//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Sheng Zhou and is distributed under the
-// University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
-// This file implements a class to represent arbitrary precision integral
-// constant values.
+// This file implements a class to represent arbitrary precision integer
+// constant values and provide a variety of arithmetic operations on them.
//
//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "apint"
#include "llvm/ADT/APInt.h"
-
-#if 0
-#include "llvm/DerivedTypes.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/FoldingSet.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cmath>
+#include <limits>
#include <cstring>
#include <cstdlib>
using namespace llvm;
-/// mul_1 - This function performs the multiplication operation on a
-/// large integer (represented as an integer array) and a uint64_t integer.
-/// @returns the carry of the multiplication.
-static uint64_t mul_1(uint64_t dest[], uint64_t x[],
- unsigned len, uint64_t y) {
- // Split y into high 32-bit part and low 32-bit part.
- uint64_t ly = y & 0xffffffffULL, hy = y >> 32;
- uint64_t carry = 0, lx, hx;
- for (unsigned i = 0; i < len; ++i) {
- lx = x[i] & 0xffffffffULL;
- hx = x[i] >> 32;
- // hasCarry - A flag to indicate if has carry.
- // hasCarry == 0, no carry
- // hasCarry == 1, has carry
- // hasCarry == 2, no carry and the calculation result == 0.
- uint8_t hasCarry = 0;
- dest[i] = carry + lx * ly;
- // Determine if the add above introduces carry.
- hasCarry = (dest[i] < carry) ? 1 : 0;
- carry = hx * ly + (dest[i] >> 32) + (hasCarry ? (1ULL << 32) : 0);
- // The upper limit of carry can be (2^32 - 1)(2^32 - 1) +
- // (2^32 - 1) + 2^32 = 2^64.
- hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
-
- carry += (lx * hy) & 0xffffffffULL;
- dest[i] = (carry << 32) | (dest[i] & 0xffffffffULL);
- carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0) +
- (carry >> 32) + ((lx * hy) >> 32) + hx * hy;
- }
-
- return carry;
+/// A utility function for allocating memory, checking for allocation failures,
+/// and ensuring the contents are zeroed.
+inline static uint64_t* getClearedMemory(unsigned numWords) {
+ uint64_t * result = new uint64_t[numWords];
+ assert(result && "APInt memory allocation fails!");
+ memset(result, 0, numWords * sizeof(uint64_t));
+ return result;
}
-/// mul - This function multiplies integer array x[] by integer array y[] and
-/// stores the result into integer array dest[].
-/// Note the array dest[]'s size should no less than xlen + ylen.
-static void mul(uint64_t dest[], uint64_t x[], unsigned xlen,
- uint64_t y[], unsigned ylen) {
- dest[xlen] = mul_1(dest, x, xlen, y[0]);
-
- for (unsigned i = 1; i < ylen; ++i) {
- uint64_t ly = y[i] & 0xffffffffULL, hy = y[i] >> 32;
- uint64_t carry = 0, lx, hx;
- for (unsigned j = 0; j < xlen; ++j) {
- lx = x[j] & 0xffffffffULL;
- hx = x[j] >> 32;
- // hasCarry - A flag to indicate if has carry.
- // hasCarry == 0, no carry
- // hasCarry == 1, has carry
- // hasCarry == 2, no carry and the calculation result == 0.
- uint8_t hasCarry = 0;
- uint64_t resul = carry + lx * ly;
- hasCarry = (resul < carry) ? 1 : 0;
- carry = (hasCarry ? (1ULL << 32) : 0) + hx * ly + (resul >> 32);
- hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
-
- carry += (lx * hy) & 0xffffffffULL;
- resul = (carry << 32) | (resul & 0xffffffffULL);
- dest[i+j] += resul;
- carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0)+
- (carry >> 32) + (dest[i+j] < resul ? 1 : 0) +
- ((lx * hy) >> 32) + hx * hy;
- }
- dest[i+xlen] = carry;
- }
+/// A utility function for allocating memory and checking for allocation
+/// failure. The content is not zeroed.
+inline static uint64_t* getMemory(unsigned numWords) {
+ uint64_t * result = new uint64_t[numWords];
+ assert(result && "APInt memory allocation fails!");
+ return result;
}
-/// add_1 - This function adds the integer array x[] by integer y and
-/// returns the carry.
-/// @returns the carry of the addition.
-static uint64_t add_1(uint64_t dest[], uint64_t x[],
- unsigned len, uint64_t y) {
- uint64_t carry = y;
-
- for (unsigned i = 0; i < len; ++i) {
- dest[i] = carry + x[i];
- carry = (dest[i] < carry) ? 1 : 0;
- }
- return carry;
-}
+/// A utility function that converts a character to a digit.
+inline static unsigned getDigit(char cdigit, uint8_t radix) {
+ unsigned r;
-/// add - This function adds the integer array x[] by integer array
-/// y[] and returns the carry.
-static uint64_t add(uint64_t dest[], uint64_t x[],
- uint64_t y[], unsigned len) {
- unsigned carry = 0;
-
- for (unsigned i = 0; i< len; ++i) {
- carry += x[i];
- dest[i] = carry + y[i];
- carry = carry < x[i] ? 1 : (dest[i] < carry ? 1 : 0);
- }
- return carry;
-}
+ if (radix == 16) {
+ r = cdigit - '0';
+ if (r <= 9)
+ return r;
-/// sub_1 - This function subtracts the integer array x[] by
-/// integer y and returns the borrow-out carry.
-static uint64_t sub_1(uint64_t x[], unsigned len, uint64_t y) {
- uint64_t cy = y;
+ r = cdigit - 'A';
+ if (r <= 5)
+ return r + 10;
- for (unsigned i = 0; i < len; ++i) {
- uint64_t X = x[i];
- x[i] -= cy;
- if (cy > X)
- cy = 1;
- else {
- cy = 0;
- break;
- }
+ r = cdigit - 'a';
+ if (r <= 5)
+ return r + 10;
}
- return cy;
+ r = cdigit - '0';
+ if (r < radix)
+ return r;
+
+ return -1U;
}
-/// sub - This function subtracts the integer array x[] by
-/// integer array y[], and returns the borrow-out carry.
-static uint64_t sub(uint64_t dest[], uint64_t x[],
- uint64_t y[], unsigned len) {
- // Carry indicator.
- uint64_t cy = 0;
-
- for (unsigned i = 0; i < len; ++i) {
- uint64_t Y = y[i], X = x[i];
- Y += cy;
- cy = Y < cy ? 1 : 0;
- Y = X - Y;
- cy += Y > X ? 1 : 0;
- dest[i] = Y;
- }
- return cy;
+void APInt::initSlowCase(unsigned numBits, uint64_t val, bool isSigned) {
+ pVal = getClearedMemory(getNumWords());
+ pVal[0] = val;
+ if (isSigned && int64_t(val) < 0)
+ for (unsigned i = 1; i < getNumWords(); ++i)
+ pVal[i] = -1ULL;
}
-/// UnitDiv - This function divides N by D,
-/// and returns (remainder << 32) | quotient.
-/// Assumes (N >> 32) < D.
-static uint64_t unitDiv(uint64_t N, unsigned D) {
- uint64_t q, r; // q: quotient, r: remainder.
- uint64_t a1 = N >> 32; // a1: high 32-bit part of N.
- uint64_t a0 = N & 0xffffffffL; // a0: low 32-bit part of N
- if (a1 < ((D - a1 - (a0 >> 31)) & 0xffffffffL)) {
- q = N / D;
- r = N % D;
- }
- else {
- // Compute c1*2^32 + c0 = a1*2^32 + a0 - 2^31*d
- uint64_t c = N - ((uint64_t) D << 31);
- // Divide (c1*2^32 + c0) by d
- q = c / D;
- r = c % D;
- // Add 2^31 to quotient
- q += 1 << 31;
- }
-
- return (r << 32) | (q & 0xFFFFFFFFl);
-}
-
-/// subMul - This function substracts x[len-1:0] * y from
-/// dest[offset+len-1:offset], and returns the most significant
-/// word of the product, minus the borrow-out from the subtraction.
-static unsigned subMul(unsigned dest[], unsigned offset,
- unsigned x[], unsigned len, unsigned y) {
- uint64_t yl = (uint64_t) y & 0xffffffffL;
- unsigned carry = 0;
- unsigned j = 0;
- do {
- uint64_t prod = ((uint64_t) x[j] & 0xffffffffL) * yl;
- unsigned prod_low = (unsigned) prod;
- unsigned prod_high = (unsigned) (prod >> 32);
- prod_low += carry;
- carry = (prod_low < carry ? 1 : 0) + prod_high;
- unsigned x_j = dest[offset+j];
- prod_low = x_j - prod_low;
- if (prod_low > x_j) ++carry;
- dest[offset+j] = prod_low;
- } while (++j < len);
- return carry;
+void APInt::initSlowCase(const APInt& that) {
+ pVal = getMemory(getNumWords());
+ memcpy(pVal, that.pVal, getNumWords() * APINT_WORD_SIZE);
}
-/// div - This is basically Knuth's formulation of the classical algorithm.
-/// Correspondance with Knuth's notation:
-/// Knuth's u[0:m+n] == zds[nx:0].
-/// Knuth's v[1:n] == y[ny-1:0]
-/// Knuth's n == ny.
-/// Knuth's m == nx-ny.
-/// Our nx == Knuth's m+n.
-/// Could be re-implemented using gmp's mpn_divrem:
-/// zds[nx] = mpn_divrem (&zds[ny], 0, zds, nx, y, ny).
-static void div(unsigned zds[], unsigned nx, unsigned y[], unsigned ny) {
- unsigned j = nx;
- do { // loop over digits of quotient
- // Knuth's j == our nx-j.
- // Knuth's u[j:j+n] == our zds[j:j-ny].
- unsigned qhat; // treated as unsigned
- if (zds[j] == y[ny-1]) qhat = -1U; // 0xffffffff
- else {
- uint64_t w = (((uint64_t)(zds[j])) << 32) +
- ((uint64_t)zds[j-1] & 0xffffffffL);
- qhat = (unsigned) unitDiv(w, y[ny-1]);
- }
- if (qhat) {
- unsigned borrow = subMul(zds, j - ny, y, ny, qhat);
- unsigned save = zds[j];
- uint64_t num = ((uint64_t)save&0xffffffffL) -
- ((uint64_t)borrow&0xffffffffL);
- while (num) {
- qhat--;
- uint64_t carry = 0;
- for (unsigned i = 0; i < ny; i++) {
- carry += ((uint64_t) zds[j-ny+i] & 0xffffffffL)
- + ((uint64_t) y[i] & 0xffffffffL);
- zds[j-ny+i] = (unsigned) carry;
- carry >>= 32;
- }
- zds[j] += carry;
- num = carry - 1;
- }
- }
- zds[j] = qhat;
- } while (--j >= ny);
-}
-
-/// lshift - This function shift x[0:len-1] left by shiftAmt bits, and
-/// store the len least significant words of the result in
-/// dest[d_offset:d_offset+len-1]. It returns the bits shifted out from
-/// the most significant digit.
-static uint64_t lshift(uint64_t dest[], unsigned d_offset,
- uint64_t x[], unsigned len, unsigned shiftAmt) {
- unsigned count = 64 - shiftAmt;
- int i = len - 1;
- uint64_t high_word = x[i], retVal = high_word >> count;
- ++d_offset;
- while (--i >= 0) {
- uint64_t low_word = x[i];
- dest[d_offset+i] = (high_word << shiftAmt) | (low_word >> count);
- high_word = low_word;
- }
- dest[d_offset+i] = high_word << shiftAmt;
- return retVal;
-}
-
-APInt::APInt(uint64_t val, unsigned numBits)
- : BitsNum(numBits) {
- assert(BitsNum >= IntegerType::MIN_INT_BITS && "bitwidth too small");
- assert(BitsNum <= IntegerType::MAX_INT_BITS && "bitwidth too large");
- if (isSingleWord())
- VAL = val & (~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitsNum));
- else {
- // Memory allocation and check if successful.
- assert((pVal = new uint64_t[getNumWords()]) &&
- "APInt memory allocation fails!");
- memset(pVal, 0, getNumWords() * 8);
- pVal[0] = val;
- }
-}
-APInt::APInt(unsigned numBits, uint64_t bigVal[])
- : BitsNum(numBits) {
- assert(BitsNum >= IntegerType::MIN_INT_BITS && "bitwidth too small");
- assert(BitsNum <= IntegerType::MAX_INT_BITS && "bitwidth too large");
+APInt::APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[])
+ : BitWidth(numBits), VAL(0) {
+ assert(BitWidth && "Bitwidth too small");
assert(bigVal && "Null pointer detected!");
if (isSingleWord())
- VAL = bigVal[0] & (~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitsNum));
+ VAL = bigVal[0];
else {
- // Memory allocation and check if successful.
- assert((pVal = new uint64_t[getNumWords()]) &&
- "APInt memory allocation fails!");
- // Calculate the actual length of bigVal[].
- unsigned n = sizeof(*bigVal) / sizeof(bigVal[0]);
- unsigned maxN = std::max<unsigned>(n, getNumWords());
- unsigned minN = std::min<unsigned>(n, getNumWords());
- memcpy(pVal, bigVal, (minN - 1) * 8);
- pVal[minN-1] = bigVal[minN-1] & (~uint64_t(0ULL) >> (64 - BitsNum % 64));
- if (maxN == getNumWords())
- memset(pVal+n, 0, (getNumWords() - n) * 8);
+ // Get memory, cleared to 0
+ pVal = getClearedMemory(getNumWords());
+ // Calculate the number of words to copy
+ unsigned words = std::min<unsigned>(numWords, getNumWords());
+ // Copy the words from bigVal to pVal
+ memcpy(pVal, bigVal, words * APINT_WORD_SIZE);
}
+ // Make sure unused high bits are cleared
+ clearUnusedBits();
}
-/// @brief Create a new APInt by translating the char array represented
-/// integer value.
-APInt::APInt(const char StrStart[], unsigned slen, uint8_t radix) {
- StrToAPInt(StrStart, slen, radix);
+APInt::APInt(unsigned numbits, StringRef Str, uint8_t radix)
+ : BitWidth(numbits), VAL(0) {
+ assert(BitWidth && "Bitwidth too small");
+ fromString(numbits, Str, radix);
}
-/// @brief Create a new APInt by translating the string represented
-/// integer value.
-APInt::APInt(const std::string& Val, uint8_t radix) {
- assert(!Val.empty() && "String empty?");
- StrToAPInt(Val.c_str(), Val.size(), radix);
-}
+APInt& APInt::AssignSlowCase(const APInt& RHS) {
+ // Don't do anything for X = X
+ if (this == &RHS)
+ return *this;
-/// @brief Converts a char array into an integer.
-void APInt::StrToAPInt(const char *StrStart, unsigned slen, uint8_t radix) {
- assert((radix == 10 || radix == 8 || radix == 16 || radix == 2) &&
- "Radix should be 2, 8, 10, or 16!");
- assert(StrStart && "String empty?");
- unsigned size = 0;
- // If the radix is a power of 2, read the input
- // from most significant to least significant.
- if ((radix & (radix - 1)) == 0) {
- unsigned nextBitPos = 0, bits_per_digit = radix / 8 + 2;
- uint64_t resDigit = 0;
- BitsNum = slen * bits_per_digit;
- if (getNumWords() > 1)
- assert((pVal = new uint64_t[getNumWords()]) &&
- "APInt memory allocation fails!");
- for (int i = slen - 1; i >= 0; --i) {
- uint64_t digit = StrStart[i] - 48; // '0' == 48.
- resDigit |= digit << nextBitPos;
- nextBitPos += bits_per_digit;
- if (nextBitPos >= 64) {
- if (isSingleWord()) {
- VAL = resDigit;
- break;
- }
- pVal[size++] = resDigit;
- nextBitPos -= 64;
- resDigit = digit >> (bits_per_digit - nextBitPos);
- }
- }
- if (!isSingleWord() && size <= getNumWords())
- pVal[size] = resDigit;
- } else { // General case. The radix is not a power of 2.
- // For 10-radix, the max value of 64-bit integer is 18446744073709551615,
- // and its digits number is 14.
- const unsigned chars_per_word = 20;
- if (slen < chars_per_word ||
- (slen == chars_per_word && // In case the value <= 2^64 - 1
- strcmp(StrStart, "18446744073709551615") <= 0)) {
- BitsNum = 64;
- VAL = strtoull(StrStart, 0, 10);
- } else { // In case the value > 2^64 - 1
- BitsNum = (slen / chars_per_word + 1) * 64;
- assert((pVal = new uint64_t[getNumWords()]) &&
- "APInt memory allocation fails!");
- memset(pVal, 0, getNumWords() * 8);
- unsigned str_pos = 0;
- while (str_pos < slen) {
- unsigned chunk = slen - str_pos;
- if (chunk > chars_per_word - 1)
- chunk = chars_per_word - 1;
- uint64_t resDigit = StrStart[str_pos++] - 48; // 48 == '0'.
- uint64_t big_base = radix;
- while (--chunk > 0) {
- resDigit = resDigit * radix + StrStart[str_pos++] - 48;
- big_base *= radix;
- }
-
- uint64_t carry;
- if (!size)
- carry = resDigit;
- else {
- carry = mul_1(pVal, pVal, size, big_base);
- carry += add_1(pVal, pVal, size, resDigit);
- }
-
- if (carry) pVal[size++] = carry;
- }
- }
+ if (BitWidth == RHS.getBitWidth()) {
+ // assume same bit-width single-word case is already handled
+ assert(!isSingleWord());
+ memcpy(pVal, RHS.pVal, getNumWords() * APINT_WORD_SIZE);
+ return *this;
+ }
+
+ if (isSingleWord()) {
+ // assume case where both are single words is already handled
+ assert(!RHS.isSingleWord());
+ VAL = 0;
+ pVal = getMemory(RHS.getNumWords());
+ memcpy(pVal, RHS.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
+ } else if (getNumWords() == RHS.getNumWords())
+ memcpy(pVal, RHS.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
+ else if (RHS.isSingleWord()) {
+ delete [] pVal;
+ VAL = RHS.VAL;
+ } else {
+ delete [] pVal;
+ pVal = getMemory(RHS.getNumWords());
+ memcpy(pVal, RHS.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
}
+ BitWidth = RHS.BitWidth;
+ return clearUnusedBits();
}
-APInt::APInt(const APInt& APIVal)
- : BitsNum(APIVal.BitsNum) {
- if (isSingleWord()) VAL = APIVal.VAL;
+APInt& APInt::operator=(uint64_t RHS) {
+ if (isSingleWord())
+ VAL = RHS;
else {
- // Memory allocation and check if successful.
- assert((pVal = new uint64_t[getNumWords()]) &&
- "APInt memory allocation fails!");
- memcpy(pVal, APIVal.pVal, getNumWords() * 8);
+ pVal[0] = RHS;
+ memset(pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
}
+ return clearUnusedBits();
}
-APInt::~APInt() {
- if (!isSingleWord() && pVal) delete[] pVal;
-}
+/// Profile - This method 'profiles' an APInt for use with FoldingSet.
+void APInt::Profile(FoldingSetNodeID& ID) const {
+ ID.AddInteger(BitWidth);
-/// @brief Copy assignment operator. Create a new object from the given
-/// APInt one by initialization.
-APInt& APInt::operator=(const APInt& RHS) {
- if (isSingleWord()) VAL = RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
- else {
- unsigned minN = std::min(getNumWords(), RHS.getNumWords());
- memcpy(pVal, RHS.isSingleWord() ? &RHS.VAL : RHS.pVal, minN * 8);
- if (getNumWords() != minN)
- memset(pVal + minN, 0, (getNumWords() - minN) * 8);
+ if (isSingleWord()) {
+ ID.AddInteger(VAL);
+ return;
}
- return *this;
+
+ unsigned NumWords = getNumWords();
+ for (unsigned i = 0; i < NumWords; ++i)
+ ID.AddInteger(pVal[i]);
}
-/// @brief Assignment operator. Assigns a common case integer value to
-/// the APInt.
-APInt& APInt::operator=(uint64_t RHS) {
- if (isSingleWord()) VAL = RHS;
- else {
- pVal[0] = RHS;
- memset(pVal, 0, (getNumWords() - 1) * 8);
+/// add_1 - This function adds a single "digit" integer, y, to the multiple
+/// "digit" integer array, x[]. x[] is modified to reflect the addition and
+/// 1 is returned if there is a carry out, otherwise 0 is returned.
+/// @returns the carry of the addition.
+static bool add_1(uint64_t dest[], uint64_t x[], unsigned len, uint64_t y) {
+ for (unsigned i = 0; i < len; ++i) {
+ dest[i] = y + x[i];
+ if (dest[i] < y)
+ y = 1; // Carry one to next digit.
+ else {
+ y = 0; // No need to carry so exit early
+ break;
+ }
}
- TruncToBits();
- return *this;
+ return y;
}
/// @brief Prefix increment operator. Increments the APInt by one.
APInt& APInt::operator++() {
- if (isSingleWord()) ++VAL;
+ if (isSingleWord())
+ ++VAL;
else
add_1(pVal, pVal, getNumWords(), 1);
- TruncToBits();
- return *this;
+ return clearUnusedBits();
+}
+
+/// sub_1 - This function subtracts a single "digit" (64-bit word), y, from
+/// the multi-digit integer array, x[], propagating the borrowed 1 value until
+/// no further borrowing is neeeded or it runs out of "digits" in x. The result
+/// is 1 if "borrowing" exhausted the digits in x, or 0 if x was not exhausted.
+/// In other words, if y > x then this function returns 1, otherwise 0.
+/// @returns the borrow out of the subtraction
+static bool sub_1(uint64_t x[], unsigned len, uint64_t y) {
+ for (unsigned i = 0; i < len; ++i) {
+ uint64_t X = x[i];
+ x[i] -= y;
+ if (y > X)
+ y = 1; // We have to "borrow 1" from next "digit"
+ else {
+ y = 0; // No need to borrow
+ break; // Remaining digits are unchanged so exit early
+ }
+ }
+ return bool(y);
}
/// @brief Prefix decrement operator. Decrements the APInt by one.
APInt& APInt::operator--() {
- if (isSingleWord()) --VAL;
+ if (isSingleWord())
+ --VAL;
else
sub_1(pVal, getNumWords(), 1);
- TruncToBits();
- return *this;
+ return clearUnusedBits();
+}
+
+/// add - This function adds the integer array x to the integer array Y and
+/// places the result in dest.
+/// @returns the carry out from the addition
+/// @brief General addition of 64-bit integer arrays
+static bool add(uint64_t *dest, const uint64_t *x, const uint64_t *y,
+ unsigned len) {
+ bool carry = false;
+ for (unsigned i = 0; i< len; ++i) {
+ uint64_t limit = std::min(x[i],y[i]); // must come first in case dest == x
+ dest[i] = x[i] + y[i] + carry;
+ carry = dest[i] < limit || (carry && dest[i] == limit);
+ }
+ return carry;
}
-/// @brief Addition assignment operator. Adds this APInt by the given APInt&
-/// RHS and assigns the result to this APInt.
+/// Adds the RHS APint to this APInt.
+/// @returns this, after addition of RHS.
+/// @brief Addition assignment operator.
APInt& APInt::operator+=(const APInt& RHS) {
- if (isSingleWord()) VAL += RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord())
+ VAL += RHS.VAL;
else {
- if (RHS.isSingleWord()) add_1(pVal, pVal, getNumWords(), RHS.VAL);
- else {
- if (getNumWords() <= RHS.getNumWords())
- add(pVal, pVal, RHS.pVal, getNumWords());
- else {
- uint64_t carry = add(pVal, pVal, RHS.pVal, RHS.getNumWords());
- add_1(pVal + RHS.getNumWords(), pVal + RHS.getNumWords(),
- getNumWords() - RHS.getNumWords(), carry);
- }
- }
+ add(pVal, pVal, RHS.pVal, getNumWords());
}
- TruncToBits();
- return *this;
+ return clearUnusedBits();
+}
+
+/// Subtracts the integer array y from the integer array x
+/// @returns returns the borrow out.
+/// @brief Generalized subtraction of 64-bit integer arrays.
+static bool sub(uint64_t *dest, const uint64_t *x, const uint64_t *y,
+ unsigned len) {
+ bool borrow = false;
+ for (unsigned i = 0; i < len; ++i) {
+ uint64_t x_tmp = borrow ? x[i] - 1 : x[i];
+ borrow = y[i] > x_tmp || (borrow && x[i] == 0);
+ dest[i] = x_tmp - y[i];
+ }
+ return borrow;
}
-/// @brief Subtraction assignment operator. Subtracts this APInt by the given
-/// APInt &RHS and assigns the result to this APInt.
+/// Subtracts the RHS APInt from this APInt
+/// @returns this, after subtraction
+/// @brief Subtraction assignment operator.
APInt& APInt::operator-=(const APInt& RHS) {
- if (isSingleWord())
- VAL -= RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
- else {
- if (RHS.isSingleWord())
- sub_1(pVal, getNumWords(), RHS.VAL);
- else {
- if (RHS.getNumWords() < getNumWords()) {
- uint64_t carry = sub(pVal, pVal, RHS.pVal, RHS.getNumWords());
- sub_1(pVal + RHS.getNumWords(), getNumWords() - RHS.getNumWords(), carry);
- }
- else
- sub(pVal, pVal, RHS.pVal, getNumWords());
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord())
+ VAL -= RHS.VAL;
+ else
+ sub(pVal, pVal, RHS.pVal, getNumWords());
+ return clearUnusedBits();
+}
+
+/// Multiplies an integer array, x, by a uint64_t integer and places the result
+/// into dest.
+/// @returns the carry out of the multiplication.
+/// @brief Multiply a multi-digit APInt by a single digit (64-bit) integer.
+static uint64_t mul_1(uint64_t dest[], uint64_t x[], unsigned len, uint64_t y) {
+ // Split y into high 32-bit part (hy) and low 32-bit part (ly)
+ uint64_t ly = y & 0xffffffffULL, hy = y >> 32;
+ uint64_t carry = 0;
+
+ // For each digit of x.
+ for (unsigned i = 0; i < len; ++i) {
+ // Split x into high and low words
+ uint64_t lx = x[i] & 0xffffffffULL;
+ uint64_t hx = x[i] >> 32;
+ // hasCarry - A flag to indicate if there is a carry to the next digit.
+ // hasCarry == 0, no carry
+ // hasCarry == 1, has carry
+ // hasCarry == 2, no carry and the calculation result == 0.
+ uint8_t hasCarry = 0;
+ dest[i] = carry + lx * ly;
+ // Determine if the add above introduces carry.
+ hasCarry = (dest[i] < carry) ? 1 : 0;
+ carry = hx * ly + (dest[i] >> 32) + (hasCarry ? (1ULL << 32) : 0);
+ // The upper limit of carry can be (2^32 - 1)(2^32 - 1) +
+ // (2^32 - 1) + 2^32 = 2^64.
+ hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
+
+ carry += (lx * hy) & 0xffffffffULL;
+ dest[i] = (carry << 32) | (dest[i] & 0xffffffffULL);
+ carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0) +
+ (carry >> 32) + ((lx * hy) >> 32) + hx * hy;
+ }
+ return carry;
+}
+
+/// Multiplies integer array x by integer array y and stores the result into
+/// the integer array dest. Note that dest's size must be >= xlen + ylen.
+/// @brief Generalized multiplicate of integer arrays.
+static void mul(uint64_t dest[], uint64_t x[], unsigned xlen, uint64_t y[],
+ unsigned ylen) {
+ dest[xlen] = mul_1(dest, x, xlen, y[0]);
+ for (unsigned i = 1; i < ylen; ++i) {
+ uint64_t ly = y[i] & 0xffffffffULL, hy = y[i] >> 32;
+ uint64_t carry = 0, lx = 0, hx = 0;
+ for (unsigned j = 0; j < xlen; ++j) {
+ lx = x[j] & 0xffffffffULL;
+ hx = x[j] >> 32;
+ // hasCarry - A flag to indicate if has carry.
+ // hasCarry == 0, no carry
+ // hasCarry == 1, has carry
+ // hasCarry == 2, no carry and the calculation result == 0.
+ uint8_t hasCarry = 0;
+ uint64_t resul = carry + lx * ly;
+ hasCarry = (resul < carry) ? 1 : 0;
+ carry = (hasCarry ? (1ULL << 32) : 0) + hx * ly + (resul >> 32);
+ hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
+
+ carry += (lx * hy) & 0xffffffffULL;
+ resul = (carry << 32) | (resul & 0xffffffffULL);
+ dest[i+j] += resul;
+ carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0)+
+ (carry >> 32) + (dest[i+j] < resul ? 1 : 0) +
+ ((lx * hy) >> 32) + hx * hy;
}
+ dest[i+xlen] = carry;
}
- TruncToBits();
- return *this;
}
-/// @brief Multiplication assignment operator. Multiplies this APInt by the
-/// given APInt& RHS and assigns the result to this APInt.
APInt& APInt::operator*=(const APInt& RHS) {
- if (isSingleWord()) VAL *= RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
- else {
- // one-based first non-zero bit position.
- unsigned first = getNumWords() * APINT_BITS_PER_WORD - CountLeadingZeros();
- unsigned xlen = !first ? 0 : whichWord(first - 1) + 1;
- if (!xlen)
- return *this;
- else if (RHS.isSingleWord())
- mul_1(pVal, pVal, xlen, RHS.VAL);
- else {
- first = RHS.getNumWords() * APINT_BITS_PER_WORD - RHS.CountLeadingZeros();
- unsigned ylen = !first ? 0 : whichWord(first - 1) + 1;
- if (!ylen) {
- memset(pVal, 0, getNumWords() * 8);
- return *this;
- }
- uint64_t *dest = new uint64_t[xlen+ylen];
- assert(dest && "Memory Allocation Failed!");
- mul(dest, pVal, xlen, RHS.pVal, ylen);
- memcpy(pVal, dest, ((xlen + ylen >= getNumWords()) ?
- getNumWords() : xlen + ylen) * 8);
- delete[] dest;
- }
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord()) {
+ VAL *= RHS.VAL;
+ clearUnusedBits();
+ return *this;
+ }
+
+ // Get some bit facts about LHS and check for zero
+ unsigned lhsBits = getActiveBits();
+ unsigned lhsWords = !lhsBits ? 0 : whichWord(lhsBits - 1) + 1;
+ if (!lhsWords)
+ // 0 * X ===> 0
+ return *this;
+
+ // Get some bit facts about RHS and check for zero
+ unsigned rhsBits = RHS.getActiveBits();
+ unsigned rhsWords = !rhsBits ? 0 : whichWord(rhsBits - 1) + 1;
+ if (!rhsWords) {
+ // X * 0 ===> 0
+ clear();
+ return *this;
}
- TruncToBits();
+
+ // Allocate space for the result
+ unsigned destWords = rhsWords + lhsWords;
+ uint64_t *dest = getMemory(destWords);
+
+ // Perform the long multiply
+ mul(dest, pVal, lhsWords, RHS.pVal, rhsWords);
+
+ // Copy result back into *this
+ clear();
+ unsigned wordsToCopy = destWords >= getNumWords() ? getNumWords() : destWords;
+ memcpy(pVal, dest, wordsToCopy * APINT_WORD_SIZE);
+
+ // delete dest array and return
+ delete[] dest;
return *this;
}
-/// @brief Bitwise AND assignment operator. Performs bitwise AND operation on
-/// this APInt and the given APInt& RHS, assigns the result to this APInt.
APInt& APInt::operator&=(const APInt& RHS) {
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord()) {
- if (RHS.isSingleWord()) VAL &= RHS.VAL;
- else VAL &= RHS.pVal[0];
- } else {
- if (RHS.isSingleWord()) {
- memset(pVal, 0, (getNumWords() - 1) * 8);
- pVal[0] &= RHS.VAL;
- } else {
- unsigned minwords = getNumWords() < RHS.getNumWords() ?
- getNumWords() : RHS.getNumWords();
- for (unsigned i = 0; i < minwords; ++i)
- pVal[i] &= RHS.pVal[i];
- if (getNumWords() > minwords)
- memset(pVal+minwords, 0, (getNumWords() - minwords) * 8);
- }
+ VAL &= RHS.VAL;
+ return *this;
}
+ unsigned numWords = getNumWords();
+ for (unsigned i = 0; i < numWords; ++i)
+ pVal[i] &= RHS.pVal[i];
return *this;
}
-/// @brief Bitwise OR assignment operator. Performs bitwise OR operation on
-/// this APInt and the given APInt& RHS, assigns the result to this APInt.
APInt& APInt::operator|=(const APInt& RHS) {
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord()) {
- if (RHS.isSingleWord()) VAL |= RHS.VAL;
- else VAL |= RHS.pVal[0];
- } else {
- if (RHS.isSingleWord()) {
- pVal[0] |= RHS.VAL;
- } else {
- unsigned minwords = getNumWords() < RHS.getNumWords() ?
- getNumWords() : RHS.getNumWords();
- for (unsigned i = 0; i < minwords; ++i)
- pVal[i] |= RHS.pVal[i];
- }
+ VAL |= RHS.VAL;
+ return *this;
}
- TruncToBits();
+ unsigned numWords = getNumWords();
+ for (unsigned i = 0; i < numWords; ++i)
+ pVal[i] |= RHS.pVal[i];
return *this;
}
-/// @brief Bitwise XOR assignment operator. Performs bitwise XOR operation on
-/// this APInt and the given APInt& RHS, assigns the result to this APInt.
APInt& APInt::operator^=(const APInt& RHS) {
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord()) {
- if (RHS.isSingleWord()) VAL ^= RHS.VAL;
- else VAL ^= RHS.pVal[0];
- } else {
- if (RHS.isSingleWord()) {
- for (unsigned i = 0; i < getNumWords(); ++i)
- pVal[i] ^= RHS.VAL;
- } else {
- unsigned minwords = getNumWords() < RHS.getNumWords() ?
- getNumWords() : RHS.getNumWords();
- for (unsigned i = 0; i < minwords; ++i)
- pVal[i] ^= RHS.pVal[i];
- if (getNumWords() > minwords)
- for (unsigned i = minwords; i < getNumWords(); ++i)
- pVal[i] ^= 0;
- }
+ VAL ^= RHS.VAL;
+ this->clearUnusedBits();
+ return *this;
}
- TruncToBits();
- return *this;
+ unsigned numWords = getNumWords();
+ for (unsigned i = 0; i < numWords; ++i)
+ pVal[i] ^= RHS.pVal[i];
+ return clearUnusedBits();
}
-/// @brief Bitwise AND operator. Performs bitwise AND operation on this APInt
-/// and the given APInt& RHS.
-APInt APInt::operator&(const APInt& RHS) const {
- APInt API(RHS);
- return API &= *this;
+APInt APInt::AndSlowCase(const APInt& RHS) const {
+ unsigned numWords = getNumWords();
+ uint64_t* val = getMemory(numWords);
+ for (unsigned i = 0; i < numWords; ++i)
+ val[i] = pVal[i] & RHS.pVal[i];
+ return APInt(val, getBitWidth());
}
-/// @brief Bitwise OR operator. Performs bitwise OR operation on this APInt
-/// and the given APInt& RHS.
-APInt APInt::operator|(const APInt& RHS) const {
- APInt API(RHS);
- API |= *this;
- API.TruncToBits();
- return API;
+APInt APInt::OrSlowCase(const APInt& RHS) const {
+ unsigned numWords = getNumWords();
+ uint64_t *val = getMemory(numWords);
+ for (unsigned i = 0; i < numWords; ++i)
+ val[i] = pVal[i] | RHS.pVal[i];
+ return APInt(val, getBitWidth());
}
-/// @brief Bitwise XOR operator. Performs bitwise XOR operation on this APInt
-/// and the given APInt& RHS.
-APInt APInt::operator^(const APInt& RHS) const {
- APInt API(RHS);
- API ^= *this;
- API.TruncToBits();
- return API;
-}
-
-/// @brief Logical AND operator. Performs logical AND operation on this APInt
-/// and the given APInt& RHS.
-bool APInt::operator&&(const APInt& RHS) const {
- if (isSingleWord())
- return RHS.isSingleWord() ? VAL && RHS.VAL : VAL && RHS.pVal[0];
- else if (RHS.isSingleWord())
- return RHS.VAL && pVal[0];
- else {
- unsigned minN = std::min(getNumWords(), RHS.getNumWords());
- for (unsigned i = 0; i < minN; ++i)
- if (pVal[i] && RHS.pVal[i])
- return true;
- }
- return false;
-}
+APInt APInt::XorSlowCase(const APInt& RHS) const {
+ unsigned numWords = getNumWords();
+ uint64_t *val = getMemory(numWords);
+ for (unsigned i = 0; i < numWords; ++i)
+ val[i] = pVal[i] ^ RHS.pVal[i];
-/// @brief Logical OR operator. Performs logical OR operation on this APInt
-/// and the given APInt& RHS.
-bool APInt::operator||(const APInt& RHS) const {
- if (isSingleWord())
- return RHS.isSingleWord() ? VAL || RHS.VAL : VAL || RHS.pVal[0];
- else if (RHS.isSingleWord())
- return RHS.VAL || pVal[0];
- else {
- unsigned minN = std::min(getNumWords(), RHS.getNumWords());
- for (unsigned i = 0; i < minN; ++i)
- if (pVal[i] || RHS.pVal[i])
- return true;
- }
- return false;
+ // 0^0==1 so clear the high bits in case they got set.
+ return APInt(val, getBitWidth()).clearUnusedBits();
}
-/// @brief Logical negation operator. Performs logical negation operation on
-/// this APInt.
bool APInt::operator !() const {
if (isSingleWord())
return !VAL;
- else
- for (unsigned i = 0; i < getNumWords(); ++i)
- if (pVal[i])
- return false;
+
+ for (unsigned i = 0; i < getNumWords(); ++i)
+ if (pVal[i])
+ return false;
return true;
}
-/// @brief Multiplication operator. Multiplies this APInt by the given APInt&
-/// RHS.
APInt APInt::operator*(const APInt& RHS) const {
- APInt API(RHS);
- API *= *this;
- API.TruncToBits();
- return API;
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord())
+ return APInt(BitWidth, VAL * RHS.VAL);
+ APInt Result(*this);
+ Result *= RHS;
+ return Result.clearUnusedBits();
}
-/// @brief Addition operator. Adds this APInt by the given APInt& RHS.
APInt APInt::operator+(const APInt& RHS) const {
- APInt API(*this);
- API += RHS;
- API.TruncToBits();
- return API;
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord())
+ return APInt(BitWidth, VAL + RHS.VAL);
+ APInt Result(BitWidth, 0);
+ add(Result.pVal, this->pVal, RHS.pVal, getNumWords());
+ return Result.clearUnusedBits();
}
-/// @brief Subtraction operator. Subtracts this APInt by the given APInt& RHS
APInt APInt::operator-(const APInt& RHS) const {
- APInt API(*this);
- API -= RHS;
- return API;
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord())
+ return APInt(BitWidth, VAL - RHS.VAL);
+ APInt Result(BitWidth, 0);
+ sub(Result.pVal, this->pVal, RHS.pVal, getNumWords());
+ return Result.clearUnusedBits();
}
-/// @brief Array-indexing support.
bool APInt::operator[](unsigned bitPosition) const {
- return (maskBit(bitPosition) & (isSingleWord() ?
- VAL : pVal[whichWord(bitPosition)])) != 0;
-}
-
-/// @brief Equality operator. Compare this APInt with the given APInt& RHS
-/// for the validity of the equality relationship.
-bool APInt::operator==(const APInt& RHS) const {
- unsigned n1 = getNumWords() * APINT_BITS_PER_WORD - CountLeadingZeros(),
- n2 = RHS.getNumWords() * APINT_BITS_PER_WORD - RHS.CountLeadingZeros();
- if (n1 != n2) return false;
- else if (isSingleWord())
- return VAL == (RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0]);
- else {
- if (n1 <= 64)
- return pVal[0] == (RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0]);
- for (int i = whichWord(n1 - 1); i >= 0; --i)
- if (pVal[i] != RHS.pVal[i]) return false;
- }
- return true;
+ return (maskBit(bitPosition) &
+ (isSingleWord() ? VAL : pVal[whichWord(bitPosition)])) != 0;
}
-/// @brief Equality operator. Compare this APInt with the given uint64_t value
-/// for the validity of the equality relationship.
-bool APInt::operator==(uint64_t Val) const {
- if (isSingleWord())
- return VAL == Val;
- else {
- unsigned n = getNumWords() * APINT_BITS_PER_WORD - CountLeadingZeros();
- if (n <= 64)
- return pVal[0] == Val;
- else
+bool APInt::EqualSlowCase(const APInt& RHS) const {
+ // Get some facts about the number of bits used in the two operands.
+ unsigned n1 = getActiveBits();
+ unsigned n2 = RHS.getActiveBits();
+
+ // If the number of bits isn't the same, they aren't equal
+ if (n1 != n2)
+ return false;
+
+ // If the number of bits fits in a word, we only need to compare the low word.
+ if (n1 <= APINT_BITS_PER_WORD)
+ return pVal[0] == RHS.pVal[0];
+
+ // Otherwise, compare everything
+ for (int i = whichWord(n1 - 1); i >= 0; --i)
+ if (pVal[i] != RHS.pVal[i])
return false;
- }
+ return true;
}
-/// @brief Less-than operator. Compare this APInt with the given APInt& RHS
-/// for the validity of the less-than relationship.
-bool APInt::operator <(const APInt& RHS) const {
- unsigned n1 = getNumWords() * 64 - CountLeadingZeros(),
- n2 = RHS.getNumWords() * 64 - RHS.CountLeadingZeros();
- if (n1 < n2) return true;
- else if (n1 > n2) return false;
- else if (isSingleWord())
- return VAL < (RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0]);
- else {
- if (n1 <= 64)
- return pVal[0] < (RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0]);
- for (int i = whichWord(n1 - 1); i >= 0; --i) {
- if (pVal[i] > RHS.pVal[i]) return false;
- else if (pVal[i] < RHS.pVal[i]) return true;
- }
- }
- return false;
+bool APInt::EqualSlowCase(uint64_t Val) const {
+ unsigned n = getActiveBits();
+ if (n <= APINT_BITS_PER_WORD)
+ return pVal[0] == Val;
+ else
+ return false;
}
-/// @brief Less-than-or-equal operator. Compare this APInt with the given
-/// APInt& RHS for the validity of the less-than-or-equal relationship.
-bool APInt::operator<=(const APInt& RHS) const {
- return (*this) == RHS || (*this) < RHS;
-}
+bool APInt::ult(const APInt& RHS) const {
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison");
+ if (isSingleWord())
+ return VAL < RHS.VAL;
-/// @brief Greater-than operator. Compare this APInt with the given APInt& RHS
-/// for the validity of the greater-than relationship.
-bool APInt::operator >(const APInt& RHS) const {
- return !((*this) <= RHS);
-}
+ // Get active bit length of both operands
+ unsigned n1 = getActiveBits();
+ unsigned n2 = RHS.getActiveBits();
-/// @brief Greater-than-or-equal operator. Compare this APInt with the given
-/// APInt& RHS for the validity of the greater-than-or-equal relationship.
-bool APInt::operator>=(const APInt& RHS) const {
- return !((*this) < RHS);
-}
+ // If magnitude of LHS is less than RHS, return true.
+ if (n1 < n2)
+ return true;
-/// Set the given bit to 1 whose poition is given as "bitPosition".
-/// @brief Set a given bit to 1.
-APInt& APInt::set(unsigned bitPosition) {
- if (isSingleWord()) VAL |= maskBit(bitPosition);
- else pVal[whichWord(bitPosition)] |= maskBit(bitPosition);
- return *this;
-}
+ // If magnitude of RHS is greather than LHS, return false.
+ if (n2 < n1)
+ return false;
-/// @brief Set every bit to 1.
-APInt& APInt::set() {
- if (isSingleWord()) VAL = -1ULL;
- else
- for (unsigned i = 0; i < getNumWords(); ++i)
- pVal[i] = -1ULL;
- return *this;
+ // If they bot fit in a word, just compare the low order word
+ if (n1 <= APINT_BITS_PER_WORD && n2 <= APINT_BITS_PER_WORD)
+ return pVal[0] < RHS.pVal[0];
+
+ // Otherwise, compare all words
+ unsigned topWord = whichWord(std::max(n1,n2)-1);
+ for (int i = topWord; i >= 0; --i) {
+ if (pVal[i] > RHS.pVal[i])
+ return false;
+ if (pVal[i] < RHS.pVal[i])
+ return true;
+ }
+ return false;
}
-/// Set the given bit to 0 whose position is given as "bitPosition".
-/// @brief Set a given bit to 0.
-APInt& APInt::clear(unsigned bitPosition) {
- if (isSingleWord()) VAL &= ~maskBit(bitPosition);
- else pVal[whichWord(bitPosition)] &= ~maskBit(bitPosition);
- return *this;
+bool APInt::slt(const APInt& RHS) const {
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison");
+ if (isSingleWord()) {
+ int64_t lhsSext = (int64_t(VAL) << (64-BitWidth)) >> (64-BitWidth);
+ int64_t rhsSext = (int64_t(RHS.VAL) << (64-BitWidth)) >> (64-BitWidth);
+ return lhsSext < rhsSext;
+ }
+
+ APInt lhs(*this);
+ APInt rhs(RHS);
+ bool lhsNeg = isNegative();
+ bool rhsNeg = rhs.isNegative();
+ if (lhsNeg) {
+ // Sign bit is set so perform two's complement to make it positive
+ lhs.flip();
+ lhs++;
+ }
+ if (rhsNeg) {
+ // Sign bit is set so perform two's complement to make it positive
+ rhs.flip();
+ rhs++;
+ }
+
+ // Now we have unsigned values to compare so do the comparison if necessary
+ // based on the negativeness of the values.
+ if (lhsNeg)
+ if (rhsNeg)
+ return lhs.ugt(rhs);
+ else
+ return true;
+ else if (rhsNeg)
+ return false;
+ else
+ return lhs.ult(rhs);
}
-/// @brief Set every bit to 0.
-APInt& APInt::clear() {
- if (isSingleWord()) VAL = 0;
- else
- memset(pVal, 0, getNumWords() * 8);
+APInt& APInt::set(unsigned bitPosition) {
+ if (isSingleWord())
+ VAL |= maskBit(bitPosition);
+ else
+ pVal[whichWord(bitPosition)] |= maskBit(bitPosition);
return *this;
}
-/// @brief Bitwise NOT operator. Performs a bitwise logical NOT operation on
-/// this APInt.
-APInt APInt::operator~() const {
- APInt API(*this);
- API.flip();
- return API;
+/// Set the given bit to 0 whose position is given as "bitPosition".
+/// @brief Set a given bit to 0.
+APInt& APInt::clear(unsigned bitPosition) {
+ if (isSingleWord())
+ VAL &= ~maskBit(bitPosition);
+ else
+ pVal[whichWord(bitPosition)] &= ~maskBit(bitPosition);
+ return *this;
}
/// @brief Toggle every bit to its opposite value.
-APInt& APInt::flip() {
- if (isSingleWord()) VAL = (~(VAL << (64 - BitsNum))) >> (64 - BitsNum);
- else {
- unsigned i = 0;
- for (; i < getNumWords() - 1; ++i)
- pVal[i] = ~pVal[i];
- unsigned offset = 64 - (BitsNum - 64 * (i - 1));
- pVal[i] = (~(pVal[i] << offset)) >> offset;
- }
- return *this;
-}
-/// Toggle a given bit to its opposite value whose position is given
+/// Toggle a given bit to its opposite value whose position is given
/// as "bitPosition".
/// @brief Toggles a given bit to its opposite value.
APInt& APInt::flip(unsigned bitPosition) {
- assert(bitPosition < BitsNum && "Out of the bit-width range!");
+ assert(bitPosition < BitWidth && "Out of the bit-width range!");
if ((*this)[bitPosition]) clear(bitPosition);
else set(bitPosition);
return *this;
}
-/// to_string - This function translates the APInt into a string.
-std::string APInt::to_string(uint8_t radix) const {
+unsigned APInt::getBitsNeeded(StringRef str, uint8_t radix) {
+ assert(!str.empty() && "Invalid string length");
assert((radix == 10 || radix == 8 || radix == 16 || radix == 2) &&
"Radix should be 2, 8, 10, or 16!");
- char *buf = 0;
- unsigned n = getNumWords() * 64 - CountLeadingZeros();
- std::string format = radix == 8 ?
- "%0*llo" : (radix == 10 ? "%0*llu" : "%0*llx");
- // If the radix is a power of 2, set the format of ostringstream,
- // and output the value into buf.
- if ((radix & (radix - 1)) == 0) {
- assert((buf = new char[n / Log2_32(radix) + 2]) &&
- "Memory allocation failed");
- if (isSingleWord())
- sprintf(buf, format.c_str(), 0, VAL);
- else {
- unsigned offset = sprintf(buf, format.c_str(), 0, pVal[whichWord(n-1)]);
- for (int i = whichWord(n-1) - 1; i >= 0; --i)
- offset += sprintf(buf + offset, format.c_str(),
- 64 / Log2_32(radix) + (64 % Log2_32(radix) ? 1 : 0), pVal[i]);
- }
+
+ size_t slen = str.size();
+
+ // Each computation below needs to know if it's negative.
+ StringRef::iterator p = str.begin();
+ unsigned isNegative = *p == '-';
+ if (*p == '-' || *p == '+') {
+ p++;
+ slen--;
+ assert(slen && "String is only a sign, needs a value.");
}
- else { // If the radix = 10, need to translate the value into a
- // string.
- assert((buf = new char[(n / 64 + 1) * 20]) && "Memory allocation failed");
- if (isSingleWord())
- sprintf(buf, format.c_str(), 0, VAL);
- else {
- // FIXME: To be supported.
- }
+
+ // For radixes of power-of-two values, the bits required is accurately and
+ // easily computed
+ if (radix == 2)
+ return slen + isNegative;
+ if (radix == 8)
+ return slen * 3 + isNegative;
+ if (radix == 16)
+ return slen * 4 + isNegative;
+
+ // This is grossly inefficient but accurate. We could probably do something
+ // with a computation of roughly slen*64/20 and then adjust by the value of
+ // the first few digits. But, I'm not sure how accurate that could be.
+
+ // Compute a sufficient number of bits that is always large enough but might
+ // be too large. This avoids the assertion in the constructor. This
+ // calculation doesn't work appropriately for the numbers 0-9, so just use 4
+ // bits in that case.
+ unsigned sufficient = slen == 1 ? 4 : slen * 64/18;
+
+ // Convert to the actual binary value.
+ APInt tmp(sufficient, StringRef(p, slen), radix);
+
+ // Compute how many bits are required. If the log is infinite, assume we need
+ // just bit.
+ unsigned log = tmp.logBase2();
+ if (log == (unsigned)-1) {
+ return isNegative + 1;
+ } else {
+ return isNegative + log + 1;
}
- std::string retStr(buf);
- delete[] buf;
- return retStr;
}
-/// getMaxValue - This function returns the largest value
-/// for an APInt of the specified bit-width and if isSign == true,
-/// it should be largest signed value, otherwise unsigned value.
-APInt APInt::getMaxValue(unsigned numBits, bool isSign) {
- APInt APIVal(numBits, 1);
- APIVal.set();
- return isSign ? APIVal.clear(numBits) : APIVal;
-}
+// From http://www.burtleburtle.net, byBob Jenkins.
+// When targeting x86, both GCC and LLVM seem to recognize this as a
+// rotate instruction.
+#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
+
+// From http://www.burtleburtle.net, by Bob Jenkins.
+#define mix(a,b,c) \
+ { \
+ a -= c; a ^= rot(c, 4); c += b; \
+ b -= a; b ^= rot(a, 6); a += c; \
+ c -= b; c ^= rot(b, 8); b += a; \
+ a -= c; a ^= rot(c,16); c += b; \
+ b -= a; b ^= rot(a,19); a += c; \
+ c -= b; c ^= rot(b, 4); b += a; \
+ }
-/// getMinValue - This function returns the smallest value for
-/// an APInt of the given bit-width and if isSign == true,
-/// it should be smallest signed value, otherwise zero.
-APInt APInt::getMinValue(unsigned numBits, bool isSign) {
- APInt APIVal(0, numBits);
- return isSign ? APIVal : APIVal.set(numBits);
-}
+// From http://www.burtleburtle.net, by Bob Jenkins.
+#define final(a,b,c) \
+ { \
+ c ^= b; c -= rot(b,14); \
+ a ^= c; a -= rot(c,11); \
+ b ^= a; b -= rot(a,25); \
+ c ^= b; c -= rot(b,16); \
+ a ^= c; a -= rot(c,4); \
+ b ^= a; b -= rot(a,14); \
+ c ^= b; c -= rot(b,24); \
+ }
-/// getAllOnesValue - This function returns an all-ones value for
-/// an APInt of the specified bit-width.
-APInt APInt::getAllOnesValue(unsigned numBits) {
- return getMaxValue(numBits, false);
-}
+// hashword() was adapted from http://www.burtleburtle.net, by Bob
+// Jenkins. k is a pointer to an array of uint32_t values; length is
+// the length of the key, in 32-bit chunks. This version only handles
+// keys that are a multiple of 32 bits in size.
+static inline uint32_t hashword(const uint64_t *k64, size_t length)
+{
+ const uint32_t *k = reinterpret_cast<const uint32_t *>(k64);
+ uint32_t a,b,c;
+
+ /* Set up the internal state */
+ a = b = c = 0xdeadbeef + (((uint32_t)length)<<2);
+
+ /*------------------------------------------------- handle most of the key */
+ while (length > 3) {
+ a += k[0];
+ b += k[1];
+ c += k[2];
+ mix(a,b,c);
+ length -= 3;
+ k += 3;
+ }
-/// getNullValue - This function creates an '0' value for an
-/// APInt of the specified bit-width.
-APInt APInt::getNullValue(unsigned numBits) {
- return getMinValue(numBits, true);
+ /*------------------------------------------- handle the last 3 uint32_t's */
+ switch (length) { /* all the case statements fall through */
+ case 3 : c+=k[2];
+ case 2 : b+=k[1];
+ case 1 : a+=k[0];
+ final(a,b,c);
+ case 0: /* case 0: nothing left to add */
+ break;
+ }
+ /*------------------------------------------------------ report the result */
+ return c;
+}
+
+// hashword8() was adapted from http://www.burtleburtle.net, by Bob
+// Jenkins. This computes a 32-bit hash from one 64-bit word. When
+// targeting x86 (32 or 64 bit), both LLVM and GCC compile this
+// function into about 35 instructions when inlined.
+static inline uint32_t hashword8(const uint64_t k64)
+{
+ uint32_t a,b,c;
+ a = b = c = 0xdeadbeef + 4;
+ b += k64 >> 32;
+ a += k64 & 0xffffffff;
+ final(a,b,c);
+ return c;
+}
+#undef final
+#undef mix
+#undef rot
+
+uint64_t APInt::getHashValue() const {
+ uint64_t hash;
+ if (isSingleWord())
+ hash = hashword8(VAL);
+ else
+ hash = hashword(pVal, getNumWords()*2);
+ return hash;
}
/// HiBits - This function returns the high "numBits" bits of this APInt.
-APInt APInt::HiBits(unsigned numBits) const {
- return APIntOps::lshr(*this, BitsNum - numBits);
+APInt APInt::getHiBits(unsigned numBits) const {
+ return APIntOps::lshr(*this, BitWidth - numBits);
}
/// LoBits - This function returns the low "numBits" bits of this APInt.
-APInt APInt::LoBits(unsigned numBits) const {
- return APIntOps::lshr(APIntOps::shl(*this, BitsNum - numBits),
- BitsNum - numBits);
+APInt APInt::getLoBits(unsigned numBits) const {
+ return APIntOps::lshr(APIntOps::shl(*this, BitWidth - numBits),
+ BitWidth - numBits);
}
-/// CountLeadingZeros - This function is a APInt version corresponding to
-/// llvm/include/llvm/Support/MathExtras.h's function
-/// CountLeadingZeros_{32, 64}. It performs platform optimal form of counting
-/// the number of zeros from the most significant bit to the first one bit.
-/// @returns numWord() * 64 if the value is zero.
-unsigned APInt::CountLeadingZeros() const {
- if (isSingleWord())
- return CountLeadingZeros_64(VAL);
- unsigned Count = 0;
- for (int i = getNumWords() - 1; i >= 0; --i) {
- unsigned tmp = CountLeadingZeros_64(pVal[i]);
- Count += tmp;
- if (tmp != 64)
+bool APInt::isPowerOf2() const {
+ return (!!*this) && !(*this & (*this - APInt(BitWidth,1)));
+}
+
+unsigned APInt::countLeadingZerosSlowCase() const {
+ // Treat the most significand word differently because it might have
+ // meaningless bits set beyond the precision.
+ unsigned BitsInMSW = BitWidth % APINT_BITS_PER_WORD;
+ integerPart MSWMask;
+ if (BitsInMSW) MSWMask = (integerPart(1) << BitsInMSW) - 1;
+ else {
+ MSWMask = ~integerPart(0);
+ BitsInMSW = APINT_BITS_PER_WORD;
+ }
+
+ unsigned i = getNumWords();
+ integerPart MSW = pVal[i-1] & MSWMask;
+ if (MSW)
+ return CountLeadingZeros_64(MSW) - (APINT_BITS_PER_WORD - BitsInMSW);
+
+ unsigned Count = BitsInMSW;
+ for (--i; i > 0u; --i) {
+ if (pVal[i-1] == 0)
+ Count += APINT_BITS_PER_WORD;
+ else {
+ Count += CountLeadingZeros_64(pVal[i-1]);
break;
+ }
}
return Count;
}
-/// CountTrailingZero - This function is a APInt version corresponding to
-/// llvm/include/llvm/Support/MathExtras.h's function
-/// CountTrailingZeros_{32, 64}. It performs platform optimal form of counting
-/// the number of zeros from the least significant bit to the first one bit.
-/// @returns numWord() * 64 if the value is zero.
-unsigned APInt::CountTrailingZeros() const {
+static unsigned countLeadingOnes_64(uint64_t V, unsigned skip) {
+ unsigned Count = 0;
+ if (skip)
+ V <<= skip;
+ while (V && (V & (1ULL << 63))) {
+ Count++;
+ V <<= 1;
+ }
+ return Count;
+}
+
+unsigned APInt::countLeadingOnes() const {
if (isSingleWord())
- return CountTrailingZeros_64(~VAL & (VAL - 1));
- APInt Tmp = ~(*this) & ((*this) - 1);
- return getNumWords() * 64 - Tmp.CountLeadingZeros();
+ return countLeadingOnes_64(VAL, APINT_BITS_PER_WORD - BitWidth);
+
+ unsigned highWordBits = BitWidth % APINT_BITS_PER_WORD;
+ unsigned shift;
+ if (!highWordBits) {
+ highWordBits = APINT_BITS_PER_WORD;
+ shift = 0;
+ } else {
+ shift = APINT_BITS_PER_WORD - highWordBits;
+ }
+ int i = getNumWords() - 1;
+ unsigned Count = countLeadingOnes_64(pVal[i], shift);
+ if (Count == highWordBits) {
+ for (i--; i >= 0; --i) {
+ if (pVal[i] == -1ULL)
+ Count += APINT_BITS_PER_WORD;
+ else {
+ Count += countLeadingOnes_64(pVal[i], 0);
+ break;
+ }
+ }
+ }
+ return Count;
}
-/// CountPopulation - This function is a APInt version corresponding to
-/// llvm/include/llvm/Support/MathExtras.h's function
-/// CountPopulation_{32, 64}. It counts the number of set bits in a value.
-/// @returns 0 if the value is zero.
-unsigned APInt::CountPopulation() const {
+unsigned APInt::countTrailingZeros() const {
if (isSingleWord())
- return CountPopulation_64(VAL);
+ return std::min(unsigned(CountTrailingZeros_64(VAL)), BitWidth);
+ unsigned Count = 0;
+ unsigned i = 0;
+ for (; i < getNumWords() && pVal[i] == 0; ++i)
+ Count += APINT_BITS_PER_WORD;
+ if (i < getNumWords())
+ Count += CountTrailingZeros_64(pVal[i]);
+ return std::min(Count, BitWidth);
+}
+
+unsigned APInt::countTrailingOnesSlowCase() const {
+ unsigned Count = 0;
+ unsigned i = 0;
+ for (; i < getNumWords() && pVal[i] == -1ULL; ++i)
+ Count += APINT_BITS_PER_WORD;
+ if (i < getNumWords())
+ Count += CountTrailingOnes_64(pVal[i]);
+ return std::min(Count, BitWidth);
+}
+
+unsigned APInt::countPopulationSlowCase() const {
unsigned Count = 0;
for (unsigned i = 0; i < getNumWords(); ++i)
Count += CountPopulation_64(pVal[i]);
return Count;
}
-
-/// ByteSwap - This function returns a byte-swapped representation of the
-/// this APInt.
-APInt APInt::ByteSwap() const {
- if (BitsNum <= 32)
- return APInt(BitsNum, ByteSwap_32(unsigned(VAL)));
- else if (BitsNum <= 64)
- return APInt(BitsNum, ByteSwap_64(VAL));
- else
- return *this;
+APInt APInt::byteSwap() const {
+ assert(BitWidth >= 16 && BitWidth % 16 == 0 && "Cannot byteswap!");
+ if (BitWidth == 16)
+ return APInt(BitWidth, ByteSwap_16(uint16_t(VAL)));
+ else if (BitWidth == 32)
+ return APInt(BitWidth, ByteSwap_32(unsigned(VAL)));
+ else if (BitWidth == 48) {
+ unsigned Tmp1 = unsigned(VAL >> 16);
+ Tmp1 = ByteSwap_32(Tmp1);
+ uint16_t Tmp2 = uint16_t(VAL);
+ Tmp2 = ByteSwap_16(Tmp2);
+ return APInt(BitWidth, (uint64_t(Tmp2) << 32) | Tmp1);
+ } else if (BitWidth == 64)
+ return APInt(BitWidth, ByteSwap_64(VAL));
+ else {
+ APInt Result(BitWidth, 0);
+ char *pByte = (char*)Result.pVal;
+ for (unsigned i = 0; i < BitWidth / APINT_WORD_SIZE / 2; ++i) {
+ char Tmp = pByte[i];
+ pByte[i] = pByte[BitWidth / APINT_WORD_SIZE - 1 - i];
+ pByte[BitWidth / APINT_WORD_SIZE - i - 1] = Tmp;
+ }
+ return Result;
+ }
}
-/// GreatestCommonDivisor - This function returns the greatest common
-/// divisor of the two APInt values using Enclid's algorithm.
-APInt llvm::APIntOps::GreatestCommonDivisor(const APInt& API1,
+APInt llvm::APIntOps::GreatestCommonDivisor(const APInt& API1,
const APInt& API2) {
APInt A = API1, B = API2;
while (!!B) {
return A;
}
-/// DoubleRoundToAPInt - This function convert a double value to
-/// a APInt value.
-APInt llvm::APIntOps::DoubleRoundToAPInt(double Double) {
+APInt llvm::APIntOps::RoundDoubleToAPInt(double Double, unsigned width) {
union {
double D;
uint64_t I;
} T;
T.D = Double;
+
+ // Get the sign bit from the highest order bit
bool isNeg = T.I >> 63;
+
+ // Get the 11-bit exponent and adjust for the 1023 bit bias
int64_t exp = ((T.I >> 52) & 0x7ff) - 1023;
+
+ // If the exponent is negative, the value is < 0 so just return 0.
if (exp < 0)
- return APInt(0);
- uint64_t mantissa = ((T.I << 12) >> 12) | (1ULL << 52);
+ return APInt(width, 0u);
+
+ // Extract the mantissa by clearing the top 12 bits (sign + exponent).
+ uint64_t mantissa = (T.I & (~0ULL >> 12)) | 1ULL << 52;
+
+ // If the exponent doesn't shift all bits out of the mantissa
if (exp < 52)
- return isNeg ? -APInt(mantissa >> (52 - exp)) :
- APInt(mantissa >> (52 - exp));
- APInt Tmp(mantissa, exp + 1);
- Tmp = Tmp.shl(exp - 52);
+ return isNeg ? -APInt(width, mantissa >> (52 - exp)) :
+ APInt(width, mantissa >> (52 - exp));
+
+ // If the client didn't provide enough bits for us to shift the mantissa into
+ // then the result is undefined, just return 0
+ if (width <= exp - 52)
+ return APInt(width, 0);
+
+ // Otherwise, we have to shift the mantissa bits up to the right location
+ APInt Tmp(width, mantissa);
+ Tmp = Tmp.shl((unsigned)exp - 52);
return isNeg ? -Tmp : Tmp;
}
-/// APIntRoundToDouble - This function convert this APInt to a double.
+/// RoundToDouble - This function converts this APInt to a double.
/// The layout for double is as following (IEEE Standard 754):
/// --------------------------------------
/// | Sign Exponent Fraction Bias |
/// |-------------------------------------- |
/// | 1[63] 11[62-52] 52[51-00] 1023 |
-/// --------------------------------------
-double APInt::APIntRoundToDouble(bool isSigned) const {
- bool isNeg = isSigned ? (*this)[BitsNum-1] : false;
+/// --------------------------------------
+double APInt::roundToDouble(bool isSigned) const {
+
+ // Handle the simple case where the value is contained in one uint64_t.
+ // It is wrong to optimize getWord(0) to VAL; there might be more than one word.
+ if (isSingleWord() || getActiveBits() <= APINT_BITS_PER_WORD) {
+ if (isSigned) {
+ int64_t sext = (int64_t(getWord(0)) << (64-BitWidth)) >> (64-BitWidth);
+ return double(sext);
+ } else
+ return double(getWord(0));
+ }
+
+ // Determine if the value is negative.
+ bool isNeg = isSigned ? (*this)[BitWidth-1] : false;
+
+ // Construct the absolute value if we're negative.
APInt Tmp(isNeg ? -(*this) : (*this));
- if (Tmp.isSingleWord())
- return isSigned ? double(int64_t(Tmp.VAL)) : double(Tmp.VAL);
- unsigned n = Tmp.getNumWords() * 64 - Tmp.CountLeadingZeros();
- if (n <= 64)
- return isSigned ? double(int64_t(Tmp.pVal[0])) : double(Tmp.pVal[0]);
- // Exponent when normalized to have decimal point directly after
- // leading one. This is stored excess 1023 in the exponent bit field.
- uint64_t exp = n - 1;
-
- // Gross overflow.
- assert(exp <= 1023 && "Infinity value!");
-
- // Number of bits in mantissa including the leading one
- // equals to 53.
+
+ // Figure out how many bits we're using.
+ unsigned n = Tmp.getActiveBits();
+
+ // The exponent (without bias normalization) is just the number of bits
+ // we are using. Note that the sign bit is gone since we constructed the
+ // absolute value.
+ uint64_t exp = n;
+
+ // Return infinity for exponent overflow
+ if (exp > 1023) {
+ if (!isSigned || !isNeg)
+ return std::numeric_limits<double>::infinity();
+ else
+ return -std::numeric_limits<double>::infinity();
+ }
+ exp += 1023; // Increment for 1023 bias
+
+ // Number of bits in mantissa is 52. To obtain the mantissa value, we must
+ // extract the high 52 bits from the correct words in pVal.
uint64_t mantissa;
- if (n % 64 >= 53)
- mantissa = Tmp.pVal[whichWord(n - 1)] >> (n % 64 - 53);
- else
- mantissa = (Tmp.pVal[whichWord(n - 1)] << (53 - n % 64)) |
- (Tmp.pVal[whichWord(n - 1) - 1] >> (11 + n % 64));
+ unsigned hiWord = whichWord(n-1);
+ if (hiWord == 0) {
+ mantissa = Tmp.pVal[0];
+ if (n > 52)
+ mantissa >>= n - 52; // shift down, we want the top 52 bits.
+ } else {
+ assert(hiWord > 0 && "huh?");
+ uint64_t hibits = Tmp.pVal[hiWord] << (52 - n % APINT_BITS_PER_WORD);
+ uint64_t lobits = Tmp.pVal[hiWord-1] >> (11 + n % APINT_BITS_PER_WORD);
+ mantissa = hibits | lobits;
+ }
+
// The leading bit of mantissa is implicit, so get rid of it.
- mantissa &= ~(1ULL << 52);
- uint64_t sign = isNeg ? (1ULL << 63) : 0;
- exp += 1023;
+ uint64_t sign = isNeg ? (1ULL << (APINT_BITS_PER_WORD - 1)) : 0;
union {
double D;
uint64_t I;
return T.D;
}
+// Truncate to new width.
+APInt &APInt::trunc(unsigned width) {
+ assert(width < BitWidth && "Invalid APInt Truncate request");
+ assert(width && "Can't truncate to 0 bits");
+ unsigned wordsBefore = getNumWords();
+ BitWidth = width;
+ unsigned wordsAfter = getNumWords();
+ if (wordsBefore != wordsAfter) {
+ if (wordsAfter == 1) {
+ uint64_t *tmp = pVal;
+ VAL = pVal[0];
+ delete [] tmp;
+ } else {
+ uint64_t *newVal = getClearedMemory(wordsAfter);
+ for (unsigned i = 0; i < wordsAfter; ++i)
+ newVal[i] = pVal[i];
+ delete [] pVal;
+ pVal = newVal;
+ }
+ }
+ return clearUnusedBits();
+}
+
+// Sign extend to a new width.
+APInt &APInt::sext(unsigned width) {
+ assert(width > BitWidth && "Invalid APInt SignExtend request");
+ // If the sign bit isn't set, this is the same as zext.
+ if (!isNegative()) {
+ zext(width);
+ return *this;
+ }
+
+ // The sign bit is set. First, get some facts
+ unsigned wordsBefore = getNumWords();
+ unsigned wordBits = BitWidth % APINT_BITS_PER_WORD;
+ BitWidth = width;
+ unsigned wordsAfter = getNumWords();
+
+ // Mask the high order word appropriately
+ if (wordsBefore == wordsAfter) {
+ unsigned newWordBits = width % APINT_BITS_PER_WORD;
+ // The extension is contained to the wordsBefore-1th word.
+ uint64_t mask = ~0ULL;
+ if (newWordBits)
+ mask >>= APINT_BITS_PER_WORD - newWordBits;
+ mask <<= wordBits;
+ if (wordsBefore == 1)
+ VAL |= mask;
+ else
+ pVal[wordsBefore-1] |= mask;
+ return clearUnusedBits();
+ }
+
+ uint64_t mask = wordBits == 0 ? 0 : ~0ULL << wordBits;
+ uint64_t *newVal = getMemory(wordsAfter);
+ if (wordsBefore == 1)
+ newVal[0] = VAL | mask;
+ else {
+ for (unsigned i = 0; i < wordsBefore; ++i)
+ newVal[i] = pVal[i];
+ newVal[wordsBefore-1] |= mask;
+ }
+ for (unsigned i = wordsBefore; i < wordsAfter; i++)
+ newVal[i] = -1ULL;
+ if (wordsBefore != 1)
+ delete [] pVal;
+ pVal = newVal;
+ return clearUnusedBits();
+}
+
+// Zero extend to a new width.
+APInt &APInt::zext(unsigned width) {
+ assert(width > BitWidth && "Invalid APInt ZeroExtend request");
+ unsigned wordsBefore = getNumWords();
+ BitWidth = width;
+ unsigned wordsAfter = getNumWords();
+ if (wordsBefore != wordsAfter) {
+ uint64_t *newVal = getClearedMemory(wordsAfter);
+ if (wordsBefore == 1)
+ newVal[0] = VAL;
+ else
+ for (unsigned i = 0; i < wordsBefore; ++i)
+ newVal[i] = pVal[i];
+ if (wordsBefore != 1)
+ delete [] pVal;
+ pVal = newVal;
+ }
+ return *this;
+}
+
+APInt &APInt::zextOrTrunc(unsigned width) {
+ if (BitWidth < width)
+ return zext(width);
+ if (BitWidth > width)
+ return trunc(width);
+ return *this;
+}
+
+APInt &APInt::sextOrTrunc(unsigned width) {
+ if (BitWidth < width)
+ return sext(width);
+ if (BitWidth > width)
+ return trunc(width);
+ return *this;
+}
+
+/// Arithmetic right-shift this APInt by shiftAmt.
+/// @brief Arithmetic right-shift function.
+APInt APInt::ashr(const APInt &shiftAmt) const {
+ return ashr((unsigned)shiftAmt.getLimitedValue(BitWidth));
+}
+
/// Arithmetic right-shift this APInt by shiftAmt.
/// @brief Arithmetic right-shift function.
APInt APInt::ashr(unsigned shiftAmt) const {
- APInt API(*this);
- if (API.isSingleWord())
- API.VAL = (((int64_t(API.VAL) << (64 - API.BitsNum)) >> (64 - API.BitsNum))
- >> shiftAmt) & (~uint64_t(0UL) >> (64 - API.BitsNum));
- else {
- if (shiftAmt >= API.BitsNum) {
- memset(API.pVal, API[API.BitsNum-1] ? 1 : 0, (API.getNumWords()-1) * 8);
- API.pVal[API.getNumWords() - 1] = ~uint64_t(0UL) >>
- (64 - API.BitsNum % 64);
- } else {
- unsigned i = 0;
- for (; i < API.BitsNum - shiftAmt; ++i)
- if (API[i+shiftAmt])
- API.set(i);
- else
- API.clear(i);
- for (; i < API.BitsNum; ++i)
- API[API.BitsNum-1] ? API.set(i) : API.clear(i);
+ assert(shiftAmt <= BitWidth && "Invalid shift amount");
+ // Handle a degenerate case
+ if (shiftAmt == 0)
+ return *this;
+
+ // Handle single word shifts with built-in ashr
+ if (isSingleWord()) {
+ if (shiftAmt == BitWidth)
+ return APInt(BitWidth, 0); // undefined
+ else {
+ unsigned SignBit = APINT_BITS_PER_WORD - BitWidth;
+ return APInt(BitWidth,
+ (((int64_t(VAL) << SignBit) >> SignBit) >> shiftAmt));
}
}
- return API;
+
+ // If all the bits were shifted out, the result is, technically, undefined.
+ // We return -1 if it was negative, 0 otherwise. We check this early to avoid
+ // issues in the algorithm below.
+ if (shiftAmt == BitWidth) {
+ if (isNegative())
+ return APInt(BitWidth, -1ULL, true);
+ else
+ return APInt(BitWidth, 0);
+ }
+
+ // Create some space for the result.
+ uint64_t * val = new uint64_t[getNumWords()];
+
+ // Compute some values needed by the following shift algorithms
+ unsigned wordShift = shiftAmt % APINT_BITS_PER_WORD; // bits to shift per word
+ unsigned offset = shiftAmt / APINT_BITS_PER_WORD; // word offset for shift
+ unsigned breakWord = getNumWords() - 1 - offset; // last word affected
+ unsigned bitsInWord = whichBit(BitWidth); // how many bits in last word?
+ if (bitsInWord == 0)
+ bitsInWord = APINT_BITS_PER_WORD;
+
+ // If we are shifting whole words, just move whole words
+ if (wordShift == 0) {
+ // Move the words containing significant bits
+ for (unsigned i = 0; i <= breakWord; ++i)
+ val[i] = pVal[i+offset]; // move whole word
+
+ // Adjust the top significant word for sign bit fill, if negative
+ if (isNegative())
+ if (bitsInWord < APINT_BITS_PER_WORD)
+ val[breakWord] |= ~0ULL << bitsInWord; // set high bits
+ } else {
+ // Shift the low order words
+ for (unsigned i = 0; i < breakWord; ++i) {
+ // This combines the shifted corresponding word with the low bits from
+ // the next word (shifted into this word's high bits).
+ val[i] = (pVal[i+offset] >> wordShift) |
+ (pVal[i+offset+1] << (APINT_BITS_PER_WORD - wordShift));
+ }
+
+ // Shift the break word. In this case there are no bits from the next word
+ // to include in this word.
+ val[breakWord] = pVal[breakWord+offset] >> wordShift;
+
+ // Deal with sign extenstion in the break word, and possibly the word before
+ // it.
+ if (isNegative()) {
+ if (wordShift > bitsInWord) {
+ if (breakWord > 0)
+ val[breakWord-1] |=
+ ~0ULL << (APINT_BITS_PER_WORD - (wordShift - bitsInWord));
+ val[breakWord] |= ~0ULL;
+ } else
+ val[breakWord] |= (~0ULL << (bitsInWord - wordShift));
+ }
+ }
+
+ // Remaining words are 0 or -1, just assign them.
+ uint64_t fillValue = (isNegative() ? -1ULL : 0);
+ for (unsigned i = breakWord+1; i < getNumWords(); ++i)
+ val[i] = fillValue;
+ return APInt(val, BitWidth).clearUnusedBits();
+}
+
+/// Logical right-shift this APInt by shiftAmt.
+/// @brief Logical right-shift function.
+APInt APInt::lshr(const APInt &shiftAmt) const {
+ return lshr((unsigned)shiftAmt.getLimitedValue(BitWidth));
}
/// Logical right-shift this APInt by shiftAmt.
/// @brief Logical right-shift function.
APInt APInt::lshr(unsigned shiftAmt) const {
- APInt API(*this);
- if (API.isSingleWord())
- API.VAL >>= shiftAmt;
- else {
- if (shiftAmt >= API.BitsNum)
- memset(API.pVal, 0, API.getNumWords() * 8);
- unsigned i = 0;
- for (i = 0; i < API.BitsNum - shiftAmt; ++i)
- if (API[i+shiftAmt]) API.set(i);
- else API.clear(i);
- for (; i < API.BitsNum; ++i)
- API.clear(i);
+ if (isSingleWord()) {
+ if (shiftAmt == BitWidth)
+ return APInt(BitWidth, 0);
+ else
+ return APInt(BitWidth, this->VAL >> shiftAmt);
}
- return API;
+
+ // If all the bits were shifted out, the result is 0. This avoids issues
+ // with shifting by the size of the integer type, which produces undefined
+ // results. We define these "undefined results" to always be 0.
+ if (shiftAmt == BitWidth)
+ return APInt(BitWidth, 0);
+
+ // If none of the bits are shifted out, the result is *this. This avoids
+ // issues with shifting by the size of the integer type, which produces
+ // undefined results in the code below. This is also an optimization.
+ if (shiftAmt == 0)
+ return *this;
+
+ // Create some space for the result.
+ uint64_t * val = new uint64_t[getNumWords()];
+
+ // If we are shifting less than a word, compute the shift with a simple carry
+ if (shiftAmt < APINT_BITS_PER_WORD) {
+ uint64_t carry = 0;
+ for (int i = getNumWords()-1; i >= 0; --i) {
+ val[i] = (pVal[i] >> shiftAmt) | carry;
+ carry = pVal[i] << (APINT_BITS_PER_WORD - shiftAmt);
+ }
+ return APInt(val, BitWidth).clearUnusedBits();
+ }
+
+ // Compute some values needed by the remaining shift algorithms
+ unsigned wordShift = shiftAmt % APINT_BITS_PER_WORD;
+ unsigned offset = shiftAmt / APINT_BITS_PER_WORD;
+
+ // If we are shifting whole words, just move whole words
+ if (wordShift == 0) {
+ for (unsigned i = 0; i < getNumWords() - offset; ++i)
+ val[i] = pVal[i+offset];
+ for (unsigned i = getNumWords()-offset; i < getNumWords(); i++)
+ val[i] = 0;
+ return APInt(val,BitWidth).clearUnusedBits();
+ }
+
+ // Shift the low order words
+ unsigned breakWord = getNumWords() - offset -1;
+ for (unsigned i = 0; i < breakWord; ++i)
+ val[i] = (pVal[i+offset] >> wordShift) |
+ (pVal[i+offset+1] << (APINT_BITS_PER_WORD - wordShift));
+ // Shift the break word.
+ val[breakWord] = pVal[breakWord+offset] >> wordShift;
+
+ // Remaining words are 0
+ for (unsigned i = breakWord+1; i < getNumWords(); ++i)
+ val[i] = 0;
+ return APInt(val, BitWidth).clearUnusedBits();
}
/// Left-shift this APInt by shiftAmt.
/// @brief Left-shift function.
-APInt APInt::shl(unsigned shiftAmt) const {
- APInt API(*this);
- if (API.isSingleWord())
- API.VAL <<= shiftAmt;
- else if (shiftAmt >= API.BitsNum)
- memset(API.pVal, 0, API.getNumWords() * 8);
- else {
- if (unsigned offset = shiftAmt / 64) {
- for (unsigned i = API.getNumWords() - 1; i > offset - 1; --i)
- API.pVal[i] = API.pVal[i-offset];
- memset(API.pVal, 0, offset * 8);
+APInt APInt::shl(const APInt &shiftAmt) const {
+ // It's undefined behavior in C to shift by BitWidth or greater.
+ return shl((unsigned)shiftAmt.getLimitedValue(BitWidth));
+}
+
+APInt APInt::shlSlowCase(unsigned shiftAmt) const {
+ // If all the bits were shifted out, the result is 0. This avoids issues
+ // with shifting by the size of the integer type, which produces undefined
+ // results. We define these "undefined results" to always be 0.
+ if (shiftAmt == BitWidth)
+ return APInt(BitWidth, 0);
+
+ // If none of the bits are shifted out, the result is *this. This avoids a
+ // lshr by the words size in the loop below which can produce incorrect
+ // results. It also avoids the expensive computation below for a common case.
+ if (shiftAmt == 0)
+ return *this;
+
+ // Create some space for the result.
+ uint64_t * val = new uint64_t[getNumWords()];
+
+ // If we are shifting less than a word, do it the easy way
+ if (shiftAmt < APINT_BITS_PER_WORD) {
+ uint64_t carry = 0;
+ for (unsigned i = 0; i < getNumWords(); i++) {
+ val[i] = pVal[i] << shiftAmt | carry;
+ carry = pVal[i] >> (APINT_BITS_PER_WORD - shiftAmt);
}
- shiftAmt %= 64;
- unsigned i;
- for (i = API.getNumWords() - 1; i > 0; --i)
- API.pVal[i] = (API.pVal[i] << shiftAmt) |
- (API.pVal[i-1] >> (64-shiftAmt));
- API.pVal[i] <<= shiftAmt;
+ return APInt(val, BitWidth).clearUnusedBits();
}
- return API;
+
+ // Compute some values needed by the remaining shift algorithms
+ unsigned wordShift = shiftAmt % APINT_BITS_PER_WORD;
+ unsigned offset = shiftAmt / APINT_BITS_PER_WORD;
+
+ // If we are shifting whole words, just move whole words
+ if (wordShift == 0) {
+ for (unsigned i = 0; i < offset; i++)
+ val[i] = 0;
+ for (unsigned i = offset; i < getNumWords(); i++)
+ val[i] = pVal[i-offset];
+ return APInt(val,BitWidth).clearUnusedBits();
+ }
+
+ // Copy whole words from this to Result.
+ unsigned i = getNumWords() - 1;
+ for (; i > offset; --i)
+ val[i] = pVal[i-offset] << wordShift |
+ pVal[i-offset-1] >> (APINT_BITS_PER_WORD - wordShift);
+ val[offset] = pVal[0] << wordShift;
+ for (i = 0; i < offset; ++i)
+ val[i] = 0;
+ return APInt(val, BitWidth).clearUnusedBits();
}
-/// Unsigned divide this APInt by APInt RHS.
-/// @brief Unsigned division function for APInt.
-APInt APInt::udiv(const APInt& RHS) const {
- APInt API(*this);
- unsigned first = RHS.getNumWords() * APInt::APINT_BITS_PER_WORD -
- RHS.CountLeadingZeros();
- unsigned ylen = !first ? 0 : APInt::whichWord(first - 1) + 1;
- assert(ylen && "Divided by zero???");
- if (API.isSingleWord()) {
- API.VAL = RHS.isSingleWord() ? (API.VAL / RHS.VAL) :
- (ylen > 1 ? 0 : API.VAL / RHS.pVal[0]);
- } else {
- unsigned first2 = API.getNumWords() * APInt::APINT_BITS_PER_WORD -
- API.CountLeadingZeros();
- unsigned xlen = !first2 ? 0 : APInt::whichWord(first2 - 1) + 1;
- if (!xlen)
- return API;
- else if (API < RHS)
- memset(API.pVal, 0, API.getNumWords() * 8);
- else if (API == RHS) {
- memset(API.pVal, 0, API.getNumWords() * 8);
- API.pVal[0] = 1;
- } else if (xlen == 1)
- API.pVal[0] /= RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
+APInt APInt::rotl(const APInt &rotateAmt) const {
+ return rotl((unsigned)rotateAmt.getLimitedValue(BitWidth));
+}
+
+APInt APInt::rotl(unsigned rotateAmt) const {
+ if (rotateAmt == 0)
+ return *this;
+ // Don't get too fancy, just use existing shift/or facilities
+ APInt hi(*this);
+ APInt lo(*this);
+ hi.shl(rotateAmt);
+ lo.lshr(BitWidth - rotateAmt);
+ return hi | lo;
+}
+
+APInt APInt::rotr(const APInt &rotateAmt) const {
+ return rotr((unsigned)rotateAmt.getLimitedValue(BitWidth));
+}
+
+APInt APInt::rotr(unsigned rotateAmt) const {
+ if (rotateAmt == 0)
+ return *this;
+ // Don't get too fancy, just use existing shift/or facilities
+ APInt hi(*this);
+ APInt lo(*this);
+ lo.lshr(rotateAmt);
+ hi.shl(BitWidth - rotateAmt);
+ return hi | lo;
+}
+
+// Square Root - this method computes and returns the square root of "this".
+// Three mechanisms are used for computation. For small values (<= 5 bits),
+// a table lookup is done. This gets some performance for common cases. For
+// values using less than 52 bits, the value is converted to double and then
+// the libc sqrt function is called. The result is rounded and then converted
+// back to a uint64_t which is then used to construct the result. Finally,
+// the Babylonian method for computing square roots is used.
+APInt APInt::sqrt() const {
+
+ // Determine the magnitude of the value.
+ unsigned magnitude = getActiveBits();
+
+ // Use a fast table for some small values. This also gets rid of some
+ // rounding errors in libc sqrt for small values.
+ if (magnitude <= 5) {
+ static const uint8_t results[32] = {
+ /* 0 */ 0,
+ /* 1- 2 */ 1, 1,
+ /* 3- 6 */ 2, 2, 2, 2,
+ /* 7-12 */ 3, 3, 3, 3, 3, 3,
+ /* 13-20 */ 4, 4, 4, 4, 4, 4, 4, 4,
+ /* 21-30 */ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ /* 31 */ 6
+ };
+ return APInt(BitWidth, results[ (isSingleWord() ? VAL : pVal[0]) ]);
+ }
+
+ // If the magnitude of the value fits in less than 52 bits (the precision of
+ // an IEEE double precision floating point value), then we can use the
+ // libc sqrt function which will probably use a hardware sqrt computation.
+ // This should be faster than the algorithm below.
+ if (magnitude < 52) {
+#if HAVE_ROUND
+ return APInt(BitWidth,
+ uint64_t(::round(::sqrt(double(isSingleWord()?VAL:pVal[0])))));
+#else
+ return APInt(BitWidth,
+ uint64_t(::sqrt(double(isSingleWord()?VAL:pVal[0]))) + 0.5);
+#endif
+ }
+
+ // Okay, all the short cuts are exhausted. We must compute it. The following
+ // is a classical Babylonian method for computing the square root. This code
+ // was adapted to APINt from a wikipedia article on such computations.
+ // See http://www.wikipedia.org/ and go to the page named
+ // Calculate_an_integer_square_root.
+ unsigned nbits = BitWidth, i = 4;
+ APInt testy(BitWidth, 16);
+ APInt x_old(BitWidth, 1);
+ APInt x_new(BitWidth, 0);
+ APInt two(BitWidth, 2);
+
+ // Select a good starting value using binary logarithms.
+ for (;; i += 2, testy = testy.shl(2))
+ if (i >= nbits || this->ule(testy)) {
+ x_old = x_old.shl(i / 2);
+ break;
+ }
+
+ // Use the Babylonian method to arrive at the integer square root:
+ for (;;) {
+ x_new = (this->udiv(x_old) + x_old).udiv(two);
+ if (x_old.ule(x_new))
+ break;
+ x_old = x_new;
+ }
+
+ // Make sure we return the closest approximation
+ // NOTE: The rounding calculation below is correct. It will produce an
+ // off-by-one discrepancy with results from pari/gp. That discrepancy has been
+ // determined to be a rounding issue with pari/gp as it begins to use a
+ // floating point representation after 192 bits. There are no discrepancies
+ // between this algorithm and pari/gp for bit widths < 192 bits.
+ APInt square(x_old * x_old);
+ APInt nextSquare((x_old + 1) * (x_old +1));
+ if (this->ult(square))
+ return x_old;
+ else if (this->ule(nextSquare)) {
+ APInt midpoint((nextSquare - square).udiv(two));
+ APInt offset(*this - square);
+ if (offset.ult(midpoint))
+ return x_old;
+ else
+ return x_old + 1;
+ } else
+ llvm_unreachable("Error in APInt::sqrt computation");
+ return x_old + 1;
+}
+
+/// Computes the multiplicative inverse of this APInt for a given modulo. The
+/// iterative extended Euclidean algorithm is used to solve for this value,
+/// however we simplify it to speed up calculating only the inverse, and take
+/// advantage of div+rem calculations. We also use some tricks to avoid copying
+/// (potentially large) APInts around.
+APInt APInt::multiplicativeInverse(const APInt& modulo) const {
+ assert(ult(modulo) && "This APInt must be smaller than the modulo");
+
+ // Using the properties listed at the following web page (accessed 06/21/08):
+ // http://www.numbertheory.org/php/euclid.html
+ // (especially the properties numbered 3, 4 and 9) it can be proved that
+ // BitWidth bits suffice for all the computations in the algorithm implemented
+ // below. More precisely, this number of bits suffice if the multiplicative
+ // inverse exists, but may not suffice for the general extended Euclidean
+ // algorithm.
+
+ APInt r[2] = { modulo, *this };
+ APInt t[2] = { APInt(BitWidth, 0), APInt(BitWidth, 1) };
+ APInt q(BitWidth, 0);
+
+ unsigned i;
+ for (i = 0; r[i^1] != 0; i ^= 1) {
+ // An overview of the math without the confusing bit-flipping:
+ // q = r[i-2] / r[i-1]
+ // r[i] = r[i-2] % r[i-1]
+ // t[i] = t[i-2] - t[i-1] * q
+ udivrem(r[i], r[i^1], q, r[i]);
+ t[i] -= t[i^1] * q;
+ }
+
+ // If this APInt and the modulo are not coprime, there is no multiplicative
+ // inverse, so return 0. We check this by looking at the next-to-last
+ // remainder, which is the gcd(*this,modulo) as calculated by the Euclidean
+ // algorithm.
+ if (r[i] != 1)
+ return APInt(BitWidth, 0);
+
+ // The next-to-last t is the multiplicative inverse. However, we are
+ // interested in a positive inverse. Calcuate a positive one from a negative
+ // one if necessary. A simple addition of the modulo suffices because
+ // abs(t[i]) is known to be less than *this/2 (see the link above).
+ return t[i].isNegative() ? t[i] + modulo : t[i];
+}
+
+/// Calculate the magic numbers required to implement a signed integer division
+/// by a constant as a sequence of multiplies, adds and shifts. Requires that
+/// the divisor not be 0, 1, or -1. Taken from "Hacker's Delight", Henry S.
+/// Warren, Jr., chapter 10.
+APInt::ms APInt::magic() const {
+ const APInt& d = *this;
+ unsigned p;
+ APInt ad, anc, delta, q1, r1, q2, r2, t;
+ APInt signedMin = APInt::getSignedMinValue(d.getBitWidth());
+ struct ms mag;
+
+ ad = d.abs();
+ t = signedMin + (d.lshr(d.getBitWidth() - 1));
+ anc = t - 1 - t.urem(ad); // absolute value of nc
+ p = d.getBitWidth() - 1; // initialize p
+ q1 = signedMin.udiv(anc); // initialize q1 = 2p/abs(nc)
+ r1 = signedMin - q1*anc; // initialize r1 = rem(2p,abs(nc))
+ q2 = signedMin.udiv(ad); // initialize q2 = 2p/abs(d)
+ r2 = signedMin - q2*ad; // initialize r2 = rem(2p,abs(d))
+ do {
+ p = p + 1;
+ q1 = q1<<1; // update q1 = 2p/abs(nc)
+ r1 = r1<<1; // update r1 = rem(2p/abs(nc))
+ if (r1.uge(anc)) { // must be unsigned comparison
+ q1 = q1 + 1;
+ r1 = r1 - anc;
+ }
+ q2 = q2<<1; // update q2 = 2p/abs(d)
+ r2 = r2<<1; // update r2 = rem(2p/abs(d))
+ if (r2.uge(ad)) { // must be unsigned comparison
+ q2 = q2 + 1;
+ r2 = r2 - ad;
+ }
+ delta = ad - r2;
+ } while (q1.ule(delta) || (q1 == delta && r1 == 0));
+
+ mag.m = q2 + 1;
+ if (d.isNegative()) mag.m = -mag.m; // resulting magic number
+ mag.s = p - d.getBitWidth(); // resulting shift
+ return mag;
+}
+
+/// Calculate the magic numbers required to implement an unsigned integer
+/// division by a constant as a sequence of multiplies, adds and shifts.
+/// Requires that the divisor not be 0. Taken from "Hacker's Delight", Henry
+/// S. Warren, Jr., chapter 10.
+APInt::mu APInt::magicu() const {
+ const APInt& d = *this;
+ unsigned p;
+ APInt nc, delta, q1, r1, q2, r2;
+ struct mu magu;
+ magu.a = 0; // initialize "add" indicator
+ APInt allOnes = APInt::getAllOnesValue(d.getBitWidth());
+ APInt signedMin = APInt::getSignedMinValue(d.getBitWidth());
+ APInt signedMax = APInt::getSignedMaxValue(d.getBitWidth());
+
+ nc = allOnes - (-d).urem(d);
+ p = d.getBitWidth() - 1; // initialize p
+ q1 = signedMin.udiv(nc); // initialize q1 = 2p/nc
+ r1 = signedMin - q1*nc; // initialize r1 = rem(2p,nc)
+ q2 = signedMax.udiv(d); // initialize q2 = (2p-1)/d
+ r2 = signedMax - q2*d; // initialize r2 = rem((2p-1),d)
+ do {
+ p = p + 1;
+ if (r1.uge(nc - r1)) {
+ q1 = q1 + q1 + 1; // update q1
+ r1 = r1 + r1 - nc; // update r1
+ }
else {
- uint64_t *xwords = new uint64_t[xlen+1], *ywords = new uint64_t[ylen];
- assert(xwords && ywords && "Memory Allocation Failed!");
- memcpy(xwords, API.pVal, xlen * 8);
- xwords[xlen] = 0;
- memcpy(ywords, RHS.isSingleWord() ? &RHS.VAL : RHS.pVal, ylen * 8);
- if (unsigned nshift = 63 - (first - 1) % 64) {
- lshift(ywords, 0, ywords, ylen, nshift);
- unsigned xlentmp = xlen;
- xwords[xlen++] = lshift(xwords, 0, xwords, xlentmp, nshift);
+ q1 = q1+q1; // update q1
+ r1 = r1+r1; // update r1
+ }
+ if ((r2 + 1).uge(d - r2)) {
+ if (q2.uge(signedMax)) magu.a = 1;
+ q2 = q2+q2 + 1; // update q2
+ r2 = r2+r2 + 1 - d; // update r2
+ }
+ else {
+ if (q2.uge(signedMin)) magu.a = 1;
+ q2 = q2+q2; // update q2
+ r2 = r2+r2 + 1; // update r2
+ }
+ delta = d - 1 - r2;
+ } while (p < d.getBitWidth()*2 &&
+ (q1.ult(delta) || (q1 == delta && r1 == 0)));
+ magu.m = q2 + 1; // resulting magic number
+ magu.s = p - d.getBitWidth(); // resulting shift
+ return magu;
+}
+
+/// Implementation of Knuth's Algorithm D (Division of nonnegative integers)
+/// from "Art of Computer Programming, Volume 2", section 4.3.1, p. 272. The
+/// variables here have the same names as in the algorithm. Comments explain
+/// the algorithm and any deviation from it.
+static void KnuthDiv(unsigned *u, unsigned *v, unsigned *q, unsigned* r,
+ unsigned m, unsigned n) {
+ assert(u && "Must provide dividend");
+ assert(v && "Must provide divisor");
+ assert(q && "Must provide quotient");
+ assert(u != v && u != q && v != q && "Must us different memory");
+ assert(n>1 && "n must be > 1");
+
+ // Knuth uses the value b as the base of the number system. In our case b
+ // is 2^31 so we just set it to -1u.
+ uint64_t b = uint64_t(1) << 32;
+
+#if 0
+ DEBUG(dbgs() << "KnuthDiv: m=" << m << " n=" << n << '\n');
+ DEBUG(dbgs() << "KnuthDiv: original:");
+ DEBUG(for (int i = m+n; i >=0; i--) dbgs() << " " << u[i]);
+ DEBUG(dbgs() << " by");
+ DEBUG(for (int i = n; i >0; i--) dbgs() << " " << v[i-1]);
+ DEBUG(dbgs() << '\n');
+#endif
+ // D1. [Normalize.] Set d = b / (v[n-1] + 1) and multiply all the digits of
+ // u and v by d. Note that we have taken Knuth's advice here to use a power
+ // of 2 value for d such that d * v[n-1] >= b/2 (b is the base). A power of
+ // 2 allows us to shift instead of multiply and it is easy to determine the
+ // shift amount from the leading zeros. We are basically normalizing the u
+ // and v so that its high bits are shifted to the top of v's range without
+ // overflow. Note that this can require an extra word in u so that u must
+ // be of length m+n+1.
+ unsigned shift = CountLeadingZeros_32(v[n-1]);
+ unsigned v_carry = 0;
+ unsigned u_carry = 0;
+ if (shift) {
+ for (unsigned i = 0; i < m+n; ++i) {
+ unsigned u_tmp = u[i] >> (32 - shift);
+ u[i] = (u[i] << shift) | u_carry;
+ u_carry = u_tmp;
+ }
+ for (unsigned i = 0; i < n; ++i) {
+ unsigned v_tmp = v[i] >> (32 - shift);
+ v[i] = (v[i] << shift) | v_carry;
+ v_carry = v_tmp;
+ }
+ }
+ u[m+n] = u_carry;
+#if 0
+ DEBUG(dbgs() << "KnuthDiv: normal:");
+ DEBUG(for (int i = m+n; i >=0; i--) dbgs() << " " << u[i]);
+ DEBUG(dbgs() << " by");
+ DEBUG(for (int i = n; i >0; i--) dbgs() << " " << v[i-1]);
+ DEBUG(dbgs() << '\n');
+#endif
+
+ // D2. [Initialize j.] Set j to m. This is the loop counter over the places.
+ int j = m;
+ do {
+ DEBUG(dbgs() << "KnuthDiv: quotient digit #" << j << '\n');
+ // D3. [Calculate q'.].
+ // Set qp = (u[j+n]*b + u[j+n-1]) / v[n-1]. (qp=qprime=q')
+ // Set rp = (u[j+n]*b + u[j+n-1]) % v[n-1]. (rp=rprime=r')
+ // Now test if qp == b or qp*v[n-2] > b*rp + u[j+n-2]; if so, decrease
+ // qp by 1, inrease rp by v[n-1], and repeat this test if rp < b. The test
+ // on v[n-2] determines at high speed most of the cases in which the trial
+ // value qp is one too large, and it eliminates all cases where qp is two
+ // too large.
+ uint64_t dividend = ((uint64_t(u[j+n]) << 32) + u[j+n-1]);
+ DEBUG(dbgs() << "KnuthDiv: dividend == " << dividend << '\n');
+ uint64_t qp = dividend / v[n-1];
+ uint64_t rp = dividend % v[n-1];
+ if (qp == b || qp*v[n-2] > b*rp + u[j+n-2]) {
+ qp--;
+ rp += v[n-1];
+ if (rp < b && (qp == b || qp*v[n-2] > b*rp + u[j+n-2]))
+ qp--;
+ }
+ DEBUG(dbgs() << "KnuthDiv: qp == " << qp << ", rp == " << rp << '\n');
+
+ // D4. [Multiply and subtract.] Replace (u[j+n]u[j+n-1]...u[j]) with
+ // (u[j+n]u[j+n-1]..u[j]) - qp * (v[n-1]...v[1]v[0]). This computation
+ // consists of a simple multiplication by a one-place number, combined with
+ // a subtraction.
+ bool isNeg = false;
+ for (unsigned i = 0; i < n; ++i) {
+ uint64_t u_tmp = uint64_t(u[j+i]) | (uint64_t(u[j+i+1]) << 32);
+ uint64_t subtrahend = uint64_t(qp) * uint64_t(v[i]);
+ bool borrow = subtrahend > u_tmp;
+ DEBUG(dbgs() << "KnuthDiv: u_tmp == " << u_tmp
+ << ", subtrahend == " << subtrahend
+ << ", borrow = " << borrow << '\n');
+
+ uint64_t result = u_tmp - subtrahend;
+ unsigned k = j + i;
+ u[k++] = (unsigned)(result & (b-1)); // subtract low word
+ u[k++] = (unsigned)(result >> 32); // subtract high word
+ while (borrow && k <= m+n) { // deal with borrow to the left
+ borrow = u[k] == 0;
+ u[k]--;
+ k++;
+ }
+ isNeg |= borrow;
+ DEBUG(dbgs() << "KnuthDiv: u[j+i] == " << u[j+i] << ", u[j+i+1] == " <<
+ u[j+i+1] << '\n');
+ }
+ DEBUG(dbgs() << "KnuthDiv: after subtraction:");
+ DEBUG(for (int i = m+n; i >=0; i--) dbgs() << " " << u[i]);
+ DEBUG(dbgs() << '\n');
+ // The digits (u[j+n]...u[j]) should be kept positive; if the result of
+ // this step is actually negative, (u[j+n]...u[j]) should be left as the
+ // true value plus b**(n+1), namely as the b's complement of
+ // the true value, and a "borrow" to the left should be remembered.
+ //
+ if (isNeg) {
+ bool carry = true; // true because b's complement is "complement + 1"
+ for (unsigned i = 0; i <= m+n; ++i) {
+ u[i] = ~u[i] + carry; // b's complement
+ carry = carry && u[i] == 0;
}
- div((unsigned*)xwords, xlen*2-1, (unsigned*)ywords, ylen*2);
- memset(API.pVal, 0, API.getNumWords() * 8);
- memcpy(API.pVal, xwords + ylen, (xlen - ylen) * 8);
- delete[] xwords;
- delete[] ywords;
}
+ DEBUG(dbgs() << "KnuthDiv: after complement:");
+ DEBUG(for (int i = m+n; i >=0; i--) dbgs() << " " << u[i]);
+ DEBUG(dbgs() << '\n');
+
+ // D5. [Test remainder.] Set q[j] = qp. If the result of step D4 was
+ // negative, go to step D6; otherwise go on to step D7.
+ q[j] = (unsigned)qp;
+ if (isNeg) {
+ // D6. [Add back]. The probability that this step is necessary is very
+ // small, on the order of only 2/b. Make sure that test data accounts for
+ // this possibility. Decrease q[j] by 1
+ q[j]--;
+ // and add (0v[n-1]...v[1]v[0]) to (u[j+n]u[j+n-1]...u[j+1]u[j]).
+ // A carry will occur to the left of u[j+n], and it should be ignored
+ // since it cancels with the borrow that occurred in D4.
+ bool carry = false;
+ for (unsigned i = 0; i < n; i++) {
+ unsigned limit = std::min(u[j+i],v[i]);
+ u[j+i] += v[i] + carry;
+ carry = u[j+i] < limit || (carry && u[j+i] == limit);
+ }
+ u[j+n] += carry;
+ }
+ DEBUG(dbgs() << "KnuthDiv: after correction:");
+ DEBUG(for (int i = m+n; i >=0; i--) dbgs() <<" " << u[i]);
+ DEBUG(dbgs() << "\nKnuthDiv: digit result = " << q[j] << '\n');
+
+ // D7. [Loop on j.] Decrease j by one. Now if j >= 0, go back to D3.
+ } while (--j >= 0);
+
+ DEBUG(dbgs() << "KnuthDiv: quotient:");
+ DEBUG(for (int i = m; i >=0; i--) dbgs() <<" " << q[i]);
+ DEBUG(dbgs() << '\n');
+
+ // D8. [Unnormalize]. Now q[...] is the desired quotient, and the desired
+ // remainder may be obtained by dividing u[...] by d. If r is non-null we
+ // compute the remainder (urem uses this).
+ if (r) {
+ // The value d is expressed by the "shift" value above since we avoided
+ // multiplication by d by using a shift left. So, all we have to do is
+ // shift right here. In order to mak
+ if (shift) {
+ unsigned carry = 0;
+ DEBUG(dbgs() << "KnuthDiv: remainder:");
+ for (int i = n-1; i >= 0; i--) {
+ r[i] = (u[i] >> shift) | carry;
+ carry = u[i] << (32 - shift);
+ DEBUG(dbgs() << " " << r[i]);
+ }
+ } else {
+ for (int i = n-1; i >= 0; i--) {
+ r[i] = u[i];
+ DEBUG(dbgs() << " " << r[i]);
+ }
+ }
+ DEBUG(dbgs() << '\n');
}
- return API;
+#if 0
+ DEBUG(dbgs() << '\n');
+#endif
+}
+
+void APInt::divide(const APInt LHS, unsigned lhsWords,
+ const APInt &RHS, unsigned rhsWords,
+ APInt *Quotient, APInt *Remainder)
+{
+ assert(lhsWords >= rhsWords && "Fractional result");
+
+ // First, compose the values into an array of 32-bit words instead of
+ // 64-bit words. This is a necessity of both the "short division" algorithm
+ // and the Knuth "classical algorithm" which requires there to be native
+ // operations for +, -, and * on an m bit value with an m*2 bit result. We
+ // can't use 64-bit operands here because we don't have native results of
+ // 128-bits. Furthermore, casting the 64-bit values to 32-bit values won't
+ // work on large-endian machines.
+ uint64_t mask = ~0ull >> (sizeof(unsigned)*CHAR_BIT);
+ unsigned n = rhsWords * 2;
+ unsigned m = (lhsWords * 2) - n;
+
+ // Allocate space for the temporary values we need either on the stack, if
+ // it will fit, or on the heap if it won't.
+ unsigned SPACE[128];
+ unsigned *U = 0;
+ unsigned *V = 0;
+ unsigned *Q = 0;
+ unsigned *R = 0;
+ if ((Remainder?4:3)*n+2*m+1 <= 128) {
+ U = &SPACE[0];
+ V = &SPACE[m+n+1];
+ Q = &SPACE[(m+n+1) + n];
+ if (Remainder)
+ R = &SPACE[(m+n+1) + n + (m+n)];
+ } else {
+ U = new unsigned[m + n + 1];
+ V = new unsigned[n];
+ Q = new unsigned[m+n];
+ if (Remainder)
+ R = new unsigned[n];
+ }
+
+ // Initialize the dividend
+ memset(U, 0, (m+n+1)*sizeof(unsigned));
+ for (unsigned i = 0; i < lhsWords; ++i) {
+ uint64_t tmp = (LHS.getNumWords() == 1 ? LHS.VAL : LHS.pVal[i]);
+ U[i * 2] = (unsigned)(tmp & mask);
+ U[i * 2 + 1] = (unsigned)(tmp >> (sizeof(unsigned)*CHAR_BIT));
+ }
+ U[m+n] = 0; // this extra word is for "spill" in the Knuth algorithm.
+
+ // Initialize the divisor
+ memset(V, 0, (n)*sizeof(unsigned));
+ for (unsigned i = 0; i < rhsWords; ++i) {
+ uint64_t tmp = (RHS.getNumWords() == 1 ? RHS.VAL : RHS.pVal[i]);
+ V[i * 2] = (unsigned)(tmp & mask);
+ V[i * 2 + 1] = (unsigned)(tmp >> (sizeof(unsigned)*CHAR_BIT));
+ }
+
+ // initialize the quotient and remainder
+ memset(Q, 0, (m+n) * sizeof(unsigned));
+ if (Remainder)
+ memset(R, 0, n * sizeof(unsigned));
+
+ // Now, adjust m and n for the Knuth division. n is the number of words in
+ // the divisor. m is the number of words by which the dividend exceeds the
+ // divisor (i.e. m+n is the length of the dividend). These sizes must not
+ // contain any zero words or the Knuth algorithm fails.
+ for (unsigned i = n; i > 0 && V[i-1] == 0; i--) {
+ n--;
+ m++;
+ }
+ for (unsigned i = m+n; i > 0 && U[i-1] == 0; i--)
+ m--;
+
+ // If we're left with only a single word for the divisor, Knuth doesn't work
+ // so we implement the short division algorithm here. This is much simpler
+ // and faster because we are certain that we can divide a 64-bit quantity
+ // by a 32-bit quantity at hardware speed and short division is simply a
+ // series of such operations. This is just like doing short division but we
+ // are using base 2^32 instead of base 10.
+ assert(n != 0 && "Divide by zero?");
+ if (n == 1) {
+ unsigned divisor = V[0];
+ unsigned remainder = 0;
+ for (int i = m+n-1; i >= 0; i--) {
+ uint64_t partial_dividend = uint64_t(remainder) << 32 | U[i];
+ if (partial_dividend == 0) {
+ Q[i] = 0;
+ remainder = 0;
+ } else if (partial_dividend < divisor) {
+ Q[i] = 0;
+ remainder = (unsigned)partial_dividend;
+ } else if (partial_dividend == divisor) {
+ Q[i] = 1;
+ remainder = 0;
+ } else {
+ Q[i] = (unsigned)(partial_dividend / divisor);
+ remainder = (unsigned)(partial_dividend - (Q[i] * divisor));
+ }
+ }
+ if (R)
+ R[0] = remainder;
+ } else {
+ // Now we're ready to invoke the Knuth classical divide algorithm. In this
+ // case n > 1.
+ KnuthDiv(U, V, Q, R, m, n);
+ }
+
+ // If the caller wants the quotient
+ if (Quotient) {
+ // Set up the Quotient value's memory.
+ if (Quotient->BitWidth != LHS.BitWidth) {
+ if (Quotient->isSingleWord())
+ Quotient->VAL = 0;
+ else
+ delete [] Quotient->pVal;
+ Quotient->BitWidth = LHS.BitWidth;
+ if (!Quotient->isSingleWord())
+ Quotient->pVal = getClearedMemory(Quotient->getNumWords());
+ } else
+ Quotient->clear();
+
+ // The quotient is in Q. Reconstitute the quotient into Quotient's low
+ // order words.
+ if (lhsWords == 1) {
+ uint64_t tmp =
+ uint64_t(Q[0]) | (uint64_t(Q[1]) << (APINT_BITS_PER_WORD / 2));
+ if (Quotient->isSingleWord())
+ Quotient->VAL = tmp;
+ else
+ Quotient->pVal[0] = tmp;
+ } else {
+ assert(!Quotient->isSingleWord() && "Quotient APInt not large enough");
+ for (unsigned i = 0; i < lhsWords; ++i)
+ Quotient->pVal[i] =
+ uint64_t(Q[i*2]) | (uint64_t(Q[i*2+1]) << (APINT_BITS_PER_WORD / 2));
+ }
+ }
+
+ // If the caller wants the remainder
+ if (Remainder) {
+ // Set up the Remainder value's memory.
+ if (Remainder->BitWidth != RHS.BitWidth) {
+ if (Remainder->isSingleWord())
+ Remainder->VAL = 0;
+ else
+ delete [] Remainder->pVal;
+ Remainder->BitWidth = RHS.BitWidth;
+ if (!Remainder->isSingleWord())
+ Remainder->pVal = getClearedMemory(Remainder->getNumWords());
+ } else
+ Remainder->clear();
+
+ // The remainder is in R. Reconstitute the remainder into Remainder's low
+ // order words.
+ if (rhsWords == 1) {
+ uint64_t tmp =
+ uint64_t(R[0]) | (uint64_t(R[1]) << (APINT_BITS_PER_WORD / 2));
+ if (Remainder->isSingleWord())
+ Remainder->VAL = tmp;
+ else
+ Remainder->pVal[0] = tmp;
+ } else {
+ assert(!Remainder->isSingleWord() && "Remainder APInt not large enough");
+ for (unsigned i = 0; i < rhsWords; ++i)
+ Remainder->pVal[i] =
+ uint64_t(R[i*2]) | (uint64_t(R[i*2+1]) << (APINT_BITS_PER_WORD / 2));
+ }
+ }
+
+ // Clean up the memory we allocated.
+ if (U != &SPACE[0]) {
+ delete [] U;
+ delete [] V;
+ delete [] Q;
+ delete [] R;
+ }
+}
+
+APInt APInt::udiv(const APInt& RHS) const {
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+
+ // First, deal with the easy case
+ if (isSingleWord()) {
+ assert(RHS.VAL != 0 && "Divide by zero?");
+ return APInt(BitWidth, VAL / RHS.VAL);
+ }
+
+ // Get some facts about the LHS and RHS number of bits and words
+ unsigned rhsBits = RHS.getActiveBits();
+ unsigned rhsWords = !rhsBits ? 0 : (APInt::whichWord(rhsBits - 1) + 1);
+ assert(rhsWords && "Divided by zero???");
+ unsigned lhsBits = this->getActiveBits();
+ unsigned lhsWords = !lhsBits ? 0 : (APInt::whichWord(lhsBits - 1) + 1);
+
+ // Deal with some degenerate cases
+ if (!lhsWords)
+ // 0 / X ===> 0
+ return APInt(BitWidth, 0);
+ else if (lhsWords < rhsWords || this->ult(RHS)) {
+ // X / Y ===> 0, iff X < Y
+ return APInt(BitWidth, 0);
+ } else if (*this == RHS) {
+ // X / X ===> 1
+ return APInt(BitWidth, 1);
+ } else if (lhsWords == 1 && rhsWords == 1) {
+ // All high words are zero, just use native divide
+ return APInt(BitWidth, this->pVal[0] / RHS.pVal[0]);
+ }
+
+ // We have to compute it the hard way. Invoke the Knuth divide algorithm.
+ APInt Quotient(1,0); // to hold result.
+ divide(*this, lhsWords, RHS, rhsWords, &Quotient, 0);
+ return Quotient;
}
-/// Unsigned remainder operation on APInt.
-/// @brief Function for unsigned remainder operation.
APInt APInt::urem(const APInt& RHS) const {
- APInt API(*this);
- unsigned first = RHS.getNumWords() * APInt::APINT_BITS_PER_WORD -
- RHS.CountLeadingZeros();
- unsigned ylen = !first ? 0 : APInt::whichWord(first - 1) + 1;
- assert(ylen && "Performing remainder operation by zero ???");
- if (API.isSingleWord()) {
- API.VAL = RHS.isSingleWord() ? (API.VAL % RHS.VAL) :
- (ylen > 1 ? API.VAL : API.VAL % RHS.pVal[0]);
+ assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
+ if (isSingleWord()) {
+ assert(RHS.VAL != 0 && "Remainder by zero?");
+ return APInt(BitWidth, VAL % RHS.VAL);
+ }
+
+ // Get some facts about the LHS
+ unsigned lhsBits = getActiveBits();
+ unsigned lhsWords = !lhsBits ? 0 : (whichWord(lhsBits - 1) + 1);
+
+ // Get some facts about the RHS
+ unsigned rhsBits = RHS.getActiveBits();
+ unsigned rhsWords = !rhsBits ? 0 : (APInt::whichWord(rhsBits - 1) + 1);
+ assert(rhsWords && "Performing remainder operation by zero ???");
+
+ // Check the degenerate cases
+ if (lhsWords == 0) {
+ // 0 % Y ===> 0
+ return APInt(BitWidth, 0);
+ } else if (lhsWords < rhsWords || this->ult(RHS)) {
+ // X % Y ===> X, iff X < Y
+ return *this;
+ } else if (*this == RHS) {
+ // X % X == 0;
+ return APInt(BitWidth, 0);
+ } else if (lhsWords == 1) {
+ // All high words are zero, just use native remainder
+ return APInt(BitWidth, pVal[0] % RHS.pVal[0]);
+ }
+
+ // We have to compute it the hard way. Invoke the Knuth divide algorithm.
+ APInt Remainder(1,0);
+ divide(*this, lhsWords, RHS, rhsWords, 0, &Remainder);
+ return Remainder;
+}
+
+void APInt::udivrem(const APInt &LHS, const APInt &RHS,
+ APInt &Quotient, APInt &Remainder) {
+ // Get some size facts about the dividend and divisor
+ unsigned lhsBits = LHS.getActiveBits();
+ unsigned lhsWords = !lhsBits ? 0 : (APInt::whichWord(lhsBits - 1) + 1);
+ unsigned rhsBits = RHS.getActiveBits();
+ unsigned rhsWords = !rhsBits ? 0 : (APInt::whichWord(rhsBits - 1) + 1);
+
+ // Check the degenerate cases
+ if (lhsWords == 0) {
+ Quotient = 0; // 0 / Y ===> 0
+ Remainder = 0; // 0 % Y ===> 0
+ return;
+ }
+
+ if (lhsWords < rhsWords || LHS.ult(RHS)) {
+ Remainder = LHS; // X % Y ===> X, iff X < Y
+ Quotient = 0; // X / Y ===> 0, iff X < Y
+ return;
+ }
+
+ if (LHS == RHS) {
+ Quotient = 1; // X / X ===> 1
+ Remainder = 0; // X % X ===> 0;
+ return;
+ }
+
+ if (lhsWords == 1 && rhsWords == 1) {
+ // There is only one word to consider so use the native versions.
+ uint64_t lhsValue = LHS.isSingleWord() ? LHS.VAL : LHS.pVal[0];
+ uint64_t rhsValue = RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
+ Quotient = APInt(LHS.getBitWidth(), lhsValue / rhsValue);
+ Remainder = APInt(LHS.getBitWidth(), lhsValue % rhsValue);
+ return;
+ }
+
+ // Okay, lets do it the long way
+ divide(LHS, lhsWords, RHS, rhsWords, &Quotient, &Remainder);
+}
+
+void APInt::fromString(unsigned numbits, StringRef str, uint8_t radix) {
+ // Check our assumptions here
+ assert(!str.empty() && "Invalid string length");
+ assert((radix == 10 || radix == 8 || radix == 16 || radix == 2) &&
+ "Radix should be 2, 8, 10, or 16!");
+
+ StringRef::iterator p = str.begin();
+ size_t slen = str.size();
+ bool isNeg = *p == '-';
+ if (*p == '-' || *p == '+') {
+ p++;
+ slen--;
+ assert(slen && "String is only a sign, needs a value.");
+ }
+ assert((slen <= numbits || radix != 2) && "Insufficient bit width");
+ assert(((slen-1)*3 <= numbits || radix != 8) && "Insufficient bit width");
+ assert(((slen-1)*4 <= numbits || radix != 16) && "Insufficient bit width");
+ assert((((slen-1)*64)/22 <= numbits || radix != 10) &&
+ "Insufficient bit width");
+
+ // Allocate memory
+ if (!isSingleWord())
+ pVal = getClearedMemory(getNumWords());
+
+ // Figure out if we can shift instead of multiply
+ unsigned shift = (radix == 16 ? 4 : radix == 8 ? 3 : radix == 2 ? 1 : 0);
+
+ // Set up an APInt for the digit to add outside the loop so we don't
+ // constantly construct/destruct it.
+ APInt apdigit(getBitWidth(), 0);
+ APInt apradix(getBitWidth(), radix);
+
+ // Enter digit traversal loop
+ for (StringRef::iterator e = str.end(); p != e; ++p) {
+ unsigned digit = getDigit(*p, radix);
+ assert(digit < radix && "Invalid character in digit string");
+
+ // Shift or multiply the value by the radix
+ if (slen > 1) {
+ if (shift)
+ *this <<= shift;
+ else
+ *this *= apradix;
+ }
+
+ // Add in the digit we just interpreted
+ if (apdigit.isSingleWord())
+ apdigit.VAL = digit;
+ else
+ apdigit.pVal[0] = digit;
+ *this += apdigit;
+ }
+ // If its negative, put it in two's complement form
+ if (isNeg) {
+ (*this)--;
+ this->flip();
+ }
+}
+
+void APInt::toString(SmallVectorImpl<char> &Str, unsigned Radix,
+ bool Signed) const {
+ assert((Radix == 10 || Radix == 8 || Radix == 16 || Radix == 2) &&
+ "Radix should be 2, 8, 10, or 16!");
+
+ // First, check for a zero value and just short circuit the logic below.
+ if (*this == 0) {
+ Str.push_back('0');
+ return;
+ }
+
+ static const char Digits[] = "0123456789ABCDEF";
+
+ if (isSingleWord()) {
+ char Buffer[65];
+ char *BufPtr = Buffer+65;
+
+ uint64_t N;
+ if (Signed) {
+ int64_t I = getSExtValue();
+ if (I < 0) {
+ Str.push_back('-');
+ I = -I;
+ }
+ N = I;
+ } else {
+ N = getZExtValue();
+ }
+
+ while (N) {
+ *--BufPtr = Digits[N % Radix];
+ N /= Radix;
+ }
+ Str.append(BufPtr, Buffer+65);
+ return;
+ }
+
+ APInt Tmp(*this);
+
+ if (Signed && isNegative()) {
+ // They want to print the signed version and it is a negative value
+ // Flip the bits and add one to turn it into the equivalent positive
+ // value and put a '-' in the result.
+ Tmp.flip();
+ Tmp++;
+ Str.push_back('-');
+ }
+
+ // We insert the digits backward, then reverse them to get the right order.
+ unsigned StartDig = Str.size();
+
+ // For the 2, 8 and 16 bit cases, we can just shift instead of divide
+ // because the number of bits per digit (1, 3 and 4 respectively) divides
+ // equaly. We just shift until the value is zero.
+ if (Radix != 10) {
+ // Just shift tmp right for each digit width until it becomes zero
+ unsigned ShiftAmt = (Radix == 16 ? 4 : (Radix == 8 ? 3 : 1));
+ unsigned MaskAmt = Radix - 1;
+
+ while (Tmp != 0) {
+ unsigned Digit = unsigned(Tmp.getRawData()[0]) & MaskAmt;
+ Str.push_back(Digits[Digit]);
+ Tmp = Tmp.lshr(ShiftAmt);
+ }
} else {
- unsigned first2 = API.getNumWords() * APInt::APINT_BITS_PER_WORD -
- API.CountLeadingZeros();
- unsigned xlen = !first2 ? 0 : API.whichWord(first2 - 1) + 1;
- if (!xlen || API < RHS)
- return API;
- else if (API == RHS)
- memset(API.pVal, 0, API.getNumWords() * 8);
- else if (xlen == 1)
- API.pVal[0] %= RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
- else {
- uint64_t *xwords = new uint64_t[xlen+1], *ywords = new uint64_t[ylen];
- assert(xwords && ywords && "Memory Allocation Failed!");
- memcpy(xwords, API.pVal, xlen * 8);
- xwords[xlen] = 0;
- memcpy(ywords, RHS.isSingleWord() ? &RHS.VAL : RHS.pVal, ylen * 8);
- unsigned nshift = 63 - (first - 1) % 64;
- if (nshift) {
- lshift(ywords, 0, ywords, ylen, nshift);
- unsigned xlentmp = xlen;
- xwords[xlen++] = lshift(xwords, 0, xwords, xlentmp, nshift);
+ APInt divisor(4, 10);
+ while (Tmp != 0) {
+ APInt APdigit(1, 0);
+ APInt tmp2(Tmp.getBitWidth(), 0);
+ divide(Tmp, Tmp.getNumWords(), divisor, divisor.getNumWords(), &tmp2,
+ &APdigit);
+ unsigned Digit = (unsigned)APdigit.getZExtValue();
+ assert(Digit < Radix && "divide failed");
+ Str.push_back(Digits[Digit]);
+ Tmp = tmp2;
+ }
+ }
+
+ // Reverse the digits before returning.
+ std::reverse(Str.begin()+StartDig, Str.end());
+}
+
+/// toString - This returns the APInt as a std::string. Note that this is an
+/// inefficient method. It is better to pass in a SmallVector/SmallString
+/// to the methods above.
+std::string APInt::toString(unsigned Radix = 10, bool Signed = true) const {
+ SmallString<40> S;
+ toString(S, Radix, Signed);
+ return S.str();
+}
+
+
+void APInt::dump() const {
+ SmallString<40> S, U;
+ this->toStringUnsigned(U);
+ this->toStringSigned(S);
+ dbgs() << "APInt(" << BitWidth << "b, "
+ << U.str() << "u " << S.str() << "s)";
+}
+
+void APInt::print(raw_ostream &OS, bool isSigned) const {
+ SmallString<40> S;
+ this->toString(S, 10, isSigned);
+ OS << S.str();
+}
+
+// This implements a variety of operations on a representation of
+// arbitrary precision, two's-complement, bignum integer values.
+
+// Assumed by lowHalf, highHalf, partMSB and partLSB. A fairly safe
+// and unrestricting assumption.
+#define COMPILE_TIME_ASSERT(cond) extern int CTAssert[(cond) ? 1 : -1]
+COMPILE_TIME_ASSERT(integerPartWidth % 2 == 0);
+
+/* Some handy functions local to this file. */
+namespace {
+
+ /* Returns the integer part with the least significant BITS set.
+ BITS cannot be zero. */
+ static inline integerPart
+ lowBitMask(unsigned int bits)
+ {
+ assert(bits != 0 && bits <= integerPartWidth);
+
+ return ~(integerPart) 0 >> (integerPartWidth - bits);
+ }
+
+ /* Returns the value of the lower half of PART. */
+ static inline integerPart
+ lowHalf(integerPart part)
+ {
+ return part & lowBitMask(integerPartWidth / 2);
+ }
+
+ /* Returns the value of the upper half of PART. */
+ static inline integerPart
+ highHalf(integerPart part)
+ {
+ return part >> (integerPartWidth / 2);
+ }
+
+ /* Returns the bit number of the most significant set bit of a part.
+ If the input number has no bits set -1U is returned. */
+ static unsigned int
+ partMSB(integerPart value)
+ {
+ unsigned int n, msb;
+
+ if (value == 0)
+ return -1U;
+
+ n = integerPartWidth / 2;
+
+ msb = 0;
+ do {
+ if (value >> n) {
+ value >>= n;
+ msb += n;
+ }
+
+ n >>= 1;
+ } while (n);
+
+ return msb;
+ }
+
+ /* Returns the bit number of the least significant set bit of a
+ part. If the input number has no bits set -1U is returned. */
+ static unsigned int
+ partLSB(integerPart value)
+ {
+ unsigned int n, lsb;
+
+ if (value == 0)
+ return -1U;
+
+ lsb = integerPartWidth - 1;
+ n = integerPartWidth / 2;
+
+ do {
+ if (value << n) {
+ value <<= n;
+ lsb -= n;
+ }
+
+ n >>= 1;
+ } while (n);
+
+ return lsb;
+ }
+}
+
+/* Sets the least significant part of a bignum to the input value, and
+ zeroes out higher parts. */
+void
+APInt::tcSet(integerPart *dst, integerPart part, unsigned int parts)
+{
+ unsigned int i;
+
+ assert(parts > 0);
+
+ dst[0] = part;
+ for (i = 1; i < parts; i++)
+ dst[i] = 0;
+}
+
+/* Assign one bignum to another. */
+void
+APInt::tcAssign(integerPart *dst, const integerPart *src, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ dst[i] = src[i];
+}
+
+/* Returns true if a bignum is zero, false otherwise. */
+bool
+APInt::tcIsZero(const integerPart *src, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ if (src[i])
+ return false;
+
+ return true;
+}
+
+/* Extract the given bit of a bignum; returns 0 or 1. */
+int
+APInt::tcExtractBit(const integerPart *parts, unsigned int bit)
+{
+ return (parts[bit / integerPartWidth] &
+ ((integerPart) 1 << bit % integerPartWidth)) != 0;
+}
+
+/* Set the given bit of a bignum. */
+void
+APInt::tcSetBit(integerPart *parts, unsigned int bit)
+{
+ parts[bit / integerPartWidth] |= (integerPart) 1 << (bit % integerPartWidth);
+}
+
+/* Clears the given bit of a bignum. */
+void
+APInt::tcClearBit(integerPart *parts, unsigned int bit)
+{
+ parts[bit / integerPartWidth] &=
+ ~((integerPart) 1 << (bit % integerPartWidth));
+}
+
+/* Returns the bit number of the least significant set bit of a
+ number. If the input number has no bits set -1U is returned. */
+unsigned int
+APInt::tcLSB(const integerPart *parts, unsigned int n)
+{
+ unsigned int i, lsb;
+
+ for (i = 0; i < n; i++) {
+ if (parts[i] != 0) {
+ lsb = partLSB(parts[i]);
+
+ return lsb + i * integerPartWidth;
}
- div((unsigned*)xwords, xlen*2-1, (unsigned*)ywords, ylen*2);
- memset(API.pVal, 0, API.getNumWords() * 8);
- for (unsigned i = 0; i < ylen-1; ++i)
- API.pVal[i] = (xwords[i] >> nshift) | (xwords[i+1] << (64 - nshift));
- API.pVal[ylen-1] = xwords[ylen-1] >> nshift;
- delete[] xwords;
- delete[] ywords;
+ }
+
+ return -1U;
+}
+
+/* Returns the bit number of the most significant set bit of a number.
+ If the input number has no bits set -1U is returned. */
+unsigned int
+APInt::tcMSB(const integerPart *parts, unsigned int n)
+{
+ unsigned int msb;
+
+ do {
+ --n;
+
+ if (parts[n] != 0) {
+ msb = partMSB(parts[n]);
+
+ return msb + n * integerPartWidth;
}
+ } while (n);
+
+ return -1U;
+}
+
+/* Copy the bit vector of width srcBITS from SRC, starting at bit
+ srcLSB, to DST, of dstCOUNT parts, such that the bit srcLSB becomes
+ the least significant bit of DST. All high bits above srcBITS in
+ DST are zero-filled. */
+void
+APInt::tcExtract(integerPart *dst, unsigned int dstCount,const integerPart *src,
+ unsigned int srcBits, unsigned int srcLSB)
+{
+ unsigned int firstSrcPart, dstParts, shift, n;
+
+ dstParts = (srcBits + integerPartWidth - 1) / integerPartWidth;
+ assert(dstParts <= dstCount);
+
+ firstSrcPart = srcLSB / integerPartWidth;
+ tcAssign (dst, src + firstSrcPart, dstParts);
+
+ shift = srcLSB % integerPartWidth;
+ tcShiftRight (dst, dstParts, shift);
+
+ /* We now have (dstParts * integerPartWidth - shift) bits from SRC
+ in DST. If this is less that srcBits, append the rest, else
+ clear the high bits. */
+ n = dstParts * integerPartWidth - shift;
+ if (n < srcBits) {
+ integerPart mask = lowBitMask (srcBits - n);
+ dst[dstParts - 1] |= ((src[firstSrcPart + dstParts] & mask)
+ << n % integerPartWidth);
+ } else if (n > srcBits) {
+ if (srcBits % integerPartWidth)
+ dst[dstParts - 1] &= lowBitMask (srcBits % integerPartWidth);
}
- return API;
+
+ /* Clear high parts. */
+ while (dstParts < dstCount)
+ dst[dstParts++] = 0;
}
-#endif
+/* DST += RHS + C where C is zero or one. Returns the carry flag. */
+integerPart
+APInt::tcAdd(integerPart *dst, const integerPart *rhs,
+ integerPart c, unsigned int parts)
+{
+ unsigned int i;
+
+ assert(c <= 1);
+
+ for (i = 0; i < parts; i++) {
+ integerPart l;
+
+ l = dst[i];
+ if (c) {
+ dst[i] += rhs[i] + 1;
+ c = (dst[i] <= l);
+ } else {
+ dst[i] += rhs[i];
+ c = (dst[i] < l);
+ }
+ }
+
+ return c;
+}
+
+/* DST -= RHS + C where C is zero or one. Returns the carry flag. */
+integerPart
+APInt::tcSubtract(integerPart *dst, const integerPart *rhs,
+ integerPart c, unsigned int parts)
+{
+ unsigned int i;
+
+ assert(c <= 1);
+
+ for (i = 0; i < parts; i++) {
+ integerPart l;
+
+ l = dst[i];
+ if (c) {
+ dst[i] -= rhs[i] + 1;
+ c = (dst[i] >= l);
+ } else {
+ dst[i] -= rhs[i];
+ c = (dst[i] > l);
+ }
+ }
+
+ return c;
+}
+
+/* Negate a bignum in-place. */
+void
+APInt::tcNegate(integerPart *dst, unsigned int parts)
+{
+ tcComplement(dst, parts);
+ tcIncrement(dst, parts);
+}
+
+/* DST += SRC * MULTIPLIER + CARRY if add is true
+ DST = SRC * MULTIPLIER + CARRY if add is false
+
+ Requires 0 <= DSTPARTS <= SRCPARTS + 1. If DST overlaps SRC
+ they must start at the same point, i.e. DST == SRC.
+
+ If DSTPARTS == SRCPARTS + 1 no overflow occurs and zero is
+ returned. Otherwise DST is filled with the least significant
+ DSTPARTS parts of the result, and if all of the omitted higher
+ parts were zero return zero, otherwise overflow occurred and
+ return one. */
+int
+APInt::tcMultiplyPart(integerPart *dst, const integerPart *src,
+ integerPart multiplier, integerPart carry,
+ unsigned int srcParts, unsigned int dstParts,
+ bool add)
+{
+ unsigned int i, n;
+
+ /* Otherwise our writes of DST kill our later reads of SRC. */
+ assert(dst <= src || dst >= src + srcParts);
+ assert(dstParts <= srcParts + 1);
+
+ /* N loops; minimum of dstParts and srcParts. */
+ n = dstParts < srcParts ? dstParts: srcParts;
+
+ for (i = 0; i < n; i++) {
+ integerPart low, mid, high, srcPart;
+
+ /* [ LOW, HIGH ] = MULTIPLIER * SRC[i] + DST[i] + CARRY.
+
+ This cannot overflow, because
+
+ (n - 1) * (n - 1) + 2 (n - 1) = (n - 1) * (n + 1)
+
+ which is less than n^2. */
+
+ srcPart = src[i];
+
+ if (multiplier == 0 || srcPart == 0) {
+ low = carry;
+ high = 0;
+ } else {
+ low = lowHalf(srcPart) * lowHalf(multiplier);
+ high = highHalf(srcPart) * highHalf(multiplier);
+
+ mid = lowHalf(srcPart) * highHalf(multiplier);
+ high += highHalf(mid);
+ mid <<= integerPartWidth / 2;
+ if (low + mid < low)
+ high++;
+ low += mid;
+
+ mid = highHalf(srcPart) * lowHalf(multiplier);
+ high += highHalf(mid);
+ mid <<= integerPartWidth / 2;
+ if (low + mid < low)
+ high++;
+ low += mid;
+
+ /* Now add carry. */
+ if (low + carry < low)
+ high++;
+ low += carry;
+ }
+
+ if (add) {
+ /* And now DST[i], and store the new low part there. */
+ if (low + dst[i] < low)
+ high++;
+ dst[i] += low;
+ } else
+ dst[i] = low;
+
+ carry = high;
+ }
+
+ if (i < dstParts) {
+ /* Full multiplication, there is no overflow. */
+ assert(i + 1 == dstParts);
+ dst[i] = carry;
+ return 0;
+ } else {
+ /* We overflowed if there is carry. */
+ if (carry)
+ return 1;
+
+ /* We would overflow if any significant unwritten parts would be
+ non-zero. This is true if any remaining src parts are non-zero
+ and the multiplier is non-zero. */
+ if (multiplier)
+ for (; i < srcParts; i++)
+ if (src[i])
+ return 1;
+
+ /* We fitted in the narrow destination. */
+ return 0;
+ }
+}
+
+/* DST = LHS * RHS, where DST has the same width as the operands and
+ is filled with the least significant parts of the result. Returns
+ one if overflow occurred, otherwise zero. DST must be disjoint
+ from both operands. */
+int
+APInt::tcMultiply(integerPart *dst, const integerPart *lhs,
+ const integerPart *rhs, unsigned int parts)
+{
+ unsigned int i;
+ int overflow;
+
+ assert(dst != lhs && dst != rhs);
+
+ overflow = 0;
+ tcSet(dst, 0, parts);
+
+ for (i = 0; i < parts; i++)
+ overflow |= tcMultiplyPart(&dst[i], lhs, rhs[i], 0, parts,
+ parts - i, true);
+
+ return overflow;
+}
+
+/* DST = LHS * RHS, where DST has width the sum of the widths of the
+ operands. No overflow occurs. DST must be disjoint from both
+ operands. Returns the number of parts required to hold the
+ result. */
+unsigned int
+APInt::tcFullMultiply(integerPart *dst, const integerPart *lhs,
+ const integerPart *rhs, unsigned int lhsParts,
+ unsigned int rhsParts)
+{
+ /* Put the narrower number on the LHS for less loops below. */
+ if (lhsParts > rhsParts) {
+ return tcFullMultiply (dst, rhs, lhs, rhsParts, lhsParts);
+ } else {
+ unsigned int n;
+ assert(dst != lhs && dst != rhs);
+
+ tcSet(dst, 0, rhsParts);
+
+ for (n = 0; n < lhsParts; n++)
+ tcMultiplyPart(&dst[n], rhs, lhs[n], 0, rhsParts, rhsParts + 1, true);
+
+ n = lhsParts + rhsParts;
+
+ return n - (dst[n - 1] == 0);
+ }
+}
+
+/* If RHS is zero LHS and REMAINDER are left unchanged, return one.
+ Otherwise set LHS to LHS / RHS with the fractional part discarded,
+ set REMAINDER to the remainder, return zero. i.e.
+
+ OLD_LHS = RHS * LHS + REMAINDER
+
+ SCRATCH is a bignum of the same size as the operands and result for
+ use by the routine; its contents need not be initialized and are
+ destroyed. LHS, REMAINDER and SCRATCH must be distinct.
+*/
+int
+APInt::tcDivide(integerPart *lhs, const integerPart *rhs,
+ integerPart *remainder, integerPart *srhs,
+ unsigned int parts)
+{
+ unsigned int n, shiftCount;
+ integerPart mask;
+
+ assert(lhs != remainder && lhs != srhs && remainder != srhs);
+
+ shiftCount = tcMSB(rhs, parts) + 1;
+ if (shiftCount == 0)
+ return true;
+
+ shiftCount = parts * integerPartWidth - shiftCount;
+ n = shiftCount / integerPartWidth;
+ mask = (integerPart) 1 << (shiftCount % integerPartWidth);
+
+ tcAssign(srhs, rhs, parts);
+ tcShiftLeft(srhs, parts, shiftCount);
+ tcAssign(remainder, lhs, parts);
+ tcSet(lhs, 0, parts);
+
+ /* Loop, subtracting SRHS if REMAINDER is greater and adding that to
+ the total. */
+ for (;;) {
+ int compare;
+
+ compare = tcCompare(remainder, srhs, parts);
+ if (compare >= 0) {
+ tcSubtract(remainder, srhs, 0, parts);
+ lhs[n] |= mask;
+ }
+
+ if (shiftCount == 0)
+ break;
+ shiftCount--;
+ tcShiftRight(srhs, parts, 1);
+ if ((mask >>= 1) == 0)
+ mask = (integerPart) 1 << (integerPartWidth - 1), n--;
+ }
+
+ return false;
+}
+
+/* Shift a bignum left COUNT bits in-place. Shifted in bits are zero.
+ There are no restrictions on COUNT. */
+void
+APInt::tcShiftLeft(integerPart *dst, unsigned int parts, unsigned int count)
+{
+ if (count) {
+ unsigned int jump, shift;
+
+ /* Jump is the inter-part jump; shift is is intra-part shift. */
+ jump = count / integerPartWidth;
+ shift = count % integerPartWidth;
+
+ while (parts > jump) {
+ integerPart part;
+
+ parts--;
+
+ /* dst[i] comes from the two parts src[i - jump] and, if we have
+ an intra-part shift, src[i - jump - 1]. */
+ part = dst[parts - jump];
+ if (shift) {
+ part <<= shift;
+ if (parts >= jump + 1)
+ part |= dst[parts - jump - 1] >> (integerPartWidth - shift);
+ }
+
+ dst[parts] = part;
+ }
+
+ while (parts > 0)
+ dst[--parts] = 0;
+ }
+}
+
+/* Shift a bignum right COUNT bits in-place. Shifted in bits are
+ zero. There are no restrictions on COUNT. */
+void
+APInt::tcShiftRight(integerPart *dst, unsigned int parts, unsigned int count)
+{
+ if (count) {
+ unsigned int i, jump, shift;
+
+ /* Jump is the inter-part jump; shift is is intra-part shift. */
+ jump = count / integerPartWidth;
+ shift = count % integerPartWidth;
+
+ /* Perform the shift. This leaves the most significant COUNT bits
+ of the result at zero. */
+ for (i = 0; i < parts; i++) {
+ integerPart part;
+
+ if (i + jump >= parts) {
+ part = 0;
+ } else {
+ part = dst[i + jump];
+ if (shift) {
+ part >>= shift;
+ if (i + jump + 1 < parts)
+ part |= dst[i + jump + 1] << (integerPartWidth - shift);
+ }
+ }
+
+ dst[i] = part;
+ }
+ }
+}
+
+/* Bitwise and of two bignums. */
+void
+APInt::tcAnd(integerPart *dst, const integerPart *rhs, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ dst[i] &= rhs[i];
+}
+
+/* Bitwise inclusive or of two bignums. */
+void
+APInt::tcOr(integerPart *dst, const integerPart *rhs, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ dst[i] |= rhs[i];
+}
+
+/* Bitwise exclusive or of two bignums. */
+void
+APInt::tcXor(integerPart *dst, const integerPart *rhs, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ dst[i] ^= rhs[i];
+}
+
+/* Complement a bignum in-place. */
+void
+APInt::tcComplement(integerPart *dst, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ dst[i] = ~dst[i];
+}
+
+/* Comparison (unsigned) of two bignums. */
+int
+APInt::tcCompare(const integerPart *lhs, const integerPart *rhs,
+ unsigned int parts)
+{
+ while (parts) {
+ parts--;
+ if (lhs[parts] == rhs[parts])
+ continue;
+
+ if (lhs[parts] > rhs[parts])
+ return 1;
+ else
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Increment a bignum in-place, return the carry flag. */
+integerPart
+APInt::tcIncrement(integerPart *dst, unsigned int parts)
+{
+ unsigned int i;
+
+ for (i = 0; i < parts; i++)
+ if (++dst[i] != 0)
+ break;
+
+ return i == parts;
+}
+
+/* Set the least significant BITS bits of a bignum, clear the
+ rest. */
+void
+APInt::tcSetLeastSignificantBits(integerPart *dst, unsigned int parts,
+ unsigned int bits)
+{
+ unsigned int i;
+
+ i = 0;
+ while (bits > integerPartWidth) {
+ dst[i++] = ~(integerPart) 0;
+ bits -= integerPartWidth;
+ }
+
+ if (bits)
+ dst[i++] = ~(integerPart) 0 >> (integerPartWidth - bits);
+
+ while (i < parts)
+ dst[i++] = 0;
+}