llvm-project/llvm/lib/Support/APInt.cpp

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//===-- APInt.cpp - Implement APInt class ---------------------------------===//
//
// 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 implements a class to represent arbitrary precision integral
// constant values.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/APInt.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Support/MathExtras.h"
#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;
}
/// 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;
}
}
/// 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;
}
/// 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;
}
/// 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;
for (unsigned i = 0; i < len; ++i) {
uint64_t X = x[i];
x[i] -= cy;
if (cy > X)
cy = 1;
else {
cy = 0;
break;
}
}
return cy;
}
/// 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;
}
/// 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;
}
/// 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);
}
#if 0
/// 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;
}
#endif
APInt::APInt(unsigned numBits, uint64_t val)
: BitWidth(numBits) {
assert(BitWidth >= IntegerType::MIN_INT_BITS && "bitwidth too small");
assert(BitWidth <= IntegerType::MAX_INT_BITS && "bitwidth too large");
if (isSingleWord())
VAL = val & (~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitWidth));
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, unsigned numWords, uint64_t bigVal[])
: BitWidth(numBits) {
assert(BitWidth >= IntegerType::MIN_INT_BITS && "bitwidth too small");
assert(BitWidth <= IntegerType::MAX_INT_BITS && "bitwidth too large");
assert(bigVal && "Null pointer detected!");
if (isSingleWord())
VAL = bigVal[0] & (~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitWidth));
else {
// Memory allocation and check if successful.
assert((pVal = new uint64_t[getNumWords()]) &&
"APInt memory allocation fails!");
// Calculate the actual length of bigVal[].
unsigned maxN = std::max<unsigned>(numWords, getNumWords());
unsigned minN = std::min<unsigned>(numWords, getNumWords());
memcpy(pVal, bigVal, (minN - 1) * 8);
pVal[minN-1] = bigVal[minN-1] & (~uint64_t(0ULL) >> (64 - BitWidth % 64));
if (maxN == getNumWords())
memset(pVal+numWords, 0, (getNumWords() - numWords) * 8);
}
}
/// @brief Create a new APInt by translating the char array represented
/// integer value.
APInt::APInt(unsigned numbits, const char StrStart[], unsigned slen,
uint8_t radix) {
fromString(numbits, StrStart, slen, radix);
}
/// @brief Create a new APInt by translating the string represented
/// integer value.
APInt::APInt(unsigned numbits, const std::string& Val, uint8_t radix) {
assert(!Val.empty() && "String empty?");
fromString(numbits, Val.c_str(), Val.size(), radix);
}
/// @brief Converts a char array into an integer.
void APInt::fromString(unsigned numbits, 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 is null?");
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;
BitWidth = 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 20.
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)) {
BitWidth = 64;
VAL = strtoull(StrStart, 0, 10);
} else { // In case the value > 2^64 - 1
BitWidth = (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;
}
}
}
}
APInt::APInt(const APInt& APIVal)
: BitWidth(APIVal.BitWidth) {
if (isSingleWord()) VAL = APIVal.VAL;
else {
// Memory allocation and check if successful.
assert((pVal = new uint64_t[getNumWords()]) &&
"APInt memory allocation fails!");
memcpy(pVal, APIVal.pVal, getNumWords() * 8);
}
}
APInt::~APInt() {
if (!isSingleWord() && pVal) delete[] pVal;
}
/// @brief Copy assignment operator. Create a new object from the given
/// APInt one by initialization.
APInt& APInt::operator=(const APInt& RHS) {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
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);
}
return *this;
}
/// @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);
}
clearUnusedBits();
return *this;
}
/// @brief Prefix increment operator. Increments the APInt by one.
APInt& APInt::operator++() {
if (isSingleWord())
++VAL;
else
add_1(pVal, pVal, getNumWords(), 1);
clearUnusedBits();
return *this;
}
/// @brief Prefix decrement operator. Decrements the APInt by one.
APInt& APInt::operator--() {
if (isSingleWord()) --VAL;
else
sub_1(pVal, getNumWords(), 1);
clearUnusedBits();
return *this;
}
/// @brief Addition assignment operator. Adds this APInt by the given APInt&
/// RHS and assigns the result to this APInt.
APInt& APInt::operator+=(const APInt& RHS) {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord()) VAL += RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
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);
}
}
}
clearUnusedBits();
return *this;
}
/// @brief Subtraction assignment operator. Subtracts this APInt by the given
/// APInt &RHS and assigns the result to this APInt.
APInt& APInt::operator-=(const APInt& RHS) {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
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());
}
}
clearUnusedBits();
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) {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord()) VAL *= RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
else {
// one-based first non-zero bit position.
unsigned first = getActiveBits();
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.getActiveBits();
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;
}
}
clearUnusedBits();
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);
}
}
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];
}
}
clearUnusedBits();
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;
}
}
clearUnusedBits();
return *this;
}
/// @brief Bitwise AND operator. Performs bitwise AND operation on this APInt
/// and the given APInt& RHS.
APInt APInt::operator&(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(RHS);
return API &= *this;
}
/// @brief Bitwise OR operator. Performs bitwise OR operation on this APInt
/// and the given APInt& RHS.
APInt APInt::operator|(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(RHS);
API |= *this;
API.clearUnusedBits();
return API;
}
/// @brief Bitwise XOR operator. Performs bitwise XOR operation on this APInt
/// and the given APInt& RHS.
APInt APInt::operator^(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(RHS);
API ^= *this;
API.clearUnusedBits();
return API;
}
/// @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;
return true;
}
/// @brief Multiplication operator. Multiplies this APInt by the given APInt&
/// RHS.
APInt APInt::operator*(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(RHS);
API *= *this;
API.clearUnusedBits();
return API;
}
/// @brief Addition operator. Adds this APInt by the given APInt& RHS.
APInt APInt::operator+(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(*this);
API += RHS;
API.clearUnusedBits();
return API;
}
/// @brief Subtraction operator. Subtracts this APInt by the given APInt& RHS
APInt APInt::operator-(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(*this);
API -= RHS;
return API;
}
/// @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 = getActiveBits();
unsigned n2 = RHS.getActiveBits();
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;
}
/// @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 = getActiveBits();
if (n <= 64)
return pVal[0] == Val;
else
return false;
}
}
/// @brief Unsigned less than comparison
bool APInt::ult(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison");
if (isSingleWord())
return VAL < RHS.VAL;
else {
unsigned n1 = getActiveBits();
unsigned n2 = RHS.getActiveBits();
if (n1 < n2)
return true;
else if (n2 < n1)
return false;
else if (n1 <= 64 && n2 <= 64)
return pVal[0] < 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;
}
/// @brief Signed less than comparison
bool APInt::slt(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison");
if (isSingleWord())
return VAL < RHS.VAL;
else {
unsigned n1 = getActiveBits();
unsigned n2 = RHS.getActiveBits();
if (n1 < n2)
return true;
else if (n2 < n1)
return false;
else if (n1 <= 64 && n2 <= 64)
return pVal[0] < 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;
}
/// 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;
}
/// @brief Set every bit to 1.
APInt& APInt::set() {
if (isSingleWord()) VAL = ~0ULL >> (64 - BitWidth);
else {
for (unsigned i = 0; i < getNumWords() - 1; ++i)
pVal[i] = -1ULL;
pVal[getNumWords() - 1] = ~0ULL >> (64 - BitWidth % 64);
}
return *this;
}
/// 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 Set every bit to 0.
APInt& APInt::clear() {
if (isSingleWord()) VAL = 0;
else
memset(pVal, 0, getNumWords() * 8);
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;
}
/// @brief Toggle every bit to its opposite value.
APInt& APInt::flip() {
if (isSingleWord()) VAL = (~(VAL << (64 - BitWidth))) >> (64 - BitWidth);
else {
unsigned i = 0;
for (; i < getNumWords() - 1; ++i)
pVal[i] = ~pVal[i];
unsigned offset = 64 - (BitWidth - 64 * (i - 1));
pVal[i] = (~(pVal[i] << offset)) >> offset;
}
return *this;
}
/// 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 < 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::toString(uint8_t radix) const {
assert((radix == 10 || radix == 8 || radix == 16 || radix == 2) &&
"Radix should be 2, 8, 10, or 16!");
static const char *digits[] = {
"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"
};
std::string result;
unsigned bits_used = getActiveBits();
if (isSingleWord()) {
char buf[65];
const char *format = (radix == 10 ? "%llu" :
(radix == 16 ? "%llX" : (radix == 8 ? "%llo" : 0)));
if (format) {
sprintf(buf, format, VAL);
} else {
memset(buf, 0, 65);
uint64_t v = VAL;
while (bits_used) {
unsigned bit = v & 1;
bits_used--;
buf[bits_used] = digits[bit][0];
v >>=1;
}
}
result = buf;
return result;
}
APInt tmp(*this);
APInt divisor(tmp.getBitWidth(), radix);
APInt zero(tmp.getBitWidth(), 0);
if (tmp == 0)
result = "0";
else while (tmp.ne(zero)) {
APInt APdigit = APIntOps::urem(tmp,divisor);
unsigned digit = APdigit.getValue();
assert(digit < radix && "urem failed");
result.insert(0,digits[digit]);
tmp = APIntOps::udiv(tmp, divisor);
}
return result;
}
/// 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, 0);
APIVal.set();
if (isSign) APIVal.clear(numBits - 1);
return APIVal;
}
/// 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(numBits, 0);
if (isSign) APIVal.set(numBits - 1);
return APIVal;
}
/// 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);
}
/// getNullValue - This function creates an '0' value for an
/// APInt of the specified bit-width.
APInt APInt::getNullValue(unsigned numBits) {
return getMinValue(numBits, false);
}
/// HiBits - This function returns the high "numBits" bits of this APInt.
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::getLoBits(unsigned numBits) const {
return APIntOps::lshr(APIntOps::shl(*this, BitWidth - numBits),
BitWidth - numBits);
}
bool APInt::isPowerOf2() const {
return (!!*this) && !(*this & (*this - APInt(BitWidth,1)));
}
/// 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)
break;
}
return Count;
}
/// countTrailingZeros - 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 {
if (isSingleWord())
return CountTrailingZeros_64(~VAL & (VAL - 1));
APInt Tmp( ~(*this) & ((*this) - APInt(BitWidth,1)) );
return getNumWords() * APINT_BITS_PER_WORD - Tmp.countLeadingZeros();
}
/// 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 {
if (isSingleWord())
return CountPopulation_64(VAL);
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 {
assert(BitWidth >= 16 && BitWidth % 16 == 0 && "Cannot byteswap!");
if (BitWidth == 16)
return APInt(BitWidth, ByteSwap_16(VAL));
else if (BitWidth == 32)
return APInt(BitWidth, ByteSwap_32(VAL));
else if (BitWidth == 48) {
uint64_t Tmp1 = ((VAL >> 32) << 16) | (VAL & 0xFFFF);
Tmp1 = ByteSwap_32(Tmp1);
uint64_t Tmp2 = (VAL >> 16) & 0xFFFF;
Tmp2 = ByteSwap_16(Tmp2);
return
APInt(BitWidth,
(Tmp1 & 0xff) | ((Tmp1<<16) & 0xffff00000000ULL) | (Tmp2 << 16));
} 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 / 8 / 2; ++i) {
char Tmp = pByte[i];
pByte[i] = pByte[BitWidth / 8 - 1 - i];
pByte[BitWidth / 8 - 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,
const APInt& API2) {
APInt A = API1, B = API2;
while (!!B) {
APInt T = B;
B = APIntOps::urem(A, B);
A = T;
}
return A;
}
2007-02-06 13:38:37 +08:00
/// DoubleRoundToAPInt - This function convert a double value to
/// a APInt value.
APInt llvm::APIntOps::RoundDoubleToAPInt(double Double) {
union {
double D;
uint64_t I;
} T;
T.D = Double;
bool isNeg = T.I >> 63;
int64_t exp = ((T.I >> 52) & 0x7ff) - 1023;
if (exp < 0)
return APInt(64ull, 0u);
uint64_t mantissa = ((T.I << 12) >> 12) | (1ULL << 52);
if (exp < 52)
return isNeg ? -APInt(64u, mantissa >> (52 - exp)) :
APInt(64u, mantissa >> (52 - exp));
APInt Tmp(exp + 1, mantissa);
Tmp = Tmp.shl(exp - 52);
return isNeg ? -Tmp : Tmp;
}
/// RoundToDouble - This function convert 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::roundToDouble(bool isSigned) const {
bool isNeg = isSigned ? (*this)[BitWidth-1] : false;
APInt Tmp(isNeg ? -(*this) : (*this));
if (Tmp.isSingleWord())
return isSigned ? double(int64_t(Tmp.VAL)) : double(Tmp.VAL);
unsigned n = Tmp.getActiveBits();
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.
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));
// The leading bit of mantissa is implicit, so get rid of it.
mantissa &= ~(1ULL << 52);
uint64_t sign = isNeg ? (1ULL << 63) : 0;
exp += 1023;
union {
double D;
uint64_t I;
} T;
T.I = sign | (exp << 52) | mantissa;
return T.D;
}
// Truncate to new width.
void APInt::trunc(unsigned width) {
assert(width < BitWidth && "Invalid APInt Truncate request");
}
// Sign extend to a new width.
void APInt::sext(unsigned width) {
assert(width > BitWidth && "Invalid APInt SignExtend request");
}
// Zero extend to a new width.
void APInt::zext(unsigned width) {
assert(width > BitWidth && "Invalid APInt ZeroExtend request");
}
/// 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.BitWidth)) >> (64 - API.BitWidth))
>> shiftAmt) & (~uint64_t(0UL) >> (64 - API.BitWidth));
else {
if (shiftAmt >= API.BitWidth) {
memset(API.pVal, API[API.BitWidth-1] ? 1 : 0, (API.getNumWords()-1) * 8);
API.pVal[API.getNumWords() - 1] = ~uint64_t(0UL) >>
(64 - API.BitWidth % 64);
} else {
unsigned i = 0;
for (; i < API.BitWidth - shiftAmt; ++i)
if (API[i+shiftAmt])
API.set(i);
else
API.clear(i);
for (; i < API.BitWidth; ++i)
if (API[API.BitWidth-1])
API.set(i);
else API.clear(i);
}
}
return API;
}
/// 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.BitWidth)
memset(API.pVal, 0, API.getNumWords() * 8);
unsigned i = 0;
for (i = 0; i < API.BitWidth - shiftAmt; ++i)
if (API[i+shiftAmt]) API.set(i);
else API.clear(i);
for (; i < API.BitWidth; ++i)
API.clear(i);
}
return API;
}
/// 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.BitWidth)
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);
}
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;
}
API.clearUnusedBits();
return API;
}
/// Unsigned divide this APInt by APInt RHS.
/// @brief Unsigned division function for APInt.
APInt APInt::udiv(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(*this);
unsigned first = RHS.getActiveBits();
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.getActiveBits();
unsigned xlen = !first2 ? 0 : APInt::whichWord(first2 - 1) + 1;
if (!xlen)
return API;
else if (xlen < ylen || API.ult(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];
else {
APInt X(BitWidth, 0);
APInt Y(BitWidth, 0);
if (unsigned nshift = 63 - (first - 1) % 64) {
Y = APIntOps::shl(RHS, nshift);
X = APIntOps::shl(API, nshift);
++xlen;
}
div((unsigned*)X.pVal, xlen*2-1,
(unsigned*)(Y.isSingleWord() ? &Y.VAL : Y.pVal), ylen*2);
memset(API.pVal, 0, API.getNumWords() * 8);
memcpy(API.pVal, X.pVal + ylen, (xlen - ylen) * 8);
}
}
return API;
}
/// Unsigned remainder operation on APInt.
/// @brief Function for unsigned remainder operation.
APInt APInt::urem(const APInt& RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
APInt API(*this);
unsigned first = RHS.getActiveBits();
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]);
} else {
unsigned first2 = API.getActiveBits();
unsigned xlen = !first2 ? 0 : API.whichWord(first2 - 1) + 1;
if (!xlen || xlen < ylen || API.ult(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 {
APInt X((xlen+1)*64, 0), Y(ylen*64, 0);
unsigned nshift = 63 - (first - 1) % 64;
if (nshift) {
APIntOps::shl(Y, nshift);
APIntOps::shl(X, nshift);
}
div((unsigned*)X.pVal, xlen*2-1,
(unsigned*)(Y.isSingleWord() ? &Y.VAL : Y.pVal), ylen*2);
memset(API.pVal, 0, API.getNumWords() * 8);
for (unsigned i = 0; i < ylen-1; ++i)
API.pVal[i] = (X.pVal[i] >> nshift) | (X.pVal[i+1] << (64 - nshift));
API.pVal[ylen-1] = X.pVal[ylen-1] >> nshift;
}
}
return API;
}