panics
1859        ///
1860        /// This function will panic if `rhs` is zero.
1861        ///
1862        /// # Examples
1863        ///
1864        /// ```
1865        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".saturating_div(2), 2);")]
1866        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_div(-1), ", stringify!($SelfT), "::MIN + 1);")]
1867        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_div(-1), ", stringify!($SelfT), "::MAX);")]
1868        ///
1869        /// ```
1870        #[stable(feature = "saturating_div", since = "1.58.0")]
1871        #[rustc_const_stable(feature = "saturating_div", since = "1.58.0")]
1872        #[must_use = "this returns the result of the operation, \
1873                      without modifying the original"]
1874        #[inline]
1875        pub const fn saturating_div(self, rhs: Self) -> Self {
1876            match self.overflowing_div(rhs) {
1877                (result, false) => result,
1878                (_result, true) => Self::MAX, // MIN / -1 is the only possible saturating overflow
1879            }
1880        }
1881
1882        /// Saturating integer exponentiation. Computes `self.pow(exp)`,
1883        /// saturating at the numeric bounds instead of overflowing.
1884        ///
1885        /// # Examples
1886        ///
1887        /// ```
1888        #[doc = concat!("assert_eq!((-4", stringify!($SelfT), ").saturating_pow(3), -64);")]
1889        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_pow(2), ", stringify!($SelfT), "::MAX);")]
1890        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_pow(3), ", stringify!($SelfT), "::MIN);")]
1891        /// ```
1892        #[stable(feature = "no_panic_pow", since = "1.34.0")]
1893        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
1894        #[must_use = "this returns the result of the operation, \
1895                      without modifying the original"]
1896        #[inline]
1897        pub const fn saturating_pow(self, exp: u32) -> Self {
1898            match self.checked_pow(exp) {
1899                Some(x) => x,
1900                None if self < 0 && exp % 2 == 1 => Self::MIN,
1901                None => Self::MAX,
1902            }
1903        }
1904
1905        /// Wrapping (modular) addition. Computes `self + rhs`, wrapping around at the
1906        /// boundary of the type.
1907        ///
1908        /// # Examples
1909        ///
1910        /// ```
1911        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_add(27), 127);")]
1912        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_add(2), ", stringify!($SelfT), "::MIN + 1);")]
1913        /// ```
1914        #[stable(feature = "rust1", since = "1.0.0")]
1915        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
1916        #[must_use = "this returns the result of the operation, \
1917                      without modifying the original"]
1918        #[inline(always)]
1919        pub const fn wrapping_add(self, rhs: Self) -> Self {
1920            intrinsics::wrapping_add(self, rhs)
1921        }
1922
1923        /// Wrapping (modular) addition with an unsigned integer. Computes
1924        /// `self + rhs`, wrapping around at the boundary of the type.
1925        ///
1926        /// # Examples
1927        ///
1928        /// ```
1929        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_add_unsigned(27), 127);")]
1930        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_add_unsigned(2), ", stringify!($SelfT), "::MIN + 1);")]
1931        /// ```
1932        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1933        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1934        #[must_use = "this returns the result of the operation, \
1935                      without modifying the original"]
1936        #[inline(always)]
1937        pub const fn wrapping_add_unsigned(self, rhs: $UnsignedT) -> Self {
1938            self.wrapping_add(rhs as Self)
1939        }
1940
1941        /// Wrapping (modular) subtraction. Computes `self - rhs`, wrapping around at the
1942        /// boundary of the type.
1943        ///
1944        /// # Examples
1945        ///
1946        /// ```
1947        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".wrapping_sub(127), -127);")]
1948        #[doc = concat!("assert_eq!((-2", stringify!($SelfT), ").wrapping_sub(", stringify!($SelfT), "::MAX), ", stringify!($SelfT), "::MAX);")]
1949        /// ```
1950        #[stable(feature = "rust1", since = "1.0.0")]
1951        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
1952        #[must_use = "this returns the result of the operation, \
1953                      without modifying the original"]
1954        #[inline(always)]
1955        pub const fn wrapping_sub(self, rhs: Self) -> Self {
1956            intrinsics::wrapping_sub(self, rhs)
1957        }
1958
1959        /// Wrapping (modular) subtraction with an unsigned integer. Computes
1960        /// `self - rhs`, wrapping around at the boundary of the type.
1961        ///
1962        /// # Examples
1963        ///
1964        /// ```
1965        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".wrapping_sub_unsigned(127), -127);")]
1966        #[doc = concat!("assert_eq!((-2", stringify!($SelfT), ").wrapping_sub_unsigned(", stringify!($UnsignedT), "::MAX), -1);")]
1967        /// ```
1968        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
1969        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
1970        #[must_use = "this returns the result of the operation, \
1971                      without modifying the original"]
1972        #[inline(always)]
1973        pub const fn wrapping_sub_unsigned(self, rhs: $UnsignedT) -> Self {
1974            self.wrapping_sub(rhs as Self)
1975        }
1976
1977        /// Wrapping (modular) multiplication. Computes `self * rhs`, wrapping around at
1978        /// the boundary of the type.
1979        ///
1980        /// # Examples
1981        ///
1982        /// ```
1983        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".wrapping_mul(12), 120);")]
1984        /// assert_eq!(11i8.wrapping_mul(12), -124);
1985        /// ```
1986        #[stable(feature = "rust1", since = "1.0.0")]
1987        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
1988        #[must_use = "this returns the result of the operation, \
1989                      without modifying the original"]
1990        #[inline(always)]
1991        pub const fn wrapping_mul(self, rhs: Self) -> Self {
1992            intrinsics::wrapping_mul(self, rhs)
1993        }
1994
1995        /// Wrapping (modular) division. Computes `self / rhs`, wrapping around at the
1996        /// boundary of the type.
1997        ///
1998        /// The only case where such wrapping can occur is when one divides `MIN / -1` on a signed type (where
1999        /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value
2000        /// that is too large to represent in the type. In such a case, this function returns `MIN` itself.
2001        ///
2002        /// # Panics
2003        ///
2004        /// This function will panic if `rhs` is zero.
2005        ///
2006        /// # Examples
2007        ///
2008        /// ```
2009        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div(10), 10);")]
2010        /// assert_eq!((-128i8).wrapping_div(-1), -128);
2011        /// ```
2012        #[stable(feature = "num_wrapping", since = "1.2.0")]
2013        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2014        #[must_use = "this returns the result of the operation, \
2015                      without modifying the original"]
2016        #[inline]
2017        pub const fn wrapping_div(self, rhs: Self) -> Self {
2018            self.overflowing_div(rhs).0
2019        }
2020
2021        /// Wrapping Euclidean division. Computes `self.div_euclid(rhs)`,
2022        /// wrapping around at the boundary of the type.
2023        ///
2024        /// Wrapping will only occur in `MIN / -1` on a signed type (where `MIN` is the negative minimal value
2025        /// for the type). This is equivalent to `-MIN`, a positive value that is too large to represent in the
2026        /// type. In this case, this method returns `MIN` itself.
2027        ///
2028        /// # Panics
2029        ///
2030        /// This function will panic if `rhs` is zero.
2031        ///
2032        /// # Examples
2033        ///
2034        /// ```
2035        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div_euclid(10), 10);")]
2036        /// assert_eq!((-128i8).wrapping_div_euclid(-1), -128);
2037        /// ```
2038        #[stable(feature = "euclidean_division", since = "1.38.0")]
2039        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2040        #[must_use = "this returns the result of the operation, \
2041                      without modifying the original"]
2042        #[inline]
2043        pub const fn wrapping_div_euclid(self, rhs: Self) -> Self {
2044            self.overflowing_div_euclid(rhs).0
2045        }
2046
2047        /// Wrapping (modular) remainder. Computes `self % rhs`, wrapping around at the
2048        /// boundary of the type.
2049        ///
2050        /// Such wrap-around never actually occurs mathematically; implementation artifacts make `x % y`
2051        /// invalid for `MIN / -1` on a signed type (where `MIN` is the negative minimal value). In such a case,
2052        /// this function returns `0`.
2053        ///
2054        /// # Panics
2055        ///
2056        /// This function will panic if `rhs` is zero.
2057        ///
2058        /// # Examples
2059        ///
2060        /// ```
2061        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem(10), 0);")]
2062        /// assert_eq!((-128i8).wrapping_rem(-1), 0);
2063        /// ```
2064        #[stable(feature = "num_wrapping", since = "1.2.0")]
2065        #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")]
2066        #[must_use = "this returns the result of the operation, \
2067                      without modifying the original"]
2068        #[inline]
2069        pub const fn wrapping_rem(self, rhs: Self) -> Self {
2070            self.overflowing_rem(rhs).0
2071        }
2072
2073        /// Wrapping Euclidean remainder. Computes `self.rem_euclid(rhs)`, wrapping around
2074        /// at the boundary of the type.
2075        ///
2076        /// Wrapping will only occur in `MIN % -1` on a signed type (where `MIN` is the negative minimal value
2077        /// for the type). In this case, this method returns 0.
2078        ///
2079        /// # Panics
2080        ///
2081        /// This function will panic if `rhs` is zero.
2082        ///
2083        /// # Examples
2084        ///
2085        /// ```
2086        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem_euclid(10), 0);")]
2087        /// assert_eq!((-128i8).wrapping_rem_euclid(-1), 0);
2088        /// ```
2089        #[stable(feature = "euclidean_division", since = "1.38.0")]
2090        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2091        #[must_use = "this returns the result of the operation, \
2092                      without modifying the original"]
2093        #[inline]
2094        pub const fn wrapping_rem_euclid(self, rhs: Self) -> Self {
2095            self.overflowing_rem_euclid(rhs).0
2096        }
2097
2098        /// Wrapping (modular) negation. Computes `-self`, wrapping around at the boundary
2099        /// of the type.
2100        ///
2101        /// The only case where such wrapping can occur is when one negates `MIN` on a signed type (where `MIN`
2102        /// is the negative minimal value for the type); this is a positive value that is too large to represent
2103        /// in the type. In such a case, this function returns `MIN` itself.
2104        ///
2105        /// # Examples
2106        ///
2107        /// ```
2108        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_neg(), -100);")]
2109        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").wrapping_neg(), 100);")]
2110        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.wrapping_neg(), ", stringify!($SelfT), "::MIN);")]
2111        /// ```
2112        #[stable(feature = "num_wrapping", since = "1.2.0")]
2113        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2114        #[must_use = "this returns the result of the operation, \
2115                      without modifying the original"]
2116        #[inline(always)]
2117        pub const fn wrapping_neg(self) -> Self {
2118            (0 as $SelfT).wrapping_sub(self)
2119        }
2120
2121        /// Panic-free bitwise shift-left; yields `self << mask(rhs)`, where `mask` removes
2122        /// any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type.
2123        ///
2124        /// Note that this is *not* the same as a rotate-left; the RHS of a wrapping shift-left is restricted to
2125        /// the range of the type, rather than the bits shifted out of the LHS being returned to the other end.
2126        /// The primitive integer types all implement a [`rotate_left`](Self::rotate_left) function,
2127        /// which may be what you want instead.
2128        ///
2129        /// # Examples
2130        ///
2131        /// ```
2132        #[doc = concat!("assert_eq!((-1", stringify!($SelfT), ").wrapping_shl(7), -128);")]
2133        #[doc = concat!("assert_eq!((-1", stringify!($SelfT), ").wrapping_shl(128), -1);")]
2134        /// ```
2135        #[stable(feature = "num_wrapping", since = "1.2.0")]
2136        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2137        #[must_use = "this returns the result of the operation, \
2138                      without modifying the original"]
2139        #[inline(always)]
2140        pub const fn wrapping_shl(self, rhs: u32) -> Self {
2141            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2142            // out of bounds
2143            unsafe {
2144                self.unchecked_shl(rhs & (Self::BITS - 1))
2145            }
2146        }
2147
2148        /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`, where `mask`
2149        /// removes any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type.
2150        ///
2151        /// Note that this is *not* the same as a rotate-right; the RHS of a wrapping shift-right is restricted
2152        /// to the range of the type, rather than the bits shifted out of the LHS being returned to the other
2153        /// end. The primitive integer types all implement a [`rotate_right`](Self::rotate_right) function,
2154        /// which may be what you want instead.
2155        ///
2156        /// # Examples
2157        ///
2158        /// ```
2159        #[doc = concat!("assert_eq!((-128", stringify!($SelfT), ").wrapping_shr(7), -1);")]
2160        /// assert_eq!((-128i16).wrapping_shr(64), -128);
2161        /// ```
2162        #[stable(feature = "num_wrapping", since = "1.2.0")]
2163        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2164        #[must_use = "this returns the result of the operation, \
2165                      without modifying the original"]
2166        #[inline(always)]
2167        pub const fn wrapping_shr(self, rhs: u32) -> Self {
2168            // SAFETY: the masking by the bitsize of the type ensures that we do not shift
2169            // out of bounds
2170            unsafe {
2171                self.unchecked_shr(rhs & (Self::BITS - 1))
2172            }
2173        }
2174
2175        /// Wrapping (modular) absolute value. Computes `self.abs()`, wrapping around at
2176        /// the boundary of the type.
2177        ///
2178        /// The only case where such wrapping can occur is when one takes the absolute value of the negative
2179        /// minimal value for the type; this is a positive value that is too large to represent in the type. In
2180        /// such a case, this function returns `MIN` itself.
2181        ///
2182        /// # Examples
2183        ///
2184        /// ```
2185        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_abs(), 100);")]
2186        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").wrapping_abs(), 100);")]
2187        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.wrapping_abs(), ", stringify!($SelfT), "::MIN);")]
2188        /// assert_eq!((-128i8).wrapping_abs() as u8, 128);
2189        /// ```
2190        #[stable(feature = "no_panic_abs", since = "1.13.0")]
2191        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2192        #[must_use = "this returns the result of the operation, \
2193                      without modifying the original"]
2194        #[allow(unused_attributes)]
2195        #[inline]
2196        pub const fn wrapping_abs(self) -> Self {
2197             if self.is_negative() {
2198                 self.wrapping_neg()
2199             } else {
2200                 self
2201             }
2202        }
2203
2204        /// Computes the absolute value of `self` without any wrapping
2205        /// or panicking.
2206        ///
2207        ///
2208        /// # Examples
2209        ///
2210        /// ```
2211        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".unsigned_abs(), 100", stringify!($UnsignedT), ");")]
2212        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").unsigned_abs(), 100", stringify!($UnsignedT), ");")]
2213        /// assert_eq!((-128i8).unsigned_abs(), 128u8);
2214        /// ```
2215        #[stable(feature = "unsigned_abs", since = "1.51.0")]
2216        #[rustc_const_stable(feature = "unsigned_abs", since = "1.51.0")]
2217        #[must_use = "this returns the result of the operation, \
2218                      without modifying the original"]
2219        #[inline]
2220        pub const fn unsigned_abs(self) -> $UnsignedT {
2221             self.wrapping_abs() as $UnsignedT
2222        }
2223
2224        /// Wrapping (modular) exponentiation. Computes `self.pow(exp)`,
2225        /// wrapping around at the boundary of the type.
2226        ///
2227        /// # Examples
2228        ///
2229        /// ```
2230        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_pow(4), 81);")]
2231        /// assert_eq!(3i8.wrapping_pow(5), -13);
2232        /// assert_eq!(3i8.wrapping_pow(6), -39);
2233        /// ```
2234        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2235        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2236        #[must_use = "this returns the result of the operation, \
2237                      without modifying the original"]
2238        #[inline]
2239        pub const fn wrapping_pow(self, mut exp: u32) -> Self {
2240            if exp == 0 {
2241                return 1;
2242            }
2243            let mut base = self;
2244            let mut acc: Self = 1;
2245
2246            if intrinsics::is_val_statically_known(exp) {
2247                while exp > 1 {
2248                    if (exp & 1) == 1 {
2249                        acc = acc.wrapping_mul(base);
2250                    }
2251                    exp /= 2;
2252                    base = base.wrapping_mul(base);
2253                }
2254
2255                // since exp!=0, finally the exp must be 1.
2256                // Deal with the final bit of the exponent separately, since
2257                // squaring the base afterwards is not necessary.
2258                acc.wrapping_mul(base)
2259            } else {
2260                // This is faster than the above when the exponent is not known
2261                // at compile time. We can't use the same code for the constant
2262                // exponent case because LLVM is currently unable to unroll
2263                // this loop.
2264                loop {
2265                    if (exp & 1) == 1 {
2266                        acc = acc.wrapping_mul(base);
2267                        // since exp!=0, finally the exp must be 1.
2268                        if exp == 1 {
2269                            return acc;
2270                        }
2271                    }
2272                    exp /= 2;
2273                    base = base.wrapping_mul(base);
2274                }
2275            }
2276        }
2277
2278        /// Calculates `self` + `rhs`.
2279        ///
2280        /// Returns a tuple of the addition along with a boolean indicating
2281        /// whether an arithmetic overflow would occur. If an overflow would have
2282        /// occurred then the wrapped value is returned.
2283        ///
2284        /// # Examples
2285        ///
2286        /// ```
2287        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_add(2), (7, false));")]
2288        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.overflowing_add(1), (", stringify!($SelfT), "::MIN, true));")]
2289        /// ```
2290        #[stable(feature = "wrapping", since = "1.7.0")]
2291        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2292        #[must_use = "this returns the result of the operation, \
2293                      without modifying the original"]
2294        #[inline(always)]
2295        pub const fn overflowing_add(self, rhs: Self) -> (Self, bool) {
2296            let (a, b) = intrinsics::add_with_overflow(self as $ActualT, rhs as $ActualT);
2297            (a as Self, b)
2298        }
2299
2300        /// Calculates `self` + `rhs` + `carry` and checks for overflow.
2301        ///
2302        /// Performs "ternary addition" of two integer operands and a carry-in
2303        /// bit, and returns a tuple of the sum along with a boolean indicating
2304        /// whether an arithmetic overflow would occur. On overflow, the wrapped
2305        /// value is returned.
2306        ///
2307        /// This allows chaining together multiple additions to create a wider
2308        /// addition, and can be useful for bignum addition. This method should
2309        /// only be used for the most significant word; for the less significant
2310        /// words the unsigned method
2311        #[doc = concat!("[`", stringify!($UnsignedT), "::carrying_add`]")]
2312        /// should be used.
2313        ///
2314        /// The output boolean returned by this method is *not* a carry flag,
2315        /// and should *not* be added to a more significant word.
2316        ///
2317        /// If the input carry is false, this method is equivalent to
2318        /// [`overflowing_add`](Self::overflowing_add).
2319        ///
2320        /// # Examples
2321        ///
2322        /// ```
2323        /// #![feature(bigint_helper_methods)]
2324        /// // Only the most significant word is signed.
2325        /// //
2326        #[doc = concat!("//   10  MAX    (a = 10 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2327        #[doc = concat!("// + -5    9    (b = -5 × 2^", stringify!($BITS), " + 9)")]
2328        /// // ---------
2329        #[doc = concat!("//    6    8    (sum = 6 × 2^", stringify!($BITS), " + 8)")]
2330        ///
2331        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (10, ", stringify!($UnsignedT), "::MAX);")]
2332        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (-5, 9);")]
2333        /// let carry0 = false;
2334        ///
2335        #[doc = concat!("// ", stringify!($UnsignedT), "::carrying_add for the less significant words")]
2336        /// let (sum0, carry1) = a0.carrying_add(b0, carry0);
2337        /// assert_eq!(carry1, true);
2338        ///
2339        #[doc = concat!("// ", stringify!($SelfT), "::carrying_add for the most significant word")]
2340        /// let (sum1, overflow) = a1.carrying_add(b1, carry1);
2341        /// assert_eq!(overflow, false);
2342        ///
2343        /// assert_eq!((sum1, sum0), (6, 8));
2344        /// ```
2345        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2346        #[must_use = "this returns the result of the operation, \
2347                      without modifying the original"]
2348        #[inline]
2349        pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) {
2350            // note: longer-term this should be done via an intrinsic.
2351            // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946).
2352            let (a, b) = self.overflowing_add(rhs);
2353            let (c, d) = a.overflowing_add(carry as $SelfT);
2354            (c, b != d)
2355        }
2356
2357        /// Calculates `self` + `rhs` with an unsigned `rhs`.
2358        ///
2359        /// Returns a tuple of the addition along with a boolean indicating
2360        /// whether an arithmetic overflow would occur. If an overflow would
2361        /// have occurred then the wrapped value is returned.
2362        ///
2363        /// # Examples
2364        ///
2365        /// ```
2366        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_unsigned(2), (3, false));")]
2367        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN).overflowing_add_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MAX, false));")]
2368        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_unsigned(3), (", stringify!($SelfT), "::MIN, true));")]
2369        /// ```
2370        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2371        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2372        #[must_use = "this returns the result of the operation, \
2373                      without modifying the original"]
2374        #[inline]
2375        pub const fn overflowing_add_unsigned(self, rhs: $UnsignedT) -> (Self, bool) {
2376            let rhs = rhs as Self;
2377            let (res, overflowed) = self.overflowing_add(rhs);
2378            (res, overflowed ^ (rhs < 0))
2379        }
2380
2381        /// Calculates `self` - `rhs`.
2382        ///
2383        /// Returns a tuple of the subtraction along with a boolean indicating whether an arithmetic overflow
2384        /// would occur. If an overflow would have occurred then the wrapped value is returned.
2385        ///
2386        /// # Examples
2387        ///
2388        /// ```
2389        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_sub(2), (3, false));")]
2390        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_sub(1), (", stringify!($SelfT), "::MAX, true));")]
2391        /// ```
2392        #[stable(feature = "wrapping", since = "1.7.0")]
2393        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2394        #[must_use = "this returns the result of the operation, \
2395                      without modifying the original"]
2396        #[inline(always)]
2397        pub const fn overflowing_sub(self, rhs: Self) -> (Self, bool) {
2398            let (a, b) = intrinsics::sub_with_overflow(self as $ActualT, rhs as $ActualT);
2399            (a as Self, b)
2400        }
2401
2402        /// Calculates `self` &minus; `rhs` &minus; `borrow` and checks for
2403        /// overflow.
2404        ///
2405        /// Performs "ternary subtraction" by subtracting both an integer
2406        /// operand and a borrow-in bit from `self`, and returns a tuple of the
2407        /// difference along with a boolean indicating whether an arithmetic
2408        /// overflow would occur. On overflow, the wrapped value is returned.
2409        ///
2410        /// This allows chaining together multiple subtractions to create a
2411        /// wider subtraction, and can be useful for bignum subtraction. This
2412        /// method should only be used for the most significant word; for the
2413        /// less significant words the unsigned method
2414        #[doc = concat!("[`", stringify!($UnsignedT), "::borrowing_sub`]")]
2415        /// should be used.
2416        ///
2417        /// The output boolean returned by this method is *not* a borrow flag,
2418        /// and should *not* be subtracted from a more significant word.
2419        ///
2420        /// If the input borrow is false, this method is equivalent to
2421        /// [`overflowing_sub`](Self::overflowing_sub).
2422        ///
2423        /// # Examples
2424        ///
2425        /// ```
2426        /// #![feature(bigint_helper_methods)]
2427        /// // Only the most significant word is signed.
2428        /// //
2429        #[doc = concat!("//    6    8    (a = 6 × 2^", stringify!($BITS), " + 8)")]
2430        #[doc = concat!("// - -5    9    (b = -5 × 2^", stringify!($BITS), " + 9)")]
2431        /// // ---------
2432        #[doc = concat!("//   10  MAX    (diff = 10 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")]
2433        ///
2434        #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (6, 8);")]
2435        #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (-5, 9);")]
2436        /// let borrow0 = false;
2437        ///
2438        #[doc = concat!("// ", stringify!($UnsignedT), "::borrowing_sub for the less significant words")]
2439        /// let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0);
2440        /// assert_eq!(borrow1, true);
2441        ///
2442        #[doc = concat!("// ", stringify!($SelfT), "::borrowing_sub for the most significant word")]
2443        /// let (diff1, overflow) = a1.borrowing_sub(b1, borrow1);
2444        /// assert_eq!(overflow, false);
2445        ///
2446        #[doc = concat!("assert_eq!((diff1, diff0), (10, ", stringify!($UnsignedT), "::MAX));")]
2447        /// ```
2448        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2449        #[must_use = "this returns the result of the operation, \
2450                      without modifying the original"]
2451        #[inline]
2452        pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) {
2453            // note: longer-term this should be done via an intrinsic.
2454            // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946).
2455            let (a, b) = self.overflowing_sub(rhs);
2456            let (c, d) = a.overflowing_sub(borrow as $SelfT);
2457            (c, b != d)
2458        }
2459
2460        /// Calculates `self` - `rhs` with an unsigned `rhs`.
2461        ///
2462        /// Returns a tuple of the subtraction along with a boolean indicating
2463        /// whether an arithmetic overflow would occur. If an overflow would
2464        /// have occurred then the wrapped value is returned.
2465        ///
2466        /// # Examples
2467        ///
2468        /// ```
2469        #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_unsigned(2), (-1, false));")]
2470        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).overflowing_sub_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MIN, false));")]
2471        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).overflowing_sub_unsigned(3), (", stringify!($SelfT), "::MAX, true));")]
2472        /// ```
2473        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
2474        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
2475        #[must_use = "this returns the result of the operation, \
2476                      without modifying the original"]
2477        #[inline]
2478        pub const fn overflowing_sub_unsigned(self, rhs: $UnsignedT) -> (Self, bool) {
2479            let rhs = rhs as Self;
2480            let (res, overflowed) = self.overflowing_sub(rhs);
2481            (res, overflowed ^ (rhs < 0))
2482        }
2483
2484        /// Calculates the multiplication of `self` and `rhs`.
2485        ///
2486        /// Returns a tuple of the multiplication along with a boolean indicating whether an arithmetic overflow
2487        /// would occur. If an overflow would have occurred then the wrapped value is returned.
2488        ///
2489        /// # Examples
2490        ///
2491        /// ```
2492        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_mul(2), (10, false));")]
2493        /// assert_eq!(1_000_000_000i32.overflowing_mul(10), (1410065408, true));
2494        /// ```
2495        #[stable(feature = "wrapping", since = "1.7.0")]
2496        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2497        #[must_use = "this returns the result of the operation, \
2498                      without modifying the original"]
2499        #[inline(always)]
2500        pub const fn overflowing_mul(self, rhs: Self) -> (Self, bool) {
2501            let (a, b) = intrinsics::mul_with_overflow(self as $ActualT, rhs as $ActualT);
2502            (a as Self, b)
2503        }
2504
2505        /// Calculates the complete product `self * rhs` without the possibility to overflow.
2506        ///
2507        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2508        /// of the result as two separate values, in that order.
2509        ///
2510        /// If you also need to add a carry to the wide result, then you want
2511        /// [`Self::carrying_mul`] instead.
2512        ///
2513        /// # Examples
2514        ///
2515        /// Please note that this example is shared between integer types.
2516        /// Which explains why `i32` is used here.
2517        ///
2518        /// ```
2519        /// #![feature(bigint_helper_methods)]
2520        /// assert_eq!(5i32.widening_mul(-2), (4294967286, -1));
2521        /// assert_eq!(1_000_000_000i32.widening_mul(-10), (2884901888, -3));
2522        /// ```
2523        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2524        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2525        #[must_use = "this returns the result of the operation, \
2526                      without modifying the original"]
2527        #[inline]
2528        pub const fn widening_mul(self, rhs: Self) -> ($UnsignedT, Self) {
2529            Self::carrying_mul_add(self, rhs, 0, 0)
2530        }
2531
2532        /// Calculates the "full multiplication" `self * rhs + carry`
2533        /// without the possibility to overflow.
2534        ///
2535        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2536        /// of the result as two separate values, in that order.
2537        ///
2538        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2539        /// additional amount of overflow. This allows for chaining together multiple
2540        /// multiplications to create "big integers" which represent larger values.
2541        ///
2542        /// If you don't need the `carry`, then you can use [`Self::widening_mul`] instead.
2543        ///
2544        /// # Examples
2545        ///
2546        /// Please note that this example is shared between integer types.
2547        /// Which explains why `i32` is used here.
2548        ///
2549        /// ```
2550        /// #![feature(bigint_helper_methods)]
2551        /// assert_eq!(5i32.carrying_mul(-2, 0), (4294967286, -1));
2552        /// assert_eq!(5i32.carrying_mul(-2, 10), (0, 0));
2553        /// assert_eq!(1_000_000_000i32.carrying_mul(-10, 0), (2884901888, -3));
2554        /// assert_eq!(1_000_000_000i32.carrying_mul(-10, 10), (2884901898, -3));
2555        #[doc = concat!("assert_eq!(",
2556            stringify!($SelfT), "::MAX.carrying_mul(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2557            "(", stringify!($SelfT), "::MAX.unsigned_abs() + 1, ", stringify!($SelfT), "::MAX / 2));"
2558        )]
2559        /// ```
2560        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2561        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2562        #[must_use = "this returns the result of the operation, \
2563                      without modifying the original"]
2564        #[inline]
2565        pub const fn carrying_mul(self, rhs: Self, carry: Self) -> ($UnsignedT, Self) {
2566            Self::carrying_mul_add(self, rhs, carry, 0)
2567        }
2568
2569        /// Calculates the "full multiplication" `self * rhs + carry1 + carry2`
2570        /// without the possibility to overflow.
2571        ///
2572        /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
2573        /// of the result as two separate values, in that order.
2574        ///
2575        /// Performs "long multiplication" which takes in an extra amount to add, and may return an
2576        /// additional amount of overflow. This allows for chaining together multiple
2577        /// multiplications to create "big integers" which represent larger values.
2578        ///
2579        /// If you don't need either `carry`, then you can use [`Self::widening_mul`] instead,
2580        /// and if you only need one `carry`, then you can use [`Self::carrying_mul`] instead.
2581        ///
2582        /// # Examples
2583        ///
2584        /// Please note that this example is shared between integer types.
2585        /// Which explains why `i32` is used here.
2586        ///
2587        /// ```
2588        /// #![feature(bigint_helper_methods)]
2589        /// assert_eq!(5i32.carrying_mul_add(-2, 0, 0), (4294967286, -1));
2590        /// assert_eq!(5i32.carrying_mul_add(-2, 10, 10), (10, 0));
2591        /// assert_eq!(1_000_000_000i32.carrying_mul_add(-10, 0, 0), (2884901888, -3));
2592        /// assert_eq!(1_000_000_000i32.carrying_mul_add(-10, 10, 10), (2884901908, -3));
2593        #[doc = concat!("assert_eq!(",
2594            stringify!($SelfT), "::MAX.carrying_mul_add(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
2595            "(", stringify!($UnsignedT), "::MAX, ", stringify!($SelfT), "::MAX / 2));"
2596        )]
2597        /// ```
2598        #[unstable(feature = "bigint_helper_methods", issue = "85532")]
2599        #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
2600        #[must_use = "this returns the result of the operation, \
2601                      without modifying the original"]
2602        #[inline]
2603        pub const fn carrying_mul_add(self, rhs: Self, carry: Self, add: Self) -> ($UnsignedT, Self) {
2604            intrinsics::carrying_mul_add(self, rhs, carry, add)
2605        }
2606
2607        /// Calculates the divisor when `self` is divided by `rhs`.
2608        ///
2609        /// Returns a tuple of the divisor along with a boolean indicating whether an arithmetic overflow would
2610        /// occur. If an overflow would occur then self is returned.
2611        ///
2612        /// # Panics
2613        ///
2614        /// This function will panic if `rhs` is zero.
2615        ///
2616        /// # Examples
2617        ///
2618        /// ```
2619        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div(2), (2, false));")]
2620        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_div(-1), (", stringify!($SelfT), "::MIN, true));")]
2621        /// ```
2622        #[inline]
2623        #[stable(feature = "wrapping", since = "1.7.0")]
2624        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2625        #[must_use = "this returns the result of the operation, \
2626                      without modifying the original"]
2627        pub const fn overflowing_div(self, rhs: Self) -> (Self, bool) {
2628            // Using `&` helps LLVM see that it is the same check made in division.
2629            if intrinsics::unlikely((self == Self::MIN) & (rhs == -1)) {
2630                (self, true)
2631            } else {
2632                (self / rhs, false)
2633            }
2634        }
2635
2636        /// Calculates the quotient of Euclidean division `self.div_euclid(rhs)`.
2637        ///
2638        /// Returns a tuple of the divisor along with a boolean indicating whether an arithmetic overflow would
2639        /// occur. If an overflow would occur then `self` is returned.
2640        ///
2641        /// # Panics
2642        ///
2643        /// This function will panic if `rhs` is zero.
2644        ///
2645        /// # Examples
2646        ///
2647        /// ```
2648        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));")]
2649        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_div_euclid(-1), (", stringify!($SelfT), "::MIN, true));")]
2650        /// ```
2651        #[inline]
2652        #[stable(feature = "euclidean_division", since = "1.38.0")]
2653        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2654        #[must_use = "this returns the result of the operation, \
2655                      without modifying the original"]
2656        pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) {
2657            // Using `&` helps LLVM see that it is the same check made in division.
2658            if intrinsics::unlikely((self == Self::MIN) & (rhs == -1)) {
2659                (self, true)
2660            } else {
2661                (self.div_euclid(rhs), false)
2662            }
2663        }
2664
2665        /// Calculates the remainder when `self` is divided by `rhs`.
2666        ///
2667        /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an
2668        /// arithmetic overflow would occur. If an overflow would occur then 0 is returned.
2669        ///
2670        /// # Panics
2671        ///
2672        /// This function will panic if `rhs` is zero.
2673        ///
2674        /// # Examples
2675        ///
2676        /// ```
2677        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")]
2678        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_rem(-1), (0, true));")]
2679        /// ```
2680        #[inline]
2681        #[stable(feature = "wrapping", since = "1.7.0")]
2682        #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")]
2683        #[must_use = "this returns the result of the operation, \
2684                      without modifying the original"]
2685        pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) {
2686            if intrinsics::unlikely(rhs == -1) {
2687                (0, self == Self::MIN)
2688            } else {
2689                (self % rhs, false)
2690            }
2691        }
2692
2693
2694        /// Overflowing Euclidean remainder. Calculates `self.rem_euclid(rhs)`.
2695        ///
2696        /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an
2697        /// arithmetic overflow would occur. If an overflow would occur then 0 is returned.
2698        ///
2699        /// # Panics
2700        ///
2701        /// This function will panic if `rhs` is zero.
2702        ///
2703        /// # Examples
2704        ///
2705        /// ```
2706        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")]
2707        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_rem_euclid(-1), (0, true));")]
2708        /// ```
2709        #[stable(feature = "euclidean_division", since = "1.38.0")]
2710        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2711        #[must_use = "this returns the result of the operation, \
2712                      without modifying the original"]
2713        #[inline]
2714        #[track_caller]
2715        pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) {
2716            if intrinsics::unlikely(rhs == -1) {
2717                (0, self == Self::MIN)
2718            } else {
2719                (self.rem_euclid(rhs), false)
2720            }
2721        }
2722
2723
2724        /// Negates self, overflowing if this is equal to the minimum value.
2725        ///
2726        /// Returns a tuple of the negated version of self along with a boolean indicating whether an overflow
2727        /// happened. If `self` is the minimum value (e.g., `i32::MIN` for values of type `i32`), then the
2728        /// minimum value will be returned again and `true` will be returned for an overflow happening.
2729        ///
2730        /// # Examples
2731        ///
2732        /// ```
2733        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".overflowing_neg(), (-2, false));")]
2734        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_neg(), (", stringify!($SelfT), "::MIN, true));")]
2735        /// ```
2736        #[inline]
2737        #[stable(feature = "wrapping", since = "1.7.0")]
2738        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2739        #[must_use = "this returns the result of the operation, \
2740                      without modifying the original"]
2741        #[allow(unused_attributes)]
2742        pub const fn overflowing_neg(self) -> (Self, bool) {
2743            if intrinsics::unlikely(self == Self::MIN) {
2744                (Self::MIN, true)
2745            } else {
2746                (-self, false)
2747            }
2748        }
2749
2750        /// Shifts self left by `rhs` bits.
2751        ///
2752        /// Returns a tuple of the shifted version of self along with a boolean indicating whether the shift
2753        /// value was larger than or equal to the number of bits. If the shift value is too large, then value is
2754        /// masked (N-1) where N is the number of bits, and this value is then used to perform the shift.
2755        ///
2756        /// # Examples
2757        ///
2758        /// ```
2759        #[doc = concat!("assert_eq!(0x1", stringify!($SelfT),".overflowing_shl(4), (0x10, false));")]
2760        /// assert_eq!(0x1i32.overflowing_shl(36), (0x10, true));
2761        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shl(", stringify!($BITS_MINUS_ONE), "), (0, false));")]
2762        /// ```
2763        #[stable(feature = "wrapping", since = "1.7.0")]
2764        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2765        #[must_use = "this returns the result of the operation, \
2766                      without modifying the original"]
2767        #[inline]
2768        pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) {
2769            (self.wrapping_shl(rhs), rhs >= Self::BITS)
2770        }
2771
2772        /// Shifts self right by `rhs` bits.
2773        ///
2774        /// Returns a tuple of the shifted version of self along with a boolean indicating whether the shift
2775        /// value was larger than or equal to the number of bits. If the shift value is too large, then value is
2776        /// masked (N-1) where N is the number of bits, and this value is then used to perform the shift.
2777        ///
2778        /// # Examples
2779        ///
2780        /// ```
2781        #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(4), (0x1, false));")]
2782        /// assert_eq!(0x10i32.overflowing_shr(36), (0x1, true));
2783        /// ```
2784        #[stable(feature = "wrapping", since = "1.7.0")]
2785        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2786        #[must_use = "this returns the result of the operation, \
2787                      without modifying the original"]
2788        #[inline]
2789        pub const fn overflowing_shr(self, rhs: u32) -> (Self, bool) {
2790            (self.wrapping_shr(rhs), rhs >= Self::BITS)
2791        }
2792
2793        /// Computes the absolute value of `self`.
2794        ///
2795        /// Returns a tuple of the absolute version of self along with a boolean indicating whether an overflow
2796        /// happened. If self is the minimum value
2797        #[doc = concat!("(e.g., ", stringify!($SelfT), "::MIN for values of type ", stringify!($SelfT), "),")]
2798        /// then the minimum value will be returned again and true will be returned
2799        /// for an overflow happening.
2800        ///
2801        /// # Examples
2802        ///
2803        /// ```
2804        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".overflowing_abs(), (10, false));")]
2805        #[doc = concat!("assert_eq!((-10", stringify!($SelfT), ").overflowing_abs(), (10, false));")]
2806        #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN).overflowing_abs(), (", stringify!($SelfT), "::MIN, true));")]
2807        /// ```
2808        #[stable(feature = "no_panic_abs", since = "1.13.0")]
2809        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
2810        #[must_use = "this returns the result of the operation, \
2811                      without modifying the original"]
2812        #[inline]
2813        pub const fn overflowing_abs(self) -> (Self, bool) {
2814            (self.wrapping_abs(), self == Self::MIN)
2815        }
2816
2817        /// Raises self to the power of `exp`, using exponentiation by squaring.
2818        ///
2819        /// Returns a tuple of the exponentiation along with a bool indicating
2820        /// whether an overflow happened.
2821        ///
2822        /// # Examples
2823        ///
2824        /// ```
2825        #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".overflowing_pow(4), (81, false));")]
2826        /// assert_eq!(3i8.overflowing_pow(5), (-13, true));
2827        /// ```
2828        #[stable(feature = "no_panic_pow", since = "1.34.0")]
2829        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2830        #[must_use = "this returns the result of the operation, \
2831                      without modifying the original"]
2832        #[inline]
2833        pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) {
2834            if exp == 0 {
2835                return (1,false);
2836            }
2837            let mut base = self;
2838            let mut acc: Self = 1;
2839            let mut overflown = false;
2840            // Scratch space for storing results of overflowing_mul.
2841            let mut r;
2842
2843            loop {
2844                if (exp & 1) == 1 {
2845                    r = acc.overflowing_mul(base);
2846                    // since exp!=0, finally the exp must be 1.
2847                    if exp == 1 {
2848                        r.1 |= overflown;
2849                        return r;
2850                    }
2851                    acc = r.0;
2852                    overflown |= r.1;
2853                }
2854                exp /= 2;
2855                r = base.overflowing_mul(base);
2856                base = r.0;
2857                overflown |= r.1;
2858            }
2859        }
2860
2861        /// Raises self to the power of `exp`, using exponentiation by squaring.
2862        ///
2863        /// # Examples
2864        ///
2865        /// ```
2866        #[doc = concat!("let x: ", stringify!($SelfT), " = 2; // or any other integer type")]
2867        ///
2868        /// assert_eq!(x.pow(5), 32);
2869        /// ```
2870        #[stable(feature = "rust1", since = "1.0.0")]
2871        #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")]
2872        #[must_use = "this returns the result of the operation, \
2873                      without modifying the original"]
2874        #[inline]
2875        #[rustc_inherit_overflow_checks]
2876        pub const fn pow(self, mut exp: u32) -> Self {
2877            if exp == 0 {
2878                return 1;
2879            }
2880            let mut base = self;
2881            let mut acc = 1;
2882
2883            if intrinsics::is_val_statically_known(exp) {
2884                while exp > 1 {
2885                    if (exp & 1) == 1 {
2886                        acc = acc * base;
2887                    }
2888                    exp /= 2;
2889                    base = base * base;
2890                }
2891
2892                // since exp!=0, finally the exp must be 1.
2893                // Deal with the final bit of the exponent separately, since
2894                // squaring the base afterwards is not necessary and may cause a
2895                // needless overflow.
2896                acc * base
2897            } else {
2898                // This is faster than the above when the exponent is not known
2899                // at compile time. We can't use the same code for the constant
2900                // exponent case because LLVM is currently unable to unroll
2901                // this loop.
2902                loop {
2903                    if (exp & 1) == 1 {
2904                        acc = acc * base;
2905                        // since exp!=0, finally the exp must be 1.
2906                        if exp == 1 {
2907                            return acc;
2908                        }
2909                    }
2910                    exp /= 2;
2911                    base = base * base;
2912                }
2913            }
2914        }
2915
2916        /// Returns the square root of the number, rounded down.
2917        ///
2918        /// # Panics
2919        ///
2920        /// This function will panic if `self` is negative.
2921        ///
2922        /// # Examples
2923        ///
2924        /// ```
2925        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".isqrt(), 3);")]
2926        /// ```
2927        #[stable(feature = "isqrt", since = "1.84.0")]
2928        #[rustc_const_stable(feature = "isqrt", since = "1.84.0")]
2929        #[must_use = "this returns the result of the operation, \
2930                      without modifying the original"]
2931        #[inline]
2932        #[track_caller]
2933        pub const fn isqrt(self) -> Self {
2934            match self.checked_isqrt() {
2935                Some(sqrt) => sqrt,
2936                None => crate::num::int_sqrt::panic_for_negative_argument(),
2937            }
2938        }
2939
2940        /// Calculates the quotient of Euclidean division of `self` by `rhs`.
2941        ///
2942        /// This computes the integer `q` such that `self = q * rhs + r`, with
2943        /// `r = self.rem_euclid(rhs)` and `0 <= r < abs(rhs)`.
2944        ///
2945        /// In other words, the result is `self / rhs` rounded to the integer `q`
2946        /// such that `self >= q * rhs`.
2947        /// If `self > 0`, this is equal to rounding towards zero (the default in Rust);
2948        /// if `self < 0`, this is equal to rounding away from zero (towards +/- infinity).
2949        /// If `rhs > 0`, this is equal to rounding towards -infinity;
2950        /// if `rhs < 0`, this is equal to rounding towards +infinity.
2951        ///
2952        /// # Panics
2953        ///
2954        /// This function will panic if `rhs` is zero or if `self` is `Self::MIN`
2955        /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag.
2956        ///
2957        /// # Examples
2958        ///
2959        /// ```
2960        #[doc = concat!("let a: ", stringify!($SelfT), " = 7; // or any other integer type")]
2961        /// let b = 4;
2962        ///
2963        /// assert_eq!(a.div_euclid(b), 1); // 7 >= 4 * 1
2964        /// assert_eq!(a.div_euclid(-b), -1); // 7 >= -4 * -1
2965        /// assert_eq!((-a).div_euclid(b), -2); // -7 >= 4 * -2
2966        /// assert_eq!((-a).div_euclid(-b), 2); // -7 >= -4 * 2
2967        /// ```
2968        #[stable(feature = "euclidean_division", since = "1.38.0")]
2969        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
2970        #[must_use = "this returns the result of the operation, \
2971                      without modifying the original"]
2972        #[inline]
2973        #[track_caller]
2974        pub const fn div_euclid(self, rhs: Self) -> Self {
2975            let q = self / rhs;
2976            if self % rhs < 0 {
2977                return if rhs > 0 { q - 1 } else { q + 1 }
2978            }
2979            q
2980        }
2981
2982
2983        /// Calculates the least nonnegative remainder of `self (mod rhs)`.
2984        ///
2985        /// This is done as if by the Euclidean division algorithm -- given
2986        /// `r = self.rem_euclid(rhs)`, the result satisfies
2987        /// `self = rhs * self.div_euclid(rhs) + r` and `0 <= r < abs(rhs)`.
2988        ///
2989        /// # Panics
2990        ///
2991        /// This function will panic if `rhs` is zero or if `self` is `Self::MIN` and
2992        /// `rhs` is -1. This behavior is not affected by the `overflow-checks` flag.
2993        ///
2994        /// # Examples
2995        ///
2996        /// ```
2997        #[doc = concat!("let a: ", stringify!($SelfT), " = 7; // or any other integer type")]
2998        /// let b = 4;
2999        ///
3000        /// assert_eq!(a.rem_euclid(b), 3);
3001        /// assert_eq!((-a).rem_euclid(b), 1);
3002        /// assert_eq!(a.rem_euclid(-b), 3);
3003        /// assert_eq!((-a).rem_euclid(-b), 1);
3004        /// ```
3005        ///
3006        /// This will panic:
3007        /// ```should_panic
3008        #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.rem_euclid(-1);")]
3009        /// ```
3010        #[doc(alias = "modulo", alias = "mod")]
3011        #[stable(feature = "euclidean_division", since = "1.38.0")]
3012        #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")]
3013        #[must_use = "this returns the result of the operation, \
3014                      without modifying the original"]
3015        #[inline]
3016        #[track_caller]
3017        pub const fn rem_euclid(self, rhs: Self) -> Self {
3018            let r = self % rhs;
3019            if r < 0 {
3020                // Semantically equivalent to `if rhs < 0 { r - rhs } else { r + rhs }`.
3021                // If `rhs` is not `Self::MIN`, then `r + abs(rhs)` will not overflow
3022                // and is clearly equivalent, because `r` is negative.
3023                // Otherwise, `rhs` is `Self::MIN`, then we have
3024                // `r.wrapping_add(Self::MIN.wrapping_abs())`, which evaluates
3025                // to `r.wrapping_add(Self::MIN)`, which is equivalent to
3026                // `r - Self::MIN`, which is what we wanted (and will not overflow
3027                // for negative `r`).
3028                r.wrapping_add(rhs.wrapping_abs())
3029            } else {
3030                r
3031            }
3032        }
3033
3034        /// Calculates the quotient of `self` and `rhs`, rounding the result towards negative infinity.
3035        ///
3036        /// # Panics
3037        ///
3038        /// This function will panic if `rhs` is zero or if `self` is `Self::MIN`
3039        /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag.
3040        ///
3041        /// # Examples
3042        ///
3043        /// ```
3044        /// #![feature(int_roundings)]
3045        #[doc = concat!("let a: ", stringify!($SelfT)," = 8;")]
3046        /// let b = 3;
3047        ///
3048        /// assert_eq!(a.div_floor(b), 2);
3049        /// assert_eq!(a.div_floor(-b), -3);
3050        /// assert_eq!((-a).div_floor(b), -3);
3051        /// assert_eq!((-a).div_floor(-b), 2);
3052        /// ```
3053        #[unstable(feature = "int_roundings", issue = "88581")]
3054        #[must_use = "this returns the result of the operation, \
3055                      without modifying the original"]
3056        #[inline]
3057        #[track_caller]
3058        pub const fn div_floor(self, rhs: Self) -> Self {
3059            let d = self / rhs;
3060            let r = self % rhs;
3061
3062            // If the remainder is non-zero, we need to subtract one if the
3063            // signs of self and rhs differ, as this means we rounded upwards
3064            // instead of downwards. We do this branchlessly by creating a mask
3065            // which is all-ones iff the signs differ, and 0 otherwise. Then by
3066            // adding this mask (which corresponds to the signed value -1), we
3067            // get our correction.
3068            let correction = (self ^ rhs) >> (Self::BITS - 1);
3069            if r != 0 {
3070                d + correction
3071            } else {
3072                d
3073            }
3074        }
3075
3076        /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity.
3077        ///
3078        /// # Panics
3079        ///
3080        /// This function will panic if `rhs` is zero or if `self` is `Self::MIN`
3081        /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag.
3082        ///
3083        /// # Examples
3084        ///
3085        /// ```
3086        /// #![feature(int_roundings)]
3087        #[doc = concat!("let a: ", stringify!($SelfT)," = 8;")]
3088        /// let b = 3;
3089        ///
3090        /// assert_eq!(a.div_ceil(b), 3);
3091        /// assert_eq!(a.div_ceil(-b), -2);
3092        /// assert_eq!((-a).div_ceil(b), -2);
3093        /// assert_eq!((-a).div_ceil(-b), 3);
3094        /// ```
3095        #[unstable(feature = "int_roundings", issue = "88581")]
3096        #[must_use = "this returns the result of the operation, \
3097                      without modifying the original"]
3098        #[inline]
3099        #[track_caller]
3100        pub const fn div_ceil(self, rhs: Self) -> Self {
3101            let d = self / rhs;
3102            let r = self % rhs;
3103
3104            // When remainder is non-zero we have a.div_ceil(b) == 1 + a.div_floor(b),
3105            // so we can re-use the algorithm from div_floor, just adding 1.
3106            let correction = 1 + ((self ^ rhs) >> (Self::BITS - 1));
3107            if r != 0 {
3108                d + correction
3109            } else {
3110                d
3111            }
3112        }
3113
3114        /// If `rhs` is positive, calculates the smallest value greater than or
3115        /// equal to `self` that is a multiple of `rhs`. If `rhs` is negative,
3116        /// calculates the largest value less than or equal to `self` that is a
3117        /// multiple of `rhs`.
3118        ///
3119        /// # Panics
3120        ///
3121        /// This function will panic if `rhs` is zero.
3122        ///
3123        /// ## Overflow behavior
3124        ///
3125        /// On overflow, this function will panic if overflow checks are enabled (default in debug
3126        /// mode) and wrap if overflow checks are disabled (default in release mode).
3127        ///
3128        /// # Examples
3129        ///
3130        /// ```
3131        /// #![feature(int_roundings)]
3132        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(8), 16);")]
3133        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(8), 24);")]
3134        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(-8), 16);")]
3135        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(-8), 16);")]
3136        #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").next_multiple_of(8), -16);")]
3137        #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").next_multiple_of(8), -16);")]
3138        #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").next_multiple_of(-8), -16);")]
3139        #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").next_multiple_of(-8), -24);")]
3140        /// ```
3141        #[unstable(feature = "int_roundings", issue = "88581")]
3142        #[must_use = "this returns the result of the operation, \
3143                      without modifying the original"]
3144        #[inline]
3145        #[rustc_inherit_overflow_checks]
3146        pub const fn next_multiple_of(self, rhs: Self) -> Self {
3147            // This would otherwise fail when calculating `r` when self == T::MIN.
3148            if rhs == -1 {
3149                return self;
3150            }
3151
3152            let r = self % rhs;
3153            let m = if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) {
3154                r + rhs
3155            } else {
3156                r
3157            };
3158
3159            if m == 0 {
3160                self
3161            } else {
3162                self + (rhs - m)
3163            }
3164        }
3165
3166        /// If `rhs` is positive, calculates the smallest value greater than or
3167        /// equal to `self` that is a multiple of `rhs`. If `rhs` is negative,
3168        /// calculates the largest value less than or equal to `self` that is a
3169        /// multiple of `rhs`. Returns `None` if `rhs` is zero or the operation
3170        /// would result in overflow.
3171        ///
3172        /// # Examples
3173        ///
3174        /// ```
3175        /// #![feature(int_roundings)]
3176        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(16));")]
3177        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(24));")]
3178        #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(-8), Some(16));")]
3179        #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(-8), Some(16));")]
3180        #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").checked_next_multiple_of(8), Some(-16));")]
3181        #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").checked_next_multiple_of(8), Some(-16));")]
3182        #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").checked_next_multiple_of(-8), Some(-16));")]
3183        #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").checked_next_multiple_of(-8), Some(-24));")]
3184        #[doc = concat!("assert_eq!(1_", stringify!($SelfT), ".checked_next_multiple_of(0), None);")]
3185        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_multiple_of(2), None);")]
3186        /// ```
3187        #[unstable(feature = "int_roundings", issue = "88581")]
3188        #[must_use = "this returns the result of the operation, \
3189                      without modifying the original"]
3190        #[inline]
3191        pub const fn checked_next_multiple_of(self, rhs: Self) -> Option<Self> {
3192            // This would otherwise fail when calculating `r` when self == T::MIN.
3193            if rhs == -1 {
3194                return Some(self);
3195            }
3196
3197            let r = try_opt!(self.checked_rem(rhs));
3198            let m = if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) {
3199                // r + rhs cannot overflow because they have opposite signs
3200                r + rhs
3201            } else {
3202                r
3203            };
3204
3205            if m == 0 {
3206                Some(self)
3207            } else {
3208                // rhs - m cannot overflow because m has the same sign as rhs
3209                self.checked_add(rhs - m)
3210            }
3211        }
3212
3213        /// Returns the logarithm of the number with respect to an arbitrary base,
3214        /// rounded down.
3215        ///
3216        /// This method might not be optimized owing to implementation details;
3217        /// `ilog2` can produce results more efficiently for base 2, and `ilog10`
3218        /// can produce results more efficiently for base 10.
3219        ///
3220        /// # Panics
3221        ///
3222        /// This function will panic if `self` is less than or equal to zero,
3223        /// or if `base` is less than 2.
3224        ///
3225        /// # Examples
3226        ///
3227        /// ```
3228        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")]
3229        /// ```
3230        #[stable(feature = "int_log", since = "1.67.0")]
3231        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
3232        #[must_use = "this returns the result of the operation, \
3233                      without modifying the original"]
3234        #[inline]
3235        #[track_caller]
3236        pub const fn ilog(self, base: Self) -> u32 {
3237            assert!(base >= 2, "base of integer logarithm must be at least 2");
3238            if let Some(log) = self.checked_ilog(base) {
3239                log
3240            } else {
3241                int_log10::panic_for_nonpositive_argument()
3242            }
3243        }
3244
3245        /// Returns the base 2 logarithm of the number, rounded down.
3246        ///
3247        /// # Panics
3248        ///
3249        /// This function will panic if `self` is less than or equal to zero.
3250        ///
3251        /// # Examples
3252        ///
3253        /// ```
3254        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")]
3255        /// ```
3256        #[stable(feature = "int_log", since = "1.67.0")]
3257        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
3258        #[must_use = "this returns the result of the operation, \
3259                      without modifying the original"]
3260        #[inline]
3261        #[track_caller]
3262        pub const fn ilog2(self) -> u32 {
3263            if let Some(log) = self.checked_ilog2() {
3264                log
3265            } else {
3266                int_log10::panic_for_nonpositive_argument()
3267            }
3268        }
3269
3270        /// Returns the base 10 logarithm of the number, rounded down.
3271        ///
3272        /// # Panics
3273        ///
3274        /// This function will panic if `self` is less than or equal to zero.
3275        ///
3276        /// # Example
3277        ///
3278        /// ```
3279        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")]
3280        /// ```
3281        #[stable(feature = "int_log", since = "1.67.0")]
3282        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
3283        #[must_use = "this returns the result of the operation, \
3284                      without modifying the original"]
3285        #[inline]
3286        #[track_caller]
3287        pub const fn ilog10(self) -> u32 {
3288            if let Some(log) = self.checked_ilog10() {
3289                log
3290            } else {
3291                int_log10::panic_for_nonpositive_argument()
3292            }
3293        }
3294
3295        /// Returns the logarithm of the number with respect to an arbitrary base,
3296        /// rounded down.
3297        ///
3298        /// Returns `None` if the number is negative or zero, or if the base is not at least 2.
3299        ///
3300        /// This method might not be optimized owing to implementation details;
3301        /// `checked_ilog2` can produce results more efficiently for base 2, and
3302        /// `checked_ilog10` can produce results more efficiently for base 10.
3303        ///
3304        /// # Examples
3305        ///
3306        /// ```
3307        #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")]
3308        /// ```
3309        #[stable(feature = "int_log", since = "1.67.0")]
3310        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
3311        #[must_use = "this returns the result of the operation, \
3312                      without modifying the original"]
3313        #[inline]
3314        pub const fn checked_ilog(self, base: Self) -> Option<u32> {
3315            if self <= 0 || base <= 1 {
3316                None
3317            } else {
3318                // Delegate to the unsigned implementation.
3319                // The condition makes sure that both casts are exact.
3320                (self as $UnsignedT).checked_ilog(base as $UnsignedT)
3321            }
3322        }
3323
3324        /// Returns the base 2 logarithm of the number, rounded down.
3325        ///
3326        /// Returns `None` if the number is negative or zero.
3327        ///
3328        /// # Examples
3329        ///
3330        /// ```
3331        #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")]
3332        /// ```
3333        #[stable(feature = "int_log", since = "1.67.0")]
3334        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
3335        #[must_use = "this returns the result of the operation, \
3336                      without modifying the original"]
3337        #[inline]
3338        pub const fn checked_ilog2(self) -> Option<u32> {
3339            if self <= 0 {
3340                None
3341            } else {
3342                // SAFETY: We just checked that this number is positive
3343                let log = (Self::BITS - 1) - unsafe { intrinsics::ctlz_nonzero(self) as u32 };
3344                Some(log)
3345            }
3346        }
3347
3348        /// Returns the base 10 logarithm of the number, rounded down.
3349        ///
3350        /// Returns `None` if the number is negative or zero.
3351        ///
3352        /// # Example
3353        ///
3354        /// ```
3355        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")]
3356        /// ```
3357        #[stable(feature = "int_log", since = "1.67.0")]
3358        #[rustc_const_stable(feature = "int_log", since = "1.67.0")]
3359        #[must_use = "this returns the result of the operation, \
3360                      without modifying the original"]
3361        #[inline]
3362        pub const fn checked_ilog10(self) -> Option<u32> {
3363            if self > 0 {
3364                Some(int_log10::$ActualT(self as $ActualT))
3365            } else {
3366                None
3367            }
3368        }
3369
3370        /// Computes the absolute value of `self`.
3371        ///
3372        /// # Overflow behavior
3373        ///
3374        /// The absolute value of
3375        #[doc = concat!("`", stringify!($SelfT), "::MIN`")]
3376        /// cannot be represented as an
3377        #[doc = concat!("`", stringify!($SelfT), "`,")]
3378        /// and attempting to calculate it will cause an overflow. This means
3379        /// that code in debug mode will trigger a panic on this case and
3380        /// optimized code will return
3381        #[doc = concat!("`", stringify!($SelfT), "::MIN`")]
3382        /// without a panic. If you do not want this behavior, consider
3383        /// using [`unsigned_abs`](Self::unsigned_abs) instead.
3384        ///
3385        /// # Examples
3386        ///
3387        /// ```
3388        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".abs(), 10);")]
3389        #[doc = concat!("assert_eq!((-10", stringify!($SelfT), ").abs(), 10);")]
3390        /// ```
3391        #[stable(feature = "rust1", since = "1.0.0")]
3392        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
3393        #[allow(unused_attributes)]
3394        #[must_use = "this returns the result of the operation, \
3395                      without modifying the original"]
3396        #[inline]
3397        #[rustc_inherit_overflow_checks]
3398        pub const fn abs(self) -> Self {
3399            // Note that the #[rustc_inherit_overflow_checks] and #[inline]
3400            // above mean that the overflow semantics of the subtraction
3401            // depend on the crate we're being called from.
3402            if self.is_negative() {
3403                -self
3404            } else {
3405                self
3406            }
3407        }
3408
3409        /// Computes the absolute difference between `self` and `other`.
3410        ///
3411        /// This function always returns the correct answer without overflow or
3412        /// panics by returning an unsigned integer.
3413        ///
3414        /// # Examples
3415        ///
3416        /// ```
3417        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(80), 20", stringify!($UnsignedT), ");")]
3418        #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(110), 10", stringify!($UnsignedT), ");")]
3419        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").abs_diff(80), 180", stringify!($UnsignedT), ");")]
3420        #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").abs_diff(-120), 20", stringify!($UnsignedT), ");")]
3421        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.abs_diff(", stringify!($SelfT), "::MAX), ", stringify!($UnsignedT), "::MAX);")]
3422        /// ```
3423        #[stable(feature = "int_abs_diff", since = "1.60.0")]
3424        #[rustc_const_stable(feature = "int_abs_diff", since = "1.60.0")]
3425        #[must_use = "this returns the result of the operation, \
3426                      without modifying the original"]
3427        #[inline]
3428        pub const fn abs_diff(self, other: Self) -> $UnsignedT {
3429            if self < other {
3430                // Converting a non-negative x from signed to unsigned by using
3431                // `x as U` is left unchanged, but a negative x is converted
3432                // to value x + 2^N. Thus if `s` and `o` are binary variables
3433                // respectively indicating whether `self` and `other` are
3434                // negative, we are computing the mathematical value:
3435                //
3436                //    (other + o*2^N) - (self + s*2^N)    mod  2^N
3437                //    other - self + (o-s)*2^N            mod  2^N
3438                //    other - self                        mod  2^N
3439                //
3440                // Finally, taking the mod 2^N of the mathematical value of
3441                // `other - self` does not change it as it already is
3442                // in the range [0, 2^N).
3443                (other as $UnsignedT).wrapping_sub(self as $UnsignedT)
3444            } else {
3445                (self as $UnsignedT).wrapping_sub(other as $UnsignedT)
3446            }
3447        }
3448
3449        /// Returns a number representing sign of `self`.
3450        ///
3451        ///  - `0` if the number is zero
3452        ///  - `1` if the number is positive
3453        ///  - `-1` if the number is negative
3454        ///
3455        /// # Examples
3456        ///
3457        /// ```
3458        #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".signum(), 1);")]
3459        #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".signum(), 0);")]
3460        #[doc = concat!("assert_eq!((-10", stringify!($SelfT), ").signum(), -1);")]
3461        /// ```
3462        #[stable(feature = "rust1", since = "1.0.0")]
3463        #[rustc_const_stable(feature = "const_int_sign", since = "1.47.0")]
3464        #[must_use = "this returns the result of the operation, \
3465                      without modifying the original"]
3466        #[inline(always)]
3467        pub const fn signum(self) -> Self {
3468            // Picking the right way to phrase this is complicated
3469            // (<https://graphics.stanford.edu/~seander/bithacks.html#CopyIntegerSign>)
3470            // so delegate it to `Ord` which is already producing -1/0/+1
3471            // exactly like we need and can be the place to deal with the complexity.
3472
3473            crate::intrinsics::three_way_compare(self, 0) as Self
3474        }
3475
3476        /// Returns `true` if `self` is positive and `false` if the number is zero or
3477        /// negative.
3478        ///
3479        /// # Examples
3480        ///
3481        /// ```
3482        #[doc = concat!("assert!(10", stringify!($SelfT), ".is_positive());")]
3483        #[doc = concat!("assert!(!(-10", stringify!($SelfT), ").is_positive());")]
3484        /// ```
3485        #[must_use]
3486        #[stable(feature = "rust1", since = "1.0.0")]
3487        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
3488        #[inline(always)]
3489        pub const fn is_positive(self) -> bool { self > 0 }
3490
3491        /// Returns `true` if `self` is negative and `false` if the number is zero or
3492        /// positive.
3493        ///
3494        /// # Examples
3495        ///
3496        /// ```
3497        #[doc = concat!("assert!((-10", stringify!($SelfT), ").is_negative());")]
3498        #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_negative());")]
3499        /// ```
3500        #[must_use]
3501        #[stable(feature = "rust1", since = "1.0.0")]
3502        #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
3503        #[inline(always)]
3504        pub const fn is_negative(self) -> bool { self < 0 }
3505
3506        /// Returns the memory representation of this integer as a byte array in
3507        /// big-endian (network) byte order.
3508        ///
3509        #[doc = $to_xe_bytes_doc]
3510        ///
3511        /// # Examples
3512        ///
3513        /// ```
3514        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_be_bytes();")]
3515        #[doc = concat!("assert_eq!(bytes, ", $be_bytes, ");")]
3516        /// ```
3517        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3518        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3519        #[must_use = "this returns the result of the operation, \
3520                      without modifying the original"]
3521        #[inline]
3522        pub const fn to_be_bytes(self) -> [u8; size_of::<Self>()] {
3523            self.to_be().to_ne_bytes()
3524        }
3525
3526        /// Returns the memory representation of this integer as a byte array in
3527        /// little-endian byte order.
3528        ///
3529        #[doc = $to_xe_bytes_doc]
3530        ///
3531        /// # Examples
3532        ///
3533        /// ```
3534        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_le_bytes();")]
3535        #[doc = concat!("assert_eq!(bytes, ", $le_bytes, ");")]
3536        /// ```
3537        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3538        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3539        #[must_use = "this returns the result of the operation, \
3540                      without modifying the original"]
3541        #[inline]
3542        pub const fn to_le_bytes(self) -> [u8; size_of::<Self>()] {
3543            self.to_le().to_ne_bytes()
3544        }
3545
3546        /// Returns the memory representation of this integer as a byte array in
3547        /// native byte order.
3548        ///
3549        /// As the target platform's native endianness is used, portable code
3550        /// should use [`to_be_bytes`] or [`to_le_bytes`], as appropriate,
3551        /// instead.
3552        ///
3553        #[doc = $to_xe_bytes_doc]
3554        ///
3555        /// [`to_be_bytes`]: Self::to_be_bytes
3556        /// [`to_le_bytes`]: Self::to_le_bytes
3557        ///
3558        /// # Examples
3559        ///
3560        /// ```
3561        #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_ne_bytes();")]
3562        /// assert_eq!(
3563        ///     bytes,
3564        ///     if cfg!(target_endian = "big") {
3565        #[doc = concat!("        ", $be_bytes)]
3566        ///     } else {
3567        #[doc = concat!("        ", $le_bytes)]
3568        ///     }
3569        /// );
3570        /// ```
3571        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3572        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3573        #[allow(unnecessary_transmutes)]
3574        // SAFETY: const sound because integers are plain old datatypes so we can always
3575        // transmute them to arrays of bytes
3576        #[must_use = "this returns the result of the operation, \
3577                      without modifying the original"]
3578        #[inline]
3579        pub const fn to_ne_bytes(self) -> [u8; size_of::<Self>()] {
3580            // SAFETY: integers are plain old datatypes so we can always transmute them to
3581            // arrays of bytes
3582            unsafe { mem::transmute(self) }
3583        }
3584
3585        /// Creates an integer value from its representation as a byte array in
3586        /// big endian.
3587        ///
3588        #[doc = $from_xe_bytes_doc]
3589        ///
3590        /// # Examples
3591        ///
3592        /// ```
3593        #[doc = concat!("let value = ", stringify!($SelfT), "::from_be_bytes(", $be_bytes, ");")]
3594        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3595        /// ```
3596        ///
3597        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3598        ///
3599        /// ```
3600        #[doc = concat!("fn read_be_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3601        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3602        ///     *input = rest;
3603        #[doc = concat!("    ", stringify!($SelfT), "::from_be_bytes(int_bytes.try_into().unwrap())")]
3604        /// }
3605        /// ```
3606        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3607        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3608        #[must_use]
3609        #[inline]
3610        pub const fn from_be_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3611            Self::from_be(Self::from_ne_bytes(bytes))
3612        }
3613
3614        /// Creates an integer value from its representation as a byte array in
3615        /// little endian.
3616        ///
3617        #[doc = $from_xe_bytes_doc]
3618        ///
3619        /// # Examples
3620        ///
3621        /// ```
3622        #[doc = concat!("let value = ", stringify!($SelfT), "::from_le_bytes(", $le_bytes, ");")]
3623        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3624        /// ```
3625        ///
3626        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3627        ///
3628        /// ```
3629        #[doc = concat!("fn read_le_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3630        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3631        ///     *input = rest;
3632        #[doc = concat!("    ", stringify!($SelfT), "::from_le_bytes(int_bytes.try_into().unwrap())")]
3633        /// }
3634        /// ```
3635        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3636        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3637        #[must_use]
3638        #[inline]
3639        pub const fn from_le_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3640            Self::from_le(Self::from_ne_bytes(bytes))
3641        }
3642
3643        /// Creates an integer value from its memory representation as a byte
3644        /// array in native endianness.
3645        ///
3646        /// As the target platform's native endianness is used, portable code
3647        /// likely wants to use [`from_be_bytes`] or [`from_le_bytes`], as
3648        /// appropriate instead.
3649        ///
3650        /// [`from_be_bytes`]: Self::from_be_bytes
3651        /// [`from_le_bytes`]: Self::from_le_bytes
3652        ///
3653        #[doc = $from_xe_bytes_doc]
3654        ///
3655        /// # Examples
3656        ///
3657        /// ```
3658        #[doc = concat!("let value = ", stringify!($SelfT), "::from_ne_bytes(if cfg!(target_endian = \"big\") {")]
3659        #[doc = concat!("    ", $be_bytes)]
3660        /// } else {
3661        #[doc = concat!("    ", $le_bytes)]
3662        /// });
3663        #[doc = concat!("assert_eq!(value, ", $swap_op, ");")]
3664        /// ```
3665        ///
3666        /// When starting from a slice rather than an array, fallible conversion APIs can be used:
3667        ///
3668        /// ```
3669        #[doc = concat!("fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")]
3670        #[doc = concat!("    let (int_bytes, rest) = input.split_at(size_of::<", stringify!($SelfT), ">());")]
3671        ///     *input = rest;
3672        #[doc = concat!("    ", stringify!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())")]
3673        /// }
3674        /// ```
3675        #[stable(feature = "int_to_from_bytes", since = "1.32.0")]
3676        #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
3677        #[allow(unnecessary_transmutes)]
3678        #[must_use]
3679        // SAFETY: const sound because integers are plain old datatypes so we can always
3680        // transmute to them
3681        #[inline]
3682        pub const fn from_ne_bytes(bytes: [u8; size_of::<Self>()]) -> Self {
3683            // SAFETY: integers are plain old datatypes so we can always transmute to them
3684            unsafe { mem::transmute(bytes) }
3685        }
3686
3687        /// New code should prefer to use
3688        #[doc = concat!("[`", stringify!($SelfT), "::MIN", "`] instead.")]
3689        ///
3690        /// Returns the smallest value that can be represented by this integer type.
3691        #[stable(feature = "rust1", since = "1.0.0")]
3692        #[inline(always)]
3693        #[rustc_promotable]
3694        #[rustc_const_stable(feature = "const_min_value", since = "1.32.0")]
3695        #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")]
3696        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value")]
3697        pub const fn min_value() -> Self {
3698            Self::MIN
3699        }
3700
3701        /// New code should prefer to use
3702        #[doc = concat!("[`", stringify!($SelfT), "::MAX", "`] instead.")]
3703        ///
3704        /// Returns the largest value that can be represented by this integer type.
3705        #[stable(feature = "rust1", since = "1.0.0")]
3706        #[inline(always)]
3707        #[rustc_promotable]
3708        #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
3709        #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")]
3710        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value")]
3711        pub const fn max_value() -> Self {
3712            Self::MAX
3713        }
3714    }
3715}