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Diffstat (limited to 'kernel/arch/arm/nwfpe/softfloat-macros')
| -rw-r--r-- | kernel/arch/arm/nwfpe/softfloat-macros | 754 |
1 files changed, 754 insertions, 0 deletions
diff --git a/kernel/arch/arm/nwfpe/softfloat-macros b/kernel/arch/arm/nwfpe/softfloat-macros new file mode 100644 index 000000000..cf2a61731 --- /dev/null +++ b/kernel/arch/arm/nwfpe/softfloat-macros @@ -0,0 +1,754 @@ + +/* +=============================================================================== + +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 ); + +} + |