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	This uses a new set of annoations viz. ENTRY_CFI/END_CFI to enabel cfi
ops generation.
Note that we didn't change the normal ENTRY/EXIT as we don't actually
want unwind info in the trap/exception/interrutp handlers which use
these, as unwinder then gets confused (it keeps recursing vs. stopping).
Semantically these are leaf routines and unwinding should stop when it
hits those routines.
Before
------
    28.52%     1.19%          9929  hackbench  libuClibc-1.0.17.so   [.] __write_nocancel
            |
            ---__write_nocancel
               |--8.95%--EV_Trap
               |           --8.25%--sys_write
               |                     |--3.93%--sock_write_iter
     ...
               |--2.62%--memset   <==== [LEAF entry as no unwind info]
                         ^^^^^^
After
-----
    29.46%     1.24%         13622  hackbench  libuClibc-1.0.17.so   [.] __write_nocancel
            |
            ---__write_nocancel
               |--9.31%--EV_Trap
               |           --8.62%--sys_write
               |                     |--4.17%--sock_write_iter
     ...
               |--6.19%--sys_write
               |           --6.19%--sock_write_iter
               |                     unix_stream_sendmsg
               |                     |--1.62%--sock_alloc_send_pskb
               |                     |--0.89%--sock_def_readable
               |                     |--0.88%--_raw_spin_unlock_irqrestore
               |                     |--0.69%--memset
               |                     |         ^^^^^^     <==== [now in proper callframe]
               |                     |
               |                      --0.52%--skb_copy_datagram_from_iter
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
		
	
			
		
			
				
	
	
		
			66 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
/*
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 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License version 2 as
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 * published by the Free Software Foundation.
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 */
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#include <linux/linkage.h>
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ENTRY_CFI(memcpy)
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	or	r3,r0,r1
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	asl_s	r3,r3,30
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	mov_s	r5,r0
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	brls.d	r2,r3,.Lcopy_bytewise
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	sub.f	r3,r2,1
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	ld_s	r12,[r1,0]
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	asr.f	lp_count,r3,3
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	bbit0.d	r3,2,.Lnox4
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	bmsk_s	r2,r2,1
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	st.ab	r12,[r5,4]
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	ld.a	r12,[r1,4]
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.Lnox4:
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	lppnz	.Lendloop
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	ld_s	r3,[r1,4]
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	st.ab	r12,[r5,4]
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	ld.a	r12,[r1,8]
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	st.ab	r3,[r5,4]
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.Lendloop:
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	breq	r2,0,.Last_store
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	ld	r3,[r5,0]
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#ifdef __LITTLE_ENDIAN__
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	add3	r2,-1,r2
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	; uses long immediate
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	xor_s	r12,r12,r3
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	bmsk	r12,r12,r2
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    xor_s	r12,r12,r3
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#else /* BIG ENDIAN */
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	sub3	r2,31,r2
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	; uses long immediate
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        xor_s	r3,r3,r12
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        bmsk	r3,r3,r2
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        xor_s	r12,r12,r3
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#endif /* ENDIAN */
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.Last_store:
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	j_s.d	[blink]
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	st	r12,[r5,0]
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	.balign	4
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.Lcopy_bytewise:
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	jcs	[blink]
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	ldb_s	r12,[r1,0]
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	lsr.f	lp_count,r3
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	bhs_s	.Lnox1
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	stb.ab	r12,[r5,1]
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	ldb.a	r12,[r1,1]
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.Lnox1:
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	lppnz	.Lendbloop
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	ldb_s	r3,[r1,1]
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	stb.ab	r12,[r5,1]
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	ldb.a	r12,[r1,2]
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	stb.ab	r3,[r5,1]
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.Lendbloop:
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	j_s.d	[blink]
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	stb	r12,[r5,0]
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END_CFI(memcpy)
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