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86effd0dc6
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>
79 lines
1.3 KiB
ArmAsm
79 lines
1.3 KiB
ArmAsm
/*
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* Copyright (C) 2014-15 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(strcmp)
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or r2, r0, r1
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bmsk_s r2, r2, 1
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brne r2, 0, @.Lcharloop
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;;; s1 and s2 are word aligned
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ld.ab r2, [r0, 4]
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mov_s r12, 0x01010101
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ror r11, r12
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.align 4
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.LwordLoop:
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ld.ab r3, [r1, 4]
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;; Detect NULL char in str1
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sub r4, r2, r12
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ld.ab r5, [r0, 4]
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bic r4, r4, r2
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and r4, r4, r11
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brne.d.nt r4, 0, .LfoundNULL
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;; Check if the read locations are the same
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cmp r2, r3
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beq.d .LwordLoop
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mov.eq r2, r5
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;; A match is found, spot it out
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#ifdef __LITTLE_ENDIAN__
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swape r3, r3
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mov_s r0, 1
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swape r2, r2
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#else
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mov_s r0, 1
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#endif
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cmp_s r2, r3
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j_s.d [blink]
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bset.lo r0, r0, 31
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.align 4
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.LfoundNULL:
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#ifdef __BIG_ENDIAN__
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swape r4, r4
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swape r2, r2
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swape r3, r3
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#endif
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;; Find null byte
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ffs r0, r4
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bmsk r2, r2, r0
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bmsk r3, r3, r0
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swape r2, r2
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swape r3, r3
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;; make the return value
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sub.f r0, r2, r3
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mov.hi r0, 1
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j_s.d [blink]
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bset.lo r0, r0, 31
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.align 4
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.Lcharloop:
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ldb.ab r2, [r0, 1]
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ldb.ab r3, [r1, 1]
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nop
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breq r2, 0, .Lcmpend
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breq r2, r3, .Lcharloop
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.align 4
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.Lcmpend:
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j_s.d [blink]
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sub r0, r2, r3
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END_CFI(strcmp)
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