First draft of RC for Release 3, to start review process.

1 files changed, 189 insertions, 0 deletions

diff --git a/source/f128_rem.c b/source/f128_rem.c
new file mode 100644
index 0000000..dafe05b
--- /dev/null
+++ b/source/f128_rem.c
@@ -0,0 +1,189 @@
+
+/*============================================================================
+
+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 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"
+
+float128_t f128_rem( float128_t a, float128_t b )
+{
+    union ui128_f128 uA;
+    uint_fast64_t uiA64, uiA0;
+    bool signA;
+    int_fast32_t expA;
+    struct uint128 sigA;
+    union ui128_f128 uB;
+    uint_fast64_t uiB64, uiB0;
+    bool signB;
+    int_fast32_t expB;
+    struct uint128 sigB;
+    struct exp32_sig128 normExpSig;
+    struct uint128 rem;
+    int_fast32_t expDiff;
+    uint_fast32_t q, recip32;
+    uint_fast64_t q64;
+    struct uint128 term, altRem, meanRem;
+    bool signRem;
+    struct uint128 uiZ;
+    union ui128_f128 uZ;
+
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    uA.f = a;
+    uiA64 = uA.ui.v64;
+    uiA0  = uA.ui.v0;
+    signA = signF128UI64( uiA64 );
+    expA  = expF128UI64( uiA64 );
+    sigA.v64 = fracF128UI64( uiA64 );
+    sigA.v0  = uiA0;
+    uB.f = b;
+    uiB64 = uB.ui.v64;
+    uiB0  = uB.ui.v0;
+    signB = signF128UI64( uiB64 );
+    expB  = expF128UI64( uiB64 );
+    sigB.v64 = fracF128UI64( uiB64 );
+    sigB.v0  = uiB0;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    if ( expA == 0x7FFF ) {
+        if (
+            (sigA.v64 | sigA.v0) || ((expB == 0x7FFF) && (sigB.v64 | sigB.v0))
+        ) {
+            goto propagateNaN;
+        }
+        goto invalid;
+    }
+    if ( expB == 0x7FFF ) {
+        if ( sigB.v64 | sigB.v0 ) goto propagateNaN;
+        return a;
+    }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    if ( ! expB ) {
+        if ( ! (sigB.v64 | sigB.v0) ) goto invalid;
+        normExpSig = softfloat_normSubnormalF128Sig( sigB.v64, sigB.v0 );
+        expB = normExpSig.exp;
+        sigB = normExpSig.sig;
+    }
+    if ( ! expA ) {
+        if ( ! (sigA.v64 | sigA.v0) ) return a;
+        normExpSig = softfloat_normSubnormalF128Sig( sigA.v64, sigA.v0 );
+        expA = normExpSig.exp;
+        sigA = normExpSig.sig;
+    }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    sigA.v64 |= UINT64_C( 0x0001000000000000 );
+    sigB.v64 |= UINT64_C( 0x0001000000000000 );
+    rem = sigA;
+    expDiff = expA - expB;
+    if ( expDiff < 1 ) {
+        if ( expDiff < -1 ) return a;
+        if ( expDiff ) {
+            --expB;
+            sigB = softfloat_add128( sigB.v64, sigB.v0, sigB.v64, sigB.v0 );
+            q = 0;
+        } else {
+            q = softfloat_le128( sigB.v64, sigB.v0, rem.v64, rem.v0 );
+            if ( q ) {
+                rem = softfloat_sub128( rem.v64, rem.v0, sigB.v64, sigB.v0 );
+            }
+        }
+    } else {
+        recip32 = softfloat_approxRecip32_1( sigB.v64>>17 );
+        expDiff -= 30;
+        for (;;) {
+            q64 = (uint_fast64_t) (uint32_t) (rem.v64>>19) * recip32;
+            if ( expDiff < 0 ) break;
+            q = (q64 + 0x80000000)>>32;
+            rem = softfloat_shortShiftLeft128( rem.v64, rem.v0, 29 );
+            term = softfloat_mul128By32( sigB.v64, sigB.v0, q );
+            rem = softfloat_sub128( rem.v64, rem.v0, term.v64, term.v0 );
+            if ( rem.v64 & UINT64_C( 0x8000000000000000 ) ) {
+                rem = softfloat_add128( rem.v64, rem.v0, sigB.v64, sigB.v0 );
+            }
+            expDiff -= 29;
+        }
+        /*--------------------------------------------------------------------
+        | (`expDiff' cannot be less than -29 here.)
+        *--------------------------------------------------------------------*/
+        q = (uint32_t) (q64>>32)>>(~expDiff & 31);
+        rem = softfloat_shortShiftLeft128( rem.v64, rem.v0, expDiff + 30 );
+        term = softfloat_mul128By32( sigB.v64, sigB.v0, q );
+        rem = softfloat_sub128( rem.v64, rem.v0, term.v64, term.v0 );
+        if ( rem.v64 & UINT64_C( 0x8000000000000000 ) ) {
+            altRem = softfloat_add128( rem.v64, rem.v0, sigB.v64, sigB.v0 );
+            goto selectRem;
+        }
+    }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    do {
+        altRem = rem;
+        ++q;
+        rem = softfloat_sub128( rem.v64, rem.v0, sigB.v64, sigB.v0 );
+    } while ( ! (rem.v64 & UINT64_C( 0x8000000000000000 )) );
+ selectRem:
+    meanRem = softfloat_add128( rem.v64, rem.v0, altRem.v64, altRem.v0 );
+    if (
+        (meanRem.v64 & UINT64_C( 0x8000000000000000 ))
+            || (! (meanRem.v64 | meanRem.v0) && (q & 1))
+    ) {
+        rem = altRem;
+    }
+    signRem = signA;
+    if ( rem.v64 & UINT64_C( 0x8000000000000000 ) ) {
+        signRem = ! signRem;
+        rem = softfloat_sub128( 0, 0, rem.v64, rem.v0 );
+    }
+    return softfloat_normRoundPackToF128( signRem, expB - 1, rem.v64, rem.v0 );
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+ propagateNaN:
+    uiZ = softfloat_propagateNaNF128UI( uiA64, uiA0, uiB64, uiB0 );
+    goto uiZ;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+ invalid:
+    softfloat_raiseFlags( softfloat_flag_invalid );
+    uiZ.v64 = defaultNaNF128UI64;
+    uiZ.v0  = defaultNaNF128UI0;
+ uiZ:
+    uZ.ui = uiZ;
+    return uZ.f;
+
+}
+