/*      $NetBSD: divsi3.S,v 1.4 2003/04/05 23:27:15 bjh21 Exp $ */

/*
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <machine/asm.h>
/* 
 * stack is aligned as there's a possibility of branching to L_overflow
 * which makes a C call
 */

ENTRY(__umodsi3)
        stmfd   sp!, {lr}
        sub     sp, sp, #4      /* align stack */
        bl      .L_udivide
        add     sp, sp, #4      /* unalign stack */
        mov     r0, r1
        ldmfd   sp!, {pc}
END(__umodsi3)

ENTRY(__modsi3)
        stmfd   sp!, {lr}
        sub     sp, sp, #4      /* align stack */
        bl      .L_divide
        add     sp, sp, #4      /* unalign stack */
        mov     r0, r1
        ldmfd   sp!, {pc}

.L_overflow:
#if !defined(_KERNEL) && !defined(_STANDALONE)
        mov     r0, #8                  /* SIGFPE */
        bl      PIC_SYM(_C_LABEL(raise), PLT)   /* raise it */
        mov     r0, #0
#else
        /* XXX should cause a fatal error */
        mvn     r0, #0
#endif
        RET
END(__modsi3)

ENTRY(__udivsi3)
.L_udivide:                             /* r0 = r0 / r1; r1 = r0 % r1 */
        eor     r0, r1, r0 
        eor     r1, r0, r1 
        eor     r0, r1, r0 
                                        /* r0 = r1 / r0; r1 = r1 % r0 */
        cmp     r0, #1
        bcc     .L_overflow
        beq     .L_divide_l0
        mov     ip, #0
        movs    r1, r1
        bpl     .L_divide_l1
        orr     ip, ip, #0x20000000     /* ip bit 0x20000000 = -ve r1 */
        movs    r1, r1, lsr #1
        orrcs   ip, ip, #0x10000000     /* ip bit 0x10000000 = bit 0 of r1 */
        b       .L_divide_l1

.L_divide_l0:                           /* r0 == 1 */
        mov     r0, r1
        mov     r1, #0
        RET
END(__udivsi3)

ENTRY(__divsi3)
.L_divide:                              /* r0 = r0 / r1; r1 = r0 % r1 */
        eor     r0, r1, r0 
        eor     r1, r0, r1 
        eor     r0, r1, r0 
                                        /* r0 = r1 / r0; r1 = r1 % r0 */
        cmp     r0, #1
        bcc     .L_overflow
        beq     .L_divide_l0
        ands    ip, r0, #0x80000000
        rsbmi   r0, r0, #0
        ands    r2, r1, #0x80000000
        eor     ip, ip, r2
        rsbmi   r1, r1, #0
        orr     ip, r2, ip, lsr #1      /* ip bit 0x40000000 = -ve division */
                                        /* ip bit 0x80000000 = -ve remainder */

.L_divide_l1:
        mov     r2, #1
        mov     r3, #0

        /*
         * If the highest bit of the dividend is set, we have to be
         * careful when shifting the divisor. Test this. 
         */
        movs    r1,r1
        bpl     .L_old_code

        /*
         * At this point, the highest bit of r1 is known to be set.
         * We abuse this below in the tst instructions.
         */
        tst     r1, r0 /*, lsl #0 */
        bmi     .L_divide_b1
        tst     r1, r0, lsl #1
        bmi     .L_divide_b2
        tst     r1, r0, lsl #2
        bmi     .L_divide_b3
        tst     r1, r0, lsl #3
        bmi     .L_divide_b4
        tst     r1, r0, lsl #4
        bmi     .L_divide_b5
        tst     r1, r0, lsl #5
        bmi     .L_divide_b6
        tst     r1, r0, lsl #6
        bmi     .L_divide_b7
        tst     r1, r0, lsl #7
        bmi     .L_divide_b8
        tst     r1, r0, lsl #8
        bmi     .L_divide_b9
        tst     r1, r0, lsl #9
        bmi     .L_divide_b10
        tst     r1, r0, lsl #10
        bmi     .L_divide_b11
        tst     r1, r0, lsl #11
        bmi     .L_divide_b12
        tst     r1, r0, lsl #12
        bmi     .L_divide_b13
        tst     r1, r0, lsl #13
        bmi     .L_divide_b14
        tst     r1, r0, lsl #14
        bmi     .L_divide_b15
        tst     r1, r0, lsl #15
        bmi     .L_divide_b16
        tst     r1, r0, lsl #16
        bmi     .L_divide_b17
        tst     r1, r0, lsl #17
        bmi     .L_divide_b18
        tst     r1, r0, lsl #18
        bmi     .L_divide_b19
        tst     r1, r0, lsl #19
        bmi     .L_divide_b20
        tst     r1, r0, lsl #20
        bmi     .L_divide_b21
        tst     r1, r0, lsl #21
        bmi     .L_divide_b22
        tst     r1, r0, lsl #22
        bmi     .L_divide_b23
        tst     r1, r0, lsl #23
        bmi     .L_divide_b24
        tst     r1, r0, lsl #24
        bmi     .L_divide_b25
        tst     r1, r0, lsl #25
        bmi     .L_divide_b26
        tst     r1, r0, lsl #26
        bmi     .L_divide_b27
        tst     r1, r0, lsl #27
        bmi     .L_divide_b28
        tst     r1, r0, lsl #28
        bmi     .L_divide_b29
        tst     r1, r0, lsl #29
        bmi     .L_divide_b30
        tst     r1, r0, lsl #30
        bmi     .L_divide_b31
/*
 * instead of:
 *      tst     r1, r0, lsl #31
 *      bmi     .L_divide_b32
 */
        b       .L_divide_b32

.L_old_code:
        cmp     r1, r0
        bcc     .L_divide_b0
        cmp     r1, r0, lsl #1
        bcc     .L_divide_b1
        cmp     r1, r0, lsl #2
        bcc     .L_divide_b2
        cmp     r1, r0, lsl #3
        bcc     .L_divide_b3
        cmp     r1, r0, lsl #4
        bcc     .L_divide_b4
        cmp     r1, r0, lsl #5
        bcc     .L_divide_b5
        cmp     r1, r0, lsl #6
        bcc     .L_divide_b6
        cmp     r1, r0, lsl #7
        bcc     .L_divide_b7
        cmp     r1, r0, lsl #8
        bcc     .L_divide_b8
        cmp     r1, r0, lsl #9
        bcc     .L_divide_b9
        cmp     r1, r0, lsl #10
        bcc     .L_divide_b10
        cmp     r1, r0, lsl #11
        bcc     .L_divide_b11
        cmp     r1, r0, lsl #12
        bcc     .L_divide_b12
        cmp     r1, r0, lsl #13
        bcc     .L_divide_b13
        cmp     r1, r0, lsl #14
        bcc     .L_divide_b14
        cmp     r1, r0, lsl #15
        bcc     .L_divide_b15
        cmp     r1, r0, lsl #16
        bcc     .L_divide_b16
        cmp     r1, r0, lsl #17
        bcc     .L_divide_b17
        cmp     r1, r0, lsl #18
        bcc     .L_divide_b18
        cmp     r1, r0, lsl #19
        bcc     .L_divide_b19
        cmp     r1, r0, lsl #20
        bcc     .L_divide_b20
        cmp     r1, r0, lsl #21
        bcc     .L_divide_b21
        cmp     r1, r0, lsl #22
        bcc     .L_divide_b22
        cmp     r1, r0, lsl #23
        bcc     .L_divide_b23
        cmp     r1, r0, lsl #24
        bcc     .L_divide_b24
        cmp     r1, r0, lsl #25
        bcc     .L_divide_b25
        cmp     r1, r0, lsl #26
        bcc     .L_divide_b26
        cmp     r1, r0, lsl #27
        bcc     .L_divide_b27
        cmp     r1, r0, lsl #28
        bcc     .L_divide_b28
        cmp     r1, r0, lsl #29
        bcc     .L_divide_b29
        cmp     r1, r0, lsl #30
        bcc     .L_divide_b30
.L_divide_b32:
        cmp     r1, r0, lsl #31
        subhs   r1, r1,r0, lsl #31
        addhs   r3, r3,r2, lsl #31
.L_divide_b31:
        cmp     r1, r0, lsl #30
        subhs   r1, r1,r0, lsl #30
        addhs   r3, r3,r2, lsl #30
.L_divide_b30:
        cmp     r1, r0, lsl #29
        subhs   r1, r1,r0, lsl #29
        addhs   r3, r3,r2, lsl #29
.L_divide_b29:
        cmp     r1, r0, lsl #28
        subhs   r1, r1,r0, lsl #28
        addhs   r3, r3,r2, lsl #28
.L_divide_b28:
        cmp     r1, r0, lsl #27
        subhs   r1, r1,r0, lsl #27
        addhs   r3, r3,r2, lsl #27
.L_divide_b27:
        cmp     r1, r0, lsl #26
        subhs   r1, r1,r0, lsl #26
        addhs   r3, r3,r2, lsl #26
.L_divide_b26:
        cmp     r1, r0, lsl #25
        subhs   r1, r1,r0, lsl #25
        addhs   r3, r3,r2, lsl #25
.L_divide_b25:
        cmp     r1, r0, lsl #24
        subhs   r1, r1,r0, lsl #24
        addhs   r3, r3,r2, lsl #24
.L_divide_b24:
        cmp     r1, r0, lsl #23
        subhs   r1, r1,r0, lsl #23
        addhs   r3, r3,r2, lsl #23
.L_divide_b23:
        cmp     r1, r0, lsl #22
        subhs   r1, r1,r0, lsl #22
        addhs   r3, r3,r2, lsl #22
.L_divide_b22:
        cmp     r1, r0, lsl #21
        subhs   r1, r1,r0, lsl #21
        addhs   r3, r3,r2, lsl #21
.L_divide_b21:
        cmp     r1, r0, lsl #20
        subhs   r1, r1,r0, lsl #20
        addhs   r3, r3,r2, lsl #20
.L_divide_b20:
        cmp     r1, r0, lsl #19
        subhs   r1, r1,r0, lsl #19
        addhs   r3, r3,r2, lsl #19
.L_divide_b19:
        cmp     r1, r0, lsl #18
        subhs   r1, r1,r0, lsl #18
        addhs   r3, r3,r2, lsl #18
.L_divide_b18:
        cmp     r1, r0, lsl #17
        subhs   r1, r1,r0, lsl #17
        addhs   r3, r3,r2, lsl #17
.L_divide_b17:
        cmp     r1, r0, lsl #16
        subhs   r1, r1,r0, lsl #16
        addhs   r3, r3,r2, lsl #16
.L_divide_b16:
        cmp     r1, r0, lsl #15
        subhs   r1, r1,r0, lsl #15
        addhs   r3, r3,r2, lsl #15
.L_divide_b15:
        cmp     r1, r0, lsl #14
        subhs   r1, r1,r0, lsl #14
        addhs   r3, r3,r2, lsl #14
.L_divide_b14:
        cmp     r1, r0, lsl #13
        subhs   r1, r1,r0, lsl #13
        addhs   r3, r3,r2, lsl #13
.L_divide_b13:
        cmp     r1, r0, lsl #12
        subhs   r1, r1,r0, lsl #12
        addhs   r3, r3,r2, lsl #12
.L_divide_b12:
        cmp     r1, r0, lsl #11
        subhs   r1, r1,r0, lsl #11
        addhs   r3, r3,r2, lsl #11
.L_divide_b11:
        cmp     r1, r0, lsl #10
        subhs   r1, r1,r0, lsl #10
        addhs   r3, r3,r2, lsl #10
.L_divide_b10:
        cmp     r1, r0, lsl #9
        subhs   r1, r1,r0, lsl #9
        addhs   r3, r3,r2, lsl #9
.L_divide_b9:
        cmp     r1, r0, lsl #8
        subhs   r1, r1,r0, lsl #8
        addhs   r3, r3,r2, lsl #8
.L_divide_b8:
        cmp     r1, r0, lsl #7
        subhs   r1, r1,r0, lsl #7
        addhs   r3, r3,r2, lsl #7
.L_divide_b7:
        cmp     r1, r0, lsl #6
        subhs   r1, r1,r0, lsl #6
        addhs   r3, r3,r2, lsl #6
.L_divide_b6:
        cmp     r1, r0, lsl #5
        subhs   r1, r1,r0, lsl #5
        addhs   r3, r3,r2, lsl #5
.L_divide_b5:
        cmp     r1, r0, lsl #4
        subhs   r1, r1,r0, lsl #4
        addhs   r3, r3,r2, lsl #4
.L_divide_b4:
        cmp     r1, r0, lsl #3
        subhs   r1, r1,r0, lsl #3
        addhs   r3, r3,r2, lsl #3
.L_divide_b3:
        cmp     r1, r0, lsl #2
        subhs   r1, r1,r0, lsl #2
        addhs   r3, r3,r2, lsl #2
.L_divide_b2:
        cmp     r1, r0, lsl #1
        subhs   r1, r1,r0, lsl #1
        addhs   r3, r3,r2, lsl #1
.L_divide_b1:
        cmp     r1, r0
        subhs   r1, r1, r0
        addhs   r3, r3, r2
.L_divide_b0:

        tst     ip, #0x20000000
        bne     .L_udivide_l1
        mov     r0, r3
        cmp     ip, #0
        rsbmi   r1, r1, #0
        movs    ip, ip, lsl #1
        bicmi   r0, r0, #0x80000000     /* Fix incase we divided 0x80000000 */
        rsbmi   r0, r0, #0
        RET

.L_udivide_l1:
        tst     ip, #0x10000000
        mov     r1, r1, lsl #1
        orrne   r1, r1, #1
        mov     r3, r3, lsl #1
        cmp     r1, r0
        subhs   r1, r1, r0
        addhs   r3, r3, r2
        mov     r0, r3
        RET
END(__divsi3)

        .section .note.GNU-stack,"",%progbits