Update SoftFloat

[riscv-isa-sim.git] / softfloat / i32_to_f16.c

diff --git a/softfloat/i32_to_f16.c b/softfloat/i32_to_f16.c
new file mode 100644 (file)
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+++ b/softfloat/i32_to_f16.c
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+
+/*============================================================================
+
+This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
+Package, Release 3d, 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 "softfloat.h"
+
+float16_t i32_to_f16( int32_t a )
+{
+    bool sign;
+    uint_fast32_t absA;
+    int_fast8_t shiftDist;
+    union ui16_f16 u;
+    uint_fast16_t sig;
+
+    sign = (a < 0);
+    absA = sign ? -(uint_fast32_t) a : (uint_fast32_t) a;
+    shiftDist = softfloat_countLeadingZeros32( absA ) - 21;
+    if ( 0 <= shiftDist ) {
+        u.ui =
+            a ? packToF16UI(
+                    sign, 0x18 - shiftDist, (uint_fast16_t) absA<<shiftDist )
+                : 0;
+        return u.f;
+    } else {
+        shiftDist += 4;
+        sig =
+            (shiftDist < 0)
+                ? absA>>(-shiftDist)
+                      | ((uint32_t) (absA<<(shiftDist & 31)) != 0)
+                : (uint_fast16_t) absA<<shiftDist;
+        return softfloat_roundPackToF16( sign, 0x1C - shiftDist, sig );
+    }
+
+}
+