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author | Hans Hagen <pragma@wxs.nl> | 2023-04-27 00:04:07 +0200 |
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committer | Context Git Mirror Bot <phg@phi-gamma.net> | 2023-04-27 00:04:07 +0200 |
commit | 6b25a7a970ba9553adf8077ef2eecb50a5d77818 (patch) | |
tree | f06e40077ba9e55af4bf6cab52313f79f8ea84a8 /source/luametatex/source/libraries/softposit/source/p8_to_pX1.c | |
parent | 657457ef4a08c1f000f272e00f654f4064cc37bd (diff) | |
download | context-6b25a7a970ba9553adf8077ef2eecb50a5d77818.tar.gz |
2023-04-26 23:31:00
Diffstat (limited to 'source/luametatex/source/libraries/softposit/source/p8_to_pX1.c')
-rw-r--r-- | source/luametatex/source/libraries/softposit/source/p8_to_pX1.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/source/luametatex/source/libraries/softposit/source/p8_to_pX1.c b/source/luametatex/source/libraries/softposit/source/p8_to_pX1.c new file mode 100644 index 000000000..84ef367bc --- /dev/null +++ b/source/luametatex/source/libraries/softposit/source/p8_to_pX1.c @@ -0,0 +1,130 @@ +/*============================================================================ + +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. + +This C source file was based on SoftFloat IEEE Floating-Point Arithmetic +Package, Release 3d, 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 "platform.h" +#include "internals.h" + +posit_1_t p8_to_pX1( posit8_t pA, int x ) { + + union ui8_p8 uA; + union ui32_pX1 uZ; + uint_fast8_t uiA, tmp; + uint_fast32_t exp_frac32A=0, regime; + bool sign, regSA; + int_fast8_t kA=0, regA; + + if (x<2 || x>32){ + uZ.ui = 0x80000000; + return uZ.p; + } + + uA.p = pA; + uiA = uA.ui; + + if (uiA==0x80 || uiA==0 ){ + uZ.ui = (uint32_t)uiA<<24; + return uZ.p; + } + + sign = signP8UI( uiA ); + if (sign) uiA = -uiA & 0xFF; + + if(x==2){ + uZ.ui=(uiA>0)?(0x40000000):(0); + } + else{ + regSA = signregP8UI(uiA); + + tmp = (uiA<<2) & 0xFF; + if (regSA){ + while (tmp>>7){ + kA++; + tmp= (tmp<<1) & 0xFF; + } + } + else{ + kA=-1; + while (!(tmp>>7)){ + kA--; + tmp= (tmp<<1) & 0xFF; + } + tmp&=0x7F; + } + exp_frac32A = tmp<<24; + + if(kA<0){ + regA = -kA; + // Place exponent bits + if (regA&0x1) exp_frac32A |= 0x80000000; + + regA = (regA+1)>>1; + if (regA==0) regA=1; + regSA = 0; + regime = 0x40000000>>regA; + } + else{ + if (kA&0x1) exp_frac32A |= 0x80000000; + + regA = (kA+2)>>1; + if (regA==0) regA=1; + regSA=1; + regime = 0x7FFFFFFF - (0x7FFFFFFF>>regA); + } + exp_frac32A >>=(regA+2); //2 because of sign and regime terminating bit + + uZ.ui = regime + exp_frac32A; + + int shift = 32-x; + + if( (uZ.ui>>shift)!=(0x7FFFFFFF>>shift) ){ + if( ((uint32_t)0x80000000>>x) & uZ.ui){ + if ( ( ((uint32_t)0x80000000>>(x-1)) & uZ.ui) || (((uint32_t)0x7FFFFFFF>>x) & uZ.ui) ) + uZ.ui += (0x1<<shift); + } + } + + uZ.ui &=((int32_t)0x80000000>>(x-1)); + if (uZ.ui==0) uZ.ui = 0x1<<shift; + } + + if (sign) uZ.ui = -uZ.ui & 0xFFFFFFFF; + + return uZ.p; +} + |