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-rw-r--r--externals/g3dlite/G3D.lib/source/uint128.cpp155
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diff --git a/externals/g3dlite/G3D.lib/source/uint128.cpp b/externals/g3dlite/G3D.lib/source/uint128.cpp
deleted file mode 100644
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--- a/externals/g3dlite/G3D.lib/source/uint128.cpp
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@@ -1,155 +0,0 @@
-/**
- @file uint128.cpp
-
- @maintainer Morgan McGuire, matrix@graphics3d.com
- @author Kyle Whitson
-
- @created 2008-07-17
- @edited 2008-07-17
- */
-
-#include "G3D/uint128.h"
-
-namespace G3D {
-
-/** Adds two 64-bit integers, placing the result and the overflow into 64-bit integers.*/
-static void addAndCarry(const uint64& _a, const uint64& _b, uint64& carry, uint64& result) {
-
- // Break each number into 4 32-bit chunks. Since we are using uints, right-shifting will fill with zeros.
- // This eliminates the need to and with 0xFFFFFFFF.
- uint32 a [2] = {_a & 0xFFFFFFFF, _a >> 32};
- uint32 b [2] = {_b & 0xFFFFFFFF, _b >> 32};
-
- uint64 tmp = uint64(a[0]) + b[0];
-
- result = tmp & 0xFFFFFFFF;
- uint32 c = tmp >> 32;
-
- tmp = uint64(c) + a[1] + b[1];
- result += tmp << 32;
- carry = (tmp >> 32);
-}
-
-/** Multiplies two unsigned 64-bit integers, placing the result into one 64-bit int and the overflow into another.*/
-void multiplyAndCarry(const uint64& _a, const uint64& _b, uint64& carry, uint64& result) {
-
- // Break each number into 4 32-bit chunks. Since we are using uints, right-shifting will fill with zeros.
- // This eliminates the need to and with 0xFFFFFFFF.
- uint32 a [2] = {_a & 0xFFFFFFFF, _a >> 32};
- uint32 b [2] = {_b & 0xFFFFFFFF, _b >> 32};
-
- uint64 prod [2][2];
- for(int i = 0; i < 2; ++i) {
- for(int j = 0; j < 2; ++j) {
- prod[i][j] = uint64(a[i]) * b[j];
- }
- }
-
- // The product of the low bits of a and b will always fit into the result
- result = prod[0][0];
-
- // The product of the high bits of a and b will never fit into the result
- carry = prod[1][1];
-
- // The high 32 bits of prod[0][1] and prod[1][0] will never fit into the result
- carry += prod[0][1] >> 32;
- carry += prod[1][0] >> 32;
-
- uint64 tmp;
- addAndCarry(result, (prod[0][1] << 32), tmp, result);
- carry += tmp;
- addAndCarry(result, (prod[1][0] << 32), tmp, result);
- carry += tmp;
-}
-
-
-uint128::uint128(const uint64& hi, const uint64& lo) : hi(hi), lo(lo) {
-}
-
-uint128::uint128(const uint64& lo) : hi(0), lo(lo) {
-}
-
-uint128& uint128::operator+=(const uint128& x) {
-
- G3D::uint64 carry;
- addAndCarry(lo, x.lo, carry, lo);
-
- // Adding the carry will change hi. Save the old hi bits in case this == x.
- const uint64 xHi = x.hi;
- hi += carry;
- hi += xHi;
- return *this;
-}
-
-uint128& uint128::operator*=(const uint128& x) {
-
- // The low bits will get overwritten when doing the multiply, so back up both (in case &x == this)
- const uint64 oldLo = lo;
- const uint64 oldXLo = x.lo;
-
- G3D::uint64 carry;
- multiplyAndCarry(oldLo, oldXLo, carry, lo);
-
- // Overflow doesn't matter here because the result is going into hi - any overflow will exceed the capacity of a 128-bit number
- // Note: hi * x.hi will always overflow, since (x * 2^64) * (y * 2^64) = x*y*(2^128). The largest number expressable in 128 bits is
- // 2^128 - 1.
- hi = carry + (oldLo * x.hi) + (hi * oldXLo);
-
- return *this;
-}
-
-uint128& uint128::operator^=(const uint128& x) {
- hi ^= x.hi;
- lo ^= x.lo;
- return *this;
-}
-
-uint128& uint128::operator&=(const uint128& x) {
- hi &= x.hi;
- lo &= x.lo;
- return *this;
-}
-
-uint128& uint128::operator|=(const uint128& x) {
- hi |= x.hi;
- lo |= x.lo;
- return *this;
-}
-
-bool uint128::operator==(const uint128& x) {
- return (hi == x.hi) && (lo == x.lo);
-}
-
-uint128& uint128::operator>>=(const int x) {
-
- //Before shifting, mask out the bits that will be shifted out of hi.
- //Put a 1 in the first bit that will not be lost in the shift, then subtract 1 to get the mask.
- uint64 mask = ((uint64)1L << x) - 1;
- uint64 tmp = hi & mask;
- hi >>= x;
-
- //Shift lo and add the bits shifted down from hi
- lo = (lo >> x) + (tmp << (64 - x));
-
- return *this;
-}
-
-uint128& uint128::operator<<=(const int x) {
-
- //Before shifting, mask out the bits that will be shifted out of lo.
- //Put a 1 in the last bit that will be lost in the shift, then subtract 1 to get the logical inverse of the mask.
- //A bitwise NOT will then produce the correct mask.
- uint64 mask = ~((((uint64)1L) << (64 - x)) - 1);
- uint64 tmp = lo & mask;
- lo <<= x;
-
- //Shift hi and add the bits shifted up from lo
- hi = (hi << x) + (tmp >> (64 - x));
-
- return *this;
-}
-
-uint128 uint128::operator&(const uint128& x) {
- return uint128(hi & x.hi, lo & x.lo);
-}
-}