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diff --git a/source/luametatex/source/libraries/softposit/source/c_convertDecToPosit16.c b/source/luametatex/source/libraries/softposit/source/c_convertDecToPosit16.c
new file mode 100644
index 000000000..86a8383bc
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+++ b/source/luametatex/source/libraries/softposit/source/c_convertDecToPosit16.c
@@ -0,0 +1,447 @@
+/*============================================================================
+
+This C source file is part of the SoftPosit Posit Arithmetic Package
+by S. H. Leong (Cerlane).
+
+Copyright 2017, 2018 A*STAR. 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 <math.h>
+
+#include "platform.h"
+#include "internals.h"
+
+void checkExtraTwoBitsP16(double f16, double temp, bool * bitsNPlusOne, bool * bitsMore ){
+ temp /= 2;
+ if (temp<=f16){
+ *bitsNPlusOne = 1;
+ f16-=temp;
+ }
+ if (f16>0)
+ *bitsMore = 1;
+}
+uint_fast16_t convertFractionP16(double f16, uint_fast8_t fracLength, bool * bitsNPlusOne, bool * bitsMore ){
+
+ uint_fast16_t frac=0;
+
+ if(f16==0) return 0;
+ else if(f16==INFINITY) return 0x8000;
+
+ f16 -= 1; //remove hidden bit
+ if (fracLength==0)
+ checkExtraTwoBitsP16(f16, 1.0, bitsNPlusOne, bitsMore);
+ else{
+ double temp = 1;
+ while (true){
+ temp /= 2;
+ if (temp<=f16){
+ f16-=temp;
+ fracLength--;
+ frac = (frac<<1) + 1; //shift in one
+ if (f16==0){
+ //put in the rest of the bits
+ frac <<= (uint_fast8_t)fracLength;
+ break;
+ }
+
+ if (fracLength == 0){
+ checkExtraTwoBitsP16(f16, temp, bitsNPlusOne, bitsMore);
+
+ break;
+ }
+ }
+ else{
+ frac <<= 1; //shift in a zero
+ fracLength--;
+ if (fracLength == 0){
+ checkExtraTwoBitsP16(f16, temp, bitsNPlusOne, bitsMore);
+ break;
+ }
+ }
+ }
+ }
+
+ return frac;
+}
+posit16_t convertFloatToP16(float a){
+ return convertDoubleToP16((double) a);
+}
+
+posit16_t convertDoubleToP16(double f16){
+ union ui16_p16 uZ;
+ bool sign, regS;
+ uint_fast16_t reg, frac=0;
+ int_fast8_t exp=0;
+ bool bitNPlusOne=0, bitsMore=0;
+
+ (f16>=0) ? (sign=0) : (sign=1);
+
+ if (f16 == 0 ){
+ uZ.ui = 0;
+ return uZ.p;
+ }
+ else if(f16 == INFINITY || f16 == -INFINITY || f16 == NAN){
+ uZ.ui = 0x8000;
+ return uZ.p;
+ }
+ else if (f16 == 1) {
+ uZ.ui = 16384;
+ return uZ.p;
+ }
+ else if (f16 == -1){
+ uZ.ui = 49152;
+ return uZ.p;
+ }
+ else if (f16 >= 268435456){
+ //maxpos
+ uZ.ui = 32767;
+ return uZ.p;
+ }
+ else if (f16 <= -268435456){
+ // -maxpos
+ uZ.ui = 32769;
+ return uZ.p;
+ }
+ else if(f16 <= 3.725290298461914e-9 && !sign){
+ //minpos
+ uZ.ui = 1;
+ return uZ.p;
+ }
+ else if(f16 >= -3.725290298461914e-9 && sign){
+ //-minpos
+ uZ.ui = 65535;
+ return uZ.p;
+ }
+ else if (f16>1 || f16<-1){
+ if (sign){
+ //Make negative numbers positive for easier computation
+ f16 = -f16;
+ }
+
+ regS = 1;
+ reg = 1; //because k = m-1; so need to add back 1
+ // minpos
+ if (f16 <= 3.725290298461914e-9){
+ uZ.ui = 1;
+ }
+ else{
+ //regime
+ while (f16>=4){
+ f16 *=0.25;
+ reg++;
+ }
+ if (f16>=2){
+ f16*=0.5;
+ exp++;
+ }
+
+ int fracLength = 13-reg;
+
+ if (fracLength<0){
+ //reg == 14, means rounding bits is exp and just the rest.
+ if (f16>1) bitsMore = 1;
+
+ }
+ else
+ frac = convertFractionP16 (f16, fracLength, &bitNPlusOne, &bitsMore);
+
+
+ if (reg==14 && frac>0) {
+ bitsMore = 1;
+ frac=0;
+ }
+ if (reg>14)
+ (regS) ? (uZ.ui= 32767): (uZ.ui=0x1);
+ else{
+ uint_fast16_t regime = 1;
+ if (regS) regime = ( (1<<reg)-1 ) <<1;
+ uZ.ui = ((uint16_t) (regime) << (14-reg)) + ((uint16_t) (exp)<< (13-reg)) + ((uint16_t)(frac));
+ //n+1 frac bit is 1. Need to check if another bit is 1 too if not round to even
+ if (reg==14 && exp) bitNPlusOne = 1;
+ uZ.ui += (bitNPlusOne & (uZ.ui&1)) | ( bitNPlusOne & bitsMore);
+ }
+ if (sign) uZ.ui = -uZ.ui & 0xFFFF;
+ }
+ }
+ else if (f16 < 1 || f16 > -1 ){
+
+ if (sign){
+ //Make negative numbers positive for easier computation
+ f16 = -f16;
+ }
+ regS = 0;
+ reg = 0;
+
+ //regime
+ while (f16<1){
+ f16 *= 4;
+ reg++;
+ }
+ if (f16>=2){
+ f16/=2;
+ exp++;
+ }
+ if (reg==14){
+ bitNPlusOne = exp;
+ if (frac>1) bitsMore = 1;
+ }
+ else{
+ //only possible combination for reg=15 to reach here is 7FFF (maxpos) and FFFF (-minpos)
+ //but since it should be caught on top, so no need to handle
+ int_fast8_t fracLength = 13-reg;
+ frac = convertFractionP16 (f16, fracLength, &bitNPlusOne, &bitsMore);
+ }
+
+ if (reg==14 && frac>0) {
+ bitsMore = 1;
+ frac=0;
+ }
+ if (reg>14)
+ (regS) ? (uZ.ui= 32767): (uZ.ui=0x1);
+ else{
+ uint_fast16_t regime = 1;
+ if (regS) regime = ( (1<<reg)-1 ) <<1;
+ uZ.ui = ((uint16_t) (regime) << (14-reg)) + ((uint16_t) (exp)<< (13-reg)) + ((uint16_t)(frac));
+ //n+1 frac bit is 1. Need to check if another bit is 1 too if not round to even
+ if (reg==14 && exp) bitNPlusOne = 1;
+ uZ.ui += (bitNPlusOne & (uZ.ui&1)) | ( bitNPlusOne & bitsMore);
+ }
+ if (sign) uZ.ui = -uZ.ui & 0xFFFF;
+ }
+ else {
+ //NaR - for NaN, INF and all other combinations
+ uZ.ui = 0x8000;
+ }
+ return uZ.p;
+}
+
+
+#ifdef SOFTPOSIT_QUAD
+ void checkQuadExtraTwoBitsP16(__float128 f16, double temp, bool * bitsNPlusOne, bool * bitsMore ){
+ temp /= 2;
+ if (temp<=f16){
+ *bitsNPlusOne = 1;
+ f16-=temp;
+ }
+ if (f16>0)
+ *bitsMore = 1;
+ }
+ uint_fast16_t convertQuadFractionP16(__float128 f16, uint_fast8_t fracLength, bool * bitsNPlusOne, bool * bitsMore ){
+
+ uint_fast16_t frac=0;
+
+ if(f16==0) return 0;
+ else if(f16==INFINITY) return 0x8000;
+
+ f16 -= 1; //remove hidden bit
+ if (fracLength==0)
+ checkQuadExtraTwoBitsP16(f16, 1.0, bitsNPlusOne, bitsMore);
+ else{
+ __float128 temp = 1;
+ while (true){
+ temp /= 2;
+ if (temp<=f16){
+ f16-=temp;
+ fracLength--;
+ frac = (frac<<1) + 1; //shift in one
+ if (f16==0){
+ //put in the rest of the bits
+ frac <<= (uint_fast8_t)fracLength;
+ break;
+ }
+
+ if (fracLength == 0){
+ checkQuadExtraTwoBitsP16(f16, temp, bitsNPlusOne, bitsMore);
+
+ break;
+ }
+ }
+ else{
+ frac <<= 1; //shift in a zero
+ fracLength--;
+ if (fracLength == 0){
+ checkQuadExtraTwoBitsP16(f16, temp, bitsNPlusOne, bitsMore);
+ break;
+ }
+ }
+ }
+ }
+
+ return frac;
+ }
+
+
+ posit16_t convertQuadToP16(__float128 f16){
+ union ui16_p16 uZ;
+ bool sign, regS;
+ uint_fast16_t reg, frac=0;
+ int_fast8_t exp=0;
+ bool bitNPlusOne=0, bitsMore=0;
+
+ (f16>=0) ? (sign=0) : (sign=1);
+
+ if (f16 == 0 ){
+ uZ.ui = 0;
+ return uZ.p;
+ }
+ else if(f16 == INFINITY || f16 == -INFINITY || f16 == NAN){
+ uZ.ui = 0x8000;
+ return uZ.p;
+ }
+ else if (f16 == 1) {
+ uZ.ui = 16384;
+ return uZ.p;
+ }
+ else if (f16 == -1){
+ uZ.ui = 49152;
+ return uZ.p;
+ }
+ else if (f16 >= 268435456){
+ //maxpos
+ uZ.ui = 32767;
+ return uZ.p;
+ }
+ else if (f16 <= -268435456){
+ // -maxpos
+ uZ.ui = 32769;
+ return uZ.p;
+ }
+ else if(f16 <= 3.725290298461914e-9 && !sign){
+ //minpos
+ uZ.ui = 1;
+ return uZ.p;
+ }
+ else if(f16 >= -3.725290298461914e-9 && sign){
+ //-minpos
+ uZ.ui = 65535;
+ return uZ.p;
+ }
+ else if (f16>1 || f16<-1){
+ if (sign){
+ //Make negative numbers positive for easier computation
+ f16 = -f16;
+ }
+ regS = 1;
+ reg = 1; //because k = m-1; so need to add back 1
+ // minpos
+ if (f16 <= 3.725290298461914e-9){
+ uZ.ui = 1;
+ }
+ else{
+ //regime
+ while (f16>=4){
+ f16 *=0.25;
+ reg++;
+ }
+ if (f16>=2){
+ f16*=0.5;
+ exp++;
+ }
+
+ int8_t fracLength = 13-reg;
+ if (fracLength<0){
+ //reg == 14, means rounding bits is exp and just the rest.
+ if (f16>1) bitsMore = 1;
+ }
+ else
+ frac = convertQuadFractionP16 (f16, fracLength, &bitNPlusOne, &bitsMore);
+
+ if (reg==14 && frac>0) {
+ bitsMore = 1;
+ frac=0;
+ }
+
+ if (reg>14)
+ (regS) ? (uZ.ui= 32767): (uZ.ui=0x1);
+ else{
+ uint_fast16_t regime = 1;
+ if (regS) regime = ( (1<<reg)-1 ) <<1;
+ uZ.ui = ((uint16_t) (regime) << (14-reg)) + ((uint16_t) (exp)<< (13-reg)) + ((uint16_t)(frac));
+ //n+1 frac bit is 1. Need to check if another bit is 1 too if not round to even
+ if (reg==14 && exp) bitNPlusOne = 1;
+ uZ.ui += (bitNPlusOne & (uZ.ui&1)) | ( bitNPlusOne & bitsMore);
+ }
+ if (sign) uZ.ui = -uZ.ui & 0xFFFF;
+ }
+ }
+ else if (f16 < 1 || f16 > -1 ){
+ if (sign){
+ //Make negative numbers positive for easier computation
+ f16 = -f16;
+ }
+ regS = 0;
+ reg = 0;
+
+ //regime
+ while (f16<1){
+ f16 *= 4;
+ reg++;
+ }
+ if (f16>=2){
+ f16/=2;
+ exp++;
+ }
+ if (reg==14){
+ bitNPlusOne = exp;
+ if (frac>1) bitsMore = 1;
+ }
+ else{
+ //only possible combination for reg=15 to reach here is 7FFF (maxpos) and FFFF (-minpos)
+ //but since it should be caught on top, so no need to handle
+ int_fast8_t fracLength = 13-reg;
+ frac = convertQuadFractionP16 (f16, fracLength, &bitNPlusOne, &bitsMore);
+ }
+
+ if (reg==14 && frac>0) {
+ bitsMore = 1;
+ frac=0;
+ }
+ if (reg>14)
+ (regS) ? (uZ.ui= 32767): (uZ.ui=0x1);
+ else{
+ uint_fast16_t regime = 1;
+ if (regS) regime = ( (1<<reg)-1 ) <<1;
+ uZ.ui = ((uint16_t) (regime) << (14-reg)) + ((uint16_t) (exp)<< (13-reg)) + ((uint16_t)(frac));
+ //n+1 frac bit is 1. Need to check if another bit is 1 too if not round to even
+ if (reg==14 && exp) bitNPlusOne = 1;
+ uZ.ui += (bitNPlusOne & (uZ.ui&1)) | ( bitNPlusOne & bitsMore);
+ }
+ if (sign) uZ.ui = -uZ.ui & 0xFFFF;
+
+ }
+ else {
+ //NaR - for NaN, INF and all other combinations
+ uZ.ui = 0x8000;
+ }
+ return uZ.p;
+ }
+#endif
+
+
+
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