soft float support

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1332 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 720 insertions, 0 deletions

diff --git a/fpu/softfloat-macros.h b/fpu/softfloat-macros.h
new file mode 100644
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+
+/*============================================================================
+
+This C source fragment is part of the SoftFloat IEC/IEEE Floating-point
+Arithmetic Package, Release 2b.
+
+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.cs.berkeley.edu/~jhauser/
+arithmetic/SoftFloat.html'.
+
+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 ALL LOSSES,
+COSTS, OR OTHER PROBLEMS THEY INCUR DUE TO THE SOFTWARE, AND WHO FURTHERMORE
+EFFECTIVELY INDEMNIFY JOHN HAUSER AND THE INTERNATIONAL COMPUTER SCIENCE
+INSTITUTE (possibly via similar legal notice) AGAINST ALL LOSSES, COSTS, OR
+OTHER PROBLEMS INCURRED BY THEIR CUSTOMERS AND CLIENTS DUE TO THE SOFTWARE.
+
+Derivative works are acceptable, even for commercial purposes, so long as
+(1) the source code for the derivative work includes prominent notice that
+the work is derivative, and (2) the source code includes prominent notice with
+these four 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;
+
+    if ( count == 0 ) {
+        z = a;
+    }
+    else if ( count < 64 ) {
+        z = ( a>>count ) | ( ( a<<( ( - count ) & 63 ) ) != 0 );
+    }
+    else {
+        z = ( a != 0 );
+    }
+    *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;
+    z = ( b0<<32 <= a0 ) ? LIT64( 0xFFFFFFFF00000000 ) : ( a0 / b0 )<<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 );
+    z |= ( b0<<32 <= rem0 ) ? 0xFFFFFFFF : rem0 / b0;
+    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;
+
+    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 );
+    }
+    return ( (bits32) ( ( ( (bits64) a )<<31 ) / z ) ) + ( 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 );
+
+}
+