#ifndef _ASM_X86_UNWIND_HINTS_H
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#define _ASM_X86_UNWIND_HINTS_H
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#include "orc_types.h"
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#ifdef __ASSEMBLY__
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/*
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* In asm, there are two kinds of code: normal C-type callable functions and
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* the rest. The normal callable functions can be called by other code, and
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* don't do anything unusual with the stack. Such normal callable functions
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* are annotated with the ENTRY/ENDPROC macros. Most asm code falls in this
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* category. In this case, no special debugging annotations are needed because
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* objtool can automatically generate the ORC data for the ORC unwinder to read
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* at runtime.
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*
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* Anything which doesn't fall into the above category, such as syscall and
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* interrupt handlers, tends to not be called directly by other functions, and
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* often does unusual non-C-function-type things with the stack pointer. Such
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* code needs to be annotated such that objtool can understand it. The
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* following CFI hint macros are for this type of code.
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*
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* These macros provide hints to objtool about the state of the stack at each
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* instruction. Objtool starts from the hints and follows the code flow,
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* making automatic CFI adjustments when it sees pushes and pops, filling out
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* the debuginfo as necessary. It will also warn if it sees any
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* inconsistencies.
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*/
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.macro UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=0 type=ORC_TYPE_CALL end=0
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#ifdef CONFIG_STACK_VALIDATION
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.Lunwind_hint_ip_\@:
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.pushsection .discard.unwind_hints
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/* struct unwind_hint */
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.long .Lunwind_hint_ip_\@ - .
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.short \sp_offset
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.byte \sp_reg
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.byte \type
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.byte \end
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.balign 4
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.popsection
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#endif
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.endm
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.macro UNWIND_HINT_EMPTY
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UNWIND_HINT sp_reg=ORC_REG_UNDEFINED end=1
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.endm
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.macro UNWIND_HINT_REGS base=%rsp offset=0 indirect=0 extra=1 iret=0
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.if \base == %rsp
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.if \indirect
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.set sp_reg, ORC_REG_SP_INDIRECT
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.else
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.set sp_reg, ORC_REG_SP
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.endif
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.elseif \base == %rbp
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.set sp_reg, ORC_REG_BP
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.elseif \base == %rdi
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.set sp_reg, ORC_REG_DI
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.elseif \base == %rdx
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.set sp_reg, ORC_REG_DX
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.elseif \base == %r10
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.set sp_reg, ORC_REG_R10
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.else
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.error "UNWIND_HINT_REGS: bad base register"
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.endif
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.set sp_offset, \offset
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.if \iret
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.set type, ORC_TYPE_REGS_IRET
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.elseif \extra == 0
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.set type, ORC_TYPE_REGS_IRET
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.set sp_offset, \offset + (16*8)
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.else
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.set type, ORC_TYPE_REGS
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.endif
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UNWIND_HINT sp_reg=sp_reg sp_offset=sp_offset type=type
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.endm
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.macro UNWIND_HINT_IRET_REGS base=%rsp offset=0
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UNWIND_HINT_REGS base=\base offset=\offset iret=1
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.endm
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.macro UNWIND_HINT_FUNC sp_offset=8
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UNWIND_HINT sp_offset=\sp_offset
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.endm
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#else /* !__ASSEMBLY__ */
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#define UNWIND_HINT(sp_reg, sp_offset, type, end) \
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"987: \n\t" \
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".pushsection .discard.unwind_hints\n\t" \
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/* struct unwind_hint */ \
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".long 987b - .\n\t" \
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".short " __stringify(sp_offset) "\n\t" \
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".byte " __stringify(sp_reg) "\n\t" \
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".byte " __stringify(type) "\n\t" \
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".byte " __stringify(end) "\n\t" \
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".balign 4 \n\t" \
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".popsection\n\t"
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#define UNWIND_HINT_SAVE UNWIND_HINT(0, 0, UNWIND_HINT_TYPE_SAVE, 0)
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#define UNWIND_HINT_RESTORE UNWIND_HINT(0, 0, UNWIND_HINT_TYPE_RESTORE, 0)
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#endif /* __ASSEMBLY__ */
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#endif /* _ASM_X86_UNWIND_HINTS_H */
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