Upgrade to latest SoftFloat

1 files changed, 133 insertions, 74 deletions

diff --git a/softfloat/f64_sqrt.c b/softfloat/f64_sqrt.c
index cd91010..b65c150 100755..100644
--- a/softfloat/f64_sqrt.c
+++ b/softfloat/f64_sqrt.c
@@ -1,74 +1,133 @@
-

-#include <stdbool.h>

-#include <stdint.h>

-#include "platform.h"

-#include "primitives.h"

-#include "internals.h"

-#include "specialize.h"

-#include "softfloat.h"

-

-float64_t f64_sqrt( float64_t a )

-{

-    union ui64_f64 uA;

-    uint_fast64_t uiA;

-    bool signA;

-    int_fast16_t expA;

-    uint_fast64_t sigA, uiZ;

-    struct exp16_sig64 normExpSig;

-    int_fast16_t expZ;

-    uint_fast32_t sigZ32;

-    uint_fast64_t sigZ;

-    struct uint128 term, rem;

-    union ui64_f64 uZ;

-

-    uA.f = a;

-    uiA = uA.ui;

-    signA = signF64UI( uiA );

-    expA = expF64UI( uiA );

-    sigA = fracF64UI( uiA );

-    if ( expA == 0x7FF ) {

-        if ( sigA ) {

-            uiZ = softfloat_propagateNaNF64UI( uiA, 0 );

-            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_normSubnormalF64Sig( sigA );

-        expA = normExpSig.exp;

-        sigA = normExpSig.sig;

-    }

-    expZ = ( ( expA - 0x3FF )>>1 ) + 0x3FE;

-    sigA |= UINT64_C( 0x0010000000000000 );

-    sigZ32 = softfloat_estimateSqrt32( expA, sigA>>21 );

-    sigA <<= 9 - ( expA & 1 );

-    sigZ =

-        softfloat_estimateDiv128To64( sigA, 0, (uint_fast64_t) sigZ32<<32 )

-            + ( (uint_fast64_t) sigZ32<<30 );

-    if ( ( sigZ & 0x1FF ) <= 5 ) {

-        term = softfloat_mul64To128( sigZ, sigZ );

-        rem = softfloat_sub128( sigA, 0, term.v64, term.v0 );

-        while ( UINT64_C( 0x8000000000000000 ) <= rem.v64 ) {

-            --sigZ;

-            rem =

-                softfloat_add128(

-                    rem.v64, rem.v0, sigZ>>63, (uint64_t) ( sigZ<<1 ) );

-        }

-        sigZ |= ( ( rem.v64 | rem.v0 ) != 0 );

-    }

-    return softfloat_roundPackToF64( 0, expZ, sigZ );

- invalid:

-    softfloat_raiseFlags( softfloat_flag_invalid );

-    uiZ = defaultNaNF64UI;

- uiZ:

-    uZ.ui = uiZ;

-    return uZ.f;

-

-}

-

+
+/*============================================================================
+
+This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
+Package, Release 3a, by John R. Hauser.
+
+Copyright 2011, 2012, 2013, 2014 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"
+
+float64_t f64_sqrt( float64_t a )
+{
+    union ui64_f64 uA;
+    uint_fast64_t uiA;
+    bool signA;
+    int_fast16_t expA;
+    uint_fast64_t sigA, uiZ;
+    struct exp16_sig64 normExpSig;
+    int_fast16_t expZ;
+    uint32_t sig32A, recipSqrt32, sig32Z;
+    uint_fast64_t rem;
+    uint32_t q;
+    uint_fast64_t sigZ, shiftedSigZ;
+    union ui64_f64 uZ;
+
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    uA.f = a;
+    uiA = uA.ui;
+    signA = signF64UI( uiA );
+    expA  = expF64UI( uiA );
+    sigA  = fracF64UI( uiA );
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    if ( expA == 0x7FF ) {
+        if ( sigA ) {
+            uiZ = softfloat_propagateNaNF64UI( uiA, 0 );
+            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_normSubnormalF64Sig( sigA );
+        expA = normExpSig.exp;
+        sigA = normExpSig.sig;
+    }
+    /*------------------------------------------------------------------------
+    | (`sig32Z' is guaranteed to be a lower bound on the square root of
+    | `sig32A', which makes `sig32Z' also a lower bound on the square root of
+    | `sigA'.)
+    *------------------------------------------------------------------------*/
+    expZ = ((expA - 0x3FF)>>1) + 0x3FE;
+    expA &= 1;
+    sigA |= UINT64_C( 0x0010000000000000 );
+    sig32A = sigA>>21;
+    recipSqrt32 = softfloat_approxRecipSqrt32_1( expA, sig32A );
+    sig32Z = ((uint_fast64_t) sig32A * recipSqrt32)>>32;
+    if ( expA ) {
+        sigA <<= 8;
+        sig32Z >>= 1;
+    } else {
+        sigA <<= 9;
+    }
+    rem = sigA - (uint_fast64_t) sig32Z * sig32Z;
+    q = ((uint32_t) (rem>>2) * (uint_fast64_t) recipSqrt32)>>32;
+    sigZ = ((uint_fast64_t) sig32Z<<32 | 1<<5) + ((uint_fast64_t) q<<3);
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    if ( (sigZ & 0x1FF) < 1<<5 ) {
+        sigZ &= ~(uint_fast64_t) 0x3F;
+        shiftedSigZ = sigZ>>6;
+        rem = (sigA<<52) - shiftedSigZ * shiftedSigZ;
+        if ( rem & UINT64_C( 0x8000000000000000 ) ) {
+            --sigZ;
+        } else {
+            if ( rem ) sigZ |= 1;
+        }
+    }
+    return softfloat_roundPackToF64( 0, expZ, sigZ );
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+ invalid:
+    softfloat_raiseFlags( softfloat_flag_invalid );
+    uiZ = defaultNaNF64UI;
+ uiZ:
+    uZ.ui = uiZ;
+    return uZ.f;
+
+}
+