12de3b87aSKai Wang.\" Copyright (c) 2011 Kai Wang 22de3b87aSKai Wang.\" All rights reserved. 32de3b87aSKai Wang.\" 42de3b87aSKai Wang.\" Redistribution and use in source and binary forms, with or without 52de3b87aSKai Wang.\" modification, are permitted provided that the following conditions 62de3b87aSKai Wang.\" are met: 72de3b87aSKai Wang.\" 1. Redistributions of source code must retain the above copyright 82de3b87aSKai Wang.\" notice, this list of conditions and the following disclaimer. 92de3b87aSKai Wang.\" 2. Redistributions in binary form must reproduce the above copyright 102de3b87aSKai Wang.\" notice, this list of conditions and the following disclaimer in the 112de3b87aSKai Wang.\" documentation and/or other materials provided with the distribution. 122de3b87aSKai Wang.\" 132de3b87aSKai Wang.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 142de3b87aSKai Wang.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 152de3b87aSKai Wang.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 162de3b87aSKai Wang.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 172de3b87aSKai Wang.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 182de3b87aSKai Wang.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 192de3b87aSKai Wang.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 202de3b87aSKai Wang.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 212de3b87aSKai Wang.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 222de3b87aSKai Wang.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 232de3b87aSKai Wang.\" SUCH DAMAGE. 242de3b87aSKai Wang.\" 25*ae500c1fSEd Maste.\" $Id: dwarf_add_expr_gen.3 3640 2018-10-14 14:09:13Z jkoshy $ 262de3b87aSKai Wang.\" 272de3b87aSKai Wang.Dd September 9, 2011 282de3b87aSKai Wang.Dt DWARF_ADD_EXPR_GEN 3 29*ae500c1fSEd Maste.Os 302de3b87aSKai Wang.Sh NAME 312de3b87aSKai Wang.Nm dwarf_add_expr_gen 322de3b87aSKai Wang.Nd add an operator to a location expression descriptor 332de3b87aSKai Wang.Sh LIBRARY 342de3b87aSKai Wang.Lb libdwarf 352de3b87aSKai Wang.Sh SYNOPSIS 362de3b87aSKai Wang.In libdwarf.h 372de3b87aSKai Wang.Ft "Dwarf_Unsigned" 382de3b87aSKai Wang.Fo dwarf_add_expr_gen 392de3b87aSKai Wang.Fa "Dwarf_P_Expr expr" 402de3b87aSKai Wang.Fa "Dwarf_Small opcode" 412de3b87aSKai Wang.Fa "Dwarf_Unsigned val1" 422de3b87aSKai Wang.Fa "Dwarf_Unsigned val2" 432de3b87aSKai Wang.Fa "Dwarf_Error *err" 442de3b87aSKai Wang.Fc 452de3b87aSKai Wang.Sh DESCRIPTION 462de3b87aSKai WangFunction 472de3b87aSKai Wang.Fn dwarf_add_expr_gen 482de3b87aSKai Wangadds a location expression operator to the location expression 492de3b87aSKai Wangdescriptor referenced by argument 502de3b87aSKai Wang.Ar expr . 512de3b87aSKai Wang.Pp 522de3b87aSKai WangArgument 532de3b87aSKai Wang.Ar expr 542de3b87aSKai Wangshould reference a location expression descriptor allocated using 552de3b87aSKai Wangthe function 562de3b87aSKai Wang.Xr dwarf_new_expr 3 . 572de3b87aSKai Wang.Pp 582de3b87aSKai WangArgument 592de3b87aSKai Wang.Ar opcode 602de3b87aSKai Wangspecifies the operation code of the location expression operator. 612de3b87aSKai WangValid values for this argument are those denoted by the 622de3b87aSKai Wang.Dv DW_OP_ Ns * 632de3b87aSKai Wangconstants defined in 642de3b87aSKai Wang.In libdwarf.h . 652de3b87aSKai Wang.Pp 662de3b87aSKai WangTo generate a 672de3b87aSKai Wang.Dv DW_OP_addr 682de3b87aSKai Wangoperation, application code should instead use 692de3b87aSKai Wang.Xr dwarf_add_expr_addr_b 3 . 702de3b87aSKai Wang.Pp 712de3b87aSKai WangArgument 722de3b87aSKai Wang.Ar val1 732de3b87aSKai Wangspecifies the first operand of the location expression operator. 742de3b87aSKai Wang.Pp 752de3b87aSKai WangArgument 762de3b87aSKai Wang.Ar val2 772de3b87aSKai Wangspecifies the second operand of the location expression operator. 782de3b87aSKai Wang.Pp 792de3b87aSKai WangIf argument 802de3b87aSKai Wang.Ar err 812de3b87aSKai Wangis not NULL, it will be used to store error information in case 822de3b87aSKai Wangof an error. 832de3b87aSKai Wang.Sh RETURN VALUES 842de3b87aSKai WangOn success, function 852de3b87aSKai Wang.Fn dwarf_add_expr_gen 862de3b87aSKai Wangreturns the size in bytes of the location expression byte stream 872de3b87aSKai Wanggenerated. 882de3b87aSKai WangIn case of an error, function 892de3b87aSKai Wang.Fn dwarf_add_expr_gen 902de3b87aSKai Wangreturns 912de3b87aSKai Wang.Dv DW_DLV_NOCOUNT 922de3b87aSKai Wangand sets the argument 932de3b87aSKai Wang.Ar err . 942de3b87aSKai Wang.Sh ERRORS 952de3b87aSKai WangFunction 962de3b87aSKai Wang.Fn dwarf_add_expr_gen 972de3b87aSKai Wangcan fail with: 982de3b87aSKai Wang.Bl -tag -width ".Bq Er DW_DLE_LOC_EXPR_BAD" 992de3b87aSKai Wang.It Bq Er DW_DLE_ARGUMENT 1002de3b87aSKai WangArgument 1012de3b87aSKai Wang.Ar expr 1022de3b87aSKai Wangwas NULL. 1032de3b87aSKai Wang.It Bq Er DW_DLE_LOC_EXPR_BAD 1042de3b87aSKai WangThe operation code specified in argument 1052de3b87aSKai Wang.Ar opcode 1062de3b87aSKai Wangwas invalid. 1072de3b87aSKai Wang.It Bq Er DW_DLE_MEMORY 1082de3b87aSKai WangAn out of memory condition was encountered during the execution of 1092de3b87aSKai Wangthe function. 1102de3b87aSKai Wang.El 1112de3b87aSKai Wang.Sh SEE ALSO 1122de3b87aSKai Wang.Xr dwarf 3 , 1132de3b87aSKai Wang.Xr dwarf_add_AT_location_expr 3 , 1142de3b87aSKai Wang.Xr dwarf_add_expr_addr 3 , 1152de3b87aSKai Wang.Xr dwarf_add_expr_addr_b 3 , 1162de3b87aSKai Wang.Xr dwarf_expr_current_offset 3 , 1172de3b87aSKai Wang.Xr dwarf_expr_into_block 3 , 1182de3b87aSKai Wang.Xr dwarf_new_expr 3 119