Upgrade to SoftFloat 3e

1 files changed, 171 insertions, 0 deletions

diff --git a/softfloat/f16_rem.c b/softfloat/f16_rem.c
new file mode 100644
index 0000000..76a0de6
--- /dev/null
+++ b/softfloat/f16_rem.c
@@ -0,0 +1,171 @@
+
+/*============================================================================
+
+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"
+
+float16_t f16_rem( float16_t a, float16_t b )
+{
+    union ui16_f16 uA;
+    uint_fast16_t uiA;
+    bool signA;
+    int_fast8_t expA;
+    uint_fast16_t sigA;
+    union ui16_f16 uB;
+    uint_fast16_t uiB;
+    int_fast8_t expB;
+    uint_fast16_t sigB;
+    struct exp8_sig16 normExpSig;
+    uint16_t rem;
+    int_fast8_t expDiff;
+    uint_fast16_t q;
+    uint32_t recip32, q32;
+    uint16_t altRem, meanRem;
+    bool signRem;
+    uint_fast16_t uiZ;
+    union ui16_f16 uZ;
+
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    uA.f = a;
+    uiA = uA.ui;
+    signA = signF16UI( uiA );
+    expA  = expF16UI( uiA );
+    sigA  = fracF16UI( uiA );
+    uB.f = b;
+    uiB = uB.ui;
+    expB = expF16UI( uiB );
+    sigB = fracF16UI( uiB );
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    if ( expA == 0x1F ) {
+        if ( sigA || ((expB == 0x1F) && sigB) ) goto propagateNaN;
+        goto invalid;
+    }
+    if ( expB == 0x1F ) {
+        if ( sigB ) goto propagateNaN;
+        return a;
+    }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    if ( ! expB ) {
+        if ( ! sigB ) goto invalid;
+        normExpSig = softfloat_normSubnormalF16Sig( sigB );
+        expB = normExpSig.exp;
+        sigB = normExpSig.sig;
+    }
+    if ( ! expA ) {
+        if ( ! sigA ) return a;
+        normExpSig = softfloat_normSubnormalF16Sig( sigA );
+        expA = normExpSig.exp;
+        sigA = normExpSig.sig;
+    }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    rem = sigA | 0x0400;
+    sigB |= 0x0400;
+    expDiff = expA - expB;
+    if ( expDiff < 1 ) {
+        if ( expDiff < -1 ) return a;
+        sigB <<= 3;
+        if ( expDiff ) {
+            rem <<= 2;
+            q = 0;
+        } else {
+            rem <<= 3;
+            q = (sigB <= rem);
+            if ( q ) rem -= sigB;
+        }
+    } else {
+        recip32 = softfloat_approxRecip32_1( (uint_fast32_t) sigB<<21 );
+        /*--------------------------------------------------------------------
+        | Changing the shift of `rem' here requires also changing the initial
+        | subtraction from `expDiff'.
+        *--------------------------------------------------------------------*/
+        rem <<= 4;
+        expDiff -= 31;
+        /*--------------------------------------------------------------------
+        | The scale of `sigB' affects how many bits are obtained during each
+        | cycle of the loop.  Currently this is 29 bits per loop iteration,
+        | which is believed to be the maximum possible.
+        *--------------------------------------------------------------------*/
+        sigB <<= 3;
+        for (;;) {
+            q32 = (rem * (uint_fast64_t) recip32)>>16;
+            if ( expDiff < 0 ) break;
+            rem = -((uint_fast16_t) q32 * sigB);
+            expDiff -= 29;
+        }
+        /*--------------------------------------------------------------------
+        | (`expDiff' cannot be less than -30 here.)
+        *--------------------------------------------------------------------*/
+        q32 >>= ~expDiff & 31;
+        q = q32;
+        rem = (rem<<(expDiff + 30)) - q * sigB;
+    }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    do {
+        altRem = rem;
+        ++q;
+        rem -= sigB;
+    } while ( ! (rem & 0x8000) );
+    meanRem = rem + altRem;
+    if ( (meanRem & 0x8000) || (! meanRem && (q & 1)) ) rem = altRem;
+    signRem = signA;
+    if ( 0x8000 <= rem ) {
+        signRem = ! signRem;
+        rem = -rem;
+    }
+    return softfloat_normRoundPackToF16( signRem, expB, rem );
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+ propagateNaN:
+    uiZ = softfloat_propagateNaNF16UI( uiA, uiB );
+    goto uiZ;
+ invalid:
+    softfloat_raiseFlags( softfloat_flag_invalid );
+    uiZ = defaultNaNF16UI;
+ uiZ:
+    uZ.ui = uiZ;
+    return uZ.f;
+
+}
+