1.\" $NetBSD: dwarf_get_fde_info_for_reg.3,v 1.6 2024/03/03 17:37:31 christos Exp $ 2.\" 3.\" Copyright (c) 2011 Kai Wang 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" Id: dwarf_get_fde_info_for_reg.3 3962 2022-03-12 15:56:10Z jkoshy 28.\" 29.Dd June 4, 2011 30.Dt DWARF_GET_FDE_INFO_FOR_REG 3 31.Os 32.Sh NAME 33.Nm dwarf_get_fde_info_for_reg 34.Nd retrieve register rule 35.Sh LIBRARY 36.Lb libdwarf 37.Sh SYNOPSIS 38.In libdwarf.h 39.Ft int 40.Fo dwarf_get_fde_info_for_reg 41.Fa "Dwarf_Fde fde" 42.Fa "Dwarf_Half table_column" 43.Fa "Dwarf_Addr pc" 44.Fa "Dwarf_Signed *offset_relevant" 45.Fa "Dwarf_Signed *register_num" 46.Fa "Dwarf_Signed *offset" 47.Fa "Dwarf_Addr *row_pc" 48.Fa "Dwarf_Error *error" 49.Fc 50.Sh DESCRIPTION 51Function 52.Fn dwarf_get_fde_info_for_reg 53retrieves a register rule from the register rule table associated with 54a given FDE descriptor, given a program counter address and rule 55column number. 56.Pp 57Argument 58.Fa fde 59should reference a valid DWARF FDE descriptor. 60.Pp 61Arugment 62.Fa table_column 63should hold the column number of the register rule desired. 64.Pp 65Argument 66.Fa pc 67should hold the program counter address to be used to locate the 68desired register rule row. 69.Pp 70On successful execution, 71.Fn dwarf_get_fde_info_for_reg 72stores information about the register rule found into the locations 73pointed to by the arguments 74.Fa offset_relevant , 75.Fa register_num , 76.Fa offset 77and 78.Fa row_pc . 79.Pp 80If there is an offset value associated with the register rule, 81the location pointed to by argument 82.Fa offset_relevant 83will be set to 1. 84.Pp 85Argument 86.Fa register_num 87should point to a location which will hold the register number associated 88with the register rule. 89.Pp 90Argument 91.Fa offset 92should point to a location which will be set to the offset value 93associated with the register rule, or to 0 if the register rule 94does not have an offset value. 95.Pp 96Argument 97.Fa row_pc 98should point to a location which will be set to the lowest program 99counter address associated with the register rule found. 100.Pp 101If argument 102.Fa err 103is not 104.Dv NULL , 105it will be used to return an error descriptor in case of an error. 106.Ss COMPATIBILITY 107Function 108.Fn dwarf_get_fde_info_for_reg 109is deprecated since it only supports DWARF2 frame sections. 110Applications should instead use function 111.Xr dwarf_get_fde_info_for_reg3 3 112which supports both DWARF2 and DWARF3 frame sections. 113.Sh RETURN VALUES 114Function 115.Fn dwarf_get_fde_info_for_reg 116returns 117.Dv DW_DLV_OK 118when it succeeds. 119In case of an error, it returns 120.Dv DW_DLV_ERROR 121and sets the argument 122.Fa err . 123.Sh ERRORS 124Function 125.Fn dwarf_get_fde_info_for_reg 126can fail with: 127.Bl -tag -width ".Bq Er DW_DLE_FRAME_TABLE_COL_BAD" 128.It Bq Er DW_DLE_ARGUMENT 129One of the arguments 130.Fa fde , 131.Fa offset_relevant , 132.Fa register_num , 133.Fa offset 134or 135.Fa row_pc 136was 137.Dv NULL . 138.It Bq Er DW_DLE_FRAME_TABLE_COL_BAD 139The column number provided in argument 140.Fa table_column 141was too large. 142.It Bq Er DW_DLE_PC_NOT_IN_FDE_RANGE 143The program counter value provided in argument 144.Fa pc 145did not fall in the range covered by argument 146.Fa fde . 147.El 148.Sh SEE ALSO 149.Xr dwarf 3 , 150.Xr dwarf_get_fde_at_pc 3 , 151.Xr dwarf_get_fde_info_for_all_regs 3 , 152.Xr dwarf_get_fde_info_for_all_regs3 3 , 153.Xr dwarf_get_fde_info_for_cfa_reg3 3 , 154.Xr dwarf_get_fde_info_for_reg3 3 , 155.Xr dwarf_get_fde_n 3 , 156.Xr dwarf_set_frame_cfa_value 3 , 157.Xr dwarf_set_frame_rule_initial_value 3 , 158.Xr dwarf_set_frame_rule_table_size 3 , 159.Xr dwarf_set_frame_same_value 3 , 160.Xr dwarf_set_frame_undefined_value 3 161