[people/ms/u-boot.git] / arch / arm / lib / _udivsi3.S

/* # 1 "libgcc1.S" */
@ libgcc1 routines for ARM cpu.
@ Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
dividend	.req	r0
divisor		.req	r1
result		.req	r2
curbit		.req	r3
/* ip		.req	r12	*/
/* sp		.req	r13	*/
/* lr		.req	r14	*/
/* pc		.req	r15	*/
	.text
	.globl	 __udivsi3
	.type	__udivsi3 ,function
	.globl	__aeabi_uidiv
	.type	__aeabi_uidiv ,function
	.align	0
 __udivsi3:
 __aeabi_uidiv:
	cmp	divisor, #0
	beq	Ldiv0
	mov	curbit, #1
	mov	result, #0
	cmp	dividend, divisor
	bcc	Lgot_result
Loop1:
	@ Unless the divisor is very big, shift it up in multiples of
	@ four bits, since this is the amount of unwinding in the main
	@ division loop.  Continue shifting until the divisor is
	@ larger than the dividend.
	cmp	divisor, #0x10000000
	cmpcc	divisor, dividend
	movcc	divisor, divisor, lsl #4
	movcc	curbit, curbit, lsl #4
	bcc	Loop1
Lbignum:
	@ For very big divisors, we must shift it a bit at a time, or
	@ we will be in danger of overflowing.
	cmp	divisor, #0x80000000
	cmpcc	divisor, dividend
	movcc	divisor, divisor, lsl #1
	movcc	curbit, curbit, lsl #1
	bcc	Lbignum
Loop3:
	@ Test for possible subtractions, and note which bits
	@ are done in the result.  On the final pass, this may subtract
	@ too much from the dividend, but the result will be ok, since the
	@ "bit" will have been shifted out at the bottom.
	cmp	dividend, divisor
	subcs	dividend, dividend, divisor
	orrcs	result, result, curbit
	cmp	dividend, divisor, lsr #1
	subcs	dividend, dividend, divisor, lsr #1
	orrcs	result, result, curbit, lsr #1
	cmp	dividend, divisor, lsr #2
	subcs	dividend, dividend, divisor, lsr #2
	orrcs	result, result, curbit, lsr #2
	cmp	dividend, divisor, lsr #3
	subcs	dividend, dividend, divisor, lsr #3
	orrcs	result, result, curbit, lsr #3
	cmp	dividend, #0			@ Early termination?
	movnes	curbit, curbit, lsr #4		@ No, any more bits to do?
	movne	divisor, divisor, lsr #4
	bne	Loop3
Lgot_result:
	mov	r0, result
	mov	pc, lr
Ldiv0:
	str	lr, [sp, #-4]!
	bl	 __div0       (PLT)
	mov	r0, #0			@ about as wrong as it could be
	ldmia	sp!, {pc}
	.size  __udivsi3       , . -  __udivsi3

.globl __aeabi_uidivmod
__aeabi_uidivmod:

	stmfd	sp!, {r0, r1, ip, lr}
	bl	__aeabi_uidiv
	ldmfd	sp!, {r1, r2, ip, lr}
	mul	r3, r0, r2
	sub	r1, r1, r3
	mov	pc, lr

.globl __aeabi_idivmod
__aeabi_idivmod:

	stmfd	sp!, {r0, r1, ip, lr}
	bl	__aeabi_idiv
	ldmfd	sp!, {r1, r2, ip, lr}
	mul	r3, r0, r2
	sub	r1, r1, r3
	mov	pc, lr
Commit	Line	Data
c609719b WD	1	/* # 1 "libgcc1.S" */
	2	@ libgcc1 routines for ARM cpu.
	3	@ Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
	4	dividend .req r0
	5	divisor .req r1
	6	result .req r2
	7	curbit .req r3
ac6dbb85 WD	8	/* ip .req r12 */
	9	/* sp .req r13 */
	10	/* lr .req r14 */
	11	/* pc .req r15 */
c609719b WD	12	.text
c609719b WD	13	.globl __udivsi3
59b4d747 WD	14	.type __udivsi3 ,function
	15	.globl __aeabi_uidiv
	16	.type __aeabi_uidiv ,function
c609719b	17	.align 0
59b4d747 WD	18	__udivsi3:
59b4d747 WD	19	__aeabi_uidiv:
c609719b WD	20	cmp divisor, #0
	21	beq Ldiv0
	22	mov curbit, #1
	23	mov result, #0
	24	cmp dividend, divisor
	25	bcc Lgot_result
	26	Loop1:
	27	@ Unless the divisor is very big, shift it up in multiples of
	28	@ four bits, since this is the amount of unwinding in the main
	29	@ division loop. Continue shifting until the divisor is
	30	@ larger than the dividend.
	31	cmp divisor, #0x10000000
	32	cmpcc divisor, dividend
	33	movcc divisor, divisor, lsl #4
	34	movcc curbit, curbit, lsl #4
	35	bcc Loop1
	36	Lbignum:
	37	@ For very big divisors, we must shift it a bit at a time, or
	38	@ we will be in danger of overflowing.
	39	cmp divisor, #0x80000000
	40	cmpcc divisor, dividend
	41	movcc divisor, divisor, lsl #1
	42	movcc curbit, curbit, lsl #1
	43	bcc Lbignum
	44	Loop3:
	45	@ Test for possible subtractions, and note which bits
	46	@ are done in the result. On the final pass, this may subtract
	47	@ too much from the dividend, but the result will be ok, since the
	48	@ "bit" will have been shifted out at the bottom.
	49	cmp dividend, divisor
	50	subcs dividend, dividend, divisor
	51	orrcs result, result, curbit
	52	cmp dividend, divisor, lsr #1
	53	subcs dividend, dividend, divisor, lsr #1
	54	orrcs result, result, curbit, lsr #1
	55	cmp dividend, divisor, lsr #2
	56	subcs dividend, dividend, divisor, lsr #2
	57	orrcs result, result, curbit, lsr #2
	58	cmp dividend, divisor, lsr #3
	59	subcs dividend, dividend, divisor, lsr #3
	60	orrcs result, result, curbit, lsr #3
	61	cmp dividend, #0 @ Early termination?
	62	movnes curbit, curbit, lsr #4 @ No, any more bits to do?
	63	movne divisor, divisor, lsr #4
	64	bne Loop3
	65	Lgot_result:
	66	mov r0, result
53677ef1	67	mov pc, lr
c609719b WD	68	Ldiv0:
	69	str lr, [sp, #-4]!
	70	bl __div0 (PLT)
	71	mov r0, #0 @ about as wrong as it could be
	72	ldmia sp!, {pc}
	73	.size __udivsi3 , . - __udivsi3
59b4d747 WD	74
	75	.globl __aeabi_uidivmod
	76	__aeabi_uidivmod:
	77
	78	stmfd sp!, {r0, r1, ip, lr}
	79	bl __aeabi_uidiv
	80	ldmfd sp!, {r1, r2, ip, lr}
	81	mul r3, r0, r2
	82	sub r1, r1, r3
	83	mov pc, lr
	84
	85	.globl __aeabi_idivmod
	86	__aeabi_idivmod:
	87
	88	stmfd sp!, {r0, r1, ip, lr}
	89	bl __aeabi_idiv
	90	ldmfd sp!, {r1, r2, ip, lr}
	91	mul r3, r0, r2
	92	sub r1, r1, r3
	93	mov pc, lr