cplxabs.asm

来自「开放源码的编译器open watcom 1.6.0版的源代码」· 汇编 代码 · 共 68 行

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;
; CPLXABS       : complex absolute value
;

.8087

include struct.inc
include mdef.inc

        modstart        cplxabs


        xdefp   IF@CABS
defp    IF@CABS
endproc IF@CABS


        xdefp   IF@CDABS
defp    IF@CDABS
endproc IF@CDABS


; Compute absolute value of a complex number

defp    CplxAbs
        fmul    st(0),st(0)             ; compute a*a
        fxch    st(1)                   ; compute b*b
        fmul    st(0),st(0)             ; ...
        faddp   st(1),st(0)             ; compute a*a + b*b
        fsqrt                           ; complete absolute value
        ret
endproc CplxAbs

        endmod
        end