Upgrade to SoftFloat 3e

1 files changed, 98 insertions, 16 deletions

diff --git a/softfloat/f32_div.c b/softfloat/f32_div.c
index 3bbc126..8d44479 100755..100644
--- a/softfloat/f32_div.c
+++ b/softfloat/f32_div.c
@@ -1,5 +1,38 @@
-// See LICENSE.SoftFloat for license details.
 
+/*============================================================================
+
+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 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>
@@ -23,21 +56,31 @@ float32_t f32_div( float32_t a, float32_t b )
     bool signZ;
     struct exp16_sig32 normExpSig;
     int_fast16_t expZ;
+#ifdef SOFTFLOAT_FAST_DIV64TO32
+    uint_fast64_t sig64A;
+    uint_fast32_t sigZ;
+#else
     uint_fast32_t sigZ;
+    uint_fast64_t rem;
+#endif
     uint_fast32_t uiZ;
     union ui32_f32 uZ;
 
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
     uA.f = a;
     uiA = uA.ui;
     signA = signF32UI( uiA );
-    expA = expF32UI( uiA );
-    sigA = fracF32UI( uiA );
+    expA  = expF32UI( uiA );
+    sigA  = fracF32UI( uiA );
     uB.f = b;
     uiB = uB.ui;
     signB = signF32UI( uiB );
-    expB = expF32UI( uiB );
-    sigB = fracF32UI( uiB );
+    expB  = expF32UI( uiB );
+    sigB  = fracF32UI( uiB );
     signZ = signA ^ signB;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
     if ( expA == 0xFF ) {
         if ( sigA ) goto propagateNaN;
         if ( expB == 0xFF ) {
@@ -50,10 +93,12 @@ float32_t f32_div( float32_t a, float32_t b )
         if ( sigB ) goto propagateNaN;
         goto zero;
     }
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
     if ( ! expB ) {
         if ( ! sigB ) {
-            if ( ! ( expA | sigA ) ) goto invalid;
-            softfloat_raiseFlags( softfloat_flag_infinity );
+            if ( ! (expA | sigA) ) goto invalid;
+            softfloat_raiseFlags( softfloat_flag_infinite );
             goto infinity;
         }
         normExpSig = softfloat_normSubnormalF32Sig( sigB );
@@ -66,28 +111,65 @@ float32_t f32_div( float32_t a, float32_t b )
         expA = normExpSig.exp;
         sigA = normExpSig.sig;
     }
-    expZ = expA - expB + 0x7D;
-    sigA = ( sigA | 0x00800000 )<<7;
-    sigB = ( sigB | 0x00800000 )<<8;
-    if ( sigB <= ( sigA + sigA ) ) {
-        ++expZ;
-        sigA >>= 1;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    expZ = expA - expB + 0x7E;
+    sigA |= 0x00800000;
+    sigB |= 0x00800000;
+#ifdef SOFTFLOAT_FAST_DIV64TO32
+    if ( sigA < sigB ) {
+        --expZ;
+        sig64A = (uint_fast64_t) sigA<<31;
+    } else {
+        sig64A = (uint_fast64_t) sigA<<30;
     }
-    sigZ = ( (uint_fast64_t) sigA<<32 ) / sigB;
-    if ( ! ( sigZ & 0x3F ) ) {
-        sigZ |= ( (uint_fast64_t) sigB * sigZ != (uint_fast64_t) sigA<<32 );
+    sigZ = sig64A / sigB;
+    if ( ! (sigZ & 0x3F) ) sigZ |= ((uint_fast64_t) sigB * sigZ != sig64A);
+#else
+    if ( sigA < sigB ) {
+        --expZ;
+        sigA <<= 8;
+    } else {
+        sigA <<= 7;
+    }
+    sigB <<= 8;
+    sigZ = ((uint_fast64_t) sigA * softfloat_approxRecip32_1( sigB ))>>32;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
+    sigZ += 2;
+    if ( (sigZ & 0x3F) < 2 ) {
+        sigZ &= ~3;
+#ifdef SOFTFLOAT_FAST_INT64
+        rem = ((uint_fast64_t) sigA<<31) - (uint_fast64_t) sigZ * sigB;
+#else
+        rem = ((uint_fast64_t) sigA<<32) - (uint_fast64_t) (sigZ<<1) * sigB;
+#endif
+        if ( rem & UINT64_C( 0x8000000000000000 ) ) {
+            sigZ -= 4;
+        } else {
+            if ( rem ) sigZ |= 1;
+        }
     }
+#endif
     return softfloat_roundPackToF32( signZ, expZ, sigZ );
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
  propagateNaN:
     uiZ = softfloat_propagateNaNF32UI( uiA, uiB );
     goto uiZ;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
  invalid:
     softfloat_raiseFlags( softfloat_flag_invalid );
     uiZ = defaultNaNF32UI;
     goto uiZ;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
  infinity:
     uiZ = packToF32UI( signZ, 0xFF, 0 );
     goto uiZ;
+    /*------------------------------------------------------------------------
+    *------------------------------------------------------------------------*/
  zero:
     uiZ = packToF32UI( signZ, 0, 0 );
  uiZ: