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FPREM1       Partial IEEE Remainder (80387)         Exception Flags: I D U

FPREM1

       Logic:      ST . remainder (ST / ST(1))

     FPREM1 calculates the remainder of ST divided by ST(1). It generates
     the IEEE-754 standard partial remainder answer. This may differ from
     PREM when two integers are equally close to the answer; FPREM rounds
     towards 0 and FPREM1 always chooses the even value.

     FPREM1 also indicates the least-significant three bits of the
     quotient generated by FPREM in C3 C1 and C0 as follows:

                C3 C2 C1 C0 Meaning
                -- -- -- -- -------
                ?  1  ?  ?  Incomplete reduction
                0  0  0  0  quotient MOD 8 = 0
                0  0  0  1  quotient MOD 8 = 4
                0  0  1  0  quotient MOD 8 = 1
                0  0  1  1  quotient MOD 8 = 5
                1  0  0  0  quotient MOD 8 = 2
                1  0  0  1  quotient MOD 8 = 6
                1  0  1  0  quotient MOD 8 = 3
                1  0  1  1  quotient MOD 8 = 7

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   Operands            Clocks         Bytes           Example
   FPREM1              95-185 (387)     3             FPREM1
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