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	2006-01-05 H.J. Lu <hongjiu.lu@intel.com> [BZ #2013] * sysdeps/ia64/memccpy.S: Properly handle recovery for predicated speculative load.
		
			
				
	
	
		
			251 lines
		
	
	
		
			6.7 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			251 lines
		
	
	
		
			6.7 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /* Optimized version of the memccpy() function.
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|    This file is part of the GNU C Library.
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|    Copyright (C) 2000,2001,2003,2006 Free Software Foundation, Inc.
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|    Contributed by Dan Pop <Dan.Pop@cern.ch>.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, write to the Free
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|    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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|    02111-1307 USA.  */
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| 
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| /* Return: a pointer to the next byte after char in dest or NULL
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| 
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|    Inputs:
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|         in0:    dest
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|         in1:    src
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|   	in2:	char
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|         in3:    byte count
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| 
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|    This implementation assumes little endian mode (UM.be = 0).
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| 
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|    This implementation assumes that it is safe to do read ahead
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|    in the src block, without getting beyond its limit.  */
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| 
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| #include <sysdep.h>
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| #undef ret
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| 
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| #define OP_T_THRES 	16
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| #define OPSIZ 		8
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| 
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| #define saved_pr	r17
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| #define saved_lc	r18
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| #define dest		r19
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| #define src		r20
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| #define len		r21
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| #define asrc		r22
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| #define tmp		r23
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| #define char		r24
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| #define charx8		r25
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| #define saved_ec	r26
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| #define sh2		r28
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| #define	sh1		r29
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| #define loopcnt		r30
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| #define	value		r31
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| 
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| #ifdef GAS_ALIGN_BREAKS_UNWIND_INFO
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| /* Manually force proper loop-alignment.  Note: be sure to
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|    double-check the code-layout after making any changes to
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|    this routine! */
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| # define ALIGN(n)	{ nop 0 }
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| #else
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| # define ALIGN(n)	.align n
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| #endif
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| 
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| ENTRY(memccpy)
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| 	.prologue
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| 	alloc 	r2 = ar.pfs, 4, 40 - 4, 0, 40
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| 
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| #include "softpipe.h"
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| 	.rotr	r[MEMLAT + 7], tmp1[4], tmp2[4], val[4], tmp3[2], pos0[2]
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| 	.rotp	p[MEMLAT + 6 + 1]
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| 
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| 	mov	ret0 = r0		// return NULL if no match
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| 	.save pr, saved_pr
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| 	mov	saved_pr = pr		// save the predicate registers
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| 	mov 	dest = in0		// dest
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| 	.save ar.lc, saved_lc
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|         mov 	saved_lc = ar.lc	// save the loop counter
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|         mov 	saved_ec = ar.ec	// save the loop counter
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| 	.body
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| 	mov 	src = in1		// src
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| 	extr.u	char = in2, 0, 8	// char
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| 	mov	len = in3		// len
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| 	sub	tmp = r0, in0		// tmp = -dest
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| 	cmp.ne	p7, p0 = r0, r0		// clear p7
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| 	;;
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| 	and	loopcnt = 7, tmp	// loopcnt = -dest % 8
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| 	cmp.ge	p6, p0 = OP_T_THRES, len	// is len <= OP_T_THRES
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| 	mov	ar.ec = 0		// ec not guaranteed zero on entry
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| (p6)	br.cond.spnt	.cpyfew		// copy byte by byte
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| 	;;
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| 	cmp.eq	p6, p0 = loopcnt, r0
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| 	mux1	charx8 = char, @brcst
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| (p6)	br.cond.sptk .dest_aligned
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| 	sub	len = len, loopcnt	// len -= -dest % 8
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| 	adds	loopcnt = -1, loopcnt	// --loopcnt
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| 	;;
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| 	mov	ar.lc = loopcnt
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| .l1:					// copy -dest % 8 bytes
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| 	ld1	value = [src], 1	// value = *src++
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| 	;;
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| 	st1	[dest] = value, 1	// *dest++ = value
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| 	cmp.eq	p6, p0 = value, char
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| (p6)	br.cond.spnt .foundit
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| 	br.cloop.dptk .l1
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| .dest_aligned:
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| 	and	sh1 = 7, src 		// sh1 = src % 8
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| 	and	tmp = -8, len   	// tmp = len & -OPSIZ
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| 	and	asrc = -8, src		// asrc = src & -OPSIZ  -- align src
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| 	shr.u	loopcnt = len, 3	// loopcnt = len / 8
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| 	and	len = 7, len ;;		// len = len % 8
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| 	shl	sh1 = sh1, 3		// sh1 = 8 * (src % 8)
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| 	adds	loopcnt = -1, loopcnt	// --loopcnt
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| 	mov     pr.rot = 1 << 16 ;;	// set rotating predicates
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| 	sub	sh2 = 64, sh1		// sh2 = 64 - sh1
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| 	mov	ar.lc = loopcnt		// set LC
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| 	cmp.eq  p6, p0 = sh1, r0 	// is the src aligned?
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| (p6)    br.cond.sptk .src_aligned ;;
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| 	add	src = src, tmp		// src += len & -OPSIZ
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| 	mov	ar.ec = MEMLAT + 6 + 1 	// six more passes needed
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| 	ld8	r[1] = [asrc], 8 	// r[1] = w0
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| 	cmp.ne	p6, p0 = r0, r0	;;	// clear p6
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| 	ALIGN(32)
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| .l2:
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| (p[0])		ld8.s	r[0] = [asrc], 8		// r[0] = w1
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| (p[MEMLAT])	shr.u	tmp1[0] = r[1 + MEMLAT], sh1	// tmp1 = w0 >> sh1
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| (p[MEMLAT])	shl	tmp2[0] = r[0 + MEMLAT], sh2  	// tmp2 = w1 << sh2
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| (p[MEMLAT+4])	xor	tmp3[0] = val[1], charx8
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| (p[MEMLAT+5])	czx1.r	pos0[0] = tmp3[1]
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| (p[MEMLAT+6])	chk.s	r[6 + MEMLAT], .recovery1	// our data isn't
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| 							// valid - rollback!
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| (p[MEMLAT+6])	cmp.ne	p6, p0 = 8, pos0[1]
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| (p6)		br.cond.spnt	.gotit
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| (p[MEMLAT+6])	st8	[dest] = val[3], 8		// store val to dest
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| (p[MEMLAT+3])	or	val[0] = tmp1[3], tmp2[3] 	// val = tmp1 | tmp2
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| 		br.ctop.sptk    .l2
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| 		br.cond.sptk .cpyfew
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| 
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| .src_aligned:
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| 		cmp.ne  p6, p0 = r0, r0			// clear p6
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| 		mov     ar.ec = MEMLAT + 2 + 1 ;;	// set EC
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| .l3:
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| (p[0])		ld8.s	r[0] = [src], 8
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| (p[MEMLAT])	xor	tmp3[0] = r[MEMLAT], charx8
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| (p[MEMLAT+1])	czx1.r	pos0[0] = tmp3[1]
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| (p[MEMLAT+2])	cmp.ne	p7, p0 = 8, pos0[1]
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| (p[MEMLAT+2])	chk.s	r[MEMLAT+2], .recovery2
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| (p7)		br.cond.spnt	.gotit
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| .back2:
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| (p[MEMLAT+2])	st8	[dest] = r[MEMLAT+2], 8
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| 		br.ctop.dptk .l3
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| .cpyfew:
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| 	cmp.eq	p6, p0 = len, r0	// is len == 0 ?
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| 	adds	len = -1, len		// --len;
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| (p6)	br.cond.spnt	.restore_and_exit ;;
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| 	mov	ar.lc = len
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| .l4:
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| 	ld1	value = [src], 1
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| 	;;
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| 	st1	[dest] = value, 1
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| 	cmp.eq	p6, p0 = value, char
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| (p6)	br.cond.spnt .foundit
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| 	br.cloop.dptk	.l4 ;;
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| .foundit:
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| (p6)	mov	ret0 = dest
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| .restore_and_exit:
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| 	mov     pr = saved_pr, -1    	// restore the predicate registers
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| 	mov 	ar.lc = saved_lc	// restore the loop counter
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| 	mov 	ar.ec = saved_ec ;;	// restore the epilog counter
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| 	br.ret.sptk.many b0
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| .gotit:
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| 	.pred.rel "mutex" p6, p7
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| (p6)	mov	value = val[3]		// if coming from l2
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| (p7)	mov	value = r[MEMLAT+2]	// if coming from l3
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| 	mov	ar.lc = pos0[1] ;;
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| .l5:
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| 	extr.u	tmp = value, 0, 8 ;;
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| 	st1	[dest] = tmp, 1
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| 	shr.u	value = value, 8
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| 	br.cloop.sptk .l5 ;;
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| 	mov 	ret0 = dest
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| 	mov	pr = saved_pr, -1
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| 	mov	ar.lc = saved_lc
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| 	br.ret.sptk.many b0
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| 
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| .recovery1:
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| #if MEMLAT != 6
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| # error "MEMLAT must be 6!"
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| #endif
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| 	adds	src = -8, asrc
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| 	mov	loopcnt = ar.lc
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| 	mov	tmp = ar.ec
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| 	;;
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| (p[0])	adds	src = -8, src
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| 	;;
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| (p[1])	adds	src = -8, src
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| 	sub	sh1 = (MEMLAT + 6 + 1), tmp
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| 	;;
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| (p[2])	adds	src = -8, src
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| 	;;
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| (p[3])	adds	src = -8, src
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| 	shl	loopcnt = loopcnt, 3
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| 	;;
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| (p[4])	adds	src = -8, src
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| 	;;
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| (p[5])	adds	src = -8, src
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| 	shl	sh1 = sh1, 3
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| 	;;
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| (p[6])	adds	src = -8, src
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| 	;;
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| (p[7])	adds	src = -8, src
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| 	shl	tmp = tmp, 3
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| 	;;
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| (p[8])	adds	src = -8, src
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| 	;;
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| (p[9])	adds	src = -8, src
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| 	shr.u	sh2 = sh2, 3
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| 	;;
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| (p[10])	adds	src = -8, src
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| 	;;
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| (p[11])	adds	src = -8, src
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| 	add	len = len, loopcnt
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| 	;;
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| 	sub	src = src, sh2
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| 	;;
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| 	add	len = tmp, len
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| 	add	src = sh1, src
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| 	br.cond.sptk .cpyfew
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| 
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| .recovery2:
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| #if MEMLAT != 6
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| # error "MEMLAT must be 6!"
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| #endif
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| 	add	tmp = -8, src
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| (p7)	br.cond.spnt .gotit
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| 	;;
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| (p[0])	add	tmp = -8, tmp ;;
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| (p[1])	add	tmp = -8, tmp ;;
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| (p[2])	add	tmp = -8, tmp ;;
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| (p[3])	add	tmp = -8, tmp ;;
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| (p[4])	add	tmp = -8, tmp ;;
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| (p[5])	add	tmp = -8, tmp ;;
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| (p[6])	add	tmp = -8, tmp ;;
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| (p[7])	add	tmp = -8, tmp ;;
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| 	ld8	r[MEMLAT+2] = [tmp] ;;
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| 	xor	pos0[1] = r[MEMLAT+2], charx8 ;;
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| 	czx1.r	pos0[1] = pos0[1] ;;
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| 	cmp.ne	p7, p6 = 8, pos0[1]
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| (p7)	br.cond.spnt .gotit
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| 	br.cond.sptk .back2
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| END(memccpy)
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