[PATCH v5 1/3] disass: Add /x modifier to print offsets in hex
fam@euphon.net
fam@euphon.net
Fri Sep 25 19:51:06 GMT 2020
From: Fam Zheng <famzheng@amazon.com>
Backtrace messages printed by Linux kernel and Xen have hex offsets,
e.g.:
(XEN) Xen call trace:
(XEN) [<ffff82d0402eefbb>] R guest_walk_tables_2_levels+0x189/0x66d
(XEN) [<ffff82d0402edbbd>] F hap_p2m_ga_to_gfn_2_levels+0x112/0x25b
(XEN) [<ffff82d0402edd22>] F hap_gva_to_gfn_2_levels+0x1c/0x1e
(XEN) [<ffff82d0402f832e>] F paging_gva_to_gfn+0x14a/0x167
Having this modifier saves converting between hex values from the
backtrace log and offsets in gdb disass output.
gdb/ChangeLog:
2020-09-25 Fam Zheng <famzheng@amazon.com>
* NEWS: Mention the /x modifier of disass.
* cli/cli-cmds.c (disassemble_current_function): Add usage text
for /x modifier.
(disassemble_command): Parse /x modifier for disass.
* disasm.c (gdb_pretty_print_disassembler::pretty_print_insn):
Handle /x modifier.
* disasm.h (enum gdb_disassembly_flag): Add a new flag for /x
modifier.
* record.c (get_insn_history_modifiers): Parse /x modifier.
---
gdb/NEWS | 3 +++
gdb/cli/cli-cmds.c | 17 ++++++++++++-----
gdb/disasm.c | 5 ++++-
gdb/disasm.h | 1 +
gdb/record.c | 3 +++
5 files changed, 23 insertions(+), 6 deletions(-)
diff --git a/gdb/NEWS b/gdb/NEWS
index f30d718331..ba1cf76b36 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,9 @@
*** Changes since GDB 10
+* A new modifier '/x' is added to disassemble command, to print instruction
+ offsets in hex.
+
* MI changes
** '-break-insert --qualified' and '-dprintf-insert --qualified'
diff --git a/gdb/cli/cli-cmds.c b/gdb/cli/cli-cmds.c
index e3965fea07..e10544a734 100644
--- a/gdb/cli/cli-cmds.c
+++ b/gdb/cli/cli-cmds.c
@@ -1456,12 +1456,12 @@ disassemble_current_function (gdb_disassembly_flags flags)
/* Dump a specified section of assembly code.
Usage:
- disassemble [/mrs]
+ disassemble [/mrsx]
- dump the assembly code for the function of the current pc
- disassemble [/mrs] addr
+ disassemble [/mrsx] addr
- dump the assembly code for the function at ADDR
- disassemble [/mrs] low,high
- disassemble [/mrs] low,+length
+ disassemble [/mrsx] low,high
+ disassemble [/mrsx] low,+length
- dump the assembly code in the range [LOW,HIGH), or [LOW,LOW+length)
A /m modifier will include source code with the assembly in a
@@ -1472,6 +1472,8 @@ disassemble_current_function (gdb_disassembly_flags flags)
A /r modifier will include raw instructions in hex with the assembly.
+ A /x modifier will print offsets in hex.
+
A /s modifier will include source code with the assembly, like /m, with
two important differences:
1) The output is still in pc address order.
@@ -1510,6 +1512,9 @@ disassemble_command (const char *arg, int from_tty)
case 'r':
flags |= DISASSEMBLY_RAW_INSN;
break;
+ case 'x':
+ flags |= DISASSEMBLY_HEX_OFFSET;
+ break;
case 's':
flags |= DISASSEMBLY_SOURCE;
break;
@@ -2535,7 +2540,7 @@ can be shown using \"show listsize\"."));
c = add_com ("disassemble", class_vars, disassemble_command, _("\
Disassemble a specified section of memory.\n\
-Usage: disassemble[/m|/r|/s] START [, END]\n\
+Usage: disassemble[/m|/r|/s|/x] START [, END]\n\
Default is the function surrounding the pc of the selected frame.\n\
\n\
With a /s modifier, source lines are included (if available).\n\
@@ -2551,6 +2556,8 @@ in favor of /s.\n\
\n\
With a /r modifier, raw instructions in hex are included.\n\
\n\
+With a /x modifier, offsets are printed in hex.\n\
+\n\
With a single argument, the function surrounding that address is dumped.\n\
Two arguments (separated by a comma) are taken as a range of memory to dump,\n\
in the form of \"start,end\", or \"start,+length\".\n\
diff --git a/gdb/disasm.c b/gdb/disasm.c
index e45c840068..c681d8b1e9 100644
--- a/gdb/disasm.c
+++ b/gdb/disasm.c
@@ -250,7 +250,10 @@ gdb_pretty_print_disassembler::pretty_print_insn (const struct disasm_insn *insn
the offset takes the place of the "+" here. */
if (offset >= 0)
m_uiout->text ("+");
- m_uiout->field_signed ("offset", offset);
+ m_uiout->field_fmt ("offset",
+ ((flags & DISASSEMBLY_HEX_OFFSET) != 0
+ ? "0x%x" : "%d"),
+ offset);
m_uiout->text (">:\t");
}
else
diff --git a/gdb/disasm.h b/gdb/disasm.h
index b0f535eaa2..fb293650de 100644
--- a/gdb/disasm.h
+++ b/gdb/disasm.h
@@ -31,6 +31,7 @@ enum gdb_disassembly_flag
DISASSEMBLY_OMIT_PC = (0x1 << 4),
DISASSEMBLY_SOURCE = (0x1 << 5),
DISASSEMBLY_SPECULATIVE = (0x1 << 6),
+ DISASSEMBLY_HEX_OFFSET = (0x1 << 7),
};
DEF_ENUM_FLAGS_TYPE (enum gdb_disassembly_flag, gdb_disassembly_flags);
diff --git a/gdb/record.c b/gdb/record.c
index 759395d5bc..44591e8cf0 100644
--- a/gdb/record.c
+++ b/gdb/record.c
@@ -494,6 +494,9 @@ get_insn_history_modifiers (const char **arg)
case 'r':
modifiers |= DISASSEMBLY_RAW_INSN;
break;
+ case 'x':
+ modifiers |= DISASSEMBLY_HEX_OFFSET;
+ break;
case 'f':
modifiers |= DISASSEMBLY_OMIT_FNAME;
break;
--
2.25.1
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