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- /*
- ===============================================================================
- This C source fragment is part of the SoftFloat IEC/IEEE Floating-point
- Arithmetic Package, Release 2.
- Written by John R. Hauser. This work was made possible in part by the
- International Computer Science Institute, located at Suite 600, 1947 Center
- Street, Berkeley, California 94704. Funding was partially provided by the
- National Science Foundation under grant MIP-9311980. The original version
- of this code was written as part of a project to build a fixed-point vector
- processor in collaboration with the University of California at Berkeley,
- overseen by Profs. Nelson Morgan and John Wawrzynek. More information
- is available through the web page
- http://www.jhauser.us/arithmetic/SoftFloat-2b/SoftFloat-source.txt
- THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort
- has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
- TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO
- PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
- AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
- Derivative works are acceptable, even for commercial purposes, so long as
- (1) they include prominent notice that the work is derivative, and (2) they
- include prominent notice akin to these three paragraphs for those parts of
- this code that are retained.
- ===============================================================================
- */
- /*
- -------------------------------------------------------------------------------
- Shifts `a' right by the number of bits given in `count'. If any nonzero
- bits are shifted off, they are ``jammed'' into the least significant bit of
- the result by setting the least significant bit to 1. The value of `count'
- can be arbitrarily large; in particular, if `count' is greater than 32, the
- result will be either 0 or 1, depending on whether `a' is zero or nonzero.
- The result is stored in the location pointed to by `zPtr'.
- -------------------------------------------------------------------------------
- */
- INLINE void shift32RightJamming( bits32 a, int16 count, bits32 *zPtr )
- {
- bits32 z;
- if ( count == 0 ) {
- z = a;
- }
- else if ( count < 32 ) {
- z = ( a>>count ) | ( ( a<<( ( - count ) & 31 ) ) != 0 );
- }
- else {
- z = ( a != 0 );
- }
- *zPtr = z;
- }
- /*
- -------------------------------------------------------------------------------
- Shifts `a' right by the number of bits given in `count'. If any nonzero
- bits are shifted off, they are ``jammed'' into the least significant bit of
- the result by setting the least significant bit to 1. The value of `count'
- can be arbitrarily large; in particular, if `count' is greater than 64, the
- result will be either 0 or 1, depending on whether `a' is zero or nonzero.
- The result is stored in the location pointed to by `zPtr'.
- -------------------------------------------------------------------------------
- */
- INLINE void shift64RightJamming( bits64 a, int16 count, bits64 *zPtr )
- {
- bits64 z;
- __asm__("@shift64RightJamming -- start");
- if ( count == 0 ) {
- z = a;
- }
- else if ( count < 64 ) {
- z = ( a>>count ) | ( ( a<<( ( - count ) & 63 ) ) != 0 );
- }
- else {
- z = ( a != 0 );
- }
- __asm__("@shift64RightJamming -- end");
- *zPtr = z;
- }
- /*
- -------------------------------------------------------------------------------
- Shifts the 128-bit value formed by concatenating `a0' and `a1' right by 64
- _plus_ the number of bits given in `count'. The shifted result is at most
- 64 nonzero bits; this is stored at the location pointed to by `z0Ptr'. The
- bits shifted off form a second 64-bit result as follows: The _last_ bit
- shifted off is the most-significant bit of the extra result, and the other
- 63 bits of the extra result are all zero if and only if _all_but_the_last_
- bits shifted off were all zero. This extra result is stored in the location
- pointed to by `z1Ptr'. The value of `count' can be arbitrarily large.
- (This routine makes more sense if `a0' and `a1' are considered to form a
- fixed-point value with binary point between `a0' and `a1'. This fixed-point
- value is shifted right by the number of bits given in `count', and the
- integer part of the result is returned at the location pointed to by
- `z0Ptr'. The fractional part of the result may be slightly corrupted as
- described above, and is returned at the location pointed to by `z1Ptr'.)
- -------------------------------------------------------------------------------
- */
- INLINE void
- shift64ExtraRightJamming(
- bits64 a0, bits64 a1, int16 count, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- bits64 z0, z1;
- int8 negCount = ( - count ) & 63;
- if ( count == 0 ) {
- z1 = a1;
- z0 = a0;
- }
- else if ( count < 64 ) {
- z1 = ( a0<<negCount ) | ( a1 != 0 );
- z0 = a0>>count;
- }
- else {
- if ( count == 64 ) {
- z1 = a0 | ( a1 != 0 );
- }
- else {
- z1 = ( ( a0 | a1 ) != 0 );
- }
- z0 = 0;
- }
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Shifts the 128-bit value formed by concatenating `a0' and `a1' right by the
- number of bits given in `count'. Any bits shifted off are lost. The value
- of `count' can be arbitrarily large; in particular, if `count' is greater
- than 128, the result will be 0. The result is broken into two 64-bit pieces
- which are stored at the locations pointed to by `z0Ptr' and `z1Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- shift128Right(
- bits64 a0, bits64 a1, int16 count, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- bits64 z0, z1;
- int8 negCount = ( - count ) & 63;
- if ( count == 0 ) {
- z1 = a1;
- z0 = a0;
- }
- else if ( count < 64 ) {
- z1 = ( a0<<negCount ) | ( a1>>count );
- z0 = a0>>count;
- }
- else {
- z1 = ( count < 64 ) ? ( a0>>( count & 63 ) ) : 0;
- z0 = 0;
- }
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Shifts the 128-bit value formed by concatenating `a0' and `a1' right by the
- number of bits given in `count'. If any nonzero bits are shifted off, they
- are ``jammed'' into the least significant bit of the result by setting the
- least significant bit to 1. The value of `count' can be arbitrarily large;
- in particular, if `count' is greater than 128, the result will be either 0
- or 1, depending on whether the concatenation of `a0' and `a1' is zero or
- nonzero. The result is broken into two 64-bit pieces which are stored at
- the locations pointed to by `z0Ptr' and `z1Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- shift128RightJamming(
- bits64 a0, bits64 a1, int16 count, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- bits64 z0, z1;
- int8 negCount = ( - count ) & 63;
- if ( count == 0 ) {
- z1 = a1;
- z0 = a0;
- }
- else if ( count < 64 ) {
- z1 = ( a0<<negCount ) | ( a1>>count ) | ( ( a1<<negCount ) != 0 );
- z0 = a0>>count;
- }
- else {
- if ( count == 64 ) {
- z1 = a0 | ( a1 != 0 );
- }
- else if ( count < 128 ) {
- z1 = ( a0>>( count & 63 ) ) | ( ( ( a0<<negCount ) | a1 ) != 0 );
- }
- else {
- z1 = ( ( a0 | a1 ) != 0 );
- }
- z0 = 0;
- }
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Shifts the 192-bit value formed by concatenating `a0', `a1', and `a2' right
- by 64 _plus_ the number of bits given in `count'. The shifted result is
- at most 128 nonzero bits; these are broken into two 64-bit pieces which are
- stored at the locations pointed to by `z0Ptr' and `z1Ptr'. The bits shifted
- off form a third 64-bit result as follows: The _last_ bit shifted off is
- the most-significant bit of the extra result, and the other 63 bits of the
- extra result are all zero if and only if _all_but_the_last_ bits shifted off
- were all zero. This extra result is stored in the location pointed to by
- `z2Ptr'. The value of `count' can be arbitrarily large.
- (This routine makes more sense if `a0', `a1', and `a2' are considered
- to form a fixed-point value with binary point between `a1' and `a2'. This
- fixed-point value is shifted right by the number of bits given in `count',
- and the integer part of the result is returned at the locations pointed to
- by `z0Ptr' and `z1Ptr'. The fractional part of the result may be slightly
- corrupted as described above, and is returned at the location pointed to by
- `z2Ptr'.)
- -------------------------------------------------------------------------------
- */
- INLINE void
- shift128ExtraRightJamming(
- bits64 a0,
- bits64 a1,
- bits64 a2,
- int16 count,
- bits64 *z0Ptr,
- bits64 *z1Ptr,
- bits64 *z2Ptr
- )
- {
- bits64 z0, z1, z2;
- int8 negCount = ( - count ) & 63;
- if ( count == 0 ) {
- z2 = a2;
- z1 = a1;
- z0 = a0;
- }
- else {
- if ( count < 64 ) {
- z2 = a1<<negCount;
- z1 = ( a0<<negCount ) | ( a1>>count );
- z0 = a0>>count;
- }
- else {
- if ( count == 64 ) {
- z2 = a1;
- z1 = a0;
- }
- else {
- a2 |= a1;
- if ( count < 128 ) {
- z2 = a0<<negCount;
- z1 = a0>>( count & 63 );
- }
- else {
- z2 = ( count == 128 ) ? a0 : ( a0 != 0 );
- z1 = 0;
- }
- }
- z0 = 0;
- }
- z2 |= ( a2 != 0 );
- }
- *z2Ptr = z2;
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Shifts the 128-bit value formed by concatenating `a0' and `a1' left by the
- number of bits given in `count'. Any bits shifted off are lost. The value
- of `count' must be less than 64. The result is broken into two 64-bit
- pieces which are stored at the locations pointed to by `z0Ptr' and `z1Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- shortShift128Left(
- bits64 a0, bits64 a1, int16 count, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- *z1Ptr = a1<<count;
- *z0Ptr =
- ( count == 0 ) ? a0 : ( a0<<count ) | ( a1>>( ( - count ) & 63 ) );
- }
- /*
- -------------------------------------------------------------------------------
- Shifts the 192-bit value formed by concatenating `a0', `a1', and `a2' left
- by the number of bits given in `count'. Any bits shifted off are lost.
- The value of `count' must be less than 64. The result is broken into three
- 64-bit pieces which are stored at the locations pointed to by `z0Ptr',
- `z1Ptr', and `z2Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- shortShift192Left(
- bits64 a0,
- bits64 a1,
- bits64 a2,
- int16 count,
- bits64 *z0Ptr,
- bits64 *z1Ptr,
- bits64 *z2Ptr
- )
- {
- bits64 z0, z1, z2;
- int8 negCount;
- z2 = a2<<count;
- z1 = a1<<count;
- z0 = a0<<count;
- if ( 0 < count ) {
- negCount = ( ( - count ) & 63 );
- z1 |= a2>>negCount;
- z0 |= a1>>negCount;
- }
- *z2Ptr = z2;
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Adds the 128-bit value formed by concatenating `a0' and `a1' to the 128-bit
- value formed by concatenating `b0' and `b1'. Addition is modulo 2^128, so
- any carry out is lost. The result is broken into two 64-bit pieces which
- are stored at the locations pointed to by `z0Ptr' and `z1Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- add128(
- bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- bits64 z1;
- z1 = a1 + b1;
- *z1Ptr = z1;
- *z0Ptr = a0 + b0 + ( z1 < a1 );
- }
- /*
- -------------------------------------------------------------------------------
- Adds the 192-bit value formed by concatenating `a0', `a1', and `a2' to the
- 192-bit value formed by concatenating `b0', `b1', and `b2'. Addition is
- modulo 2^192, so any carry out is lost. The result is broken into three
- 64-bit pieces which are stored at the locations pointed to by `z0Ptr',
- `z1Ptr', and `z2Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- add192(
- bits64 a0,
- bits64 a1,
- bits64 a2,
- bits64 b0,
- bits64 b1,
- bits64 b2,
- bits64 *z0Ptr,
- bits64 *z1Ptr,
- bits64 *z2Ptr
- )
- {
- bits64 z0, z1, z2;
- int8 carry0, carry1;
- z2 = a2 + b2;
- carry1 = ( z2 < a2 );
- z1 = a1 + b1;
- carry0 = ( z1 < a1 );
- z0 = a0 + b0;
- z1 += carry1;
- z0 += ( z1 < carry1 );
- z0 += carry0;
- *z2Ptr = z2;
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Subtracts the 128-bit value formed by concatenating `b0' and `b1' from the
- 128-bit value formed by concatenating `a0' and `a1'. Subtraction is modulo
- 2^128, so any borrow out (carry out) is lost. The result is broken into two
- 64-bit pieces which are stored at the locations pointed to by `z0Ptr' and
- `z1Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- sub128(
- bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- *z1Ptr = a1 - b1;
- *z0Ptr = a0 - b0 - ( a1 < b1 );
- }
- /*
- -------------------------------------------------------------------------------
- Subtracts the 192-bit value formed by concatenating `b0', `b1', and `b2'
- from the 192-bit value formed by concatenating `a0', `a1', and `a2'.
- Subtraction is modulo 2^192, so any borrow out (carry out) is lost. The
- result is broken into three 64-bit pieces which are stored at the locations
- pointed to by `z0Ptr', `z1Ptr', and `z2Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- sub192(
- bits64 a0,
- bits64 a1,
- bits64 a2,
- bits64 b0,
- bits64 b1,
- bits64 b2,
- bits64 *z0Ptr,
- bits64 *z1Ptr,
- bits64 *z2Ptr
- )
- {
- bits64 z0, z1, z2;
- int8 borrow0, borrow1;
- z2 = a2 - b2;
- borrow1 = ( a2 < b2 );
- z1 = a1 - b1;
- borrow0 = ( a1 < b1 );
- z0 = a0 - b0;
- z0 -= ( z1 < borrow1 );
- z1 -= borrow1;
- z0 -= borrow0;
- *z2Ptr = z2;
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Multiplies `a' by `b' to obtain a 128-bit product. The product is broken
- into two 64-bit pieces which are stored at the locations pointed to by
- `z0Ptr' and `z1Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void mul64To128( bits64 a, bits64 b, bits64 *z0Ptr, bits64 *z1Ptr )
- {
- bits32 aHigh, aLow, bHigh, bLow;
- bits64 z0, zMiddleA, zMiddleB, z1;
- aLow = a;
- aHigh = a>>32;
- bLow = b;
- bHigh = b>>32;
- z1 = ( (bits64) aLow ) * bLow;
- zMiddleA = ( (bits64) aLow ) * bHigh;
- zMiddleB = ( (bits64) aHigh ) * bLow;
- z0 = ( (bits64) aHigh ) * bHigh;
- zMiddleA += zMiddleB;
- z0 += ( ( (bits64) ( zMiddleA < zMiddleB ) )<<32 ) + ( zMiddleA>>32 );
- zMiddleA <<= 32;
- z1 += zMiddleA;
- z0 += ( z1 < zMiddleA );
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Multiplies the 128-bit value formed by concatenating `a0' and `a1' by `b' to
- obtain a 192-bit product. The product is broken into three 64-bit pieces
- which are stored at the locations pointed to by `z0Ptr', `z1Ptr', and
- `z2Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- mul128By64To192(
- bits64 a0,
- bits64 a1,
- bits64 b,
- bits64 *z0Ptr,
- bits64 *z1Ptr,
- bits64 *z2Ptr
- )
- {
- bits64 z0, z1, z2, more1;
- mul64To128( a1, b, &z1, &z2 );
- mul64To128( a0, b, &z0, &more1 );
- add128( z0, more1, 0, z1, &z0, &z1 );
- *z2Ptr = z2;
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Multiplies the 128-bit value formed by concatenating `a0' and `a1' to the
- 128-bit value formed by concatenating `b0' and `b1' to obtain a 256-bit
- product. The product is broken into four 64-bit pieces which are stored at
- the locations pointed to by `z0Ptr', `z1Ptr', `z2Ptr', and `z3Ptr'.
- -------------------------------------------------------------------------------
- */
- INLINE void
- mul128To256(
- bits64 a0,
- bits64 a1,
- bits64 b0,
- bits64 b1,
- bits64 *z0Ptr,
- bits64 *z1Ptr,
- bits64 *z2Ptr,
- bits64 *z3Ptr
- )
- {
- bits64 z0, z1, z2, z3;
- bits64 more1, more2;
- mul64To128( a1, b1, &z2, &z3 );
- mul64To128( a1, b0, &z1, &more2 );
- add128( z1, more2, 0, z2, &z1, &z2 );
- mul64To128( a0, b0, &z0, &more1 );
- add128( z0, more1, 0, z1, &z0, &z1 );
- mul64To128( a0, b1, &more1, &more2 );
- add128( more1, more2, 0, z2, &more1, &z2 );
- add128( z0, z1, 0, more1, &z0, &z1 );
- *z3Ptr = z3;
- *z2Ptr = z2;
- *z1Ptr = z1;
- *z0Ptr = z0;
- }
- /*
- -------------------------------------------------------------------------------
- Returns an approximation to the 64-bit integer quotient obtained by dividing
- `b' into the 128-bit value formed by concatenating `a0' and `a1'. The
- divisor `b' must be at least 2^63. If q is the exact quotient truncated
- toward zero, the approximation returned lies between q and q + 2 inclusive.
- If the exact quotient q is larger than 64 bits, the maximum positive 64-bit
- unsigned integer is returned.
- -------------------------------------------------------------------------------
- */
- static bits64 estimateDiv128To64( bits64 a0, bits64 a1, bits64 b )
- {
- bits64 b0, b1;
- bits64 rem0, rem1, term0, term1;
- bits64 z;
- if ( b <= a0 ) return LIT64( 0xFFFFFFFFFFFFFFFF );
- b0 = b>>32; /* hence b0 is 32 bits wide now */
- if ( b0<<32 <= a0 ) {
- z = LIT64( 0xFFFFFFFF00000000 );
- } else {
- z = a0;
- do_div( z, b0 );
- z <<= 32;
- }
- mul64To128( b, z, &term0, &term1 );
- sub128( a0, a1, term0, term1, &rem0, &rem1 );
- while ( ( (sbits64) rem0 ) < 0 ) {
- z -= LIT64( 0x100000000 );
- b1 = b<<32;
- add128( rem0, rem1, b0, b1, &rem0, &rem1 );
- }
- rem0 = ( rem0<<32 ) | ( rem1>>32 );
- if ( b0<<32 <= rem0 ) {
- z |= 0xFFFFFFFF;
- } else {
- do_div( rem0, b0 );
- z |= rem0;
- }
- return z;
- }
- /*
- -------------------------------------------------------------------------------
- Returns an approximation to the square root of the 32-bit significand given
- by `a'. Considered as an integer, `a' must be at least 2^31. If bit 0 of
- `aExp' (the least significant bit) is 1, the integer returned approximates
- 2^31*sqrt(`a'/2^31), where `a' is considered an integer. If bit 0 of `aExp'
- is 0, the integer returned approximates 2^31*sqrt(`a'/2^30). In either
- case, the approximation returned lies strictly within +/-2 of the exact
- value.
- -------------------------------------------------------------------------------
- */
- static bits32 estimateSqrt32( int16 aExp, bits32 a )
- {
- static const bits16 sqrtOddAdjustments[] = {
- 0x0004, 0x0022, 0x005D, 0x00B1, 0x011D, 0x019F, 0x0236, 0x02E0,
- 0x039C, 0x0468, 0x0545, 0x0631, 0x072B, 0x0832, 0x0946, 0x0A67
- };
- static const bits16 sqrtEvenAdjustments[] = {
- 0x0A2D, 0x08AF, 0x075A, 0x0629, 0x051A, 0x0429, 0x0356, 0x029E,
- 0x0200, 0x0179, 0x0109, 0x00AF, 0x0068, 0x0034, 0x0012, 0x0002
- };
- int8 index;
- bits32 z;
- bits64 A;
- index = ( a>>27 ) & 15;
- if ( aExp & 1 ) {
- z = 0x4000 + ( a>>17 ) - sqrtOddAdjustments[ index ];
- z = ( ( a / z )<<14 ) + ( z<<15 );
- a >>= 1;
- }
- else {
- z = 0x8000 + ( a>>17 ) - sqrtEvenAdjustments[ index ];
- z = a / z + z;
- z = ( 0x20000 <= z ) ? 0xFFFF8000 : ( z<<15 );
- if ( z <= a ) return (bits32) ( ( (sbits32) a )>>1 );
- }
- A = ( (bits64) a )<<31;
- do_div( A, z );
- return ( (bits32) A ) + ( z>>1 );
- }
- /*
- -------------------------------------------------------------------------------
- Returns the number of leading 0 bits before the most-significant 1 bit
- of `a'. If `a' is zero, 32 is returned.
- -------------------------------------------------------------------------------
- */
- static int8 countLeadingZeros32( bits32 a )
- {
- static const int8 countLeadingZerosHigh[] = {
- 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
- 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
- };
- int8 shiftCount;
- shiftCount = 0;
- if ( a < 0x10000 ) {
- shiftCount += 16;
- a <<= 16;
- }
- if ( a < 0x1000000 ) {
- shiftCount += 8;
- a <<= 8;
- }
- shiftCount += countLeadingZerosHigh[ a>>24 ];
- return shiftCount;
- }
- /*
- -------------------------------------------------------------------------------
- Returns the number of leading 0 bits before the most-significant 1 bit
- of `a'. If `a' is zero, 64 is returned.
- -------------------------------------------------------------------------------
- */
- static int8 countLeadingZeros64( bits64 a )
- {
- int8 shiftCount;
- shiftCount = 0;
- if ( a < ( (bits64) 1 )<<32 ) {
- shiftCount += 32;
- }
- else {
- a >>= 32;
- }
- shiftCount += countLeadingZeros32( a );
- return shiftCount;
- }
- /*
- -------------------------------------------------------------------------------
- Returns 1 if the 128-bit value formed by concatenating `a0' and `a1'
- is equal to the 128-bit value formed by concatenating `b0' and `b1'.
- Otherwise, returns 0.
- -------------------------------------------------------------------------------
- */
- INLINE flag eq128( bits64 a0, bits64 a1, bits64 b0, bits64 b1 )
- {
- return ( a0 == b0 ) && ( a1 == b1 );
- }
- /*
- -------------------------------------------------------------------------------
- Returns 1 if the 128-bit value formed by concatenating `a0' and `a1' is less
- than or equal to the 128-bit value formed by concatenating `b0' and `b1'.
- Otherwise, returns 0.
- -------------------------------------------------------------------------------
- */
- INLINE flag le128( bits64 a0, bits64 a1, bits64 b0, bits64 b1 )
- {
- return ( a0 < b0 ) || ( ( a0 == b0 ) && ( a1 <= b1 ) );
- }
- /*
- -------------------------------------------------------------------------------
- Returns 1 if the 128-bit value formed by concatenating `a0' and `a1' is less
- than the 128-bit value formed by concatenating `b0' and `b1'. Otherwise,
- returns 0.
- -------------------------------------------------------------------------------
- */
- INLINE flag lt128( bits64 a0, bits64 a1, bits64 b0, bits64 b1 )
- {
- return ( a0 < b0 ) || ( ( a0 == b0 ) && ( a1 < b1 ) );
- }
- /*
- -------------------------------------------------------------------------------
- Returns 1 if the 128-bit value formed by concatenating `a0' and `a1' is
- not equal to the 128-bit value formed by concatenating `b0' and `b1'.
- Otherwise, returns 0.
- -------------------------------------------------------------------------------
- */
- INLINE flag ne128( bits64 a0, bits64 a1, bits64 b0, bits64 b1 )
- {
- return ( a0 != b0 ) || ( a1 != b1 );
- }
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