softfloat: export some functions

Move fpu/softfloat-macros.h to include/fpu/

Export floatx80 functions to be used by target floatx80
specific implementations.

Exports:
  propagateFloatx80NaN(), extractFloatx80Frac(),
  extractFloatx80Exp(), extractFloatx80Sign(),
  normalizeFloatx80Subnormal(), packFloatx80(),
  roundAndPackFloatx80(), normalizeRoundAndPackFloatx80()

Also exports packFloat32() that will be used to implement
m68k fsinh, fcos, fsin, ftan operations.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180224201802.911-2-laurent@vivier.eu>

1 files changed, 841 insertions, 0 deletions

diff --git a/include/fpu/softfloat-macros.h b/include/fpu/softfloat-macros.h
new file mode 100644
index 0000000000..35e1603a5e
--- /dev/null
+++ b/include/fpu/softfloat-macros.h
@@ -0,0 +1,841 @@
+/*
+ * QEMU float support macros
+ *
+ * The code in this source file is derived from release 2a of the SoftFloat
+ * IEC/IEEE Floating-point Arithmetic Package. Those parts of the code (and
+ * some later contributions) are provided under that license, as detailed below.
+ * It has subsequently been modified by contributors to the QEMU Project,
+ * so some portions are provided under:
+ *  the SoftFloat-2a license
+ *  the BSD license
+ *  GPL-v2-or-later
+ *
+ * Any future contributions to this file after December 1st 2014 will be
+ * taken to be licensed under the Softfloat-2a license unless specifically
+ * indicated otherwise.
+ */
+
+/*
+===============================================================================
+This C source fragment is part of the SoftFloat IEC/IEEE Floating-point
+Arithmetic Package, Release 2a.
+
+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://HTTP.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 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 four paragraphs for those parts of
+this code that are retained.
+
+===============================================================================
+*/
+
+/* BSD licensing:
+ * Copyright (c) 2006, Fabrice Bellard
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors
+ * may be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/* Portions of this work are licensed under the terms of the GNU GPL,
+ * version 2 or later. See the COPYING file in the top-level directory.
+ */
+
+/*----------------------------------------------------------------------------
+| This macro tests for minimum version of the GNU C compiler.
+*----------------------------------------------------------------------------*/
+#if defined(__GNUC__) && defined(__GNUC_MINOR__)
+# define SOFTFLOAT_GNUC_PREREQ(maj, min) \
+         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
+#else
+# define SOFTFLOAT_GNUC_PREREQ(maj, min) 0
+#endif
+
+
+/*----------------------------------------------------------------------------
+| 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void shift32RightJamming(uint32_t a, int count, uint32_t *zPtr)
+{
+    uint32_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void shift64RightJamming(uint64_t a, int count, uint64_t *zPtr)
+{
+    uint64_t 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'.)
+*----------------------------------------------------------------------------*/
+
+static inline void
+ shift64ExtraRightJamming(
+     uint64_t a0, uint64_t a1, int count, uint64_t *z0Ptr, uint64_t *z1Ptr)
+{
+    uint64_t z0, z1;
+    int8_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ shift128Right(
+     uint64_t a0, uint64_t a1, int count, uint64_t *z0Ptr, uint64_t *z1Ptr)
+{
+    uint64_t z0, z1;
+    int8_t 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 < 128) ? (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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ shift128RightJamming(
+     uint64_t a0, uint64_t a1, int count, uint64_t *z0Ptr, uint64_t *z1Ptr)
+{
+    uint64_t z0, z1;
+    int8_t 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'.)
+*----------------------------------------------------------------------------*/
+
+static inline void
+ shift128ExtraRightJamming(
+     uint64_t a0,
+     uint64_t a1,
+     uint64_t a2,
+     int count,
+     uint64_t *z0Ptr,
+     uint64_t *z1Ptr,
+     uint64_t *z2Ptr
+ )
+{
+    uint64_t z0, z1, z2;
+    int8_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ shortShift128Left(
+     uint64_t a0, uint64_t a1, int count, uint64_t *z0Ptr, uint64_t *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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ shortShift192Left(
+     uint64_t a0,
+     uint64_t a1,
+     uint64_t a2,
+     int count,
+     uint64_t *z0Ptr,
+     uint64_t *z1Ptr,
+     uint64_t *z2Ptr
+ )
+{
+    uint64_t z0, z1, z2;
+    int8_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ add128(
+     uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1, uint64_t *z0Ptr, uint64_t *z1Ptr )
+{
+    uint64_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ add192(
+     uint64_t a0,
+     uint64_t a1,
+     uint64_t a2,
+     uint64_t b0,
+     uint64_t b1,
+     uint64_t b2,
+     uint64_t *z0Ptr,
+     uint64_t *z1Ptr,
+     uint64_t *z2Ptr
+ )
+{
+    uint64_t z0, z1, z2;
+    int8_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ sub128(
+     uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1, uint64_t *z0Ptr, uint64_t *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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ sub192(
+     uint64_t a0,
+     uint64_t a1,
+     uint64_t a2,
+     uint64_t b0,
+     uint64_t b1,
+     uint64_t b2,
+     uint64_t *z0Ptr,
+     uint64_t *z1Ptr,
+     uint64_t *z2Ptr
+ )
+{
+    uint64_t z0, z1, z2;
+    int8_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void mul64To128( uint64_t a, uint64_t b, uint64_t *z0Ptr, uint64_t *z1Ptr )
+{
+    uint32_t aHigh, aLow, bHigh, bLow;
+    uint64_t z0, zMiddleA, zMiddleB, z1;
+
+    aLow = a;
+    aHigh = a>>32;
+    bLow = b;
+    bHigh = b>>32;
+    z1 = ( (uint64_t) aLow ) * bLow;
+    zMiddleA = ( (uint64_t) aLow ) * bHigh;
+    zMiddleB = ( (uint64_t) aHigh ) * bLow;
+    z0 = ( (uint64_t) aHigh ) * bHigh;
+    zMiddleA += zMiddleB;
+    z0 += ( ( (uint64_t) ( 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ mul128By64To192(
+     uint64_t a0,
+     uint64_t a1,
+     uint64_t b,
+     uint64_t *z0Ptr,
+     uint64_t *z1Ptr,
+     uint64_t *z2Ptr
+ )
+{
+    uint64_t 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'.
+*----------------------------------------------------------------------------*/
+
+static inline void
+ mul128To256(
+     uint64_t a0,
+     uint64_t a1,
+     uint64_t b0,
+     uint64_t b1,
+     uint64_t *z0Ptr,
+     uint64_t *z1Ptr,
+     uint64_t *z2Ptr,
+     uint64_t *z3Ptr
+ )
+{
+    uint64_t z0, z1, z2, z3;
+    uint64_t 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 inline uint64_t estimateDiv128To64(uint64_t a0, uint64_t a1, uint64_t b)
+{
+    uint64_t b0, b1;
+    uint64_t rem0, rem1, term0, term1;
+    uint64_t 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 ( ( (int64_t) 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;
+
+}
+
+/* From the GNU Multi Precision Library - longlong.h __udiv_qrnnd
+ * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
+ *
+ * Licensed under the GPLv2/LGPLv3
+ */
+static inline uint64_t div128To64(uint64_t n0, uint64_t n1, uint64_t d)
+{
+    uint64_t d0, d1, q0, q1, r1, r0, m;
+
+    d0 = (uint32_t)d;
+    d1 = d >> 32;
+
+    r1 = n1 % d1;
+    q1 = n1 / d1;
+    m = q1 * d0;
+    r1 = (r1 << 32) | (n0 >> 32);
+    if (r1 < m) {
+        q1 -= 1;
+        r1 += d;
+        if (r1 >= d) {
+            if (r1 < m) {
+                q1 -= 1;
+                r1 += d;
+            }
+        }
+    }
+    r1 -= m;
+
+    r0 = r1 % d1;
+    q0 = r1 / d1;
+    m = q0 * d0;
+    r0 = (r0 << 32) | (uint32_t)n0;
+    if (r0 < m) {
+        q0 -= 1;
+        r0 += d;
+        if (r0 >= d) {
+            if (r0 < m) {
+                q0 -= 1;
+                r0 += d;
+            }
+        }
+    }
+    r0 -= m;
+
+    /* Return remainder in LSB */
+    return (q1 << 32) | q0 | (r0 != 0);
+}
+
+/*----------------------------------------------------------------------------
+| 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 inline uint32_t estimateSqrt32(int aExp, uint32_t a)
+{
+    static const uint16_t sqrtOddAdjustments[] = {
+        0x0004, 0x0022, 0x005D, 0x00B1, 0x011D, 0x019F, 0x0236, 0x02E0,
+        0x039C, 0x0468, 0x0545, 0x0631, 0x072B, 0x0832, 0x0946, 0x0A67
+    };
+    static const uint16_t sqrtEvenAdjustments[] = {
+        0x0A2D, 0x08AF, 0x075A, 0x0629, 0x051A, 0x0429, 0x0356, 0x029E,
+        0x0200, 0x0179, 0x0109, 0x00AF, 0x0068, 0x0034, 0x0012, 0x0002
+    };
+    int8_t index;
+    uint32_t z;
+
+    index = ( a>>27 ) & 15;
+    if ( aExp & 1 ) {
+        z = 0x4000 + ( a>>17 ) - sqrtOddAdjustments[ (int)index ];
+        z = ( ( a / z )<<14 ) + ( z<<15 );
+        a >>= 1;
+    }
+    else {
+        z = 0x8000 + ( a>>17 ) - sqrtEvenAdjustments[ (int)index ];
+        z = a / z + z;
+        z = ( 0x20000 <= z ) ? 0xFFFF8000 : ( z<<15 );
+        if ( z <= a ) return (uint32_t) ( ( (int32_t) a )>>1 );
+    }
+    return ( (uint32_t) ( ( ( (uint64_t) 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 inline int8_t countLeadingZeros32(uint32_t a)
+{
+#if SOFTFLOAT_GNUC_PREREQ(3, 4)
+    if (a) {
+        return __builtin_clz(a);
+    } else {
+        return 32;
+    }
+#else
+    static const int8_t 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_t shiftCount;
+
+    shiftCount = 0;
+    if ( a < 0x10000 ) {
+        shiftCount += 16;
+        a <<= 16;
+    }
+    if ( a < 0x1000000 ) {
+        shiftCount += 8;
+        a <<= 8;
+    }
+    shiftCount += countLeadingZerosHigh[ a>>24 ];
+    return shiftCount;
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| Returns the number of leading 0 bits before the most-significant 1 bit of
+| `a'.  If `a' is zero, 64 is returned.
+*----------------------------------------------------------------------------*/
+
+static inline int8_t countLeadingZeros64(uint64_t a)
+{
+#if SOFTFLOAT_GNUC_PREREQ(3, 4)
+    if (a) {
+        return __builtin_clzll(a);
+    } else {
+        return 64;
+    }
+#else
+    int8_t shiftCount;
+
+    shiftCount = 0;
+    if ( a < ( (uint64_t) 1 )<<32 ) {
+        shiftCount += 32;
+    }
+    else {
+        a >>= 32;
+    }
+    shiftCount += countLeadingZeros32( a );
+    return shiftCount;
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| 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.
+*----------------------------------------------------------------------------*/
+
+static inline flag eq128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t 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.
+*----------------------------------------------------------------------------*/
+
+static inline flag le128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t 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.
+*----------------------------------------------------------------------------*/
+
+static inline flag lt128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t 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.
+*----------------------------------------------------------------------------*/
+
+static inline flag ne128( uint64_t a0, uint64_t a1, uint64_t b0, uint64_t b1 )
+{
+
+    return ( a0 != b0 ) || ( a1 != b1 );
+
+}