diff options
Diffstat (limited to 'sys/libkern/arm/divsi3.S')
| -rw-r--r-- | sys/libkern/arm/divsi3.S | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/sys/libkern/arm/divsi3.S b/sys/libkern/arm/divsi3.S new file mode 100644 index 0000000..baab96b --- /dev/null +++ b/sys/libkern/arm/divsi3.S @@ -0,0 +1,387 @@ +/* $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> +__FBSDID("$FreeBSD$"); + +/* + * 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} + +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 + mov pc, lr + +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 + mov pc, lr + +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 + mov pc, lr + +.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 + mov pc, lr |
