[thirdparty/glibc.git] / sysdeps / m68k / m680x0 / lshift.S

/* mc68020 __mpn_lshift -- Shift left a low-level natural-number integer.

Copyright (C) 1996-2019 Free Software Foundation, Inc.

This file is part of the GNU MP Library.

The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version.

The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library.  If not, see <https://www.gnu.org/licenses/>.  */

/*
  INPUT PARAMETERS
  res_ptr	(sp + 4)
  s_ptr		(sp + 8)
  s_size	(sp + 16)
  cnt		(sp + 12)
*/

#include "sysdep.h"
#include "asm-syntax.h"

#define res_ptr a1
#define s_ptr a0
#define s_size d6
#define cnt d4

	TEXT
ENTRY(__mpn_lshift)

/* Save used registers on the stack.  */
	moveml	R(d2)-R(d6)/R(a2),MEM_PREDEC(sp)
	cfi_adjust_cfa_offset (6*4)
	cfi_rel_offset (R(d2), 0)
	cfi_rel_offset (R(d3), 4)
	cfi_rel_offset (R(d4), 8)
	cfi_rel_offset (R(d5), 12)
	cfi_rel_offset (R(d6), 16)
	cfi_rel_offset (R(a2), 20)

/* Copy the arguments to registers.  */
	movel	MEM_DISP(sp,28),R(res_ptr)
	movel	MEM_DISP(sp,32),R(s_ptr)
	movel	MEM_DISP(sp,36),R(s_size)
	movel	MEM_DISP(sp,40),R(cnt)

	moveql	#1,R(d5)
	cmpl	R(d5),R(cnt)
	bne	L(Lnormal)
	cmpl	R(s_ptr),R(res_ptr)
	bls	L(Lspecial)		/* jump if s_ptr >= res_ptr */
#if (defined (__mc68020__) || defined (__NeXT__) || defined(mc68020))
	lea	MEM_INDX1(s_ptr,s_size,l,4),R(a2)
#else /* not mc68020 */
	movel	R(s_size),R(d0)
	asll	#2,R(d0)
	lea	MEM_INDX(s_ptr,d0,l),R(a2)
#endif
	cmpl	R(res_ptr),R(a2)
	bls	L(Lspecial)		/* jump if res_ptr >= s_ptr + s_size */

L(Lnormal:)
	moveql	#32,R(d5)
	subl	R(cnt),R(d5)

#if (defined (__mc68020__) || defined (__NeXT__) || defined(mc68020))
	lea	MEM_INDX1(s_ptr,s_size,l,4),R(s_ptr)
	lea	MEM_INDX1(res_ptr,s_size,l,4),R(res_ptr)
#else /* not mc68000 */
	movel	R(s_size),R(d0)
	asll	#2,R(d0)
	addl	R(s_size),R(s_ptr)
	addl	R(s_size),R(res_ptr)
#endif
	movel	MEM_PREDEC(s_ptr),R(d2)
	movel	R(d2),R(d0)
	lsrl	R(d5),R(d0)		/* compute carry limb */

	lsll	R(cnt),R(d2)
	movel	R(d2),R(d1)
	subql	#1,R(s_size)
	beq	L(Lend)
	lsrl	#1,R(s_size)
	bcs	L(L1)
	subql	#1,R(s_size)

L(Loop:)
	movel	MEM_PREDEC(s_ptr),R(d2)
	movel	R(d2),R(d3)
	lsrl	R(d5),R(d3)
	orl	R(d3),R(d1)
	movel	R(d1),MEM_PREDEC(res_ptr)
	lsll	R(cnt),R(d2)
L(L1:)
	movel	MEM_PREDEC(s_ptr),R(d1)
	movel	R(d1),R(d3)
	lsrl	R(d5),R(d3)
	orl	R(d3),R(d2)
	movel	R(d2),MEM_PREDEC(res_ptr)
	lsll	R(cnt),R(d1)

	dbf	R(s_size),L(Loop)
	subl	#0x10000,R(s_size)
	bcc	L(Loop)

L(Lend:)
	movel	R(d1),MEM_PREDEC(res_ptr) /* store least significant limb */

/* Restore used registers from stack frame.  */
	moveml	MEM_POSTINC(sp),R(d2)-R(d6)/R(a2)
	cfi_remember_state
	cfi_adjust_cfa_offset (-6*4)
	cfi_restore (R(d2))
	cfi_restore (R(d3))
	cfi_restore (R(d4))
	cfi_restore (R(d5))
	cfi_restore (R(d6))
	cfi_restore (R(a2))
	rts

/* We loop from least significant end of the arrays, which is only
   permissible if the source and destination don't overlap, since the
   function is documented to work for overlapping source and destination.  */

	cfi_restore_state
L(Lspecial:)
	clrl	R(d0)			/* initialize carry */
	eorw	#1,R(s_size)
	lsrl	#1,R(s_size)
	bcc	L(LL1)
	subql	#1,R(s_size)

L(LLoop:)
	movel	MEM_POSTINC(s_ptr),R(d2)
	addxl	R(d2),R(d2)
	movel	R(d2),MEM_POSTINC(res_ptr)
L(LL1:)
	movel	MEM_POSTINC(s_ptr),R(d2)
	addxl	R(d2),R(d2)
	movel	R(d2),MEM_POSTINC(res_ptr)

	dbf	R(s_size),L(LLoop)
	addxl	R(d0),R(d0)		/* save cy in lsb */
	subl	#0x10000,R(s_size)
	bcs	L(LLend)
	lsrl	#1,R(d0)		/* restore cy */
	bra	L(LLoop)

L(LLend:)
/* Restore used registers from stack frame.  */
	moveml	MEM_POSTINC(sp),R(d2)-R(d6)/R(a2)
	cfi_adjust_cfa_offset (-6*4)
	cfi_restore (R(d2))
	cfi_restore (R(d3))
	cfi_restore (R(d4))
	cfi_restore (R(d5))
	cfi_restore (R(d6))
	cfi_restore (R(a2))
	rts
END(__mpn_lshift)
Commit	Line	Data
3de9f02e RM	1	/* mc68020 __mpn_lshift -- Shift left a low-level natural-number integer.
3de9f02e RM	2
04277e02	3	Copyright (C) 1996-2019 Free Software Foundation, Inc.
3de9f02e RM	4
	5	This file is part of the GNU MP Library.
	6
	7	The GNU MP Library is free software; you can redistribute it and/or modify
f01ec467 AJ	8	it under the terms of the GNU Lesser General Public License as published by
f01ec467 AJ	9	the Free Software Foundation; either version 2.1 of the License, or (at your
3de9f02e RM	10	option) any later version.
	11
	12	The GNU MP Library is distributed in the hope that it will be useful, but
	13	WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
f01ec467	14	or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
3de9f02e RM	15	License for more details.
3de9f02e RM	16
f01ec467	17	You should have received a copy of the GNU Lesser General Public License
5a82c748	18	along with the GNU MP Library. If not, see <https://www.gnu.org/licenses/>. */
3de9f02e RM	19
	20	/*
	21	INPUT PARAMETERS
	22	res_ptr (sp + 4)
	23	s_ptr (sp + 8)
	24	s_size (sp + 16)
	25	cnt (sp + 12)
	26	*/
	27
	28	#include "sysdep.h"
	29	#include "asm-syntax.h"
	30
	31	#define res_ptr a1
	32	#define s_ptr a0
	33	#define s_size d6
	34	#define cnt d4
	35
	36	TEXT
56d7f029	37	ENTRY(__mpn_lshift)
3de9f02e RM	38
	39	/* Save used registers on the stack. */
	40	moveml R(d2)-R(d6)/R(a2),MEM_PREDEC(sp)
50e73d13 AS	41	cfi_adjust_cfa_offset (6*4)
	42	cfi_rel_offset (R(d2), 0)
	43	cfi_rel_offset (R(d3), 4)
	44	cfi_rel_offset (R(d4), 8)
	45	cfi_rel_offset (R(d5), 12)
	46	cfi_rel_offset (R(d6), 16)
	47	cfi_rel_offset (R(a2), 20)
3de9f02e RM	48
	49	/* Copy the arguments to registers. */
	50	movel MEM_DISP(sp,28),R(res_ptr)
	51	movel MEM_DISP(sp,32),R(s_ptr)
	52	movel MEM_DISP(sp,36),R(s_size)
	53	movel MEM_DISP(sp,40),R(cnt)
	54
	55	moveql #1,R(d5)
	56	cmpl R(d5),R(cnt)
	57	bne L(Lnormal)
	58	cmpl R(s_ptr),R(res_ptr)
	59	bls L(Lspecial) /* jump if s_ptr >= res_ptr */
	60	#if (defined (__mc68020__) \|\| defined (__NeXT__) \|\| defined(mc68020))
	61	lea MEM_INDX1(s_ptr,s_size,l,4),R(a2)
	62	#else /* not mc68020 */
	63	movel R(s_size),R(d0)
	64	asll #2,R(d0)
	65	lea MEM_INDX(s_ptr,d0,l),R(a2)
	66	#endif
	67	cmpl R(res_ptr),R(a2)
	68	bls L(Lspecial) /* jump if res_ptr >= s_ptr + s_size */
	69
	70	L(Lnormal:)
	71	moveql #32,R(d5)
	72	subl R(cnt),R(d5)
	73
	74	#if (defined (__mc68020__) \|\| defined (__NeXT__) \|\| defined(mc68020))
	75	lea MEM_INDX1(s_ptr,s_size,l,4),R(s_ptr)
	76	lea MEM_INDX1(res_ptr,s_size,l,4),R(res_ptr)
	77	#else /* not mc68000 */
	78	movel R(s_size),R(d0)
	79	asll #2,R(d0)
	80	addl R(s_size),R(s_ptr)
	81	addl R(s_size),R(res_ptr)
	82	#endif
	83	movel MEM_PREDEC(s_ptr),R(d2)
	84	movel R(d2),R(d0)
	85	lsrl R(d5),R(d0) /* compute carry limb */
	86
	87	lsll R(cnt),R(d2)
	88	movel R(d2),R(d1)
	89	subql #1,R(s_size)
	90	beq L(Lend)
	91	lsrl #1,R(s_size)
	92	bcs L(L1)
	93	subql #1,R(s_size)
	94
	95	L(Loop:)
	96	movel MEM_PREDEC(s_ptr),R(d2)
	97	movel R(d2),R(d3)
	98	lsrl R(d5),R(d3)
	99	orl R(d3),R(d1)
	100	movel R(d1),MEM_PREDEC(res_ptr)
	101	lsll R(cnt),R(d2)
	102	L(L1:)
	103	movel MEM_PREDEC(s_ptr),R(d1)
	104	movel R(d1),R(d3)
	105	lsrl R(d5),R(d3)
	106	orl R(d3),R(d2)
	107	movel R(d2),MEM_PREDEC(res_ptr)
	108	lsll R(cnt),R(d1)
	109
	110	dbf R(s_size),L(Loop)
	111	subl #0x10000,R(s_size)
112	bcc L(Loop)
113
114	L(Lend:)
115	movel R(d1),MEM_PREDEC(res_ptr) /* store least significant limb */
116
117	/* Restore used registers from stack frame. */
118	moveml MEM_POSTINC(sp),R(d2)-R(d6)/R(a2)
50e73d13 AS	119	cfi_remember_state
	120	cfi_adjust_cfa_offset (-6*4)
	121	cfi_restore (R(d2))
	122	cfi_restore (R(d3))
	123	cfi_restore (R(d4))
	124	cfi_restore (R(d5))
	125	cfi_restore (R(d6))
	126	cfi_restore (R(a2))
3de9f02e RM	127	rts
	128
	129	/* We loop from least significant end of the arrays, which is only
910e2e14	130	permissible if the source and destination don't overlap, since the
3de9f02e RM	131	function is documented to work for overlapping source and destination. */
3de9f02e RM	132
50e73d13	133	cfi_restore_state
3de9f02e RM	134	L(Lspecial:)
	135	clrl R(d0) /* initialize carry */
	136	eorw #1,R(s_size)
	137	lsrl #1,R(s_size)
	138	bcc L(LL1)
	139	subql #1,R(s_size)
	140
	141	L(LLoop:)
	142	movel MEM_POSTINC(s_ptr),R(d2)
	143	addxl R(d2),R(d2)
	144	movel R(d2),MEM_POSTINC(res_ptr)
	145	L(LL1:)
	146	movel MEM_POSTINC(s_ptr),R(d2)
	147	addxl R(d2),R(d2)
	148	movel R(d2),MEM_POSTINC(res_ptr)
	149
	150	dbf R(s_size),L(LLoop)
	151	addxl R(d0),R(d0) /* save cy in lsb */
	152	subl #0x10000,R(s_size)
	153	bcs L(LLend)
	154	lsrl #1,R(d0) /* restore cy */
	155	bra L(LLoop)
	156
	157	L(LLend:)
	158	/* Restore used registers from stack frame. */
	159	moveml MEM_POSTINC(sp),R(d2)-R(d6)/R(a2)
50e73d13 AS	160	cfi_adjust_cfa_offset (-6*4)
	161	cfi_restore (R(d2))
	162	cfi_restore (R(d3))
	163	cfi_restore (R(d4))
	164	cfi_restore (R(d5))
	165	cfi_restore (R(d6))
	166	cfi_restore (R(a2))
3de9f02e	167	rts
56d7f029	168	END(__mpn_lshift)