1 /* gen-sframe.h - Support for generating SFrame. 2 Copyright (C) 2022-2024 Free Software Foundation, Inc. 3 4 This file is part of GAS, the GNU Assembler. 5 6 GAS is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 any later version. 10 11 GAS is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GAS; see the file COPYING. If not, write to the Free 18 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 19 02110-1301, USA. */ 20 21 #ifndef GENSFRAME_H 22 #define GENSFRAME_H 23 24 #define SFRAME_FRE_ELEM_LOC_REG 0 25 #define SFRAME_FRE_ELEM_LOC_STACK 1 26 27 /* SFrame Frame Row Entry (FRE). 28 29 A frame row entry is a slice of the frame and can be valid for a set of 30 program instructions. It keeps all information needed to retrieve the CFA 31 and the Return Address (RA) if tracked. 32 33 A frame row entry effectively stores accumulated information gathered by 34 interpreting multiple CFI instructions. More precisely, it is a 35 self-sufficient record in its own right. Only the subset of information 36 necessary for unwinding is stored: Given a PC, how to retrieve the CFA and 37 the RA. 38 */ 39 40 struct sframe_row_entry 41 { 42 /* A linked list. */ 43 struct sframe_row_entry *next; 44 45 /* Start and end of the frame row entry. */ 46 symbolS *pc_begin; 47 symbolS *pc_end; 48 49 /* A frame row entry is a merge candidate if new information can be updated 50 on it. */ 51 bool merge_candidate; 52 53 /* Whether the return address is mangled with pauth code. */ 54 bool mangled_ra_p; 55 56 /* Track CFA base (architectural) register ID. */ 57 unsigned int cfa_base_reg; 58 /* Offset from the CFA base register for recovering CFA. */ 59 offsetT cfa_offset; 60 61 /* Track the other register used as base register for CFA. Specify whether 62 it is in register or memory. */ 63 unsigned int base_reg; 64 unsigned int bp_loc; 65 /* If the other register is stashed on stack, note the offset. */ 66 offsetT bp_offset; 67 68 /* Track RA location. Specify whether it is in register or memory. */ 69 unsigned int ra_loc; 70 /* If RA is stashed on stack, note the offset. */ 71 offsetT ra_offset; 72 }; 73 74 /* SFrame Function Description Entry. */ 75 76 struct sframe_func_entry 77 { 78 /* A linked list. */ 79 struct sframe_func_entry *next; 80 81 /* Reference to the FDE created from CFI in dw2gencfi. Some information 82 like the start_address and the segment is made available via this 83 member. */ 84 const struct fde_entry *dw_fde; 85 86 /* Reference to the first FRE for this function. */ 87 struct sframe_row_entry *sframe_fres; 88 89 unsigned int num_fres; 90 }; 91 92 /* SFrame Function Description Entry Translation Context. */ 93 94 struct sframe_xlate_ctx 95 { 96 /* Reference to the FDE created from CFI in dw2gencfi. Information 97 like the FDE start_address, end_address and the cfi insns are 98 made available via this member. */ 99 const struct fde_entry *dw_fde; 100 101 /* List of FREs in the current FDE translation context, bounded by first_fre 102 and last_fre. */ 103 104 /* Keep track of the first FRE for the purpose of restoring state if 105 necessary (for DW_CFA_restore). */ 106 struct sframe_row_entry *first_fre; 107 /* The last FRE in the list. */ 108 struct sframe_row_entry *last_fre; 109 110 /* The current FRE under construction. */ 111 struct sframe_row_entry *cur_fre; 112 /* Remember FRE for an eventual restore. */ 113 struct sframe_row_entry *remember_fre; 114 115 unsigned num_xlate_fres; 116 }; 117 118 /* Error codes for SFrame translation context. */ 119 enum sframe_xlate_err 120 { 121 /* Success. */ 122 SFRAME_XLATE_OK = 0, 123 /* Error. */ 124 SFRAME_XLATE_ERROR = 1, 125 /* Detailed error codes. */ 126 SFRAME_XLATE_ERR_INVAL = -1, 127 SFRAME_XLATE_ERR_NOTREPRESENTED = -2, 128 }; 129 130 /* Callback to create the abi/arch identifier for SFrame section. */ 131 132 unsigned char 133 sframe_get_abi_arch_callback (const char *target_arch, 134 int big_endian_p); 135 136 /* The list of all FDEs with data in SFrame internal representation. */ 137 138 extern struct sframe_func_entry *all_sframe_fdes; 139 140 /* SFrame version specific operations structure. */ 141 142 struct sframe_version_ops 143 { 144 unsigned char format_version; /* SFrame format version. */ 145 /* set SFrame FRE info. */ 146 unsigned char (*set_fre_info) (unsigned int, unsigned int, unsigned int, 147 bool); 148 /* set SFrame Func info. */ 149 unsigned char (*set_func_info) (unsigned int, unsigned int, unsigned int); 150 }; 151 152 /* Generate SFrame stack trace info and prepare contents for the output. 153 outout_sframe () is called at the end of file. */ 154 155 extern void output_sframe (segT sframe_seg); 156 157 #endif /* GENSFRAME_H */ 158