/*============================================================================

This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
Package, Release 3, by John R. Hauser.

Copyright 2011, 2012, 2013, 2014, 2015 The Regents of the University of
California (Regents).  All Rights Reserved.  Redistribution and use in source
and binary forms, with or without modification, are permitted provided that
the following conditions are met:

Redistributions of source code must retain the above copyright notice,
this list of conditions, and the following two paragraphs of disclaimer.
Redistributions in binary form must reproduce the above copyright notice,
this list of conditions, and the following two paragraphs of disclaimer in the
documentation and/or other materials provided with the distribution.  Neither
the name of the Regents nor the names of its contributors may be used to
endorse or promote products derived from this software without specific prior
written permission.

IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
HEREUNDER IS PROVIDED "AS IS".  REGENTS HAS NO OBLIGATION TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

=============================================================================*/

#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "internals.h"
#include "specialize.h"
#include "softfloat.h"

void
 softfloat_mulAddF128M(
     const uint32_t *aWPtr,
     const uint32_t *bWPtr,
     const uint32_t *cWPtr,
     uint32_t *zWPtr,
     uint_fast8_t op
 )
{
    uint32_t uiA96;
    int32_t expA;
    uint32_t uiB96;
    int32_t expB;
    uint32_t uiC96;
    bool signC;
    int32_t expC;
    bool signProd, prodIsInfinite;
    uint32_t *ptr, uiZ96, sigA[4];
    uint_fast8_t shiftCount;
    uint32_t sigX[5];
    int32_t expProd;
    uint32_t sigProd[8], wordSig;
    bool doSub;
    uint_fast8_t
     (*addCarryMRoutinePtr)(
         uint_fast8_t,
         const uint32_t *,
         const uint32_t *,
         uint_fast8_t,
         uint32_t *
     );
    int32_t expDiff;
    bool signZ;
    int32_t expZ;
    uint32_t *extSigPtr;
    uint_fast8_t carry;
    void (*roundPackRoutinePtr)( bool, int32_t, uint32_t *, uint32_t * );

    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
    uiA96 = aWPtr[indexWordHi( 4 )];
    expA = expF128UI96( uiA96 );
    uiB96 = bWPtr[indexWordHi( 4 )];
    expB = expF128UI96( uiB96 );
    uiC96 = cWPtr[indexWordHi( 4 )];
    signC = signF128UI96( uiC96 ) ^ (op == softfloat_mulAdd_subC);
    expC = expF128UI96( uiC96 );
    signProd =
        signF128UI96( uiA96 ) ^ signF128UI96( uiB96 )
            ^ (op == softfloat_mulAdd_subProd);
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
    prodIsInfinite = false;
    if ( (expA == 0x7FFF) || (expB == 0x7FFF) ) {
        if ( softfloat_tryPropagateNaNF128M( aWPtr, bWPtr, zWPtr ) ) {
            goto propagateNaN_ZC;
        }
        ptr = (uint32_t *) aWPtr;
        if ( ! (uint32_t) (uiA96<<1) ) goto possibleInvalidProd;
        if ( ! (uint32_t) (uiB96<<1) ) {
            ptr = (uint32_t *) bWPtr;
     possibleInvalidProd:
            if (
                ! (ptr[indexWord( 4, 2 )] | ptr[indexWord( 4, 1 )]
                       | ptr[indexWord( 4, 0 )])
            ) {
                goto invalid;
            }
        }
        prodIsInfinite = true;
    }
    if ( expC == 0x7FFF ) {
        if (
            fracF128UI96( uiC96 )
                || (cWPtr[indexWord( 4, 2 )] | cWPtr[indexWord( 4, 1 )]
                        | cWPtr[indexWord( 4, 0 )])
        ) {
            zWPtr[indexWordHi( 4 )] = 0;
            goto propagateNaN_ZC;
        }
        if ( prodIsInfinite && (signProd != signC) ) goto invalid;
        goto copyC;
    }
    if ( prodIsInfinite ) {
        uiZ96 = packToF128UI96( signProd, 0x7FFF, 0 );
        goto uiZ;
    }
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
    if ( expA ) {
        sigA[indexWordHi( 4 )] = fracF128UI96( uiA96 ) | 0x00010000;
        sigA[indexWord( 4, 2 )] = aWPtr[indexWord( 4, 2 )];
        sigA[indexWord( 4, 1 )] = aWPtr[indexWord( 4, 1 )];
        sigA[indexWord( 4, 0 )] = aWPtr[indexWord( 4, 0 )];
    } else {
        expA = softfloat_shiftNormSigF128M( aWPtr, 0, sigA );
        if ( expA == -128 ) goto zeroProd;
    }
    if ( expB ) {
        sigX[indexWordHi( 4 )] = fracF128UI96( uiB96 ) | 0x00010000;
        sigX[indexWord( 4, 2 )] = bWPtr[indexWord( 4, 2 )];
        sigX[indexWord( 4, 1 )] = bWPtr[indexWord( 4, 1 )];
        sigX[indexWord( 4, 0 )] = bWPtr[indexWord( 4, 0 )];
    } else {
        expB = softfloat_shiftNormSigF128M( bWPtr, 0, sigX );
        if ( expB == -128 ) goto zeroProd;
    }
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
    expProd = expA + expB - 0x3FF0;
    softfloat_mul128MTo256M( sigA, sigX, sigProd );
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
    wordSig = fracF128UI96( uiC96 );
    if ( expC ) {
        --expC;
        wordSig |= 0x00010000;
    }
    sigX[indexWordHi( 5 )] = wordSig;
    sigX[indexWord( 5, 3 )] = cWPtr[indexWord( 4, 2 )];
    sigX[indexWord( 5, 2 )] = cWPtr[indexWord( 4, 1 )];
    sigX[indexWord( 5, 1 )] = cWPtr[indexWord( 4, 0 )];
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
    doSub = (signProd != signC);
    addCarryMRoutinePtr =
        doSub ? softfloat_addComplCarryM : softfloat_addCarryM;
    expDiff = expProd - expC;
    if ( expDiff <= 0 ) {
        /*--------------------------------------------------------------------
        *--------------------------------------------------------------------*/
        signZ = signC;
        expZ = expC;
        if (
            sigProd[indexWord( 8, 2 )]
                || (sigProd[indexWord( 8, 1 )] | sigProd[indexWord( 8, 0 )])
        ) {
            sigProd[indexWord( 8, 3 )] |= 1;
        }
        extSigPtr = &sigProd[indexMultiwordHi( 8, 5 )];
        if ( expDiff ) {
            softfloat_shiftRightJam160M( extSigPtr, -expDiff, extSigPtr );
        }
        carry = 0;
        if ( doSub ) {
            wordSig = extSigPtr[indexWordLo( 5 )];
            extSigPtr[indexWordLo( 5 )] = -wordSig;
            carry = ! wordSig;
        }
        (*addCarryMRoutinePtr)(
            4,
            &sigX[indexMultiwordHi( 5, 4 )],
            extSigPtr + indexMultiwordHi( 5, 4 ),
            carry,
            extSigPtr + indexMultiwordHi( 5, 4 )
        );
        wordSig = extSigPtr[indexWordHi( 5 )];
        if ( ! expZ ) {
            if ( wordSig & 0x80000000 ) {
                signZ = ! signZ;
                softfloat_negX160M( extSigPtr );
                wordSig = extSigPtr[indexWordHi( 5 )];
            }
            goto checkCancellation;
        }
        if ( wordSig < 0x00010000 ) {
            --expZ;
            softfloat_add160M( extSigPtr, extSigPtr, extSigPtr );
            goto roundPack;
        }
        goto extSigReady_noCancellation;
    } else {
        /*--------------------------------------------------------------------
        *--------------------------------------------------------------------*/
        signZ = signProd;
        expZ = expProd;
        sigX[indexWordLo( 5 )] = 0;
        expDiff -= 128;
        if ( 0 <= expDiff ) {
            /*----------------------------------------------------------------
            *----------------------------------------------------------------*/
            if ( expDiff ) softfloat_shiftRightJam160M( sigX, expDiff, sigX );
            wordSig = sigX[indexWordLo( 5 )];
            carry = 0;
            if ( doSub ) {
                carry = ! wordSig;
                wordSig = -wordSig;
            }
            carry =
                (*addCarryMRoutinePtr)(
                    4,
                    &sigProd[indexMultiwordLo( 8, 4 )],
                    &sigX[indexMultiwordHi( 5, 4 )],
                    carry,
                    &sigProd[indexMultiwordLo( 8, 4 )]
                );
            sigProd[indexWord( 8, 2 )] |= wordSig;
            ptr = &sigProd[indexWord( 8, 4 )];
        } else {
            /*----------------------------------------------------------------
            *----------------------------------------------------------------*/
            shiftCount = expDiff & 31;
            if ( shiftCount ) {
                softfloat_shortShiftRight160M( sigX, shiftCount, sigX );
            }
            expDiff >>= 5;
            extSigPtr =
                &sigProd[indexMultiwordLo( 8, 5 )] - wordIncr
                    + expDiff * -wordIncr;
            carry =
                (*addCarryMRoutinePtr)( 5, extSigPtr, sigX, doSub, extSigPtr );
            if ( expDiff == -4 ) {
                /*------------------------------------------------------------
                *------------------------------------------------------------*/
                wordSig = sigProd[indexWordHi( 8 )];
                if ( wordSig & 0x80000000 ) {
                    signZ = ! signZ;
                    softfloat_negX256M( sigProd );
                    wordSig = sigProd[indexWordHi( 8 )];
                }
                /*------------------------------------------------------------
                *------------------------------------------------------------*/
                if ( wordSig ) goto expProdBigger_noWordShift;
                wordSig = sigProd[indexWord( 8, 6 )];
                if ( 0x00040000 <= wordSig ) goto expProdBigger_noWordShift;
                expZ -= 32;
                extSigPtr = &sigProd[indexMultiwordHi( 8, 5 )] - wordIncr;
                for (;;) {
                    if ( wordSig ) break;
                    wordSig = extSigPtr[indexWord( 5, 3 )];
                    if ( 0x00040000 <= wordSig ) break;
                    expZ -= 32;
                    extSigPtr -= wordIncr;
                    if ( extSigPtr == &sigProd[indexMultiwordLo( 8, 5 )] ) {
                        goto checkCancellation;
                    }
                }
                /*------------------------------------------------------------
                *------------------------------------------------------------*/
                ptr = extSigPtr + indexWordLo( 5 );
                do {
                    ptr -= wordIncr;
                    if ( *ptr ) {
                        extSigPtr[indexWordLo( 5 )] |= 1;
                        break;
                    }
                } while ( ptr != &sigProd[indexWordLo( 8 )] );
                wordSig = extSigPtr[indexWordHi( 5 )];
                goto extSigReady;
            }
            ptr = extSigPtr + indexWordHi( 5 ) + wordIncr;
        }
        /*--------------------------------------------------------------------
        *--------------------------------------------------------------------*/
        if ( carry != doSub ) {
            if ( doSub ) {
                do {
                    wordSig = *ptr;
                    *ptr = wordSig - 1;
                    ptr += wordIncr;
                } while ( ! wordSig );
            } else {
                do {
                    wordSig = *ptr + 1;
                    *ptr = wordSig;
                    ptr += wordIncr;
                } while ( ! wordSig );
            }
        }
        /*--------------------------------------------------------------------
        *--------------------------------------------------------------------*/
     expProdBigger_noWordShift:
        if (
            sigProd[indexWord( 8, 2 )]
                || (sigProd[indexWord( 8, 1 )] | sigProd[indexWord( 8, 0 )])
        ) {
            sigProd[indexWord( 8, 3 )] |= 1;
        }
        extSigPtr = &sigProd[indexMultiwordHi( 8, 5 )];
        wordSig = extSigPtr[indexWordHi( 5 )];
    }
 extSigReady:
    roundPackRoutinePtr = softfloat_normRoundPackMToF128M;
    if ( wordSig < 0x00010000 ) goto doRoundPack;
 extSigReady_noCancellation:
    if ( 0x00020000 <= wordSig ) {
        ++expZ;
        softfloat_shortShiftRightJam160M( extSigPtr, 1, extSigPtr );
    }
 roundPack:
    roundPackRoutinePtr = softfloat_roundPackMToF128M;
 doRoundPack:
    (*roundPackRoutinePtr)( signZ, expZ, extSigPtr, zWPtr );
    return;
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
 invalid:
    softfloat_invalidF128M( zWPtr );
 propagateNaN_ZC:
    softfloat_propagateNaNF128M( zWPtr, cWPtr, zWPtr );
    return;
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
 zeroProd:
    if (
        ! (uint32_t) (uiC96<<1) && (signProd != signC)
            && ! cWPtr[indexWord( 4, 2 )]
            && ! (cWPtr[indexWord( 4, 1 )] | cWPtr[indexWord( 4, 0 )])
    ) {
        goto completeCancellation;
    }
 copyC:
    zWPtr[indexWordHi( 4 )] = uiC96;
    zWPtr[indexWord( 4, 2 )] = cWPtr[indexWord( 4, 2 )];
    zWPtr[indexWord( 4, 1 )] = cWPtr[indexWord( 4, 1 )];
    zWPtr[indexWord( 4, 0 )] = cWPtr[indexWord( 4, 0 )];
    return;
    /*------------------------------------------------------------------------
    *------------------------------------------------------------------------*/
 checkCancellation:
    if (
        wordSig
            || (extSigPtr[indexWord( 5, 3 )] | extSigPtr[indexWord( 5, 2 )])
            || (extSigPtr[indexWord( 5, 1 )] | extSigPtr[indexWord( 5, 0 )])
    ) {
        goto extSigReady;
    }
 completeCancellation:
    uiZ96 =
        packToF128UI96(
            (softfloat_roundingMode == softfloat_round_min), 0, 0 );
 uiZ:
    zWPtr[indexWordHi( 4 )] = uiZ96;
    zWPtr[indexWord( 4, 2 )] = 0;
    zWPtr[indexWord( 4, 1 )] = 0;
    zWPtr[indexWord( 4, 0 )] = 0;

}