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Diffstat (limited to 'softfloat/bf16_mulAdd.c')
| -rw-r--r-- | softfloat/bf16_mulAdd.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/softfloat/bf16_mulAdd.c b/softfloat/bf16_mulAdd.c new file mode 100644 index 0000000..5e67396 --- /dev/null +++ b/softfloat/bf16_mulAdd.c @@ -0,0 +1,67 @@ + +/*============================================================================ + +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 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 <stdint.h> +#include "platform.h" +#include "internals.h" +#include "softfloat.h" + +bfloat16_t bf16_mulAdd( bfloat16_t a, bfloat16_t b, bfloat16_t c ) +{ + uint_fast8_t roundingMode = softfloat_roundingMode; + + float64_t f64A = bf16_to_f64( a ); + float64_t f64B = bf16_to_f64( b ); + float64_t f64C = bf16_to_f64( c ); + + float64_t prod = f64_mul( f64A, f64B ); + + softfloat_roundingMode = softfloat_round_odd; + + float64_t sum = f64_add( prod, f64C ); + + softfloat_roundingMode = roundingMode; + + /* When rounding down, return -0 instead of +0 when product's sign + * differs from C's sign. */ + if ( softfloat_roundingMode == softfloat_round_min + && sum.v == 0 + && ( ( prod.v ^ f64C.v ) & 0x8000000000000000U ) != 0 ) + return (bfloat16_t) { 0x8000 }; + + return f64_to_bf16( sum ); +} + |