58 lines
972 B
ArmAsm
58 lines
972 B
ArmAsm
/*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; version 2
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* of the License.
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*
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*/
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#include <linux/linkage.h>
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#include <asm/alternative-asm.h>
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#include <asm/frame.h>
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#include <asm/dwarf2.h>
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.text
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/*
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* Inputs:
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* %esi : memory location to compare
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* %eax : low 32 bits of old value
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* %edx : high 32 bits of old value
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* %ebx : low 32 bits of new value
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* %ecx : high 32 bits of new value
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*/
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ENTRY(cmpxchg8b_emu)
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CFI_STARTPROC
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#
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# Emulate 'cmpxchg8b (%esi)' on UP except we don't
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# set the whole ZF thing (caller will just compare
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# eax:edx with the expected value)
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#
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cmpxchg8b_emu:
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pushfl
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cli
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cmpl (%esi), %eax
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jne not_same
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cmpl 4(%esi), %edx
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jne half_same
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movl %ebx, (%esi)
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movl %ecx, 4(%esi)
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popfl
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ret
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not_same:
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movl (%esi), %eax
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half_same:
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movl 4(%esi), %edx
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popfl
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ret
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CFI_ENDPROC
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ENDPROC(cmpxchg8b_emu)
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