/*
     * Generic 32-bit floating-point operation.  Provide an "instr" line that
     * specifies an instruction that performs "s2 = s0 op s1".  Because we
     * use the "softfp" ABI, this must be an instruction, not a function call.
     *
     * For: add-float, sub-float, mul-float, div-float
     */
    /* floatop vAA, vBB, vCC */
    FETCH r0, 1                         @ r0<- CCBB
    mov     r9, rINST, lsr #8           @ r9<- AA
    mov     r3, r0, lsr #8              @ r3<- CC
    and     r2, r0, #255                @ r2<- BB
    VREG_INDEX_TO_ADDR r3, r3           @ r3<- &vCC
    VREG_INDEX_TO_ADDR r2, r2           @ r2<- &vBB
    flds    s1, [r3]                    @ s1<- vCC
    flds    s0, [r2]                    @ s0<- vBB

    FETCH_ADVANCE_INST 2                @ advance rPC, load rINST
    $instr                              @ s2<- op
    GET_INST_OPCODE ip                  @ extract opcode from rINST
    VREG_INDEX_TO_ADDR r9, r9           @ r9<- &vAA
    fsts    s2, [r9]                    @ vAA<- s2
    GOTO_OPCODE ip                      @ jump to next instruction