x86/util/dwarf-regs.c

1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * dwarf-regs.c : Mapping of DWARF debug register numbers into register names.
4  * Extracted from probe-finder.c
14 #include <dwarf-regs.h>
17  * See arch/x86/kernel/ptrace.c.
20  *  - Since struct pt_regs is defined differently for user and kernel,
22  *    field name of user's pt_regs), we make REG_OFFSET_NAME to accept
23  *    both string name and reg field name.
25  *  - Since accessing x86_32's pt_regs from x86_64 building is difficult
26  *    and vise versa, we simply fill offset with -1, so
33  *  - Order is different from kernel's ptrace.c for get_arch_regstr(). Use
38 	const char *name;  member
42 #define REG_OFFSET_END {.name = NULL, .offset = 0}
45 # define REG_OFFSET_NAME_64(n, r) {.name = n, .offset = offsetof(struct pt_regs, r)}
46 # define REG_OFFSET_NAME_32(n, r) {.name = n, .offset = -1}
48 # define REG_OFFSET_NAME_64(n, r) {.name = n, .offset = -1}
49 # define REG_OFFSET_NAME_32(n, r) {.name = n, .offset = offsetof(struct pt_regs, r)}
66 #define regoffset_table x86_32_regoffset_table
88 #define regoffset_table x86_64_regoffset_table
92 #define ARCH_MAX_REGS ((sizeof(regoffset_table) / sizeof(regoffset_table[0])) - 1)
94 /* Return architecture dependent register string (for kprobe-tracer) */
97 	return (n < ARCH_MAX_REGS) ? regoffset_table[n].name : NULL;  in get_arch_regstr()
100 /* Reuse code from arch/x86/kernel/ptrace.c */
102  * regs_query_register_offset() - query register offset from its name
103  * @name:	the name of a register
106  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
108 int regs_query_register_offset(const char *name)  in regs_query_register_offset()  argument
111 	for (roff = regoffset_table; roff->name != NULL; roff++)  in regs_query_register_offset()
112 		if (!strcmp(roff->name, name))  in regs_query_register_offset()
113 			return roff->offset;  in regs_query_register_offset()
114 	return -EINVAL;  in regs_query_register_offset()
118 	const char *name;  member
142 int get_arch_regnum(const char *name)  in get_arch_regnum()  argument
146 	if (*name != '%')  in get_arch_regnum()
147 		return -EINVAL;  in get_arch_regnum()
150 		if (!strcmp(x86_regidx_table[i].name, name + 1))  in get_arch_regnum()
152 	return -ENOENT;  in get_arch_regnum()