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4349 Serge 1
/*
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FUNCTION
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<>, <>--floating multiply add
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INDEX
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	fma
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INDEX
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	fmaf
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ANSI_SYNOPSIS
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	#include 
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	double fma(double <[x]>, double <[y]>, double <[z]>);
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	float fmaf(float <[x]>, float <[y]>, float <[z]>);
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DESCRIPTION
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The <> functions compute (<[x]> * <[y]>) + <[z]>, rounded as one ternary
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operation:  they compute the value (as if) to infinite precision and round once
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to the result format, according to the rounding mode characterized by the value
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of FLT_ROUNDS.  That is, they are supposed to do this:  see below.
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RETURNS
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The <> functions return (<[x]> * <[y]>) + <[z]>, rounded as one ternary
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operation.
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BUGS
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This implementation does not provide the function that it should, purely
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returning "(<[x]> * <[y]>) + <[z]>;" with no attempt at all to provide the
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simulated infinite precision intermediates which are required.  DO NOT USE THEM.
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If double has enough more precision than float, then <> should provide
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the expected numeric results, as it does use double for the calculation.  But
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since this is not the case for all platforms, this manual cannot determine
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if it is so for your case.
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PORTABILITY
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ANSI C, POSIX.
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*/
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#include "fdlibm.h"
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#ifndef _DOUBLE_IS_32BITS
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#ifdef __STDC__
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	double fma(double x, double y, double z)
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#else
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	double fma(x,y)
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	double x;
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	double y;
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        double z;
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#endif
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{
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  /* Implementation defined. */
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  return (x * y) + z;
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}
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#endif /* _DOUBLE_IS_32BITS */