usr/src/sys/tahoe/math/Ksubf.s

/*      Ksubf.s 1.2     86/01/03        */

#include "SYS.h"

/*
 * _Ksubf(acc_most,acc_least,op_most,op_least,hfs)
 *
 * subf(d1,d2)
 * {
 *      return(d1+(-d2));
 * }
 */
        .text
ENTRY(Ksubf, 0)
        tstl    4(fp)   # handle (a-b) where a and/or b = 0.0
        jneq    next
        movl    $0,r1
        movl    12(fp),r0
        lnd     r0
        std     r0
        ret
next:
        tstl    12(fp)
        jneq    doit
        movl    $0,r1
        movl    4(fp),r0
        ret
doit:
        lnd     12(fp)  # note: -(0) = 0 by definition!
        pushl   20(fp)  # hfs
        pushd
        pushl   8(fp)
        pushl   4(fp)   # acc
        callf   $24,_Kaddf
        ret