File: | build/source/llvm/lib/Support/APInt.cpp |
Warning: | line 1433, column 22 The result of the right shift is undefined due to shifting by '32', which is greater or equal to the width of type 'uint32_t' |
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1 | //===-- APInt.cpp - Implement APInt class ---------------------------------===// | ||||||||
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 | // This file implements a class to represent arbitrary precision integer | ||||||||
10 | // constant values and provide a variety of arithmetic operations on them. | ||||||||
11 | // | ||||||||
12 | //===----------------------------------------------------------------------===// | ||||||||
13 | |||||||||
14 | #include "llvm/ADT/APInt.h" | ||||||||
15 | #include "llvm/ADT/ArrayRef.h" | ||||||||
16 | #include "llvm/ADT/FoldingSet.h" | ||||||||
17 | #include "llvm/ADT/Hashing.h" | ||||||||
18 | #include "llvm/ADT/SmallString.h" | ||||||||
19 | #include "llvm/ADT/StringRef.h" | ||||||||
20 | #include "llvm/ADT/bit.h" | ||||||||
21 | #include "llvm/Config/llvm-config.h" | ||||||||
22 | #include "llvm/Support/Debug.h" | ||||||||
23 | #include "llvm/Support/ErrorHandling.h" | ||||||||
24 | #include "llvm/Support/MathExtras.h" | ||||||||
25 | #include "llvm/Support/raw_ostream.h" | ||||||||
26 | #include <cmath> | ||||||||
27 | #include <optional> | ||||||||
28 | |||||||||
29 | using namespace llvm; | ||||||||
30 | |||||||||
31 | #define DEBUG_TYPE"apint" "apint" | ||||||||
32 | |||||||||
33 | /// A utility function for allocating memory, checking for allocation failures, | ||||||||
34 | /// and ensuring the contents are zeroed. | ||||||||
35 | inline static uint64_t* getClearedMemory(unsigned numWords) { | ||||||||
36 | uint64_t *result = new uint64_t[numWords]; | ||||||||
37 | memset(result, 0, numWords * sizeof(uint64_t)); | ||||||||
38 | return result; | ||||||||
39 | } | ||||||||
40 | |||||||||
41 | /// A utility function for allocating memory and checking for allocation | ||||||||
42 | /// failure. The content is not zeroed. | ||||||||
43 | inline static uint64_t* getMemory(unsigned numWords) { | ||||||||
44 | return new uint64_t[numWords]; | ||||||||
45 | } | ||||||||
46 | |||||||||
47 | /// A utility function that converts a character to a digit. | ||||||||
48 | inline static unsigned getDigit(char cdigit, uint8_t radix) { | ||||||||
49 | unsigned r; | ||||||||
50 | |||||||||
51 | if (radix == 16 || radix == 36) { | ||||||||
52 | r = cdigit - '0'; | ||||||||
53 | if (r <= 9) | ||||||||
54 | return r; | ||||||||
55 | |||||||||
56 | r = cdigit - 'A'; | ||||||||
57 | if (r <= radix - 11U) | ||||||||
58 | return r + 10; | ||||||||
59 | |||||||||
60 | r = cdigit - 'a'; | ||||||||
61 | if (r <= radix - 11U) | ||||||||
62 | return r + 10; | ||||||||
63 | |||||||||
64 | radix = 10; | ||||||||
65 | } | ||||||||
66 | |||||||||
67 | r = cdigit - '0'; | ||||||||
68 | if (r < radix) | ||||||||
69 | return r; | ||||||||
70 | |||||||||
71 | return UINT_MAX(2147483647 *2U +1U); | ||||||||
72 | } | ||||||||
73 | |||||||||
74 | |||||||||
75 | void APInt::initSlowCase(uint64_t val, bool isSigned) { | ||||||||
76 | U.pVal = getClearedMemory(getNumWords()); | ||||||||
77 | U.pVal[0] = val; | ||||||||
78 | if (isSigned && int64_t(val) < 0) | ||||||||
79 | for (unsigned i = 1; i < getNumWords(); ++i) | ||||||||
80 | U.pVal[i] = WORDTYPE_MAX; | ||||||||
81 | clearUnusedBits(); | ||||||||
82 | } | ||||||||
83 | |||||||||
84 | void APInt::initSlowCase(const APInt& that) { | ||||||||
85 | U.pVal = getMemory(getNumWords()); | ||||||||
86 | memcpy(U.pVal, that.U.pVal, getNumWords() * APINT_WORD_SIZE); | ||||||||
87 | } | ||||||||
88 | |||||||||
89 | void APInt::initFromArray(ArrayRef<uint64_t> bigVal) { | ||||||||
90 | assert(bigVal.data() && "Null pointer detected!")(static_cast <bool> (bigVal.data() && "Null pointer detected!" ) ? void (0) : __assert_fail ("bigVal.data() && \"Null pointer detected!\"" , "llvm/lib/Support/APInt.cpp", 90, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
91 | if (isSingleWord()) | ||||||||
92 | U.VAL = bigVal[0]; | ||||||||
93 | else { | ||||||||
94 | // Get memory, cleared to 0 | ||||||||
95 | U.pVal = getClearedMemory(getNumWords()); | ||||||||
96 | // Calculate the number of words to copy | ||||||||
97 | unsigned words = std::min<unsigned>(bigVal.size(), getNumWords()); | ||||||||
98 | // Copy the words from bigVal to pVal | ||||||||
99 | memcpy(U.pVal, bigVal.data(), words * APINT_WORD_SIZE); | ||||||||
100 | } | ||||||||
101 | // Make sure unused high bits are cleared | ||||||||
102 | clearUnusedBits(); | ||||||||
103 | } | ||||||||
104 | |||||||||
105 | APInt::APInt(unsigned numBits, ArrayRef<uint64_t> bigVal) : BitWidth(numBits) { | ||||||||
106 | initFromArray(bigVal); | ||||||||
107 | } | ||||||||
108 | |||||||||
109 | APInt::APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[]) | ||||||||
110 | : BitWidth(numBits) { | ||||||||
111 | initFromArray(ArrayRef(bigVal, numWords)); | ||||||||
112 | } | ||||||||
113 | |||||||||
114 | APInt::APInt(unsigned numbits, StringRef Str, uint8_t radix) | ||||||||
115 | : BitWidth(numbits) { | ||||||||
116 | fromString(numbits, Str, radix); | ||||||||
117 | } | ||||||||
118 | |||||||||
119 | void APInt::reallocate(unsigned NewBitWidth) { | ||||||||
120 | // If the number of words is the same we can just change the width and stop. | ||||||||
121 | if (getNumWords() == getNumWords(NewBitWidth)) { | ||||||||
122 | BitWidth = NewBitWidth; | ||||||||
123 | return; | ||||||||
124 | } | ||||||||
125 | |||||||||
126 | // If we have an allocation, delete it. | ||||||||
127 | if (!isSingleWord()) | ||||||||
128 | delete [] U.pVal; | ||||||||
129 | |||||||||
130 | // Update BitWidth. | ||||||||
131 | BitWidth = NewBitWidth; | ||||||||
132 | |||||||||
133 | // If we are supposed to have an allocation, create it. | ||||||||
134 | if (!isSingleWord()) | ||||||||
135 | U.pVal = getMemory(getNumWords()); | ||||||||
136 | } | ||||||||
137 | |||||||||
138 | void APInt::assignSlowCase(const APInt &RHS) { | ||||||||
139 | // Don't do anything for X = X | ||||||||
140 | if (this == &RHS) | ||||||||
141 | return; | ||||||||
142 | |||||||||
143 | // Adjust the bit width and handle allocations as necessary. | ||||||||
144 | reallocate(RHS.getBitWidth()); | ||||||||
145 | |||||||||
146 | // Copy the data. | ||||||||
147 | if (isSingleWord()) | ||||||||
148 | U.VAL = RHS.U.VAL; | ||||||||
149 | else | ||||||||
150 | memcpy(U.pVal, RHS.U.pVal, getNumWords() * APINT_WORD_SIZE); | ||||||||
151 | } | ||||||||
152 | |||||||||
153 | /// This method 'profiles' an APInt for use with FoldingSet. | ||||||||
154 | void APInt::Profile(FoldingSetNodeID& ID) const { | ||||||||
155 | ID.AddInteger(BitWidth); | ||||||||
156 | |||||||||
157 | if (isSingleWord()) { | ||||||||
158 | ID.AddInteger(U.VAL); | ||||||||
159 | return; | ||||||||
160 | } | ||||||||
161 | |||||||||
162 | unsigned NumWords = getNumWords(); | ||||||||
163 | for (unsigned i = 0; i < NumWords; ++i) | ||||||||
164 | ID.AddInteger(U.pVal[i]); | ||||||||
165 | } | ||||||||
166 | |||||||||
167 | /// Prefix increment operator. Increments the APInt by one. | ||||||||
168 | APInt& APInt::operator++() { | ||||||||
169 | if (isSingleWord()) | ||||||||
170 | ++U.VAL; | ||||||||
171 | else | ||||||||
172 | tcIncrement(U.pVal, getNumWords()); | ||||||||
173 | return clearUnusedBits(); | ||||||||
174 | } | ||||||||
175 | |||||||||
176 | /// Prefix decrement operator. Decrements the APInt by one. | ||||||||
177 | APInt& APInt::operator--() { | ||||||||
178 | if (isSingleWord()) | ||||||||
179 | --U.VAL; | ||||||||
180 | else | ||||||||
181 | tcDecrement(U.pVal, getNumWords()); | ||||||||
182 | return clearUnusedBits(); | ||||||||
183 | } | ||||||||
184 | |||||||||
185 | /// Adds the RHS APInt to this APInt. | ||||||||
186 | /// @returns this, after addition of RHS. | ||||||||
187 | /// Addition assignment operator. | ||||||||
188 | APInt& APInt::operator+=(const APInt& RHS) { | ||||||||
189 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be the same") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\"" , "llvm/lib/Support/APInt.cpp", 189, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
190 | if (isSingleWord()) | ||||||||
191 | U.VAL += RHS.U.VAL; | ||||||||
192 | else | ||||||||
193 | tcAdd(U.pVal, RHS.U.pVal, 0, getNumWords()); | ||||||||
194 | return clearUnusedBits(); | ||||||||
195 | } | ||||||||
196 | |||||||||
197 | APInt& APInt::operator+=(uint64_t RHS) { | ||||||||
198 | if (isSingleWord()) | ||||||||
199 | U.VAL += RHS; | ||||||||
200 | else | ||||||||
201 | tcAddPart(U.pVal, RHS, getNumWords()); | ||||||||
202 | return clearUnusedBits(); | ||||||||
203 | } | ||||||||
204 | |||||||||
205 | /// Subtracts the RHS APInt from this APInt | ||||||||
206 | /// @returns this, after subtraction | ||||||||
207 | /// Subtraction assignment operator. | ||||||||
208 | APInt& APInt::operator-=(const APInt& RHS) { | ||||||||
209 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be the same") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\"" , "llvm/lib/Support/APInt.cpp", 209, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
210 | if (isSingleWord()) | ||||||||
211 | U.VAL -= RHS.U.VAL; | ||||||||
212 | else | ||||||||
213 | tcSubtract(U.pVal, RHS.U.pVal, 0, getNumWords()); | ||||||||
214 | return clearUnusedBits(); | ||||||||
215 | } | ||||||||
216 | |||||||||
217 | APInt& APInt::operator-=(uint64_t RHS) { | ||||||||
218 | if (isSingleWord()) | ||||||||
219 | U.VAL -= RHS; | ||||||||
220 | else | ||||||||
221 | tcSubtractPart(U.pVal, RHS, getNumWords()); | ||||||||
222 | return clearUnusedBits(); | ||||||||
223 | } | ||||||||
224 | |||||||||
225 | APInt APInt::operator*(const APInt& RHS) const { | ||||||||
226 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be the same") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\"" , "llvm/lib/Support/APInt.cpp", 226, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
227 | if (isSingleWord()) | ||||||||
228 | return APInt(BitWidth, U.VAL * RHS.U.VAL); | ||||||||
229 | |||||||||
230 | APInt Result(getMemory(getNumWords()), getBitWidth()); | ||||||||
231 | tcMultiply(Result.U.pVal, U.pVal, RHS.U.pVal, getNumWords()); | ||||||||
232 | Result.clearUnusedBits(); | ||||||||
233 | return Result; | ||||||||
234 | } | ||||||||
235 | |||||||||
236 | void APInt::andAssignSlowCase(const APInt &RHS) { | ||||||||
237 | WordType *dst = U.pVal, *rhs = RHS.U.pVal; | ||||||||
238 | for (size_t i = 0, e = getNumWords(); i != e; ++i) | ||||||||
239 | dst[i] &= rhs[i]; | ||||||||
240 | } | ||||||||
241 | |||||||||
242 | void APInt::orAssignSlowCase(const APInt &RHS) { | ||||||||
243 | WordType *dst = U.pVal, *rhs = RHS.U.pVal; | ||||||||
244 | for (size_t i = 0, e = getNumWords(); i != e; ++i) | ||||||||
245 | dst[i] |= rhs[i]; | ||||||||
246 | } | ||||||||
247 | |||||||||
248 | void APInt::xorAssignSlowCase(const APInt &RHS) { | ||||||||
249 | WordType *dst = U.pVal, *rhs = RHS.U.pVal; | ||||||||
250 | for (size_t i = 0, e = getNumWords(); i != e; ++i) | ||||||||
251 | dst[i] ^= rhs[i]; | ||||||||
252 | } | ||||||||
253 | |||||||||
254 | APInt &APInt::operator*=(const APInt &RHS) { | ||||||||
255 | *this = *this * RHS; | ||||||||
256 | return *this; | ||||||||
257 | } | ||||||||
258 | |||||||||
259 | APInt& APInt::operator*=(uint64_t RHS) { | ||||||||
260 | if (isSingleWord()) { | ||||||||
261 | U.VAL *= RHS; | ||||||||
262 | } else { | ||||||||
263 | unsigned NumWords = getNumWords(); | ||||||||
264 | tcMultiplyPart(U.pVal, U.pVal, RHS, 0, NumWords, NumWords, false); | ||||||||
265 | } | ||||||||
266 | return clearUnusedBits(); | ||||||||
267 | } | ||||||||
268 | |||||||||
269 | bool APInt::equalSlowCase(const APInt &RHS) const { | ||||||||
270 | return std::equal(U.pVal, U.pVal + getNumWords(), RHS.U.pVal); | ||||||||
271 | } | ||||||||
272 | |||||||||
273 | int APInt::compare(const APInt& RHS) const { | ||||||||
274 | assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be same for comparison") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be same for comparison\"" , "llvm/lib/Support/APInt.cpp", 274, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
275 | if (isSingleWord()) | ||||||||
276 | return U.VAL < RHS.U.VAL ? -1 : U.VAL > RHS.U.VAL; | ||||||||
277 | |||||||||
278 | return tcCompare(U.pVal, RHS.U.pVal, getNumWords()); | ||||||||
279 | } | ||||||||
280 | |||||||||
281 | int APInt::compareSigned(const APInt& RHS) const { | ||||||||
282 | assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be same for comparison") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be same for comparison\"" , "llvm/lib/Support/APInt.cpp", 282, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
283 | if (isSingleWord()) { | ||||||||
284 | int64_t lhsSext = SignExtend64(U.VAL, BitWidth); | ||||||||
285 | int64_t rhsSext = SignExtend64(RHS.U.VAL, BitWidth); | ||||||||
286 | return lhsSext < rhsSext ? -1 : lhsSext > rhsSext; | ||||||||
287 | } | ||||||||
288 | |||||||||
289 | bool lhsNeg = isNegative(); | ||||||||
290 | bool rhsNeg = RHS.isNegative(); | ||||||||
291 | |||||||||
292 | // If the sign bits don't match, then (LHS < RHS) if LHS is negative | ||||||||
293 | if (lhsNeg != rhsNeg) | ||||||||
294 | return lhsNeg ? -1 : 1; | ||||||||
295 | |||||||||
296 | // Otherwise we can just use an unsigned comparison, because even negative | ||||||||
297 | // numbers compare correctly this way if both have the same signed-ness. | ||||||||
298 | return tcCompare(U.pVal, RHS.U.pVal, getNumWords()); | ||||||||
299 | } | ||||||||
300 | |||||||||
301 | void APInt::setBitsSlowCase(unsigned loBit, unsigned hiBit) { | ||||||||
302 | unsigned loWord = whichWord(loBit); | ||||||||
303 | unsigned hiWord = whichWord(hiBit); | ||||||||
304 | |||||||||
305 | // Create an initial mask for the low word with zeros below loBit. | ||||||||
306 | uint64_t loMask = WORDTYPE_MAX << whichBit(loBit); | ||||||||
307 | |||||||||
308 | // If hiBit is not aligned, we need a high mask. | ||||||||
309 | unsigned hiShiftAmt = whichBit(hiBit); | ||||||||
310 | if (hiShiftAmt != 0) { | ||||||||
311 | // Create a high mask with zeros above hiBit. | ||||||||
312 | uint64_t hiMask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - hiShiftAmt); | ||||||||
313 | // If loWord and hiWord are equal, then we combine the masks. Otherwise, | ||||||||
314 | // set the bits in hiWord. | ||||||||
315 | if (hiWord == loWord) | ||||||||
316 | loMask &= hiMask; | ||||||||
317 | else | ||||||||
318 | U.pVal[hiWord] |= hiMask; | ||||||||
319 | } | ||||||||
320 | // Apply the mask to the low word. | ||||||||
321 | U.pVal[loWord] |= loMask; | ||||||||
322 | |||||||||
323 | // Fill any words between loWord and hiWord with all ones. | ||||||||
324 | for (unsigned word = loWord + 1; word < hiWord; ++word) | ||||||||
325 | U.pVal[word] = WORDTYPE_MAX; | ||||||||
326 | } | ||||||||
327 | |||||||||
328 | // Complement a bignum in-place. | ||||||||
329 | static void tcComplement(APInt::WordType *dst, unsigned parts) { | ||||||||
330 | for (unsigned i = 0; i < parts; i++) | ||||||||
331 | dst[i] = ~dst[i]; | ||||||||
332 | } | ||||||||
333 | |||||||||
334 | /// Toggle every bit to its opposite value. | ||||||||
335 | void APInt::flipAllBitsSlowCase() { | ||||||||
336 | tcComplement(U.pVal, getNumWords()); | ||||||||
337 | clearUnusedBits(); | ||||||||
338 | } | ||||||||
339 | |||||||||
340 | /// Concatenate the bits from "NewLSB" onto the bottom of *this. This is | ||||||||
341 | /// equivalent to: | ||||||||
342 | /// (this->zext(NewWidth) << NewLSB.getBitWidth()) | NewLSB.zext(NewWidth) | ||||||||
343 | /// In the slow case, we know the result is large. | ||||||||
344 | APInt APInt::concatSlowCase(const APInt &NewLSB) const { | ||||||||
345 | unsigned NewWidth = getBitWidth() + NewLSB.getBitWidth(); | ||||||||
346 | APInt Result = NewLSB.zext(NewWidth); | ||||||||
347 | Result.insertBits(*this, NewLSB.getBitWidth()); | ||||||||
348 | return Result; | ||||||||
349 | } | ||||||||
350 | |||||||||
351 | /// Toggle a given bit to its opposite value whose position is given | ||||||||
352 | /// as "bitPosition". | ||||||||
353 | /// Toggles a given bit to its opposite value. | ||||||||
354 | void APInt::flipBit(unsigned bitPosition) { | ||||||||
355 | assert(bitPosition < BitWidth && "Out of the bit-width range!")(static_cast <bool> (bitPosition < BitWidth && "Out of the bit-width range!") ? void (0) : __assert_fail ("bitPosition < BitWidth && \"Out of the bit-width range!\"" , "llvm/lib/Support/APInt.cpp", 355, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
356 | setBitVal(bitPosition, !(*this)[bitPosition]); | ||||||||
357 | } | ||||||||
358 | |||||||||
359 | void APInt::insertBits(const APInt &subBits, unsigned bitPosition) { | ||||||||
360 | unsigned subBitWidth = subBits.getBitWidth(); | ||||||||
361 | assert((subBitWidth + bitPosition) <= BitWidth && "Illegal bit insertion")(static_cast <bool> ((subBitWidth + bitPosition) <= BitWidth && "Illegal bit insertion") ? void (0) : __assert_fail ("(subBitWidth + bitPosition) <= BitWidth && \"Illegal bit insertion\"" , "llvm/lib/Support/APInt.cpp", 361, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
362 | |||||||||
363 | // inserting no bits is a noop. | ||||||||
364 | if (subBitWidth == 0) | ||||||||
365 | return; | ||||||||
366 | |||||||||
367 | // Insertion is a direct copy. | ||||||||
368 | if (subBitWidth == BitWidth) { | ||||||||
369 | *this = subBits; | ||||||||
370 | return; | ||||||||
371 | } | ||||||||
372 | |||||||||
373 | // Single word result can be done as a direct bitmask. | ||||||||
374 | if (isSingleWord()) { | ||||||||
375 | uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - subBitWidth); | ||||||||
376 | U.VAL &= ~(mask << bitPosition); | ||||||||
377 | U.VAL |= (subBits.U.VAL << bitPosition); | ||||||||
378 | return; | ||||||||
379 | } | ||||||||
380 | |||||||||
381 | unsigned loBit = whichBit(bitPosition); | ||||||||
382 | unsigned loWord = whichWord(bitPosition); | ||||||||
383 | unsigned hi1Word = whichWord(bitPosition + subBitWidth - 1); | ||||||||
384 | |||||||||
385 | // Insertion within a single word can be done as a direct bitmask. | ||||||||
386 | if (loWord == hi1Word) { | ||||||||
387 | uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - subBitWidth); | ||||||||
388 | U.pVal[loWord] &= ~(mask << loBit); | ||||||||
389 | U.pVal[loWord] |= (subBits.U.VAL << loBit); | ||||||||
390 | return; | ||||||||
391 | } | ||||||||
392 | |||||||||
393 | // Insert on word boundaries. | ||||||||
394 | if (loBit == 0) { | ||||||||
395 | // Direct copy whole words. | ||||||||
396 | unsigned numWholeSubWords = subBitWidth / APINT_BITS_PER_WORD; | ||||||||
397 | memcpy(U.pVal + loWord, subBits.getRawData(), | ||||||||
398 | numWholeSubWords * APINT_WORD_SIZE); | ||||||||
399 | |||||||||
400 | // Mask+insert remaining bits. | ||||||||
401 | unsigned remainingBits = subBitWidth % APINT_BITS_PER_WORD; | ||||||||
402 | if (remainingBits != 0) { | ||||||||
403 | uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - remainingBits); | ||||||||
404 | U.pVal[hi1Word] &= ~mask; | ||||||||
405 | U.pVal[hi1Word] |= subBits.getWord(subBitWidth - 1); | ||||||||
406 | } | ||||||||
407 | return; | ||||||||
408 | } | ||||||||
409 | |||||||||
410 | // General case - set/clear individual bits in dst based on src. | ||||||||
411 | // TODO - there is scope for optimization here, but at the moment this code | ||||||||
412 | // path is barely used so prefer readability over performance. | ||||||||
413 | for (unsigned i = 0; i != subBitWidth; ++i) | ||||||||
414 | setBitVal(bitPosition + i, subBits[i]); | ||||||||
415 | } | ||||||||
416 | |||||||||
417 | void APInt::insertBits(uint64_t subBits, unsigned bitPosition, unsigned numBits) { | ||||||||
418 | uint64_t maskBits = maskTrailingOnes<uint64_t>(numBits); | ||||||||
419 | subBits &= maskBits; | ||||||||
420 | if (isSingleWord()) { | ||||||||
421 | U.VAL &= ~(maskBits << bitPosition); | ||||||||
422 | U.VAL |= subBits << bitPosition; | ||||||||
423 | return; | ||||||||
424 | } | ||||||||
425 | |||||||||
426 | unsigned loBit = whichBit(bitPosition); | ||||||||
427 | unsigned loWord = whichWord(bitPosition); | ||||||||
428 | unsigned hiWord = whichWord(bitPosition + numBits - 1); | ||||||||
429 | if (loWord == hiWord) { | ||||||||
430 | U.pVal[loWord] &= ~(maskBits << loBit); | ||||||||
431 | U.pVal[loWord] |= subBits << loBit; | ||||||||
432 | return; | ||||||||
433 | } | ||||||||
434 | |||||||||
435 | static_assert(8 * sizeof(WordType) <= 64, "This code assumes only two words affected"); | ||||||||
436 | unsigned wordBits = 8 * sizeof(WordType); | ||||||||
437 | U.pVal[loWord] &= ~(maskBits << loBit); | ||||||||
438 | U.pVal[loWord] |= subBits << loBit; | ||||||||
439 | |||||||||
440 | U.pVal[hiWord] &= ~(maskBits >> (wordBits - loBit)); | ||||||||
441 | U.pVal[hiWord] |= subBits >> (wordBits - loBit); | ||||||||
442 | } | ||||||||
443 | |||||||||
444 | APInt APInt::extractBits(unsigned numBits, unsigned bitPosition) const { | ||||||||
445 | assert(bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth &&(static_cast <bool> (bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && "Illegal bit extraction" ) ? void (0) : __assert_fail ("bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && \"Illegal bit extraction\"" , "llvm/lib/Support/APInt.cpp", 446, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
446 | "Illegal bit extraction")(static_cast <bool> (bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && "Illegal bit extraction" ) ? void (0) : __assert_fail ("bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && \"Illegal bit extraction\"" , "llvm/lib/Support/APInt.cpp", 446, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
447 | |||||||||
448 | if (isSingleWord()) | ||||||||
449 | return APInt(numBits, U.VAL >> bitPosition); | ||||||||
450 | |||||||||
451 | unsigned loBit = whichBit(bitPosition); | ||||||||
452 | unsigned loWord = whichWord(bitPosition); | ||||||||
453 | unsigned hiWord = whichWord(bitPosition + numBits - 1); | ||||||||
454 | |||||||||
455 | // Single word result extracting bits from a single word source. | ||||||||
456 | if (loWord == hiWord) | ||||||||
457 | return APInt(numBits, U.pVal[loWord] >> loBit); | ||||||||
458 | |||||||||
459 | // Extracting bits that start on a source word boundary can be done | ||||||||
460 | // as a fast memory copy. | ||||||||
461 | if (loBit == 0) | ||||||||
462 | return APInt(numBits, ArrayRef(U.pVal + loWord, 1 + hiWord - loWord)); | ||||||||
463 | |||||||||
464 | // General case - shift + copy source words directly into place. | ||||||||
465 | APInt Result(numBits, 0); | ||||||||
466 | unsigned NumSrcWords = getNumWords(); | ||||||||
467 | unsigned NumDstWords = Result.getNumWords(); | ||||||||
468 | |||||||||
469 | uint64_t *DestPtr = Result.isSingleWord() ? &Result.U.VAL : Result.U.pVal; | ||||||||
470 | for (unsigned word = 0; word < NumDstWords; ++word) { | ||||||||
471 | uint64_t w0 = U.pVal[loWord + word]; | ||||||||
472 | uint64_t w1 = | ||||||||
473 | (loWord + word + 1) < NumSrcWords ? U.pVal[loWord + word + 1] : 0; | ||||||||
474 | DestPtr[word] = (w0 >> loBit) | (w1 << (APINT_BITS_PER_WORD - loBit)); | ||||||||
475 | } | ||||||||
476 | |||||||||
477 | return Result.clearUnusedBits(); | ||||||||
478 | } | ||||||||
479 | |||||||||
480 | uint64_t APInt::extractBitsAsZExtValue(unsigned numBits, | ||||||||
481 | unsigned bitPosition) const { | ||||||||
482 | assert(numBits > 0 && "Can't extract zero bits")(static_cast <bool> (numBits > 0 && "Can't extract zero bits" ) ? void (0) : __assert_fail ("numBits > 0 && \"Can't extract zero bits\"" , "llvm/lib/Support/APInt.cpp", 482, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
483 | assert(bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth &&(static_cast <bool> (bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && "Illegal bit extraction" ) ? void (0) : __assert_fail ("bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && \"Illegal bit extraction\"" , "llvm/lib/Support/APInt.cpp", 484, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
484 | "Illegal bit extraction")(static_cast <bool> (bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && "Illegal bit extraction" ) ? void (0) : __assert_fail ("bitPosition < BitWidth && (numBits + bitPosition) <= BitWidth && \"Illegal bit extraction\"" , "llvm/lib/Support/APInt.cpp", 484, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
485 | assert(numBits <= 64 && "Illegal bit extraction")(static_cast <bool> (numBits <= 64 && "Illegal bit extraction" ) ? void (0) : __assert_fail ("numBits <= 64 && \"Illegal bit extraction\"" , "llvm/lib/Support/APInt.cpp", 485, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
486 | |||||||||
487 | uint64_t maskBits = maskTrailingOnes<uint64_t>(numBits); | ||||||||
488 | if (isSingleWord()) | ||||||||
489 | return (U.VAL >> bitPosition) & maskBits; | ||||||||
490 | |||||||||
491 | unsigned loBit = whichBit(bitPosition); | ||||||||
492 | unsigned loWord = whichWord(bitPosition); | ||||||||
493 | unsigned hiWord = whichWord(bitPosition + numBits - 1); | ||||||||
494 | if (loWord == hiWord) | ||||||||
495 | return (U.pVal[loWord] >> loBit) & maskBits; | ||||||||
496 | |||||||||
497 | static_assert(8 * sizeof(WordType) <= 64, "This code assumes only two words affected"); | ||||||||
498 | unsigned wordBits = 8 * sizeof(WordType); | ||||||||
499 | uint64_t retBits = U.pVal[loWord] >> loBit; | ||||||||
500 | retBits |= U.pVal[hiWord] << (wordBits - loBit); | ||||||||
501 | retBits &= maskBits; | ||||||||
502 | return retBits; | ||||||||
503 | } | ||||||||
504 | |||||||||
505 | unsigned APInt::getSufficientBitsNeeded(StringRef Str, uint8_t Radix) { | ||||||||
506 | assert(!Str.empty() && "Invalid string length")(static_cast <bool> (!Str.empty() && "Invalid string length" ) ? void (0) : __assert_fail ("!Str.empty() && \"Invalid string length\"" , "llvm/lib/Support/APInt.cpp", 506, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
507 | size_t StrLen = Str.size(); | ||||||||
508 | |||||||||
509 | // Each computation below needs to know if it's negative. | ||||||||
510 | unsigned IsNegative = false; | ||||||||
511 | if (Str[0] == '-' || Str[0] == '+') { | ||||||||
512 | IsNegative = Str[0] == '-'; | ||||||||
513 | StrLen--; | ||||||||
514 | assert(StrLen && "String is only a sign, needs a value.")(static_cast <bool> (StrLen && "String is only a sign, needs a value." ) ? void (0) : __assert_fail ("StrLen && \"String is only a sign, needs a value.\"" , "llvm/lib/Support/APInt.cpp", 514, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
515 | } | ||||||||
516 | |||||||||
517 | // For radixes of power-of-two values, the bits required is accurately and | ||||||||
518 | // easily computed. | ||||||||
519 | if (Radix == 2) | ||||||||
520 | return StrLen + IsNegative; | ||||||||
521 | if (Radix == 8) | ||||||||
522 | return StrLen * 3 + IsNegative; | ||||||||
523 | if (Radix == 16) | ||||||||
524 | return StrLen * 4 + IsNegative; | ||||||||
525 | |||||||||
526 | // Compute a sufficient number of bits that is always large enough but might | ||||||||
527 | // be too large. This avoids the assertion in the constructor. This | ||||||||
528 | // calculation doesn't work appropriately for the numbers 0-9, so just use 4 | ||||||||
529 | // bits in that case. | ||||||||
530 | if (Radix == 10) | ||||||||
531 | return (StrLen == 1 ? 4 : StrLen * 64 / 18) + IsNegative; | ||||||||
532 | |||||||||
533 | assert(Radix == 36)(static_cast <bool> (Radix == 36) ? void (0) : __assert_fail ("Radix == 36", "llvm/lib/Support/APInt.cpp", 533, __extension__ __PRETTY_FUNCTION__)); | ||||||||
534 | return (StrLen == 1 ? 7 : StrLen * 16 / 3) + IsNegative; | ||||||||
535 | } | ||||||||
536 | |||||||||
537 | unsigned APInt::getBitsNeeded(StringRef str, uint8_t radix) { | ||||||||
538 | // Compute a sufficient number of bits that is always large enough but might | ||||||||
539 | // be too large. | ||||||||
540 | unsigned sufficient = getSufficientBitsNeeded(str, radix); | ||||||||
541 | |||||||||
542 | // For bases 2, 8, and 16, the sufficient number of bits is exact and we can | ||||||||
543 | // return the value directly. For bases 10 and 36, we need to do extra work. | ||||||||
544 | if (radix == 2 || radix == 8 || radix == 16) | ||||||||
545 | return sufficient; | ||||||||
546 | |||||||||
547 | // This is grossly inefficient but accurate. We could probably do something | ||||||||
548 | // with a computation of roughly slen*64/20 and then adjust by the value of | ||||||||
549 | // the first few digits. But, I'm not sure how accurate that could be. | ||||||||
550 | size_t slen = str.size(); | ||||||||
551 | |||||||||
552 | // Each computation below needs to know if it's negative. | ||||||||
553 | StringRef::iterator p = str.begin(); | ||||||||
554 | unsigned isNegative = *p == '-'; | ||||||||
555 | if (*p == '-' || *p == '+') { | ||||||||
556 | p++; | ||||||||
557 | slen--; | ||||||||
558 | assert(slen && "String is only a sign, needs a value.")(static_cast <bool> (slen && "String is only a sign, needs a value." ) ? void (0) : __assert_fail ("slen && \"String is only a sign, needs a value.\"" , "llvm/lib/Support/APInt.cpp", 558, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
559 | } | ||||||||
560 | |||||||||
561 | |||||||||
562 | // Convert to the actual binary value. | ||||||||
563 | APInt tmp(sufficient, StringRef(p, slen), radix); | ||||||||
564 | |||||||||
565 | // Compute how many bits are required. If the log is infinite, assume we need | ||||||||
566 | // just bit. If the log is exact and value is negative, then the value is | ||||||||
567 | // MinSignedValue with (log + 1) bits. | ||||||||
568 | unsigned log = tmp.logBase2(); | ||||||||
569 | if (log == (unsigned)-1) { | ||||||||
570 | return isNegative + 1; | ||||||||
571 | } else if (isNegative && tmp.isPowerOf2()) { | ||||||||
572 | return isNegative + log; | ||||||||
573 | } else { | ||||||||
574 | return isNegative + log + 1; | ||||||||
575 | } | ||||||||
576 | } | ||||||||
577 | |||||||||
578 | hash_code llvm::hash_value(const APInt &Arg) { | ||||||||
579 | if (Arg.isSingleWord()) | ||||||||
580 | return hash_combine(Arg.BitWidth, Arg.U.VAL); | ||||||||
581 | |||||||||
582 | return hash_combine( | ||||||||
583 | Arg.BitWidth, | ||||||||
584 | hash_combine_range(Arg.U.pVal, Arg.U.pVal + Arg.getNumWords())); | ||||||||
585 | } | ||||||||
586 | |||||||||
587 | unsigned DenseMapInfo<APInt, void>::getHashValue(const APInt &Key) { | ||||||||
588 | return static_cast<unsigned>(hash_value(Key)); | ||||||||
589 | } | ||||||||
590 | |||||||||
591 | bool APInt::isSplat(unsigned SplatSizeInBits) const { | ||||||||
592 | assert(getBitWidth() % SplatSizeInBits == 0 &&(static_cast <bool> (getBitWidth() % SplatSizeInBits == 0 && "SplatSizeInBits must divide width!") ? void (0 ) : __assert_fail ("getBitWidth() % SplatSizeInBits == 0 && \"SplatSizeInBits must divide width!\"" , "llvm/lib/Support/APInt.cpp", 593, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
593 | "SplatSizeInBits must divide width!")(static_cast <bool> (getBitWidth() % SplatSizeInBits == 0 && "SplatSizeInBits must divide width!") ? void (0 ) : __assert_fail ("getBitWidth() % SplatSizeInBits == 0 && \"SplatSizeInBits must divide width!\"" , "llvm/lib/Support/APInt.cpp", 593, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
594 | // We can check that all parts of an integer are equal by making use of a | ||||||||
595 | // little trick: rotate and check if it's still the same value. | ||||||||
596 | return *this == rotl(SplatSizeInBits); | ||||||||
597 | } | ||||||||
598 | |||||||||
599 | /// This function returns the high "numBits" bits of this APInt. | ||||||||
600 | APInt APInt::getHiBits(unsigned numBits) const { | ||||||||
601 | return this->lshr(BitWidth - numBits); | ||||||||
602 | } | ||||||||
603 | |||||||||
604 | /// This function returns the low "numBits" bits of this APInt. | ||||||||
605 | APInt APInt::getLoBits(unsigned numBits) const { | ||||||||
606 | APInt Result(getLowBitsSet(BitWidth, numBits)); | ||||||||
607 | Result &= *this; | ||||||||
608 | return Result; | ||||||||
609 | } | ||||||||
610 | |||||||||
611 | /// Return a value containing V broadcasted over NewLen bits. | ||||||||
612 | APInt APInt::getSplat(unsigned NewLen, const APInt &V) { | ||||||||
613 | assert(NewLen >= V.getBitWidth() && "Can't splat to smaller bit width!")(static_cast <bool> (NewLen >= V.getBitWidth() && "Can't splat to smaller bit width!") ? void (0) : __assert_fail ("NewLen >= V.getBitWidth() && \"Can't splat to smaller bit width!\"" , "llvm/lib/Support/APInt.cpp", 613, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
614 | |||||||||
615 | APInt Val = V.zext(NewLen); | ||||||||
616 | for (unsigned I = V.getBitWidth(); I < NewLen; I <<= 1) | ||||||||
617 | Val |= Val << I; | ||||||||
618 | |||||||||
619 | return Val; | ||||||||
620 | } | ||||||||
621 | |||||||||
622 | unsigned APInt::countLeadingZerosSlowCase() const { | ||||||||
623 | unsigned Count = 0; | ||||||||
624 | for (int i = getNumWords()-1; i >= 0; --i) { | ||||||||
625 | uint64_t V = U.pVal[i]; | ||||||||
626 | if (V == 0) | ||||||||
627 | Count += APINT_BITS_PER_WORD; | ||||||||
628 | else { | ||||||||
629 | Count += llvm::countl_zero(V); | ||||||||
630 | break; | ||||||||
631 | } | ||||||||
632 | } | ||||||||
633 | // Adjust for unused bits in the most significant word (they are zero). | ||||||||
634 | unsigned Mod = BitWidth % APINT_BITS_PER_WORD; | ||||||||
635 | Count -= Mod > 0 ? APINT_BITS_PER_WORD - Mod : 0; | ||||||||
636 | return Count; | ||||||||
637 | } | ||||||||
638 | |||||||||
639 | unsigned APInt::countLeadingOnesSlowCase() const { | ||||||||
640 | unsigned highWordBits = BitWidth % APINT_BITS_PER_WORD; | ||||||||
641 | unsigned shift; | ||||||||
642 | if (!highWordBits) { | ||||||||
643 | highWordBits = APINT_BITS_PER_WORD; | ||||||||
644 | shift = 0; | ||||||||
645 | } else { | ||||||||
646 | shift = APINT_BITS_PER_WORD - highWordBits; | ||||||||
647 | } | ||||||||
648 | int i = getNumWords() - 1; | ||||||||
649 | unsigned Count = llvm::countl_one(U.pVal[i] << shift); | ||||||||
650 | if (Count == highWordBits) { | ||||||||
651 | for (i--; i >= 0; --i) { | ||||||||
652 | if (U.pVal[i] == WORDTYPE_MAX) | ||||||||
653 | Count += APINT_BITS_PER_WORD; | ||||||||
654 | else { | ||||||||
655 | Count += llvm::countl_one(U.pVal[i]); | ||||||||
656 | break; | ||||||||
657 | } | ||||||||
658 | } | ||||||||
659 | } | ||||||||
660 | return Count; | ||||||||
661 | } | ||||||||
662 | |||||||||
663 | unsigned APInt::countTrailingZerosSlowCase() const { | ||||||||
664 | unsigned Count = 0; | ||||||||
665 | unsigned i = 0; | ||||||||
666 | for (; i < getNumWords() && U.pVal[i] == 0; ++i) | ||||||||
667 | Count += APINT_BITS_PER_WORD; | ||||||||
668 | if (i < getNumWords()) | ||||||||
669 | Count += llvm::countr_zero(U.pVal[i]); | ||||||||
670 | return std::min(Count, BitWidth); | ||||||||
671 | } | ||||||||
672 | |||||||||
673 | unsigned APInt::countTrailingOnesSlowCase() const { | ||||||||
674 | unsigned Count = 0; | ||||||||
675 | unsigned i = 0; | ||||||||
676 | for (; i < getNumWords() && U.pVal[i] == WORDTYPE_MAX; ++i) | ||||||||
677 | Count += APINT_BITS_PER_WORD; | ||||||||
678 | if (i < getNumWords()) | ||||||||
679 | Count += llvm::countr_one(U.pVal[i]); | ||||||||
680 | assert(Count <= BitWidth)(static_cast <bool> (Count <= BitWidth) ? void (0) : __assert_fail ("Count <= BitWidth", "llvm/lib/Support/APInt.cpp" , 680, __extension__ __PRETTY_FUNCTION__)); | ||||||||
681 | return Count; | ||||||||
682 | } | ||||||||
683 | |||||||||
684 | unsigned APInt::countPopulationSlowCase() const { | ||||||||
685 | unsigned Count = 0; | ||||||||
686 | for (unsigned i = 0; i < getNumWords(); ++i) | ||||||||
687 | Count += llvm::popcount(U.pVal[i]); | ||||||||
688 | return Count; | ||||||||
689 | } | ||||||||
690 | |||||||||
691 | bool APInt::intersectsSlowCase(const APInt &RHS) const { | ||||||||
692 | for (unsigned i = 0, e = getNumWords(); i != e; ++i) | ||||||||
693 | if ((U.pVal[i] & RHS.U.pVal[i]) != 0) | ||||||||
694 | return true; | ||||||||
695 | |||||||||
696 | return false; | ||||||||
697 | } | ||||||||
698 | |||||||||
699 | bool APInt::isSubsetOfSlowCase(const APInt &RHS) const { | ||||||||
700 | for (unsigned i = 0, e = getNumWords(); i != e; ++i) | ||||||||
701 | if ((U.pVal[i] & ~RHS.U.pVal[i]) != 0) | ||||||||
702 | return false; | ||||||||
703 | |||||||||
704 | return true; | ||||||||
705 | } | ||||||||
706 | |||||||||
707 | APInt APInt::byteSwap() const { | ||||||||
708 | assert(BitWidth >= 16 && BitWidth % 8 == 0 && "Cannot byteswap!")(static_cast <bool> (BitWidth >= 16 && BitWidth % 8 == 0 && "Cannot byteswap!") ? void (0) : __assert_fail ("BitWidth >= 16 && BitWidth % 8 == 0 && \"Cannot byteswap!\"" , "llvm/lib/Support/APInt.cpp", 708, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
709 | if (BitWidth == 16) | ||||||||
710 | return APInt(BitWidth, llvm::byteswap<uint16_t>(U.VAL)); | ||||||||
711 | if (BitWidth == 32) | ||||||||
712 | return APInt(BitWidth, llvm::byteswap<uint32_t>(U.VAL)); | ||||||||
713 | if (BitWidth <= 64) { | ||||||||
714 | uint64_t Tmp1 = llvm::byteswap<uint64_t>(U.VAL); | ||||||||
715 | Tmp1 >>= (64 - BitWidth); | ||||||||
716 | return APInt(BitWidth, Tmp1); | ||||||||
717 | } | ||||||||
718 | |||||||||
719 | APInt Result(getNumWords() * APINT_BITS_PER_WORD, 0); | ||||||||
720 | for (unsigned I = 0, N = getNumWords(); I != N; ++I) | ||||||||
721 | Result.U.pVal[I] = llvm::byteswap<uint64_t>(U.pVal[N - I - 1]); | ||||||||
722 | if (Result.BitWidth != BitWidth) { | ||||||||
723 | Result.lshrInPlace(Result.BitWidth - BitWidth); | ||||||||
724 | Result.BitWidth = BitWidth; | ||||||||
725 | } | ||||||||
726 | return Result; | ||||||||
727 | } | ||||||||
728 | |||||||||
729 | APInt APInt::reverseBits() const { | ||||||||
730 | switch (BitWidth) { | ||||||||
731 | case 64: | ||||||||
732 | return APInt(BitWidth, llvm::reverseBits<uint64_t>(U.VAL)); | ||||||||
733 | case 32: | ||||||||
734 | return APInt(BitWidth, llvm::reverseBits<uint32_t>(U.VAL)); | ||||||||
735 | case 16: | ||||||||
736 | return APInt(BitWidth, llvm::reverseBits<uint16_t>(U.VAL)); | ||||||||
737 | case 8: | ||||||||
738 | return APInt(BitWidth, llvm::reverseBits<uint8_t>(U.VAL)); | ||||||||
739 | case 0: | ||||||||
740 | return *this; | ||||||||
741 | default: | ||||||||
742 | break; | ||||||||
743 | } | ||||||||
744 | |||||||||
745 | APInt Val(*this); | ||||||||
746 | APInt Reversed(BitWidth, 0); | ||||||||
747 | unsigned S = BitWidth; | ||||||||
748 | |||||||||
749 | for (; Val != 0; Val.lshrInPlace(1)) { | ||||||||
750 | Reversed <<= 1; | ||||||||
751 | Reversed |= Val[0]; | ||||||||
752 | --S; | ||||||||
753 | } | ||||||||
754 | |||||||||
755 | Reversed <<= S; | ||||||||
756 | return Reversed; | ||||||||
757 | } | ||||||||
758 | |||||||||
759 | APInt llvm::APIntOps::GreatestCommonDivisor(APInt A, APInt B) { | ||||||||
760 | // Fast-path a common case. | ||||||||
761 | if (A == B) return A; | ||||||||
762 | |||||||||
763 | // Corner cases: if either operand is zero, the other is the gcd. | ||||||||
764 | if (!A) return B; | ||||||||
765 | if (!B) return A; | ||||||||
766 | |||||||||
767 | // Count common powers of 2 and remove all other powers of 2. | ||||||||
768 | unsigned Pow2; | ||||||||
769 | { | ||||||||
770 | unsigned Pow2_A = A.countr_zero(); | ||||||||
771 | unsigned Pow2_B = B.countr_zero(); | ||||||||
772 | if (Pow2_A > Pow2_B) { | ||||||||
773 | A.lshrInPlace(Pow2_A - Pow2_B); | ||||||||
774 | Pow2 = Pow2_B; | ||||||||
775 | } else if (Pow2_B > Pow2_A) { | ||||||||
776 | B.lshrInPlace(Pow2_B - Pow2_A); | ||||||||
777 | Pow2 = Pow2_A; | ||||||||
778 | } else { | ||||||||
779 | Pow2 = Pow2_A; | ||||||||
780 | } | ||||||||
781 | } | ||||||||
782 | |||||||||
783 | // Both operands are odd multiples of 2^Pow_2: | ||||||||
784 | // | ||||||||
785 | // gcd(a, b) = gcd(|a - b| / 2^i, min(a, b)) | ||||||||
786 | // | ||||||||
787 | // This is a modified version of Stein's algorithm, taking advantage of | ||||||||
788 | // efficient countTrailingZeros(). | ||||||||
789 | while (A != B) { | ||||||||
790 | if (A.ugt(B)) { | ||||||||
791 | A -= B; | ||||||||
792 | A.lshrInPlace(A.countr_zero() - Pow2); | ||||||||
793 | } else { | ||||||||
794 | B -= A; | ||||||||
795 | B.lshrInPlace(B.countr_zero() - Pow2); | ||||||||
796 | } | ||||||||
797 | } | ||||||||
798 | |||||||||
799 | return A; | ||||||||
800 | } | ||||||||
801 | |||||||||
802 | APInt llvm::APIntOps::RoundDoubleToAPInt(double Double, unsigned width) { | ||||||||
803 | uint64_t I = bit_cast<uint64_t>(Double); | ||||||||
804 | |||||||||
805 | // Get the sign bit from the highest order bit | ||||||||
806 | bool isNeg = I >> 63; | ||||||||
807 | |||||||||
808 | // Get the 11-bit exponent and adjust for the 1023 bit bias | ||||||||
809 | int64_t exp = ((I >> 52) & 0x7ff) - 1023; | ||||||||
810 | |||||||||
811 | // If the exponent is negative, the value is < 0 so just return 0. | ||||||||
812 | if (exp < 0) | ||||||||
813 | return APInt(width, 0u); | ||||||||
814 | |||||||||
815 | // Extract the mantissa by clearing the top 12 bits (sign + exponent). | ||||||||
816 | uint64_t mantissa = (I & (~0ULL >> 12)) | 1ULL << 52; | ||||||||
817 | |||||||||
818 | // If the exponent doesn't shift all bits out of the mantissa | ||||||||
819 | if (exp < 52) | ||||||||
820 | return isNeg ? -APInt(width, mantissa >> (52 - exp)) : | ||||||||
821 | APInt(width, mantissa >> (52 - exp)); | ||||||||
822 | |||||||||
823 | // If the client didn't provide enough bits for us to shift the mantissa into | ||||||||
824 | // then the result is undefined, just return 0 | ||||||||
825 | if (width <= exp - 52) | ||||||||
826 | return APInt(width, 0); | ||||||||
827 | |||||||||
828 | // Otherwise, we have to shift the mantissa bits up to the right location | ||||||||
829 | APInt Tmp(width, mantissa); | ||||||||
830 | Tmp <<= (unsigned)exp - 52; | ||||||||
831 | return isNeg ? -Tmp : Tmp; | ||||||||
832 | } | ||||||||
833 | |||||||||
834 | /// This function converts this APInt to a double. | ||||||||
835 | /// The layout for double is as following (IEEE Standard 754): | ||||||||
836 | /// -------------------------------------- | ||||||||
837 | /// | Sign Exponent Fraction Bias | | ||||||||
838 | /// |-------------------------------------- | | ||||||||
839 | /// | 1[63] 11[62-52] 52[51-00] 1023 | | ||||||||
840 | /// -------------------------------------- | ||||||||
841 | double APInt::roundToDouble(bool isSigned) const { | ||||||||
842 | |||||||||
843 | // Handle the simple case where the value is contained in one uint64_t. | ||||||||
844 | // It is wrong to optimize getWord(0) to VAL; there might be more than one word. | ||||||||
845 | if (isSingleWord() || getActiveBits() <= APINT_BITS_PER_WORD) { | ||||||||
846 | if (isSigned) { | ||||||||
847 | int64_t sext = SignExtend64(getWord(0), BitWidth); | ||||||||
848 | return double(sext); | ||||||||
849 | } else | ||||||||
850 | return double(getWord(0)); | ||||||||
851 | } | ||||||||
852 | |||||||||
853 | // Determine if the value is negative. | ||||||||
854 | bool isNeg = isSigned ? (*this)[BitWidth-1] : false; | ||||||||
855 | |||||||||
856 | // Construct the absolute value if we're negative. | ||||||||
857 | APInt Tmp(isNeg ? -(*this) : (*this)); | ||||||||
858 | |||||||||
859 | // Figure out how many bits we're using. | ||||||||
860 | unsigned n = Tmp.getActiveBits(); | ||||||||
861 | |||||||||
862 | // The exponent (without bias normalization) is just the number of bits | ||||||||
863 | // we are using. Note that the sign bit is gone since we constructed the | ||||||||
864 | // absolute value. | ||||||||
865 | uint64_t exp = n; | ||||||||
866 | |||||||||
867 | // Return infinity for exponent overflow | ||||||||
868 | if (exp > 1023) { | ||||||||
869 | if (!isSigned || !isNeg) | ||||||||
870 | return std::numeric_limits<double>::infinity(); | ||||||||
871 | else | ||||||||
872 | return -std::numeric_limits<double>::infinity(); | ||||||||
873 | } | ||||||||
874 | exp += 1023; // Increment for 1023 bias | ||||||||
875 | |||||||||
876 | // Number of bits in mantissa is 52. To obtain the mantissa value, we must | ||||||||
877 | // extract the high 52 bits from the correct words in pVal. | ||||||||
878 | uint64_t mantissa; | ||||||||
879 | unsigned hiWord = whichWord(n-1); | ||||||||
880 | if (hiWord == 0) { | ||||||||
881 | mantissa = Tmp.U.pVal[0]; | ||||||||
882 | if (n > 52) | ||||||||
883 | mantissa >>= n - 52; // shift down, we want the top 52 bits. | ||||||||
884 | } else { | ||||||||
885 | assert(hiWord > 0 && "huh?")(static_cast <bool> (hiWord > 0 && "huh?") ? void (0) : __assert_fail ("hiWord > 0 && \"huh?\"" , "llvm/lib/Support/APInt.cpp", 885, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
886 | uint64_t hibits = Tmp.U.pVal[hiWord] << (52 - n % APINT_BITS_PER_WORD); | ||||||||
887 | uint64_t lobits = Tmp.U.pVal[hiWord-1] >> (11 + n % APINT_BITS_PER_WORD); | ||||||||
888 | mantissa = hibits | lobits; | ||||||||
889 | } | ||||||||
890 | |||||||||
891 | // The leading bit of mantissa is implicit, so get rid of it. | ||||||||
892 | uint64_t sign = isNeg ? (1ULL << (APINT_BITS_PER_WORD - 1)) : 0; | ||||||||
893 | uint64_t I = sign | (exp << 52) | mantissa; | ||||||||
894 | return bit_cast<double>(I); | ||||||||
895 | } | ||||||||
896 | |||||||||
897 | // Truncate to new width. | ||||||||
898 | APInt APInt::trunc(unsigned width) const { | ||||||||
899 | assert(width <= BitWidth && "Invalid APInt Truncate request")(static_cast <bool> (width <= BitWidth && "Invalid APInt Truncate request" ) ? void (0) : __assert_fail ("width <= BitWidth && \"Invalid APInt Truncate request\"" , "llvm/lib/Support/APInt.cpp", 899, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
900 | |||||||||
901 | if (width <= APINT_BITS_PER_WORD) | ||||||||
902 | return APInt(width, getRawData()[0]); | ||||||||
903 | |||||||||
904 | if (width == BitWidth) | ||||||||
905 | return *this; | ||||||||
906 | |||||||||
907 | APInt Result(getMemory(getNumWords(width)), width); | ||||||||
908 | |||||||||
909 | // Copy full words. | ||||||||
910 | unsigned i; | ||||||||
911 | for (i = 0; i != width / APINT_BITS_PER_WORD; i++) | ||||||||
912 | Result.U.pVal[i] = U.pVal[i]; | ||||||||
913 | |||||||||
914 | // Truncate and copy any partial word. | ||||||||
915 | unsigned bits = (0 - width) % APINT_BITS_PER_WORD; | ||||||||
916 | if (bits != 0) | ||||||||
917 | Result.U.pVal[i] = U.pVal[i] << bits >> bits; | ||||||||
918 | |||||||||
919 | return Result; | ||||||||
920 | } | ||||||||
921 | |||||||||
922 | // Truncate to new width with unsigned saturation. | ||||||||
923 | APInt APInt::truncUSat(unsigned width) const { | ||||||||
924 | assert(width <= BitWidth && "Invalid APInt Truncate request")(static_cast <bool> (width <= BitWidth && "Invalid APInt Truncate request" ) ? void (0) : __assert_fail ("width <= BitWidth && \"Invalid APInt Truncate request\"" , "llvm/lib/Support/APInt.cpp", 924, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
925 | |||||||||
926 | // Can we just losslessly truncate it? | ||||||||
927 | if (isIntN(width)) | ||||||||
928 | return trunc(width); | ||||||||
929 | // If not, then just return the new limit. | ||||||||
930 | return APInt::getMaxValue(width); | ||||||||
931 | } | ||||||||
932 | |||||||||
933 | // Truncate to new width with signed saturation. | ||||||||
934 | APInt APInt::truncSSat(unsigned width) const { | ||||||||
935 | assert(width <= BitWidth && "Invalid APInt Truncate request")(static_cast <bool> (width <= BitWidth && "Invalid APInt Truncate request" ) ? void (0) : __assert_fail ("width <= BitWidth && \"Invalid APInt Truncate request\"" , "llvm/lib/Support/APInt.cpp", 935, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
936 | |||||||||
937 | // Can we just losslessly truncate it? | ||||||||
938 | if (isSignedIntN(width)) | ||||||||
939 | return trunc(width); | ||||||||
940 | // If not, then just return the new limits. | ||||||||
941 | return isNegative() ? APInt::getSignedMinValue(width) | ||||||||
942 | : APInt::getSignedMaxValue(width); | ||||||||
943 | } | ||||||||
944 | |||||||||
945 | // Sign extend to a new width. | ||||||||
946 | APInt APInt::sext(unsigned Width) const { | ||||||||
947 | assert(Width >= BitWidth && "Invalid APInt SignExtend request")(static_cast <bool> (Width >= BitWidth && "Invalid APInt SignExtend request" ) ? void (0) : __assert_fail ("Width >= BitWidth && \"Invalid APInt SignExtend request\"" , "llvm/lib/Support/APInt.cpp", 947, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
948 | |||||||||
949 | if (Width <= APINT_BITS_PER_WORD) | ||||||||
950 | return APInt(Width, SignExtend64(U.VAL, BitWidth)); | ||||||||
951 | |||||||||
952 | if (Width == BitWidth) | ||||||||
953 | return *this; | ||||||||
954 | |||||||||
955 | APInt Result(getMemory(getNumWords(Width)), Width); | ||||||||
956 | |||||||||
957 | // Copy words. | ||||||||
958 | std::memcpy(Result.U.pVal, getRawData(), getNumWords() * APINT_WORD_SIZE); | ||||||||
959 | |||||||||
960 | // Sign extend the last word since there may be unused bits in the input. | ||||||||
961 | Result.U.pVal[getNumWords() - 1] = | ||||||||
962 | SignExtend64(Result.U.pVal[getNumWords() - 1], | ||||||||
963 | ((BitWidth - 1) % APINT_BITS_PER_WORD) + 1); | ||||||||
964 | |||||||||
965 | // Fill with sign bits. | ||||||||
966 | std::memset(Result.U.pVal + getNumWords(), isNegative() ? -1 : 0, | ||||||||
967 | (Result.getNumWords() - getNumWords()) * APINT_WORD_SIZE); | ||||||||
968 | Result.clearUnusedBits(); | ||||||||
969 | return Result; | ||||||||
970 | } | ||||||||
971 | |||||||||
972 | // Zero extend to a new width. | ||||||||
973 | APInt APInt::zext(unsigned width) const { | ||||||||
974 | assert(width >= BitWidth && "Invalid APInt ZeroExtend request")(static_cast <bool> (width >= BitWidth && "Invalid APInt ZeroExtend request" ) ? void (0) : __assert_fail ("width >= BitWidth && \"Invalid APInt ZeroExtend request\"" , "llvm/lib/Support/APInt.cpp", 974, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
975 | |||||||||
976 | if (width <= APINT_BITS_PER_WORD) | ||||||||
977 | return APInt(width, U.VAL); | ||||||||
978 | |||||||||
979 | if (width == BitWidth) | ||||||||
980 | return *this; | ||||||||
981 | |||||||||
982 | APInt Result(getMemory(getNumWords(width)), width); | ||||||||
983 | |||||||||
984 | // Copy words. | ||||||||
985 | std::memcpy(Result.U.pVal, getRawData(), getNumWords() * APINT_WORD_SIZE); | ||||||||
986 | |||||||||
987 | // Zero remaining words. | ||||||||
988 | std::memset(Result.U.pVal + getNumWords(), 0, | ||||||||
989 | (Result.getNumWords() - getNumWords()) * APINT_WORD_SIZE); | ||||||||
990 | |||||||||
991 | return Result; | ||||||||
992 | } | ||||||||
993 | |||||||||
994 | APInt APInt::zextOrTrunc(unsigned width) const { | ||||||||
995 | if (BitWidth < width) | ||||||||
996 | return zext(width); | ||||||||
997 | if (BitWidth > width) | ||||||||
998 | return trunc(width); | ||||||||
999 | return *this; | ||||||||
1000 | } | ||||||||
1001 | |||||||||
1002 | APInt APInt::sextOrTrunc(unsigned width) const { | ||||||||
1003 | if (BitWidth < width) | ||||||||
1004 | return sext(width); | ||||||||
1005 | if (BitWidth > width) | ||||||||
1006 | return trunc(width); | ||||||||
1007 | return *this; | ||||||||
1008 | } | ||||||||
1009 | |||||||||
1010 | /// Arithmetic right-shift this APInt by shiftAmt. | ||||||||
1011 | /// Arithmetic right-shift function. | ||||||||
1012 | void APInt::ashrInPlace(const APInt &shiftAmt) { | ||||||||
1013 | ashrInPlace((unsigned)shiftAmt.getLimitedValue(BitWidth)); | ||||||||
1014 | } | ||||||||
1015 | |||||||||
1016 | /// Arithmetic right-shift this APInt by shiftAmt. | ||||||||
1017 | /// Arithmetic right-shift function. | ||||||||
1018 | void APInt::ashrSlowCase(unsigned ShiftAmt) { | ||||||||
1019 | // Don't bother performing a no-op shift. | ||||||||
1020 | if (!ShiftAmt) | ||||||||
1021 | return; | ||||||||
1022 | |||||||||
1023 | // Save the original sign bit for later. | ||||||||
1024 | bool Negative = isNegative(); | ||||||||
1025 | |||||||||
1026 | // WordShift is the inter-part shift; BitShift is intra-part shift. | ||||||||
1027 | unsigned WordShift = ShiftAmt / APINT_BITS_PER_WORD; | ||||||||
1028 | unsigned BitShift = ShiftAmt % APINT_BITS_PER_WORD; | ||||||||
1029 | |||||||||
1030 | unsigned WordsToMove = getNumWords() - WordShift; | ||||||||
1031 | if (WordsToMove != 0) { | ||||||||
1032 | // Sign extend the last word to fill in the unused bits. | ||||||||
1033 | U.pVal[getNumWords() - 1] = SignExtend64( | ||||||||
1034 | U.pVal[getNumWords() - 1], ((BitWidth - 1) % APINT_BITS_PER_WORD) + 1); | ||||||||
1035 | |||||||||
1036 | // Fastpath for moving by whole words. | ||||||||
1037 | if (BitShift == 0) { | ||||||||
1038 | std::memmove(U.pVal, U.pVal + WordShift, WordsToMove * APINT_WORD_SIZE); | ||||||||
1039 | } else { | ||||||||
1040 | // Move the words containing significant bits. | ||||||||
1041 | for (unsigned i = 0; i != WordsToMove - 1; ++i) | ||||||||
1042 | U.pVal[i] = (U.pVal[i + WordShift] >> BitShift) | | ||||||||
1043 | (U.pVal[i + WordShift + 1] << (APINT_BITS_PER_WORD - BitShift)); | ||||||||
1044 | |||||||||
1045 | // Handle the last word which has no high bits to copy. | ||||||||
1046 | U.pVal[WordsToMove - 1] = U.pVal[WordShift + WordsToMove - 1] >> BitShift; | ||||||||
1047 | // Sign extend one more time. | ||||||||
1048 | U.pVal[WordsToMove - 1] = | ||||||||
1049 | SignExtend64(U.pVal[WordsToMove - 1], APINT_BITS_PER_WORD - BitShift); | ||||||||
1050 | } | ||||||||
1051 | } | ||||||||
1052 | |||||||||
1053 | // Fill in the remainder based on the original sign. | ||||||||
1054 | std::memset(U.pVal + WordsToMove, Negative ? -1 : 0, | ||||||||
1055 | WordShift * APINT_WORD_SIZE); | ||||||||
1056 | clearUnusedBits(); | ||||||||
1057 | } | ||||||||
1058 | |||||||||
1059 | /// Logical right-shift this APInt by shiftAmt. | ||||||||
1060 | /// Logical right-shift function. | ||||||||
1061 | void APInt::lshrInPlace(const APInt &shiftAmt) { | ||||||||
1062 | lshrInPlace((unsigned)shiftAmt.getLimitedValue(BitWidth)); | ||||||||
1063 | } | ||||||||
1064 | |||||||||
1065 | /// Logical right-shift this APInt by shiftAmt. | ||||||||
1066 | /// Logical right-shift function. | ||||||||
1067 | void APInt::lshrSlowCase(unsigned ShiftAmt) { | ||||||||
1068 | tcShiftRight(U.pVal, getNumWords(), ShiftAmt); | ||||||||
1069 | } | ||||||||
1070 | |||||||||
1071 | /// Left-shift this APInt by shiftAmt. | ||||||||
1072 | /// Left-shift function. | ||||||||
1073 | APInt &APInt::operator<<=(const APInt &shiftAmt) { | ||||||||
1074 | // It's undefined behavior in C to shift by BitWidth or greater. | ||||||||
1075 | *this <<= (unsigned)shiftAmt.getLimitedValue(BitWidth); | ||||||||
1076 | return *this; | ||||||||
1077 | } | ||||||||
1078 | |||||||||
1079 | void APInt::shlSlowCase(unsigned ShiftAmt) { | ||||||||
1080 | tcShiftLeft(U.pVal, getNumWords(), ShiftAmt); | ||||||||
1081 | clearUnusedBits(); | ||||||||
1082 | } | ||||||||
1083 | |||||||||
1084 | // Calculate the rotate amount modulo the bit width. | ||||||||
1085 | static unsigned rotateModulo(unsigned BitWidth, const APInt &rotateAmt) { | ||||||||
1086 | if (LLVM_UNLIKELY(BitWidth == 0)__builtin_expect((bool)(BitWidth == 0), false)) | ||||||||
1087 | return 0; | ||||||||
1088 | unsigned rotBitWidth = rotateAmt.getBitWidth(); | ||||||||
1089 | APInt rot = rotateAmt; | ||||||||
1090 | if (rotBitWidth < BitWidth) { | ||||||||
1091 | // Extend the rotate APInt, so that the urem doesn't divide by 0. | ||||||||
1092 | // e.g. APInt(1, 32) would give APInt(1, 0). | ||||||||
1093 | rot = rotateAmt.zext(BitWidth); | ||||||||
1094 | } | ||||||||
1095 | rot = rot.urem(APInt(rot.getBitWidth(), BitWidth)); | ||||||||
1096 | return rot.getLimitedValue(BitWidth); | ||||||||
1097 | } | ||||||||
1098 | |||||||||
1099 | APInt APInt::rotl(const APInt &rotateAmt) const { | ||||||||
1100 | return rotl(rotateModulo(BitWidth, rotateAmt)); | ||||||||
1101 | } | ||||||||
1102 | |||||||||
1103 | APInt APInt::rotl(unsigned rotateAmt) const { | ||||||||
1104 | if (LLVM_UNLIKELY(BitWidth == 0)__builtin_expect((bool)(BitWidth == 0), false)) | ||||||||
1105 | return *this; | ||||||||
1106 | rotateAmt %= BitWidth; | ||||||||
1107 | if (rotateAmt == 0) | ||||||||
1108 | return *this; | ||||||||
1109 | return shl(rotateAmt) | lshr(BitWidth - rotateAmt); | ||||||||
1110 | } | ||||||||
1111 | |||||||||
1112 | APInt APInt::rotr(const APInt &rotateAmt) const { | ||||||||
1113 | return rotr(rotateModulo(BitWidth, rotateAmt)); | ||||||||
1114 | } | ||||||||
1115 | |||||||||
1116 | APInt APInt::rotr(unsigned rotateAmt) const { | ||||||||
1117 | if (BitWidth == 0) | ||||||||
1118 | return *this; | ||||||||
1119 | rotateAmt %= BitWidth; | ||||||||
1120 | if (rotateAmt == 0) | ||||||||
1121 | return *this; | ||||||||
1122 | return lshr(rotateAmt) | shl(BitWidth - rotateAmt); | ||||||||
1123 | } | ||||||||
1124 | |||||||||
1125 | /// \returns the nearest log base 2 of this APInt. Ties round up. | ||||||||
1126 | /// | ||||||||
1127 | /// NOTE: When we have a BitWidth of 1, we define: | ||||||||
1128 | /// | ||||||||
1129 | /// log2(0) = UINT32_MAX | ||||||||
1130 | /// log2(1) = 0 | ||||||||
1131 | /// | ||||||||
1132 | /// to get around any mathematical concerns resulting from | ||||||||
1133 | /// referencing 2 in a space where 2 does no exist. | ||||||||
1134 | unsigned APInt::nearestLogBase2() const { | ||||||||
1135 | // Special case when we have a bitwidth of 1. If VAL is 1, then we | ||||||||
1136 | // get 0. If VAL is 0, we get WORDTYPE_MAX which gets truncated to | ||||||||
1137 | // UINT32_MAX. | ||||||||
1138 | if (BitWidth == 1) | ||||||||
1139 | return U.VAL - 1; | ||||||||
1140 | |||||||||
1141 | // Handle the zero case. | ||||||||
1142 | if (isZero()) | ||||||||
1143 | return UINT32_MAX(4294967295U); | ||||||||
1144 | |||||||||
1145 | // The non-zero case is handled by computing: | ||||||||
1146 | // | ||||||||
1147 | // nearestLogBase2(x) = logBase2(x) + x[logBase2(x)-1]. | ||||||||
1148 | // | ||||||||
1149 | // where x[i] is referring to the value of the ith bit of x. | ||||||||
1150 | unsigned lg = logBase2(); | ||||||||
1151 | return lg + unsigned((*this)[lg - 1]); | ||||||||
1152 | } | ||||||||
1153 | |||||||||
1154 | // Square Root - this method computes and returns the square root of "this". | ||||||||
1155 | // Three mechanisms are used for computation. For small values (<= 5 bits), | ||||||||
1156 | // a table lookup is done. This gets some performance for common cases. For | ||||||||
1157 | // values using less than 52 bits, the value is converted to double and then | ||||||||
1158 | // the libc sqrt function is called. The result is rounded and then converted | ||||||||
1159 | // back to a uint64_t which is then used to construct the result. Finally, | ||||||||
1160 | // the Babylonian method for computing square roots is used. | ||||||||
1161 | APInt APInt::sqrt() const { | ||||||||
1162 | |||||||||
1163 | // Determine the magnitude of the value. | ||||||||
1164 | unsigned magnitude = getActiveBits(); | ||||||||
1165 | |||||||||
1166 | // Use a fast table for some small values. This also gets rid of some | ||||||||
1167 | // rounding errors in libc sqrt for small values. | ||||||||
1168 | if (magnitude <= 5) { | ||||||||
1169 | static const uint8_t results[32] = { | ||||||||
1170 | /* 0 */ 0, | ||||||||
1171 | /* 1- 2 */ 1, 1, | ||||||||
1172 | /* 3- 6 */ 2, 2, 2, 2, | ||||||||
1173 | /* 7-12 */ 3, 3, 3, 3, 3, 3, | ||||||||
1174 | /* 13-20 */ 4, 4, 4, 4, 4, 4, 4, 4, | ||||||||
1175 | /* 21-30 */ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, | ||||||||
1176 | /* 31 */ 6 | ||||||||
1177 | }; | ||||||||
1178 | return APInt(BitWidth, results[ (isSingleWord() ? U.VAL : U.pVal[0]) ]); | ||||||||
1179 | } | ||||||||
1180 | |||||||||
1181 | // If the magnitude of the value fits in less than 52 bits (the precision of | ||||||||
1182 | // an IEEE double precision floating point value), then we can use the | ||||||||
1183 | // libc sqrt function which will probably use a hardware sqrt computation. | ||||||||
1184 | // This should be faster than the algorithm below. | ||||||||
1185 | if (magnitude < 52) { | ||||||||
1186 | return APInt(BitWidth, | ||||||||
1187 | uint64_t(::round(::sqrt(double(isSingleWord() ? U.VAL | ||||||||
1188 | : U.pVal[0]))))); | ||||||||
1189 | } | ||||||||
1190 | |||||||||
1191 | // Okay, all the short cuts are exhausted. We must compute it. The following | ||||||||
1192 | // is a classical Babylonian method for computing the square root. This code | ||||||||
1193 | // was adapted to APInt from a wikipedia article on such computations. | ||||||||
1194 | // See http://www.wikipedia.org/ and go to the page named | ||||||||
1195 | // Calculate_an_integer_square_root. | ||||||||
1196 | unsigned nbits = BitWidth, i = 4; | ||||||||
1197 | APInt testy(BitWidth, 16); | ||||||||
1198 | APInt x_old(BitWidth, 1); | ||||||||
1199 | APInt x_new(BitWidth, 0); | ||||||||
1200 | APInt two(BitWidth, 2); | ||||||||
1201 | |||||||||
1202 | // Select a good starting value using binary logarithms. | ||||||||
1203 | for (;; i += 2, testy = testy.shl(2)) | ||||||||
1204 | if (i >= nbits || this->ule(testy)) { | ||||||||
1205 | x_old = x_old.shl(i / 2); | ||||||||
1206 | break; | ||||||||
1207 | } | ||||||||
1208 | |||||||||
1209 | // Use the Babylonian method to arrive at the integer square root: | ||||||||
1210 | for (;;) { | ||||||||
1211 | x_new = (this->udiv(x_old) + x_old).udiv(two); | ||||||||
1212 | if (x_old.ule(x_new)) | ||||||||
1213 | break; | ||||||||
1214 | x_old = x_new; | ||||||||
1215 | } | ||||||||
1216 | |||||||||
1217 | // Make sure we return the closest approximation | ||||||||
1218 | // NOTE: The rounding calculation below is correct. It will produce an | ||||||||
1219 | // off-by-one discrepancy with results from pari/gp. That discrepancy has been | ||||||||
1220 | // determined to be a rounding issue with pari/gp as it begins to use a | ||||||||
1221 | // floating point representation after 192 bits. There are no discrepancies | ||||||||
1222 | // between this algorithm and pari/gp for bit widths < 192 bits. | ||||||||
1223 | APInt square(x_old * x_old); | ||||||||
1224 | APInt nextSquare((x_old + 1) * (x_old +1)); | ||||||||
1225 | if (this->ult(square)) | ||||||||
1226 | return x_old; | ||||||||
1227 | assert(this->ule(nextSquare) && "Error in APInt::sqrt computation")(static_cast <bool> (this->ule(nextSquare) && "Error in APInt::sqrt computation") ? void (0) : __assert_fail ("this->ule(nextSquare) && \"Error in APInt::sqrt computation\"" , "llvm/lib/Support/APInt.cpp", 1227, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1228 | APInt midpoint((nextSquare - square).udiv(two)); | ||||||||
1229 | APInt offset(*this - square); | ||||||||
1230 | if (offset.ult(midpoint)) | ||||||||
1231 | return x_old; | ||||||||
1232 | return x_old + 1; | ||||||||
1233 | } | ||||||||
1234 | |||||||||
1235 | /// Computes the multiplicative inverse of this APInt for a given modulo. The | ||||||||
1236 | /// iterative extended Euclidean algorithm is used to solve for this value, | ||||||||
1237 | /// however we simplify it to speed up calculating only the inverse, and take | ||||||||
1238 | /// advantage of div+rem calculations. We also use some tricks to avoid copying | ||||||||
1239 | /// (potentially large) APInts around. | ||||||||
1240 | /// WARNING: a value of '0' may be returned, | ||||||||
1241 | /// signifying that no multiplicative inverse exists! | ||||||||
1242 | APInt APInt::multiplicativeInverse(const APInt& modulo) const { | ||||||||
1243 | assert(ult(modulo) && "This APInt must be smaller than the modulo")(static_cast <bool> (ult(modulo) && "This APInt must be smaller than the modulo" ) ? void (0) : __assert_fail ("ult(modulo) && \"This APInt must be smaller than the modulo\"" , "llvm/lib/Support/APInt.cpp", 1243, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1244 | |||||||||
1245 | // Using the properties listed at the following web page (accessed 06/21/08): | ||||||||
1246 | // http://www.numbertheory.org/php/euclid.html | ||||||||
1247 | // (especially the properties numbered 3, 4 and 9) it can be proved that | ||||||||
1248 | // BitWidth bits suffice for all the computations in the algorithm implemented | ||||||||
1249 | // below. More precisely, this number of bits suffice if the multiplicative | ||||||||
1250 | // inverse exists, but may not suffice for the general extended Euclidean | ||||||||
1251 | // algorithm. | ||||||||
1252 | |||||||||
1253 | APInt r[2] = { modulo, *this }; | ||||||||
1254 | APInt t[2] = { APInt(BitWidth, 0), APInt(BitWidth, 1) }; | ||||||||
1255 | APInt q(BitWidth, 0); | ||||||||
1256 | |||||||||
1257 | unsigned i; | ||||||||
1258 | for (i = 0; r[i^1] != 0; i ^= 1) { | ||||||||
1259 | // An overview of the math without the confusing bit-flipping: | ||||||||
1260 | // q = r[i-2] / r[i-1] | ||||||||
1261 | // r[i] = r[i-2] % r[i-1] | ||||||||
1262 | // t[i] = t[i-2] - t[i-1] * q | ||||||||
1263 | udivrem(r[i], r[i^1], q, r[i]); | ||||||||
1264 | t[i] -= t[i^1] * q; | ||||||||
1265 | } | ||||||||
1266 | |||||||||
1267 | // If this APInt and the modulo are not coprime, there is no multiplicative | ||||||||
1268 | // inverse, so return 0. We check this by looking at the next-to-last | ||||||||
1269 | // remainder, which is the gcd(*this,modulo) as calculated by the Euclidean | ||||||||
1270 | // algorithm. | ||||||||
1271 | if (r[i] != 1) | ||||||||
1272 | return APInt(BitWidth, 0); | ||||||||
1273 | |||||||||
1274 | // The next-to-last t is the multiplicative inverse. However, we are | ||||||||
1275 | // interested in a positive inverse. Calculate a positive one from a negative | ||||||||
1276 | // one if necessary. A simple addition of the modulo suffices because | ||||||||
1277 | // abs(t[i]) is known to be less than *this/2 (see the link above). | ||||||||
1278 | if (t[i].isNegative()) | ||||||||
1279 | t[i] += modulo; | ||||||||
1280 | |||||||||
1281 | return std::move(t[i]); | ||||||||
1282 | } | ||||||||
1283 | |||||||||
1284 | /// Implementation of Knuth's Algorithm D (Division of nonnegative integers) | ||||||||
1285 | /// from "Art of Computer Programming, Volume 2", section 4.3.1, p. 272. The | ||||||||
1286 | /// variables here have the same names as in the algorithm. Comments explain | ||||||||
1287 | /// the algorithm and any deviation from it. | ||||||||
1288 | static void KnuthDiv(uint32_t *u, uint32_t *v, uint32_t *q, uint32_t* r, | ||||||||
1289 | unsigned m, unsigned n) { | ||||||||
1290 | assert(u && "Must provide dividend")(static_cast <bool> (u && "Must provide dividend" ) ? void (0) : __assert_fail ("u && \"Must provide dividend\"" , "llvm/lib/Support/APInt.cpp", 1290, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
| |||||||||
1291 | assert(v && "Must provide divisor")(static_cast <bool> (v && "Must provide divisor" ) ? void (0) : __assert_fail ("v && \"Must provide divisor\"" , "llvm/lib/Support/APInt.cpp", 1291, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1292 | assert(q && "Must provide quotient")(static_cast <bool> (q && "Must provide quotient" ) ? void (0) : __assert_fail ("q && \"Must provide quotient\"" , "llvm/lib/Support/APInt.cpp", 1292, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1293 | assert(u != v && u != q && v != q && "Must use different memory")(static_cast <bool> (u != v && u != q && v != q && "Must use different memory") ? void (0) : __assert_fail ("u != v && u != q && v != q && \"Must use different memory\"" , "llvm/lib/Support/APInt.cpp", 1293, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1294 | assert(n>1 && "n must be > 1")(static_cast <bool> (n>1 && "n must be > 1" ) ? void (0) : __assert_fail ("n>1 && \"n must be > 1\"" , "llvm/lib/Support/APInt.cpp", 1294, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1295 | |||||||||
1296 | // b denotes the base of the number system. In our case b is 2^32. | ||||||||
1297 | const uint64_t b = uint64_t(1) << 32; | ||||||||
1298 | |||||||||
1299 | // The DEBUG macros here tend to be spam in the debug output if you're not | ||||||||
1300 | // debugging this code. Disable them unless KNUTH_DEBUG is defined. | ||||||||
1301 | #ifdef KNUTH_DEBUG | ||||||||
1302 | #define DEBUG_KNUTH(X)do {} while(false) LLVM_DEBUG(X)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { X; } } while (false) | ||||||||
1303 | #else | ||||||||
1304 | #define DEBUG_KNUTH(X)do {} while(false) do {} while(false) | ||||||||
1305 | #endif | ||||||||
1306 | |||||||||
1307 | DEBUG_KNUTH(dbgs() << "KnuthDiv: m=" << m << " n=" << n << '\n')do {} while(false); | ||||||||
1308 | DEBUG_KNUTH(dbgs() << "KnuthDiv: original:")do {} while(false); | ||||||||
1309 | DEBUG_KNUTH(for (int i = m + n; i >= 0; i--) dbgs() << " " << u[i])do {} while(false); | ||||||||
1310 | DEBUG_KNUTH(dbgs() << " by")do {} while(false); | ||||||||
1311 | DEBUG_KNUTH(for (int i = n; i > 0; i--) dbgs() << " " << v[i - 1])do {} while(false); | ||||||||
1312 | DEBUG_KNUTH(dbgs() << '\n')do {} while(false); | ||||||||
1313 | // D1. [Normalize.] Set d = b / (v[n-1] + 1) and multiply all the digits of | ||||||||
1314 | // u and v by d. Note that we have taken Knuth's advice here to use a power | ||||||||
1315 | // of 2 value for d such that d * v[n-1] >= b/2 (b is the base). A power of | ||||||||
1316 | // 2 allows us to shift instead of multiply and it is easy to determine the | ||||||||
1317 | // shift amount from the leading zeros. We are basically normalizing the u | ||||||||
1318 | // and v so that its high bits are shifted to the top of v's range without | ||||||||
1319 | // overflow. Note that this can require an extra word in u so that u must | ||||||||
1320 | // be of length m+n+1. | ||||||||
1321 | unsigned shift = llvm::countl_zero(v[n - 1]); | ||||||||
1322 | uint32_t v_carry = 0; | ||||||||
1323 | uint32_t u_carry = 0; | ||||||||
1324 | if (shift
| ||||||||
1325 | for (unsigned i = 0; i < m+n; ++i) { | ||||||||
1326 | uint32_t u_tmp = u[i] >> (32 - shift); | ||||||||
1327 | u[i] = (u[i] << shift) | u_carry; | ||||||||
1328 | u_carry = u_tmp; | ||||||||
1329 | } | ||||||||
1330 | for (unsigned i = 0; i
| ||||||||
1331 | uint32_t v_tmp = v[i] >> (32 - shift); | ||||||||
1332 | v[i] = (v[i] << shift) | v_carry; | ||||||||
1333 | v_carry = v_tmp; | ||||||||
1334 | } | ||||||||
1335 | } | ||||||||
1336 | u[m+n] = u_carry; | ||||||||
1337 | |||||||||
1338 | DEBUG_KNUTH(dbgs() << "KnuthDiv: normal:")do {} while(false); | ||||||||
1339 | DEBUG_KNUTH(for (int i = m + n; i >= 0; i--) dbgs() << " " << u[i])do {} while(false); | ||||||||
1340 | DEBUG_KNUTH(dbgs() << " by")do {} while(false); | ||||||||
1341 | DEBUG_KNUTH(for (int i = n; i > 0; i--) dbgs() << " " << v[i - 1])do {} while(false); | ||||||||
1342 | DEBUG_KNUTH(dbgs() << '\n')do {} while(false); | ||||||||
1343 | |||||||||
1344 | // D2. [Initialize j.] Set j to m. This is the loop counter over the places. | ||||||||
1345 | int j = m; | ||||||||
1346 | do { | ||||||||
1347 | DEBUG_KNUTH(dbgs() << "KnuthDiv: quotient digit #" << j << '\n')do {} while(false); | ||||||||
1348 | // D3. [Calculate q'.]. | ||||||||
1349 | // Set qp = (u[j+n]*b + u[j+n-1]) / v[n-1]. (qp=qprime=q') | ||||||||
1350 | // Set rp = (u[j+n]*b + u[j+n-1]) % v[n-1]. (rp=rprime=r') | ||||||||
1351 | // Now test if qp == b or qp*v[n-2] > b*rp + u[j+n-2]; if so, decrease | ||||||||
1352 | // qp by 1, increase rp by v[n-1], and repeat this test if rp < b. The test | ||||||||
1353 | // on v[n-2] determines at high speed most of the cases in which the trial | ||||||||
1354 | // value qp is one too large, and it eliminates all cases where qp is two | ||||||||
1355 | // too large. | ||||||||
1356 | uint64_t dividend = Make_64(u[j+n], u[j+n-1]); | ||||||||
1357 | DEBUG_KNUTH(dbgs() << "KnuthDiv: dividend == " << dividend << '\n')do {} while(false); | ||||||||
1358 | uint64_t qp = dividend / v[n-1]; | ||||||||
1359 | uint64_t rp = dividend % v[n-1]; | ||||||||
1360 | if (qp == b || qp*v[n-2] > b*rp + u[j+n-2]) { | ||||||||
1361 | qp--; | ||||||||
1362 | rp += v[n-1]; | ||||||||
1363 | if (rp < b && (qp == b || qp*v[n-2] > b*rp + u[j+n-2])) | ||||||||
1364 | qp--; | ||||||||
1365 | } | ||||||||
1366 | DEBUG_KNUTH(dbgs() << "KnuthDiv: qp == " << qp << ", rp == " << rp << '\n')do {} while(false); | ||||||||
1367 | |||||||||
1368 | // D4. [Multiply and subtract.] Replace (u[j+n]u[j+n-1]...u[j]) with | ||||||||
1369 | // (u[j+n]u[j+n-1]..u[j]) - qp * (v[n-1]...v[1]v[0]). This computation | ||||||||
1370 | // consists of a simple multiplication by a one-place number, combined with | ||||||||
1371 | // a subtraction. | ||||||||
1372 | // The digits (u[j+n]...u[j]) should be kept positive; if the result of | ||||||||
1373 | // this step is actually negative, (u[j+n]...u[j]) should be left as the | ||||||||
1374 | // true value plus b**(n+1), namely as the b's complement of | ||||||||
1375 | // the true value, and a "borrow" to the left should be remembered. | ||||||||
1376 | int64_t borrow = 0; | ||||||||
1377 | for (unsigned i = 0; i < n; ++i) { | ||||||||
1378 | uint64_t p = uint64_t(qp) * uint64_t(v[i]); | ||||||||
1379 | int64_t subres = int64_t(u[j+i]) - borrow - Lo_32(p); | ||||||||
1380 | u[j+i] = Lo_32(subres); | ||||||||
1381 | borrow = Hi_32(p) - Hi_32(subres); | ||||||||
1382 | DEBUG_KNUTH(dbgs() << "KnuthDiv: u[j+i] = " << u[j + i]do {} while(false) | ||||||||
1383 | << ", borrow = " << borrow << '\n')do {} while(false); | ||||||||
1384 | } | ||||||||
1385 | bool isNeg = u[j+n] < borrow; | ||||||||
1386 | u[j+n] -= Lo_32(borrow); | ||||||||
1387 | |||||||||
1388 | DEBUG_KNUTH(dbgs() << "KnuthDiv: after subtraction:")do {} while(false); | ||||||||
1389 | DEBUG_KNUTH(for (int i = m + n; i >= 0; i--) dbgs() << " " << u[i])do {} while(false); | ||||||||
1390 | DEBUG_KNUTH(dbgs() << '\n')do {} while(false); | ||||||||
1391 | |||||||||
1392 | // D5. [Test remainder.] Set q[j] = qp. If the result of step D4 was | ||||||||
1393 | // negative, go to step D6; otherwise go on to step D7. | ||||||||
1394 | q[j] = Lo_32(qp); | ||||||||
1395 | if (isNeg
| ||||||||
1396 | // D6. [Add back]. The probability that this step is necessary is very | ||||||||
1397 | // small, on the order of only 2/b. Make sure that test data accounts for | ||||||||
1398 | // this possibility. Decrease q[j] by 1 | ||||||||
1399 | q[j]--; | ||||||||
1400 | // and add (0v[n-1]...v[1]v[0]) to (u[j+n]u[j+n-1]...u[j+1]u[j]). | ||||||||
1401 | // A carry will occur to the left of u[j+n], and it should be ignored | ||||||||
1402 | // since it cancels with the borrow that occurred in D4. | ||||||||
1403 | bool carry = false; | ||||||||
1404 | for (unsigned i = 0; i < n; i++) { | ||||||||
1405 | uint32_t limit = std::min(u[j+i],v[i]); | ||||||||
1406 | u[j+i] += v[i] + carry; | ||||||||
1407 | carry = u[j+i] < limit || (carry && u[j+i] == limit); | ||||||||
1408 | } | ||||||||
1409 | u[j+n] += carry; | ||||||||
1410 | } | ||||||||
1411 | DEBUG_KNUTH(dbgs() << "KnuthDiv: after correction:")do {} while(false); | ||||||||
1412 | DEBUG_KNUTH(for (int i = m + n; i >= 0; i--) dbgs() << " " << u[i])do {} while(false); | ||||||||
1413 | DEBUG_KNUTH(dbgs() << "\nKnuthDiv: digit result = " << q[j] << '\n')do {} while(false); | ||||||||
1414 | |||||||||
1415 | // D7. [Loop on j.] Decrease j by one. Now if j >= 0, go back to D3. | ||||||||
1416 | } while (--j >= 0); | ||||||||
1417 | |||||||||
1418 | DEBUG_KNUTH(dbgs() << "KnuthDiv: quotient:")do {} while(false); | ||||||||
1419 | DEBUG_KNUTH(for (int i = m; i >= 0; i--) dbgs() << " " << q[i])do {} while(false); | ||||||||
1420 | DEBUG_KNUTH(dbgs() << '\n')do {} while(false); | ||||||||
1421 | |||||||||
1422 | // D8. [Unnormalize]. Now q[...] is the desired quotient, and the desired | ||||||||
1423 | // remainder may be obtained by dividing u[...] by d. If r is non-null we | ||||||||
1424 | // compute the remainder (urem uses this). | ||||||||
1425 | if (r) { | ||||||||
1426 | // The value d is expressed by the "shift" value above since we avoided | ||||||||
1427 | // multiplication by d by using a shift left. So, all we have to do is | ||||||||
1428 | // shift right here. | ||||||||
1429 | if (shift
| ||||||||
1430 | uint32_t carry = 0; | ||||||||
1431 | DEBUG_KNUTH(dbgs() << "KnuthDiv: remainder:")do {} while(false); | ||||||||
1432 | for (int i = n-1; i >= 0; i--) { | ||||||||
1433 | r[i] = (u[i] >> shift) | carry; | ||||||||
| |||||||||
1434 | carry = u[i] << (32 - shift); | ||||||||
1435 | DEBUG_KNUTH(dbgs() << " " << r[i])do {} while(false); | ||||||||
1436 | } | ||||||||
1437 | } else { | ||||||||
1438 | for (int i = n-1; i >= 0; i--) { | ||||||||
1439 | r[i] = u[i]; | ||||||||
1440 | DEBUG_KNUTH(dbgs() << " " << r[i])do {} while(false); | ||||||||
1441 | } | ||||||||
1442 | } | ||||||||
1443 | DEBUG_KNUTH(dbgs() << '\n')do {} while(false); | ||||||||
1444 | } | ||||||||
1445 | DEBUG_KNUTH(dbgs() << '\n')do {} while(false); | ||||||||
1446 | } | ||||||||
1447 | |||||||||
1448 | void APInt::divide(const WordType *LHS, unsigned lhsWords, const WordType *RHS, | ||||||||
1449 | unsigned rhsWords, WordType *Quotient, WordType *Remainder) { | ||||||||
1450 | assert(lhsWords >= rhsWords && "Fractional result")(static_cast <bool> (lhsWords >= rhsWords && "Fractional result") ? void (0) : __assert_fail ("lhsWords >= rhsWords && \"Fractional result\"" , "llvm/lib/Support/APInt.cpp", 1450, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1451 | |||||||||
1452 | // First, compose the values into an array of 32-bit words instead of | ||||||||
1453 | // 64-bit words. This is a necessity of both the "short division" algorithm | ||||||||
1454 | // and the Knuth "classical algorithm" which requires there to be native | ||||||||
1455 | // operations for +, -, and * on an m bit value with an m*2 bit result. We | ||||||||
1456 | // can't use 64-bit operands here because we don't have native results of | ||||||||
1457 | // 128-bits. Furthermore, casting the 64-bit values to 32-bit values won't | ||||||||
1458 | // work on large-endian machines. | ||||||||
1459 | unsigned n = rhsWords * 2; | ||||||||
1460 | unsigned m = (lhsWords * 2) - n; | ||||||||
1461 | |||||||||
1462 | // Allocate space for the temporary values we need either on the stack, if | ||||||||
1463 | // it will fit, or on the heap if it won't. | ||||||||
1464 | uint32_t SPACE[128]; | ||||||||
1465 | uint32_t *U = nullptr; | ||||||||
1466 | uint32_t *V = nullptr; | ||||||||
1467 | uint32_t *Q = nullptr; | ||||||||
1468 | uint32_t *R = nullptr; | ||||||||
1469 | if ((Remainder?4:3)*n+2*m+1 <= 128) { | ||||||||
1470 | U = &SPACE[0]; | ||||||||
1471 | V = &SPACE[m+n+1]; | ||||||||
1472 | Q = &SPACE[(m+n+1) + n]; | ||||||||
1473 | if (Remainder) | ||||||||
1474 | R = &SPACE[(m+n+1) + n + (m+n)]; | ||||||||
1475 | } else { | ||||||||
1476 | U = new uint32_t[m + n + 1]; | ||||||||
1477 | V = new uint32_t[n]; | ||||||||
1478 | Q = new uint32_t[m+n]; | ||||||||
1479 | if (Remainder) | ||||||||
1480 | R = new uint32_t[n]; | ||||||||
1481 | } | ||||||||
1482 | |||||||||
1483 | // Initialize the dividend | ||||||||
1484 | memset(U, 0, (m+n+1)*sizeof(uint32_t)); | ||||||||
1485 | for (unsigned i = 0; i < lhsWords; ++i) { | ||||||||
1486 | uint64_t tmp = LHS[i]; | ||||||||
1487 | U[i * 2] = Lo_32(tmp); | ||||||||
1488 | U[i * 2 + 1] = Hi_32(tmp); | ||||||||
1489 | } | ||||||||
1490 | U[m+n] = 0; // this extra word is for "spill" in the Knuth algorithm. | ||||||||
1491 | |||||||||
1492 | // Initialize the divisor | ||||||||
1493 | memset(V, 0, (n)*sizeof(uint32_t)); | ||||||||
1494 | for (unsigned i = 0; i < rhsWords; ++i) { | ||||||||
1495 | uint64_t tmp = RHS[i]; | ||||||||
1496 | V[i * 2] = Lo_32(tmp); | ||||||||
1497 | V[i * 2 + 1] = Hi_32(tmp); | ||||||||
1498 | } | ||||||||
1499 | |||||||||
1500 | // initialize the quotient and remainder | ||||||||
1501 | memset(Q, 0, (m+n) * sizeof(uint32_t)); | ||||||||
1502 | if (Remainder) | ||||||||
1503 | memset(R, 0, n * sizeof(uint32_t)); | ||||||||
1504 | |||||||||
1505 | // Now, adjust m and n for the Knuth division. n is the number of words in | ||||||||
1506 | // the divisor. m is the number of words by which the dividend exceeds the | ||||||||
1507 | // divisor (i.e. m+n is the length of the dividend). These sizes must not | ||||||||
1508 | // contain any zero words or the Knuth algorithm fails. | ||||||||
1509 | for (unsigned i = n; i > 0 && V[i-1] == 0; i--) { | ||||||||
1510 | n--; | ||||||||
1511 | m++; | ||||||||
1512 | } | ||||||||
1513 | for (unsigned i = m+n; i > 0 && U[i-1] == 0; i--) | ||||||||
1514 | m--; | ||||||||
1515 | |||||||||
1516 | // If we're left with only a single word for the divisor, Knuth doesn't work | ||||||||
1517 | // so we implement the short division algorithm here. This is much simpler | ||||||||
1518 | // and faster because we are certain that we can divide a 64-bit quantity | ||||||||
1519 | // by a 32-bit quantity at hardware speed and short division is simply a | ||||||||
1520 | // series of such operations. This is just like doing short division but we | ||||||||
1521 | // are using base 2^32 instead of base 10. | ||||||||
1522 | assert(n != 0 && "Divide by zero?")(static_cast <bool> (n != 0 && "Divide by zero?" ) ? void (0) : __assert_fail ("n != 0 && \"Divide by zero?\"" , "llvm/lib/Support/APInt.cpp", 1522, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1523 | if (n == 1) { | ||||||||
1524 | uint32_t divisor = V[0]; | ||||||||
1525 | uint32_t remainder = 0; | ||||||||
1526 | for (int i = m; i >= 0; i--) { | ||||||||
1527 | uint64_t partial_dividend = Make_64(remainder, U[i]); | ||||||||
1528 | if (partial_dividend == 0) { | ||||||||
1529 | Q[i] = 0; | ||||||||
1530 | remainder = 0; | ||||||||
1531 | } else if (partial_dividend < divisor) { | ||||||||
1532 | Q[i] = 0; | ||||||||
1533 | remainder = Lo_32(partial_dividend); | ||||||||
1534 | } else if (partial_dividend == divisor) { | ||||||||
1535 | Q[i] = 1; | ||||||||
1536 | remainder = 0; | ||||||||
1537 | } else { | ||||||||
1538 | Q[i] = Lo_32(partial_dividend / divisor); | ||||||||
1539 | remainder = Lo_32(partial_dividend - (Q[i] * divisor)); | ||||||||
1540 | } | ||||||||
1541 | } | ||||||||
1542 | if (R) | ||||||||
1543 | R[0] = remainder; | ||||||||
1544 | } else { | ||||||||
1545 | // Now we're ready to invoke the Knuth classical divide algorithm. In this | ||||||||
1546 | // case n > 1. | ||||||||
1547 | KnuthDiv(U, V, Q, R, m, n); | ||||||||
1548 | } | ||||||||
1549 | |||||||||
1550 | // If the caller wants the quotient | ||||||||
1551 | if (Quotient) { | ||||||||
1552 | for (unsigned i = 0; i < lhsWords; ++i) | ||||||||
1553 | Quotient[i] = Make_64(Q[i*2+1], Q[i*2]); | ||||||||
1554 | } | ||||||||
1555 | |||||||||
1556 | // If the caller wants the remainder | ||||||||
1557 | if (Remainder) { | ||||||||
1558 | for (unsigned i = 0; i < rhsWords; ++i) | ||||||||
1559 | Remainder[i] = Make_64(R[i*2+1], R[i*2]); | ||||||||
1560 | } | ||||||||
1561 | |||||||||
1562 | // Clean up the memory we allocated. | ||||||||
1563 | if (U != &SPACE[0]) { | ||||||||
1564 | delete [] U; | ||||||||
1565 | delete [] V; | ||||||||
1566 | delete [] Q; | ||||||||
1567 | delete [] R; | ||||||||
1568 | } | ||||||||
1569 | } | ||||||||
1570 | |||||||||
1571 | APInt APInt::udiv(const APInt &RHS) const { | ||||||||
1572 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be the same") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\"" , "llvm/lib/Support/APInt.cpp", 1572, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1573 | |||||||||
1574 | // First, deal with the easy case | ||||||||
1575 | if (isSingleWord()) { | ||||||||
1576 | assert(RHS.U.VAL != 0 && "Divide by zero?")(static_cast <bool> (RHS.U.VAL != 0 && "Divide by zero?" ) ? void (0) : __assert_fail ("RHS.U.VAL != 0 && \"Divide by zero?\"" , "llvm/lib/Support/APInt.cpp", 1576, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1577 | return APInt(BitWidth, U.VAL / RHS.U.VAL); | ||||||||
1578 | } | ||||||||
1579 | |||||||||
1580 | // Get some facts about the LHS and RHS number of bits and words | ||||||||
1581 | unsigned lhsWords = getNumWords(getActiveBits()); | ||||||||
1582 | unsigned rhsBits = RHS.getActiveBits(); | ||||||||
1583 | unsigned rhsWords = getNumWords(rhsBits); | ||||||||
1584 | assert(rhsWords && "Divided by zero???")(static_cast <bool> (rhsWords && "Divided by zero???" ) ? void (0) : __assert_fail ("rhsWords && \"Divided by zero???\"" , "llvm/lib/Support/APInt.cpp", 1584, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1585 | |||||||||
1586 | // Deal with some degenerate cases | ||||||||
1587 | if (!lhsWords) | ||||||||
1588 | // 0 / X ===> 0 | ||||||||
1589 | return APInt(BitWidth, 0); | ||||||||
1590 | if (rhsBits == 1) | ||||||||
1591 | // X / 1 ===> X | ||||||||
1592 | return *this; | ||||||||
1593 | if (lhsWords < rhsWords || this->ult(RHS)) | ||||||||
1594 | // X / Y ===> 0, iff X < Y | ||||||||
1595 | return APInt(BitWidth, 0); | ||||||||
1596 | if (*this == RHS) | ||||||||
1597 | // X / X ===> 1 | ||||||||
1598 | return APInt(BitWidth, 1); | ||||||||
1599 | if (lhsWords == 1) // rhsWords is 1 if lhsWords is 1. | ||||||||
1600 | // All high words are zero, just use native divide | ||||||||
1601 | return APInt(BitWidth, this->U.pVal[0] / RHS.U.pVal[0]); | ||||||||
1602 | |||||||||
1603 | // We have to compute it the hard way. Invoke the Knuth divide algorithm. | ||||||||
1604 | APInt Quotient(BitWidth, 0); // to hold result. | ||||||||
1605 | divide(U.pVal, lhsWords, RHS.U.pVal, rhsWords, Quotient.U.pVal, nullptr); | ||||||||
1606 | return Quotient; | ||||||||
1607 | } | ||||||||
1608 | |||||||||
1609 | APInt APInt::udiv(uint64_t RHS) const { | ||||||||
1610 | assert(RHS != 0 && "Divide by zero?")(static_cast <bool> (RHS != 0 && "Divide by zero?" ) ? void (0) : __assert_fail ("RHS != 0 && \"Divide by zero?\"" , "llvm/lib/Support/APInt.cpp", 1610, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1611 | |||||||||
1612 | // First, deal with the easy case | ||||||||
1613 | if (isSingleWord()) | ||||||||
1614 | return APInt(BitWidth, U.VAL / RHS); | ||||||||
1615 | |||||||||
1616 | // Get some facts about the LHS words. | ||||||||
1617 | unsigned lhsWords = getNumWords(getActiveBits()); | ||||||||
1618 | |||||||||
1619 | // Deal with some degenerate cases | ||||||||
1620 | if (!lhsWords) | ||||||||
1621 | // 0 / X ===> 0 | ||||||||
1622 | return APInt(BitWidth, 0); | ||||||||
1623 | if (RHS == 1) | ||||||||
1624 | // X / 1 ===> X | ||||||||
1625 | return *this; | ||||||||
1626 | if (this->ult(RHS)) | ||||||||
1627 | // X / Y ===> 0, iff X < Y | ||||||||
1628 | return APInt(BitWidth, 0); | ||||||||
1629 | if (*this == RHS) | ||||||||
1630 | // X / X ===> 1 | ||||||||
1631 | return APInt(BitWidth, 1); | ||||||||
1632 | if (lhsWords == 1) // rhsWords is 1 if lhsWords is 1. | ||||||||
1633 | // All high words are zero, just use native divide | ||||||||
1634 | return APInt(BitWidth, this->U.pVal[0] / RHS); | ||||||||
1635 | |||||||||
1636 | // We have to compute it the hard way. Invoke the Knuth divide algorithm. | ||||||||
1637 | APInt Quotient(BitWidth, 0); // to hold result. | ||||||||
1638 | divide(U.pVal, lhsWords, &RHS, 1, Quotient.U.pVal, nullptr); | ||||||||
1639 | return Quotient; | ||||||||
1640 | } | ||||||||
1641 | |||||||||
1642 | APInt APInt::sdiv(const APInt &RHS) const { | ||||||||
1643 | if (isNegative()) { | ||||||||
1644 | if (RHS.isNegative()) | ||||||||
1645 | return (-(*this)).udiv(-RHS); | ||||||||
1646 | return -((-(*this)).udiv(RHS)); | ||||||||
1647 | } | ||||||||
1648 | if (RHS.isNegative()) | ||||||||
1649 | return -(this->udiv(-RHS)); | ||||||||
1650 | return this->udiv(RHS); | ||||||||
1651 | } | ||||||||
1652 | |||||||||
1653 | APInt APInt::sdiv(int64_t RHS) const { | ||||||||
1654 | if (isNegative()) { | ||||||||
1655 | if (RHS < 0) | ||||||||
1656 | return (-(*this)).udiv(-RHS); | ||||||||
1657 | return -((-(*this)).udiv(RHS)); | ||||||||
1658 | } | ||||||||
1659 | if (RHS < 0) | ||||||||
1660 | return -(this->udiv(-RHS)); | ||||||||
1661 | return this->udiv(RHS); | ||||||||
1662 | } | ||||||||
1663 | |||||||||
1664 | APInt APInt::urem(const APInt &RHS) const { | ||||||||
1665 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")(static_cast <bool> (BitWidth == RHS.BitWidth && "Bit widths must be the same") ? void (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\"" , "llvm/lib/Support/APInt.cpp", 1665, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1666 | if (isSingleWord()) { | ||||||||
1667 | assert(RHS.U.VAL != 0 && "Remainder by zero?")(static_cast <bool> (RHS.U.VAL != 0 && "Remainder by zero?" ) ? void (0) : __assert_fail ("RHS.U.VAL != 0 && \"Remainder by zero?\"" , "llvm/lib/Support/APInt.cpp", 1667, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1668 | return APInt(BitWidth, U.VAL % RHS.U.VAL); | ||||||||
1669 | } | ||||||||
1670 | |||||||||
1671 | // Get some facts about the LHS | ||||||||
1672 | unsigned lhsWords = getNumWords(getActiveBits()); | ||||||||
1673 | |||||||||
1674 | // Get some facts about the RHS | ||||||||
1675 | unsigned rhsBits = RHS.getActiveBits(); | ||||||||
1676 | unsigned rhsWords = getNumWords(rhsBits); | ||||||||
1677 | assert(rhsWords && "Performing remainder operation by zero ???")(static_cast <bool> (rhsWords && "Performing remainder operation by zero ???" ) ? void (0) : __assert_fail ("rhsWords && \"Performing remainder operation by zero ???\"" , "llvm/lib/Support/APInt.cpp", 1677, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1678 | |||||||||
1679 | // Check the degenerate cases | ||||||||
1680 | if (lhsWords == 0) | ||||||||
1681 | // 0 % Y ===> 0 | ||||||||
1682 | return APInt(BitWidth, 0); | ||||||||
1683 | if (rhsBits == 1) | ||||||||
1684 | // X % 1 ===> 0 | ||||||||
1685 | return APInt(BitWidth, 0); | ||||||||
1686 | if (lhsWords < rhsWords || this->ult(RHS)) | ||||||||
1687 | // X % Y ===> X, iff X < Y | ||||||||
1688 | return *this; | ||||||||
1689 | if (*this == RHS) | ||||||||
1690 | // X % X == 0; | ||||||||
1691 | return APInt(BitWidth, 0); | ||||||||
1692 | if (lhsWords == 1) | ||||||||
1693 | // All high words are zero, just use native remainder | ||||||||
1694 | return APInt(BitWidth, U.pVal[0] % RHS.U.pVal[0]); | ||||||||
1695 | |||||||||
1696 | // We have to compute it the hard way. Invoke the Knuth divide algorithm. | ||||||||
1697 | APInt Remainder(BitWidth, 0); | ||||||||
1698 | divide(U.pVal, lhsWords, RHS.U.pVal, rhsWords, nullptr, Remainder.U.pVal); | ||||||||
1699 | return Remainder; | ||||||||
1700 | } | ||||||||
1701 | |||||||||
1702 | uint64_t APInt::urem(uint64_t RHS) const { | ||||||||
1703 | assert(RHS != 0 && "Remainder by zero?")(static_cast <bool> (RHS != 0 && "Remainder by zero?" ) ? void (0) : __assert_fail ("RHS != 0 && \"Remainder by zero?\"" , "llvm/lib/Support/APInt.cpp", 1703, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1704 | |||||||||
1705 | if (isSingleWord()) | ||||||||
1706 | return U.VAL % RHS; | ||||||||
1707 | |||||||||
1708 | // Get some facts about the LHS | ||||||||
1709 | unsigned lhsWords = getNumWords(getActiveBits()); | ||||||||
1710 | |||||||||
1711 | // Check the degenerate cases | ||||||||
1712 | if (lhsWords == 0) | ||||||||
1713 | // 0 % Y ===> 0 | ||||||||
1714 | return 0; | ||||||||
1715 | if (RHS == 1) | ||||||||
1716 | // X % 1 ===> 0 | ||||||||
1717 | return 0; | ||||||||
1718 | if (this->ult(RHS)) | ||||||||
1719 | // X % Y ===> X, iff X < Y | ||||||||
1720 | return getZExtValue(); | ||||||||
1721 | if (*this == RHS) | ||||||||
1722 | // X % X == 0; | ||||||||
1723 | return 0; | ||||||||
1724 | if (lhsWords == 1) | ||||||||
1725 | // All high words are zero, just use native remainder | ||||||||
1726 | return U.pVal[0] % RHS; | ||||||||
1727 | |||||||||
1728 | // We have to compute it the hard way. Invoke the Knuth divide algorithm. | ||||||||
1729 | uint64_t Remainder; | ||||||||
1730 | divide(U.pVal, lhsWords, &RHS, 1, nullptr, &Remainder); | ||||||||
1731 | return Remainder; | ||||||||
1732 | } | ||||||||
1733 | |||||||||
1734 | APInt APInt::srem(const APInt &RHS) const { | ||||||||
1735 | if (isNegative()) { | ||||||||
1736 | if (RHS.isNegative()) | ||||||||
1737 | return -((-(*this)).urem(-RHS)); | ||||||||
1738 | return -((-(*this)).urem(RHS)); | ||||||||
1739 | } | ||||||||
1740 | if (RHS.isNegative()) | ||||||||
1741 | return this->urem(-RHS); | ||||||||
1742 | return this->urem(RHS); | ||||||||
1743 | } | ||||||||
1744 | |||||||||
1745 | int64_t APInt::srem(int64_t RHS) const { | ||||||||
1746 | if (isNegative()) { | ||||||||
1747 | if (RHS < 0) | ||||||||
1748 | return -((-(*this)).urem(-RHS)); | ||||||||
1749 | return -((-(*this)).urem(RHS)); | ||||||||
1750 | } | ||||||||
1751 | if (RHS < 0) | ||||||||
1752 | return this->urem(-RHS); | ||||||||
1753 | return this->urem(RHS); | ||||||||
1754 | } | ||||||||
1755 | |||||||||
1756 | void APInt::udivrem(const APInt &LHS, const APInt &RHS, | ||||||||
1757 | APInt &Quotient, APInt &Remainder) { | ||||||||
1758 | assert(LHS.BitWidth == RHS.BitWidth && "Bit widths must be the same")(static_cast <bool> (LHS.BitWidth == RHS.BitWidth && "Bit widths must be the same") ? void (0) : __assert_fail ("LHS.BitWidth == RHS.BitWidth && \"Bit widths must be the same\"" , "llvm/lib/Support/APInt.cpp", 1758, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1759 | unsigned BitWidth = LHS.BitWidth; | ||||||||
1760 | |||||||||
1761 | // First, deal with the easy case | ||||||||
1762 | if (LHS.isSingleWord()) { | ||||||||
1763 | assert(RHS.U.VAL != 0 && "Divide by zero?")(static_cast <bool> (RHS.U.VAL != 0 && "Divide by zero?" ) ? void (0) : __assert_fail ("RHS.U.VAL != 0 && \"Divide by zero?\"" , "llvm/lib/Support/APInt.cpp", 1763, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1764 | uint64_t QuotVal = LHS.U.VAL / RHS.U.VAL; | ||||||||
1765 | uint64_t RemVal = LHS.U.VAL % RHS.U.VAL; | ||||||||
1766 | Quotient = APInt(BitWidth, QuotVal); | ||||||||
1767 | Remainder = APInt(BitWidth, RemVal); | ||||||||
1768 | return; | ||||||||
1769 | } | ||||||||
1770 | |||||||||
1771 | // Get some size facts about the dividend and divisor | ||||||||
1772 | unsigned lhsWords = getNumWords(LHS.getActiveBits()); | ||||||||
1773 | unsigned rhsBits = RHS.getActiveBits(); | ||||||||
1774 | unsigned rhsWords = getNumWords(rhsBits); | ||||||||
1775 | assert(rhsWords && "Performing divrem operation by zero ???")(static_cast <bool> (rhsWords && "Performing divrem operation by zero ???" ) ? void (0) : __assert_fail ("rhsWords && \"Performing divrem operation by zero ???\"" , "llvm/lib/Support/APInt.cpp", 1775, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1776 | |||||||||
1777 | // Check the degenerate cases | ||||||||
1778 | if (lhsWords == 0) { | ||||||||
1779 | Quotient = APInt(BitWidth, 0); // 0 / Y ===> 0 | ||||||||
1780 | Remainder = APInt(BitWidth, 0); // 0 % Y ===> 0 | ||||||||
1781 | return; | ||||||||
1782 | } | ||||||||
1783 | |||||||||
1784 | if (rhsBits == 1) { | ||||||||
1785 | Quotient = LHS; // X / 1 ===> X | ||||||||
1786 | Remainder = APInt(BitWidth, 0); // X % 1 ===> 0 | ||||||||
1787 | } | ||||||||
1788 | |||||||||
1789 | if (lhsWords < rhsWords || LHS.ult(RHS)) { | ||||||||
1790 | Remainder = LHS; // X % Y ===> X, iff X < Y | ||||||||
1791 | Quotient = APInt(BitWidth, 0); // X / Y ===> 0, iff X < Y | ||||||||
1792 | return; | ||||||||
1793 | } | ||||||||
1794 | |||||||||
1795 | if (LHS == RHS) { | ||||||||
1796 | Quotient = APInt(BitWidth, 1); // X / X ===> 1 | ||||||||
1797 | Remainder = APInt(BitWidth, 0); // X % X ===> 0; | ||||||||
1798 | return; | ||||||||
1799 | } | ||||||||
1800 | |||||||||
1801 | // Make sure there is enough space to hold the results. | ||||||||
1802 | // NOTE: This assumes that reallocate won't affect any bits if it doesn't | ||||||||
1803 | // change the size. This is necessary if Quotient or Remainder is aliased | ||||||||
1804 | // with LHS or RHS. | ||||||||
1805 | Quotient.reallocate(BitWidth); | ||||||||
1806 | Remainder.reallocate(BitWidth); | ||||||||
1807 | |||||||||
1808 | if (lhsWords == 1) { // rhsWords is 1 if lhsWords is 1. | ||||||||
1809 | // There is only one word to consider so use the native versions. | ||||||||
1810 | uint64_t lhsValue = LHS.U.pVal[0]; | ||||||||
1811 | uint64_t rhsValue = RHS.U.pVal[0]; | ||||||||
1812 | Quotient = lhsValue / rhsValue; | ||||||||
1813 | Remainder = lhsValue % rhsValue; | ||||||||
1814 | return; | ||||||||
1815 | } | ||||||||
1816 | |||||||||
1817 | // Okay, lets do it the long way | ||||||||
1818 | divide(LHS.U.pVal, lhsWords, RHS.U.pVal, rhsWords, Quotient.U.pVal, | ||||||||
1819 | Remainder.U.pVal); | ||||||||
1820 | // Clear the rest of the Quotient and Remainder. | ||||||||
1821 | std::memset(Quotient.U.pVal + lhsWords, 0, | ||||||||
1822 | (getNumWords(BitWidth) - lhsWords) * APINT_WORD_SIZE); | ||||||||
1823 | std::memset(Remainder.U.pVal + rhsWords, 0, | ||||||||
1824 | (getNumWords(BitWidth) - rhsWords) * APINT_WORD_SIZE); | ||||||||
1825 | } | ||||||||
1826 | |||||||||
1827 | void APInt::udivrem(const APInt &LHS, uint64_t RHS, APInt &Quotient, | ||||||||
1828 | uint64_t &Remainder) { | ||||||||
1829 | assert(RHS != 0 && "Divide by zero?")(static_cast <bool> (RHS != 0 && "Divide by zero?" ) ? void (0) : __assert_fail ("RHS != 0 && \"Divide by zero?\"" , "llvm/lib/Support/APInt.cpp", 1829, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
1830 | unsigned BitWidth = LHS.BitWidth; | ||||||||
1831 | |||||||||
1832 | // First, deal with the easy case | ||||||||
1833 | if (LHS.isSingleWord()) { | ||||||||
1834 | uint64_t QuotVal = LHS.U.VAL / RHS; | ||||||||
1835 | Remainder = LHS.U.VAL % RHS; | ||||||||
1836 | Quotient = APInt(BitWidth, QuotVal); | ||||||||
1837 | return; | ||||||||
1838 | } | ||||||||
1839 | |||||||||
1840 | // Get some size facts about the dividend and divisor | ||||||||
1841 | unsigned lhsWords = getNumWords(LHS.getActiveBits()); | ||||||||
1842 | |||||||||
1843 | // Check the degenerate cases | ||||||||
1844 | if (lhsWords == 0) { | ||||||||
1845 | Quotient = APInt(BitWidth, 0); // 0 / Y ===> 0 | ||||||||
1846 | Remainder = 0; // 0 % Y ===> 0 | ||||||||
1847 | return; | ||||||||
1848 | } | ||||||||
1849 | |||||||||
1850 | if (RHS == 1) { | ||||||||
1851 | Quotient = LHS; // X / 1 ===> X | ||||||||
1852 | Remainder = 0; // X % 1 ===> 0 | ||||||||
1853 | return; | ||||||||
1854 | } | ||||||||
1855 | |||||||||
1856 | if (LHS.ult(RHS)) { | ||||||||
1857 | Remainder = LHS.getZExtValue(); // X % Y ===> X, iff X < Y | ||||||||
1858 | Quotient = APInt(BitWidth, 0); // X / Y ===> 0, iff X < Y | ||||||||
1859 | return; | ||||||||
1860 | } | ||||||||
1861 | |||||||||
1862 | if (LHS == RHS) { | ||||||||
1863 | Quotient = APInt(BitWidth, 1); // X / X ===> 1 | ||||||||
1864 | Remainder = 0; // X % X ===> 0; | ||||||||
1865 | return; | ||||||||
1866 | } | ||||||||
1867 | |||||||||
1868 | // Make sure there is enough space to hold the results. | ||||||||
1869 | // NOTE: This assumes that reallocate won't affect any bits if it doesn't | ||||||||
1870 | // change the size. This is necessary if Quotient is aliased with LHS. | ||||||||
1871 | Quotient.reallocate(BitWidth); | ||||||||
1872 | |||||||||
1873 | if (lhsWords == 1) { // rhsWords is 1 if lhsWords is 1. | ||||||||
1874 | // There is only one word to consider so use the native versions. | ||||||||
1875 | uint64_t lhsValue = LHS.U.pVal[0]; | ||||||||
1876 | Quotient = lhsValue / RHS; | ||||||||
1877 | Remainder = lhsValue % RHS; | ||||||||
1878 | return; | ||||||||
1879 | } | ||||||||
1880 | |||||||||
1881 | // Okay, lets do it the long way | ||||||||
1882 | divide(LHS.U.pVal, lhsWords, &RHS, 1, Quotient.U.pVal, &Remainder); | ||||||||
1883 | // Clear the rest of the Quotient. | ||||||||
1884 | std::memset(Quotient.U.pVal + lhsWords, 0, | ||||||||
1885 | (getNumWords(BitWidth) - lhsWords) * APINT_WORD_SIZE); | ||||||||
1886 | } | ||||||||
1887 | |||||||||
1888 | void APInt::sdivrem(const APInt &LHS, const APInt &RHS, | ||||||||
1889 | APInt &Quotient, APInt &Remainder) { | ||||||||
1890 | if (LHS.isNegative()) { | ||||||||
1891 | if (RHS.isNegative()) | ||||||||
1892 | APInt::udivrem(-LHS, -RHS, Quotient, Remainder); | ||||||||
1893 | else { | ||||||||
1894 | APInt::udivrem(-LHS, RHS, Quotient, Remainder); | ||||||||
1895 | Quotient.negate(); | ||||||||
1896 | } | ||||||||
1897 | Remainder.negate(); | ||||||||
1898 | } else if (RHS.isNegative()) { | ||||||||
1899 | APInt::udivrem(LHS, -RHS, Quotient, Remainder); | ||||||||
1900 | Quotient.negate(); | ||||||||
1901 | } else { | ||||||||
1902 | APInt::udivrem(LHS, RHS, Quotient, Remainder); | ||||||||
1903 | } | ||||||||
1904 | } | ||||||||
1905 | |||||||||
1906 | void APInt::sdivrem(const APInt &LHS, int64_t RHS, | ||||||||
1907 | APInt &Quotient, int64_t &Remainder) { | ||||||||
1908 | uint64_t R = Remainder; | ||||||||
1909 | if (LHS.isNegative()) { | ||||||||
1910 | if (RHS < 0) | ||||||||
1911 | APInt::udivrem(-LHS, -RHS, Quotient, R); | ||||||||
1912 | else { | ||||||||
1913 | APInt::udivrem(-LHS, RHS, Quotient, R); | ||||||||
1914 | Quotient.negate(); | ||||||||
1915 | } | ||||||||
1916 | R = -R; | ||||||||
1917 | } else if (RHS < 0) { | ||||||||
1918 | APInt::udivrem(LHS, -RHS, Quotient, R); | ||||||||
1919 | Quotient.negate(); | ||||||||
1920 | } else { | ||||||||
1921 | APInt::udivrem(LHS, RHS, Quotient, R); | ||||||||
1922 | } | ||||||||
1923 | Remainder = R; | ||||||||
1924 | } | ||||||||
1925 | |||||||||
1926 | APInt APInt::sadd_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1927 | APInt Res = *this+RHS; | ||||||||
1928 | Overflow = isNonNegative() == RHS.isNonNegative() && | ||||||||
1929 | Res.isNonNegative() != isNonNegative(); | ||||||||
1930 | return Res; | ||||||||
1931 | } | ||||||||
1932 | |||||||||
1933 | APInt APInt::uadd_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1934 | APInt Res = *this+RHS; | ||||||||
1935 | Overflow = Res.ult(RHS); | ||||||||
1936 | return Res; | ||||||||
1937 | } | ||||||||
1938 | |||||||||
1939 | APInt APInt::ssub_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1940 | APInt Res = *this - RHS; | ||||||||
1941 | Overflow = isNonNegative() != RHS.isNonNegative() && | ||||||||
1942 | Res.isNonNegative() != isNonNegative(); | ||||||||
1943 | return Res; | ||||||||
1944 | } | ||||||||
1945 | |||||||||
1946 | APInt APInt::usub_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1947 | APInt Res = *this-RHS; | ||||||||
1948 | Overflow = Res.ugt(*this); | ||||||||
1949 | return Res; | ||||||||
1950 | } | ||||||||
1951 | |||||||||
1952 | APInt APInt::sdiv_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1953 | // MININT/-1 --> overflow. | ||||||||
1954 | Overflow = isMinSignedValue() && RHS.isAllOnes(); | ||||||||
1955 | return sdiv(RHS); | ||||||||
1956 | } | ||||||||
1957 | |||||||||
1958 | APInt APInt::smul_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1959 | APInt Res = *this * RHS; | ||||||||
1960 | |||||||||
1961 | if (RHS != 0) | ||||||||
1962 | Overflow = Res.sdiv(RHS) != *this || | ||||||||
1963 | (isMinSignedValue() && RHS.isAllOnes()); | ||||||||
1964 | else | ||||||||
1965 | Overflow = false; | ||||||||
1966 | return Res; | ||||||||
1967 | } | ||||||||
1968 | |||||||||
1969 | APInt APInt::umul_ov(const APInt &RHS, bool &Overflow) const { | ||||||||
1970 | if (countl_zero() + RHS.countl_zero() + 2 <= BitWidth) { | ||||||||
1971 | Overflow = true; | ||||||||
1972 | return *this * RHS; | ||||||||
1973 | } | ||||||||
1974 | |||||||||
1975 | APInt Res = lshr(1) * RHS; | ||||||||
1976 | Overflow = Res.isNegative(); | ||||||||
1977 | Res <<= 1; | ||||||||
1978 | if ((*this)[0]) { | ||||||||
1979 | Res += RHS; | ||||||||
1980 | if (Res.ult(RHS)) | ||||||||
1981 | Overflow = true; | ||||||||
1982 | } | ||||||||
1983 | return Res; | ||||||||
1984 | } | ||||||||
1985 | |||||||||
1986 | APInt APInt::sshl_ov(const APInt &ShAmt, bool &Overflow) const { | ||||||||
1987 | Overflow = ShAmt.uge(getBitWidth()); | ||||||||
1988 | if (Overflow) | ||||||||
1989 | return APInt(BitWidth, 0); | ||||||||
1990 | |||||||||
1991 | if (isNonNegative()) // Don't allow sign change. | ||||||||
1992 | Overflow = ShAmt.uge(countl_zero()); | ||||||||
1993 | else | ||||||||
1994 | Overflow = ShAmt.uge(countl_one()); | ||||||||
1995 | |||||||||
1996 | return *this << ShAmt; | ||||||||
1997 | } | ||||||||
1998 | |||||||||
1999 | APInt APInt::ushl_ov(const APInt &ShAmt, bool &Overflow) const { | ||||||||
2000 | Overflow = ShAmt.uge(getBitWidth()); | ||||||||
2001 | if (Overflow) | ||||||||
2002 | return APInt(BitWidth, 0); | ||||||||
2003 | |||||||||
2004 | Overflow = ShAmt.ugt(countl_zero()); | ||||||||
2005 | |||||||||
2006 | return *this << ShAmt; | ||||||||
2007 | } | ||||||||
2008 | |||||||||
2009 | APInt APInt::sadd_sat(const APInt &RHS) const { | ||||||||
2010 | bool Overflow; | ||||||||
2011 | APInt Res = sadd_ov(RHS, Overflow); | ||||||||
2012 | if (!Overflow) | ||||||||
2013 | return Res; | ||||||||
2014 | |||||||||
2015 | return isNegative() ? APInt::getSignedMinValue(BitWidth) | ||||||||
2016 | : APInt::getSignedMaxValue(BitWidth); | ||||||||
2017 | } | ||||||||
2018 | |||||||||
2019 | APInt APInt::uadd_sat(const APInt &RHS) const { | ||||||||
2020 | bool Overflow; | ||||||||
2021 | APInt Res = uadd_ov(RHS, Overflow); | ||||||||
2022 | if (!Overflow) | ||||||||
2023 | return Res; | ||||||||
2024 | |||||||||
2025 | return APInt::getMaxValue(BitWidth); | ||||||||
2026 | } | ||||||||
2027 | |||||||||
2028 | APInt APInt::ssub_sat(const APInt &RHS) const { | ||||||||
2029 | bool Overflow; | ||||||||
2030 | APInt Res = ssub_ov(RHS, Overflow); | ||||||||
2031 | if (!Overflow) | ||||||||
2032 | return Res; | ||||||||
2033 | |||||||||
2034 | return isNegative() ? APInt::getSignedMinValue(BitWidth) | ||||||||
2035 | : APInt::getSignedMaxValue(BitWidth); | ||||||||
2036 | } | ||||||||
2037 | |||||||||
2038 | APInt APInt::usub_sat(const APInt &RHS) const { | ||||||||
2039 | bool Overflow; | ||||||||
2040 | APInt Res = usub_ov(RHS, Overflow); | ||||||||
2041 | if (!Overflow) | ||||||||
2042 | return Res; | ||||||||
2043 | |||||||||
2044 | return APInt(BitWidth, 0); | ||||||||
2045 | } | ||||||||
2046 | |||||||||
2047 | APInt APInt::smul_sat(const APInt &RHS) const { | ||||||||
2048 | bool Overflow; | ||||||||
2049 | APInt Res = smul_ov(RHS, Overflow); | ||||||||
2050 | if (!Overflow) | ||||||||
2051 | return Res; | ||||||||
2052 | |||||||||
2053 | // The result is negative if one and only one of inputs is negative. | ||||||||
2054 | bool ResIsNegative = isNegative() ^ RHS.isNegative(); | ||||||||
2055 | |||||||||
2056 | return ResIsNegative ? APInt::getSignedMinValue(BitWidth) | ||||||||
2057 | : APInt::getSignedMaxValue(BitWidth); | ||||||||
2058 | } | ||||||||
2059 | |||||||||
2060 | APInt APInt::umul_sat(const APInt &RHS) const { | ||||||||
2061 | bool Overflow; | ||||||||
2062 | APInt Res = umul_ov(RHS, Overflow); | ||||||||
2063 | if (!Overflow) | ||||||||
2064 | return Res; | ||||||||
2065 | |||||||||
2066 | return APInt::getMaxValue(BitWidth); | ||||||||
2067 | } | ||||||||
2068 | |||||||||
2069 | APInt APInt::sshl_sat(const APInt &RHS) const { | ||||||||
2070 | bool Overflow; | ||||||||
2071 | APInt Res = sshl_ov(RHS, Overflow); | ||||||||
2072 | if (!Overflow) | ||||||||
2073 | return Res; | ||||||||
2074 | |||||||||
2075 | return isNegative() ? APInt::getSignedMinValue(BitWidth) | ||||||||
2076 | : APInt::getSignedMaxValue(BitWidth); | ||||||||
2077 | } | ||||||||
2078 | |||||||||
2079 | APInt APInt::ushl_sat(const APInt &RHS) const { | ||||||||
2080 | bool Overflow; | ||||||||
2081 | APInt Res = ushl_ov(RHS, Overflow); | ||||||||
2082 | if (!Overflow) | ||||||||
2083 | return Res; | ||||||||
2084 | |||||||||
2085 | return APInt::getMaxValue(BitWidth); | ||||||||
2086 | } | ||||||||
2087 | |||||||||
2088 | void APInt::fromString(unsigned numbits, StringRef str, uint8_t radix) { | ||||||||
2089 | // Check our assumptions here | ||||||||
2090 | assert(!str.empty() && "Invalid string length")(static_cast <bool> (!str.empty() && "Invalid string length" ) ? void (0) : __assert_fail ("!str.empty() && \"Invalid string length\"" , "llvm/lib/Support/APInt.cpp", 2090, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2091 | assert((radix == 10 || radix == 8 || radix == 16 || radix == 2 ||(static_cast <bool> ((radix == 10 || radix == 8 || radix == 16 || radix == 2 || radix == 36) && "Radix should be 2, 8, 10, 16, or 36!" ) ? void (0) : __assert_fail ("(radix == 10 || radix == 8 || radix == 16 || radix == 2 || radix == 36) && \"Radix should be 2, 8, 10, 16, or 36!\"" , "llvm/lib/Support/APInt.cpp", 2093, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2092 | radix == 36) &&(static_cast <bool> ((radix == 10 || radix == 8 || radix == 16 || radix == 2 || radix == 36) && "Radix should be 2, 8, 10, 16, or 36!" ) ? void (0) : __assert_fail ("(radix == 10 || radix == 8 || radix == 16 || radix == 2 || radix == 36) && \"Radix should be 2, 8, 10, 16, or 36!\"" , "llvm/lib/Support/APInt.cpp", 2093, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2093 | "Radix should be 2, 8, 10, 16, or 36!")(static_cast <bool> ((radix == 10 || radix == 8 || radix == 16 || radix == 2 || radix == 36) && "Radix should be 2, 8, 10, 16, or 36!" ) ? void (0) : __assert_fail ("(radix == 10 || radix == 8 || radix == 16 || radix == 2 || radix == 36) && \"Radix should be 2, 8, 10, 16, or 36!\"" , "llvm/lib/Support/APInt.cpp", 2093, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2094 | |||||||||
2095 | StringRef::iterator p = str.begin(); | ||||||||
2096 | size_t slen = str.size(); | ||||||||
2097 | bool isNeg = *p == '-'; | ||||||||
2098 | if (*p == '-' || *p == '+') { | ||||||||
2099 | p++; | ||||||||
2100 | slen--; | ||||||||
2101 | assert(slen && "String is only a sign, needs a value.")(static_cast <bool> (slen && "String is only a sign, needs a value." ) ? void (0) : __assert_fail ("slen && \"String is only a sign, needs a value.\"" , "llvm/lib/Support/APInt.cpp", 2101, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2102 | } | ||||||||
2103 | assert((slen <= numbits || radix != 2) && "Insufficient bit width")(static_cast <bool> ((slen <= numbits || radix != 2) && "Insufficient bit width") ? void (0) : __assert_fail ("(slen <= numbits || radix != 2) && \"Insufficient bit width\"" , "llvm/lib/Support/APInt.cpp", 2103, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2104 | assert(((slen-1)*3 <= numbits || radix != 8) && "Insufficient bit width")(static_cast <bool> (((slen-1)*3 <= numbits || radix != 8) && "Insufficient bit width") ? void (0) : __assert_fail ("((slen-1)*3 <= numbits || radix != 8) && \"Insufficient bit width\"" , "llvm/lib/Support/APInt.cpp", 2104, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2105 | assert(((slen-1)*4 <= numbits || radix != 16) && "Insufficient bit width")(static_cast <bool> (((slen-1)*4 <= numbits || radix != 16) && "Insufficient bit width") ? void (0) : __assert_fail ("((slen-1)*4 <= numbits || radix != 16) && \"Insufficient bit width\"" , "llvm/lib/Support/APInt.cpp", 2105, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2106 | assert((((slen-1)*64)/22 <= numbits || radix != 10) &&(static_cast <bool> ((((slen-1)*64)/22 <= numbits || radix != 10) && "Insufficient bit width") ? void (0) : __assert_fail ("(((slen-1)*64)/22 <= numbits || radix != 10) && \"Insufficient bit width\"" , "llvm/lib/Support/APInt.cpp", 2107, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2107 | "Insufficient bit width")(static_cast <bool> ((((slen-1)*64)/22 <= numbits || radix != 10) && "Insufficient bit width") ? void (0) : __assert_fail ("(((slen-1)*64)/22 <= numbits || radix != 10) && \"Insufficient bit width\"" , "llvm/lib/Support/APInt.cpp", 2107, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2108 | |||||||||
2109 | // Allocate memory if needed | ||||||||
2110 | if (isSingleWord()) | ||||||||
2111 | U.VAL = 0; | ||||||||
2112 | else | ||||||||
2113 | U.pVal = getClearedMemory(getNumWords()); | ||||||||
2114 | |||||||||
2115 | // Figure out if we can shift instead of multiply | ||||||||
2116 | unsigned shift = (radix == 16 ? 4 : radix == 8 ? 3 : radix == 2 ? 1 : 0); | ||||||||
2117 | |||||||||
2118 | // Enter digit traversal loop | ||||||||
2119 | for (StringRef::iterator e = str.end(); p != e; ++p) { | ||||||||
2120 | unsigned digit = getDigit(*p, radix); | ||||||||
2121 | assert(digit < radix && "Invalid character in digit string")(static_cast <bool> (digit < radix && "Invalid character in digit string" ) ? void (0) : __assert_fail ("digit < radix && \"Invalid character in digit string\"" , "llvm/lib/Support/APInt.cpp", 2121, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2122 | |||||||||
2123 | // Shift or multiply the value by the radix | ||||||||
2124 | if (slen > 1) { | ||||||||
2125 | if (shift) | ||||||||
2126 | *this <<= shift; | ||||||||
2127 | else | ||||||||
2128 | *this *= radix; | ||||||||
2129 | } | ||||||||
2130 | |||||||||
2131 | // Add in the digit we just interpreted | ||||||||
2132 | *this += digit; | ||||||||
2133 | } | ||||||||
2134 | // If its negative, put it in two's complement form | ||||||||
2135 | if (isNeg) | ||||||||
2136 | this->negate(); | ||||||||
2137 | } | ||||||||
2138 | |||||||||
2139 | void APInt::toString(SmallVectorImpl<char> &Str, unsigned Radix, | ||||||||
2140 | bool Signed, bool formatAsCLiteral) const { | ||||||||
2141 | assert((Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 ||(static_cast <bool> ((Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 || Radix == 36) && "Radix should be 2, 8, 10, 16, or 36!" ) ? void (0) : __assert_fail ("(Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 || Radix == 36) && \"Radix should be 2, 8, 10, 16, or 36!\"" , "llvm/lib/Support/APInt.cpp", 2143, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2142 | Radix == 36) &&(static_cast <bool> ((Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 || Radix == 36) && "Radix should be 2, 8, 10, 16, or 36!" ) ? void (0) : __assert_fail ("(Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 || Radix == 36) && \"Radix should be 2, 8, 10, 16, or 36!\"" , "llvm/lib/Support/APInt.cpp", 2143, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2143 | "Radix should be 2, 8, 10, 16, or 36!")(static_cast <bool> ((Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 || Radix == 36) && "Radix should be 2, 8, 10, 16, or 36!" ) ? void (0) : __assert_fail ("(Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2 || Radix == 36) && \"Radix should be 2, 8, 10, 16, or 36!\"" , "llvm/lib/Support/APInt.cpp", 2143, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2144 | |||||||||
2145 | const char *Prefix = ""; | ||||||||
2146 | if (formatAsCLiteral) { | ||||||||
2147 | switch (Radix) { | ||||||||
2148 | case 2: | ||||||||
2149 | // Binary literals are a non-standard extension added in gcc 4.3: | ||||||||
2150 | // http://gcc.gnu.org/onlinedocs/gcc-4.3.0/gcc/Binary-constants.html | ||||||||
2151 | Prefix = "0b"; | ||||||||
2152 | break; | ||||||||
2153 | case 8: | ||||||||
2154 | Prefix = "0"; | ||||||||
2155 | break; | ||||||||
2156 | case 10: | ||||||||
2157 | break; // No prefix | ||||||||
2158 | case 16: | ||||||||
2159 | Prefix = "0x"; | ||||||||
2160 | break; | ||||||||
2161 | default: | ||||||||
2162 | llvm_unreachable("Invalid radix!")::llvm::llvm_unreachable_internal("Invalid radix!", "llvm/lib/Support/APInt.cpp" , 2162); | ||||||||
2163 | } | ||||||||
2164 | } | ||||||||
2165 | |||||||||
2166 | // First, check for a zero value and just short circuit the logic below. | ||||||||
2167 | if (isZero()) { | ||||||||
2168 | while (*Prefix) { | ||||||||
2169 | Str.push_back(*Prefix); | ||||||||
2170 | ++Prefix; | ||||||||
2171 | }; | ||||||||
2172 | Str.push_back('0'); | ||||||||
2173 | return; | ||||||||
2174 | } | ||||||||
2175 | |||||||||
2176 | static const char Digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; | ||||||||
2177 | |||||||||
2178 | if (isSingleWord()) { | ||||||||
2179 | char Buffer[65]; | ||||||||
2180 | char *BufPtr = std::end(Buffer); | ||||||||
2181 | |||||||||
2182 | uint64_t N; | ||||||||
2183 | if (!Signed) { | ||||||||
2184 | N = getZExtValue(); | ||||||||
2185 | } else { | ||||||||
2186 | int64_t I = getSExtValue(); | ||||||||
2187 | if (I >= 0) { | ||||||||
2188 | N = I; | ||||||||
2189 | } else { | ||||||||
2190 | Str.push_back('-'); | ||||||||
2191 | N = -(uint64_t)I; | ||||||||
2192 | } | ||||||||
2193 | } | ||||||||
2194 | |||||||||
2195 | while (*Prefix) { | ||||||||
2196 | Str.push_back(*Prefix); | ||||||||
2197 | ++Prefix; | ||||||||
2198 | }; | ||||||||
2199 | |||||||||
2200 | while (N) { | ||||||||
2201 | *--BufPtr = Digits[N % Radix]; | ||||||||
2202 | N /= Radix; | ||||||||
2203 | } | ||||||||
2204 | Str.append(BufPtr, std::end(Buffer)); | ||||||||
2205 | return; | ||||||||
2206 | } | ||||||||
2207 | |||||||||
2208 | APInt Tmp(*this); | ||||||||
2209 | |||||||||
2210 | if (Signed && isNegative()) { | ||||||||
2211 | // They want to print the signed version and it is a negative value | ||||||||
2212 | // Flip the bits and add one to turn it into the equivalent positive | ||||||||
2213 | // value and put a '-' in the result. | ||||||||
2214 | Tmp.negate(); | ||||||||
2215 | Str.push_back('-'); | ||||||||
2216 | } | ||||||||
2217 | |||||||||
2218 | while (*Prefix) { | ||||||||
2219 | Str.push_back(*Prefix); | ||||||||
2220 | ++Prefix; | ||||||||
2221 | }; | ||||||||
2222 | |||||||||
2223 | // We insert the digits backward, then reverse them to get the right order. | ||||||||
2224 | unsigned StartDig = Str.size(); | ||||||||
2225 | |||||||||
2226 | // For the 2, 8 and 16 bit cases, we can just shift instead of divide | ||||||||
2227 | // because the number of bits per digit (1, 3 and 4 respectively) divides | ||||||||
2228 | // equally. We just shift until the value is zero. | ||||||||
2229 | if (Radix == 2 || Radix == 8 || Radix == 16) { | ||||||||
2230 | // Just shift tmp right for each digit width until it becomes zero | ||||||||
2231 | unsigned ShiftAmt = (Radix == 16 ? 4 : (Radix == 8 ? 3 : 1)); | ||||||||
2232 | unsigned MaskAmt = Radix - 1; | ||||||||
2233 | |||||||||
2234 | while (Tmp.getBoolValue()) { | ||||||||
2235 | unsigned Digit = unsigned(Tmp.getRawData()[0]) & MaskAmt; | ||||||||
2236 | Str.push_back(Digits[Digit]); | ||||||||
2237 | Tmp.lshrInPlace(ShiftAmt); | ||||||||
2238 | } | ||||||||
2239 | } else { | ||||||||
2240 | while (Tmp.getBoolValue()) { | ||||||||
2241 | uint64_t Digit; | ||||||||
2242 | udivrem(Tmp, Radix, Tmp, Digit); | ||||||||
2243 | assert(Digit < Radix && "divide failed")(static_cast <bool> (Digit < Radix && "divide failed" ) ? void (0) : __assert_fail ("Digit < Radix && \"divide failed\"" , "llvm/lib/Support/APInt.cpp", 2243, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2244 | Str.push_back(Digits[Digit]); | ||||||||
2245 | } | ||||||||
2246 | } | ||||||||
2247 | |||||||||
2248 | // Reverse the digits before returning. | ||||||||
2249 | std::reverse(Str.begin()+StartDig, Str.end()); | ||||||||
2250 | } | ||||||||
2251 | |||||||||
2252 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) | ||||||||
2253 | LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void APInt::dump() const { | ||||||||
2254 | SmallString<40> S, U; | ||||||||
2255 | this->toStringUnsigned(U); | ||||||||
2256 | this->toStringSigned(S); | ||||||||
2257 | dbgs() << "APInt(" << BitWidth << "b, " | ||||||||
2258 | << U << "u " << S << "s)\n"; | ||||||||
2259 | } | ||||||||
2260 | #endif | ||||||||
2261 | |||||||||
2262 | void APInt::print(raw_ostream &OS, bool isSigned) const { | ||||||||
2263 | SmallString<40> S; | ||||||||
2264 | this->toString(S, 10, isSigned, /* formatAsCLiteral = */false); | ||||||||
2265 | OS << S; | ||||||||
2266 | } | ||||||||
2267 | |||||||||
2268 | // This implements a variety of operations on a representation of | ||||||||
2269 | // arbitrary precision, two's-complement, bignum integer values. | ||||||||
2270 | |||||||||
2271 | // Assumed by lowHalf, highHalf, partMSB and partLSB. A fairly safe | ||||||||
2272 | // and unrestricting assumption. | ||||||||
2273 | static_assert(APInt::APINT_BITS_PER_WORD % 2 == 0, | ||||||||
2274 | "Part width must be divisible by 2!"); | ||||||||
2275 | |||||||||
2276 | // Returns the integer part with the least significant BITS set. | ||||||||
2277 | // BITS cannot be zero. | ||||||||
2278 | static inline APInt::WordType lowBitMask(unsigned bits) { | ||||||||
2279 | assert(bits != 0 && bits <= APInt::APINT_BITS_PER_WORD)(static_cast <bool> (bits != 0 && bits <= APInt ::APINT_BITS_PER_WORD) ? void (0) : __assert_fail ("bits != 0 && bits <= APInt::APINT_BITS_PER_WORD" , "llvm/lib/Support/APInt.cpp", 2279, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2280 | return ~(APInt::WordType) 0 >> (APInt::APINT_BITS_PER_WORD - bits); | ||||||||
2281 | } | ||||||||
2282 | |||||||||
2283 | /// Returns the value of the lower half of PART. | ||||||||
2284 | static inline APInt::WordType lowHalf(APInt::WordType part) { | ||||||||
2285 | return part & lowBitMask(APInt::APINT_BITS_PER_WORD / 2); | ||||||||
2286 | } | ||||||||
2287 | |||||||||
2288 | /// Returns the value of the upper half of PART. | ||||||||
2289 | static inline APInt::WordType highHalf(APInt::WordType part) { | ||||||||
2290 | return part >> (APInt::APINT_BITS_PER_WORD / 2); | ||||||||
2291 | } | ||||||||
2292 | |||||||||
2293 | /// Sets the least significant part of a bignum to the input value, and zeroes | ||||||||
2294 | /// out higher parts. | ||||||||
2295 | void APInt::tcSet(WordType *dst, WordType part, unsigned parts) { | ||||||||
2296 | assert(parts > 0)(static_cast <bool> (parts > 0) ? void (0) : __assert_fail ("parts > 0", "llvm/lib/Support/APInt.cpp", 2296, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2297 | dst[0] = part; | ||||||||
2298 | for (unsigned i = 1; i < parts; i++) | ||||||||
2299 | dst[i] = 0; | ||||||||
2300 | } | ||||||||
2301 | |||||||||
2302 | /// Assign one bignum to another. | ||||||||
2303 | void APInt::tcAssign(WordType *dst, const WordType *src, unsigned parts) { | ||||||||
2304 | for (unsigned i = 0; i < parts; i++) | ||||||||
2305 | dst[i] = src[i]; | ||||||||
2306 | } | ||||||||
2307 | |||||||||
2308 | /// Returns true if a bignum is zero, false otherwise. | ||||||||
2309 | bool APInt::tcIsZero(const WordType *src, unsigned parts) { | ||||||||
2310 | for (unsigned i = 0; i < parts; i++) | ||||||||
2311 | if (src[i]) | ||||||||
2312 | return false; | ||||||||
2313 | |||||||||
2314 | return true; | ||||||||
2315 | } | ||||||||
2316 | |||||||||
2317 | /// Extract the given bit of a bignum; returns 0 or 1. | ||||||||
2318 | int APInt::tcExtractBit(const WordType *parts, unsigned bit) { | ||||||||
2319 | return (parts[whichWord(bit)] & maskBit(bit)) != 0; | ||||||||
2320 | } | ||||||||
2321 | |||||||||
2322 | /// Set the given bit of a bignum. | ||||||||
2323 | void APInt::tcSetBit(WordType *parts, unsigned bit) { | ||||||||
2324 | parts[whichWord(bit)] |= maskBit(bit); | ||||||||
2325 | } | ||||||||
2326 | |||||||||
2327 | /// Clears the given bit of a bignum. | ||||||||
2328 | void APInt::tcClearBit(WordType *parts, unsigned bit) { | ||||||||
2329 | parts[whichWord(bit)] &= ~maskBit(bit); | ||||||||
2330 | } | ||||||||
2331 | |||||||||
2332 | /// Returns the bit number of the least significant set bit of a number. If the | ||||||||
2333 | /// input number has no bits set UINT_MAX is returned. | ||||||||
2334 | unsigned APInt::tcLSB(const WordType *parts, unsigned n) { | ||||||||
2335 | for (unsigned i = 0; i < n; i++) { | ||||||||
2336 | if (parts[i] != 0) { | ||||||||
2337 | unsigned lsb = llvm::countr_zero(parts[i]); | ||||||||
2338 | return lsb + i * APINT_BITS_PER_WORD; | ||||||||
2339 | } | ||||||||
2340 | } | ||||||||
2341 | |||||||||
2342 | return UINT_MAX(2147483647 *2U +1U); | ||||||||
2343 | } | ||||||||
2344 | |||||||||
2345 | /// Returns the bit number of the most significant set bit of a number. | ||||||||
2346 | /// If the input number has no bits set UINT_MAX is returned. | ||||||||
2347 | unsigned APInt::tcMSB(const WordType *parts, unsigned n) { | ||||||||
2348 | do { | ||||||||
2349 | --n; | ||||||||
2350 | |||||||||
2351 | if (parts[n] != 0) { | ||||||||
2352 | static_assert(sizeof(parts[n]) <= sizeof(uint64_t)); | ||||||||
2353 | unsigned msb = llvm::Log2_64(parts[n]); | ||||||||
2354 | |||||||||
2355 | return msb + n * APINT_BITS_PER_WORD; | ||||||||
2356 | } | ||||||||
2357 | } while (n); | ||||||||
2358 | |||||||||
2359 | return UINT_MAX(2147483647 *2U +1U); | ||||||||
2360 | } | ||||||||
2361 | |||||||||
2362 | /// Copy the bit vector of width srcBITS from SRC, starting at bit srcLSB, to | ||||||||
2363 | /// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least | ||||||||
2364 | /// significant bit of DST. All high bits above srcBITS in DST are zero-filled. | ||||||||
2365 | /// */ | ||||||||
2366 | void | ||||||||
2367 | APInt::tcExtract(WordType *dst, unsigned dstCount, const WordType *src, | ||||||||
2368 | unsigned srcBits, unsigned srcLSB) { | ||||||||
2369 | unsigned dstParts = (srcBits + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD; | ||||||||
2370 | assert(dstParts <= dstCount)(static_cast <bool> (dstParts <= dstCount) ? void (0 ) : __assert_fail ("dstParts <= dstCount", "llvm/lib/Support/APInt.cpp" , 2370, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2371 | |||||||||
2372 | unsigned firstSrcPart = srcLSB / APINT_BITS_PER_WORD; | ||||||||
2373 | tcAssign(dst, src + firstSrcPart, dstParts); | ||||||||
2374 | |||||||||
2375 | unsigned shift = srcLSB % APINT_BITS_PER_WORD; | ||||||||
2376 | tcShiftRight(dst, dstParts, shift); | ||||||||
2377 | |||||||||
2378 | // We now have (dstParts * APINT_BITS_PER_WORD - shift) bits from SRC | ||||||||
2379 | // in DST. If this is less that srcBits, append the rest, else | ||||||||
2380 | // clear the high bits. | ||||||||
2381 | unsigned n = dstParts * APINT_BITS_PER_WORD - shift; | ||||||||
2382 | if (n < srcBits) { | ||||||||
2383 | WordType mask = lowBitMask (srcBits - n); | ||||||||
2384 | dst[dstParts - 1] |= ((src[firstSrcPart + dstParts] & mask) | ||||||||
2385 | << n % APINT_BITS_PER_WORD); | ||||||||
2386 | } else if (n > srcBits) { | ||||||||
2387 | if (srcBits % APINT_BITS_PER_WORD) | ||||||||
2388 | dst[dstParts - 1] &= lowBitMask (srcBits % APINT_BITS_PER_WORD); | ||||||||
2389 | } | ||||||||
2390 | |||||||||
2391 | // Clear high parts. | ||||||||
2392 | while (dstParts < dstCount) | ||||||||
2393 | dst[dstParts++] = 0; | ||||||||
2394 | } | ||||||||
2395 | |||||||||
2396 | //// DST += RHS + C where C is zero or one. Returns the carry flag. | ||||||||
2397 | APInt::WordType APInt::tcAdd(WordType *dst, const WordType *rhs, | ||||||||
2398 | WordType c, unsigned parts) { | ||||||||
2399 | assert(c <= 1)(static_cast <bool> (c <= 1) ? void (0) : __assert_fail ("c <= 1", "llvm/lib/Support/APInt.cpp", 2399, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2400 | |||||||||
2401 | for (unsigned i = 0; i < parts; i++) { | ||||||||
2402 | WordType l = dst[i]; | ||||||||
2403 | if (c) { | ||||||||
2404 | dst[i] += rhs[i] + 1; | ||||||||
2405 | c = (dst[i] <= l); | ||||||||
2406 | } else { | ||||||||
2407 | dst[i] += rhs[i]; | ||||||||
2408 | c = (dst[i] < l); | ||||||||
2409 | } | ||||||||
2410 | } | ||||||||
2411 | |||||||||
2412 | return c; | ||||||||
2413 | } | ||||||||
2414 | |||||||||
2415 | /// This function adds a single "word" integer, src, to the multiple | ||||||||
2416 | /// "word" integer array, dst[]. dst[] is modified to reflect the addition and | ||||||||
2417 | /// 1 is returned if there is a carry out, otherwise 0 is returned. | ||||||||
2418 | /// @returns the carry of the addition. | ||||||||
2419 | APInt::WordType APInt::tcAddPart(WordType *dst, WordType src, | ||||||||
2420 | unsigned parts) { | ||||||||
2421 | for (unsigned i = 0; i < parts; ++i) { | ||||||||
2422 | dst[i] += src; | ||||||||
2423 | if (dst[i] >= src) | ||||||||
2424 | return 0; // No need to carry so exit early. | ||||||||
2425 | src = 1; // Carry one to next digit. | ||||||||
2426 | } | ||||||||
2427 | |||||||||
2428 | return 1; | ||||||||
2429 | } | ||||||||
2430 | |||||||||
2431 | /// DST -= RHS + C where C is zero or one. Returns the carry flag. | ||||||||
2432 | APInt::WordType APInt::tcSubtract(WordType *dst, const WordType *rhs, | ||||||||
2433 | WordType c, unsigned parts) { | ||||||||
2434 | assert(c <= 1)(static_cast <bool> (c <= 1) ? void (0) : __assert_fail ("c <= 1", "llvm/lib/Support/APInt.cpp", 2434, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2435 | |||||||||
2436 | for (unsigned i = 0; i < parts; i++) { | ||||||||
2437 | WordType l = dst[i]; | ||||||||
2438 | if (c) { | ||||||||
2439 | dst[i] -= rhs[i] + 1; | ||||||||
2440 | c = (dst[i] >= l); | ||||||||
2441 | } else { | ||||||||
2442 | dst[i] -= rhs[i]; | ||||||||
2443 | c = (dst[i] > l); | ||||||||
2444 | } | ||||||||
2445 | } | ||||||||
2446 | |||||||||
2447 | return c; | ||||||||
2448 | } | ||||||||
2449 | |||||||||
2450 | /// This function subtracts a single "word" (64-bit word), src, from | ||||||||
2451 | /// the multi-word integer array, dst[], propagating the borrowed 1 value until | ||||||||
2452 | /// no further borrowing is needed or it runs out of "words" in dst. The result | ||||||||
2453 | /// is 1 if "borrowing" exhausted the digits in dst, or 0 if dst was not | ||||||||
2454 | /// exhausted. In other words, if src > dst then this function returns 1, | ||||||||
2455 | /// otherwise 0. | ||||||||
2456 | /// @returns the borrow out of the subtraction | ||||||||
2457 | APInt::WordType APInt::tcSubtractPart(WordType *dst, WordType src, | ||||||||
2458 | unsigned parts) { | ||||||||
2459 | for (unsigned i = 0; i < parts; ++i) { | ||||||||
2460 | WordType Dst = dst[i]; | ||||||||
2461 | dst[i] -= src; | ||||||||
2462 | if (src <= Dst) | ||||||||
2463 | return 0; // No need to borrow so exit early. | ||||||||
2464 | src = 1; // We have to "borrow 1" from next "word" | ||||||||
2465 | } | ||||||||
2466 | |||||||||
2467 | return 1; | ||||||||
2468 | } | ||||||||
2469 | |||||||||
2470 | /// Negate a bignum in-place. | ||||||||
2471 | void APInt::tcNegate(WordType *dst, unsigned parts) { | ||||||||
2472 | tcComplement(dst, parts); | ||||||||
2473 | tcIncrement(dst, parts); | ||||||||
2474 | } | ||||||||
2475 | |||||||||
2476 | /// DST += SRC * MULTIPLIER + CARRY if add is true | ||||||||
2477 | /// DST = SRC * MULTIPLIER + CARRY if add is false | ||||||||
2478 | /// Requires 0 <= DSTPARTS <= SRCPARTS + 1. If DST overlaps SRC | ||||||||
2479 | /// they must start at the same point, i.e. DST == SRC. | ||||||||
2480 | /// If DSTPARTS == SRCPARTS + 1 no overflow occurs and zero is | ||||||||
2481 | /// returned. Otherwise DST is filled with the least significant | ||||||||
2482 | /// DSTPARTS parts of the result, and if all of the omitted higher | ||||||||
2483 | /// parts were zero return zero, otherwise overflow occurred and | ||||||||
2484 | /// return one. | ||||||||
2485 | int APInt::tcMultiplyPart(WordType *dst, const WordType *src, | ||||||||
2486 | WordType multiplier, WordType carry, | ||||||||
2487 | unsigned srcParts, unsigned dstParts, | ||||||||
2488 | bool add) { | ||||||||
2489 | // Otherwise our writes of DST kill our later reads of SRC. | ||||||||
2490 | assert(dst <= src || dst >= src + srcParts)(static_cast <bool> (dst <= src || dst >= src + srcParts ) ? void (0) : __assert_fail ("dst <= src || dst >= src + srcParts" , "llvm/lib/Support/APInt.cpp", 2490, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2491 | assert(dstParts <= srcParts + 1)(static_cast <bool> (dstParts <= srcParts + 1) ? void (0) : __assert_fail ("dstParts <= srcParts + 1", "llvm/lib/Support/APInt.cpp" , 2491, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2492 | |||||||||
2493 | // N loops; minimum of dstParts and srcParts. | ||||||||
2494 | unsigned n = std::min(dstParts, srcParts); | ||||||||
2495 | |||||||||
2496 | for (unsigned i = 0; i < n; i++) { | ||||||||
2497 | // [LOW, HIGH] = MULTIPLIER * SRC[i] + DST[i] + CARRY. | ||||||||
2498 | // This cannot overflow, because: | ||||||||
2499 | // (n - 1) * (n - 1) + 2 (n - 1) = (n - 1) * (n + 1) | ||||||||
2500 | // which is less than n^2. | ||||||||
2501 | WordType srcPart = src[i]; | ||||||||
2502 | WordType low, mid, high; | ||||||||
2503 | if (multiplier == 0 || srcPart == 0) { | ||||||||
2504 | low = carry; | ||||||||
2505 | high = 0; | ||||||||
2506 | } else { | ||||||||
2507 | low = lowHalf(srcPart) * lowHalf(multiplier); | ||||||||
2508 | high = highHalf(srcPart) * highHalf(multiplier); | ||||||||
2509 | |||||||||
2510 | mid = lowHalf(srcPart) * highHalf(multiplier); | ||||||||
2511 | high += highHalf(mid); | ||||||||
2512 | mid <<= APINT_BITS_PER_WORD / 2; | ||||||||
2513 | if (low + mid < low) | ||||||||
2514 | high++; | ||||||||
2515 | low += mid; | ||||||||
2516 | |||||||||
2517 | mid = highHalf(srcPart) * lowHalf(multiplier); | ||||||||
2518 | high += highHalf(mid); | ||||||||
2519 | mid <<= APINT_BITS_PER_WORD / 2; | ||||||||
2520 | if (low + mid < low) | ||||||||
2521 | high++; | ||||||||
2522 | low += mid; | ||||||||
2523 | |||||||||
2524 | // Now add carry. | ||||||||
2525 | if (low + carry < low) | ||||||||
2526 | high++; | ||||||||
2527 | low += carry; | ||||||||
2528 | } | ||||||||
2529 | |||||||||
2530 | if (add) { | ||||||||
2531 | // And now DST[i], and store the new low part there. | ||||||||
2532 | if (low + dst[i] < low) | ||||||||
2533 | high++; | ||||||||
2534 | dst[i] += low; | ||||||||
2535 | } else | ||||||||
2536 | dst[i] = low; | ||||||||
2537 | |||||||||
2538 | carry = high; | ||||||||
2539 | } | ||||||||
2540 | |||||||||
2541 | if (srcParts < dstParts) { | ||||||||
2542 | // Full multiplication, there is no overflow. | ||||||||
2543 | assert(srcParts + 1 == dstParts)(static_cast <bool> (srcParts + 1 == dstParts) ? void ( 0) : __assert_fail ("srcParts + 1 == dstParts", "llvm/lib/Support/APInt.cpp" , 2543, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2544 | dst[srcParts] = carry; | ||||||||
2545 | return 0; | ||||||||
2546 | } | ||||||||
2547 | |||||||||
2548 | // We overflowed if there is carry. | ||||||||
2549 | if (carry) | ||||||||
2550 | return 1; | ||||||||
2551 | |||||||||
2552 | // We would overflow if any significant unwritten parts would be | ||||||||
2553 | // non-zero. This is true if any remaining src parts are non-zero | ||||||||
2554 | // and the multiplier is non-zero. | ||||||||
2555 | if (multiplier) | ||||||||
2556 | for (unsigned i = dstParts; i < srcParts; i++) | ||||||||
2557 | if (src[i]) | ||||||||
2558 | return 1; | ||||||||
2559 | |||||||||
2560 | // We fitted in the narrow destination. | ||||||||
2561 | return 0; | ||||||||
2562 | } | ||||||||
2563 | |||||||||
2564 | /// DST = LHS * RHS, where DST has the same width as the operands and | ||||||||
2565 | /// is filled with the least significant parts of the result. Returns | ||||||||
2566 | /// one if overflow occurred, otherwise zero. DST must be disjoint | ||||||||
2567 | /// from both operands. | ||||||||
2568 | int APInt::tcMultiply(WordType *dst, const WordType *lhs, | ||||||||
2569 | const WordType *rhs, unsigned parts) { | ||||||||
2570 | assert(dst != lhs && dst != rhs)(static_cast <bool> (dst != lhs && dst != rhs) ? void (0) : __assert_fail ("dst != lhs && dst != rhs" , "llvm/lib/Support/APInt.cpp", 2570, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2571 | |||||||||
2572 | int overflow = 0; | ||||||||
2573 | tcSet(dst, 0, parts); | ||||||||
2574 | |||||||||
2575 | for (unsigned i = 0; i < parts; i++) | ||||||||
2576 | overflow |= tcMultiplyPart(&dst[i], lhs, rhs[i], 0, parts, | ||||||||
2577 | parts - i, true); | ||||||||
2578 | |||||||||
2579 | return overflow; | ||||||||
2580 | } | ||||||||
2581 | |||||||||
2582 | /// DST = LHS * RHS, where DST has width the sum of the widths of the | ||||||||
2583 | /// operands. No overflow occurs. DST must be disjoint from both operands. | ||||||||
2584 | void APInt::tcFullMultiply(WordType *dst, const WordType *lhs, | ||||||||
2585 | const WordType *rhs, unsigned lhsParts, | ||||||||
2586 | unsigned rhsParts) { | ||||||||
2587 | // Put the narrower number on the LHS for less loops below. | ||||||||
2588 | if (lhsParts > rhsParts) | ||||||||
2589 | return tcFullMultiply (dst, rhs, lhs, rhsParts, lhsParts); | ||||||||
2590 | |||||||||
2591 | assert(dst != lhs && dst != rhs)(static_cast <bool> (dst != lhs && dst != rhs) ? void (0) : __assert_fail ("dst != lhs && dst != rhs" , "llvm/lib/Support/APInt.cpp", 2591, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2592 | |||||||||
2593 | tcSet(dst, 0, rhsParts); | ||||||||
2594 | |||||||||
2595 | for (unsigned i = 0; i < lhsParts; i++) | ||||||||
2596 | tcMultiplyPart(&dst[i], rhs, lhs[i], 0, rhsParts, rhsParts + 1, true); | ||||||||
2597 | } | ||||||||
2598 | |||||||||
2599 | // If RHS is zero LHS and REMAINDER are left unchanged, return one. | ||||||||
2600 | // Otherwise set LHS to LHS / RHS with the fractional part discarded, | ||||||||
2601 | // set REMAINDER to the remainder, return zero. i.e. | ||||||||
2602 | // | ||||||||
2603 | // OLD_LHS = RHS * LHS + REMAINDER | ||||||||
2604 | // | ||||||||
2605 | // SCRATCH is a bignum of the same size as the operands and result for | ||||||||
2606 | // use by the routine; its contents need not be initialized and are | ||||||||
2607 | // destroyed. LHS, REMAINDER and SCRATCH must be distinct. | ||||||||
2608 | int APInt::tcDivide(WordType *lhs, const WordType *rhs, | ||||||||
2609 | WordType *remainder, WordType *srhs, | ||||||||
2610 | unsigned parts) { | ||||||||
2611 | assert(lhs != remainder && lhs != srhs && remainder != srhs)(static_cast <bool> (lhs != remainder && lhs != srhs && remainder != srhs) ? void (0) : __assert_fail ("lhs != remainder && lhs != srhs && remainder != srhs" , "llvm/lib/Support/APInt.cpp", 2611, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2612 | |||||||||
2613 | unsigned shiftCount = tcMSB(rhs, parts) + 1; | ||||||||
2614 | if (shiftCount == 0) | ||||||||
2615 | return true; | ||||||||
2616 | |||||||||
2617 | shiftCount = parts * APINT_BITS_PER_WORD - shiftCount; | ||||||||
2618 | unsigned n = shiftCount / APINT_BITS_PER_WORD; | ||||||||
2619 | WordType mask = (WordType) 1 << (shiftCount % APINT_BITS_PER_WORD); | ||||||||
2620 | |||||||||
2621 | tcAssign(srhs, rhs, parts); | ||||||||
2622 | tcShiftLeft(srhs, parts, shiftCount); | ||||||||
2623 | tcAssign(remainder, lhs, parts); | ||||||||
2624 | tcSet(lhs, 0, parts); | ||||||||
2625 | |||||||||
2626 | // Loop, subtracting SRHS if REMAINDER is greater and adding that to the | ||||||||
2627 | // total. | ||||||||
2628 | for (;;) { | ||||||||
2629 | int compare = tcCompare(remainder, srhs, parts); | ||||||||
2630 | if (compare >= 0) { | ||||||||
2631 | tcSubtract(remainder, srhs, 0, parts); | ||||||||
2632 | lhs[n] |= mask; | ||||||||
2633 | } | ||||||||
2634 | |||||||||
2635 | if (shiftCount == 0) | ||||||||
2636 | break; | ||||||||
2637 | shiftCount--; | ||||||||
2638 | tcShiftRight(srhs, parts, 1); | ||||||||
2639 | if ((mask >>= 1) == 0) { | ||||||||
2640 | mask = (WordType) 1 << (APINT_BITS_PER_WORD - 1); | ||||||||
2641 | n--; | ||||||||
2642 | } | ||||||||
2643 | } | ||||||||
2644 | |||||||||
2645 | return false; | ||||||||
2646 | } | ||||||||
2647 | |||||||||
2648 | /// Shift a bignum left Cound bits in-place. Shifted in bits are zero. There are | ||||||||
2649 | /// no restrictions on Count. | ||||||||
2650 | void APInt::tcShiftLeft(WordType *Dst, unsigned Words, unsigned Count) { | ||||||||
2651 | // Don't bother performing a no-op shift. | ||||||||
2652 | if (!Count) | ||||||||
2653 | return; | ||||||||
2654 | |||||||||
2655 | // WordShift is the inter-part shift; BitShift is the intra-part shift. | ||||||||
2656 | unsigned WordShift = std::min(Count / APINT_BITS_PER_WORD, Words); | ||||||||
2657 | unsigned BitShift = Count % APINT_BITS_PER_WORD; | ||||||||
2658 | |||||||||
2659 | // Fastpath for moving by whole words. | ||||||||
2660 | if (BitShift == 0) { | ||||||||
2661 | std::memmove(Dst + WordShift, Dst, (Words - WordShift) * APINT_WORD_SIZE); | ||||||||
2662 | } else { | ||||||||
2663 | while (Words-- > WordShift) { | ||||||||
2664 | Dst[Words] = Dst[Words - WordShift] << BitShift; | ||||||||
2665 | if (Words > WordShift) | ||||||||
2666 | Dst[Words] |= | ||||||||
2667 | Dst[Words - WordShift - 1] >> (APINT_BITS_PER_WORD - BitShift); | ||||||||
2668 | } | ||||||||
2669 | } | ||||||||
2670 | |||||||||
2671 | // Fill in the remainder with 0s. | ||||||||
2672 | std::memset(Dst, 0, WordShift * APINT_WORD_SIZE); | ||||||||
2673 | } | ||||||||
2674 | |||||||||
2675 | /// Shift a bignum right Count bits in-place. Shifted in bits are zero. There | ||||||||
2676 | /// are no restrictions on Count. | ||||||||
2677 | void APInt::tcShiftRight(WordType *Dst, unsigned Words, unsigned Count) { | ||||||||
2678 | // Don't bother performing a no-op shift. | ||||||||
2679 | if (!Count) | ||||||||
2680 | return; | ||||||||
2681 | |||||||||
2682 | // WordShift is the inter-part shift; BitShift is the intra-part shift. | ||||||||
2683 | unsigned WordShift = std::min(Count / APINT_BITS_PER_WORD, Words); | ||||||||
2684 | unsigned BitShift = Count % APINT_BITS_PER_WORD; | ||||||||
2685 | |||||||||
2686 | unsigned WordsToMove = Words - WordShift; | ||||||||
2687 | // Fastpath for moving by whole words. | ||||||||
2688 | if (BitShift == 0) { | ||||||||
2689 | std::memmove(Dst, Dst + WordShift, WordsToMove * APINT_WORD_SIZE); | ||||||||
2690 | } else { | ||||||||
2691 | for (unsigned i = 0; i != WordsToMove; ++i) { | ||||||||
2692 | Dst[i] = Dst[i + WordShift] >> BitShift; | ||||||||
2693 | if (i + 1 != WordsToMove) | ||||||||
2694 | Dst[i] |= Dst[i + WordShift + 1] << (APINT_BITS_PER_WORD - BitShift); | ||||||||
2695 | } | ||||||||
2696 | } | ||||||||
2697 | |||||||||
2698 | // Fill in the remainder with 0s. | ||||||||
2699 | std::memset(Dst + WordsToMove, 0, WordShift * APINT_WORD_SIZE); | ||||||||
2700 | } | ||||||||
2701 | |||||||||
2702 | // Comparison (unsigned) of two bignums. | ||||||||
2703 | int APInt::tcCompare(const WordType *lhs, const WordType *rhs, | ||||||||
2704 | unsigned parts) { | ||||||||
2705 | while (parts) { | ||||||||
2706 | parts--; | ||||||||
2707 | if (lhs[parts] != rhs[parts]) | ||||||||
2708 | return (lhs[parts] > rhs[parts]) ? 1 : -1; | ||||||||
2709 | } | ||||||||
2710 | |||||||||
2711 | return 0; | ||||||||
2712 | } | ||||||||
2713 | |||||||||
2714 | APInt llvm::APIntOps::RoundingUDiv(const APInt &A, const APInt &B, | ||||||||
2715 | APInt::Rounding RM) { | ||||||||
2716 | // Currently udivrem always rounds down. | ||||||||
2717 | switch (RM) { | ||||||||
2718 | case APInt::Rounding::DOWN: | ||||||||
2719 | case APInt::Rounding::TOWARD_ZERO: | ||||||||
2720 | return A.udiv(B); | ||||||||
2721 | case APInt::Rounding::UP: { | ||||||||
2722 | APInt Quo, Rem; | ||||||||
2723 | APInt::udivrem(A, B, Quo, Rem); | ||||||||
2724 | if (Rem.isZero()) | ||||||||
2725 | return Quo; | ||||||||
2726 | return Quo + 1; | ||||||||
2727 | } | ||||||||
2728 | } | ||||||||
2729 | llvm_unreachable("Unknown APInt::Rounding enum")::llvm::llvm_unreachable_internal("Unknown APInt::Rounding enum" , "llvm/lib/Support/APInt.cpp", 2729); | ||||||||
2730 | } | ||||||||
2731 | |||||||||
2732 | APInt llvm::APIntOps::RoundingSDiv(const APInt &A, const APInt &B, | ||||||||
2733 | APInt::Rounding RM) { | ||||||||
2734 | switch (RM) { | ||||||||
2735 | case APInt::Rounding::DOWN: | ||||||||
2736 | case APInt::Rounding::UP: { | ||||||||
2737 | APInt Quo, Rem; | ||||||||
2738 | APInt::sdivrem(A, B, Quo, Rem); | ||||||||
2739 | if (Rem.isZero()) | ||||||||
2740 | return Quo; | ||||||||
2741 | // This algorithm deals with arbitrary rounding mode used by sdivrem. | ||||||||
2742 | // We want to check whether the non-integer part of the mathematical value | ||||||||
2743 | // is negative or not. If the non-integer part is negative, we need to round | ||||||||
2744 | // down from Quo; otherwise, if it's positive or 0, we return Quo, as it's | ||||||||
2745 | // already rounded down. | ||||||||
2746 | if (RM == APInt::Rounding::DOWN) { | ||||||||
2747 | if (Rem.isNegative() != B.isNegative()) | ||||||||
2748 | return Quo - 1; | ||||||||
2749 | return Quo; | ||||||||
2750 | } | ||||||||
2751 | if (Rem.isNegative() != B.isNegative()) | ||||||||
2752 | return Quo; | ||||||||
2753 | return Quo + 1; | ||||||||
2754 | } | ||||||||
2755 | // Currently sdiv rounds towards zero. | ||||||||
2756 | case APInt::Rounding::TOWARD_ZERO: | ||||||||
2757 | return A.sdiv(B); | ||||||||
2758 | } | ||||||||
2759 | llvm_unreachable("Unknown APInt::Rounding enum")::llvm::llvm_unreachable_internal("Unknown APInt::Rounding enum" , "llvm/lib/Support/APInt.cpp", 2759); | ||||||||
2760 | } | ||||||||
2761 | |||||||||
2762 | std::optional<APInt> | ||||||||
2763 | llvm::APIntOps::SolveQuadraticEquationWrap(APInt A, APInt B, APInt C, | ||||||||
2764 | unsigned RangeWidth) { | ||||||||
2765 | unsigned CoeffWidth = A.getBitWidth(); | ||||||||
2766 | assert(CoeffWidth == B.getBitWidth() && CoeffWidth == C.getBitWidth())(static_cast <bool> (CoeffWidth == B.getBitWidth() && CoeffWidth == C.getBitWidth()) ? void (0) : __assert_fail ("CoeffWidth == B.getBitWidth() && CoeffWidth == C.getBitWidth()" , "llvm/lib/Support/APInt.cpp", 2766, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2767 | assert(RangeWidth <= CoeffWidth &&(static_cast <bool> (RangeWidth <= CoeffWidth && "Value range width should be less than coefficient width") ? void (0) : __assert_fail ("RangeWidth <= CoeffWidth && \"Value range width should be less than coefficient width\"" , "llvm/lib/Support/APInt.cpp", 2768, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2768 | "Value range width should be less than coefficient width")(static_cast <bool> (RangeWidth <= CoeffWidth && "Value range width should be less than coefficient width") ? void (0) : __assert_fail ("RangeWidth <= CoeffWidth && \"Value range width should be less than coefficient width\"" , "llvm/lib/Support/APInt.cpp", 2768, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2769 | assert(RangeWidth > 1 && "Value range bit width should be > 1")(static_cast <bool> (RangeWidth > 1 && "Value range bit width should be > 1" ) ? void (0) : __assert_fail ("RangeWidth > 1 && \"Value range bit width should be > 1\"" , "llvm/lib/Support/APInt.cpp", 2769, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2770 | |||||||||
2771 | LLVM_DEBUG(dbgs() << __func__ << ": solving " << A << "x^2 + " << Bdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": solving " << A << "x^2 + " << B << "x + " << C << ", rw:" << RangeWidth << '\n'; } } while (false) | ||||||||
2772 | << "x + " << C << ", rw:" << RangeWidth << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": solving " << A << "x^2 + " << B << "x + " << C << ", rw:" << RangeWidth << '\n'; } } while (false); | ||||||||
2773 | |||||||||
2774 | // Identify 0 as a (non)solution immediately. | ||||||||
2775 | if (C.sextOrTrunc(RangeWidth).isZero()) { | ||||||||
2776 | LLVM_DEBUG(dbgs() << __func__ << ": zero solution\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": zero solution\n" ; } } while (false); | ||||||||
2777 | return APInt(CoeffWidth, 0); | ||||||||
2778 | } | ||||||||
2779 | |||||||||
2780 | // The result of APInt arithmetic has the same bit width as the operands, | ||||||||
2781 | // so it can actually lose high bits. A product of two n-bit integers needs | ||||||||
2782 | // 2n-1 bits to represent the full value. | ||||||||
2783 | // The operation done below (on quadratic coefficients) that can produce | ||||||||
2784 | // the largest value is the evaluation of the equation during bisection, | ||||||||
2785 | // which needs 3 times the bitwidth of the coefficient, so the total number | ||||||||
2786 | // of required bits is 3n. | ||||||||
2787 | // | ||||||||
2788 | // The purpose of this extension is to simulate the set Z of all integers, | ||||||||
2789 | // where n+1 > n for all n in Z. In Z it makes sense to talk about positive | ||||||||
2790 | // and negative numbers (not so much in a modulo arithmetic). The method | ||||||||
2791 | // used to solve the equation is based on the standard formula for real | ||||||||
2792 | // numbers, and uses the concepts of "positive" and "negative" with their | ||||||||
2793 | // usual meanings. | ||||||||
2794 | CoeffWidth *= 3; | ||||||||
2795 | A = A.sext(CoeffWidth); | ||||||||
2796 | B = B.sext(CoeffWidth); | ||||||||
2797 | C = C.sext(CoeffWidth); | ||||||||
2798 | |||||||||
2799 | // Make A > 0 for simplicity. Negate cannot overflow at this point because | ||||||||
2800 | // the bit width has increased. | ||||||||
2801 | if (A.isNegative()) { | ||||||||
2802 | A.negate(); | ||||||||
2803 | B.negate(); | ||||||||
2804 | C.negate(); | ||||||||
2805 | } | ||||||||
2806 | |||||||||
2807 | // Solving an equation q(x) = 0 with coefficients in modular arithmetic | ||||||||
2808 | // is really solving a set of equations q(x) = kR for k = 0, 1, 2, ..., | ||||||||
2809 | // and R = 2^BitWidth. | ||||||||
2810 | // Since we're trying not only to find exact solutions, but also values | ||||||||
2811 | // that "wrap around", such a set will always have a solution, i.e. an x | ||||||||
2812 | // that satisfies at least one of the equations, or such that |q(x)| | ||||||||
2813 | // exceeds kR, while |q(x-1)| for the same k does not. | ||||||||
2814 | // | ||||||||
2815 | // We need to find a value k, such that Ax^2 + Bx + C = kR will have a | ||||||||
2816 | // positive solution n (in the above sense), and also such that the n | ||||||||
2817 | // will be the least among all solutions corresponding to k = 0, 1, ... | ||||||||
2818 | // (more precisely, the least element in the set | ||||||||
2819 | // { n(k) | k is such that a solution n(k) exists }). | ||||||||
2820 | // | ||||||||
2821 | // Consider the parabola (over real numbers) that corresponds to the | ||||||||
2822 | // quadratic equation. Since A > 0, the arms of the parabola will point | ||||||||
2823 | // up. Picking different values of k will shift it up and down by R. | ||||||||
2824 | // | ||||||||
2825 | // We want to shift the parabola in such a way as to reduce the problem | ||||||||
2826 | // of solving q(x) = kR to solving shifted_q(x) = 0. | ||||||||
2827 | // (The interesting solutions are the ceilings of the real number | ||||||||
2828 | // solutions.) | ||||||||
2829 | APInt R = APInt::getOneBitSet(CoeffWidth, RangeWidth); | ||||||||
2830 | APInt TwoA = 2 * A; | ||||||||
2831 | APInt SqrB = B * B; | ||||||||
2832 | bool PickLow; | ||||||||
2833 | |||||||||
2834 | auto RoundUp = [] (const APInt &V, const APInt &A) -> APInt { | ||||||||
2835 | assert(A.isStrictlyPositive())(static_cast <bool> (A.isStrictlyPositive()) ? void (0) : __assert_fail ("A.isStrictlyPositive()", "llvm/lib/Support/APInt.cpp" , 2835, __extension__ __PRETTY_FUNCTION__)); | ||||||||
2836 | APInt T = V.abs().urem(A); | ||||||||
2837 | if (T.isZero()) | ||||||||
2838 | return V; | ||||||||
2839 | return V.isNegative() ? V+T : V+(A-T); | ||||||||
2840 | }; | ||||||||
2841 | |||||||||
2842 | // The vertex of the parabola is at -B/2A, but since A > 0, it's negative | ||||||||
2843 | // iff B is positive. | ||||||||
2844 | if (B.isNonNegative()) { | ||||||||
2845 | // If B >= 0, the vertex it at a negative location (or at 0), so in | ||||||||
2846 | // order to have a non-negative solution we need to pick k that makes | ||||||||
2847 | // C-kR negative. To satisfy all the requirements for the solution | ||||||||
2848 | // that we are looking for, it needs to be closest to 0 of all k. | ||||||||
2849 | C = C.srem(R); | ||||||||
2850 | if (C.isStrictlyPositive()) | ||||||||
2851 | C -= R; | ||||||||
2852 | // Pick the greater solution. | ||||||||
2853 | PickLow = false; | ||||||||
2854 | } else { | ||||||||
2855 | // If B < 0, the vertex is at a positive location. For any solution | ||||||||
2856 | // to exist, the discriminant must be non-negative. This means that | ||||||||
2857 | // C-kR <= B^2/4A is a necessary condition for k, i.e. there is a | ||||||||
2858 | // lower bound on values of k: kR >= C - B^2/4A. | ||||||||
2859 | APInt LowkR = C - SqrB.udiv(2*TwoA); // udiv because all values > 0. | ||||||||
2860 | // Round LowkR up (towards +inf) to the nearest kR. | ||||||||
2861 | LowkR = RoundUp(LowkR, R); | ||||||||
2862 | |||||||||
2863 | // If there exists k meeting the condition above, and such that | ||||||||
2864 | // C-kR > 0, there will be two positive real number solutions of | ||||||||
2865 | // q(x) = kR. Out of all such values of k, pick the one that makes | ||||||||
2866 | // C-kR closest to 0, (i.e. pick maximum k such that C-kR > 0). | ||||||||
2867 | // In other words, find maximum k such that LowkR <= kR < C. | ||||||||
2868 | if (C.sgt(LowkR)) { | ||||||||
2869 | // If LowkR < C, then such a k is guaranteed to exist because | ||||||||
2870 | // LowkR itself is a multiple of R. | ||||||||
2871 | C -= -RoundUp(-C, R); // C = C - RoundDown(C, R) | ||||||||
2872 | // Pick the smaller solution. | ||||||||
2873 | PickLow = true; | ||||||||
2874 | } else { | ||||||||
2875 | // If C-kR < 0 for all potential k's, it means that one solution | ||||||||
2876 | // will be negative, while the other will be positive. The positive | ||||||||
2877 | // solution will shift towards 0 if the parabola is moved up. | ||||||||
2878 | // Pick the kR closest to the lower bound (i.e. make C-kR closest | ||||||||
2879 | // to 0, or in other words, out of all parabolas that have solutions, | ||||||||
2880 | // pick the one that is the farthest "up"). | ||||||||
2881 | // Since LowkR is itself a multiple of R, simply take C-LowkR. | ||||||||
2882 | C -= LowkR; | ||||||||
2883 | // Pick the greater solution. | ||||||||
2884 | PickLow = false; | ||||||||
2885 | } | ||||||||
2886 | } | ||||||||
2887 | |||||||||
2888 | LLVM_DEBUG(dbgs() << __func__ << ": updated coefficients " << A << "x^2 + "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": updated coefficients " << A << "x^2 + " << B << "x + " << C << ", rw:" << RangeWidth << '\n'; } } while (false) | ||||||||
2889 | << B << "x + " << C << ", rw:" << RangeWidth << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": updated coefficients " << A << "x^2 + " << B << "x + " << C << ", rw:" << RangeWidth << '\n'; } } while (false); | ||||||||
2890 | |||||||||
2891 | APInt D = SqrB - 4*A*C; | ||||||||
2892 | assert(D.isNonNegative() && "Negative discriminant")(static_cast <bool> (D.isNonNegative() && "Negative discriminant" ) ? void (0) : __assert_fail ("D.isNonNegative() && \"Negative discriminant\"" , "llvm/lib/Support/APInt.cpp", 2892, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2893 | APInt SQ = D.sqrt(); | ||||||||
2894 | |||||||||
2895 | APInt Q = SQ * SQ; | ||||||||
2896 | bool InexactSQ = Q != D; | ||||||||
2897 | // The calculated SQ may actually be greater than the exact (non-integer) | ||||||||
2898 | // value. If that's the case, decrement SQ to get a value that is lower. | ||||||||
2899 | if (Q.sgt(D)) | ||||||||
2900 | SQ -= 1; | ||||||||
2901 | |||||||||
2902 | APInt X; | ||||||||
2903 | APInt Rem; | ||||||||
2904 | |||||||||
2905 | // SQ is rounded down (i.e SQ * SQ <= D), so the roots may be inexact. | ||||||||
2906 | // When using the quadratic formula directly, the calculated low root | ||||||||
2907 | // may be greater than the exact one, since we would be subtracting SQ. | ||||||||
2908 | // To make sure that the calculated root is not greater than the exact | ||||||||
2909 | // one, subtract SQ+1 when calculating the low root (for inexact value | ||||||||
2910 | // of SQ). | ||||||||
2911 | if (PickLow) | ||||||||
2912 | APInt::sdivrem(-B - (SQ+InexactSQ), TwoA, X, Rem); | ||||||||
2913 | else | ||||||||
2914 | APInt::sdivrem(-B + SQ, TwoA, X, Rem); | ||||||||
2915 | |||||||||
2916 | // The updated coefficients should be such that the (exact) solution is | ||||||||
2917 | // positive. Since APInt division rounds towards 0, the calculated one | ||||||||
2918 | // can be 0, but cannot be negative. | ||||||||
2919 | assert(X.isNonNegative() && "Solution should be non-negative")(static_cast <bool> (X.isNonNegative() && "Solution should be non-negative" ) ? void (0) : __assert_fail ("X.isNonNegative() && \"Solution should be non-negative\"" , "llvm/lib/Support/APInt.cpp", 2919, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2920 | |||||||||
2921 | if (!InexactSQ && Rem.isZero()) { | ||||||||
2922 | LLVM_DEBUG(dbgs() << __func__ << ": solution (root): " << X << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": solution (root): " << X << '\n'; } } while (false); | ||||||||
2923 | return X; | ||||||||
2924 | } | ||||||||
2925 | |||||||||
2926 | assert((SQ*SQ).sle(D) && "SQ = |_sqrt(D)_|, so SQ*SQ <= D")(static_cast <bool> ((SQ*SQ).sle(D) && "SQ = |_sqrt(D)_|, so SQ*SQ <= D" ) ? void (0) : __assert_fail ("(SQ*SQ).sle(D) && \"SQ = |_sqrt(D)_|, so SQ*SQ <= D\"" , "llvm/lib/Support/APInt.cpp", 2926, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2927 | // The exact value of the square root of D should be between SQ and SQ+1. | ||||||||
2928 | // This implies that the solution should be between that corresponding to | ||||||||
2929 | // SQ (i.e. X) and that corresponding to SQ+1. | ||||||||
2930 | // | ||||||||
2931 | // The calculated X cannot be greater than the exact (real) solution. | ||||||||
2932 | // Actually it must be strictly less than the exact solution, while | ||||||||
2933 | // X+1 will be greater than or equal to it. | ||||||||
2934 | |||||||||
2935 | APInt VX = (A*X + B)*X + C; | ||||||||
2936 | APInt VY = VX + TwoA*X + A + B; | ||||||||
2937 | bool SignChange = | ||||||||
2938 | VX.isNegative() != VY.isNegative() || VX.isZero() != VY.isZero(); | ||||||||
2939 | // If the sign did not change between X and X+1, X is not a valid solution. | ||||||||
2940 | // This could happen when the actual (exact) roots don't have an integer | ||||||||
2941 | // between them, so they would both be contained between X and X+1. | ||||||||
2942 | if (!SignChange) { | ||||||||
2943 | LLVM_DEBUG(dbgs() << __func__ << ": no valid solution\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": no valid solution\n" ; } } while (false); | ||||||||
2944 | return std::nullopt; | ||||||||
2945 | } | ||||||||
2946 | |||||||||
2947 | X += 1; | ||||||||
2948 | LLVM_DEBUG(dbgs() << __func__ << ": solution (wrap): " << X << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("apint")) { dbgs() << __func__ << ": solution (wrap): " << X << '\n'; } } while (false); | ||||||||
2949 | return X; | ||||||||
2950 | } | ||||||||
2951 | |||||||||
2952 | std::optional<unsigned> | ||||||||
2953 | llvm::APIntOps::GetMostSignificantDifferentBit(const APInt &A, const APInt &B) { | ||||||||
2954 | assert(A.getBitWidth() == B.getBitWidth() && "Must have the same bitwidth")(static_cast <bool> (A.getBitWidth() == B.getBitWidth() && "Must have the same bitwidth") ? void (0) : __assert_fail ("A.getBitWidth() == B.getBitWidth() && \"Must have the same bitwidth\"" , "llvm/lib/Support/APInt.cpp", 2954, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2955 | if (A == B) | ||||||||
2956 | return std::nullopt; | ||||||||
2957 | return A.getBitWidth() - ((A ^ B).countl_zero() + 1); | ||||||||
2958 | } | ||||||||
2959 | |||||||||
2960 | APInt llvm::APIntOps::ScaleBitMask(const APInt &A, unsigned NewBitWidth, | ||||||||
2961 | bool MatchAllBits) { | ||||||||
2962 | unsigned OldBitWidth = A.getBitWidth(); | ||||||||
2963 | assert((((OldBitWidth % NewBitWidth) == 0) ||(static_cast <bool> ((((OldBitWidth % NewBitWidth) == 0 ) || ((NewBitWidth % OldBitWidth) == 0)) && "One size should be a multiple of the other one. " "Can't do fractional scaling.") ? void (0) : __assert_fail ( "(((OldBitWidth % NewBitWidth) == 0) || ((NewBitWidth % OldBitWidth) == 0)) && \"One size should be a multiple of the other one. \" \"Can't do fractional scaling.\"" , "llvm/lib/Support/APInt.cpp", 2966, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2964 | ((NewBitWidth % OldBitWidth) == 0)) &&(static_cast <bool> ((((OldBitWidth % NewBitWidth) == 0 ) || ((NewBitWidth % OldBitWidth) == 0)) && "One size should be a multiple of the other one. " "Can't do fractional scaling.") ? void (0) : __assert_fail ( "(((OldBitWidth % NewBitWidth) == 0) || ((NewBitWidth % OldBitWidth) == 0)) && \"One size should be a multiple of the other one. \" \"Can't do fractional scaling.\"" , "llvm/lib/Support/APInt.cpp", 2966, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2965 | "One size should be a multiple of the other one. "(static_cast <bool> ((((OldBitWidth % NewBitWidth) == 0 ) || ((NewBitWidth % OldBitWidth) == 0)) && "One size should be a multiple of the other one. " "Can't do fractional scaling.") ? void (0) : __assert_fail ( "(((OldBitWidth % NewBitWidth) == 0) || ((NewBitWidth % OldBitWidth) == 0)) && \"One size should be a multiple of the other one. \" \"Can't do fractional scaling.\"" , "llvm/lib/Support/APInt.cpp", 2966, __extension__ __PRETTY_FUNCTION__ )) | ||||||||
2966 | "Can't do fractional scaling.")(static_cast <bool> ((((OldBitWidth % NewBitWidth) == 0 ) || ((NewBitWidth % OldBitWidth) == 0)) && "One size should be a multiple of the other one. " "Can't do fractional scaling.") ? void (0) : __assert_fail ( "(((OldBitWidth % NewBitWidth) == 0) || ((NewBitWidth % OldBitWidth) == 0)) && \"One size should be a multiple of the other one. \" \"Can't do fractional scaling.\"" , "llvm/lib/Support/APInt.cpp", 2966, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
2967 | |||||||||
2968 | // Check for matching bitwidths. | ||||||||
2969 | if (OldBitWidth == NewBitWidth) | ||||||||
2970 | return A; | ||||||||
2971 | |||||||||
2972 | APInt NewA = APInt::getZero(NewBitWidth); | ||||||||
2973 | |||||||||
2974 | // Check for null input. | ||||||||
2975 | if (A.isZero()) | ||||||||
2976 | return NewA; | ||||||||
2977 | |||||||||
2978 | if (NewBitWidth > OldBitWidth) { | ||||||||
2979 | // Repeat bits. | ||||||||
2980 | unsigned Scale = NewBitWidth / OldBitWidth; | ||||||||
2981 | for (unsigned i = 0; i != OldBitWidth; ++i) | ||||||||
2982 | if (A[i]) | ||||||||
2983 | NewA.setBits(i * Scale, (i + 1) * Scale); | ||||||||
2984 | } else { | ||||||||
2985 | unsigned Scale = OldBitWidth / NewBitWidth; | ||||||||
2986 | for (unsigned i = 0; i != NewBitWidth; ++i) { | ||||||||
2987 | if (MatchAllBits) { | ||||||||
2988 | if (A.extractBits(Scale, i * Scale).isAllOnes()) | ||||||||
2989 | NewA.setBit(i); | ||||||||
2990 | } else { | ||||||||
2991 | if (!A.extractBits(Scale, i * Scale).isZero()) | ||||||||
2992 | NewA.setBit(i); | ||||||||
2993 | } | ||||||||
2994 | } | ||||||||
2995 | } | ||||||||
2996 | |||||||||
2997 | return NewA; | ||||||||
2998 | } | ||||||||
2999 | |||||||||
3000 | /// StoreIntToMemory - Fills the StoreBytes bytes of memory starting from Dst | ||||||||
3001 | /// with the integer held in IntVal. | ||||||||
3002 | void llvm::StoreIntToMemory(const APInt &IntVal, uint8_t *Dst, | ||||||||
3003 | unsigned StoreBytes) { | ||||||||
3004 | assert((IntVal.getBitWidth()+7)/8 >= StoreBytes && "Integer too small!")(static_cast <bool> ((IntVal.getBitWidth()+7)/8 >= StoreBytes && "Integer too small!") ? void (0) : __assert_fail ( "(IntVal.getBitWidth()+7)/8 >= StoreBytes && \"Integer too small!\"" , "llvm/lib/Support/APInt.cpp", 3004, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
3005 | const uint8_t *Src = (const uint8_t *)IntVal.getRawData(); | ||||||||
3006 | |||||||||
3007 | if (sys::IsLittleEndianHost) { | ||||||||
3008 | // Little-endian host - the source is ordered from LSB to MSB. Order the | ||||||||
3009 | // destination from LSB to MSB: Do a straight copy. | ||||||||
3010 | memcpy(Dst, Src, StoreBytes); | ||||||||
3011 | } else { | ||||||||
3012 | // Big-endian host - the source is an array of 64 bit words ordered from | ||||||||
3013 | // LSW to MSW. Each word is ordered from MSB to LSB. Order the destination | ||||||||
3014 | // from MSB to LSB: Reverse the word order, but not the bytes in a word. | ||||||||
3015 | while (StoreBytes > sizeof(uint64_t)) { | ||||||||
3016 | StoreBytes -= sizeof(uint64_t); | ||||||||
3017 | // May not be aligned so use memcpy. | ||||||||
3018 | memcpy(Dst + StoreBytes, Src, sizeof(uint64_t)); | ||||||||
3019 | Src += sizeof(uint64_t); | ||||||||
3020 | } | ||||||||
3021 | |||||||||
3022 | memcpy(Dst, Src + sizeof(uint64_t) - StoreBytes, StoreBytes); | ||||||||
3023 | } | ||||||||
3024 | } | ||||||||
3025 | |||||||||
3026 | /// LoadIntFromMemory - Loads the integer stored in the LoadBytes bytes starting | ||||||||
3027 | /// from Src into IntVal, which is assumed to be wide enough and to hold zero. | ||||||||
3028 | void llvm::LoadIntFromMemory(APInt &IntVal, const uint8_t *Src, | ||||||||
3029 | unsigned LoadBytes) { | ||||||||
3030 | assert((IntVal.getBitWidth()+7)/8 >= LoadBytes && "Integer too small!")(static_cast <bool> ((IntVal.getBitWidth()+7)/8 >= LoadBytes && "Integer too small!") ? void (0) : __assert_fail ( "(IntVal.getBitWidth()+7)/8 >= LoadBytes && \"Integer too small!\"" , "llvm/lib/Support/APInt.cpp", 3030, __extension__ __PRETTY_FUNCTION__ )); | ||||||||
3031 | uint8_t *Dst = reinterpret_cast<uint8_t *>( | ||||||||
3032 | const_cast<uint64_t *>(IntVal.getRawData())); | ||||||||
3033 | |||||||||
3034 | if (sys::IsLittleEndianHost) | ||||||||
3035 | // Little-endian host - the destination must be ordered from LSB to MSB. | ||||||||
3036 | // The source is ordered from LSB to MSB: Do a straight copy. | ||||||||
3037 | memcpy(Dst, Src, LoadBytes); | ||||||||
3038 | else { | ||||||||
3039 | // Big-endian - the destination is an array of 64 bit words ordered from | ||||||||
3040 | // LSW to MSW. Each word must be ordered from MSB to LSB. The source is | ||||||||
3041 | // ordered from MSB to LSB: Reverse the word order, but not the bytes in | ||||||||
3042 | // a word. | ||||||||
3043 | while (LoadBytes > sizeof(uint64_t)) { | ||||||||
3044 | LoadBytes -= sizeof(uint64_t); | ||||||||
3045 | // May not be aligned so use memcpy. | ||||||||
3046 | memcpy(Dst, Src + LoadBytes, sizeof(uint64_t)); | ||||||||
3047 | Dst += sizeof(uint64_t); | ||||||||
3048 | } | ||||||||
3049 | |||||||||
3050 | memcpy(Dst + sizeof(uint64_t) - LoadBytes, Src, LoadBytes); | ||||||||
3051 | } | ||||||||
3052 | } |
1 | //===-- llvm/ADT/bit.h - C++20 <bit> ----------------------------*- 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 the C++20 <bit> header. |
11 | /// |
12 | //===----------------------------------------------------------------------===// |
13 | |
14 | #ifndef LLVM_ADT_BIT_H |
15 | #define LLVM_ADT_BIT_H |
16 | |
17 | #include "llvm/Support/Compiler.h" |
18 | #include <cstdint> |
19 | #include <limits> |
20 | #include <type_traits> |
21 | |
22 | #if !__has_builtin(__builtin_bit_cast)1 |
23 | #include <cstring> |
24 | #endif |
25 | |
26 | #if defined(_MSC_VER) && !defined(_DEBUG1) |
27 | #include <cstdlib> // for _byteswap_{ushort,ulong,uint64} |
28 | #endif |
29 | |
30 | #ifdef _MSC_VER |
31 | // Declare these intrinsics manually rather including intrin.h. It's very |
32 | // expensive, and bit.h is popular via MathExtras.h. |
33 | // #include <intrin.h> |
34 | extern "C" { |
35 | unsigned char _BitScanForward(unsigned long *_Index, unsigned long _Mask); |
36 | unsigned char _BitScanForward64(unsigned long *_Index, unsigned __int64 _Mask); |
37 | unsigned char _BitScanReverse(unsigned long *_Index, unsigned long _Mask); |
38 | unsigned char _BitScanReverse64(unsigned long *_Index, unsigned __int64 _Mask); |
39 | } |
40 | #endif |
41 | |
42 | namespace llvm { |
43 | |
44 | // This implementation of bit_cast is different from the C++20 one in two ways: |
45 | // - It isn't constexpr because that requires compiler support. |
46 | // - It requires trivially-constructible To, to avoid UB in the implementation. |
47 | template < |
48 | typename To, typename From, |
49 | typename = std::enable_if_t<sizeof(To) == sizeof(From)>, |
50 | typename = std::enable_if_t<std::is_trivially_constructible<To>::value>, |
51 | typename = std::enable_if_t<std::is_trivially_copyable<To>::value>, |
52 | typename = std::enable_if_t<std::is_trivially_copyable<From>::value>> |
53 | [[nodiscard]] inline To bit_cast(const From &from) noexcept { |
54 | #if __has_builtin(__builtin_bit_cast)1 |
55 | return __builtin_bit_cast(To, from); |
56 | #else |
57 | To to; |
58 | std::memcpy(&to, &from, sizeof(To)); |
59 | return to; |
60 | #endif |
61 | } |
62 | |
63 | /// Reverses the bytes in the given integer value V. |
64 | template <typename T, typename = std::enable_if_t<std::is_integral_v<T>>> |
65 | [[nodiscard]] constexpr T byteswap(T V) noexcept { |
66 | if constexpr (sizeof(T) == 1) { |
67 | return V; |
68 | } else if constexpr (sizeof(T) == 2) { |
69 | uint16_t UV = V; |
70 | #if defined(_MSC_VER) && !defined(_DEBUG1) |
71 | // The DLL version of the runtime lacks these functions (bug!?), but in a |
72 | // release build they're replaced with BSWAP instructions anyway. |
73 | return _byteswap_ushort(UV); |
74 | #else |
75 | uint16_t Hi = UV << 8; |
76 | uint16_t Lo = UV >> 8; |
77 | return Hi | Lo; |
78 | #endif |
79 | } else if constexpr (sizeof(T) == 4) { |
80 | uint32_t UV = V; |
81 | #if __has_builtin(__builtin_bswap32)1 |
82 | return __builtin_bswap32(UV); |
83 | #elif defined(_MSC_VER) && !defined(_DEBUG1) |
84 | return _byteswap_ulong(UV); |
85 | #else |
86 | uint32_t Byte0 = UV & 0x000000FF; |
87 | uint32_t Byte1 = UV & 0x0000FF00; |
88 | uint32_t Byte2 = UV & 0x00FF0000; |
89 | uint32_t Byte3 = UV & 0xFF000000; |
90 | return (Byte0 << 24) | (Byte1 << 8) | (Byte2 >> 8) | (Byte3 >> 24); |
91 | #endif |
92 | } else if constexpr (sizeof(T) == 8) { |
93 | uint64_t UV = V; |
94 | #if __has_builtin(__builtin_bswap64)1 |
95 | return __builtin_bswap64(UV); |
96 | #elif defined(_MSC_VER) && !defined(_DEBUG1) |
97 | return _byteswap_uint64(UV); |
98 | #else |
99 | uint64_t Hi = llvm::byteswap<uint32_t>(UV); |
100 | uint32_t Lo = llvm::byteswap<uint32_t>(UV >> 32); |
101 | return (Hi << 32) | Lo; |
102 | #endif |
103 | } else { |
104 | static_assert(!sizeof(T *), "Don't know how to handle the given type."); |
105 | return 0; |
106 | } |
107 | } |
108 | |
109 | template <typename T, typename = std::enable_if_t<std::is_unsigned_v<T>>> |
110 | [[nodiscard]] constexpr inline bool has_single_bit(T Value) noexcept { |
111 | return (Value != 0) && ((Value & (Value - 1)) == 0); |
112 | } |
113 | |
114 | namespace detail { |
115 | template <typename T, std::size_t SizeOfT> struct TrailingZerosCounter { |
116 | static unsigned count(T Val) { |
117 | if (!Val) |
118 | return std::numeric_limits<T>::digits; |
119 | if (Val & 0x1) |
120 | return 0; |
121 | |
122 | // Bisection method. |
123 | unsigned ZeroBits = 0; |
124 | T Shift = std::numeric_limits<T>::digits >> 1; |
125 | T Mask = std::numeric_limits<T>::max() >> Shift; |
126 | while (Shift) { |
127 | if ((Val & Mask) == 0) { |
128 | Val >>= Shift; |
129 | ZeroBits |= Shift; |
130 | } |
131 | Shift >>= 1; |
132 | Mask >>= Shift; |
133 | } |
134 | return ZeroBits; |
135 | } |
136 | }; |
137 | |
138 | #if defined(__GNUC__4) || defined(_MSC_VER) |
139 | template <typename T> struct TrailingZerosCounter<T, 4> { |
140 | static unsigned count(T Val) { |
141 | if (Val == 0) |
142 | return 32; |
143 | |
144 | #if __has_builtin(__builtin_ctz)1 || defined(__GNUC__4) |
145 | return __builtin_ctz(Val); |
146 | #elif defined(_MSC_VER) |
147 | unsigned long Index; |
148 | _BitScanForward(&Index, Val); |
149 | return Index; |
150 | #endif |
151 | } |
152 | }; |
153 | |
154 | #if !defined(_MSC_VER) || defined(_M_X64) |
155 | template <typename T> struct TrailingZerosCounter<T, 8> { |
156 | static unsigned count(T Val) { |
157 | if (Val == 0) |
158 | return 64; |
159 | |
160 | #if __has_builtin(__builtin_ctzll)1 || defined(__GNUC__4) |
161 | return __builtin_ctzll(Val); |
162 | #elif defined(_MSC_VER) |
163 | unsigned long Index; |
164 | _BitScanForward64(&Index, Val); |
165 | return Index; |
166 | #endif |
167 | } |
168 | }; |
169 | #endif |
170 | #endif |
171 | } // namespace detail |
172 | |
173 | /// Count number of 0's from the least significant bit to the most |
174 | /// stopping at the first 1. |
175 | /// |
176 | /// Only unsigned integral types are allowed. |
177 | /// |
178 | /// Returns std::numeric_limits<T>::digits on an input of 0. |
179 | template <typename T> [[nodiscard]] int countr_zero(T Val) { |
180 | static_assert(std::is_unsigned_v<T>, |
181 | "Only unsigned integral types are allowed."); |
182 | return llvm::detail::TrailingZerosCounter<T, sizeof(T)>::count(Val); |
183 | } |
184 | |
185 | namespace detail { |
186 | template <typename T, std::size_t SizeOfT> struct LeadingZerosCounter { |
187 | static unsigned count(T Val) { |
188 | if (!Val) |
189 | return std::numeric_limits<T>::digits; |
190 | |
191 | // Bisection method. |
192 | unsigned ZeroBits = 0; |
193 | for (T Shift = std::numeric_limits<T>::digits >> 1; Shift; Shift >>= 1) { |
194 | T Tmp = Val >> Shift; |
195 | if (Tmp) |
196 | Val = Tmp; |
197 | else |
198 | ZeroBits |= Shift; |
199 | } |
200 | return ZeroBits; |
201 | } |
202 | }; |
203 | |
204 | #if defined(__GNUC__4) || defined(_MSC_VER) |
205 | template <typename T> struct LeadingZerosCounter<T, 4> { |
206 | static unsigned count(T Val) { |
207 | if (Val == 0) |
208 | return 32; |
209 | |
210 | #if __has_builtin(__builtin_clz)1 || defined(__GNUC__4) |
211 | return __builtin_clz(Val); |
212 | #elif defined(_MSC_VER) |
213 | unsigned long Index; |
214 | _BitScanReverse(&Index, Val); |
215 | return Index ^ 31; |
216 | #endif |
217 | } |
218 | }; |
219 | |
220 | #if !defined(_MSC_VER) || defined(_M_X64) |
221 | template <typename T> struct LeadingZerosCounter<T, 8> { |
222 | static unsigned count(T Val) { |
223 | if (Val == 0) |
224 | return 64; |
225 | |
226 | #if __has_builtin(__builtin_clzll)1 || defined(__GNUC__4) |
227 | return __builtin_clzll(Val); |
228 | #elif defined(_MSC_VER) |
229 | unsigned long Index; |
230 | _BitScanReverse64(&Index, Val); |
231 | return Index ^ 63; |
232 | #endif |
233 | } |
234 | }; |
235 | #endif |
236 | #endif |
237 | } // namespace detail |
238 | |
239 | /// Count number of 0's from the most significant bit to the least |
240 | /// stopping at the first 1. |
241 | /// |
242 | /// Only unsigned integral types are allowed. |
243 | /// |
244 | /// Returns std::numeric_limits<T>::digits on an input of 0. |
245 | template <typename T> [[nodiscard]] int countl_zero(T Val) { |
246 | static_assert(std::is_unsigned_v<T>, |
247 | "Only unsigned integral types are allowed."); |
248 | return llvm::detail::LeadingZerosCounter<T, sizeof(T)>::count(Val); |
249 | } |
250 | |
251 | /// Count the number of ones from the most significant bit to the first |
252 | /// zero bit. |
253 | /// |
254 | /// Ex. countl_one(0xFF0FFF00) == 8. |
255 | /// Only unsigned integral types are allowed. |
256 | /// |
257 | /// Returns std::numeric_limits<T>::digits on an input of all ones. |
258 | template <typename T> [[nodiscard]] int countl_one(T Value) { |
259 | static_assert(std::is_unsigned_v<T>, |
260 | "Only unsigned integral types are allowed."); |
261 | return llvm::countl_zero<T>(~Value); |
262 | } |
263 | |
264 | /// Count the number of ones from the least significant bit to the first |
265 | /// zero bit. |
266 | /// |
267 | /// Ex. countr_one(0x00FF00FF) == 8. |
268 | /// Only unsigned integral types are allowed. |
269 | /// |
270 | /// Returns std::numeric_limits<T>::digits on an input of all ones. |
271 | template <typename T> [[nodiscard]] int countr_one(T Value) { |
272 | static_assert(std::is_unsigned_v<T>, |
273 | "Only unsigned integral types are allowed."); |
274 | return llvm::countr_zero<T>(~Value); |
275 | } |
276 | |
277 | /// Returns the number of bits needed to represent Value if Value is nonzero. |
278 | /// Returns 0 otherwise. |
279 | /// |
280 | /// Ex. bit_width(5) == 3. |
281 | template <typename T> [[nodiscard]] int bit_width(T Value) { |
282 | static_assert(std::is_unsigned_v<T>, |
283 | "Only unsigned integral types are allowed."); |
284 | return std::numeric_limits<T>::digits - llvm::countl_zero(Value); |
285 | } |
286 | |
287 | /// Returns the largest integral power of two no greater than Value if Value is |
288 | /// nonzero. Returns 0 otherwise. |
289 | /// |
290 | /// Ex. bit_floor(5) == 4. |
291 | template <typename T> [[nodiscard]] T bit_floor(T Value) { |
292 | static_assert(std::is_unsigned_v<T>, |
293 | "Only unsigned integral types are allowed."); |
294 | if (!Value) |
295 | return 0; |
296 | return T(1) << (llvm::bit_width(Value) - 1); |
297 | } |
298 | |
299 | /// Returns the smallest integral power of two no smaller than Value if Value is |
300 | /// nonzero. Returns 1 otherwise. |
301 | /// |
302 | /// Ex. bit_ceil(5) == 8. |
303 | /// |
304 | /// The return value is undefined if the input is larger than the largest power |
305 | /// of two representable in T. |
306 | template <typename T> [[nodiscard]] T bit_ceil(T Value) { |
307 | static_assert(std::is_unsigned_v<T>, |
308 | "Only unsigned integral types are allowed."); |
309 | if (Value < 2) |
310 | return 1; |
311 | return T(1) << llvm::bit_width<T>(Value - 1u); |
312 | } |
313 | |
314 | namespace detail { |
315 | template <typename T, std::size_t SizeOfT> struct PopulationCounter { |
316 | static int count(T Value) { |
317 | // Generic version, forward to 32 bits. |
318 | static_assert(SizeOfT <= 4, "Not implemented!"); |
319 | #if defined(__GNUC__4) |
320 | return (int)__builtin_popcount(Value); |
321 | #else |
322 | uint32_t v = Value; |
323 | v = v - ((v >> 1) & 0x55555555); |
324 | v = (v & 0x33333333) + ((v >> 2) & 0x33333333); |
325 | return int(((v + (v >> 4) & 0xF0F0F0F) * 0x1010101) >> 24); |
326 | #endif |
327 | } |
328 | }; |
329 | |
330 | template <typename T> struct PopulationCounter<T, 8> { |
331 | static int count(T Value) { |
332 | #if defined(__GNUC__4) |
333 | return (int)__builtin_popcountll(Value); |
334 | #else |
335 | uint64_t v = Value; |
336 | v = v - ((v >> 1) & 0x5555555555555555ULL); |
337 | v = (v & 0x3333333333333333ULL) + ((v >> 2) & 0x3333333333333333ULL); |
338 | v = (v + (v >> 4)) & 0x0F0F0F0F0F0F0F0FULL; |
339 | return int((uint64_t)(v * 0x0101010101010101ULL) >> 56); |
340 | #endif |
341 | } |
342 | }; |
343 | } // namespace detail |
344 | |
345 | /// Count the number of set bits in a value. |
346 | /// Ex. popcount(0xF000F000) = 8 |
347 | /// Returns 0 if the word is zero. |
348 | template <typename T, typename = std::enable_if_t<std::is_unsigned_v<T>>> |
349 | [[nodiscard]] inline int popcount(T Value) noexcept { |
350 | return detail::PopulationCounter<T, sizeof(T)>::count(Value); |
351 | } |
352 | |
353 | // Forward-declare rotr so that rotl can use it. |
354 | template <typename T, typename = std::enable_if_t<std::is_unsigned_v<T>>> |
355 | [[nodiscard]] constexpr T rotr(T V, int R); |
356 | |
357 | template <typename T, typename = std::enable_if_t<std::is_unsigned_v<T>>> |
358 | [[nodiscard]] constexpr T rotl(T V, int R) { |
359 | unsigned N = std::numeric_limits<T>::digits; |
360 | |
361 | R = R % N; |
362 | if (!R) |
363 | return V; |
364 | |
365 | if (R < 0) |
366 | return llvm::rotr(V, -R); |
367 | |
368 | return (V << R) | (V >> (N - R)); |
369 | } |
370 | |
371 | template <typename T, typename> [[nodiscard]] constexpr T rotr(T V, int R) { |
372 | unsigned N = std::numeric_limits<T>::digits; |
373 | |
374 | R = R % N; |
375 | if (!R) |
376 | return V; |
377 | |
378 | if (R < 0) |
379 | return llvm::rotl(V, -R); |
380 | |
381 | return (V >> R) | (V << (N - R)); |
382 | } |
383 | |
384 | } // namespace llvm |
385 | |
386 | #endif |