fabs387.asm

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;*                            Open Watcom Project
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;*  ========================================================================
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;*    This file contains Original Code and/or Modifications of Original
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ifdef __386__
 .387
else
 .8087
endif
include mdef.inc
include math387.inc

        xref     __8087  ; indicate that NDP instructions are present
        modstart fabs387

        xdefp    "C",fabs       ; double fabs( double x )

ifndef __386__
if _MODEL and _BIG_CODE
argx    equ     6
else
argx    equ     4
endif
endif

;  input:       x - on the stack
;  output:      absolute value of x in st(0)
;
        defp    fabs
ifdef __386__
        and     byte ptr 4+7[ESP],7Fh   ; turn off sign bit
ifdef __STACK__
        mov     EAX,4[ESP]              ; load value
        mov     EDX,8[ESP]              ; ...
else
        fld     qword ptr 4[ESP]        ; load value
        fwait                           ; wait
endif
else
        push    BP                      ; save BP
        mov     BP,SP                   ; get access to stack
        fld     qword ptr argx[BP]      ; load argument
        fabs                            ; take absolute value
        pop     BP                      ; restore BP
endif
        ret_pop 8                       ; return
        endproc fabs

        public  IF@DABS
        public  IF@ABS
        defp    IF@DABS
        defp    IF@ABS
        fabs                            ; calculate absolute value of argument
        ret                             ; return
        endproc IF@ABS
        endproc IF@DABS

        endmod
        end