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Diffstat (limited to 'arch/sparc/lib/udiv.S')
| -rw-r--r-- | arch/sparc/lib/udiv.S | 357 | 
1 files changed, 0 insertions, 357 deletions
diff --git a/arch/sparc/lib/udiv.S b/arch/sparc/lib/udiv.S deleted file mode 100644 index 2101405bdfc..00000000000 --- a/arch/sparc/lib/udiv.S +++ /dev/null @@ -1,357 +0,0 @@ -/* - * udiv.S:      This routine was taken from glibc-1.09 and is covered - *              by the GNU Library General Public License Version 2. - */ - - -/* This file is generated from divrem.m4; DO NOT EDIT! */ -/* - * Division and remainder, from Appendix E of the Sparc Version 8 - * Architecture Manual, with fixes from Gordon Irlam. - */ - -/* - * Input: dividend and divisor in %o0 and %o1 respectively. - * - * m4 parameters: - *  .udiv	name of function to generate - *  div		div=div => %o0 / %o1; div=rem => %o0 % %o1 - *  false		false=true => signed; false=false => unsigned - * - * Algorithm parameters: - *  N		how many bits per iteration we try to get (4) - *  WORDSIZE	total number of bits (32) - * - * Derived constants: - *  TOPBITS	number of bits in the top decade of a number - * - * Important variables: - *  Q		the partial quotient under development (initially 0) - *  R		the remainder so far, initially the dividend - *  ITER	number of main division loop iterations required; - *		equal to ceil(log2(quotient) / N).  Note that this - *		is the log base (2^N) of the quotient. - *  V		the current comparand, initially divisor*2^(ITER*N-1) - * - * Cost: - *  Current estimate for non-large dividend is - *	ceil(log2(quotient) / N) * (10 + 7N/2) + C - *  A large dividend is one greater than 2^(31-TOPBITS) and takes a - *  different path, as the upper bits of the quotient must be developed - *  one bit at a time. - */ - - -	.globl .udiv -	.globl _Udiv -.udiv: -_Udiv:	/* needed for export */ - -	! Ready to divide.  Compute size of quotient; scale comparand. -	orcc	%o1, %g0, %o5 -	bne	1f -	 mov	%o0, %o3 - -		! Divide by zero trap.  If it returns, return 0 (about as -		! wrong as possible, but that is what SunOS does...). -		ta	ST_DIV0 -		retl -		 clr	%o0 - -1: -	cmp	%o3, %o5			! if %o1 exceeds %o0, done -	blu	Lgot_result		! (and algorithm fails otherwise) -	 clr	%o2 - -	sethi	%hi(1 << (32 - 4 - 1)), %g1 - -	cmp	%o3, %g1 -	blu	Lnot_really_big -	 clr	%o4 - -	! Here the dividend is >= 2**(31-N) or so.  We must be careful here, -	! as our usual N-at-a-shot divide step will cause overflow and havoc. -	! The number of bits in the result here is N*ITER+SC, where SC <= N. -	! Compute ITER in an unorthodox manner: know we need to shift V into -	! the top decade: so do not even bother to compare to R. -	1: -		cmp	%o5, %g1 -		bgeu	3f -		 mov	1, %g7 - -		sll	%o5, 4, %o5 - -		b	1b -		 add	%o4, 1, %o4 - -	! Now compute %g7. -	2: -		addcc	%o5, %o5, %o5 -		bcc	Lnot_too_big -		 add	%g7, 1, %g7 - -		! We get here if the %o1 overflowed while shifting. -		! This means that %o3 has the high-order bit set. -		! Restore %o5 and subtract from %o3. -		sll	%g1, 4, %g1	! high order bit -		srl	%o5, 1, %o5		! rest of %o5 -		add	%o5, %g1, %o5 - -		b	Ldo_single_div -		 sub	%g7, 1, %g7 - -	Lnot_too_big: -	3: -		cmp	%o5, %o3 -		blu	2b -		 nop - -		be	Ldo_single_div -		 nop -	/* NB: these are commented out in the V8-Sparc manual as well */ -	/* (I do not understand this) */ -	! %o5 > %o3: went too far: back up 1 step -	!	srl	%o5, 1, %o5 -	!	dec	%g7 -	! do single-bit divide steps -	! -	! We have to be careful here.  We know that %o3 >= %o5, so we can do the -	! first divide step without thinking.  BUT, the others are conditional, -	! and are only done if %o3 >= 0.  Because both %o3 and %o5 may have the high- -	! order bit set in the first step, just falling into the regular -	! division loop will mess up the first time around. -	! So we unroll slightly... -	Ldo_single_div: -		subcc	%g7, 1, %g7 -		bl	Lend_regular_divide -		 nop - -		sub	%o3, %o5, %o3 -		mov	1, %o2 - -		b	Lend_single_divloop -		 nop -	Lsingle_divloop: -		sll	%o2, 1, %o2 -		bl	1f -		 srl	%o5, 1, %o5 -		! %o3 >= 0 -		sub	%o3, %o5, %o3 -		b	2f -		 add	%o2, 1, %o2 -	1:	! %o3 < 0 -		add	%o3, %o5, %o3 -		sub	%o2, 1, %o2 -	2: -	Lend_single_divloop: -		subcc	%g7, 1, %g7 -		bge	Lsingle_divloop -		 tst	%o3 - -		b,a	Lend_regular_divide - -Lnot_really_big: -1: -	sll	%o5, 4, %o5 - -	cmp	%o5, %o3 -	bleu	1b -	 addcc	%o4, 1, %o4 - -	be	Lgot_result -	 sub	%o4, 1, %o4 - -	tst	%o3	! set up for initial iteration -Ldivloop: -	sll	%o2, 4, %o2 -		! depth 1, accumulated bits 0 -	bl	L.1.16 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 2, accumulated bits 1 -	bl	L.2.17 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 3, accumulated bits 3 -	bl	L.3.19 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 4, accumulated bits 7 -	bl	L.4.23 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (7*2+1), %o2 - -L.4.23: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (7*2-1), %o2 - -L.3.19: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 4, accumulated bits 5 -	bl	L.4.21 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (5*2+1), %o2 - -L.4.21: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (5*2-1), %o2 - -L.2.17: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 3, accumulated bits 1 -	bl	L.3.17 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 4, accumulated bits 3 -	bl	L.4.19 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (3*2+1), %o2 - -L.4.19: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (3*2-1), %o2 - -L.3.17: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 4, accumulated bits 1 -	bl	L.4.17 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (1*2+1), %o2 - -L.4.17: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (1*2-1), %o2 - -L.1.16: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 2, accumulated bits -1 -	bl	L.2.15 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 3, accumulated bits -1 -	bl	L.3.15 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 4, accumulated bits -1 -	bl	L.4.15 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-1*2+1), %o2 - -L.4.15: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-1*2-1), %o2 - -L.3.15: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 4, accumulated bits -3 -	bl	L.4.13 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-3*2+1), %o2 - -L.4.13: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-3*2-1), %o2 - -L.2.15: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 3, accumulated bits -3 -	bl	L.3.13 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -			! depth 4, accumulated bits -5 -	bl	L.4.11 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-5*2+1), %o2 - -L.4.11: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-5*2-1), %o2 - -L.3.13: -	! remainder is negative -	addcc	%o3,%o5,%o3 -			! depth 4, accumulated bits -7 -	bl	L.4.9 -	 srl	%o5,1,%o5 -	! remainder is positive -	subcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-7*2+1), %o2 - -L.4.9: -	! remainder is negative -	addcc	%o3,%o5,%o3 -	b	9f -	 add	%o2, (-7*2-1), %o2 - -	9: -Lend_regular_divide: -	subcc	%o4, 1, %o4 -	bge	Ldivloop -	 tst	%o3 - -	bl,a	Lgot_result -	! non-restoring fixup here (one instruction only!) -	sub	%o2, 1, %o2 - -Lgot_result: - -	retl -	 mov %o2, %o0 - -	.globl	.udiv_patch -.udiv_patch: -	wr	%g0, 0x0, %y -	nop -	nop -	retl -	 udiv	%o0, %o1, %o0 -	nop  |