Commit Graph

25108 Commits

Author SHA1 Message Date
John Baldwin
325c9fd4aa Don't throw an error in 'info registers' for unavailable MIPS registers.
'info registers' for MIPS throws an error and when it first encounters
an unavailable register.  This does not match other architectures
which annotate unavailable registers and continue to print out the
values of subsequent registers.  Replace the error by displaying an
aligned "<unavailable>".  This string is truncated to "<unavl>" when
displaying a 32-bit register.

gdb/ChangeLog:

	* mips-tdep.c (print_gp_register_row): Don't error for unavailable
	registers.
2017-06-19 14:40:22 -07:00
Pedro Alves
16b7a71998 .gdb_index writer: close the file before unlinking it
We should close the file before unlinking because on MS-Windows one
cannot delete a file that is still open.

I considered making 'gdb::unlinker::unlinker(const char *)'
'noexcept(true)' and then adding
  static_assert (noexcept (gdb::unlinker (filename.c_str ())), "");

but that doesn't really work because gdb::unlinker has a gdb_assert,
which can throw a QUIT if/when the assertion fails.  'noexcept(true)'
would cause GDB to abruptly terminate if/when the assertion fails.

gdb/ChangeLog:
2017-06-19  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (write_psymtabs_to_index): Construct file_closer
	after gdb::unlinker.
2017-06-19 12:46:47 +01:00
Sergio Durigan Junior
1c8e01c960 Use getenv instead of gdb_environ on mi-cmd-env.c
This is a spinoff of
<https://sourceware.org/ml/gdb-patches/2017-06/msg00437.html>.
mi-cmd-env.c is using the whole gdb_environ machinery in order to
access just one variable, which can be easily replaced by a simple
call to getenv.  This patch does that, and doesn't cause regressions.

gdb/ChangeLog:
2017-06-18  Sergio Durigan Junior  <sergiodj@redhat.com>

	* mi/mi-cm-env.c (_initialize_mi_cmd_env): Use getenv instead of
	gdb_environ to access an environment variable.
2017-06-19 00:14:00 -04:00
Thomas Petazzoni
ffce45d224 nat/linux-ptrace.c: add missing gdb_byte* cast
On noMMU platforms, the following code gets compiled:

  child_stack = xmalloc (STACK_SIZE * 4);

Where child_stack is a gdb_byte*, and xmalloc() returns a void*. While
the lack of cast is valid in C, it is not in C++, causing the
following build failure:

../nat/linux-ptrace.c: In function 'int linux_fork_to_function(gdb_byte*, int (*)(void*))':
../nat/linux-ptrace.c:273:29: error: invalid conversion from 'void*' to 'gdb_byte* {aka unsigned char*}' [-fpermissive]
       child_stack = xmalloc (STACK_SIZE * 4);

Therefore, this commit adds the appropriate cast.

gdb/ChangeLog:

	* nat/linux-ptrace.c (linux_fork_to_function): Add cast to
	gdb_byte*.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2017-06-18 23:29:03 +02:00
Simon Marchi
1d4fbac99e Add ATTRIBUTE_PRINTF to trace_start_error
clang complains that the fmt passed to vwarning in trace_start_error is
not a literal.  This looks like a fair warning, which can be removed by
adding ATTRIBUTE_PRINTF to the declaration of trace_start_error.

gdb/ChangeLog:

	* nat/fork-inferior.h (trace_start_error): Add ATTRIBUTE_PRINTF.
2017-06-17 23:19:25 +02:00
Simon Marchi
8465943af6 gdb: Add -Wno-mismatched-tags
clang complains that for some types, we use both the class and struct
keywords in different places.  It's not really a problem, so I think we
can safely turn this warning off.

gdb/ChangeLog:

	* configure: Re-generate.
	* warning.m4 (build_warnings): Add -Wno-mismatched-tags.

gdb/gdbserver/ChangeLog:

	* configure: Re-generate.
2017-06-17 23:18:49 +02:00
Simon Marchi
3e019bdc20 gdb: Use -Werror when checking for (un)supported warning flags
In warning.m4, we pass all the warning flags one by one to the compiler
to test if they are supported by this particular compiler.  If the
compiler exits with an error, we conclude that this warning flag is not
supported and exclude it.  This allows us to use warning flags without
having to worry about which versions of which compilers support each
flag.

clang, by default, only emits a warning if an unknown flag is passed:

  warning: unknown warning option '-Wfoo' [-Wunknown-warning-option]

The result is that we think that all the warning flags we use are
supported by clang (they are not), and the compilation fails later when
building with -Werror, since the aforementioned warning becomes an
error.  The fix is to also pass -Werror when probing for supported
flags, then we'll correctly get an error when using an unknown warning,
and we'll exclude it:

  error: unknown warning option '-Wfoo' [-Werror,-Wunknown-warning-option]

I am not sure why there is a change in a random comment in
gdbserver/configure, but I suppose it's a leftfover from a previous
patch, so I included it.

gdb/ChangeLog:

	* configure: Re-generate.
	* warning.m4: Pass -Werror to compiler when checking for
	supported warning flags.

gdb/gdbserver/ChangeLog:

	* configure: Re-generate.
2017-06-17 23:18:20 +02:00
Simon Marchi
cf0dd6f02c gdb: Pass -x c++ to the compiler
Because we are compiling .c files containing C++ code, clang++ complains
with:

  clang: error: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated

If renaming all the source files to .cpp is out of the question, an
alternative is to pass "-x c++" to convince the compiler that we are
really compiling C++.  It works fine with GCC too.

gdb/ChangeLog:

	* Makefile.in (COMPILE.pre): Add "-x c++".

gdb/gdbserver/ChangeLog:

	* Makefile.in (COMPILE.pre): Add "-x c++".
2017-06-17 23:17:00 +02:00
Yao Qi
6f98355cda extract/store integer function template
This patch converts functions extract_{unsigned,signed}_integer
to a function template extract_integer, which has two instantiations.  It
also does the similar changes to store__{unsigned,signed}_integer,
regcache::raw_read_{unsigned,signed}, regcache::raw_write_{unsigned,signed},
regcache::cooked_read_{unsigned,signed},
regcache::cooked_write_{unsigned,signed}.

This patch was posted here
https://sourceware.org/ml/gdb-patches/2017-05/msg00492.html but the
problem was fixed in a different way.  However, I think the patch is still
useful to shorten the code.

gdb:

2017-06-16  Alan Hayward  <alan.hayward@arm.com>
	    Pedro Alves  <palves@redhat.com>
	    Yao Qi  <yao.qi@linaro.org>

	* defs.h (RequireLongest): New.
	(extract_integer): Declare function template.
	(extract_signed_integer): Remove the declaration, but define it
	static inline.
	(extract_unsigned_integer): Likewise.
	(store_integer): Declare function template.
	(store_signed_integer): Remove the declaration, but define it
	static inline.
	(store_unsigned_integer): Likewise.
	* findvar.c (extract_integer): New function template.
	(extract_signed_integer): Remove.
	(extract_unsigned_integer): Remove.
	(extract_integer<LONGEST>, extract_integer<ULONGEST>): Explicit
	instantiations.
	(store_integer): New function template.
	(store_signed_integer): Remove.
	(store_unsigned_integer): Remove.
	(store_integer): Explicit instantiations.
	* regcache.c (regcache_raw_read_signed): Update.
	(regcache::raw_read): New function.
	(regcache::raw_read_signed): Remove.
	(regcache::raw_read_unsigned): Remove.
	(regcache_raw_read_unsigned): Update.
	(regcache_raw_write_unsigned): Update.
	(regcache::raw_write_signed): Remove.
	(regcache::raw_write): New function.
	(regcache_cooked_read_signed): Update.
	(regcache::raw_write_unsigned): Remove.
	(regcache::cooked_read_signed): Remove.
	(regcache_cooked_read_unsigned): Update.
	(regcache::cooked_read_unsigned): Remove.
	(regcache_cooked_write_signed): Update.
	(regcache_cooked_write_unsigned): Update.
	* regcache.h (regcache) <raw_read_signed>: Remove.
	<raw_write_signed, raw_read_unsigned, raw_write_unsigned>: Remove.
	<raw_read, raw_write>: New.
	<cooked_read_signed, cooked_write_signed>: Remove.
	<cooked_write_unsigned, cooked_read_unsigned>: Remove.
	<cooked_read, cooked_write>: New.
	* sh64-tdep.c (sh64_pseudo_register_read): Update.
	(sh64_pseudo_register_write): Update.
2017-06-16 15:38:42 +01:00
Anton Kolesov
a87dc45adc arc: Select CPU model properly before disassembling
Enforce CPU model for disassembler via its options, if it was specified in XML
target description, otherwise use default method of determining CPU implemented
in disassembler - scanning ELF private header.  The latter requires
disassemble_info->section to be properly initialized.  To make sure that
info->section is set in all cases this patch partially reverts [1] for ARC: it
reinstates arc_delayed_print_insn as a "print_insn" function for ARC, but
now this function only sets disassemble_info->section and then calls
default_print_insn to do the rest of the job.

Support for CPU in disassembler options for ARC has been added in [2].

[1] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=39503f82427e22ed8e04d986ccdc8562091ec62e
[2] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=10045478d984f9924cb945423388ba25b7dd3ffe

gdb/ChangeLog:

yyyy-mm-dd  Anton Kolesov  <anton.kolesov@synopsys.com>

	* arc-tdep.c (arc_disassembler_options): New variable.
	(arc_gdbarch_init): Set and use it. Use arc_delayed_print_insn instead
	of default_print_insn.
	(arc_delayed_print_insn): Set info->section when needed,
	use default_print_insn to retrieve a disassembler.
2017-06-16 14:54:17 +03:00
Sergio Durigan Junior
45159d6ad3 PR gdb/21574: Mention $SHELL and startup-with-shell on "help run"
This simple patch updates the documentation of "help run" in order to
mention that the shell used to start the inferior comes from the
$SHELL environment variable.  It also mentions that this behaviour can
be disabled by using the "set startup-with-shell off" command.

gdb/ChangeLog:
2017-06-14  Sergio Durigan Junior  <sergiodj@redhat.com>

	PR gdb/21574
	* infcmd.c (_initialize_infcmd): Expand "help run" documentation
	to mention $SHELL and startup-with-shell.
2017-06-14 22:44:01 -04:00
Max Filippov
b46c4cf090 Maxim Grigoriev stepping down as Xtensa maintainer
gdb/
2017-06-14  Max Filippov  <jcmvbkbc@gmail.com>

	* MAINTAINERS: Move Maxim Grigoriev to the Past Maintainers.
2017-06-14 10:45:03 -07:00
Yao Qi
6394c60699 Don't use print_insn_XXX in GDB
This is a follow-up to

  [PATCH 0/6] Unify the disassembler selection in gdb and objdump
  https://sourceware.org/ml/binutils/2017-05/msg00192.html

that is, opcodes is able to select the right disassembler, so gdb
doesn't have to select them.  Instead, gdb can just use
default_print_insn.  As a result, these print_insn_XXX are not used
out of opcodes, so this patch also moves their declarations from
include/dis-asm.h to opcodes/disassemble.h.  With this change,
GDB doesn't use any print_insn_XXX directly any more.

gdb:

2017-06-14  Yao Qi  <yao.qi@linaro.org>

	* aarch64-tdep.c (aarch64_gdb_print_insn): Call
	default_print_insn instead of print_insn_aarch64.
	* arm-tdep.c (gdb_print_insn_arm): Call
	default_print_insn instead of print_insn_big_arm
	and print_insn_little_arm.
	* i386-tdep.c (i386_print_insn): Call default_print_insn
	instead of print_insn_i386.
	* ia64-tdep.c (ia64_print_insn): Call
	default_print_insn instead of print_insn_ia64.
	* mips-tdep.c (gdb_print_insn_mips): Call
	default_print_insn instead of print_insn_big_mips
	and print_insn_little_mips.
	* spu-tdep.c (gdb_print_insn_spu): Call default_print_insn
	instead of print_insn_spu.

include:

2017-06-14  Yao Qi  <yao.qi@linaro.org>

	* dis-asm.h (print_insn_aarch64): Move it to opcodes/disassemble.h.
	(print_insn_big_arm, print_insn_big_mips): Likewise.
	(print_insn_i386, print_insn_ia64): Likewise.
	(print_insn_little_arm, print_insn_little_mips): Likewise.
	(print_insn_spu): Likewise.

opcodes:

2017-06-14  Yao Qi  <yao.qi@linaro.org>

	* aarch64-dis.c: Include disassemble.h instead of dis-asm.h.
	* arm-dis.c: Likewise.
	* ia64-dis.c: Likewise.
	* mips-dis.c: Likewise.
	* spu-dis.c: Likewise.
	* disassemble.h (print_insn_aarch64): New declaration, moved from
	include/dis-asm.h.
	(print_insn_big_arm, print_insn_big_mips): Likewise.
	(print_insn_i386, print_insn_ia64): Likewise.
	(print_insn_little_arm, print_insn_little_mips): Likewise.
2017-06-14 16:29:01 +01:00
Pedro Alves
d5722aa2fe Introduce gdb::byte_vector, add allocator that default-initializes
In some cases we've been replacing heap-allocated gdb_byte buffers
managed with xmalloc/make_cleanup(xfree) with gdb::vector<gdb_byte>.
That usually pessimizes the code a little bit because std::vector
value-initializes elements (which for gdb_byte means
zero-initialization), while if you're creating a temporary buffer,
you're most certaintly going to fill it in with some data.  An
alternative is to use

  unique_ptr<gdb_byte[]> buf (new gdb_byte[size]);

but it looks like that's not very popular.

Recently, a use of obstacks in dwarf2read.c was replaced with
std::vector<gdb_byte> and that as well introduced a pessimization for
always memsetting the buffer when it's garanteed that the zeros will
be overwritten immediately.  (see dwarf2read.c change in this patch to
find it.)

So here's a different take at addressing this issue "by design":

#1 - Introduce default_init_allocator<T>

I.e., a custom allocator that does default construction using default
initialization, meaning, no more zero initialization.  That's the
default_init_allocation<T> class added in this patch.

See "Notes" at
<http://en.cppreference.com/w/cpp/container/vector/resize>.

#2 - Introduce def_vector<T>

I.e., a convenience typedef, because typing the allocator is annoying:

  using def_vector<T> = std::vector<T, gdb::default_init_allocator<T>>;

#3 - Introduce byte_vector

Because gdb_byte vectors will be the common thing, add a convenience
"byte_vector" typedef:

  using byte_vector = def_vector<gdb_byte>;

which is really the same as:

  std::vector<gdb_byte, gdb::default_init_allocator<gdb_byte>>;

The intent then is to make "gdb::byte_vector" be the go-to for dynamic
byte buffers.  So the less friction, the better.

#4 - Adjust current code to use it.

To set the example going forward.  Replace std::vector uses and also
unique_ptr<byte[]> uses.

One nice thing is that with this allocator, for changes like these:

  -std::unique_ptr<byte[]> buf (new gdb_byte[some_size]);
  +gdb::byte_vector buf (some_size);
   fill_with_data (buf.data (), buf.size ());

the generated code is the same as before.  I.e., the compiler
de-structures the vector and gets rid of the unused "reserved vs size"
related fields.

The other nice thing is that it's easier to write
  gdb::byte_vector buf (size);
than
  std::unique_ptr<gdb_byte[]> buf (new gdb_byte[size]);
or even (C++14):
  auto buf = std::make_unique<gdb_byte[]> (size); // zero-initializes...

#5 - Suggest s/std::vector<gdb_byte>/gdb::byte_vector/ going forward.

Note that this commit actually fixes a couple of bugs where the current
code is incorrectly using "std::vector::reserve(new_size)" and then
accessing the vector's internal buffer beyond the vector's size: see
dwarf2loc.c and charset.c.  That's undefined behavior and may trigger
debug mode assertion failures.  With default_init_allocator,
"resize()" behaves like "reserve()" performance wise, in that it
leaves new elements with unspecified values, but, it does that safely
without triggering undefined behavior when you access those values.

gdb/ChangeLog:
2017-06-14  Pedro Alves  <palves@redhat.com>

	* ada-lang.c: Include "common/byte-vector.h".
	(ada_value_primitive_packed_val): Use gdb::byte_vector.
	* charset.c (wchar_iterator::iterate): Resize the vector instead
	of reserving it.
	* common/byte-vector.h: Include "common/def-vector.h".
	(wchar_iterator::m_out): Now a gdb::def_vector<gdb_wchar_t>.
	* cli/cli-dump.c: Include "common/byte-vector.h".
	(dump_memory_to_file, restore_binary_file): Use gdb::byte_vector.
	* common/byte-vector.h: New file.
	* common/def-vector.h: New file.
	* common/default-init-alloc.h: New file.
	* dwarf2loc.c: Include "common/byte-vector.h".
	(rw_pieced_value): Use gdb::byte_vector, and resize the vector
	instead of reserving it.
	* dwarf2read.c: Include "common/byte-vector.h".
	(data_buf::m_vec): Now a gdb::byte_vector.
	* gdb_regex.c: Include "common/def-vector.h".
	(compiled_regex::compiled_regex): Use gdb::def_vector<char>.
	* mi/mi-main.c: Include "common/byte-vector.h".
	(mi_cmd_data_read_memory): Use gdb::byte_vector.
	* printcmd.c: Include "common/byte-vector.h".
	(print_scalar_formatted): Use gdb::byte_vector.
	* valprint.c: Include "common/byte-vector.h".
	(maybe_negate_by_bytes, print_decimal_chars): Use
	gdb::byte_vector.
2017-06-14 11:08:52 +01:00
Simon Marchi
01ec7a2722 darwin-nat: Add missing include
I forgot this one, which is kind of related.

The function trace_start_error_with_name has moved in commit "Share
fork_inferior et al with gdbserver", so this additional include is
needed.

Fixes:

darwin-nat.c:1735:5: error: use of undeclared identifier 'trace_start_error_with_name'
    trace_start_error_with_name ("close");

gdb/ChangeLog:

	* darwin-nat.c: Include "nat/fork-inferior.h".
2017-06-13 21:14:50 +02:00
Simon Marchi
848d907446 darwin: Add fork-inferior.o to NATDEPFILES
I happened to be build-testing on macOS and found this:

  Undefined symbols for architecture x86_64:

    "fork_inferior(char const*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, char**, void (*)(), void (*)(int), void (*)(), char const*, void (*)(char const*, char* const*, char* const*))", referenced from:

        darwin_create_inferior(target_ops*, char const*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, char**, int) in darwin-nat.o

    "startup_inferior(int, int, target_waitstatus*, ptid_t*)", referenced from:

        gdb_startup_inferior(int, int) in fork-child.o

    "trace_start_error(char const*, ...)", referenced from:

        darwin_ptrace_me() in darwin-nat.o

    "trace_start_error_with_name(char const*)", referenced from:

        darwin_ptrace_me() in darwin-nat.o

  ld: symbol(s) not found for architecture x86_64

  clang: error: linker command failed with exit code 1 (use -v to see invocation)

Adding fork-inferior.o fixes it.  I factored out the Darwin bits that
are no architecture-specific in the section meant for that at the top.

I only built-tested this using Travis-CI, since I don't have access to
this platform.

gdb/ChangeLog:

	* configure.nat: Factor out Darwin bits that are not
	architecture-specific.  Add fork-inferior.o.
2017-06-13 21:14:35 +02:00
Simon Marchi
3b912944f4 aix: Add fork-inferior.o to NATDEPFILES
Trying to build on AIX gives:

ld: 0711-317 ERROR: Undefined symbol: .trace_start_error_with_name(char const*)
ld: 0711-317 ERROR: Undefined symbol: .fork_inferior(char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, char**, void (*)(), void (*)(int), void (*)(), char const*, void (*)(char const*, char* const*, char* const*))
ld: 0711-317 ERROR: Undefined symbol: .startup_inferior(int, int, target_waitstatus*, ptid_t*)

Including fork-inferior.o in the build should help.  I also factored out
the AIX bits that are not architecture-specific to be consistent with the other
OSes.

gdb/ChangeLog:

	* configure.nat: Factor out AIX bits that are not
	architecture-specific.  Add fork-inferior.o.
2017-06-13 21:14:25 +02:00
Andreas Arnez
55acdf2242 read/write_pieced_value: Merge into one function
Since read_pieced_value and write_pieced_value share significant logic,
this patch merges them into a single function rw_pieced_value.

gdb/ChangeLog:

	* dwarf2loc.c (rw_pieced_value): New.  Merge logic from...
	(read_pieced_value, write_pieced_value): ...here.  Reduce to
	wrappers that just call rw_pieced_value.
2017-06-13 15:20:32 +02:00
Andreas Arnez
f65e204425 write_pieced_value: Notify memory_changed observers
So far write_pieced_value uses write_memory when writing memory pieces to
the target.  However, this is a case where GDB potentially overwrites a
watchpoint value.  In such a case write_memory_with_notification should be
used instead, so that memory_changed observers get notified.

gdb/ChangeLog:

	* dwarf2loc.c (write_pieced_value): When writing the data for a
	memory piece, use write_memory_with_notification instead of
	write_memory.
2017-06-13 15:20:32 +02:00
Andreas Arnez
23f945bf8c Fix bit-/byte-offset mismatch in parameter to read_value_memory
The function read_value_memory accepts a parameter embedded_offset and
expects it to represent the byte offset into the given value.  However,
the only invocation with a possibly non-zero embedded_offset happens in
read_pieced_value, where a bit offset is passed instead.

Adjust the implementation of read_value_memory to meet the caller's
expectation.  This implicitly fixes the invocation in read_pieced_value.

gdb/ChangeLog:

	* valops.c (read_value_memory): Change embedded_offset to
	represent a bit offset instead of a byte offset.
	* value.h (read_value_memory): Adjust comment.
2017-06-13 15:20:31 +02:00
Andreas Arnez
f236533e3c read/write_pieced_value: Remove unnecessary variable copies
In read_pieced_value's main loop, the variables `dest_offset_bits' and
`source_offset_bits' are basically just copies of `offset' and
`bits_to_skip', respectively.  In write_pieced_value the copies are
reversed.  This is not very helpful when trying to keep the logic between
these functions in sync.  Since the copies are unnecessary, this patch
just removes them.

gdb/ChangeLog:

	* dwarf2loc.c (read_pieced_value): Remove unnecessary variables
	dest_offset_bits and source_offset_bits.
	(write_pieced_value): Likewise.
2017-06-13 15:20:31 +02:00
Andreas Arnez
65d84b7616 Respect piece offset for DW_OP_bit_piece
So far GDB ignores the piece offset of all kinds of DWARF bit
pieces (DW_OP_bit_piece) and treats such pieces as if the offset was zero.

This is fixed, and an appropriate test is added.

gdb/ChangeLog:

	* dwarf2loc.c (read_pieced_value): Respect the piece offset, as
	given by DW_OP_bit_piece.
	(write_pieced_value): Likewise.

  Andreas Arnez  <arnez@linux.vnet.ibm.com>

	* gdb.dwarf2/var-access.exp: Add test for composite location with
	nonzero piece offsets.
2017-06-13 15:20:31 +02:00
Andreas Arnez
242d31ab7c read/write_pieced_value: Improve logic for buffer allocation
So far the main loop in read_pieced_value and write_pieced_value is
structured like this:

(1) Prepare a buffer and some variables we may need;

(2) depending on the DWARF piece type to be handled, use the buffer and
    the prepared variables, ignore them, or even recalculate them.

This approach reduces readability and may also lead to unnecessary copying
of data.  This patch moves the preparations to the places where sufficient
information is available and removes some of the variables involved.

gdb/ChangeLog:

	* dwarf2loc.c (read_pieced_value): Move the buffer allocation and
	some other preparations to the places where sufficient information
	is available.
	(write_pieced_value): Likewise.
2017-06-13 15:20:30 +02:00
Andreas Arnez
03c8af18d1 Fix handling of DWARF register pieces on big-endian targets
For big-endian targets the logic in read/write_pieced_value tries to take
a register piece from the LSB end.  This requires offsets and sizes to be
adjusted accordingly, and that's where the current implementation has some
issues:

* The formulas for recalculating the bit- and byte-offsets into the
  register are wrong.  They just happen to yield correct results if
  everything is byte-aligned and the piece's last byte belongs to the
  given value.

* After recalculating the bit offset into the register, the number of
  bytes to be copied from the register is not recalculated.  Of course
  this does not matter if everything (particularly the piece size) is
  byte-aligned.

These issues are fixed.  The size calculation is performed with a new
helper function bits_to_bytes().

gdb/ChangeLog:

	* dwarf2loc.c (bits_to_bytes): New function.
	(read_pieced_value): Fix offset calculations for register pieces
	on big-endian targets.
	(write_pieced_value): Likewise.

gdb/testsuite/ChangeLog:

	* gdb.dwarf2/var-access.exp: Add test for non-byte-aligned
	register pieces.
2017-06-13 15:20:30 +02:00
Andreas Arnez
840989c113 read/write_pieced_value: Drop 'buffer_size' variable
When the variable 'buffer_size' in read_pieced_value and
write_pieced_value was introduced, it was needed for tracking the buffer's
allocated size.  Now that the buffer's data type has been changed to a
std::vector, the variable is no longer necessary; so remove it.

gdb/ChangeLog:

	* dwarf2loc.c (read_pieced_value): Remove buffer_size variable.
	(write_pieced_value): Likewise.
2017-06-13 15:20:30 +02:00
Andreas Arnez
359b19bb24 write_pieced_value: Transfer least significant bits into bit-field
On big-endian targets, when targeting a bit-field, write_pieced_value
currently transfers the source value's *most* significant bits to the
target value, instead of its least significant bits.  This is fixed.

In particular the fix adjusts the initial value of 'offset', which can now
potentially be nonzero.  Thus the variable 'type_len' is renamed to
'max_offset', to avoid confusion.  And for consistency, the affected logic
that was mirrored in read_pieced_value is changed there in the same way.

gdb/ChangeLog:

	* dwarf2loc.c (write_pieced_value): When writing to a bit-field,
	transfer the source value's least significant bits, instead of its
	lowest-addressed ones.  Rename type_len to max_offset.
	(read_pieced_value): Mirror above changes to write_pieced_value as
	applicable.
2017-06-13 15:20:28 +02:00
Andreas Arnez
07c9ca3bd8 write_pieced_value: Fix buffer offset for memory pieces
In write_pieced_value, when transferring the data to target memory via a
buffer, the bit offset within the target value is not reduced to its
sub-byte fraction before using it as a bit offset into the buffer.  This
is fixed.

gdb/ChangeLog:

	* dwarf2loc.c (write_pieced_value): In DWARF_VALUE_MEMORY,
	truncate full bytes from dest_offset_bits before using it as an
	offset into the buffer.
2017-06-13 15:20:28 +02:00
Andreas Arnez
f1cc987420 write_pieced_value: Include transfer size in byte-wise check
In write_pieced_value, when checking whether the data can be transferred
byte-wise, the current logic verifies the source- and destination offsets
to be byte-aligned, but not the transfer size.  This is fixed.

gdb/ChangeLog:

	* dwarf2loc.c (write_pieced_value): Include transfer size in
	byte-wise check.
2017-06-13 15:20:27 +02:00
Andreas Arnez
cdaac320fd write_pieced_value: Fix copy/paste error in size calculation
In write_pieced_value, the number of bytes containing a portion of the
bit-field in a given piece is calculated with the wrong starting offset;
thus the result may be off by one.  This bug was probably introduced when
copying this logic from read_pieced_value.  Fix it.

gdb/ChangeLog:

	* dwarf2loc.c (write_pieced_value): Fix copy/paste error in the
	calculation of this_size.
2017-06-13 15:20:27 +02:00
Andreas Arnez
af547a9614 read/write_pieced_value: Respect value parent's offset
In the case of targeting a bit-field, read_pieced_value and
write_pieced_value calculate the number of bits preceding the bit-field
without considering the relative offset of the value's parent.  This is
relevant for a structure variable like this:

  struct s {
      uint64_t foo;
      struct {
	  uint32_t bar;
	  uint32_t bf : 10;  /* <-- target bit-field */
      } baz;
  } s;

In this scenario, if 'val' is a GDB value representing s.baz.bf,
val->parent represents the whole s.baz structure, and the following holds:

  - value_offset (val) == sizeof s.baz.bar == 4
  - value_offset (val->parent) == sizeof s.foo == 8

The current logic would only use value_offset(val), resulting in the wrong
offset into the target value.  This is fixed.

gdb/ChangeLog:

	* dwarf2loc.c (read_pieced_value): Respect parent value's offset
	when targeting a bit-field.
	(write_pieced_value): Likewise.
2017-06-13 15:20:27 +02:00
Andreas Arnez
ddd7882a58 Remove addr_size field from struct piece_closure
The addr_size field in the piece_closure data structure is a relic from
before introducing the typed DWARF stack.  It is obsolete now.  This patch
removes it.

gdb/ChangeLog:

	* dwarf2loc.c (struct piece_closure) <addr_size>: Remove field.
	(allocate_piece_closure): Drop addr_size parameter.
	(dwarf2_evaluate_loc_desc_full): Adjust call to
	allocate_piece_closure.
2017-06-13 15:20:26 +02:00
Andreas Arnez
e93523245b PR gdb/21226: Take DWARF stack value pieces from LSB end
When taking a DW_OP_piece or DW_OP_bit_piece from a DW_OP_stack_value, the
existing logic always takes the piece from the lowest-addressed end, which
is wrong on big-endian targets.  The DWARF standard states that the
"DW_OP_bit_piece operation describes a sequence of bits using the least
significant bits of that value", and this also matches the current logic
in GCC.  For instance, the GCC guality test case pr54970.c fails on s390x
because of this.

This fix adjusts the piece accordingly on big-endian targets.  It is
assumed that:

* DW_OP_piece shall take the piece from the LSB end as well;

* pieces reaching outside the stack value bits are considered undefined,
  and a zero value can be used instead.

gdb/ChangeLog:

	PR gdb/21226
	* dwarf2loc.c (read_pieced_value): Anchor stack value pieces at
	the LSB end, independent of endianness.

gdb/testsuite/ChangeLog:

	PR gdb/21226
	* gdb.dwarf2/nonvar-access.exp: Add checks for verifying that
	stack value pieces are taken from the LSB end.
2017-06-13 15:20:26 +02:00
Andreas Arnez
d5d1163eff write_pieced_value: Fix size capping logic
A field f in a structure composed of DWARF pieces may be located in
multiple pieces, where the first and last of those may contain bits from
other fields as well.  So when writing to f, the beginning of the first
and the end of the last of those pieces may have to be skipped.  But the
logic in write_pieced_value for handling one of those pieces is flawed
when the first and last piece are the same, i.e., f is contained in a
single piece:

  < - - - - - - - - - piece_size - - - - - - - - - ->
  +-------------------------------------------------+
  | skipped_bits |   f_bits   | / / / / / / / / / / |
  +-------------------------------------------------+

The current logic determines the size of the sub-piece to operate on by
limiting the piece size to the bit size of f and then subtracting the
skipped bits:

  min (piece_size, f_bits) - skipped_bits

Instead of:

  min (piece_size - skipped_bits, f_bits)

So the resulting sub-piece size is corrupted, leading to wrong handling of
this piece in write_pieced_value.

Note that the same bug was already found in read_pieced_value and fixed
there (but not in write_pieced_value), see PR 15391.

This patch swaps the calculations, bringing them into the same (correct)
order as in read_pieced_value.

gdb/ChangeLog:

	* dwarf2loc.c (write_pieced_value): Fix order of calculations for
	size capping.

gdb/testsuite/ChangeLog:

	* gdb.dwarf2/var-pieces.exp: Add test case for modifying a
	variable at nonzero offset.
2017-06-13 15:20:26 +02:00
Yao Qi
032bb6eae8 Move initialize_tdesc_mips* calls from mips-linux-nat.c to mips-linux-tdep.c
All target descriptions except mips initialization are called in -tdep.c,
instead of -nat.c, so this patch moves mips target descriptions
initialization to -tdep.c.  Secondly, I want to change the target
descriptions from pre-generated to dynamical creation, so I want to test
that these pre-generated target descriptions equal to these dynamically
created ones.  Move target descriptions initialization to -tdep.c files so
we can test them in any hosts (if they are still -nat.c, we can only test
them on mips-linux host.).

gdb:

2017-06-13  Yao Qi  <yao.qi@linaro.org>

	* mips-linux-nat.c: Move include features/mips*-linux.c to
	mips-linux-tdep.c.
	(_initialize_mips_linux_nat): Move initialize_tdesc_mips* calls
	to mips-linux-tdep.c.
	* mips-linux-tdep.c: Include features/mips*-linux.c
	(_initialize_mips_linux_tdep): Call initialize_tdesc_mips*
	functions.
	* mips-linux-tdep.h (tdesc_mips_linux): Declare.
	(tdesc_mips_dsp_linux, tdesc_mips64_linux): Declare.
	(tdesc_mips64_dsp_linux): Declare.
2017-06-13 09:05:04 +01:00
Tom Tromey
f12f6bad7d Remove val_print_type_code_int
Now that print_scalar_formatted is more capable, there's no need for
val_print_type_code_int.  This patch removes it in favor of
val_print_scalar_formatted.

2017-06-12  Tom Tromey  <tom@tromey.com>

	* valprint.h (val_print_type_code_int): Remove.
	* valprint.c (generic_val_print_int): Always call
	val_print_scalar_formatted.
	(val_print_type_code_int): Remove.
	* printcmd.c (print_scalar_formatted): Handle options->format==0.
	* f-valprint.c (f_val_print): Use val_print_scalar_formatted.
	* c-valprint.c (c_val_print_int): Use val_print_scalar_formatted.
	* ada-valprint.c (ada_val_print_num): Use
	val_print_scalar_formatted.
2017-06-12 15:04:58 -06:00
Tom Tromey
d9109c8080 Simplify print_scalar_formatted
This unifies the two switches in print_scalar_formatted, removing some
now-redundant code.  Now scalar types are never converted to LONGEST,
instead printing is done using print_*_chars, operating on the byte
representation.

ChangeLog
2017-06-12  Tom Tromey  <tom@tromey.com>

	* printcmd.c (print_scalar_formatted): Unify the two switches.
	Don't convert scalars to LONGEST.

2017-06-12  Tom Tromey  <tom@tromey.com>

	* gdb.arch/altivec-regs.exp: Expect decimal results for uint128.
2017-06-12 15:04:57 -06:00
Tom Tromey
4ac0cb1cf0 Let print_decimal_chars handle signed values
This changes print_decimal_chars to handle signed values.

gdb/ChangeLog
2017-06-12  Tom Tromey  <tom@tromey.com>

	PR exp/16225:
	* valprint.h (print_decimal_chars): Update.
	* valprint.c (maybe_negate_by_bytes): New function.
	(print_decimal_chars): Add "is_signed" argument.
	* printcmd.c (print_scalar_formatted): Update.
2017-06-12 15:04:57 -06:00
Tom Tromey
30a254669b Don't always zero pad in print_*_chars
This changes print_octal_chars and print_decimal_chars to never zero
pad, and changes print_binary_chars and print_hex_chars to only
optionally zero-pad, based on a flag.

ChangeLog
2017-06-12  Tom Tromey  <tom@tromey.com>

	PR exp/16225:
	* valprint.h (print_binary_chars, print_hex_chars): Update.
	* valprint.c (val_print_type_code_int): Update.
	(print_binary_chars): Add "zero_pad" argument.
	(emit_octal_digit): New function.
	(print_octal_chars): Don't zero-pad.
	(print_decimal_chars): Likewise.
	(print_hex_chars): Add "zero_pad" argument.
	* sh64-tdep.c (sh64_do_fp_register): Update.
	* regcache.c (regcache::dump): Update.
	* printcmd.c (print_scalar_formatted): Update.
	* infcmd.c (default_print_one_register_info): Update.

2017-06-12  Tom Tromey  <tom@tromey.com>

	PR exp/16225:
	* gdb.reverse/i386-sse-reverse.exp: Update tests.
	* gdb.arch/vsx-regs.exp: Update tests.
	* gdb.arch/s390-vregs.exp (hex128): New proc.
	Update test.
	* gdb.arch/altivec-regs.exp: Update tests.
2017-06-12 15:04:56 -06:00
Pedro Alves
b3464d0316 mips-tdep.c: Remove MAX_REGISTER_SIZE usage
mips_eabi_push_dummy_call is storing the address of a struct in a
buffer that must have the same of the confisued/set ABI register size.
Add a define for the maximum ABI size and use it to size the local
buffer.  Also rename the 'regsize' local to 'abi_regsize' for clarity.

Tested that --enable-targets=all still builds.

gdb/ChangeLog:
2017-06-12  Pedro Alves  <palves@redhat.com>
	    Alan Hayward  <alan.hayward@arm.com>

	* mips-tdep.c (MAX_MIPS_ABI_REGSIZE): New.
	(mips_eabi_push_dummy_call): Rename local 'regsize' to
	'abi_regsize'.  Rename local array 'valbuf' to 'ref_valbuf', and
	use MAX_MIPS_ABI_REGSIZE instead of MAX_REGISTER_SIZE to size it.
	Assert that abi_regsize bytes fit in 'ref_valbuf'.
2017-06-12 19:04:52 +01:00
Pedro Alves
4b76cda993 .gdb_index prod perf regression: mapped_symtab now vector of values
... instead of vector of pointers

There's no real reason for having mapped_symtab::data be a vector of
heap-allocated symtab_index_entries.  symtab_index_entries is not that
large, it's movable, and it's cheap to move.  Making the vector hold
values instead improves cache locality and eliminates many roundtrips
to the heap.

Using the same test as in the previous patch, against the same gdb
inferior, timing improves ~13% further:

  ~6.0s => ~5.2s (average of 5 runs).

Note that before the .gdb_index C++ifycation patch, we were at ~5.7s.
We're now consistenly better than before.

gdb/ChangeLog
2017-06-12  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (mapped_symtab::data): Now a vector of
	symtab_index_entry instead of vector of
	std::unique_ptr<symtab_index_entry>.  All users adjusted to check
	whether an element's name is NULL instead of checking whether the
	element itself is NULL.
	(find_slot): Change return type.  Adjust.
	(hash_expand, , add_index_entry, uniquify_cu_indices)
	(write_hash_table): Adjust.
2017-06-12 17:06:26 +01:00
Pedro Alves
e8f8bcb35f .gdb_index prod perf regression: Estimate size of psyms_seen
Using the same test as the previous patch, perf shows GDB spending
over 7% in "free".  A substantial number of those calls comes from
insertions in the psyms_seen unordered_set causing lots of rehashing
and recreating buckets.  Fix this by computing an estimate of the size
of the set upfront.

Using the same test as in the previous patch, against the same gdb
inferior, timing improves ~8% further:

  ~6.5s => ~6.0s (average of 5 runs).

gdb/ChangeLog:
2017-06-12  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (recursively_count_psymbols): New function.
	(write_psymtabs_to_index): Call it to compute number of psyms and
	pass estimate size of psyms_seen to unordered_set's ctor.
2017-06-12 17:06:25 +01:00
Pedro Alves
70a1152bee .gdb_index prod perf regression: find before insert in unordered_map
"perf" shows the unordered_map::emplace call in write_hash_table a bit
high up on profiles.  Fix this using the find + insert idiom instead
of going straight to insert.

I tried doing the same to the other unordered_maps::emplace calls in
the file, but saw no performance improvement, so left them be.

With a '-g3 -O2' build of gdb, and:

  $ cat save-index.cmd
  set $i = 0
  while $i < 100
    save gdb-index .
    set $i = $i + 1
  end
  $ time ./gdb -data-directory=data-directory -nx --batch -q -x save-index.cmd  ./gdb.pristine

I get an improvement of ~7%:

  ~7.0s => ~6.5s (average of 5 runs).

gdb/ChangeLog:
2017-06-12  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (write_hash_table): Check if key already exists
	before emplacing.
2017-06-12 17:06:25 +01:00
Pedro Alves
c2f134ac41 Code cleanup: dwarf2read.c: Add data_buf::append_uint
This avoids having to specify the integer size twice in the same line.

gdb/ChangeLog:
2017-06-12  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (data_buf::append_space): Rename to...
	(data_buf::grow): ... this, and make private.  Adjust all callers.
	(data_buf::append_uint): New method.
	(add_address_entry, write_one_signatured_type)
	(write_psymtabs_to_index): Use it.
2017-06-12 17:06:25 +01:00
Pedro Alves
a81e6d4d26 Code cleanup: dwarf2read.c: Eliminate ::file_write
There's no real need for all this indirection.

gdb/ChangeLog:
2017-06-12  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (file_write(FILE *, const void *, size_t)): Delete.
	(file_write (FILE *, const std::vector<Elem>&)): Delete.
	(data_buf::file_write): Call ::fwrite directly.
2017-06-12 17:06:25 +01:00
Pedro Alves
6fd931f2d6 Code cleanup: dwarf2read.c:uniquify_cu_indices: Use std::unique
gdb/ChangeLog:
2017-06-12  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (uniquify_cu_indices): Use std::unique and
	std::vector::erase.
2017-06-12 17:06:25 +01:00
Jan Kratochvil
bc8f2430e0 Code cleanup: C++ify .gdb_index producer
gdb/ChangeLog
2017-06-12  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Code cleanup: C++ify .gdb_index producer.
	* dwarf2read.c: Include <unordered_set> and <unordered_map>.
	(MAYBE_SWAP) [WORDS_BIGENDIAN]: Cast to offset_type.
	(struct strtab_entry, hash_strtab_entry, eq_strtab_entry)
	(create_strtab, add_string): Remove.
	(file_write, data_buf): New.
	(struct symtab_index_entry): Use std::vector for cu_indices.
	(struct mapped_symtab): Use std::vector for data.
	(hash_symtab_entry, eq_symtab_entry, delete_symtab_entry)
	(create_symbol_hash_table, create_mapped_symtab, cleanup_mapped_symtab):
	Remove.
	(find_slot): Change return type.  Update it to the new data structures.
	(hash_expand, add_index_entry): Update it to the new data structures.
	(offset_type_compare): Remove.
	(uniquify_cu_indices): Update it to the new data structures.
	(c_str_view, c_str_view_hasher, vector_hasher): New.
	(add_indices_to_cpool): Remove.
	(write_hash_table): Update it to the new data structures.
	(struct psymtab_cu_index_map, hash_psymtab_cu_index)
	(eq_psymtab_cu_index): Remove.
	(psym_index_map): New typedef.
	(struct addrmap_index_data): Change addr_obstack pointer to data_buf
	reference and std::unordered_map for cu_index_htab.
	(add_address_entry, add_address_entry_worker, write_address_map)
	(write_psymbols): Update it to the new data structures.
	(write_obstack): Remove.
	(struct signatured_type_index_data): Change types_list to a data_buf
	reference and psyms_seen to a std::unordered_set reference.
	(write_one_signatured_type, recursively_write_psymbols)
	(write_psymtabs_to_index): Update it to the new data structures.
2017-06-12 16:29:53 +01:00
Simon Marchi
c4dcb155c4 Introduce "set debug separate-debug-file"
I helped someone figure out why their separate debug info (debug
link-based) was not found by gdb.  It turns out that the debug file was
not named properly.  It made me realize that it is quite difficult to
diagnose this kind of problems.  This patch adds some debug output to
show where GDB looks for those files, so that it should be (more)
obvious to find what's wrong.

Here's an example of the result, first with an example of unsuccessful lookup,
and then a successful one.

  (gdb) set debug separate-debug-file on
  (gdb) file /usr/bin/gnome-calculator
  Reading symbols from /usr/bin/gnome-calculator...
  Looking for separate debug info (build-id) for /usr/bin/gnome-calculator
    Trying /usr/local/lib/debug/.build-id/0d/5c5e8c86dbe4f4f95f7a13de04f91d377f3c6a.debug

  Looking for separate debug info (debug link) for /usr/bin/gnome-calculator
    Trying /usr/bin/5c5e8c86dbe4f4f95f7a13de04f91d377f3c6a.debug
    Trying /usr/bin/.debug/5c5e8c86dbe4f4f95f7a13de04f91d377f3c6a.debug
    Trying /usr/local/lib/debug//usr/bin/5c5e8c86dbe4f4f95f7a13de04f91d377f3c6a.debug
  (no debugging symbols found)...done.
  (gdb) set debug-file-directory /usr/lib/debug
  (gdb) file /usr/bin/gnome-calculator
  Reading symbols from /usr/bin/gnome-calculator...
  Looking for separate debug info by build-id for /usr/bin/gnome-calculator
    Trying /usr/lib/debug/.build-id/0d/5c5e8c86dbe4f4f95f7a13de04f91d377f3c6a.debug
  Reading symbols from /usr/lib/debug/.build-id/0d/5c5e8c86dbe4f4f95f7a13de04f91d377f3c6a.debug...done.
  done.

Note: here, the debug link happens to be named like the build-id, but it
doesn't have to be this way.  It puzzled me for a minute.

gdb/ChangeLog:

	* NEWS (Changes since GDB 8.0): Announce {set,show} debug
	separate-debug-file commands.
	* symfile.h (separate_debug_file_debug): New global.
	* symfile.c (separate_debug_file_debug): New global.
	(separate_debug_file_exists, find_separate_debug_file): Add
	debug output.
	(_initialize_symfile): Add "set debug separate-debug-file"
	command.
	* build-id.c (build_id_to_debug_bfd,
	find_separate_debug_file_by_buildid): Add debug output.

gdb/doc/ChangeLog:

	* gdb.texinfo (Optional Messages about Internal Happenings):
	Document {set,show} debug separate-debug-file commands.
2017-06-11 23:16:28 +02:00
Simon Marchi
6d45d4b42b gdbarch: Remove displaced_step_free_closure
The displaced_step_free_closure gdbarch hook allows architectures to
free data they might have allocated to complete a displaced step.
However, all architectures using that hook use the
simple_displaced_step_free_closure provided in arch-utils.{c,h}, which
does a simple xfree.  We can remove it and do an xfree directly instead
of calling the hook.

gdb/ChangeLog:

	* gdbarch.sh (displaced_step_free_closure): Remove.
	* gdbarch.h, gdbarch.c: Re-generate.
	* aarch64-linux-tdep.c (aarch64_linux_init_abi): Don't set
	displaced_step_free_closure.
	* amd64-linux-tdep.c (amd64_linux_init_abi_common): Likewise.
	* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
	* i386-linux-tdep.c (i386_linux_init_abi): Likewise.
	* rs6000-aix-tdep.c (rs6000_aix_init_osabi): Likewise.
	* rs6000-tdep.c (rs6000_gdbarch_init): Likewise.
	* s390-linux-tdep.c (s390_gdbarch_init): Likewise.
	* arch-utils.h (simple_displaced_step_free_closure): Remove.
	* arch-utils.c (simple_displaced_step_free_closure): Remove.
	* infrun.c (displaced_step_clear): Call xfree instead of
	gdbarch_displaced_step_free_closure.
2017-06-10 00:24:50 +02:00
Sergio Durigan Junior
2f91880f3a Fix possible bug when no args have been provided to the executable
Hi,

This bug is related to:

  <https://sourceware.org/ml/gdb-patches/2017-06/msg00216.html>

On stringify_argv, we have to check if args[0] is not NULL before
stringifying anything, otherwise we might do the wrong thing when
trimming the "ret" string in the end.  args[0] will be NULL when no
arguments are passed to the inferior that will be started.

Checked in as obvious.

gdb/ChangeLog:
2017-06-08  Sergio Durigan Junior  <sergiodj@redhat.com>

	* common/common-utils.c (stringify_argv): Check for "arg[0] !=
	NULL".
2017-06-08 16:58:25 -04:00
Alan Hayward
b8b6e72f3d Add MN10300_MAX_REGISTER_SIZE
gdb/
	* mn10300-tdep.c (MN10300_MAX_REGISTER_SIZE): Add.
	(mn10300_extract_return_value): Use MN10300_MAX_REGISTER_SIZE.
	(mn10300_push_dummy_call): Likewise.
2017-06-08 16:05:24 +01:00