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diff --git a/softfloat/f128_sqrt.c b/softfloat/f128_sqrt.c
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+
+/*============================================================================
+
+This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
+Package, Release 3e, by John R. Hauser.
+
+Copyright 2011, 2012, 2013, 2014, 2015, 2016, 2017 The Regents of the
+University of California. 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 University 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 REGENTS 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 REGENTS 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.
+
+=============================================================================*/
+
+#include <stdbool.h>
+#include <stdint.h>
+#include "platform.h"
+#include "internals.h"
+#include "specialize.h"
+#include "softfloat.h"
+
+float128_t f128_sqrt( float128_t a )
+{
+ union ui128_f128 uA;
+ uint_fast64_t uiA64, uiA0;
+ bool signA;
+ int_fast32_t expA;
+ struct uint128 sigA, uiZ;
+ struct exp32_sig128 normExpSig;
+ int_fast32_t expZ;
+ uint_fast32_t sig32A, recipSqrt32, sig32Z;
+ struct uint128 rem;
+ uint32_t qs[3];
+ uint_fast32_t q;
+ uint_fast64_t x64, sig64Z;
+ struct uint128 y, term;
+ uint_fast64_t sigZExtra;
+ struct uint128 sigZ;
+ union ui128_f128 uZ;
+
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ uA.f = a;
+ uiA64 = uA.ui.v64;
+ uiA0 = uA.ui.v0;
+ signA = signF128UI64( uiA64 );
+ expA = expF128UI64( uiA64 );
+ sigA.v64 = fracF128UI64( uiA64 );
+ sigA.v0 = uiA0;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( expA == 0x7FFF ) {
+ if ( sigA.v64 | sigA.v0 ) {
+ uiZ = softfloat_propagateNaNF128UI( uiA64, uiA0, 0, 0 );
+ goto uiZ;
+ }
+ if ( ! signA ) return a;
+ goto invalid;
+ }
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( signA ) {
+ if ( ! (expA | sigA.v64 | sigA.v0) ) return a;
+ goto invalid;
+ }
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( ! expA ) {
+ if ( ! (sigA.v64 | sigA.v0) ) return a;
+ normExpSig = softfloat_normSubnormalF128Sig( sigA.v64, sigA.v0 );
+ expA = normExpSig.exp;
+ sigA = normExpSig.sig;
+ }
+ /*------------------------------------------------------------------------
+ | (`sig32Z' is guaranteed to be a lower bound on the square root of
+ | `sig32A', which makes `sig32Z' also a lower bound on the square root of
+ | `sigA'.)
+ *------------------------------------------------------------------------*/
+ expZ = ((expA - 0x3FFF)>>1) + 0x3FFE;
+ expA &= 1;
+ sigA.v64 |= UINT64_C( 0x0001000000000000 );
+ sig32A = sigA.v64>>17;
+ recipSqrt32 = softfloat_approxRecipSqrt32_1( expA, sig32A );
+ sig32Z = ((uint_fast64_t) sig32A * recipSqrt32)>>32;
+ if ( expA ) {
+ sig32Z >>= 1;
+ rem = softfloat_shortShiftLeft128( sigA.v64, sigA.v0, 12 );
+ } else {
+ rem = softfloat_shortShiftLeft128( sigA.v64, sigA.v0, 13 );
+ }
+ qs[2] = sig32Z;
+ rem.v64 -= (uint_fast64_t) sig32Z * sig32Z;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ q = ((uint32_t) (rem.v64>>2) * (uint_fast64_t) recipSqrt32)>>32;
+ x64 = (uint_fast64_t) sig32Z<<32;
+ sig64Z = x64 + ((uint_fast64_t) q<<3);
+ y = softfloat_shortShiftLeft128( rem.v64, rem.v0, 29 );
+ /*------------------------------------------------------------------------
+ | (Repeating this loop is a rare occurrence.)
+ *------------------------------------------------------------------------*/
+ for (;;) {
+ term = softfloat_mul64ByShifted32To128( x64 + sig64Z, q );
+ rem = softfloat_sub128( y.v64, y.v0, term.v64, term.v0 );
+ if ( ! (rem.v64 & UINT64_C( 0x8000000000000000 )) ) break;
+ --q;
+ sig64Z -= 1<<3;
+ }
+ qs[1] = q;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ q = ((rem.v64>>2) * recipSqrt32)>>32;
+ y = softfloat_shortShiftLeft128( rem.v64, rem.v0, 29 );
+ sig64Z <<= 1;
+ /*------------------------------------------------------------------------
+ | (Repeating this loop is a rare occurrence.)
+ *------------------------------------------------------------------------*/
+ for (;;) {
+ term = softfloat_shortShiftLeft128( 0, sig64Z, 32 );
+ term = softfloat_add128( term.v64, term.v0, 0, (uint_fast64_t) q<<6 );
+ term = softfloat_mul128By32( term.v64, term.v0, q );
+ rem = softfloat_sub128( y.v64, y.v0, term.v64, term.v0 );
+ if ( ! (rem.v64 & UINT64_C( 0x8000000000000000 )) ) break;
+ --q;
+ }
+ qs[0] = q;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ q = (((rem.v64>>2) * recipSqrt32)>>32) + 2;
+ sigZExtra = (uint64_t) ((uint_fast64_t) q<<59);
+ term = softfloat_shortShiftLeft128( 0, qs[1], 53 );
+ sigZ =
+ softfloat_add128(
+ (uint_fast64_t) qs[2]<<18, ((uint_fast64_t) qs[0]<<24) + (q>>5),
+ term.v64, term.v0
+ );
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( (q & 0xF) <= 2 ) {
+ q &= ~3;
+ sigZExtra = (uint64_t) ((uint_fast64_t) q<<59);
+ y = softfloat_shortShiftLeft128( sigZ.v64, sigZ.v0, 6 );
+ y.v0 |= sigZExtra>>58;
+ term = softfloat_sub128( y.v64, y.v0, 0, q );
+ y = softfloat_mul64ByShifted32To128( term.v0, q );
+ term = softfloat_mul64ByShifted32To128( term.v64, q );
+ term = softfloat_add128( term.v64, term.v0, 0, y.v64 );
+ rem = softfloat_shortShiftLeft128( rem.v64, rem.v0, 20 );
+ term = softfloat_sub128( term.v64, term.v0, rem.v64, rem.v0 );
+ /*--------------------------------------------------------------------
+ | The concatenation of `term' and `y.v0' is now the negative remainder
+ | (3 words altogether).
+ *--------------------------------------------------------------------*/
+ if ( term.v64 & UINT64_C( 0x8000000000000000 ) ) {
+ sigZExtra |= 1;
+ } else {
+ if ( term.v64 | term.v0 | y.v0 ) {
+ if ( sigZExtra ) {
+ --sigZExtra;
+ } else {
+ sigZ = softfloat_sub128( sigZ.v64, sigZ.v0, 0, 1 );
+ sigZExtra = ~0;
+ }
+ }
+ }
+ }
+ return softfloat_roundPackToF128( 0, expZ, sigZ.v64, sigZ.v0, sigZExtra );
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ invalid:
+ softfloat_raiseFlags( softfloat_flag_invalid );
+ uiZ.v64 = defaultNaNF128UI64;
+ uiZ.v0 = defaultNaNF128UI0;
+ uiZ:
+ uZ.ui = uiZ;
+ return uZ.f;
+
+}
+
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