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-rw-r--r--lib/Support/APInt.cpp334
1 files changed, 145 insertions, 189 deletions
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index d84bb6472a..6d98b554c8 100644
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -8,8 +8,8 @@
//
//===----------------------------------------------------------------------===//
//
-// 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.
//
//===----------------------------------------------------------------------===//
@@ -26,8 +26,8 @@
using namespace llvm;
-// A utility function for allocating memory, checking for allocation failures,
-// and ensuring the contents are zeroed.
+/// A utility function for allocating memory, checking for allocation failures,
+/// and ensuring the contents are zeroed.
inline static uint64_t* getClearedMemory(uint32_t numWords) {
uint64_t * result = new uint64_t[numWords];
assert(result && "APInt memory allocation fails!");
@@ -35,8 +35,8 @@ inline static uint64_t* getClearedMemory(uint32_t numWords) {
return result;
}
-// A utility function for allocating memory and checking for allocation failure.
-// The content is not zero'd
+/// A utility function for allocating memory and checking for allocation
+/// failure. The content is not zeroed.
inline static uint64_t* getMemory(uint32_t numWords) {
uint64_t * result = new uint64_t[numWords];
assert(result && "APInt memory allocation fails!");
@@ -47,12 +47,13 @@ APInt::APInt(uint32_t numBits, uint64_t val)
: BitWidth(numBits), VAL(0) {
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));
+ if (isSingleWord())
+ VAL = val;
else {
pVal = getClearedMemory(getNumWords());
pVal[0] = val;
}
+ clearUnusedBits();
}
APInt::APInt(uint32_t numBits, uint32_t numWords, uint64_t bigVal[])
@@ -124,7 +125,7 @@ APInt& APInt::operator=(uint64_t RHS) {
/// "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 uint64_t add_1(uint64_t dest[], uint64_t x[], uint32_t len, uint64_t y) {
+static bool add_1(uint64_t dest[], uint64_t x[], uint32_t len, uint64_t y) {
for (uint32_t i = 0; i < len; ++i) {
dest[i] = y + x[i];
if (dest[i] < y)
@@ -143,8 +144,7 @@ APInt& APInt::operator++() {
++VAL;
else
add_1(pVal, pVal, getNumWords(), 1);
- clearUnusedBits();
- return *this;
+ return clearUnusedBits();
}
/// sub_1 - This function subtracts a single "digit" (64-bit word), y, from
@@ -152,8 +152,8 @@ APInt& APInt::operator++() {
/// 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.
-static uint64_t sub_1(uint64_t x[], uint32_t len,
- uint64_t y) {
+/// @returns the borrow out of the subtraction
+static bool sub_1(uint64_t x[], uint32_t len, uint64_t y) {
for (uint32_t i = 0; i < len; ++i) {
uint64_t X = x[i];
x[i] -= y;
@@ -164,7 +164,7 @@ static uint64_t sub_1(uint64_t x[], uint32_t len,
break; // Remaining digits are unchanged so exit early
}
}
- return y;
+ return bool(y);
}
/// @brief Prefix decrement operator. Decrements the APInt by one.
@@ -173,12 +173,13 @@ APInt& APInt::operator--() {
--VAL;
else
sub_1(pVal, getNumWords(), 1);
- clearUnusedBits();
- return *this;
+ return clearUnusedBits();
}
-/// add - This function adds the integer array x[] by integer array
-/// y[] and returns the carry.
+/// 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,
uint32_t len) {
bool carry = false;
@@ -190,8 +191,9 @@ static bool add(uint64_t *dest, const uint64_t *x, const uint64_t *y,
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) {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
@@ -199,12 +201,12 @@ APInt& APInt::operator+=(const APInt& RHS) {
else {
add(pVal, pVal, RHS.pVal, getNumWords());
}
- clearUnusedBits();
- return *this;
+ return clearUnusedBits();
}
-/// sub - This function subtracts the integer array x[] by
-/// integer array y[], and returns the borrow-out.
+/// 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,
uint32_t len) {
bool borrow = false;
@@ -216,29 +218,33 @@ static bool sub(uint64_t *dest, const uint64_t *x, const uint64_t *y,
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) {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
VAL -= RHS.VAL;
else
sub(pVal, pVal, RHS.pVal, getNumWords());
- clearUnusedBits();
- return *this;
+ return clearUnusedBits();
}
-/// 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.
+/// Multiplies an integer array, x by a 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[], uint32_t 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, lx, hx;
+ uint64_t carry = 0;
+
+ // For each digit of x.
for (uint32_t i = 0; i < len; ++i) {
- lx = x[i] & 0xffffffffULL;
- hx = x[i] >> 32;
- // hasCarry - A flag to indicate if has carry.
+ // 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.
@@ -256,13 +262,12 @@ static uint64_t mul_1(uint64_t dest[], uint64_t x[], uint32_t len, uint64_t y) {
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.
+/// 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[], uint32_t xlen, uint64_t y[],
uint32_t ylen) {
dest[xlen] = mul_1(dest, x, xlen, y[0]);
@@ -293,8 +298,6 @@ static void mul(uint64_t dest[], uint64_t x[], uint32_t xlen, uint64_t y[],
}
}
-/// @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()) {
@@ -336,8 +339,6 @@ APInt& APInt::operator*=(const APInt& RHS) {
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()) {
@@ -350,8 +351,6 @@ APInt& APInt::operator&=(const APInt& RHS) {
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()) {
@@ -364,8 +363,6 @@ APInt& APInt::operator|=(const APInt& RHS) {
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()) {
@@ -376,56 +373,47 @@ APInt& APInt::operator^=(const APInt& RHS) {
uint32_t numWords = getNumWords();
for (uint32_t i = 0; i < numWords; ++i)
pVal[i] ^= RHS.pVal[i];
- this->clearUnusedBits();
- return *this;
+ 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 {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
return APInt(getBitWidth(), VAL & RHS.VAL);
- APInt Result(*this);
uint32_t numWords = getNumWords();
+ uint64_t* val = getMemory(numWords);
for (uint32_t i = 0; i < numWords; ++i)
- Result.pVal[i] &= RHS.pVal[i];
- return Result;
+ 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 {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
return APInt(getBitWidth(), VAL | RHS.VAL);
- APInt Result(*this);
uint32_t numWords = getNumWords();
+ uint64_t *val = getMemory(numWords);
for (uint32_t i = 0; i < numWords; ++i)
- Result.pVal[i] |= RHS.pVal[i];
- return Result;
+ 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 {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
- if (isSingleWord()) {
- APInt Result(BitWidth, VAL ^ RHS.VAL);
- Result.clearUnusedBits();
- return Result;
- }
- APInt Result(*this);
+ if (isSingleWord())
+ return APInt(BitWidth, VAL ^ RHS.VAL).clearUnusedBits();
+
uint32_t numWords = getNumWords();
+ uint64_t *val = getMemory(numWords);
for (uint32_t i = 0; i < numWords; ++i)
- Result.pVal[i] ^= RHS.pVal[i];
- return Result;
+ val[i] = pVal[i] ^ RHS.pVal[i];
+
+ // 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;
@@ -436,77 +424,61 @@ bool APInt::operator !() const {
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");
- if (isSingleWord()) {
- APInt Result(BitWidth, VAL * RHS.VAL);
- Result.clearUnusedBits();
- return Result;
- }
+ if (isSingleWord())
+ return APInt(BitWidth, VAL * RHS.VAL).clearUnusedBits();
APInt Result(*this);
Result *= RHS;
- Result.clearUnusedBits();
- return Result;
+ return Result.clearUnusedBits();
}
-/// @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");
- if (isSingleWord()) {
- APInt Result(BitWidth, VAL + RHS.VAL);
- Result.clearUnusedBits();
- return Result;
- }
+ if (isSingleWord())
+ return APInt(BitWidth, VAL + RHS.VAL).clearUnusedBits();
APInt Result(BitWidth, 0);
add(Result.pVal, this->pVal, RHS.pVal, getNumWords());
- Result.clearUnusedBits();
- return Result;
+ return Result.clearUnusedBits();
}
-/// @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");
- if (isSingleWord()) {
- APInt Result(BitWidth, VAL - RHS.VAL);
- Result.clearUnusedBits();
- return Result;
- }
+ if (isSingleWord())
+ return APInt(BitWidth, VAL - RHS.VAL).clearUnusedBits();
APInt Result(BitWidth, 0);
sub(Result.pVal, this->pVal, RHS.pVal, getNumWords());
- Result.clearUnusedBits();
- return Result;
+ return Result.clearUnusedBits();
}
-/// @brief Array-indexing support.
bool APInt::operator[](uint32_t bitPosition) const {
- return (maskBit(bitPosition) & (isSingleWord() ?
- VAL : pVal[whichWord(bitPosition)])) != 0;
+ 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 {
if (isSingleWord())
return VAL == RHS.VAL;
+ // Get some facts about the number of bits used in the two operands.
uint32_t n1 = getActiveBits();
uint32_t 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 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;
@@ -518,29 +490,37 @@ bool APInt::operator==(uint64_t Val) const {
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 {
- uint32_t n1 = getActiveBits();
- uint32_t n2 = RHS.getActiveBits();
- if (n1 < n2)
- return true;
- else if (n2 < n1)
+
+ // Get active bit length of both operands
+ uint32_t n1 = getActiveBits();
+ uint32_t n2 = RHS.getActiveBits();
+
+ // If magnitude of LHS is less than RHS, return true.
+ if (n1 < n2)
+ return true;
+
+ // If magnitude of RHS is greather than LHS, return false.
+ if (n2 < n1)
+ return false;
+
+ // 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
+ for (int i = whichWord(n1 - 1); i >= 0; --i) {
+ if (pVal[i] > RHS.pVal[i])
return false;
- else if (n1 <= APINT_BITS_PER_WORD && n2 <= APINT_BITS_PER_WORD)
- 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;
- }
+ 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()) {
@@ -554,15 +534,20 @@ bool APInt::slt(const APInt& RHS) const {
bool lhsNegative = false;
bool rhsNegative = false;
if (lhs[BitWidth-1]) {
+ // Sign bit is set so make a note of it and perform two's complement
lhsNegative = true;
lhs.flip();
lhs++;
}
if (rhs[BitWidth-1]) {
+ // Sign bit is set so make a note of it and perform two's complement
rhsNegative = true;
rhs.flip();
rhs++;
}
+
+ // Now we have unsigned values to compare so do the comparison if necessary
+ // based on the negativeness of the values.
if (lhsNegative)
if (rhsNegative)
return !lhs.ult(rhs);
@@ -574,25 +559,25 @@ bool APInt::slt(const APInt& RHS) const {
return lhs.ult(rhs);
}
-/// Set the given bit to 1 whose poition is given as "bitPosition".
-/// @brief Set a given bit to 1.
APInt& APInt::set(uint32_t bitPosition) {
- if (isSingleWord()) VAL |= maskBit(bitPosition);
- else pVal[whichWord(bitPosition)] |= maskBit(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 >> (APINT_BITS_PER_WORD - BitWidth);
- else {
- for (uint32_t i = 0; i < getNumWords() - 1; ++i)
- pVal[i] = -1ULL;
- pVal[getNumWords() - 1] = ~0ULL >>
- (APINT_BITS_PER_WORD - BitWidth % APINT_BITS_PER_WORD);
+ if (isSingleWord()) {
+ VAL = -1ULL;
+ return clearUnusedBits();
}
- return *this;
+
+ // Set all the bits in all the words.
+ for (uint32_t i = 0; i < getNumWords() - 1; ++i)
+ pVal[i] = -1ULL;
+ // Clear the unused ones
+ return clearUnusedBits();
}
/// Set the given bit to 0 whose position is given as "bitPosition".
@@ -695,11 +680,6 @@ 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.
uint32_t APInt::countLeadingZeros() const {
uint32_t Count = 0;
if (isSingleWord())
@@ -720,11 +700,6 @@ uint32_t APInt::countLeadingZeros() const {
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.
uint32_t APInt::countTrailingZeros() const {
if (isSingleWord())
return CountTrailingZeros_64(VAL);
@@ -732,10 +707,6 @@ uint32_t APInt::countTrailingZeros() const {
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.
uint32_t APInt::countPopulation() const {
if (isSingleWord())
return CountPopulation_64(VAL);
@@ -745,9 +716,6 @@ uint32_t APInt::countPopulation() const {
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)
@@ -776,8 +744,6 @@ APInt APInt::byteSwap() const {
}
}
-/// 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;
@@ -789,8 +755,6 @@ APInt llvm::APIntOps::GreatestCommonDivisor(const APInt& API1,
return A;
}
-/// DoubleRoundToAPInt - This function convert a double value to
-/// a APInt value.
APInt llvm::APIntOps::RoundDoubleToAPInt(double Double) {
union {
double D;
@@ -879,16 +843,19 @@ double APInt::roundToDouble(bool isSigned) const {
// Truncate to new width.
void APInt::trunc(uint32_t width) {
assert(width < BitWidth && "Invalid APInt Truncate request");
+ // FIXME: implement
}
// Sign extend to a new width.
void APInt::sext(uint32_t width) {
assert(width > BitWidth && "Invalid APInt SignExtend request");
+ // FIXME: implement
}
// Zero extend to a new width.
void APInt::zext(uint32_t width) {
assert(width > BitWidth && "Invalid APInt ZeroExtend request");
+ // FIXME: implement
}
/// Arithmetic right-shift this APInt by shiftAmt.
@@ -896,33 +863,32 @@ void APInt::zext(uint32_t width) {
APInt APInt::ashr(uint32_t shiftAmt) const {
if (isSingleWord()) {
if (shiftAmt == BitWidth)
- return APInt(BitWidth, -1ull);
+ return APInt(BitWidth, -1ULL);
else
return APInt(BitWidth,
(((int64_t(VAL) << (APINT_BITS_PER_WORD - BitWidth)) >>
- (APINT_BITS_PER_WORD - BitWidth)) >> shiftAmt) &
- (~uint64_t(0UL) >> (APINT_BITS_PER_WORD - BitWidth)));
+ (APINT_BITS_PER_WORD - BitWidth)) >> shiftAmt)).clearUnusedBits();
}
APInt Result(*this);
if (shiftAmt >= BitWidth) {
memset(Result.pVal, Result[BitWidth-1] ? 1 : 0,
(getNumWords()-1) * APINT_WORD_SIZE);
- Result.pVal[getNumWords() - 1] = ~uint64_t(0UL) >>
- (APINT_BITS_PER_WORD - BitWidth % APINT_BITS_PER_WORD);
- } else {
- uint32_t i = 0;
- for (; i < BitWidth - shiftAmt; ++i)
- if (Result[i+shiftAmt])
- Result.set(i);
- else
- Result.clear(i);
- for (; i < BitWidth; ++i)
- if (Result[BitWidth-1])
- Result.set(i);
- else
- Result.clear(i);
- }
+ return Result.clearUnusedBits();
+ }
+
+ // FIXME: bit-at-a-time shift is really slow.
+ uint32_t i = 0;
+ for (; i < BitWidth - shiftAmt; ++i)
+ if (Result[i+shiftAmt])
+ Result.set(i);
+ else
+ Result.clear(i);
+ for (; i < BitWidth; ++i)
+ if (Result[BitWidth-1])
+ Result.set(i);
+ else
+ Result.clear(i);
return Result;
}
@@ -936,8 +902,12 @@ APInt APInt::lshr(uint32_t shiftAmt) const {
return APInt(BitWidth, this->VAL >> shiftAmt);
APInt Result(*this);
- if (shiftAmt >= Result.BitWidth)
- memset(Result.pVal, 0, Result.getNumWords() * APINT_WORD_SIZE);
+ if (shiftAmt >= BitWidth) {
+ Result.clear();
+ return Result;
+ }
+
+ // FIXME: bit at a time shift is really slow
uint32_t i = 0;
for (i = 0; i < Result.BitWidth - shiftAmt; ++i)
if (Result[i+shiftAmt])
@@ -956,9 +926,7 @@ APInt APInt::shl(uint32_t shiftAmt) const {
if (isSingleWord()) {
if (shiftAmt == BitWidth)
return APInt(BitWidth, 0); // avoid undefined shift results
- return APInt(BitWidth, (VAL << shiftAmt) &
- (~uint64_t(0ULL) >>
- (APINT_BITS_PER_WORD - BitWidth)));
+ return APInt(BitWidth, VAL << shiftAmt).clearUnusedBits();
}
// If all the bits were shifted out, the result is 0. This avoids issues
@@ -978,8 +946,7 @@ APInt APInt::shl(uint32_t shiftAmt) const {
val[i] = pVal[i] << shiftAmt | carry;
carry = pVal[i] >> (APINT_BITS_PER_WORD - shiftAmt);
}
- val[getNumWords()-1] &= ~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitWidth);
- return APInt(val, BitWidth);
+ return APInt(val, BitWidth).clearUnusedBits();
}
// Compute some values needed by the remaining shift algorithms
@@ -992,8 +959,7 @@ APInt APInt::shl(uint32_t shiftAmt) const {
val[i] = 0;
for (uint32_t i = offset; i < getNumWords(); i++)
val[i] = pVal[i-offset];
- val[getNumWords()-1] &= ~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitWidth);
- return APInt(val,BitWidth);
+ return APInt(val,BitWidth).clearUnusedBits();
}
// Copy whole words from this to Result.
@@ -1004,8 +970,7 @@ APInt APInt::shl(uint32_t shiftAmt) const {
val[offset] = pVal[0] << wordShift;
for (i = 0; i < offset; ++i)
val[i] = 0;
- val[getNumWords()-1] &= ~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - BitWidth);
- return APInt(val, BitWidth);
+ return APInt(val, BitWidth).clearUnusedBits();
}
/// Implementation of Knuth's Algorithm D (Division of nonnegative integers)
@@ -1185,9 +1150,6 @@ static void KnuthDiv(uint32_t *u, uint32_t *v, uint32_t *q, uint32_t* r,
DEBUG(cerr << std::setbase(10) << '\n');
}
-// This function makes calling KnuthDiv a little more convenient. It uses
-// APInt parameters instead of uint32_t* parameters. It can also divide APInt
-// values of different widths.
void APInt::divide(const APInt LHS, uint32_t lhsWords,
const APInt &RHS, uint32_t rhsWords,
APInt *Quotient, APInt *Remainder)
@@ -1364,8 +1326,6 @@ void APInt::divide(const APInt LHS, uint32_t lhsWords,
}
}
-/// 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");
@@ -1403,8 +1363,6 @@ APInt APInt::udiv(const APInt& RHS) const {
return Quotient;
}
-/// 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");
if (isSingleWord()) {
@@ -1442,7 +1400,6 @@ APInt APInt::urem(const APInt& RHS) const {
return Remainder;
}
-/// @brief Converts a char array into an integer.
void APInt::fromString(uint32_t numbits, const char *str, uint32_t slen,
uint8_t radix) {
// Check our assumptions here
@@ -1498,7 +1455,6 @@ void APInt::fromString(uint32_t numbits, const char *str, uint32_t slen,
}
}
-/// to_string - This function translates the APInt into a string.
std::string APInt::toString(uint8_t radix, bool wantSigned) const {
assert((radix == 10 || radix == 8 || radix == 16 || radix == 2) &&
"Radix should be 2, 8, 10, or 16!");
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-05-01 07:29:40 +0000