XLATE_EXPAND_REG_INFO(3E)XLATE_EXPAND_REG_INFO(3E)NAME
xlate_expand_reg_info: xlate_expand_reg_info2 - expand register
instructions
SYNOPSIS
#include <elf.h>
#include <libelf.h>
#include <dwarf.h>
#include <libdwarf.h>
#include <cmplrs/xlate.h>
#include <libXlate.h>
int xlate_expand_reg_info(xlate_table_con con_table_ptr,
Elf64_Xword *num_instrs,
xlate_reg_instr **instructions
);
int xlate_expand_reg_info2(xlate_table_con con_table_ptr,
Elf64_Xword *num_instrs,
xlate_reg_instr2 **instructions
);
DESCRIPTION
These are useful for programs like elfdump(1) to show the actual contents
of the register location expressions. These are otherwise very useful.
The functions and the values returned throught the pointers are identical
except that xlate_reg_instr2 has an extra field in the definition. The
extra field, sr_instr_offset, is the byte offset in the register
instruction stream of the first byte of the particular register
instruction.
Aside from the additional field in the structure the functions are
identical.
xlate_reg_instr is now considered obsolete. Applications should cease
using it in favor of xlate_reg_instr2.
Applications desiring the fastest possible speed will want to call
xlate_expand_reg_info2 rather than xlate_expand_reg_info as the former is
slightly faster (the latter is implemented by mallocing another array and
copying portions of the xlate_reg_instr2 array and it is the malloc and
copying that slows xlate_reg_instr down in this implementation).
The arguments of xlate_expand_reg_info and xlate_expand_reg_info2 are:
con_table_ptr
which must be a valid open handle on a translation section.
The following arguments are pointers thru which values are returned.
num_instrs
The value is the number of elements in the instructions array.
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XLATE_EXPAND_REG_INFO(3E)XLATE_EXPAND_REG_INFO(3E)
instructions
The value is a pointer to an array of xlate_reg_instr structs.
This array must be free(2)d by the application to avoid memory
leakage.
See xlate(4) for detailed information on the way each element of this
array is actually filled out. Each element of the array contains
sr_op which is an 8-bit op-code possibly ORd with data.
sr_val1 Which is a 64-bit value whose meaning depends on sr_op .
sr_val2 Which is a 64-bit value whose meaning depends on sr_op .
sr_instr_offset
appears only in the xlate_reg_instr2 version and is the byte
offset of the sr_op in the register instruction byte stream
(before unpacking the byte stream).
A sample use is:
int result;
xlate_reg_instr2 *instructions;
Elf64_Xword num_instrs;
result = xlate_expand_reg_info2(con_table,
&num_instrs,
&instructions);
for(i = 0; i < num_instrs; ++i)
{
printf("%d %lld %lld %ld0,
(int)instructions[i].sr_op,
(long long)instructions[i].sr_val1,
(long long)instructions[i].sr_val2,
(long)instructions[i].sr_val2,
}
free(instructions);
FILES
/usr/include/libXlate.h
/usr/include/cmplrs/xlate.h
/usr/include/elf.h
/usr/include/dwarf.h
/usr/include/libdwarf.h
/usr/lib/libelfutil.a
DIAGNOSTICS
Returns XLATE_TB_STATUS_NO_ERROR (0) on success. In case of error, a
negative number is returned indicating the error. In case of error,
nothing is returned thru the pointer arguments which would return values
on successful call (values might have been changed thru these pointers
but any such changes are not meaningful).
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XLATE_EXPAND_REG_INFO(3E)XLATE_EXPAND_REG_INFO(3E)
XLATE_TB_STATUS_NO_REG_INFO
meaning that there is no register info available. Typically,
this means the translation was done by cord(1). This is really
not an error. It is a special status indicator applications need
to anticipate.
XLATE_TB_STATUS_INVALID_TABLE
means that the tab argument is not a valid open consumer table or
that the data pointed at has been corrupted by a malloc arena
corruption.
XLATE_TB_STATUS_ALLOC_FAIL
A call to malloc() or realloc() failed.
XLATE_TB_STATUS_BAD_REG_VAL
means that the register number (somewhere in the table) is too
large to be used as an index into the Dwarf_Regtable array (see
<libdwarf.h>). This is either a memory corruption, a bogus
register area on the Elf xlate section, or an internal logic
error in the internals of this libelfutil function. Should never
happen.
XLATE_TB_STATUS_BAD_FRAME_OP
means that the Dwarf frame op code is not one of the ones
expected. This is data corruption or an internal error in this
libelfutil function. Should never happen.
XLATE_TB_STATUS_REG_REQUEST_BOGUS
This is an internal error in this libelfutil function. Should
never happen.
SEE ALSOlibelfutil(5), xlate(4), xlate_get_reg_rule(3e), xlate_init_fd(3e),
xlate_finish(3e), xlate_pro_init(3e), xlate_pro_finish(3e), DWARF
Debugging Information Format , A Consumer Library Interface to DWARF
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