1 //===-- llvm/ADT/APInt.h - For Arbitrary Precision Integer -----*- C++ -*--===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// This file implements a class to represent arbitrary precision
11 /// integral constant values and operations on them.
12 ///
13 //===----------------------------------------------------------------------===//
14
15 #ifndef LLVM_ADT_APINT_H
16 #define LLVM_ADT_APINT_H
17
18 #include "llvm/Support/Compiler.h"
19 #include "llvm/Support/MathExtras.h"
20 #include <cassert>
21 #include <climits>
22 #include <cstring>
23 #include <string>
24
25 namespace llvm {
26 class FoldingSetNodeID;
27 class StringRef;
28 class hash_code;
29 class raw_ostream;
30
31 template <typename T> class SmallVectorImpl;
32 template <typename T> class ArrayRef;
33 template <typename T> class Optional;
34
35 class APInt;
36
37 inline APInt operator-(APInt);
38
39 //===----------------------------------------------------------------------===//
40 // APInt Class
41 //===----------------------------------------------------------------------===//
42
43 /// Class for arbitrary precision integers.
44 ///
45 /// APInt is a functional replacement for common case unsigned integer type like
46 /// "unsigned", "unsigned long" or "uint64_t", but also allows non-byte-width
47 /// integer sizes and large integer value types such as 3-bits, 15-bits, or more
48 /// than 64-bits of precision. APInt provides a variety of arithmetic operators
49 /// and methods to manipulate integer values of any bit-width. It supports both
50 /// the typical integer arithmetic and comparison operations as well as bitwise
51 /// manipulation.
52 ///
53 /// The class has several invariants worth noting:
54 /// * All bit, byte, and word positions are zero-based.
55 /// * Once the bit width is set, it doesn't change except by the Truncate,
56 /// SignExtend, or ZeroExtend operations.
57 /// * All binary operators must be on APInt instances of the same bit width.
58 /// Attempting to use these operators on instances with different bit
59 /// widths will yield an assertion.
60 /// * The value is stored canonically as an unsigned value. For operations
61 /// where it makes a difference, there are both signed and unsigned variants
62 /// of the operation. For example, sdiv and udiv. However, because the bit
63 /// widths must be the same, operations such as Mul and Add produce the same
64 /// results regardless of whether the values are interpreted as signed or
65 /// not.
66 /// * In general, the class tries to follow the style of computation that LLVM
67 /// uses in its IR. This simplifies its use for LLVM.
68 ///
69 class LLVM_NODISCARD APInt {
70 public:
71 typedef uint64_t WordType;
72
73 /// This enum is used to hold the constants we needed for APInt.
74 enum : unsigned {
75 /// Byte size of a word.
76 APINT_WORD_SIZE = sizeof(WordType),
77 /// Bits in a word.
78 APINT_BITS_PER_WORD = APINT_WORD_SIZE * CHAR_BIT
79 };
80
81 enum class Rounding {
82 DOWN,
83 TOWARD_ZERO,
84 UP,
85 };
86
87 static const WordType WORDTYPE_MAX = ~WordType(0);
88
89 private:
90 /// This union is used to store the integer value. When the
91 /// integer bit-width <= 64, it uses VAL, otherwise it uses pVal.
92 union {
93 uint64_t VAL; ///< Used to store the <= 64 bits integer value.
94 uint64_t *pVal; ///< Used to store the >64 bits integer value.
95 } U;
96
97 unsigned BitWidth; ///< The number of bits in this APInt.
98
99 friend struct DenseMapAPIntKeyInfo;
100
101 friend class APSInt;
102
103 /// Fast internal constructor
104 ///
105 /// This constructor is used only internally for speed of construction of
106 /// temporaries. It is unsafe for general use so it is not public.
APInt(uint64_t * val,unsigned bits)107 APInt(uint64_t *val, unsigned bits) : BitWidth(bits) {
108 U.pVal = val;
109 }
110
111 /// Determine if this APInt just has one word to store value.
112 ///
113 /// \returns true if the number of bits <= 64, false otherwise.
isSingleWord()114 bool isSingleWord() const { return BitWidth <= APINT_BITS_PER_WORD; }
115
116 /// Determine which word a bit is in.
117 ///
118 /// \returns the word position for the specified bit position.
whichWord(unsigned bitPosition)119 static unsigned whichWord(unsigned bitPosition) {
120 return bitPosition / APINT_BITS_PER_WORD;
121 }
122
123 /// Determine which bit in a word a bit is in.
124 ///
125 /// \returns the bit position in a word for the specified bit position
126 /// in the APInt.
whichBit(unsigned bitPosition)127 static unsigned whichBit(unsigned bitPosition) {
128 return bitPosition % APINT_BITS_PER_WORD;
129 }
130
131 /// Get a single bit mask.
132 ///
133 /// \returns a uint64_t with only bit at "whichBit(bitPosition)" set
134 /// This method generates and returns a uint64_t (word) mask for a single
135 /// bit at a specific bit position. This is used to mask the bit in the
136 /// corresponding word.
maskBit(unsigned bitPosition)137 static uint64_t maskBit(unsigned bitPosition) {
138 return 1ULL << whichBit(bitPosition);
139 }
140
141 /// Clear unused high order bits
142 ///
143 /// This method is used internally to clear the top "N" bits in the high order
144 /// word that are not used by the APInt. This is needed after the most
145 /// significant word is assigned a value to ensure that those bits are
146 /// zero'd out.
clearUnusedBits()147 APInt &clearUnusedBits() {
148 // Compute how many bits are used in the final word
149 unsigned WordBits = ((BitWidth-1) % APINT_BITS_PER_WORD) + 1;
150
151 // Mask out the high bits.
152 uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - WordBits);
153 if (isSingleWord())
154 U.VAL &= mask;
155 else
156 U.pVal[getNumWords() - 1] &= mask;
157 return *this;
158 }
159
160 /// Get the word corresponding to a bit position
161 /// \returns the corresponding word for the specified bit position.
getWord(unsigned bitPosition)162 uint64_t getWord(unsigned bitPosition) const {
163 return isSingleWord() ? U.VAL : U.pVal[whichWord(bitPosition)];
164 }
165
166 /// Utility method to change the bit width of this APInt to new bit width,
167 /// allocating and/or deallocating as necessary. There is no guarantee on the
168 /// value of any bits upon return. Caller should populate the bits after.
169 void reallocate(unsigned NewBitWidth);
170
171 /// Convert a char array into an APInt
172 ///
173 /// \param radix 2, 8, 10, 16, or 36
174 /// Converts a string into a number. The string must be non-empty
175 /// and well-formed as a number of the given base. The bit-width
176 /// must be sufficient to hold the result.
177 ///
178 /// This is used by the constructors that take string arguments.
179 ///
180 /// StringRef::getAsInteger is superficially similar but (1) does
181 /// not assume that the string is well-formed and (2) grows the
182 /// result to hold the input.
183 void fromString(unsigned numBits, StringRef str, uint8_t radix);
184
185 /// An internal division function for dividing APInts.
186 ///
187 /// This is used by the toString method to divide by the radix. It simply
188 /// provides a more convenient form of divide for internal use since KnuthDiv
189 /// has specific constraints on its inputs. If those constraints are not met
190 /// then it provides a simpler form of divide.
191 static void divide(const WordType *LHS, unsigned lhsWords,
192 const WordType *RHS, unsigned rhsWords, WordType *Quotient,
193 WordType *Remainder);
194
195 /// out-of-line slow case for inline constructor
196 void initSlowCase(uint64_t val, bool isSigned);
197
198 /// shared code between two array constructors
199 void initFromArray(ArrayRef<uint64_t> array);
200
201 /// out-of-line slow case for inline copy constructor
202 void initSlowCase(const APInt &that);
203
204 /// out-of-line slow case for shl
205 void shlSlowCase(unsigned ShiftAmt);
206
207 /// out-of-line slow case for lshr.
208 void lshrSlowCase(unsigned ShiftAmt);
209
210 /// out-of-line slow case for ashr.
211 void ashrSlowCase(unsigned ShiftAmt);
212
213 /// out-of-line slow case for operator=
214 void AssignSlowCase(const APInt &RHS);
215
216 /// out-of-line slow case for operator==
217 bool EqualSlowCase(const APInt &RHS) const LLVM_READONLY;
218
219 /// out-of-line slow case for countLeadingZeros
220 unsigned countLeadingZerosSlowCase() const LLVM_READONLY;
221
222 /// out-of-line slow case for countLeadingOnes.
223 unsigned countLeadingOnesSlowCase() const LLVM_READONLY;
224
225 /// out-of-line slow case for countTrailingZeros.
226 unsigned countTrailingZerosSlowCase() const LLVM_READONLY;
227
228 /// out-of-line slow case for countTrailingOnes
229 unsigned countTrailingOnesSlowCase() const LLVM_READONLY;
230
231 /// out-of-line slow case for countPopulation
232 unsigned countPopulationSlowCase() const LLVM_READONLY;
233
234 /// out-of-line slow case for intersects.
235 bool intersectsSlowCase(const APInt &RHS) const LLVM_READONLY;
236
237 /// out-of-line slow case for isSubsetOf.
238 bool isSubsetOfSlowCase(const APInt &RHS) const LLVM_READONLY;
239
240 /// out-of-line slow case for setBits.
241 void setBitsSlowCase(unsigned loBit, unsigned hiBit);
242
243 /// out-of-line slow case for flipAllBits.
244 void flipAllBitsSlowCase();
245
246 /// out-of-line slow case for operator&=.
247 void AndAssignSlowCase(const APInt& RHS);
248
249 /// out-of-line slow case for operator|=.
250 void OrAssignSlowCase(const APInt& RHS);
251
252 /// out-of-line slow case for operator^=.
253 void XorAssignSlowCase(const APInt& RHS);
254
255 /// Unsigned comparison. Returns -1, 0, or 1 if this APInt is less than, equal
256 /// to, or greater than RHS.
257 int compare(const APInt &RHS) const LLVM_READONLY;
258
259 /// Signed comparison. Returns -1, 0, or 1 if this APInt is less than, equal
260 /// to, or greater than RHS.
261 int compareSigned(const APInt &RHS) const LLVM_READONLY;
262
263 public:
264 /// \name Constructors
265 /// @{
266
267 /// Create a new APInt of numBits width, initialized as val.
268 ///
269 /// If isSigned is true then val is treated as if it were a signed value
270 /// (i.e. as an int64_t) and the appropriate sign extension to the bit width
271 /// will be done. Otherwise, no sign extension occurs (high order bits beyond
272 /// the range of val are zero filled).
273 ///
274 /// \param numBits the bit width of the constructed APInt
275 /// \param val the initial value of the APInt
276 /// \param isSigned how to treat signedness of val
277 APInt(unsigned numBits, uint64_t val, bool isSigned = false)
BitWidth(numBits)278 : BitWidth(numBits) {
279 assert(BitWidth && "bitwidth too small");
280 if (isSingleWord()) {
281 U.VAL = val;
282 clearUnusedBits();
283 } else {
284 initSlowCase(val, isSigned);
285 }
286 }
287
288 /// Construct an APInt of numBits width, initialized as bigVal[].
289 ///
290 /// Note that bigVal.size() can be smaller or larger than the corresponding
291 /// bit width but any extraneous bits will be dropped.
292 ///
293 /// \param numBits the bit width of the constructed APInt
294 /// \param bigVal a sequence of words to form the initial value of the APInt
295 APInt(unsigned numBits, ArrayRef<uint64_t> bigVal);
296
297 /// Equivalent to APInt(numBits, ArrayRef<uint64_t>(bigVal, numWords)), but
298 /// deprecated because this constructor is prone to ambiguity with the
299 /// APInt(unsigned, uint64_t, bool) constructor.
300 ///
301 /// If this overload is ever deleted, care should be taken to prevent calls
302 /// from being incorrectly captured by the APInt(unsigned, uint64_t, bool)
303 /// constructor.
304 APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[]);
305
306 /// Construct an APInt from a string representation.
307 ///
308 /// This constructor interprets the string \p str in the given radix. The
309 /// interpretation stops when the first character that is not suitable for the
310 /// radix is encountered, or the end of the string. Acceptable radix values
311 /// are 2, 8, 10, 16, and 36. It is an error for the value implied by the
312 /// string to require more bits than numBits.
313 ///
314 /// \param numBits the bit width of the constructed APInt
315 /// \param str the string to be interpreted
316 /// \param radix the radix to use for the conversion
317 APInt(unsigned numBits, StringRef str, uint8_t radix);
318
319 /// Simply makes *this a copy of that.
320 /// Copy Constructor.
APInt(const APInt & that)321 APInt(const APInt &that) : BitWidth(that.BitWidth) {
322 if (isSingleWord())
323 U.VAL = that.U.VAL;
324 else
325 initSlowCase(that);
326 }
327
328 /// Move Constructor.
APInt(APInt && that)329 APInt(APInt &&that) : BitWidth(that.BitWidth) {
330 memcpy(&U, &that.U, sizeof(U));
331 that.BitWidth = 0;
332 }
333
334 /// Destructor.
~APInt()335 ~APInt() {
336 if (needsCleanup())
337 delete[] U.pVal;
338 }
339
340 /// Default constructor that creates an uninteresting APInt
341 /// representing a 1-bit zero value.
342 ///
343 /// This is useful for object deserialization (pair this with the static
344 /// method Read).
APInt()345 explicit APInt() : BitWidth(1) { U.VAL = 0; }
346
347 /// Returns whether this instance allocated memory.
needsCleanup()348 bool needsCleanup() const { return !isSingleWord(); }
349
350 /// Used to insert APInt objects, or objects that contain APInt objects, into
351 /// FoldingSets.
352 void Profile(FoldingSetNodeID &id) const;
353
354 /// @}
355 /// \name Value Tests
356 /// @{
357
358 /// Determine sign of this APInt.
359 ///
360 /// This tests the high bit of this APInt to determine if it is set.
361 ///
362 /// \returns true if this APInt is negative, false otherwise
isNegative()363 bool isNegative() const { return (*this)[BitWidth - 1]; }
364
365 /// Determine if this APInt Value is non-negative (>= 0)
366 ///
367 /// This tests the high bit of the APInt to determine if it is unset.
isNonNegative()368 bool isNonNegative() const { return !isNegative(); }
369
370 /// Determine if sign bit of this APInt is set.
371 ///
372 /// This tests the high bit of this APInt to determine if it is set.
373 ///
374 /// \returns true if this APInt has its sign bit set, false otherwise.
isSignBitSet()375 bool isSignBitSet() const { return (*this)[BitWidth-1]; }
376
377 /// Determine if sign bit of this APInt is clear.
378 ///
379 /// This tests the high bit of this APInt to determine if it is clear.
380 ///
381 /// \returns true if this APInt has its sign bit clear, false otherwise.
isSignBitClear()382 bool isSignBitClear() const { return !isSignBitSet(); }
383
384 /// Determine if this APInt Value is positive.
385 ///
386 /// This tests if the value of this APInt is positive (> 0). Note
387 /// that 0 is not a positive value.
388 ///
389 /// \returns true if this APInt is positive.
isStrictlyPositive()390 bool isStrictlyPositive() const { return isNonNegative() && !isNullValue(); }
391
392 /// Determine if this APInt Value is non-positive (<= 0).
393 ///
394 /// \returns true if this APInt is non-positive.
isNonPositive()395 bool isNonPositive() const { return !isStrictlyPositive(); }
396
397 /// Determine if all bits are set
398 ///
399 /// This checks to see if the value has all bits of the APInt are set or not.
isAllOnesValue()400 bool isAllOnesValue() const {
401 if (isSingleWord())
402 return U.VAL == WORDTYPE_MAX >> (APINT_BITS_PER_WORD - BitWidth);
403 return countTrailingOnesSlowCase() == BitWidth;
404 }
405
406 /// Determine if all bits are clear
407 ///
408 /// This checks to see if the value has all bits of the APInt are clear or
409 /// not.
isNullValue()410 bool isNullValue() const { return !*this; }
411
412 /// Determine if this is a value of 1.
413 ///
414 /// This checks to see if the value of this APInt is one.
isOneValue()415 bool isOneValue() const {
416 if (isSingleWord())
417 return U.VAL == 1;
418 return countLeadingZerosSlowCase() == BitWidth - 1;
419 }
420
421 /// Determine if this is the largest unsigned value.
422 ///
423 /// This checks to see if the value of this APInt is the maximum unsigned
424 /// value for the APInt's bit width.
isMaxValue()425 bool isMaxValue() const { return isAllOnesValue(); }
426
427 /// Determine if this is the largest signed value.
428 ///
429 /// This checks to see if the value of this APInt is the maximum signed
430 /// value for the APInt's bit width.
isMaxSignedValue()431 bool isMaxSignedValue() const {
432 if (isSingleWord())
433 return U.VAL == ((WordType(1) << (BitWidth - 1)) - 1);
434 return !isNegative() && countTrailingOnesSlowCase() == BitWidth - 1;
435 }
436
437 /// Determine if this is the smallest unsigned value.
438 ///
439 /// This checks to see if the value of this APInt is the minimum unsigned
440 /// value for the APInt's bit width.
isMinValue()441 bool isMinValue() const { return isNullValue(); }
442
443 /// Determine if this is the smallest signed value.
444 ///
445 /// This checks to see if the value of this APInt is the minimum signed
446 /// value for the APInt's bit width.
isMinSignedValue()447 bool isMinSignedValue() const {
448 if (isSingleWord())
449 return U.VAL == (WordType(1) << (BitWidth - 1));
450 return isNegative() && countTrailingZerosSlowCase() == BitWidth - 1;
451 }
452
453 /// Check if this APInt has an N-bits unsigned integer value.
isIntN(unsigned N)454 bool isIntN(unsigned N) const {
455 assert(N && "N == 0 ???");
456 return getActiveBits() <= N;
457 }
458
459 /// Check if this APInt has an N-bits signed integer value.
isSignedIntN(unsigned N)460 bool isSignedIntN(unsigned N) const {
461 assert(N && "N == 0 ???");
462 return getMinSignedBits() <= N;
463 }
464
465 /// Check if this APInt's value is a power of two greater than zero.
466 ///
467 /// \returns true if the argument APInt value is a power of two > 0.
isPowerOf2()468 bool isPowerOf2() const {
469 if (isSingleWord())
470 return isPowerOf2_64(U.VAL);
471 return countPopulationSlowCase() == 1;
472 }
473
474 /// Check if the APInt's value is returned by getSignMask.
475 ///
476 /// \returns true if this is the value returned by getSignMask.
isSignMask()477 bool isSignMask() const { return isMinSignedValue(); }
478
479 /// Convert APInt to a boolean value.
480 ///
481 /// This converts the APInt to a boolean value as a test against zero.
getBoolValue()482 bool getBoolValue() const { return !!*this; }
483
484 /// If this value is smaller than the specified limit, return it, otherwise
485 /// return the limit value. This causes the value to saturate to the limit.
486 uint64_t getLimitedValue(uint64_t Limit = UINT64_MAX) const {
487 return ugt(Limit) ? Limit : getZExtValue();
488 }
489
490 /// Check if the APInt consists of a repeated bit pattern.
491 ///
492 /// e.g. 0x01010101 satisfies isSplat(8).
493 /// \param SplatSizeInBits The size of the pattern in bits. Must divide bit
494 /// width without remainder.
495 bool isSplat(unsigned SplatSizeInBits) const;
496
497 /// \returns true if this APInt value is a sequence of \param numBits ones
498 /// starting at the least significant bit with the remainder zero.
isMask(unsigned numBits)499 bool isMask(unsigned numBits) const {
500 assert(numBits != 0 && "numBits must be non-zero");
501 assert(numBits <= BitWidth && "numBits out of range");
502 if (isSingleWord())
503 return U.VAL == (WORDTYPE_MAX >> (APINT_BITS_PER_WORD - numBits));
504 unsigned Ones = countTrailingOnesSlowCase();
505 return (numBits == Ones) &&
506 ((Ones + countLeadingZerosSlowCase()) == BitWidth);
507 }
508
509 /// \returns true if this APInt is a non-empty sequence of ones starting at
510 /// the least significant bit with the remainder zero.
511 /// Ex. isMask(0x0000FFFFU) == true.
isMask()512 bool isMask() const {
513 if (isSingleWord())
514 return isMask_64(U.VAL);
515 unsigned Ones = countTrailingOnesSlowCase();
516 return (Ones > 0) && ((Ones + countLeadingZerosSlowCase()) == BitWidth);
517 }
518
519 /// Return true if this APInt value contains a sequence of ones with
520 /// the remainder zero.
isShiftedMask()521 bool isShiftedMask() const {
522 if (isSingleWord())
523 return isShiftedMask_64(U.VAL);
524 unsigned Ones = countPopulationSlowCase();
525 unsigned LeadZ = countLeadingZerosSlowCase();
526 return (Ones + LeadZ + countTrailingZeros()) == BitWidth;
527 }
528
529 /// @}
530 /// \name Value Generators
531 /// @{
532
533 /// Gets maximum unsigned value of APInt for specific bit width.
getMaxValue(unsigned numBits)534 static APInt getMaxValue(unsigned numBits) {
535 return getAllOnesValue(numBits);
536 }
537
538 /// Gets maximum signed value of APInt for a specific bit width.
getSignedMaxValue(unsigned numBits)539 static APInt getSignedMaxValue(unsigned numBits) {
540 APInt API = getAllOnesValue(numBits);
541 API.clearBit(numBits - 1);
542 return API;
543 }
544
545 /// Gets minimum unsigned value of APInt for a specific bit width.
getMinValue(unsigned numBits)546 static APInt getMinValue(unsigned numBits) { return APInt(numBits, 0); }
547
548 /// Gets minimum signed value of APInt for a specific bit width.
getSignedMinValue(unsigned numBits)549 static APInt getSignedMinValue(unsigned numBits) {
550 APInt API(numBits, 0);
551 API.setBit(numBits - 1);
552 return API;
553 }
554
555 /// Get the SignMask for a specific bit width.
556 ///
557 /// This is just a wrapper function of getSignedMinValue(), and it helps code
558 /// readability when we want to get a SignMask.
getSignMask(unsigned BitWidth)559 static APInt getSignMask(unsigned BitWidth) {
560 return getSignedMinValue(BitWidth);
561 }
562
563 /// Get the all-ones value.
564 ///
565 /// \returns the all-ones value for an APInt of the specified bit-width.
getAllOnesValue(unsigned numBits)566 static APInt getAllOnesValue(unsigned numBits) {
567 return APInt(numBits, WORDTYPE_MAX, true);
568 }
569
570 /// Get the '0' value.
571 ///
572 /// \returns the '0' value for an APInt of the specified bit-width.
getNullValue(unsigned numBits)573 static APInt getNullValue(unsigned numBits) { return APInt(numBits, 0); }
574
575 /// Compute an APInt containing numBits highbits from this APInt.
576 ///
577 /// Get an APInt with the same BitWidth as this APInt, just zero mask
578 /// the low bits and right shift to the least significant bit.
579 ///
580 /// \returns the high "numBits" bits of this APInt.
581 APInt getHiBits(unsigned numBits) const;
582
583 /// Compute an APInt containing numBits lowbits from this APInt.
584 ///
585 /// Get an APInt with the same BitWidth as this APInt, just zero mask
586 /// the high bits.
587 ///
588 /// \returns the low "numBits" bits of this APInt.
589 APInt getLoBits(unsigned numBits) const;
590
591 /// Return an APInt with exactly one bit set in the result.
getOneBitSet(unsigned numBits,unsigned BitNo)592 static APInt getOneBitSet(unsigned numBits, unsigned BitNo) {
593 APInt Res(numBits, 0);
594 Res.setBit(BitNo);
595 return Res;
596 }
597
598 /// Get a value with a block of bits set.
599 ///
600 /// Constructs an APInt value that has a contiguous range of bits set. The
601 /// bits from loBit (inclusive) to hiBit (exclusive) will be set. All other
602 /// bits will be zero. For example, with parameters(32, 0, 16) you would get
603 /// 0x0000FFFF. Please call getBitsSetWithWrap if \p loBit may be greater than
604 /// \p hiBit.
605 ///
606 /// \param numBits the intended bit width of the result
607 /// \param loBit the index of the lowest bit set.
608 /// \param hiBit the index of the highest bit set.
609 ///
610 /// \returns An APInt value with the requested bits set.
getBitsSet(unsigned numBits,unsigned loBit,unsigned hiBit)611 static APInt getBitsSet(unsigned numBits, unsigned loBit, unsigned hiBit) {
612 assert(loBit <= hiBit && "loBit greater than hiBit");
613 APInt Res(numBits, 0);
614 Res.setBits(loBit, hiBit);
615 return Res;
616 }
617
618 /// Wrap version of getBitsSet.
619 /// If \p hiBit is no less than \p loBit, this is same with getBitsSet.
620 /// If \p hiBit is less than \p loBit, the set bits "wrap". For example, with
621 /// parameters (32, 28, 4), you would get 0xF000000F.
getBitsSetWithWrap(unsigned numBits,unsigned loBit,unsigned hiBit)622 static APInt getBitsSetWithWrap(unsigned numBits, unsigned loBit,
623 unsigned hiBit) {
624 APInt Res(numBits, 0);
625 Res.setBitsWithWrap(loBit, hiBit);
626 return Res;
627 }
628
629 /// Get a value with upper bits starting at loBit set.
630 ///
631 /// Constructs an APInt value that has a contiguous range of bits set. The
632 /// bits from loBit (inclusive) to numBits (exclusive) will be set. All other
633 /// bits will be zero. For example, with parameters(32, 12) you would get
634 /// 0xFFFFF000.
635 ///
636 /// \param numBits the intended bit width of the result
637 /// \param loBit the index of the lowest bit to set.
638 ///
639 /// \returns An APInt value with the requested bits set.
getBitsSetFrom(unsigned numBits,unsigned loBit)640 static APInt getBitsSetFrom(unsigned numBits, unsigned loBit) {
641 APInt Res(numBits, 0);
642 Res.setBitsFrom(loBit);
643 return Res;
644 }
645
646 /// Get a value with high bits set
647 ///
648 /// Constructs an APInt value that has the top hiBitsSet bits set.
649 ///
650 /// \param numBits the bitwidth of the result
651 /// \param hiBitsSet the number of high-order bits set in the result.
getHighBitsSet(unsigned numBits,unsigned hiBitsSet)652 static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet) {
653 APInt Res(numBits, 0);
654 Res.setHighBits(hiBitsSet);
655 return Res;
656 }
657
658 /// Get a value with low bits set
659 ///
660 /// Constructs an APInt value that has the bottom loBitsSet bits set.
661 ///
662 /// \param numBits the bitwidth of the result
663 /// \param loBitsSet the number of low-order bits set in the result.
getLowBitsSet(unsigned numBits,unsigned loBitsSet)664 static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet) {
665 APInt Res(numBits, 0);
666 Res.setLowBits(loBitsSet);
667 return Res;
668 }
669
670 /// Return a value containing V broadcasted over NewLen bits.
671 static APInt getSplat(unsigned NewLen, const APInt &V);
672
673 /// Determine if two APInts have the same value, after zero-extending
674 /// one of them (if needed!) to ensure that the bit-widths match.
isSameValue(const APInt & I1,const APInt & I2)675 static bool isSameValue(const APInt &I1, const APInt &I2) {
676 if (I1.getBitWidth() == I2.getBitWidth())
677 return I1 == I2;
678
679 if (I1.getBitWidth() > I2.getBitWidth())
680 return I1 == I2.zext(I1.getBitWidth());
681
682 return I1.zext(I2.getBitWidth()) == I2;
683 }
684
685 /// Overload to compute a hash_code for an APInt value.
686 friend hash_code hash_value(const APInt &Arg);
687
688 /// This function returns a pointer to the internal storage of the APInt.
689 /// This is useful for writing out the APInt in binary form without any
690 /// conversions.
getRawData()691 const uint64_t *getRawData() const {
692 if (isSingleWord())
693 return &U.VAL;
694 return &U.pVal[0];
695 }
696
697 /// @}
698 /// \name Unary Operators
699 /// @{
700
701 /// Postfix increment operator.
702 ///
703 /// Increments *this by 1.
704 ///
705 /// \returns a new APInt value representing the original value of *this.
706 const APInt operator++(int) {
707 APInt API(*this);
708 ++(*this);
709 return API;
710 }
711
712 /// Prefix increment operator.
713 ///
714 /// \returns *this incremented by one
715 APInt &operator++();
716
717 /// Postfix decrement operator.
718 ///
719 /// Decrements *this by 1.
720 ///
721 /// \returns a new APInt value representing the original value of *this.
722 const APInt operator--(int) {
723 APInt API(*this);
724 --(*this);
725 return API;
726 }
727
728 /// Prefix decrement operator.
729 ///
730 /// \returns *this decremented by one.
731 APInt &operator--();
732
733 /// Logical negation operator.
734 ///
735 /// Performs logical negation operation on this APInt.
736 ///
737 /// \returns true if *this is zero, false otherwise.
738 bool operator!() const {
739 if (isSingleWord())
740 return U.VAL == 0;
741 return countLeadingZerosSlowCase() == BitWidth;
742 }
743
744 /// @}
745 /// \name Assignment Operators
746 /// @{
747
748 /// Copy assignment operator.
749 ///
750 /// \returns *this after assignment of RHS.
751 APInt &operator=(const APInt &RHS) {
752 // If the bitwidths are the same, we can avoid mucking with memory
753 if (isSingleWord() && RHS.isSingleWord()) {
754 U.VAL = RHS.U.VAL;
755 BitWidth = RHS.BitWidth;
756 return clearUnusedBits();
757 }
758
759 AssignSlowCase(RHS);
760 return *this;
761 }
762
763 /// Move assignment operator.
764 APInt &operator=(APInt &&that) {
765 #ifdef _MSC_VER
766 // The MSVC std::shuffle implementation still does self-assignment.
767 if (this == &that)
768 return *this;
769 #endif
770 assert(this != &that && "Self-move not supported");
771 if (!isSingleWord())
772 delete[] U.pVal;
773
774 // Use memcpy so that type based alias analysis sees both VAL and pVal
775 // as modified.
776 memcpy(&U, &that.U, sizeof(U));
777
778 BitWidth = that.BitWidth;
779 that.BitWidth = 0;
780
781 return *this;
782 }
783
784 /// Assignment operator.
785 ///
786 /// The RHS value is assigned to *this. If the significant bits in RHS exceed
787 /// the bit width, the excess bits are truncated. If the bit width is larger
788 /// than 64, the value is zero filled in the unspecified high order bits.
789 ///
790 /// \returns *this after assignment of RHS value.
791 APInt &operator=(uint64_t RHS) {
792 if (isSingleWord()) {
793 U.VAL = RHS;
794 clearUnusedBits();
795 } else {
796 U.pVal[0] = RHS;
797 memset(U.pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
798 }
799 return *this;
800 }
801
802 /// Bitwise AND assignment operator.
803 ///
804 /// Performs a bitwise AND operation on this APInt and RHS. The result is
805 /// assigned to *this.
806 ///
807 /// \returns *this after ANDing with RHS.
808 APInt &operator&=(const APInt &RHS) {
809 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
810 if (isSingleWord())
811 U.VAL &= RHS.U.VAL;
812 else
813 AndAssignSlowCase(RHS);
814 return *this;
815 }
816
817 /// Bitwise AND assignment operator.
818 ///
819 /// Performs a bitwise AND operation on this APInt and RHS. RHS is
820 /// logically zero-extended or truncated to match the bit-width of
821 /// the LHS.
822 APInt &operator&=(uint64_t RHS) {
823 if (isSingleWord()) {
824 U.VAL &= RHS;
825 return *this;
826 }
827 U.pVal[0] &= RHS;
828 memset(U.pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
829 return *this;
830 }
831
832 /// Bitwise OR assignment operator.
833 ///
834 /// Performs a bitwise OR operation on this APInt and RHS. The result is
835 /// assigned *this;
836 ///
837 /// \returns *this after ORing with RHS.
838 APInt &operator|=(const APInt &RHS) {
839 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
840 if (isSingleWord())
841 U.VAL |= RHS.U.VAL;
842 else
843 OrAssignSlowCase(RHS);
844 return *this;
845 }
846
847 /// Bitwise OR assignment operator.
848 ///
849 /// Performs a bitwise OR operation on this APInt and RHS. RHS is
850 /// logically zero-extended or truncated to match the bit-width of
851 /// the LHS.
852 APInt &operator|=(uint64_t RHS) {
853 if (isSingleWord()) {
854 U.VAL |= RHS;
855 clearUnusedBits();
856 } else {
857 U.pVal[0] |= RHS;
858 }
859 return *this;
860 }
861
862 /// Bitwise XOR assignment operator.
863 ///
864 /// Performs a bitwise XOR operation on this APInt and RHS. The result is
865 /// assigned to *this.
866 ///
867 /// \returns *this after XORing with RHS.
868 APInt &operator^=(const APInt &RHS) {
869 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
870 if (isSingleWord())
871 U.VAL ^= RHS.U.VAL;
872 else
873 XorAssignSlowCase(RHS);
874 return *this;
875 }
876
877 /// Bitwise XOR assignment operator.
878 ///
879 /// Performs a bitwise XOR operation on this APInt and RHS. RHS is
880 /// logically zero-extended or truncated to match the bit-width of
881 /// the LHS.
882 APInt &operator^=(uint64_t RHS) {
883 if (isSingleWord()) {
884 U.VAL ^= RHS;
885 clearUnusedBits();
886 } else {
887 U.pVal[0] ^= RHS;
888 }
889 return *this;
890 }
891
892 /// Multiplication assignment operator.
893 ///
894 /// Multiplies this APInt by RHS and assigns the result to *this.
895 ///
896 /// \returns *this
897 APInt &operator*=(const APInt &RHS);
898 APInt &operator*=(uint64_t RHS);
899
900 /// Addition assignment operator.
901 ///
902 /// Adds RHS to *this and assigns the result to *this.
903 ///
904 /// \returns *this
905 APInt &operator+=(const APInt &RHS);
906 APInt &operator+=(uint64_t RHS);
907
908 /// Subtraction assignment operator.
909 ///
910 /// Subtracts RHS from *this and assigns the result to *this.
911 ///
912 /// \returns *this
913 APInt &operator-=(const APInt &RHS);
914 APInt &operator-=(uint64_t RHS);
915
916 /// Left-shift assignment function.
917 ///
918 /// Shifts *this left by shiftAmt and assigns the result to *this.
919 ///
920 /// \returns *this after shifting left by ShiftAmt
921 APInt &operator<<=(unsigned ShiftAmt) {
922 assert(ShiftAmt <= BitWidth && "Invalid shift amount");
923 if (isSingleWord()) {
924 if (ShiftAmt == BitWidth)
925 U.VAL = 0;
926 else
927 U.VAL <<= ShiftAmt;
928 return clearUnusedBits();
929 }
930 shlSlowCase(ShiftAmt);
931 return *this;
932 }
933
934 /// Left-shift assignment function.
935 ///
936 /// Shifts *this left by shiftAmt and assigns the result to *this.
937 ///
938 /// \returns *this after shifting left by ShiftAmt
939 APInt &operator<<=(const APInt &ShiftAmt);
940
941 /// @}
942 /// \name Binary Operators
943 /// @{
944
945 /// Multiplication operator.
946 ///
947 /// Multiplies this APInt by RHS and returns the result.
948 APInt operator*(const APInt &RHS) const;
949
950 /// Left logical shift operator.
951 ///
952 /// Shifts this APInt left by \p Bits and returns the result.
953 APInt operator<<(unsigned Bits) const { return shl(Bits); }
954
955 /// Left logical shift operator.
956 ///
957 /// Shifts this APInt left by \p Bits and returns the result.
958 APInt operator<<(const APInt &Bits) const { return shl(Bits); }
959
960 /// Arithmetic right-shift function.
961 ///
962 /// Arithmetic right-shift this APInt by shiftAmt.
ashr(unsigned ShiftAmt)963 APInt ashr(unsigned ShiftAmt) const {
964 APInt R(*this);
965 R.ashrInPlace(ShiftAmt);
966 return R;
967 }
968
969 /// Arithmetic right-shift this APInt by ShiftAmt in place.
ashrInPlace(unsigned ShiftAmt)970 void ashrInPlace(unsigned ShiftAmt) {
971 assert(ShiftAmt <= BitWidth && "Invalid shift amount");
972 if (isSingleWord()) {
973 int64_t SExtVAL = SignExtend64(U.VAL, BitWidth);
974 if (ShiftAmt == BitWidth)
975 U.VAL = SExtVAL >> (APINT_BITS_PER_WORD - 1); // Fill with sign bit.
976 else
977 U.VAL = SExtVAL >> ShiftAmt;
978 clearUnusedBits();
979 return;
980 }
981 ashrSlowCase(ShiftAmt);
982 }
983
984 /// Logical right-shift function.
985 ///
986 /// Logical right-shift this APInt by shiftAmt.
lshr(unsigned shiftAmt)987 APInt lshr(unsigned shiftAmt) const {
988 APInt R(*this);
989 R.lshrInPlace(shiftAmt);
990 return R;
991 }
992
993 /// Logical right-shift this APInt by ShiftAmt in place.
lshrInPlace(unsigned ShiftAmt)994 void lshrInPlace(unsigned ShiftAmt) {
995 assert(ShiftAmt <= BitWidth && "Invalid shift amount");
996 if (isSingleWord()) {
997 if (ShiftAmt == BitWidth)
998 U.VAL = 0;
999 else
1000 U.VAL >>= ShiftAmt;
1001 return;
1002 }
1003 lshrSlowCase(ShiftAmt);
1004 }
1005
1006 /// Left-shift function.
1007 ///
1008 /// Left-shift this APInt by shiftAmt.
shl(unsigned shiftAmt)1009 APInt shl(unsigned shiftAmt) const {
1010 APInt R(*this);
1011 R <<= shiftAmt;
1012 return R;
1013 }
1014
1015 /// Rotate left by rotateAmt.
1016 APInt rotl(unsigned rotateAmt) const;
1017
1018 /// Rotate right by rotateAmt.
1019 APInt rotr(unsigned rotateAmt) const;
1020
1021 /// Arithmetic right-shift function.
1022 ///
1023 /// Arithmetic right-shift this APInt by shiftAmt.
ashr(const APInt & ShiftAmt)1024 APInt ashr(const APInt &ShiftAmt) const {
1025 APInt R(*this);
1026 R.ashrInPlace(ShiftAmt);
1027 return R;
1028 }
1029
1030 /// Arithmetic right-shift this APInt by shiftAmt in place.
1031 void ashrInPlace(const APInt &shiftAmt);
1032
1033 /// Logical right-shift function.
1034 ///
1035 /// Logical right-shift this APInt by shiftAmt.
lshr(const APInt & ShiftAmt)1036 APInt lshr(const APInt &ShiftAmt) const {
1037 APInt R(*this);
1038 R.lshrInPlace(ShiftAmt);
1039 return R;
1040 }
1041
1042 /// Logical right-shift this APInt by ShiftAmt in place.
1043 void lshrInPlace(const APInt &ShiftAmt);
1044
1045 /// Left-shift function.
1046 ///
1047 /// Left-shift this APInt by shiftAmt.
shl(const APInt & ShiftAmt)1048 APInt shl(const APInt &ShiftAmt) const {
1049 APInt R(*this);
1050 R <<= ShiftAmt;
1051 return R;
1052 }
1053
1054 /// Rotate left by rotateAmt.
1055 APInt rotl(const APInt &rotateAmt) const;
1056
1057 /// Rotate right by rotateAmt.
1058 APInt rotr(const APInt &rotateAmt) const;
1059
1060 /// Unsigned division operation.
1061 ///
1062 /// Perform an unsigned divide operation on this APInt by RHS. Both this and
1063 /// RHS are treated as unsigned quantities for purposes of this division.
1064 ///
1065 /// \returns a new APInt value containing the division result, rounded towards
1066 /// zero.
1067 APInt udiv(const APInt &RHS) const;
1068 APInt udiv(uint64_t RHS) const;
1069
1070 /// Signed division function for APInt.
1071 ///
1072 /// Signed divide this APInt by APInt RHS.
1073 ///
1074 /// The result is rounded towards zero.
1075 APInt sdiv(const APInt &RHS) const;
1076 APInt sdiv(int64_t RHS) const;
1077
1078 /// Unsigned remainder operation.
1079 ///
1080 /// Perform an unsigned remainder operation on this APInt with RHS being the
1081 /// divisor. Both this and RHS are treated as unsigned quantities for purposes
1082 /// of this operation. Note that this is a true remainder operation and not a
1083 /// modulo operation because the sign follows the sign of the dividend which
1084 /// is *this.
1085 ///
1086 /// \returns a new APInt value containing the remainder result
1087 APInt urem(const APInt &RHS) const;
1088 uint64_t urem(uint64_t RHS) const;
1089
1090 /// Function for signed remainder operation.
1091 ///
1092 /// Signed remainder operation on APInt.
1093 APInt srem(const APInt &RHS) const;
1094 int64_t srem(int64_t RHS) const;
1095
1096 /// Dual division/remainder interface.
1097 ///
1098 /// Sometimes it is convenient to divide two APInt values and obtain both the
1099 /// quotient and remainder. This function does both operations in the same
1100 /// computation making it a little more efficient. The pair of input arguments
1101 /// may overlap with the pair of output arguments. It is safe to call
1102 /// udivrem(X, Y, X, Y), for example.
1103 static void udivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
1104 APInt &Remainder);
1105 static void udivrem(const APInt &LHS, uint64_t RHS, APInt &Quotient,
1106 uint64_t &Remainder);
1107
1108 static void sdivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
1109 APInt &Remainder);
1110 static void sdivrem(const APInt &LHS, int64_t RHS, APInt &Quotient,
1111 int64_t &Remainder);
1112
1113 // Operations that return overflow indicators.
1114 APInt sadd_ov(const APInt &RHS, bool &Overflow) const;
1115 APInt uadd_ov(const APInt &RHS, bool &Overflow) const;
1116 APInt ssub_ov(const APInt &RHS, bool &Overflow) const;
1117 APInt usub_ov(const APInt &RHS, bool &Overflow) const;
1118 APInt sdiv_ov(const APInt &RHS, bool &Overflow) const;
1119 APInt smul_ov(const APInt &RHS, bool &Overflow) const;
1120 APInt umul_ov(const APInt &RHS, bool &Overflow) const;
1121 APInt sshl_ov(const APInt &Amt, bool &Overflow) const;
1122 APInt ushl_ov(const APInt &Amt, bool &Overflow) const;
1123
1124 // Operations that saturate
1125 APInt sadd_sat(const APInt &RHS) const;
1126 APInt uadd_sat(const APInt &RHS) const;
1127 APInt ssub_sat(const APInt &RHS) const;
1128 APInt usub_sat(const APInt &RHS) const;
1129 APInt smul_sat(const APInt &RHS) const;
1130 APInt umul_sat(const APInt &RHS) const;
1131 APInt sshl_sat(const APInt &RHS) const;
1132 APInt ushl_sat(const APInt &RHS) const;
1133
1134 /// Array-indexing support.
1135 ///
1136 /// \returns the bit value at bitPosition
1137 bool operator[](unsigned bitPosition) const {
1138 assert(bitPosition < getBitWidth() && "Bit position out of bounds!");
1139 return (maskBit(bitPosition) & getWord(bitPosition)) != 0;
1140 }
1141
1142 /// @}
1143 /// \name Comparison Operators
1144 /// @{
1145
1146 /// Equality operator.
1147 ///
1148 /// Compares this APInt with RHS for the validity of the equality
1149 /// relationship.
1150 bool operator==(const APInt &RHS) const {
1151 assert(BitWidth == RHS.BitWidth && "Comparison requires equal bit widths");
1152 if (isSingleWord())
1153 return U.VAL == RHS.U.VAL;
1154 return EqualSlowCase(RHS);
1155 }
1156
1157 /// Equality operator.
1158 ///
1159 /// Compares this APInt with a uint64_t for the validity of the equality
1160 /// relationship.
1161 ///
1162 /// \returns true if *this == Val
1163 bool operator==(uint64_t Val) const {
1164 return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() == Val;
1165 }
1166
1167 /// Equality comparison.
1168 ///
1169 /// Compares this APInt with RHS for the validity of the equality
1170 /// relationship.
1171 ///
1172 /// \returns true if *this == Val
eq(const APInt & RHS)1173 bool eq(const APInt &RHS) const { return (*this) == RHS; }
1174
1175 /// Inequality operator.
1176 ///
1177 /// Compares this APInt with RHS for the validity of the inequality
1178 /// relationship.
1179 ///
1180 /// \returns true if *this != Val
1181 bool operator!=(const APInt &RHS) const { return !((*this) == RHS); }
1182
1183 /// Inequality operator.
1184 ///
1185 /// Compares this APInt with a uint64_t for the validity of the inequality
1186 /// relationship.
1187 ///
1188 /// \returns true if *this != Val
1189 bool operator!=(uint64_t Val) const { return !((*this) == Val); }
1190
1191 /// Inequality comparison
1192 ///
1193 /// Compares this APInt with RHS for the validity of the inequality
1194 /// relationship.
1195 ///
1196 /// \returns true if *this != Val
ne(const APInt & RHS)1197 bool ne(const APInt &RHS) const { return !((*this) == RHS); }
1198
1199 /// Unsigned less than comparison
1200 ///
1201 /// Regards both *this and RHS as unsigned quantities and compares them for
1202 /// the validity of the less-than relationship.
1203 ///
1204 /// \returns true if *this < RHS when both are considered unsigned.
ult(const APInt & RHS)1205 bool ult(const APInt &RHS) const { return compare(RHS) < 0; }
1206
1207 /// Unsigned less than comparison
1208 ///
1209 /// Regards both *this as an unsigned quantity and compares it with RHS for
1210 /// the validity of the less-than relationship.
1211 ///
1212 /// \returns true if *this < RHS when considered unsigned.
ult(uint64_t RHS)1213 bool ult(uint64_t RHS) const {
1214 // Only need to check active bits if not a single word.
1215 return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() < RHS;
1216 }
1217
1218 /// Signed less than comparison
1219 ///
1220 /// Regards both *this and RHS as signed quantities and compares them for
1221 /// validity of the less-than relationship.
1222 ///
1223 /// \returns true if *this < RHS when both are considered signed.
slt(const APInt & RHS)1224 bool slt(const APInt &RHS) const { return compareSigned(RHS) < 0; }
1225
1226 /// Signed less than comparison
1227 ///
1228 /// Regards both *this as a signed quantity and compares it with RHS for
1229 /// the validity of the less-than relationship.
1230 ///
1231 /// \returns true if *this < RHS when considered signed.
slt(int64_t RHS)1232 bool slt(int64_t RHS) const {
1233 return (!isSingleWord() && getMinSignedBits() > 64) ? isNegative()
1234 : getSExtValue() < RHS;
1235 }
1236
1237 /// Unsigned less or equal comparison
1238 ///
1239 /// Regards both *this and RHS as unsigned quantities and compares them for
1240 /// validity of the less-or-equal relationship.
1241 ///
1242 /// \returns true if *this <= RHS when both are considered unsigned.
ule(const APInt & RHS)1243 bool ule(const APInt &RHS) const { return compare(RHS) <= 0; }
1244
1245 /// Unsigned less or equal comparison
1246 ///
1247 /// Regards both *this as an unsigned quantity and compares it with RHS for
1248 /// the validity of the less-or-equal relationship.
1249 ///
1250 /// \returns true if *this <= RHS when considered unsigned.
ule(uint64_t RHS)1251 bool ule(uint64_t RHS) const { return !ugt(RHS); }
1252
1253 /// Signed less or equal comparison
1254 ///
1255 /// Regards both *this and RHS as signed quantities and compares them for
1256 /// validity of the less-or-equal relationship.
1257 ///
1258 /// \returns true if *this <= RHS when both are considered signed.
sle(const APInt & RHS)1259 bool sle(const APInt &RHS) const { return compareSigned(RHS) <= 0; }
1260
1261 /// Signed less or equal comparison
1262 ///
1263 /// Regards both *this as a signed quantity and compares it with RHS for the
1264 /// validity of the less-or-equal relationship.
1265 ///
1266 /// \returns true if *this <= RHS when considered signed.
sle(uint64_t RHS)1267 bool sle(uint64_t RHS) const { return !sgt(RHS); }
1268
1269 /// Unsigned greater than comparison
1270 ///
1271 /// Regards both *this and RHS as unsigned quantities and compares them for
1272 /// the validity of the greater-than relationship.
1273 ///
1274 /// \returns true if *this > RHS when both are considered unsigned.
ugt(const APInt & RHS)1275 bool ugt(const APInt &RHS) const { return !ule(RHS); }
1276
1277 /// Unsigned greater than comparison
1278 ///
1279 /// Regards both *this as an unsigned quantity and compares it with RHS for
1280 /// the validity of the greater-than relationship.
1281 ///
1282 /// \returns true if *this > RHS when considered unsigned.
ugt(uint64_t RHS)1283 bool ugt(uint64_t RHS) const {
1284 // Only need to check active bits if not a single word.
1285 return (!isSingleWord() && getActiveBits() > 64) || getZExtValue() > RHS;
1286 }
1287
1288 /// Signed greater than comparison
1289 ///
1290 /// Regards both *this and RHS as signed quantities and compares them for the
1291 /// validity of the greater-than relationship.
1292 ///
1293 /// \returns true if *this > RHS when both are considered signed.
sgt(const APInt & RHS)1294 bool sgt(const APInt &RHS) const { return !sle(RHS); }
1295
1296 /// Signed greater than comparison
1297 ///
1298 /// Regards both *this as a signed quantity and compares it with RHS for
1299 /// the validity of the greater-than relationship.
1300 ///
1301 /// \returns true if *this > RHS when considered signed.
sgt(int64_t RHS)1302 bool sgt(int64_t RHS) const {
1303 return (!isSingleWord() && getMinSignedBits() > 64) ? !isNegative()
1304 : getSExtValue() > RHS;
1305 }
1306
1307 /// Unsigned greater or equal comparison
1308 ///
1309 /// Regards both *this and RHS as unsigned quantities and compares them for
1310 /// validity of the greater-or-equal relationship.
1311 ///
1312 /// \returns true if *this >= RHS when both are considered unsigned.
uge(const APInt & RHS)1313 bool uge(const APInt &RHS) const { return !ult(RHS); }
1314
1315 /// Unsigned greater or equal comparison
1316 ///
1317 /// Regards both *this as an unsigned quantity and compares it with RHS for
1318 /// the validity of the greater-or-equal relationship.
1319 ///
1320 /// \returns true if *this >= RHS when considered unsigned.
uge(uint64_t RHS)1321 bool uge(uint64_t RHS) const { return !ult(RHS); }
1322
1323 /// Signed greater or equal comparison
1324 ///
1325 /// Regards both *this and RHS as signed quantities and compares them for
1326 /// validity of the greater-or-equal relationship.
1327 ///
1328 /// \returns true if *this >= RHS when both are considered signed.
sge(const APInt & RHS)1329 bool sge(const APInt &RHS) const { return !slt(RHS); }
1330
1331 /// Signed greater or equal comparison
1332 ///
1333 /// Regards both *this as a signed quantity and compares it with RHS for
1334 /// the validity of the greater-or-equal relationship.
1335 ///
1336 /// \returns true if *this >= RHS when considered signed.
sge(int64_t RHS)1337 bool sge(int64_t RHS) const { return !slt(RHS); }
1338
1339 /// This operation tests if there are any pairs of corresponding bits
1340 /// between this APInt and RHS that are both set.
intersects(const APInt & RHS)1341 bool intersects(const APInt &RHS) const {
1342 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
1343 if (isSingleWord())
1344 return (U.VAL & RHS.U.VAL) != 0;
1345 return intersectsSlowCase(RHS);
1346 }
1347
1348 /// This operation checks that all bits set in this APInt are also set in RHS.
isSubsetOf(const APInt & RHS)1349 bool isSubsetOf(const APInt &RHS) const {
1350 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
1351 if (isSingleWord())
1352 return (U.VAL & ~RHS.U.VAL) == 0;
1353 return isSubsetOfSlowCase(RHS);
1354 }
1355
1356 /// @}
1357 /// \name Resizing Operators
1358 /// @{
1359
1360 /// Truncate to new width.
1361 ///
1362 /// Truncate the APInt to a specified width. It is an error to specify a width
1363 /// that is greater than or equal to the current width.
1364 APInt trunc(unsigned width) const;
1365
1366 /// Truncate to new width with unsigned saturation.
1367 ///
1368 /// If the APInt, treated as unsigned integer, can be losslessly truncated to
1369 /// the new bitwidth, then return truncated APInt. Else, return max value.
1370 APInt truncUSat(unsigned width) const;
1371
1372 /// Truncate to new width with signed saturation.
1373 ///
1374 /// If this APInt, treated as signed integer, can be losslessly truncated to
1375 /// the new bitwidth, then return truncated APInt. Else, return either
1376 /// signed min value if the APInt was negative, or signed max value.
1377 APInt truncSSat(unsigned width) const;
1378
1379 /// Sign extend to a new width.
1380 ///
1381 /// This operation sign extends the APInt to a new width. If the high order
1382 /// bit is set, the fill on the left will be done with 1 bits, otherwise zero.
1383 /// It is an error to specify a width that is less than or equal to the
1384 /// current width.
1385 APInt sext(unsigned width) const;
1386
1387 /// Zero extend to a new width.
1388 ///
1389 /// This operation zero extends the APInt to a new width. The high order bits
1390 /// are filled with 0 bits. It is an error to specify a width that is less
1391 /// than or equal to the current width.
1392 APInt zext(unsigned width) const;
1393
1394 /// Sign extend or truncate to width
1395 ///
1396 /// Make this APInt have the bit width given by \p width. The value is sign
1397 /// extended, truncated, or left alone to make it that width.
1398 APInt sextOrTrunc(unsigned width) const;
1399
1400 /// Zero extend or truncate to width
1401 ///
1402 /// Make this APInt have the bit width given by \p width. The value is zero
1403 /// extended, truncated, or left alone to make it that width.
1404 APInt zextOrTrunc(unsigned width) const;
1405
1406 /// Sign extend or truncate to width
1407 ///
1408 /// Make this APInt have the bit width given by \p width. The value is sign
1409 /// extended, or left alone to make it that width.
1410 APInt sextOrSelf(unsigned width) const;
1411
1412 /// Zero extend or truncate to width
1413 ///
1414 /// Make this APInt have the bit width given by \p width. The value is zero
1415 /// extended, or left alone to make it that width.
1416 APInt zextOrSelf(unsigned width) const;
1417
1418 /// @}
1419 /// \name Bit Manipulation Operators
1420 /// @{
1421
1422 /// Set every bit to 1.
setAllBits()1423 void setAllBits() {
1424 if (isSingleWord())
1425 U.VAL = WORDTYPE_MAX;
1426 else
1427 // Set all the bits in all the words.
1428 memset(U.pVal, -1, getNumWords() * APINT_WORD_SIZE);
1429 // Clear the unused ones
1430 clearUnusedBits();
1431 }
1432
1433 /// Set a given bit to 1.
1434 ///
1435 /// Set the given bit to 1 whose position is given as "bitPosition".
setBit(unsigned BitPosition)1436 void setBit(unsigned BitPosition) {
1437 assert(BitPosition < BitWidth && "BitPosition out of range");
1438 WordType Mask = maskBit(BitPosition);
1439 if (isSingleWord())
1440 U.VAL |= Mask;
1441 else
1442 U.pVal[whichWord(BitPosition)] |= Mask;
1443 }
1444
1445 /// Set the sign bit to 1.
setSignBit()1446 void setSignBit() {
1447 setBit(BitWidth - 1);
1448 }
1449
1450 /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1.
1451 /// This function handles "wrap" case when \p loBit > \p hiBit, and calls
1452 /// setBits when \p loBit <= \p hiBit.
setBitsWithWrap(unsigned loBit,unsigned hiBit)1453 void setBitsWithWrap(unsigned loBit, unsigned hiBit) {
1454 assert(hiBit <= BitWidth && "hiBit out of range");
1455 assert(loBit <= BitWidth && "loBit out of range");
1456 if (loBit <= hiBit) {
1457 setBits(loBit, hiBit);
1458 return;
1459 }
1460 setLowBits(hiBit);
1461 setHighBits(BitWidth - loBit);
1462 }
1463
1464 /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1.
1465 /// This function handles case when \p loBit <= \p hiBit.
setBits(unsigned loBit,unsigned hiBit)1466 void setBits(unsigned loBit, unsigned hiBit) {
1467 assert(hiBit <= BitWidth && "hiBit out of range");
1468 assert(loBit <= BitWidth && "loBit out of range");
1469 assert(loBit <= hiBit && "loBit greater than hiBit");
1470 if (loBit == hiBit)
1471 return;
1472 if (loBit < APINT_BITS_PER_WORD && hiBit <= APINT_BITS_PER_WORD) {
1473 uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - (hiBit - loBit));
1474 mask <<= loBit;
1475 if (isSingleWord())
1476 U.VAL |= mask;
1477 else
1478 U.pVal[0] |= mask;
1479 } else {
1480 setBitsSlowCase(loBit, hiBit);
1481 }
1482 }
1483
1484 /// Set the top bits starting from loBit.
setBitsFrom(unsigned loBit)1485 void setBitsFrom(unsigned loBit) {
1486 return setBits(loBit, BitWidth);
1487 }
1488
1489 /// Set the bottom loBits bits.
setLowBits(unsigned loBits)1490 void setLowBits(unsigned loBits) {
1491 return setBits(0, loBits);
1492 }
1493
1494 /// Set the top hiBits bits.
setHighBits(unsigned hiBits)1495 void setHighBits(unsigned hiBits) {
1496 return setBits(BitWidth - hiBits, BitWidth);
1497 }
1498
1499 /// Set every bit to 0.
clearAllBits()1500 void clearAllBits() {
1501 if (isSingleWord())
1502 U.VAL = 0;
1503 else
1504 memset(U.pVal, 0, getNumWords() * APINT_WORD_SIZE);
1505 }
1506
1507 /// Set a given bit to 0.
1508 ///
1509 /// Set the given bit to 0 whose position is given as "bitPosition".
clearBit(unsigned BitPosition)1510 void clearBit(unsigned BitPosition) {
1511 assert(BitPosition < BitWidth && "BitPosition out of range");
1512 WordType Mask = ~maskBit(BitPosition);
1513 if (isSingleWord())
1514 U.VAL &= Mask;
1515 else
1516 U.pVal[whichWord(BitPosition)] &= Mask;
1517 }
1518
1519 /// Set bottom loBits bits to 0.
clearLowBits(unsigned loBits)1520 void clearLowBits(unsigned loBits) {
1521 assert(loBits <= BitWidth && "More bits than bitwidth");
1522 APInt Keep = getHighBitsSet(BitWidth, BitWidth - loBits);
1523 *this &= Keep;
1524 }
1525
1526 /// Set the sign bit to 0.
clearSignBit()1527 void clearSignBit() {
1528 clearBit(BitWidth - 1);
1529 }
1530
1531 /// Toggle every bit to its opposite value.
flipAllBits()1532 void flipAllBits() {
1533 if (isSingleWord()) {
1534 U.VAL ^= WORDTYPE_MAX;
1535 clearUnusedBits();
1536 } else {
1537 flipAllBitsSlowCase();
1538 }
1539 }
1540
1541 /// Toggles a given bit to its opposite value.
1542 ///
1543 /// Toggle a given bit to its opposite value whose position is given
1544 /// as "bitPosition".
1545 void flipBit(unsigned bitPosition);
1546
1547 /// Negate this APInt in place.
negate()1548 void negate() {
1549 flipAllBits();
1550 ++(*this);
1551 }
1552
1553 /// Insert the bits from a smaller APInt starting at bitPosition.
1554 void insertBits(const APInt &SubBits, unsigned bitPosition);
1555 void insertBits(uint64_t SubBits, unsigned bitPosition, unsigned numBits);
1556
1557 /// Return an APInt with the extracted bits [bitPosition,bitPosition+numBits).
1558 APInt extractBits(unsigned numBits, unsigned bitPosition) const;
1559 uint64_t extractBitsAsZExtValue(unsigned numBits, unsigned bitPosition) const;
1560
1561 /// @}
1562 /// \name Value Characterization Functions
1563 /// @{
1564
1565 /// Return the number of bits in the APInt.
getBitWidth()1566 unsigned getBitWidth() const { return BitWidth; }
1567
1568 /// Get the number of words.
1569 ///
1570 /// Here one word's bitwidth equals to that of uint64_t.
1571 ///
1572 /// \returns the number of words to hold the integer value of this APInt.
getNumWords()1573 unsigned getNumWords() const { return getNumWords(BitWidth); }
1574
1575 /// Get the number of words.
1576 ///
1577 /// *NOTE* Here one word's bitwidth equals to that of uint64_t.
1578 ///
1579 /// \returns the number of words to hold the integer value with a given bit
1580 /// width.
getNumWords(unsigned BitWidth)1581 static unsigned getNumWords(unsigned BitWidth) {
1582 return ((uint64_t)BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
1583 }
1584
1585 /// Compute the number of active bits in the value
1586 ///
1587 /// This function returns the number of active bits which is defined as the
1588 /// bit width minus the number of leading zeros. This is used in several
1589 /// computations to see how "wide" the value is.
getActiveBits()1590 unsigned getActiveBits() const { return BitWidth - countLeadingZeros(); }
1591
1592 /// Compute the number of active words in the value of this APInt.
1593 ///
1594 /// This is used in conjunction with getActiveData to extract the raw value of
1595 /// the APInt.
getActiveWords()1596 unsigned getActiveWords() const {
1597 unsigned numActiveBits = getActiveBits();
1598 return numActiveBits ? whichWord(numActiveBits - 1) + 1 : 1;
1599 }
1600
1601 /// Get the minimum bit size for this signed APInt
1602 ///
1603 /// Computes the minimum bit width for this APInt while considering it to be a
1604 /// signed (and probably negative) value. If the value is not negative, this
1605 /// function returns the same value as getActiveBits()+1. Otherwise, it
1606 /// returns the smallest bit width that will retain the negative value. For
1607 /// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so
1608 /// for -1, this function will always return 1.
getMinSignedBits()1609 unsigned getMinSignedBits() const {
1610 if (isNegative())
1611 return BitWidth - countLeadingOnes() + 1;
1612 return getActiveBits() + 1;
1613 }
1614
1615 /// Get zero extended value
1616 ///
1617 /// This method attempts to return the value of this APInt as a zero extended
1618 /// uint64_t. The bitwidth must be <= 64 or the value must fit within a
1619 /// uint64_t. Otherwise an assertion will result.
getZExtValue()1620 uint64_t getZExtValue() const {
1621 if (isSingleWord())
1622 return U.VAL;
1623 assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
1624 return U.pVal[0];
1625 }
1626
1627 /// Get sign extended value
1628 ///
1629 /// This method attempts to return the value of this APInt as a sign extended
1630 /// int64_t. The bit width must be <= 64 or the value must fit within an
1631 /// int64_t. Otherwise an assertion will result.
getSExtValue()1632 int64_t getSExtValue() const {
1633 if (isSingleWord())
1634 return SignExtend64(U.VAL, BitWidth);
1635 assert(getMinSignedBits() <= 64 && "Too many bits for int64_t");
1636 return int64_t(U.pVal[0]);
1637 }
1638
1639 /// Get bits required for string value.
1640 ///
1641 /// This method determines how many bits are required to hold the APInt
1642 /// equivalent of the string given by \p str.
1643 static unsigned getBitsNeeded(StringRef str, uint8_t radix);
1644
1645 /// The APInt version of the countLeadingZeros functions in
1646 /// MathExtras.h.
1647 ///
1648 /// It counts the number of zeros from the most significant bit to the first
1649 /// one bit.
1650 ///
1651 /// \returns BitWidth if the value is zero, otherwise returns the number of
1652 /// zeros from the most significant bit to the first one bits.
countLeadingZeros()1653 unsigned countLeadingZeros() const {
1654 if (isSingleWord()) {
1655 unsigned unusedBits = APINT_BITS_PER_WORD - BitWidth;
1656 return llvm::countLeadingZeros(U.VAL) - unusedBits;
1657 }
1658 return countLeadingZerosSlowCase();
1659 }
1660
1661 /// Count the number of leading one bits.
1662 ///
1663 /// This function is an APInt version of the countLeadingOnes
1664 /// functions in MathExtras.h. It counts the number of ones from the most
1665 /// significant bit to the first zero bit.
1666 ///
1667 /// \returns 0 if the high order bit is not set, otherwise returns the number
1668 /// of 1 bits from the most significant to the least
countLeadingOnes()1669 unsigned countLeadingOnes() const {
1670 if (isSingleWord())
1671 return llvm::countLeadingOnes(U.VAL << (APINT_BITS_PER_WORD - BitWidth));
1672 return countLeadingOnesSlowCase();
1673 }
1674
1675 /// Computes the number of leading bits of this APInt that are equal to its
1676 /// sign bit.
getNumSignBits()1677 unsigned getNumSignBits() const {
1678 return isNegative() ? countLeadingOnes() : countLeadingZeros();
1679 }
1680
1681 /// Count the number of trailing zero bits.
1682 ///
1683 /// This function is an APInt version of the countTrailingZeros
1684 /// functions in MathExtras.h. It counts the number of zeros from the least
1685 /// significant bit to the first set bit.
1686 ///
1687 /// \returns BitWidth if the value is zero, otherwise returns the number of
1688 /// zeros from the least significant bit to the first one bit.
countTrailingZeros()1689 unsigned countTrailingZeros() const {
1690 if (isSingleWord())
1691 return std::min(unsigned(llvm::countTrailingZeros(U.VAL)), BitWidth);
1692 return countTrailingZerosSlowCase();
1693 }
1694
1695 /// Count the number of trailing one bits.
1696 ///
1697 /// This function is an APInt version of the countTrailingOnes
1698 /// functions in MathExtras.h. It counts the number of ones from the least
1699 /// significant bit to the first zero bit.
1700 ///
1701 /// \returns BitWidth if the value is all ones, otherwise returns the number
1702 /// of ones from the least significant bit to the first zero bit.
countTrailingOnes()1703 unsigned countTrailingOnes() const {
1704 if (isSingleWord())
1705 return llvm::countTrailingOnes(U.VAL);
1706 return countTrailingOnesSlowCase();
1707 }
1708
1709 /// Count the number of bits set.
1710 ///
1711 /// This function is an APInt version of the countPopulation functions
1712 /// in MathExtras.h. It counts the number of 1 bits in the APInt value.
1713 ///
1714 /// \returns 0 if the value is zero, otherwise returns the number of set bits.
countPopulation()1715 unsigned countPopulation() const {
1716 if (isSingleWord())
1717 return llvm::countPopulation(U.VAL);
1718 return countPopulationSlowCase();
1719 }
1720
1721 /// @}
1722 /// \name Conversion Functions
1723 /// @{
1724 void print(raw_ostream &OS, bool isSigned) const;
1725
1726 /// Converts an APInt to a string and append it to Str. Str is commonly a
1727 /// SmallString.
1728 void toString(SmallVectorImpl<char> &Str, unsigned Radix, bool Signed,
1729 bool formatAsCLiteral = false) const;
1730
1731 /// Considers the APInt to be unsigned and converts it into a string in the
1732 /// radix given. The radix can be 2, 8, 10 16, or 36.
1733 void toStringUnsigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
1734 toString(Str, Radix, false, false);
1735 }
1736
1737 /// Considers the APInt to be signed and converts it into a string in the
1738 /// radix given. The radix can be 2, 8, 10, 16, or 36.
1739 void toStringSigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
1740 toString(Str, Radix, true, false);
1741 }
1742
1743 /// Return the APInt as a std::string.
1744 ///
1745 /// Note that this is an inefficient method. It is better to pass in a
1746 /// SmallVector/SmallString to the methods above to avoid thrashing the heap
1747 /// for the string.
1748 std::string toString(unsigned Radix, bool Signed) const;
1749
1750 /// \returns a byte-swapped representation of this APInt Value.
1751 APInt byteSwap() const;
1752
1753 /// \returns the value with the bit representation reversed of this APInt
1754 /// Value.
1755 APInt reverseBits() const;
1756
1757 /// Converts this APInt to a double value.
1758 double roundToDouble(bool isSigned) const;
1759
1760 /// Converts this unsigned APInt to a double value.
roundToDouble()1761 double roundToDouble() const { return roundToDouble(false); }
1762
1763 /// Converts this signed APInt to a double value.
signedRoundToDouble()1764 double signedRoundToDouble() const { return roundToDouble(true); }
1765
1766 /// Converts APInt bits to a double
1767 ///
1768 /// The conversion does not do a translation from integer to double, it just
1769 /// re-interprets the bits as a double. Note that it is valid to do this on
1770 /// any bit width. Exactly 64 bits will be translated.
bitsToDouble()1771 double bitsToDouble() const {
1772 return BitsToDouble(getWord(0));
1773 }
1774
1775 /// Converts APInt bits to a float
1776 ///
1777 /// The conversion does not do a translation from integer to float, it just
1778 /// re-interprets the bits as a float. Note that it is valid to do this on
1779 /// any bit width. Exactly 32 bits will be translated.
bitsToFloat()1780 float bitsToFloat() const {
1781 return BitsToFloat(static_cast<uint32_t>(getWord(0)));
1782 }
1783
1784 /// Converts a double to APInt bits.
1785 ///
1786 /// The conversion does not do a translation from double to integer, it just
1787 /// re-interprets the bits of the double.
doubleToBits(double V)1788 static APInt doubleToBits(double V) {
1789 return APInt(sizeof(double) * CHAR_BIT, DoubleToBits(V));
1790 }
1791
1792 /// Converts a float to APInt bits.
1793 ///
1794 /// The conversion does not do a translation from float to integer, it just
1795 /// re-interprets the bits of the float.
floatToBits(float V)1796 static APInt floatToBits(float V) {
1797 return APInt(sizeof(float) * CHAR_BIT, FloatToBits(V));
1798 }
1799
1800 /// @}
1801 /// \name Mathematics Operations
1802 /// @{
1803
1804 /// \returns the floor log base 2 of this APInt.
logBase2()1805 unsigned logBase2() const { return getActiveBits() - 1; }
1806
1807 /// \returns the ceil log base 2 of this APInt.
ceilLogBase2()1808 unsigned ceilLogBase2() const {
1809 APInt temp(*this);
1810 --temp;
1811 return temp.getActiveBits();
1812 }
1813
1814 /// \returns the nearest log base 2 of this APInt. Ties round up.
1815 ///
1816 /// NOTE: When we have a BitWidth of 1, we define:
1817 ///
1818 /// log2(0) = UINT32_MAX
1819 /// log2(1) = 0
1820 ///
1821 /// to get around any mathematical concerns resulting from
1822 /// referencing 2 in a space where 2 does no exist.
nearestLogBase2()1823 unsigned nearestLogBase2() const {
1824 // Special case when we have a bitwidth of 1. If VAL is 1, then we
1825 // get 0. If VAL is 0, we get WORDTYPE_MAX which gets truncated to
1826 // UINT32_MAX.
1827 if (BitWidth == 1)
1828 return U.VAL - 1;
1829
1830 // Handle the zero case.
1831 if (isNullValue())
1832 return UINT32_MAX;
1833
1834 // The non-zero case is handled by computing:
1835 //
1836 // nearestLogBase2(x) = logBase2(x) + x[logBase2(x)-1].
1837 //
1838 // where x[i] is referring to the value of the ith bit of x.
1839 unsigned lg = logBase2();
1840 return lg + unsigned((*this)[lg - 1]);
1841 }
1842
1843 /// \returns the log base 2 of this APInt if its an exact power of two, -1
1844 /// otherwise
exactLogBase2()1845 int32_t exactLogBase2() const {
1846 if (!isPowerOf2())
1847 return -1;
1848 return logBase2();
1849 }
1850
1851 /// Compute the square root
1852 APInt sqrt() const;
1853
1854 /// Get the absolute value;
1855 ///
1856 /// If *this is < 0 then return -(*this), otherwise *this;
abs()1857 APInt abs() const {
1858 if (isNegative())
1859 return -(*this);
1860 return *this;
1861 }
1862
1863 /// \returns the multiplicative inverse for a given modulo.
1864 APInt multiplicativeInverse(const APInt &modulo) const;
1865
1866 /// @}
1867 /// \name Support for division by constant
1868 /// @{
1869
1870 /// Calculate the magic number for signed division by a constant.
1871 struct ms;
1872 ms magic() const;
1873
1874 /// Calculate the magic number for unsigned division by a constant.
1875 struct mu;
1876 mu magicu(unsigned LeadingZeros = 0) const;
1877
1878 /// @}
1879 /// \name Building-block Operations for APInt and APFloat
1880 /// @{
1881
1882 // These building block operations operate on a representation of arbitrary
1883 // precision, two's-complement, bignum integer values. They should be
1884 // sufficient to implement APInt and APFloat bignum requirements. Inputs are
1885 // generally a pointer to the base of an array of integer parts, representing
1886 // an unsigned bignum, and a count of how many parts there are.
1887
1888 /// Sets the least significant part of a bignum to the input value, and zeroes
1889 /// out higher parts.
1890 static void tcSet(WordType *, WordType, unsigned);
1891
1892 /// Assign one bignum to another.
1893 static void tcAssign(WordType *, const WordType *, unsigned);
1894
1895 /// Returns true if a bignum is zero, false otherwise.
1896 static bool tcIsZero(const WordType *, unsigned);
1897
1898 /// Extract the given bit of a bignum; returns 0 or 1. Zero-based.
1899 static int tcExtractBit(const WordType *, unsigned bit);
1900
1901 /// Copy the bit vector of width srcBITS from SRC, starting at bit srcLSB, to
1902 /// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least
1903 /// significant bit of DST. All high bits above srcBITS in DST are
1904 /// zero-filled.
1905 static void tcExtract(WordType *, unsigned dstCount,
1906 const WordType *, unsigned srcBits,
1907 unsigned srcLSB);
1908
1909 /// Set the given bit of a bignum. Zero-based.
1910 static void tcSetBit(WordType *, unsigned bit);
1911
1912 /// Clear the given bit of a bignum. Zero-based.
1913 static void tcClearBit(WordType *, unsigned bit);
1914
1915 /// Returns the bit number of the least or most significant set bit of a
1916 /// number. If the input number has no bits set -1U is returned.
1917 static unsigned tcLSB(const WordType *, unsigned n);
1918 static unsigned tcMSB(const WordType *parts, unsigned n);
1919
1920 /// Negate a bignum in-place.
1921 static void tcNegate(WordType *, unsigned);
1922
1923 /// DST += RHS + CARRY where CARRY is zero or one. Returns the carry flag.
1924 static WordType tcAdd(WordType *, const WordType *,
1925 WordType carry, unsigned);
1926 /// DST += RHS. Returns the carry flag.
1927 static WordType tcAddPart(WordType *, WordType, unsigned);
1928
1929 /// DST -= RHS + CARRY where CARRY is zero or one. Returns the carry flag.
1930 static WordType tcSubtract(WordType *, const WordType *,
1931 WordType carry, unsigned);
1932 /// DST -= RHS. Returns the carry flag.
1933 static WordType tcSubtractPart(WordType *, WordType, unsigned);
1934
1935 /// DST += SRC * MULTIPLIER + PART if add is true
1936 /// DST = SRC * MULTIPLIER + PART if add is false
1937 ///
1938 /// Requires 0 <= DSTPARTS <= SRCPARTS + 1. If DST overlaps SRC they must
1939 /// start at the same point, i.e. DST == SRC.
1940 ///
1941 /// If DSTPARTS == SRC_PARTS + 1 no overflow occurs and zero is returned.
1942 /// Otherwise DST is filled with the least significant DSTPARTS parts of the
1943 /// result, and if all of the omitted higher parts were zero return zero,
1944 /// otherwise overflow occurred and return one.
1945 static int tcMultiplyPart(WordType *dst, const WordType *src,
1946 WordType multiplier, WordType carry,
1947 unsigned srcParts, unsigned dstParts,
1948 bool add);
1949
1950 /// DST = LHS * RHS, where DST has the same width as the operands and is
1951 /// filled with the least significant parts of the result. Returns one if
1952 /// overflow occurred, otherwise zero. DST must be disjoint from both
1953 /// operands.
1954 static int tcMultiply(WordType *, const WordType *, const WordType *,
1955 unsigned);
1956
1957 /// DST = LHS * RHS, where DST has width the sum of the widths of the
1958 /// operands. No overflow occurs. DST must be disjoint from both operands.
1959 static void tcFullMultiply(WordType *, const WordType *,
1960 const WordType *, unsigned, unsigned);
1961
1962 /// If RHS is zero LHS and REMAINDER are left unchanged, return one.
1963 /// Otherwise set LHS to LHS / RHS with the fractional part discarded, set
1964 /// REMAINDER to the remainder, return zero. i.e.
1965 ///
1966 /// OLD_LHS = RHS * LHS + REMAINDER
1967 ///
1968 /// SCRATCH is a bignum of the same size as the operands and result for use by
1969 /// the routine; its contents need not be initialized and are destroyed. LHS,
1970 /// REMAINDER and SCRATCH must be distinct.
1971 static int tcDivide(WordType *lhs, const WordType *rhs,
1972 WordType *remainder, WordType *scratch,
1973 unsigned parts);
1974
1975 /// Shift a bignum left Count bits. Shifted in bits are zero. There are no
1976 /// restrictions on Count.
1977 static void tcShiftLeft(WordType *, unsigned Words, unsigned Count);
1978
1979 /// Shift a bignum right Count bits. Shifted in bits are zero. There are no
1980 /// restrictions on Count.
1981 static void tcShiftRight(WordType *, unsigned Words, unsigned Count);
1982
1983 /// The obvious AND, OR and XOR and complement operations.
1984 static void tcAnd(WordType *, const WordType *, unsigned);
1985 static void tcOr(WordType *, const WordType *, unsigned);
1986 static void tcXor(WordType *, const WordType *, unsigned);
1987 static void tcComplement(WordType *, unsigned);
1988
1989 /// Comparison (unsigned) of two bignums.
1990 static int tcCompare(const WordType *, const WordType *, unsigned);
1991
1992 /// Increment a bignum in-place. Return the carry flag.
tcIncrement(WordType * dst,unsigned parts)1993 static WordType tcIncrement(WordType *dst, unsigned parts) {
1994 return tcAddPart(dst, 1, parts);
1995 }
1996
1997 /// Decrement a bignum in-place. Return the borrow flag.
tcDecrement(WordType * dst,unsigned parts)1998 static WordType tcDecrement(WordType *dst, unsigned parts) {
1999 return tcSubtractPart(dst, 1, parts);
2000 }
2001
2002 /// Set the least significant BITS and clear the rest.
2003 static void tcSetLeastSignificantBits(WordType *, unsigned, unsigned bits);
2004
2005 /// debug method
2006 void dump() const;
2007
2008 /// @}
2009 };
2010
2011 /// Magic data for optimising signed division by a constant.
2012 struct APInt::ms {
2013 APInt m; ///< magic number
2014 unsigned s; ///< shift amount
2015 };
2016
2017 /// Magic data for optimising unsigned division by a constant.
2018 struct APInt::mu {
2019 APInt m; ///< magic number
2020 bool a; ///< add indicator
2021 unsigned s; ///< shift amount
2022 };
2023
2024 inline bool operator==(uint64_t V1, const APInt &V2) { return V2 == V1; }
2025
2026 inline bool operator!=(uint64_t V1, const APInt &V2) { return V2 != V1; }
2027
2028 /// Unary bitwise complement operator.
2029 ///
2030 /// \returns an APInt that is the bitwise complement of \p v.
2031 inline APInt operator~(APInt v) {
2032 v.flipAllBits();
2033 return v;
2034 }
2035
2036 inline APInt operator&(APInt a, const APInt &b) {
2037 a &= b;
2038 return a;
2039 }
2040
2041 inline APInt operator&(const APInt &a, APInt &&b) {
2042 b &= a;
2043 return std::move(b);
2044 }
2045
2046 inline APInt operator&(APInt a, uint64_t RHS) {
2047 a &= RHS;
2048 return a;
2049 }
2050
2051 inline APInt operator&(uint64_t LHS, APInt b) {
2052 b &= LHS;
2053 return b;
2054 }
2055
2056 inline APInt operator|(APInt a, const APInt &b) {
2057 a |= b;
2058 return a;
2059 }
2060
2061 inline APInt operator|(const APInt &a, APInt &&b) {
2062 b |= a;
2063 return std::move(b);
2064 }
2065
2066 inline APInt operator|(APInt a, uint64_t RHS) {
2067 a |= RHS;
2068 return a;
2069 }
2070
2071 inline APInt operator|(uint64_t LHS, APInt b) {
2072 b |= LHS;
2073 return b;
2074 }
2075
2076 inline APInt operator^(APInt a, const APInt &b) {
2077 a ^= b;
2078 return a;
2079 }
2080
2081 inline APInt operator^(const APInt &a, APInt &&b) {
2082 b ^= a;
2083 return std::move(b);
2084 }
2085
2086 inline APInt operator^(APInt a, uint64_t RHS) {
2087 a ^= RHS;
2088 return a;
2089 }
2090
2091 inline APInt operator^(uint64_t LHS, APInt b) {
2092 b ^= LHS;
2093 return b;
2094 }
2095
2096 inline raw_ostream &operator<<(raw_ostream &OS, const APInt &I) {
2097 I.print(OS, true);
2098 return OS;
2099 }
2100
2101 inline APInt operator-(APInt v) {
2102 v.negate();
2103 return v;
2104 }
2105
2106 inline APInt operator+(APInt a, const APInt &b) {
2107 a += b;
2108 return a;
2109 }
2110
2111 inline APInt operator+(const APInt &a, APInt &&b) {
2112 b += a;
2113 return std::move(b);
2114 }
2115
2116 inline APInt operator+(APInt a, uint64_t RHS) {
2117 a += RHS;
2118 return a;
2119 }
2120
2121 inline APInt operator+(uint64_t LHS, APInt b) {
2122 b += LHS;
2123 return b;
2124 }
2125
2126 inline APInt operator-(APInt a, const APInt &b) {
2127 a -= b;
2128 return a;
2129 }
2130
2131 inline APInt operator-(const APInt &a, APInt &&b) {
2132 b.negate();
2133 b += a;
2134 return std::move(b);
2135 }
2136
2137 inline APInt operator-(APInt a, uint64_t RHS) {
2138 a -= RHS;
2139 return a;
2140 }
2141
2142 inline APInt operator-(uint64_t LHS, APInt b) {
2143 b.negate();
2144 b += LHS;
2145 return b;
2146 }
2147
2148 inline APInt operator*(APInt a, uint64_t RHS) {
2149 a *= RHS;
2150 return a;
2151 }
2152
2153 inline APInt operator*(uint64_t LHS, APInt b) {
2154 b *= LHS;
2155 return b;
2156 }
2157
2158
2159 namespace APIntOps {
2160
2161 /// Determine the smaller of two APInts considered to be signed.
smin(const APInt & A,const APInt & B)2162 inline const APInt &smin(const APInt &A, const APInt &B) {
2163 return A.slt(B) ? A : B;
2164 }
2165
2166 /// Determine the larger of two APInts considered to be signed.
smax(const APInt & A,const APInt & B)2167 inline const APInt &smax(const APInt &A, const APInt &B) {
2168 return A.sgt(B) ? A : B;
2169 }
2170
2171 /// Determine the smaller of two APInts considered to be signed.
umin(const APInt & A,const APInt & B)2172 inline const APInt &umin(const APInt &A, const APInt &B) {
2173 return A.ult(B) ? A : B;
2174 }
2175
2176 /// Determine the larger of two APInts considered to be unsigned.
umax(const APInt & A,const APInt & B)2177 inline const APInt &umax(const APInt &A, const APInt &B) {
2178 return A.ugt(B) ? A : B;
2179 }
2180
2181 /// Compute GCD of two unsigned APInt values.
2182 ///
2183 /// This function returns the greatest common divisor of the two APInt values
2184 /// using Stein's algorithm.
2185 ///
2186 /// \returns the greatest common divisor of A and B.
2187 APInt GreatestCommonDivisor(APInt A, APInt B);
2188
2189 /// Converts the given APInt to a double value.
2190 ///
2191 /// Treats the APInt as an unsigned value for conversion purposes.
RoundAPIntToDouble(const APInt & APIVal)2192 inline double RoundAPIntToDouble(const APInt &APIVal) {
2193 return APIVal.roundToDouble();
2194 }
2195
2196 /// Converts the given APInt to a double value.
2197 ///
2198 /// Treats the APInt as a signed value for conversion purposes.
RoundSignedAPIntToDouble(const APInt & APIVal)2199 inline double RoundSignedAPIntToDouble(const APInt &APIVal) {
2200 return APIVal.signedRoundToDouble();
2201 }
2202
2203 /// Converts the given APInt to a float vlalue.
RoundAPIntToFloat(const APInt & APIVal)2204 inline float RoundAPIntToFloat(const APInt &APIVal) {
2205 return float(RoundAPIntToDouble(APIVal));
2206 }
2207
2208 /// Converts the given APInt to a float value.
2209 ///
2210 /// Treats the APInt as a signed value for conversion purposes.
RoundSignedAPIntToFloat(const APInt & APIVal)2211 inline float RoundSignedAPIntToFloat(const APInt &APIVal) {
2212 return float(APIVal.signedRoundToDouble());
2213 }
2214
2215 /// Converts the given double value into a APInt.
2216 ///
2217 /// This function convert a double value to an APInt value.
2218 APInt RoundDoubleToAPInt(double Double, unsigned width);
2219
2220 /// Converts a float value into a APInt.
2221 ///
2222 /// Converts a float value into an APInt value.
RoundFloatToAPInt(float Float,unsigned width)2223 inline APInt RoundFloatToAPInt(float Float, unsigned width) {
2224 return RoundDoubleToAPInt(double(Float), width);
2225 }
2226
2227 /// Return A unsign-divided by B, rounded by the given rounding mode.
2228 APInt RoundingUDiv(const APInt &A, const APInt &B, APInt::Rounding RM);
2229
2230 /// Return A sign-divided by B, rounded by the given rounding mode.
2231 APInt RoundingSDiv(const APInt &A, const APInt &B, APInt::Rounding RM);
2232
2233 /// Let q(n) = An^2 + Bn + C, and BW = bit width of the value range
2234 /// (e.g. 32 for i32).
2235 /// This function finds the smallest number n, such that
2236 /// (a) n >= 0 and q(n) = 0, or
2237 /// (b) n >= 1 and q(n-1) and q(n), when evaluated in the set of all
2238 /// integers, belong to two different intervals [Rk, Rk+R),
2239 /// where R = 2^BW, and k is an integer.
2240 /// The idea here is to find when q(n) "overflows" 2^BW, while at the
2241 /// same time "allowing" subtraction. In unsigned modulo arithmetic a
2242 /// subtraction (treated as addition of negated numbers) would always
2243 /// count as an overflow, but here we want to allow values to decrease
2244 /// and increase as long as they are within the same interval.
2245 /// Specifically, adding of two negative numbers should not cause an
2246 /// overflow (as long as the magnitude does not exceed the bit width).
2247 /// On the other hand, given a positive number, adding a negative
2248 /// number to it can give a negative result, which would cause the
2249 /// value to go from [-2^BW, 0) to [0, 2^BW). In that sense, zero is
2250 /// treated as a special case of an overflow.
2251 ///
2252 /// This function returns None if after finding k that minimizes the
2253 /// positive solution to q(n) = kR, both solutions are contained between
2254 /// two consecutive integers.
2255 ///
2256 /// There are cases where q(n) > T, and q(n+1) < T (assuming evaluation
2257 /// in arithmetic modulo 2^BW, and treating the values as signed) by the
2258 /// virtue of *signed* overflow. This function will *not* find such an n,
2259 /// however it may find a value of n satisfying the inequalities due to
2260 /// an *unsigned* overflow (if the values are treated as unsigned).
2261 /// To find a solution for a signed overflow, treat it as a problem of
2262 /// finding an unsigned overflow with a range with of BW-1.
2263 ///
2264 /// The returned value may have a different bit width from the input
2265 /// coefficients.
2266 Optional<APInt> SolveQuadraticEquationWrap(APInt A, APInt B, APInt C,
2267 unsigned RangeWidth);
2268
2269 /// Compare two values, and if they are different, return the position of the
2270 /// most significant bit that is different in the values.
2271 Optional<unsigned> GetMostSignificantDifferentBit(const APInt &A,
2272 const APInt &B);
2273
2274 } // End of APIntOps namespace
2275
2276 // See friend declaration above. This additional declaration is required in
2277 // order to compile LLVM with IBM xlC compiler.
2278 hash_code hash_value(const APInt &Arg);
2279
2280 /// StoreIntToMemory - Fills the StoreBytes bytes of memory starting from Dst
2281 /// with the integer held in IntVal.
2282 void StoreIntToMemory(const APInt &IntVal, uint8_t *Dst, unsigned StoreBytes);
2283
2284 /// LoadIntFromMemory - Loads the integer stored in the LoadBytes bytes starting
2285 /// from Src into IntVal, which is assumed to be wide enough and to hold zero.
2286 void LoadIntFromMemory(APInt &IntVal, uint8_t *Src, unsigned LoadBytes);
2287
2288 } // namespace llvm
2289
2290 #endif
2291