This patch does some basic cleanups on the SystemTap SDT probes API. It
removes spurious newlines, brackets, reindents some code, and do
explicit checks for NULL, NUL, and 0 where applicable.
2013-12-23 Sergio Durigan JUnior <sergiodj@redhat.com>
* stap-probe.c (struct stap_probe) <args_parsed>: Add comment.
(stap_is_generic_prefix): Delete extra brackets. Reindent.
(stap_parse_register_operand): Remove spurious newlines. Simplify
code to parse special token.
(stap_parse_argument_conditionally): Add gdb_assert.
(stap_parse_argument_1): Likewise. Explicitly check for NULL and
NUL.
(stap_parse_probe_arguments): Likewise.
(handle_stap_probe): Likewise. Reindent code.
(get_stap_base_address): Explicitly check for NULL.
(stap_get_probes): Likewise. Reindent code.
(stap_relocate): Explicitly check for 0.
(stap_gen_info_probes_table_values): Likewise.
This patch extends the current generic parser for SystemTap SDT probe
arguments. It can be almost considered a cleanup, but the main point of
it is actually to allow the generic parser to accept multiple prefixes
and suffixes for the its operands (i.e., integers, register names, and
register indirection).
I have chosen to implement this as a list of const strings, and declare
this list as "static" inside each target's method used to initialize
gdbarch.
This patch is actually a preparation for an upcoming patch for ARM,
which implements the support for multiple integer prefixes (as defined
by ARM's asm spec). And AArch64 will also need this, for the same
reason.
This patch was regtested on all architectures that it touches (i.e.,
i386, x86_64, ARM, PPC/PPC64, s390x and IA-64). No regressions were found.
2013-12-19 Sergio Durigan Junior <sergiodj@redhat.com>
* amd64-tdep.c (amd64_init_abi): Declare SystemTap SDT probe
argument prefixes and suffixes. Initialize gdbarch with them.
* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh (stap_integer_prefix, stap_integer_suffix)
(stap_register_prefix, stap_register_suffix)
(stap_register_indirection_prefix)
(stap_register_indirection_suffix): Declare as "const char *const
*" instead of "const char *". Adjust printing function. Rename
all of the variables to the plural.
(pstring_list): New function.
* i386-tdep.c (i386_elf_init_abi): Declare SystemTap SDT probe
argument prefixes and suffixes. Initialize gdbarch with them.
* ia64-linux-tdep.c (ia64_linux_init_abi): Likewise.
* ppc-linux-tdep.c (ppc_linux_init_abi): Likewise.
* s390-linux-tdep.c (s390_gdbarch_init): Likewise.
* stap-probe.c (stap_is_generic_prefix): New function.
(stap_is_register_prefix): Likewise.
(stap_is_register_indirection_prefix): Likewise.
(stap_is_integer_prefix): Likewise.
(stap_generic_check_suffix): Likewise.
(stap_check_integer_suffix): Likewise.
(stap_check_register_suffix): Likewise.
(stap_check_register_indirection_suffix): Likewise.
(stap_parse_register_operand): Remove unecessary declarations for
variables holding prefix and suffix information. Use the new
functions listed above for checking for prefixes and suffixes.
(stap_parse_single_operand): Likewise.
This patch sanitizes the access to gdbarch made by various functions of
the SDT probe API. Before this patch, gdbarch was being accessed via
the probe's objfile; however, this proved to cause a bug on 32-bit ARM
targets because during the parsing of the probe's arguments the code
needed to access some pseudo-registers of the architecture, and this
information is not fully correct on the objfile's gdbarch.
Basically, the approach taken was to instead pass the current/selected
frame to the parsing and evaluation functions, so that they can extract
the gdbarch directly from the frame. It solved the ARM bug reported
above, and also contributed to make the API cleaner.
Tested on x86_64 and 32-bit ARM.
2013-12-11 Sergio Durigan Junior <sergiodj@redhat.com>
* break-catch-throw.c (fetch_probe_arguments): Pass selected frame
to get_probe_argument_count and evaluate_probe_argument.
* probe.c (get_probe_argument_count): Adjust declaration to accept
frame. Pass frame to probe_ops's get_probe_argument_count.
(evaluate_probe_argument): Likewise, for evaluate_probe_argument.
(probe_safe_evaluate_at_pc): Pass frame to
get_probe_argument_count and evaluate_probe_argument.
* probe.h (struct probe_ops) <get_probe_argument_count,
evaluate_probe_argument>: Adjust declarations to accept frame.
(get_probe_argument_count, evaluate_probe_argument): Likewise.
* solib-svr4.c (solib_event_probe_action): Get current frame.
Pass it to get_probe_argument_count.
(svr4_handle_solib_event): Get current frame. Pass it to
get_probe_argument_count and evaluate_probe_argument.
* stap-probe.c (stap_parse_probe_arguments): Adjust declaration to
accept gdbarch. Do not obtain it from the probe's objfile.
(stap_get_probe_argument_count): Adjust declaration to accept
frame. Obtain gdbarch from the frame. Call generic
can_evaluate_probe_arguments. Pass gdbarch to
stap_parse_probe_arguments.
(stap_get_arg): Adjust declaration to accept gdbarch. Pass it to
stap_parse_probe_arguments.
(stap_evaluate_probe_argument): Adjust declaration to accept
frame. Obtain gdbarch from the frame. Pass gdbarch to
stap_get_arg.
(stap_compile_to_ax): Pass agent_expr's gdbarch to stap_get_arg.
(compute_probe_arg): Obtain gdbarch from frame. Pass frame to
get_probe_argument_count and evaluate_probe_argument.
While looking into the probe API, it seemed to me that there were a
number of methods in sym_probe_fns that were not needed. This patch
removes them.
Specifically, it seems to me that sym_probe_fns ought to be concerned
with the API for constructing the probes. Any method relating to some
aspect of an individual probe can be handled via the probe's own
vtable. That is, the double indirection here doesn't seem useful --
it certainly isn't in fact used, but also I couldn't think of a
potential use.
2013-12-06 Tom Tromey <tromey@redhat.com>
* break-catch-throw.c (fetch_probe_arguments): Use
get_probe_argument_count and evaluate_probe_argument.
* elfread.c (elf_get_probe_argument_count)
(elf_can_evaluate_probe_arguments, elf_evaluate_probe_argument)
(elf_compile_to_ax): Remove.
(elf_probe_fns): Update.
* probe.c (get_probe_argument_count, can_evaluate_probe_arguments)
(evaluate_probe_argument): Call method on probe, not via sym
functions.
* stap-probe.c (compute_probe_arg): Use get_probe_argument_count,
evaluate_probe_argument.
(compile_probe_arg): Use get_probe_argument_count. Call method on
probe, not via sym functions.
* symfile-debug.c (debug_sym_get_probe_argument_count)
(debug_can_evaluate_probe_arguments)
(debug_sym_evaluate_probe_argument, debug_sym_compile_to_ax):
Remove.
(debug_sym_probe_fns): Remove.
* symfile.h (struct sym_probe_fns) <sym_get_probe_argument_count,
can_evaluate_probe_arguments, sym_evaluate_probe_argument,
sym_compile_to_ax>: Remove fields.
This moves the "gdbarch" field from the objfile into the BFD.
This field's value is derived from the BFD and is immutable over the
lifetime of the BFD. This makes it a reasonable candidate for pushing
into the per-BFD object.
This is part of the long-term objfile splitting project. In the long
run I think this patch will make it simpler to moves types from the
objfile to the per-BFD object; but the patch makes sense as a minor
cleanup by itself.
Built and regtested on x86-64 Fedora 18.
* cp-namespace.c (cp_lookup_symbol_imports_or_template): Use
get_objfile_arch.
* elfread.c (elf_rel_plt_read, elf_gnu_ifunc_record_cache)
(elf_gnu_ifunc_resolve_by_got): Use get_objfile_arch.
* jit.c (jit_object_close_impl): Update.
* jv-lang.c (get_dynamics_objfile): Update.
* linespec.c (add_minsym): Use get_dynamics_objfile.
* objfiles.c (get_objfile_bfd_data): Initialize 'gdbarch' field.
(allocate_objfile): Don't initialize 'gdbarch' field.
(get_objfile_arch): Update.
* objfiles.h (struct objfile_per_bfd_storage) <gdbarch>: New field,
moved from...
(struct objfile) <gdbarch>: ... here. Remove.
* stap-probe.c (stap_can_evaluate_probe_arguments): Use
get_objfile_arch.
* symfile.c (init_entry_point_info): Use get_objfile_arch.
* breakpoint.c (create_longjmp_master_breakpoint): Check if probe
interface can evaluate arguments. Fallback to the old mode if it
cannot.
(create_exception_master_breakpoint): Likewise.
* elfread.c (elf_can_evaluate_probe_arguments): New function.
(struct sym_probe_fns elf_probe_fns): Export function above to the
probe interface.
* probe.c (can_evaluate_probe_arguments): New function.
* probe.h (struct probe_ops) <can_evaluate_probe_arguments>: New
function pointer.
(can_evaluate_probe_arguments): New function prototype.
* solib-svr4.c (svr4_create_solib_event_breakpoints): Check if
probe interface can evaluate arguments. Fallback to the old mode
if it cannot.
* stap-probe.c (stap_get_probe_argument_count): Check if probe
interface can evaluate arguments. Warning the user if it cannot.
(stap_can_evaluate_probe_arguments): New function.
(struct probe_ops stap_probe_ops): Export function above to the
probe interface.
* symfile.h (struct sym_probe_fns) <can_evaluate_probe_arguments>:
New function pointer.
As a follow up to:
http://sourceware.org/ml/gdb-patches/2013-03/msg00449.html
In a nutshell, casts between 'char **' <-> 'unsigned char **' and
'char **' <-> 'const char **' are invalid.
I grepped for "\*\*) &" and found these. There's another one in
demangle.c, but I've split fixing that one to a separate patch.
I think the ada_decode_symbol change is perhaps the one that could be
surprising. The function's description has this comment, which makes
things much clearer:
The GSYMBOL parameter is "mutable" in the C++ sense: logically
const, but nevertheless modified to a semantically equivalent form
when a decoded name is cached in it. */
const char *
ada_decode_symbol (const struct general_symbol_info *gsymbol)
With that out of the way, I think the patch ends up being pretty
obvious.
Tested on x86_64 Fedora 17.
gdb/
2013-03-13 Pedro Alves <palves@redhat.com>
* ada-lang.c (ada_decode_symbol): Cast away constness of GSYMBOL
rather than casting 'const char * const *' to 'const char **'.
* ada-lex.l (processInt): Make "trailer" local const. Remove
'const char **' cast.
* arm-linux-tdep.c (arm_stap_parse_special_token): Add 'char *'
locals, and use those as strtol output pointer, instead than doing
invalid casts to from 'const char **' to 'char **'.
(_initialize_demangle): Remove cast.
* i386-tdep.c (i386_stap_parse_special_token): : Add 'char *'
locals, and use those as strtol output pointer, instead than doing
invalid casts to from 'const char **' to 'char **'.
* solib-dsbt.c (dsbt_get_initial_loadmaps): Remove 'gdb_byte**'
casts.
* stap-probe.c (stap_parse_register_operand)
(stap_parse_single_operand): Likewise.
$ make WERROR_CFLAGS="-Wpointer-sign -Werror" stap-probe.o 2>&1 1>/dev/null
../../src/gdb/stap-probe.c: In function ‘handle_stap_probe’:
../../src/gdb/stap-probe.c:1306:19: error: pointer targets in assignment differ in signedness [-Werror=pointer-sign]
cc1: all warnings being treated as errors
make: *** [stap-probe.o] Error 1
provider is a string, so it's rightfully a char*. 'data' holds raw
bytes (bfd_byte), so a cast is the right thing to do.
gdb/
2013-03-07 Pedro Alves <palves@redhat.com>
* stap-probe.c (handle_stap_probe): Add cast to char*.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
