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DWARF_GET_FDE_INFO_FOR_CFA_REGS3(3) FreeBSD Library Functions Manual
NAME
dwarf_get_fde_info_for_cfa_regs3 - retrieve a CFA register rule
LIBRARY
DWARF Access Library (libdwarf, -ldwarf)
SYNOPSIS
#include <libdwarf.h>
int
dwarf_get_fde_info_for_cfa_regs3(Dwarf_Fde fde, Dwarf_Addr pc,
Dwarf_Small *type, Dwarf_Signed *offset_relevant,
Dwarf_Signed *register_num, Dwarf_Signed *offset_or_block_len,
Dwarf_Ptr *block_ptr, Dwarf_Addr *row_pc, Dwarf_Error *err);
DESCRIPTION
Function dwarf_get_fde_info_for_cfa_reg3() retrieves the CFA register
rule for a given program counter address from the register rule table
associated with an FDE descriptor.
Argument fde should reference a valid DWARF FDE descriptor.
Argument pc should hold the program counter address to be used to locate
the desired register rule row.
On successful execution, dwarf_get_fde_info_for_cfa_reg3() stores
information about the CFA register rule found into the locations pointed
to by the arguments type, offset_relevant, register_num,
offset_or_block_len, block_ptr and row_pc.
Argument type should point to a location which will hold the type code of
the register rule found. The returned value is one of the DW_EXPR_*
contants defined in the header file <libdwarf.h>.
If there is an offset value associated with the CFA register rule, the
location pointed to by argument offset_relevant will be set to 1.
Argument register_num should point to a location which will hold the
register number associated with the CFA register rule.
If the CFA register rule is of type DW_EXPR_OFFSET or DW_EXPR_VAL_OFFSET,
the location pointed to by argument offset_or_block_len will be set to
the offset value associated with the register rule, or to 0 if the
register rule does not have an offset value. If the type code is
DW_EXPR_EXPRESSION or DW_EXPR_VAL_EXPRESSION, the location pointed to by
argument offset_or_block_len will be set to the length in bytes of the
DWARF expression block associated with the register rule.
Argument block_ptr should point to a location which will be set to a
pointer to the content of the DWARF expression block associated with the
CFA register rule.
Argument row_pc should point to a location which will be set to the
lowest program counter address associated with the register rule found.
If argument err is not NULL, it will be used to return an error
descriptor in case of an error.
Function dwarf_get_fde_info_for_cfa_reg3() can fail with:
[DW_DLE_ARGUMENT] One of the arguments block_ptr, fde,
offset_or_block_len, offset_relevant,
register_num, row_pc, or type was NULL.
[DW_DLE_PC_NOT_IN_FDE_RANGE] The program counter value provided in
argument pc did not fall in the range
covered by argument fde.
SEE ALSO
dwarf(3), dwarf_get_fde_at_pc(3), dwarf_get_fde_info_for_all_regs(3),
dwarf_get_fde_info_for_all_regs3(3), dwarf_get_fde_info_for_reg(3),
dwarf_get_fde_info_for_reg3(3), dwarf_get_fde_n(3),
dwarf_set_frame_cfa_value(3), dwarf_set_frame_rule_initial_value(3),
dwarf_set_frame_rule_table_size(3), dwarf_set_frame_same_value(3),
dwarf_set_frame_undefined_value(3)
FreeBSD 14.0-RELEASE-p11 June 12, 2011 FreeBSD 14.0-RELEASE-p11