diff options
Diffstat (limited to 'src/libs/softfloat-3e/source/f32_sqrt.c')
-rw-r--r-- | src/libs/softfloat-3e/source/f32_sqrt.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/src/libs/softfloat-3e/source/f32_sqrt.c b/src/libs/softfloat-3e/source/f32_sqrt.c new file mode 100644 index 00000000..ff5e169a --- /dev/null +++ b/src/libs/softfloat-3e/source/f32_sqrt.c @@ -0,0 +1,121 @@ + +/*============================================================================ + +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 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" + +float32_t f32_sqrt( float32_t a SOFTFLOAT_STATE_DECL_COMMA ) +{ + union ui32_f32 uA; + uint_fast32_t uiA; + bool signA; + int_fast16_t expA; + uint_fast32_t sigA, uiZ; + struct exp16_sig32 normExpSig; + int_fast16_t expZ; + uint_fast32_t sigZ, shiftedSigZ; + uint32_t negRem; + union ui32_f32 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uA.f = a; + uiA = uA.ui; + signA = signF32UI( uiA ); + expA = expF32UI( uiA ); + sigA = fracF32UI( uiA ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( expA == 0xFF ) { + if ( sigA ) { + uiZ = softfloat_propagateNaNF32UI( uiA, 0 SOFTFLOAT_STATE_ARG_COMMA ); + goto uiZ; + } + if ( ! signA ) return a; + goto invalid; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( signA ) { + if ( ! (expA | sigA) ) return a; + goto invalid; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( ! expA ) { + if ( ! sigA ) return a; + normExpSig = softfloat_normSubnormalF32Sig( sigA ); + expA = normExpSig.exp; + sigA = normExpSig.sig; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + expZ = ((expA - 0x7F)>>1) + 0x7E; + expA &= 1; + sigA = (sigA | 0x00800000)<<8; + sigZ = + ((uint_fast64_t) sigA * softfloat_approxRecipSqrt32_1( expA, sigA )) + >>32; + if ( expA ) sigZ >>= 1; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + sigZ += 2; + if ( (sigZ & 0x3F) < 2 ) { + shiftedSigZ = sigZ>>2; + negRem = shiftedSigZ * shiftedSigZ; + sigZ &= ~3; + if ( negRem & 0x80000000 ) { + sigZ |= 1; + } else { + if ( negRem ) --sigZ; + } + } + return softfloat_roundPackToF32( 0, expZ, sigZ SOFTFLOAT_STATE_ARG_COMMA ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + invalid: + softfloat_raiseFlags( softfloat_flag_invalid SOFTFLOAT_STATE_ARG_COMMA ); + uiZ = defaultNaNF32UI; + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |