1. Background information
The MIPS architecture, as originally designed and implemented in
mid-1980s has a uniform instruction word size that is 4 bytes, naturally
aligned. As such all MIPS instructions are located at addresses that
have their bits #1 and #0 set to zeroes, and any attempt to execute an
instruction from an address that has any of the two bits set to one
causes an address error exception. This may for example happen when a
jump-register instruction is executed whose register value used as the
jump target has any of these bits set.
Then in mid 1990s LSI sought a way to improve code density for their
TinyRISC family of MIPS cores and invented an alternatively encoded
instruction set in a joint effort with MIPS Technologies (then a
subsidiary of SGI). The new instruction set has been named the MIPS16
ASE (Application-Specific Extension) and uses a variable instruction
word size, which is 2 bytes (as the name of the ASE suggests) for most,
but there are a couple of exceptions that take 4 bytes, and then most of
the 2-byte instructions can be treated with a 2-byte extension prefix to
expand the range of the immediate operands used.
As a result instructions are no longer 4-byte aligned, instead they are
aligned to a multiple of 2. That left the bit #0 still unused for code
references, be it for the standard MIPS (i.e. as originally invented) or
for the MIPS16 instruction set, and based on that observation a clever
trick was invented that on one hand allowed the processor to be
seamlessly switched between the two instruction sets at any time at the
run time while on the other avoided the introduction of any special
control register to do that.
So it is the bit #0 of the instruction address that was chosen as the
selector and named the ISA bit. Any instruction executed at an even
address is interpreted as a standard MIPS instruction (the address still
has to have its bit #1 clear), any instruction executed at an odd
address is interpreted as a MIPS16 instruction.
To switch between modes ordinary jump instructions are used, such as
used for function calls and returns, specifically the bit #0 of the
source register used in jump-register instructions selects the execution
(ISA) mode for the following piece of code to be interpreted in.
Additionally new jump-immediate instructions were added that flipped the
ISA bit to select the opposite mode upon execution. They were
considered necessary to avoid the need to make register jumps in all
cases as the original jump-immediate instructions provided no way to
change the bit #0 at all.
This was all important for cases where standard MIPS and MIPS16 code had
to be mixed, either for compatibility with the existing binary code base
or to access resources not reachable from MIPS16 code (the MIPS16
instruction set only provides access to general-purpose registers, and
not for example floating-point unit registers or privileged coprocessor
0 registers) -- pieces of code in the opposite mode can be executed as
ordinary subroutine calls.
A similar approach has been more recently adopted for the MIPS16
replacement instruction set defined as the so called microMIPS ASE.
This is another instruction set encoding introduced to the MIPS
architecture. Just like the MIPS16 ASE, the microMIPS instruction set
uses a variable-length encoding, where each instruction takes a multiple
of 2 bytes. The ISA bit has been reused and for microMIPS-capable
processors selects between the standard MIPS and the microMIPS mode
instead.
2. Statement of the problem
To put it shortly, MIPS16 and microMIPS code pointers used by GDB are
different to these observed at the run time. This results in the same
expressions being evaluated producing different results in GDB and in
the program being debugged. Obviously it's the results obtained at the
run time that are correct (they define how the program behaves) and
therefore by definition the results obtained in GDB are incorrect.
A bit longer description will record that obviously at the run time the
ISA bit has to be set correctly (refer to background information above
if unsure why so) or the program will not run as expected. This is
recorded in all the executable file structures used at the run time: the
dynamic symbol table (but not always the static one!), the GOT, and
obviously in all the addresses embedded in code or data of the program
itself, calculated by applying the appropriate relocations at the static
link time.
While a program is being processed by GDB, the ISA bit is stripped off
from any code addresses, presumably to make them the same as the
respective raw memory byte address used by the processor to access the
instruction in the instruction fetch access cycle. This stripping is
actually performed outside GDB proper, in BFD, specifically
_bfd_mips_elf_symbol_processing (elfxx-mips.c, see the piece of code at
the very bottom of that function, starting with an: "If this is an
odd-valued function symbol, assume it's a MIPS16 or microMIPS one."
comment).
This function is also responsible for symbol table dumps made by
`objdump' too, so you'll never see the ISA bit reported there by that
tool, you need to use `readelf'.
This is however unlike what is ever done at the run time, the ISA bit
once present is never stripped off, for example a cast like this:
(short *) main
will not strip the ISA bit off and if the resulting pointer is intended
to be used to access instructions as data, for example for software
instruction decoding (like for fault recovery or emulation in a signal
handler) or for self-modifying code then the bit still has to be
stripped off by an explicit AND operation.
This is probably best illustrated with a simple real program example.
Let's consider the following simple program:
$ cat foobar.c
int __attribute__ ((mips16)) foo (void)
{
return 1;
}
int __attribute__ ((mips16)) bar (void)
{
return 2;
}
int __attribute__ ((nomips16)) foo32 (void)
{
return 3;
}
int (*foo32p) (void) = foo32;
int (*foop) (void) = foo;
int fooi = (int) foo;
int
main (void)
{
return foop ();
}
$
This is plain C with no odd tricks, except from the instruction mode
attributes. They are not necessary to trigger this problem, I just put
them here so that the program can be contained in a single source file
and to make it obvious which function is MIPS16 code and which is not.
Let's try it with Linux, so that everyone can repeat this experiment:
$ mips-linux-gnu-gcc -mips16 -g -O2 -o foobar foobar.c
$
Let's have a look at some interesting symbols:
$ mips-linux-gnu-readelf -s foobar | egrep 'table|foo|bar'
Symbol table '.dynsym' contains 7 entries:
Symbol table '.symtab' contains 95 entries:
55: 00000000 0 FILE LOCAL DEFAULT ABS foobar.c
66: 0040068c 4 FUNC GLOBAL DEFAULT [MIPS16] 12 bar
68: 00410848 4 OBJECT GLOBAL DEFAULT 21 foo32p
70: 00410844 4 OBJECT GLOBAL DEFAULT 21 foop
78: 00400684 8 FUNC GLOBAL DEFAULT 12 foo32
80: 00400680 4 FUNC GLOBAL DEFAULT [MIPS16] 12 foo
88: 00410840 4 OBJECT GLOBAL DEFAULT 21 fooi
$
Hmm, no sight of the ISA bit, but notice how foo and bar (but not
foo32!) have been marked as MIPS16 functions (ELF symbol structure's
`st_other' field is used for that).
So let's try to run and poke at this program with GDB. I'll be using a
native system for simplicity (I'll be using ellipses here and there to
remove unrelated clutter):
$ ./foobar
$ echo $?
1
$
So far, so good.
$ gdb ./foobar
[...]
(gdb) break main
Breakpoint 1 at 0x400490: file foobar.c, line 23.
(gdb) run
Starting program: .../foobar
Breakpoint 1, main () at foobar.c:23
23 return foop ();
(gdb)
Yay, it worked! OK, so let's poke at it:
(gdb) print main
$1 = {int (void)} 0x400490 <main>
(gdb) print foo32
$2 = {int (void)} 0x400684 <foo32>
(gdb) print foo32p
$3 = (int (*)(void)) 0x400684 <foo32>
(gdb) print bar
$4 = {int (void)} 0x40068c <bar>
(gdb) print foo
$5 = {int (void)} 0x400680 <foo>
(gdb) print foop
$6 = (int (*)(void)) 0x400681 <foo>
(gdb)
A-ha! Here's the difference and finally the ISA bit!
(gdb) print /x fooi
$7 = 0x400681
(gdb) p/x $pc
p/x $pc
$8 = 0x400491
(gdb)
And here as well...
(gdb) advance foo
foo () at foobar.c:4
4 }
(gdb) disassemble
Dump of assembler code for function foo:
0x00400680 <+0>: jr ra
0x00400682 <+2>: li v0,1
End of assembler dump.
(gdb) finish
Run till exit from #0 foo () at foobar.c:4
main () at foobar.c:24
24 }
Value returned is $9 = 1
(gdb) continue
Continuing.
[Inferior 1 (process 14103) exited with code 01]
(gdb)
So let's be a bit inquisitive...
(gdb) run
Starting program: .../foobar
Breakpoint 1, main () at foobar.c:23
23 return foop ();
(gdb)
Actually we do not like to run foo here at all. Let's run bar instead!
(gdb) set foop = bar
(gdb) print foop
$10 = (int (*)(void)) 0x40068c <bar>
(gdb)
Hmm, no ISA bit. Is it going to work?
(gdb) advance bar
bar () at foobar.c:9
9 }
(gdb) p/x $pc
$11 = 0x40068c
(gdb) disassemble
Dump of assembler code for function bar:
=> 0x0040068c <+0>: jr ra
0x0040068e <+2>: li v0,2
End of assembler dump.
(gdb) finish
Run till exit from #0 bar () at foobar.c:9
Program received signal SIGILL, Illegal instruction.
bar () at foobar.c:9
9 }
(gdb)
Oops!
(gdb) p/x $pc
$12 = 0x40068c
(gdb)
We're still there!
(gdb) continue
Continuing.
Program terminated with signal SIGILL, Illegal instruction.
The program no longer exists.
(gdb)
So let's try something else:
(gdb) run
Starting program: .../foobar
Breakpoint 1, main () at foobar.c:23
23 return foop ();
(gdb) set foop = foo
(gdb) advance foo
foo () at foobar.c:4
4 }
(gdb) disassemble
Dump of assembler code for function foo:
=> 0x00400680 <+0>: jr ra
0x00400682 <+2>: li v0,1
End of assembler dump.
(gdb) finish
Run till exit from #0 foo () at foobar.c:4
Program received signal SIGILL, Illegal instruction.
foo () at foobar.c:4
4 }
(gdb) continue
Continuing.
Program terminated with signal SIGILL, Illegal instruction.
The program no longer exists.
(gdb)
The same problem!
(gdb) run
Starting program:
/net/build2-lucid-cs/scratch/macro/mips-linux-fsf-gcc/isa-bit/foobar
Breakpoint 1, main () at foobar.c:23
23 return foop ();
(gdb) set foop = foo32
(gdb) advance foo32
foo32 () at foobar.c:14
14 }
(gdb) disassemble
Dump of assembler code for function foo32:
=> 0x00400684 <+0>: jr ra
0x00400688 <+4>: li v0,3
End of assembler dump.
(gdb) finish
Run till exit from #0 foo32 () at foobar.c:14
main () at foobar.c:24
24 }
Value returned is $14 = 3
(gdb) continue
Continuing.
[Inferior 1 (process 14113) exited with code 03]
(gdb)
That did work though, so it's the ISA bit only!
(gdb) quit
Enough!
That's the tip of the iceberg only though. So let's rebuild the
executable with some dynamic symbols:
$ mips-linux-gnu-gcc -mips16 -Wl,--export-dynamic -g -O2 -o foobar-dyn foobar.c
$ mips-linux-gnu-readelf -s foobar-dyn | egrep 'table|foo|bar'
Symbol table '.dynsym' contains 32 entries:
6: 004009cd 4 FUNC GLOBAL DEFAULT 12 bar
8: 00410b88 4 OBJECT GLOBAL DEFAULT 21 foo32p
9: 00410b84 4 OBJECT GLOBAL DEFAULT 21 foop
15: 004009c4 8 FUNC GLOBAL DEFAULT 12 foo32
17: 004009c1 4 FUNC GLOBAL DEFAULT 12 foo
25: 00410b80 4 OBJECT GLOBAL DEFAULT 21 fooi
Symbol table '.symtab' contains 95 entries:
55: 00000000 0 FILE LOCAL DEFAULT ABS foobar.c
69: 004009cd 4 FUNC GLOBAL DEFAULT 12 bar
71: 00410b88 4 OBJECT GLOBAL DEFAULT 21 foo32p
72: 00410b84 4 OBJECT GLOBAL DEFAULT 21 foop
79: 004009c4 8 FUNC GLOBAL DEFAULT 12 foo32
81: 004009c1 4 FUNC GLOBAL DEFAULT 12 foo
89: 00410b80 4 OBJECT GLOBAL DEFAULT 21 fooi
$
OK, now the ISA bit is there for a change, but the MIPS16 `st_other'
attribute gone, hmm... What does `objdump' do then:
$ mips-linux-gnu-objdump -Tt foobar-dyn | egrep 'SYMBOL|foo|bar'
foobar-dyn: file format elf32-tradbigmips
SYMBOL TABLE:
00000000 l df *ABS* 00000000 foobar.c
004009cc g F .text 00000004 0xf0 bar
00410b88 g O .data 00000004 foo32p
00410b84 g O .data 00000004 foop
004009c4 g F .text 00000008 foo32
004009c0 g F .text 00000004 0xf0 foo
00410b80 g O .data 00000004 fooi
DYNAMIC SYMBOL TABLE:
004009cc g DF .text 00000004 Base 0xf0 bar
00410b88 g DO .data 00000004 Base foo32p
00410b84 g DO .data 00000004 Base foop
004009c4 g DF .text 00000008 Base foo32
004009c0 g DF .text 00000004 Base 0xf0 foo
00410b80 g DO .data 00000004 Base fooi
$
Hmm, the attribute (0xf0, printed raw) is back, and the ISA bit gone
again.
Let's have a look at some DWARF-2 records GDB uses (I'll be stripping
off a lot here for brevity) -- debug info:
$ mips-linux-gnu-readelf -wi foobar
Contents of the .debug_info section:
[...]
Compilation Unit @ offset 0x88:
Length: 0xbb (32-bit)
Version: 4
Abbrev Offset: 62
Pointer Size: 4
<0><93>: Abbrev Number: 1 (DW_TAG_compile_unit)
<94> DW_AT_producer : (indirect string, offset: 0x19e): GNU C 4.8.0 20120513 (experimental) -meb -mips16 -march=mips32r2 -mhard-float -mllsc -mplt -mno-synci -mno-shared -mabi=32 -g -O2
<98> DW_AT_language : 1 (ANSI C)
<99> DW_AT_name : (indirect string, offset: 0x190): foobar.c
<9d> DW_AT_comp_dir : (indirect string, offset: 0x225): [...]
<a1> DW_AT_ranges : 0x0
<a5> DW_AT_low_pc : 0x0
<a9> DW_AT_stmt_list : 0x27
<1><ad>: Abbrev Number: 2 (DW_TAG_subprogram)
<ae> DW_AT_external : 1
<ae> DW_AT_name : foo
<b2> DW_AT_decl_file : 1
<b3> DW_AT_decl_line : 1
<b4> DW_AT_prototyped : 1
<b4> DW_AT_type : <0xc2>
<b8> DW_AT_low_pc : 0x400680
<bc> DW_AT_high_pc : 0x400684
<c0> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa)
<c2> DW_AT_GNU_all_call_sites: 1
<1><c2>: Abbrev Number: 3 (DW_TAG_base_type)
<c3> DW_AT_byte_size : 4
<c4> DW_AT_encoding : 5 (signed)
<c5> DW_AT_name : int
<1><c9>: Abbrev Number: 4 (DW_TAG_subprogram)
<ca> DW_AT_external : 1
<ca> DW_AT_name : (indirect string, offset: 0x18a): foo32
<ce> DW_AT_decl_file : 1
<cf> DW_AT_decl_line : 11
<d0> DW_AT_prototyped : 1
<d0> DW_AT_type : <0xc2>
<d4> DW_AT_low_pc : 0x400684
<d8> DW_AT_high_pc : 0x40068c
<dc> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa)
<de> DW_AT_GNU_all_call_sites: 1
<1><de>: Abbrev Number: 2 (DW_TAG_subprogram)
<df> DW_AT_external : 1
<df> DW_AT_name : bar
<e3> DW_AT_decl_file : 1
<e4> DW_AT_decl_line : 6
<e5> DW_AT_prototyped : 1
<e5> DW_AT_type : <0xc2>
<e9> DW_AT_low_pc : 0x40068c
<ed> DW_AT_high_pc : 0x400690
<f1> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa)
<f3> DW_AT_GNU_all_call_sites: 1
<1><f3>: Abbrev Number: 5 (DW_TAG_subprogram)
<f4> DW_AT_external : 1
<f4> DW_AT_name : (indirect string, offset: 0x199): main
<f8> DW_AT_decl_file : 1
<f9> DW_AT_decl_line : 21
<fa> DW_AT_prototyped : 1
<fa> DW_AT_type : <0xc2>
<fe> DW_AT_low_pc : 0x400490
<102> DW_AT_high_pc : 0x4004a4
<106> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa)
<108> DW_AT_GNU_all_tail_call_sites: 1
[...]
$
-- no sign of the ISA bit anywhere -- frame info:
$ mips-linux-gnu-readelf -wf foobar
[...]
Contents of the .debug_frame section:
00000000 0000000c ffffffff CIE
Version: 1
Augmentation: ""
Code alignment factor: 1
Data alignment factor: -4
Return address column: 31
DW_CFA_def_cfa_register: r29
DW_CFA_nop
00000010 0000000c 00000000 FDE cie=00000000 pc=00400680..00400684
00000020 0000000c 00000000 FDE cie=00000000 pc=00400684..0040068c
00000030 0000000c 00000000 FDE cie=00000000 pc=0040068c..00400690
00000040 00000018 00000000 FDE cie=00000000 pc=00400490..004004a4
DW_CFA_advance_loc: 6 to 00400496
DW_CFA_def_cfa_offset: 32
DW_CFA_offset: r31 at cfa-4
DW_CFA_advance_loc: 6 to 0040049c
DW_CFA_restore: r31
DW_CFA_def_cfa_offset: 0
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
[...]
$
-- no sign of the ISA bit anywhere -- range info (GDB doesn't use arange):
$ mips-linux-gnu-readelf -wR foobar
Contents of the .debug_ranges section:
Offset Begin End
00000000 00400680 00400690
00000000 00400490 004004a4
00000000 <End of list>
$
-- no sign of the ISA bit anywhere -- line info:
$ mips-linux-gnu-readelf -wl foobar
Raw dump of debug contents of section .debug_line:
[...]
Offset: 0x27
Length: 78
DWARF Version: 2
Prologue Length: 31
Minimum Instruction Length: 1
Initial value of 'is_stmt': 1
Line Base: -5
Line Range: 14
Opcode Base: 13
Opcodes:
Opcode 1 has 0 args
Opcode 2 has 1 args
Opcode 3 has 1 args
Opcode 4 has 1 args
Opcode 5 has 1 args
Opcode 6 has 0 args
Opcode 7 has 0 args
Opcode 8 has 0 args
Opcode 9 has 1 args
Opcode 10 has 0 args
Opcode 11 has 0 args
Opcode 12 has 1 args
The Directory Table is empty.
The File Name Table:
Entry Dir Time Size Name
1 0 0 0 foobar.c
Line Number Statements:
Extended opcode 2: set Address to 0x400681
Special opcode 6: advance Address by 0 to 0x400681 and Line by 1 to 2
Special opcode 7: advance Address by 0 to 0x400681 and Line by 2 to 4
Special opcode 55: advance Address by 3 to 0x400684 and Line by 8 to 12
Special opcode 7: advance Address by 0 to 0x400684 and Line by 2 to 14
Advance Line by -7 to 7
Special opcode 131: advance Address by 9 to 0x40068d and Line by 0 to 7
Special opcode 7: advance Address by 0 to 0x40068d and Line by 2 to 9
Advance PC by 3 to 0x400690
Extended opcode 1: End of Sequence
Extended opcode 2: set Address to 0x400491
Advance Line by 21 to 22
Copy
Special opcode 6: advance Address by 0 to 0x400491 and Line by 1 to 23
Special opcode 60: advance Address by 4 to 0x400495 and Line by -1 to 22
Special opcode 34: advance Address by 2 to 0x400497 and Line by 1 to 23
Special opcode 62: advance Address by 4 to 0x40049b and Line by 1 to 24
Special opcode 32: advance Address by 2 to 0x40049d and Line by -1 to 23
Special opcode 6: advance Address by 0 to 0x40049d and Line by 1 to 24
Advance PC by 7 to 0x4004a4
Extended opcode 1: End of Sequence
[...]
-- a-ha, the ISA bit is there! However it's not always right for some
reason, I don't have a small test case to show it, but here's an excerpt
from MIPS16 libc, a prologue of a function:
00019630 <__libc_init_first>:
19630: e8a0 jrc ra
19632: 6500 nop
00019634 <_init>:
19634: f000 6a11 li v0,17
19638: f7d8 0b08 la v1,15e00 <_DYNAMIC+0x15c54>
1963c: f400 3240 sll v0,16
19640: e269 addu v0,v1
19642: 659a move gp,v0
19644: 64f6 save 48,ra,s0-s1
19646: 671c move s0,gp
19648: d204 sw v0,16(sp)
1964a: f352 984c lw v0,-27828(s0)
1964e: 6724 move s1,a0
and the corresponding DWARF-2 line info:
Line Number Statements:
Extended opcode 2: set Address to 0x19631
Advance Line by 44 to 45
Copy
Special opcode 8: advance Address by 0 to 0x19631 and Line by 3 to 48
Special opcode 66: advance Address by 4 to 0x19635 and Line by 5 to 53
Advance PC by constant 17 to 0x19646
Special opcode 25: advance Address by 1 to 0x19647 and Line by 6 to 59
Advance Line by -6 to 53
Special opcode 33: advance Address by 2 to 0x19649 and Line by 0 to 53
Special opcode 39: advance Address by 2 to 0x1964b and Line by 6 to 59
Advance Line by -6 to 53
Special opcode 61: advance Address by 4 to 0x1964f and Line by 0 to 53
-- see that "Advance PC by constant 17" there? It clears the ISA bit,
however code at 0x19646 is not standard MIPS code at all. For some
reason the constant is always 17, I've never seen DW_LNS_const_add_pc
used with any other value -- is that a binutils bug or what?
3. Solution:
I think we should retain the value of the ISA bit in code references,
that is effectively treat them as cookies as they indeed are (although
trivially calculated) rather than raw memory byte addresses.
In a perfect world both the static symbol table and the respective
DWARF-2 records should be fixed to include the ISA bit in all the cases.
I think however that this is infeasible.
All the uses of `_bfd_mips_elf_symbol_processing' can not necessarily be
tracked down. This function is used by `elf_slurp_symbol_table' that in
turn is used by `bfd_canonicalize_symtab' and
`bfd_canonicalize_dynamic_symtab', which are public interfaces.
Similarly DWARF-2 records are used outside GDB, one notable if a bit
questionable is the exception unwinder (libgcc/unwind-dw2.c) -- I have
identified at least bits in `execute_cfa_program' and
`uw_frame_state_for', both around the calls to `_Unwind_IsSignalFrame',
that would need an update as they effectively flip the ISA bit freely;
see also the comment about MASK_RETURN_ADDR in gcc/config/mips/mips.h.
But there may be more places. Any change in how DWARF-2 records are
produced would require an update there and would cause compatibility
problems with libgcc.a binaries already distributed; given that this is
a static library a complex change involving function renames would
likely be required.
I propose therefore to accept the existing inconsistencies and deal with
them entirely within GDB. I have figured out that the ISA bit lost in
various places can still be recovered as long as we have symbol
information -- that'll have the `st_other' attribute correctly set to
one of standard MIPS/MIPS16/microMIPS encoding.
Here's the resulting change. It adds a couple of new `gdbarch' hooks,
one to update symbol information with the ISA bit lost in
`_bfd_mips_elf_symbol_processing', and two other ones to adjust DWARF-2
records as they're processed. The ISA bit is set in each address
handled according to information retrieved from the symbol table for the
symbol spanning the address if any; limits are adjusted based on the
address they point to related to the respective base address.
Additionally minimal symbol information has to be adjusted accordingly
in its gdbarch hook.
With these changes in place some complications with ISA bit juggling in
the PC that never fully worked can be removed from the MIPS backend.
Conversely, the generic dynamic linker event special breakpoint symbol
handler has to be updated to call the minimal symbol gdbarch hook to
record that the symbol is a MIPS16 or microMIPS address if applicable or
the breakpoint will be set at the wrong address and either fail to work
or cause SIGTRAPs (this is because the symbol is handled early on and
bypasses regular symbol processing).
4. Results obtained
The change fixes the example above -- to repeat only the crucial steps:
(gdb) break main
Breakpoint 1 at 0x400491: file foobar.c, line 23.
(gdb) run
Starting program: .../foobar
Breakpoint 1, main () at foobar.c:23
23 return foop ();
(gdb) print foo
$1 = {int (void)} 0x400681 <foo>
(gdb) set foop = bar
(gdb) advance bar
bar () at foobar.c:9
9 }
(gdb) disassemble
Dump of assembler code for function bar:
=> 0x0040068d <+0>: jr ra
0x0040068f <+2>: li v0,2
End of assembler dump.
(gdb) finish
Run till exit from #0 bar () at foobar.c:9
main () at foobar.c:24
24 }
Value returned is $2 = 2
(gdb) continue
Continuing.
[Inferior 1 (process 14128) exited with code 02]
(gdb)
-- excellent!
The change removes about 90 failures per MIPS16 multilib in mips-sde-elf
testing too, results for MIPS16 are now similar to that for standard
MIPS; microMIPS results are a bit worse because of host-I/O problems in
QEMU used instead of MIPSsim for microMIPS testing only:
=== gdb Summary ===
# of expected passes 14299
# of unexpected failures 187
# of expected failures 56
# of known failures 58
# of unresolved testcases 11
# of untested testcases 52
# of unsupported tests 174
MIPS16:
=== gdb Summary ===
# of expected passes 14298
# of unexpected failures 187
# of unexpected successes 2
# of expected failures 54
# of known failures 58
# of unresolved testcases 12
# of untested testcases 52
# of unsupported tests 174
microMIPS:
=== gdb Summary ===
# of expected passes 14149
# of unexpected failures 201
# of unexpected successes 2
# of expected failures 54
# of known failures 58
# of unresolved testcases 7
# of untested testcases 53
# of unsupported tests 175
2014-12-12 Maciej W. Rozycki <macro@codesourcery.com>
Maciej W. Rozycki <macro@mips.com>
Pedro Alves <pedro@codesourcery.com>
gdb/
* gdbarch.sh (elf_make_msymbol_special): Change type to `F',
remove `predefault' and `invalid_p' initializers.
(make_symbol_special): New architecture method.
(adjust_dwarf2_addr, adjust_dwarf2_line): Likewise.
(objfile, symbol): New declarations.
* arch-utils.h (default_elf_make_msymbol_special): Remove
prototype.
(default_make_symbol_special): New prototype.
(default_adjust_dwarf2_addr): Likewise.
(default_adjust_dwarf2_line): Likewise.
* mips-tdep.h (mips_unmake_compact_addr): New prototype.
* arch-utils.c (default_elf_make_msymbol_special): Remove
function.
(default_make_symbol_special): New function.
(default_adjust_dwarf2_addr): Likewise.
(default_adjust_dwarf2_line): Likewise.
* dwarf2-frame.c (decode_frame_entry_1): Call
`gdbarch_adjust_dwarf2_addr'.
* dwarf2loc.c (dwarf2_find_location_expression): Likewise.
* dwarf2read.c (create_addrmap_from_index): Likewise.
(process_psymtab_comp_unit_reader): Likewise.
(add_partial_symbol): Likewise.
(add_partial_subprogram): Likewise.
(process_full_comp_unit): Likewise.
(read_file_scope): Likewise.
(read_func_scope): Likewise. Call `gdbarch_make_symbol_special'.
(read_lexical_block_scope): Call `gdbarch_adjust_dwarf2_addr'.
(read_call_site_scope): Likewise.
(dwarf2_ranges_read): Likewise.
(dwarf2_record_block_ranges): Likewise.
(read_attribute_value): Likewise.
(dwarf_decode_lines_1): Call `gdbarch_adjust_dwarf2_line'.
(new_symbol_full): Call `gdbarch_adjust_dwarf2_addr'.
* elfread.c (elf_symtab_read): Don't call
`gdbarch_elf_make_msymbol_special' if unset.
* mips-linux-tdep.c (micromips_linux_sigframe_validate): Strip
the ISA bit from the PC.
* mips-tdep.c (mips_unmake_compact_addr): New function.
(mips_elf_make_msymbol_special): Set the ISA bit in the symbol's
address appropriately.
(mips_make_symbol_special): New function.
(mips_pc_is_mips): Set the ISA bit before symbol lookup.
(mips_pc_is_mips16): Likewise.
(mips_pc_is_micromips): Likewise.
(mips_pc_isa): Likewise.
(mips_adjust_dwarf2_addr): New function.
(mips_adjust_dwarf2_line): Likewise.
(mips_read_pc, mips_unwind_pc): Keep the ISA bit.
(mips_addr_bits_remove): Likewise.
(mips_skip_trampoline_code): Likewise.
(mips_write_pc): Don't set the ISA bit.
(mips_eabi_push_dummy_call): Likewise.
(mips_o64_push_dummy_call): Likewise.
(mips_gdbarch_init): Install `mips_make_symbol_special',
`mips_adjust_dwarf2_addr' and `mips_adjust_dwarf2_line' gdbarch
handlers.
* solib.c (gdb_bfd_lookup_symbol_from_symtab): Get
target-specific symbol address adjustments.
* gdbarch.h: Regenerate.
* gdbarch.c: Regenerate.
2014-12-12 Maciej W. Rozycki <macro@codesourcery.com>
gdb/testsuite/
* gdb.base/func-ptrs.c: New file.
* gdb.base/func-ptrs.exp: New file.
During armv7b testing gdb.base/store.exp test was failling with
'GDB internal error' with the following message:
Temporary breakpoint 1, wack_double (u=
../../binutils-gdb/gdb/regcache.c:177: internal-error: register_size: Assertion `regnum >= 0 && regnum < (gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch))' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
It turns out that compiler generated DWARF with non-existent
register numbers. The compiler issue is present in both little endian
(armv7) and big endian (armv7b) (it is separate issue). Here is
example for one of formal parameters of wack_double function:
<2><792>: Abbrev Number: 10 (DW_TAG_formal_parameter)
<793> DW_AT_name : u
<795> DW_AT_decl_file : 1
<796> DW_AT_decl_line : 115
<797> DW_AT_type : <0x57c>
<79b> DW_AT_location : 6 byte block: 6d 93 4 6c 93 4 (DW_OP_reg29 (r29); DW_OP_piece: 4; DW_OP_reg28 (r28); DW_OP_piece: 4)
In both big and little endian cases gdbarch_dwarf2_reg_to_regnum
returns -1 which is stored into gdb_regnum. But it causes severe
problem only in big endian case because in read_pieced_value and
write_pieced_value functions BFD_ENDIAN_BIG related processing
happen regardless of gdb_regnum value, for example register_size
function is called and in case of gdb_regnum=-1, it cause
'GDB internal error' and crash.
Solution is to move BFD_ENDIAN_BIG related processing under
(gdb_regnum != -1) branch of processing.
gdb/ChangeLog:
2014-11-02 Victor Kamensky <victor.kamensky@linaro.org>
* dwarf2loc.c (read_pieced_value): Do big endian
processing only if gdb_regnum is not -1.
(write_pieced_value): Ditto.
This fixes PR symtab/14604, PR symtab/14605, and Jan's test at
https://sourceware.org/ml/gdb-patches/2014-07/msg00158.html, in a tree
with bddbbed reverted:
2014-07-22 Pedro Alves <palves@redhat.com>
* value.c (allocate_optimized_out_value): Don't mark value as
non-lazy.
The PRs are about variables described by the DWARF as being split over
multiple registers using DWARF piece information, but some of those
registers being marked as optimised out (not saved) by a later frame.
GDB currently incorrectly mishandles these partially-optimized-out
values.
Even though we can usually tell from the debug info whether a local or
global is optimized out, handling the case of a local living in a
register that was not saved in a frame requires fetching the variable.
GDB also needs to fetch a value to tell whether parts of it are
"<unavailable>". Given this, it's not worth it to try to avoid
fetching lazy optimized-out values based on debug info alone.
So this patch makes GDB track which chunks of a value's contents are
optimized out like it tracks <unavailable> contents. That is, it
makes value->optimized_out be a bit range vector instead of a boolean,
and removes the struct lval_funcs check_validity and check_any_valid
hooks.
Unlike Andrew's series which this is based on (at
https://sourceware.org/ml/gdb-patches/2013-08/msg00300.html, note some
pieces have gone in since), this doesn't merge optimized out and
unavailable contents validity/availability behind a single interface,
nor does it merge the bit range vectors themselves (at least yet).
While it may be desirable to have a single entry point that returns
existence of contents irrespective of what may make them
invalid/unavailable, several places want to treat optimized out /
unavailable / etc. differently, so each spot that potentially could
use it will need to be careful considered on case-by-case basis, and
best done as a separate change.
This fixes Jan's test, because value_available_contents_eq wasn't
considering optimized out value contents. It does now, and because of
that it's been renamed to value_contents_eq.
A new intro comment is added to value.h describing "<optimized out>",
"<not saved>" and "<unavailable>" values.
gdb/
PR symtab/14604
PR symtab/14605
* ada-lang.c (coerce_unspec_val_to_type): Use
value_contents_copy_raw.
* ada-valprint.c (val_print_packed_array_elements): Adjust.
* c-valprint.c (c_val_print): Use value_bits_any_optimized_out.
* cp-valprint.c (cp_print_value_fields): Let the common printing
code handle optimized out values.
(cp_print_value_fields_rtti): Use value_bits_any_optimized_out.
* d-valprint.c (dynamic_array_type): Use
value_bits_any_optimized_out.
* dwarf2loc.c (entry_data_value_funcs): Remove check_validity and
check_any_valid fields.
(check_pieced_value_bits): Delete and inline ...
(check_pieced_synthetic_pointer): ... here.
(check_pieced_value_validity): Delete.
(check_pieced_value_invalid): Delete.
(pieced_value_funcs): Remove check_validity and check_any_valid
fields.
(read_pieced_value): Use mark_value_bits_optimized_out.
(write_pieced_value): Switch to use
mark_value_bytes_optimized_out.
(dwarf2_evaluate_loc_desc_full): Copy the value contents instead
of assuming the whole value is optimized out.
* findvar.c (read_frame_register_value): Remove special handling
of optimized out registers.
(value_from_register): Use mark_value_bytes_optimized_out.
* frame-unwind.c (frame_unwind_got_optimized): Use
mark_value_bytes_optimized_out.
* jv-valprint.c (java_value_print): Adjust.
(java_print_value_fields): Let the common printing code handle
optimized out values.
* mips-tdep.c (mips_print_register): Remove special handling of
optimized out registers.
* opencl-lang.c (lval_func_check_validity): Delete.
(lval_func_check_any_valid): Delete.
(opencl_value_funcs): Remove check_validity and check_any_valid
fields.
* p-valprint.c (pascal_object_print_value_fields): Let the common
printing code handle optimized out values.
* stack.c (read_frame_arg): Remove special handling of optimized
out values. Fetch both VAL and ENTRYVAL before comparing
contents. Adjust to value_available_contents_eq rename.
* valprint.c (valprint_check_validity)
(val_print_scalar_formatted): Use value_bits_any_optimized_out.
(val_print_array_elements): Adjust.
* value.c (struct value) <optimized_out>: Now a VEC(range_s).
(value_bits_any_optimized_out): New function.
(value_entirely_covered_by_range_vector): New function, factored
out from value_entirely_unavailable.
(value_entirely_unavailable): Reimplement.
(value_entirely_optimized_out): New function.
(insert_into_bit_range_vector): New function, factored out from
mark_value_bits_unavailable.
(mark_value_bits_unavailable): Reimplement.
(struct ranges_and_idx): New struct.
(find_first_range_overlap_and_match): New function, factored out
from value_available_contents_bits_eq.
(value_available_contents_bits_eq): Rename to ...
(value_contents_bits_eq): ... this. Check both unavailable
contents and optimized out contents.
(value_available_contents_eq): Rename to ...
(value_contents_eq): ... this.
(allocate_value_lazy): Remove reference to the old optimized_out
boolean.
(allocate_optimized_out_value): Use
mark_value_bytes_optimized_out.
(require_not_optimized_out): Adjust to check whether the
optimized_out vec is empty.
(ranges_copy_adjusted): New function, factored out from
value_contents_copy_raw.
(value_contents_copy_raw): Also copy the optimized out ranges.
Assert the destination ranges aren't optimized out.
(value_contents_copy): Update comment, remove call to
require_not_optimized_out.
(value_contents_equal): Adjust to check whether the optimized_out
vec is empty.
(set_value_optimized_out, value_optimized_out_const): Delete.
(mark_value_bytes_optimized_out, mark_value_bits_optimized_out):
New functions.
(value_entirely_optimized_out, value_bits_valid): Delete.
(value_copy): Take a VEC copy of the 'optimized_out' field.
(value_primitive_field): Remove special handling of optimized out.
(value_fetch_lazy): Assert that lazy values have no unavailable
regions. Use value_bits_any_optimized_out. Remove some special
handling for optimized out values.
* value.h: Add intro comment about <optimized out> and
<unavailable>.
(struct lval_funcs): Remove check_validity and check_any_valid
fields.
(set_value_optimized_out, value_optimized_out_const): Remove.
(mark_value_bytes_optimized_out, mark_value_bits_optimized_out):
New declarations.
(value_bits_any_optimized_out): New declaration.
(value_bits_valid): Delete declaration.
(value_available_contents_eq): Rename to ...
(value_contents_eq): ... this, and extend comments.
gdb/testsuite/
PR symtab/14604
PR symtab/14605
* gdb.dwarf2/dw2-op-out-param.exp: Remove kfail branches and use
gdb_test.
I cannot reproduce any wrong case having the code removed.
I just do not find it correct to have it disabled. But at the same time I do
like much / I do not find correct the code myself. It is a bit problematic to
have struct value describing a memory content which is no longer present
there.
What happens there:
------------------------------------------------------------------------------
volatile int vv;
static __attribute__((noinline)) int
bar (int &ref) {
ref = 20;
vv++; /* break-here */
return ref;
}
int main (void) {
int var = 10;
return bar (var);
}
------------------------------------------------------------------------------
<4><c7>: Abbrev Number: 13 (DW_TAG_GNU_call_site_parameter)
<c8> DW_AT_location : 1 byte block: 55 (DW_OP_reg5 (rdi))
<ca> DW_AT_GNU_call_site_value: 2 byte block: 91 74 (DW_OP_fbreg: -12)
<cd> DW_AT_GNU_call_site_data_value: 1 byte block: 3a (DW_OP_lit10)
------------------------------------------------------------------------------
gdb -ex 'b value_addr' -ex r --args ../gdb ./1 -ex 'watch vv' -ex r -ex 'p &ref@entry'
->
6 return ref;
bar (ref=@0x7fffffffd944: 20, ref@entry=@0x7fffffffd944: 10) at 1.C:25
------------------------------------------------------------------------------
At /* break-here */ struct value variable 'ref' is TYPE_CODE_REF.
With FSF GDB HEAD:
(gdb) x/gx arg1.contents
0x6004000a4ad0: 0x00007fffffffd944
(gdb) p ((struct value *)arg1.location.computed.closure).lval
$1 = lval_memory
(gdb) p/x ((struct value *)arg1.location.computed.closure).location.address
$3 = 0x7fffffffd944
With your #if0-ed code:
(gdb) x/gx arg1.contents
0x6004000a4ad0: 0x00007fffffffd944
(gdb) p ((struct value *)arg1.location.computed.closure).lval
$8 = not_lval
(gdb) p/x ((struct value *)arg1.location.computed.closure).location.address
$9 = 0x0
I do not see how to access
((struct value *)arg1.location.computed.closure).location.address
from GDB CLI. Trying
(gdb) p &ref@entry
will invoke value_addr()'s:
if (TYPE_CODE (type) == TYPE_CODE_REF)
/* Copy the value, but change the type from (T&) to (T*). We
keep the same location information, which is efficient, and
allows &(&X) to get the location containing the reference. */
and therefore the address gets fetched already from
arg1.contents
and not from
((struct value *)arg1.location.computed.closure).location.address
.
And for any other type than TYPE_CODE_REF this code you removed does not get
executed at all. This DW_AT_GNU_call_site_data_value DWARF was meant
primarily for Fortran but with -O0 entry values do not get produced
and with -Og and higher Fortran always optimizes out the passing by reference.
If you do not like the removed code there I am OK with removing it as I do not
know how to make it's use reproducible for user anyway. In the worst case
- if there really is some way how to exploit it - one should just get
Attempt to take address of value not located in memory.
instead of some wrong value and it may be easy to fix then.
gdb/
2014-07-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* dwarf2loc.c (value_of_dwarf_reg_entry): Remove setting value address
for reference entry value target data value.
Message-ID: <20140720150727.GA18488@host2.jankratochvil.net>
This patch fixes a problem that prevented use of the Dwarf unwinders on SPU,
because dwarf2-frame.c common code did not support the situation where the
stack and/or frame pointer is maintained in a *vector* register. This is
because read_addr_from_reg is hard-coded to assume that such pointers can
be read from registers via a simple get_frame_register / unpack_pointer
operation.
Now, there *is* a routine address_from_register that calls into the
appropriate tdep routines to handle pointer values in "weird" registers
like on SPU, but it turns out I cannot simply change dwarf2-frame.c to
use address_from_register. This is because address_from_register uses
value_from_register to create a (temporary) value, and that routine
at some point calls get_frame_id in order to set up that value's
VALUE_FRAME_ID entry.
However, the dwarf2-frame.c read_addr_from_reg routine will be called
during early unwinding (to unwind the frame's CFA), at which point the
frame's ID is not actually known yet! This would cause an assert.
On the other hand, we may notice that VALUE_FRAME_ID is only needed in the
value returned by value_from_register if that value is later used as an
lvalue. But this is obviously never done to the temporary value used in
address_from_register. So, if we could change address_from_register to
not call value_from_register but instead accept constructing a value
that doesn't have VALUE_FRAME_ID set, things should be fine.
To do that, we can change the value_from_register callback to accept
a FRAME_ID instead of a FRAME; the only existing uses of the FRAME
argument were either to extract its frame ID, or its gdbarch. (To
keep a way of getting at the latter, we also change the callback's
type from "f" to "m".) Together with the required follow-on changes
in the existing value_from_register implementations (including the
default one), this seems to fix the problem.
As another minor interface cleanup, I've removed the explicit TYPE
argument from address_from_register. This routine really always
uses a default pointer type, and in the new implementation it -to
some extent- relies on that fact, in that it will now no longer
handle types that require gdbarch_convert_register_p handling.
gdb:
2014-04-17 Ulrich Weigand <uweigand@de.ibm.com>
* gdbarch.sh (value_from_register): Make class "m" instead of "f".
Replace FRAME argument with FRAME_ID.
* gdbarch.c, gdbarch.h: Regenerate.
* findvar.c (default_value_from_register): Add GDBARCH argument;
replace FRAME by FRAME_ID. No longer call get_frame_id.
(value_from_register): Update call to gdbarch_value_from_register.
* value.h (default_value_from_register): Update prototype.
* s390-linux-tdep.c (s390_value_from_register): Update interface
and call to default_value_from_register.
* spu-tdep.c (spu_value_from_register): Likewise.
* findvar.c (address_from_register): Remove TYPE argument.
Do not call value_from_register; use gdbarch_value_from_register
with null_frame_id instead.
* value.h (address_from_register): Update prototype.
* dwarf2-frame.c (read_addr_from_reg): Use address_from_register.
* dwarf2loc.c (dwarf_expr_read_addr_from_reg): Update for
address_from_register interface change.
The dwarf standard allow certain attributes to be expressed as dwarf
expressions rather than constants. For instance upper-/lowerbound attributes.
In case of a c99 variable length array the upperbound is a dynamic attribute.
With this change c99 vla behave the same as with static arrays.
1| void foo (size_t n) {
2| int ary[n];
3| memset(ary, 0, sizeof(ary));
4| }
(gdb) print ary
$1 = {0 <repeats 42 times>}
gdb/ChangeLog:
* dwarf2loc.c (dwarf2_locexpr_baton_eval): New function.
(dwarf2_evaluate_property): New function.
* dwarf2loc.h (dwarf2_evaluate_property): New function prototype.
* dwarf2read.c (attr_to_dynamic_prop): New function.
(read_subrange_type): Use attr_to_dynamic_prop to read high bound
attribute.
* gdbtypes.c: Include dwarf2loc.h.
(is_dynamic_type): New function.
(resolve_dynamic_type): New function.
(resolve_dynamic_bounds): New function.
(get_type_length): New function.
(check_typedef): Use get_type_length to compute type length.
* gdbtypes.h (TYPE_HIGH_BOUND_KIND): New macro.
(TYPE_LOW_BOUND_KIND): New macro.
(is_dynamic_type): New function prototype.
* value.c (value_from_contents_and_address): Call resolve_dynamic_type
to resolve dynamic properties of the type. Update comment.
* valops.c (get_value_at, value_at, value_at_lazy): Update comment.
This reverts the following patch series, as they cause some regresssions.
commit 37c1ab67a3
type: add c99 variable length array support
gdb/
* dwarf2loc.c (dwarf2_locexpr_baton_eval): New function.
(dwarf2_evaluate_property): New function.
* dwarf2loc.h (dwarf2_evaluate_property): New function prototype.
* dwarf2read.c (attr_to_dynamic_prop): New function.
(read_subrange_type): Use attr_to_dynamic_prop to read high bound
attribute.
* gdbtypes.c: Include dwarf2loc.h.
(is_dynamic_type): New function.
(resolve_dynamic_type): New function.
(resolve_dynamic_bounds): New function.
(get_type_length): New function.
(check_typedef): Use get_type_length to compute type length.
* gdbtypes.h (TYPE_HIGH_BOUND_KIND): New macro.
(TYPE_LOW_BOUND_KIND): New macro.
(is_dynamic_type): New function prototype.
* value.c (value_from_contents_and_address): Call resolve_dynamic_type
to resolve dynamic properties of the type. Update comment.
* valops.c (get_value_at, value_at, value_at_lazy): Update comment.
commit 26cb189f8b
vla: enable sizeof operator to work with variable length arrays
gdb/
* eval.c (evaluate_subexp_for_sizeof) <OP_VAR_VALUE>: If the type
passed to sizeof is dynamic evaluate the argument to compute the length.
commit 04b19544ef
vla: enable sizeof operator for indirection
gdb/
* eval.c (evaluate_subexp_for_sizeof) <UNOP_IND>: Create an indirect
value and retrieve the dynamic type size.
commit bcd629a44f
vla: update type from newly created value
gdb/
* ada-lang.c (ada_value_primitive_packed_val): Re-fetch type from value.
(ada_template_to_fixed_record_type_1): Likewise.
(ada_to_fixed_type_1): Likewise.
* cp-valprint.c (cp_print_value_fields_rtti): Likewise.
(cp_print_value): Likewise.
* d-valprint.c (dynamic_array_type): Likewise.
* eval.c (evaluate_subexp_with_coercion): Likewise.
* findvar.c (address_of_variable): Likewise.
* jv-valprint.c (java_value_print): Likewise.
* valops.c (value_ind): Likewise.
* value.c (coerce_ref): Likewise.
commit b86138fb04
vla: print "variable length" for unresolved dynamic bounds
gdb/
* c-typeprint.c (c_type_print_varspec_suffix): Added
check for not yet resolved high bound. If unresolved, print
"variable length" string to the console instead of random
length.
commit e1969afbd4
vla: support for DW_AT_count
gdb/
* dwarf2read.c (read_subrange_type): Convert DW_AT_count to a dynamic
property and store it as the high bound and flag the range accordingly.
* gdbtypes.c (resolve_dynamic_bounds): If range is flagged as
RANGE_UPPER_BOUND_IS_COUNT assign low + high - 1 as the new high bound.
* gdbtypes.h (enum range_flags): New enum.
(struct range_bounds): Add flags member.
commit 92b09522dc
vla: resolve dynamic bounds if value contents is a constant byte-sequence
gdb/
* findvar.c (default_read_var_value): Resolve dynamic bounds if location
points to a constant blob.
commit 3bce82377f
vla: evaluate operand of sizeof if its type is a vla
gdb/
* eval.c (evaluate_subexp_for_sizeof): Add enum noside argument.
(evaluate_subexp_standard): Pass noside argument.
(evaluate_subexp_for_sizeof) <BINOP_SUBSCRIPT>: Handle subscript case
if noside equals EVAL_NORMAL. If the subscript yields a vla type
re-evaluate subscript operation with EVAL_NORMAL to enable sideffects.
* gdbtypes.c (resolve_dynamic_bounds): Mark bound as evaluated.
* gdbtypes.h (enum range_flags): Add RANGE_EVALUATED case.
gdb/testsuite
* gdb.base/vla-sideeffect.c: New file.
* gdb.base/vla-sideeffect.exp: New file.
commit 504f34326e
test: cover subranges with present DW_AT_count attribute
gdb/testsuite/
* gdb.dwarf2/count.exp: New file.
commit 1a237e0ee5
test: multi-dimensional c99 vla.
gdb/testsuite/
* gdb.base/vla-multi.c: New file.
* gdb.base/vla-multi.exp: New file.
commit 024e13b46f
test: evaluate pointers to C99 vla correctly.
gdb/testsuite/
* gdb.base/vla-ptr.c: New file.
* gdb.base/vla-ptr.exp: New file.
commit c8655f75e2
test: basic c99 vla tests for C primitives
gdb/testsuite/
* gdb.base/vla-datatypes.c: New file.
* gdb.base/vla-datatypes.exp: New file.
commit 58a84dcf29
test: add mi vla test
gdb/testsuite/
* gdb.mi/mi-vla-c99.exp: New file.
* gdb.mi/vla.c: New file.
The dwarf standard allow certain attributes to be expressed as dwarf
expressions rather than constants. For instance upper-/lowerbound attributes.
In case of a c99 variable length array the upperbound is a dynamic attribute.
With this change c99 vla behave the same as with static arrays.
1| void foo (size_t n) {
2| int ary[n];
3| memset(ary, 0, sizeof(ary));
4| }
(gdb) print ary
$1 = {0 <repeats 42 times>}
* dwarf2loc.c (dwarf2_locexpr_baton_eval): New function.
(dwarf2_evaluate_property): New function.
* dwarf2loc.h (dwarf2_evaluate_property): New function prototype.
* dwarf2read.c (attr_to_dynamic_prop): New function.
(read_subrange_type): Use attr_to_dynamic_prop to read high bound
attribute.
* gdbtypes.c: Include dwarf2loc.h.
(is_dynamic_type): New function.
(resolve_dynamic_type): New function.
(resolve_dynamic_bounds): New function.
(get_type_length): New function.
(check_typedef): Use get_type_length to compute type length.
* gdbtypes.h (TYPE_HIGH_BOUND_KIND): New macro.
(TYPE_LOW_BOUND_KIND): New macro.
(is_dynamic_type): New function prototype.
* value.c (value_from_contents_and_address): Call resolve_dynamic_type
to resolve dynamic properties of the type. Update comment.
* valops.c (get_value_at, value_at, value_at_lazy): Update comment.
This removes XCALLOC and replaces it either with XCNEWVEC, or, if the
number of elements being requested was 1, with XCNEW.
2014-01-13 Tom Tromey <tromey@redhat.com>
* defs.h (XCALLOC): Remove.
* bcache.c (bcache_xmalloc): Use XCNEW, not XCALLOC.
(print_bcache_statistics): Use XCNEWVEC, not XCALLOC.
* dwarf2loc.c (allocate_piece_closure): Likewise.
* elfread.c (elf_symfile_segments): Likewise.
(elf_symfile_segments): Likewise.
* gdbtypes.c (copy_type_recursive): Likewise.
* i386-tdep.c (i386_gdbarch_init): Use XCNEW, not XCALLOC.
* jit.c (jit_frame_sniffer): Use XCNEWVEC, not XCALLOC.
* minsyms.c (prim_record_minimal_symbol_full): Use XCNEW, not
XCALLOC.
* mt-tdep.c (mt_gdbarch_init): Likewise.
* opencl-lang.c (allocate_lval_closure): Use XCNEWVEC, not
XCALLOC.
* psymtab.c (psymbol_compare): Use XCNEW, not XCALLOC.
* regcache.c (regcache_xmalloc_1): Use XCNEWVEC, not XCALLOC.
* registry.c (registry_alloc_data): Likewise.
* rs6000-tdep.c (rs6000_gdbarch_init): Use XCNEW, not XCALLOC.
* s390-linux-tdep.c (s390_gdbarch_init): Likewise.
* serial.c (serial_fdopen_ops): Likewise.
* solib-aix.c (solib_aix_get_section_offsets): Use XCNEWVEC, not
XCALLOC.
* spu-tdep.c (spu_gdbarch_init): Use XCNEW, not XCALLOC.
* symfile.c (default_symfile_segments): Use XCNEW and XCNEWVEC,
not XCALLOC.
https://sourceware.org/ml/gdb-patches/2013-12/msg00144.html
The vector of unavailable parts of a value is currently byte based. Given
that we can model a value down to the bit level, we can potentially loose
information with the current implementation. After this patch we model the
unavailable information in bits.
gdb/ChangeLog
* dwarf2loc.c (read_pieced_value): Mark bits, not bytes
unavailable, use correct bit length.
* value.c (struct value): Extend comment on unavailable to
indicate that it is bit based.
(value_bits_available): New function.
(value_bytes_available): Call value_bits_available.
(value_entirely_available): Check against the bit length, not byte
length.
(mark_value_bits_unavailable): New function.
(mark_value_bytes_unavailable): Move contents to
mark_value_bits_unavailable, call to same.
(memcmp_with_bit_offsets): New function.
(value_available_contents_bits_eq): New function, takes the
functionality from value_available_contents_eq but uses
memcmp_with_bit_offsets now, and is bit not byte based.
(value_available_contents_eq): Move implementation into
value_available_contents_bits_eq, call to same.
(value_contents_copy_raw): Work on bits, not bytes.
(unpack_value_bits_as_long_1): Check availability in bits, not
bytes.
* value.h (value_bits_available): Declare new function.
(mark_value_bits_unavailable): Declare new function.
gdb/testsuite/ChangeLog
* gdb.trace/unavailable-dwarf-piece.c: New file.
* gdb.trace/unavailable-dwarf-piece.exp: New file.
In order to catch <optimized out> errors like we catch <unavailable>
errors, this adds a new OPTIMIZED_OUT_ERROR error code, and throws it
in various places.
gdb/ChangeLog
2013-12-06 Andrew Burgess <aburgess@broadcom.com>
Pedro Alves <palves@redhat.com>
* exceptions.h (errors): Add OPTIMIZED_OUT_ERROR.
* dwarf2loc.c (write_pieced_value): Throw OPTIMIZED_OUT_ERROR.
* frame.c (frame_unwind_register): Throw OPTIMIZED_OUT_ERROR.
* spu-tdep.c (spu_software_single_step): Throw
OPTIMIZED_OUT_ERROR.
* valops.c (value_assign): Throw OPTIMIZED_OUT_ERROR.
This removes gdb_string.h. This patch is purely mechanical. I
created it by running the two commands:
git rm common/gdb_string.h
perl -pi -e's/"gdb_string.h"/<string.h>/;' *.[chyl] */*.[chyl]
2013-11-18 Tom Tromey <tromey@redhat.com>
* common/gdb_string.h: Remove.
* aarch64-tdep.c: Use string.h, not gdb_string.h.
* ada-exp.y: Use string.h, not gdb_string.h.
* ada-lang.c: Use string.h, not gdb_string.h.
* ada-lex.l: Use string.h, not gdb_string.h.
* ada-typeprint.c: Use string.h, not gdb_string.h.
* ada-valprint.c: Use string.h, not gdb_string.h.
* aix-thread.c: Use string.h, not gdb_string.h.
* alpha-linux-tdep.c: Use string.h, not gdb_string.h.
* alpha-mdebug-tdep.c: Use string.h, not gdb_string.h.
* alpha-nat.c: Use string.h, not gdb_string.h.
* alpha-osf1-tdep.c: Use string.h, not gdb_string.h.
* alpha-tdep.c: Use string.h, not gdb_string.h.
* alphanbsd-tdep.c: Use string.h, not gdb_string.h.
* amd64-dicos-tdep.c: Use string.h, not gdb_string.h.
* amd64-linux-nat.c: Use string.h, not gdb_string.h.
* amd64-linux-tdep.c: Use string.h, not gdb_string.h.
* amd64-nat.c: Use string.h, not gdb_string.h.
* amd64-sol2-tdep.c: Use string.h, not gdb_string.h.
* amd64fbsd-tdep.c: Use string.h, not gdb_string.h.
* amd64obsd-tdep.c: Use string.h, not gdb_string.h.
* arch-utils.c: Use string.h, not gdb_string.h.
* arm-linux-nat.c: Use string.h, not gdb_string.h.
* arm-linux-tdep.c: Use string.h, not gdb_string.h.
* arm-tdep.c: Use string.h, not gdb_string.h.
* arm-wince-tdep.c: Use string.h, not gdb_string.h.
* armbsd-tdep.c: Use string.h, not gdb_string.h.
* armnbsd-nat.c: Use string.h, not gdb_string.h.
* armnbsd-tdep.c: Use string.h, not gdb_string.h.
* armobsd-tdep.c: Use string.h, not gdb_string.h.
* avr-tdep.c: Use string.h, not gdb_string.h.
* ax-gdb.c: Use string.h, not gdb_string.h.
* ax-general.c: Use string.h, not gdb_string.h.
* bcache.c: Use string.h, not gdb_string.h.
* bfin-tdep.c: Use string.h, not gdb_string.h.
* breakpoint.c: Use string.h, not gdb_string.h.
* build-id.c: Use string.h, not gdb_string.h.
* buildsym.c: Use string.h, not gdb_string.h.
* c-exp.y: Use string.h, not gdb_string.h.
* c-lang.c: Use string.h, not gdb_string.h.
* c-typeprint.c: Use string.h, not gdb_string.h.
* c-valprint.c: Use string.h, not gdb_string.h.
* charset.c: Use string.h, not gdb_string.h.
* cli-out.c: Use string.h, not gdb_string.h.
* cli/cli-cmds.c: Use string.h, not gdb_string.h.
* cli/cli-decode.c: Use string.h, not gdb_string.h.
* cli/cli-dump.c: Use string.h, not gdb_string.h.
* cli/cli-interp.c: Use string.h, not gdb_string.h.
* cli/cli-logging.c: Use string.h, not gdb_string.h.
* cli/cli-script.c: Use string.h, not gdb_string.h.
* cli/cli-setshow.c: Use string.h, not gdb_string.h.
* cli/cli-utils.c: Use string.h, not gdb_string.h.
* coffread.c: Use string.h, not gdb_string.h.
* common/common-utils.c: Use string.h, not gdb_string.h.
* common/filestuff.c: Use string.h, not gdb_string.h.
* common/linux-procfs.c: Use string.h, not gdb_string.h.
* common/linux-ptrace.c: Use string.h, not gdb_string.h.
* common/signals.c: Use string.h, not gdb_string.h.
* common/vec.h: Use string.h, not gdb_string.h.
* core-regset.c: Use string.h, not gdb_string.h.
* corefile.c: Use string.h, not gdb_string.h.
* corelow.c: Use string.h, not gdb_string.h.
* cp-abi.c: Use string.h, not gdb_string.h.
* cp-support.c: Use string.h, not gdb_string.h.
* cp-valprint.c: Use string.h, not gdb_string.h.
* cris-tdep.c: Use string.h, not gdb_string.h.
* d-lang.c: Use string.h, not gdb_string.h.
* dbxread.c: Use string.h, not gdb_string.h.
* dcache.c: Use string.h, not gdb_string.h.
* demangle.c: Use string.h, not gdb_string.h.
* dicos-tdep.c: Use string.h, not gdb_string.h.
* disasm.c: Use string.h, not gdb_string.h.
* doublest.c: Use string.h, not gdb_string.h.
* dsrec.c: Use string.h, not gdb_string.h.
* dummy-frame.c: Use string.h, not gdb_string.h.
* dwarf2-frame.c: Use string.h, not gdb_string.h.
* dwarf2loc.c: Use string.h, not gdb_string.h.
* dwarf2read.c: Use string.h, not gdb_string.h.
* elfread.c: Use string.h, not gdb_string.h.
* environ.c: Use string.h, not gdb_string.h.
* eval.c: Use string.h, not gdb_string.h.
* event-loop.c: Use string.h, not gdb_string.h.
* exceptions.c: Use string.h, not gdb_string.h.
* exec.c: Use string.h, not gdb_string.h.
* expprint.c: Use string.h, not gdb_string.h.
* f-exp.y: Use string.h, not gdb_string.h.
* f-lang.c: Use string.h, not gdb_string.h.
* f-typeprint.c: Use string.h, not gdb_string.h.
* f-valprint.c: Use string.h, not gdb_string.h.
* fbsd-nat.c: Use string.h, not gdb_string.h.
* findcmd.c: Use string.h, not gdb_string.h.
* findvar.c: Use string.h, not gdb_string.h.
* fork-child.c: Use string.h, not gdb_string.h.
* frame.c: Use string.h, not gdb_string.h.
* frv-linux-tdep.c: Use string.h, not gdb_string.h.
* frv-tdep.c: Use string.h, not gdb_string.h.
* gdb.c: Use string.h, not gdb_string.h.
* gdb_bfd.c: Use string.h, not gdb_string.h.
* gdbarch.c: Use string.h, not gdb_string.h.
* gdbtypes.c: Use string.h, not gdb_string.h.
* gnu-nat.c: Use string.h, not gdb_string.h.
* gnu-v2-abi.c: Use string.h, not gdb_string.h.
* gnu-v3-abi.c: Use string.h, not gdb_string.h.
* go-exp.y: Use string.h, not gdb_string.h.
* go-lang.c: Use string.h, not gdb_string.h.
* go32-nat.c: Use string.h, not gdb_string.h.
* hppa-hpux-tdep.c: Use string.h, not gdb_string.h.
* hppa-linux-nat.c: Use string.h, not gdb_string.h.
* hppanbsd-tdep.c: Use string.h, not gdb_string.h.
* hppaobsd-tdep.c: Use string.h, not gdb_string.h.
* i386-cygwin-tdep.c: Use string.h, not gdb_string.h.
* i386-dicos-tdep.c: Use string.h, not gdb_string.h.
* i386-linux-nat.c: Use string.h, not gdb_string.h.
* i386-linux-tdep.c: Use string.h, not gdb_string.h.
* i386-nto-tdep.c: Use string.h, not gdb_string.h.
* i386-sol2-tdep.c: Use string.h, not gdb_string.h.
* i386-tdep.c: Use string.h, not gdb_string.h.
* i386bsd-tdep.c: Use string.h, not gdb_string.h.
* i386gnu-nat.c: Use string.h, not gdb_string.h.
* i386nbsd-tdep.c: Use string.h, not gdb_string.h.
* i386obsd-tdep.c: Use string.h, not gdb_string.h.
* i387-tdep.c: Use string.h, not gdb_string.h.
* ia64-libunwind-tdep.c: Use string.h, not gdb_string.h.
* ia64-linux-nat.c: Use string.h, not gdb_string.h.
* inf-child.c: Use string.h, not gdb_string.h.
* inf-ptrace.c: Use string.h, not gdb_string.h.
* inf-ttrace.c: Use string.h, not gdb_string.h.
* infcall.c: Use string.h, not gdb_string.h.
* infcmd.c: Use string.h, not gdb_string.h.
* inflow.c: Use string.h, not gdb_string.h.
* infrun.c: Use string.h, not gdb_string.h.
* interps.c: Use string.h, not gdb_string.h.
* iq2000-tdep.c: Use string.h, not gdb_string.h.
* irix5-nat.c: Use string.h, not gdb_string.h.
* jv-exp.y: Use string.h, not gdb_string.h.
* jv-lang.c: Use string.h, not gdb_string.h.
* jv-typeprint.c: Use string.h, not gdb_string.h.
* jv-valprint.c: Use string.h, not gdb_string.h.
* language.c: Use string.h, not gdb_string.h.
* linux-fork.c: Use string.h, not gdb_string.h.
* linux-nat.c: Use string.h, not gdb_string.h.
* lm32-tdep.c: Use string.h, not gdb_string.h.
* m2-exp.y: Use string.h, not gdb_string.h.
* m2-typeprint.c: Use string.h, not gdb_string.h.
* m32c-tdep.c: Use string.h, not gdb_string.h.
* m32r-linux-nat.c: Use string.h, not gdb_string.h.
* m32r-linux-tdep.c: Use string.h, not gdb_string.h.
* m32r-rom.c: Use string.h, not gdb_string.h.
* m32r-tdep.c: Use string.h, not gdb_string.h.
* m68hc11-tdep.c: Use string.h, not gdb_string.h.
* m68k-tdep.c: Use string.h, not gdb_string.h.
* m68kbsd-tdep.c: Use string.h, not gdb_string.h.
* m68klinux-nat.c: Use string.h, not gdb_string.h.
* m68klinux-tdep.c: Use string.h, not gdb_string.h.
* m88k-tdep.c: Use string.h, not gdb_string.h.
* macrocmd.c: Use string.h, not gdb_string.h.
* main.c: Use string.h, not gdb_string.h.
* mdebugread.c: Use string.h, not gdb_string.h.
* mem-break.c: Use string.h, not gdb_string.h.
* memattr.c: Use string.h, not gdb_string.h.
* memory-map.c: Use string.h, not gdb_string.h.
* mep-tdep.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-break.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-disas.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-env.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-stack.c: Use string.h, not gdb_string.h.
* mi/mi-cmd-var.c: Use string.h, not gdb_string.h.
* mi/mi-cmds.c: Use string.h, not gdb_string.h.
* mi/mi-console.c: Use string.h, not gdb_string.h.
* mi/mi-getopt.c: Use string.h, not gdb_string.h.
* mi/mi-interp.c: Use string.h, not gdb_string.h.
* mi/mi-main.c: Use string.h, not gdb_string.h.
* mi/mi-parse.c: Use string.h, not gdb_string.h.
* microblaze-rom.c: Use string.h, not gdb_string.h.
* microblaze-tdep.c: Use string.h, not gdb_string.h.
* mingw-hdep.c: Use string.h, not gdb_string.h.
* minidebug.c: Use string.h, not gdb_string.h.
* minsyms.c: Use string.h, not gdb_string.h.
* mips-irix-tdep.c: Use string.h, not gdb_string.h.
* mips-linux-tdep.c: Use string.h, not gdb_string.h.
* mips-tdep.c: Use string.h, not gdb_string.h.
* mips64obsd-tdep.c: Use string.h, not gdb_string.h.
* mipsnbsd-tdep.c: Use string.h, not gdb_string.h.
* mipsread.c: Use string.h, not gdb_string.h.
* mn10300-linux-tdep.c: Use string.h, not gdb_string.h.
* mn10300-tdep.c: Use string.h, not gdb_string.h.
* monitor.c: Use string.h, not gdb_string.h.
* moxie-tdep.c: Use string.h, not gdb_string.h.
* mt-tdep.c: Use string.h, not gdb_string.h.
* nbsd-tdep.c: Use string.h, not gdb_string.h.
* nios2-linux-tdep.c: Use string.h, not gdb_string.h.
* nto-procfs.c: Use string.h, not gdb_string.h.
* nto-tdep.c: Use string.h, not gdb_string.h.
* objc-lang.c: Use string.h, not gdb_string.h.
* objfiles.c: Use string.h, not gdb_string.h.
* opencl-lang.c: Use string.h, not gdb_string.h.
* osabi.c: Use string.h, not gdb_string.h.
* osdata.c: Use string.h, not gdb_string.h.
* p-exp.y: Use string.h, not gdb_string.h.
* p-lang.c: Use string.h, not gdb_string.h.
* p-typeprint.c: Use string.h, not gdb_string.h.
* parse.c: Use string.h, not gdb_string.h.
* posix-hdep.c: Use string.h, not gdb_string.h.
* ppc-linux-nat.c: Use string.h, not gdb_string.h.
* ppc-sysv-tdep.c: Use string.h, not gdb_string.h.
* ppcfbsd-tdep.c: Use string.h, not gdb_string.h.
* ppcnbsd-tdep.c: Use string.h, not gdb_string.h.
* ppcobsd-tdep.c: Use string.h, not gdb_string.h.
* printcmd.c: Use string.h, not gdb_string.h.
* procfs.c: Use string.h, not gdb_string.h.
* prologue-value.c: Use string.h, not gdb_string.h.
* python/py-auto-load.c: Use string.h, not gdb_string.h.
* python/py-gdb-readline.c: Use string.h, not gdb_string.h.
* ravenscar-thread.c: Use string.h, not gdb_string.h.
* regcache.c: Use string.h, not gdb_string.h.
* registry.c: Use string.h, not gdb_string.h.
* remote-fileio.c: Use string.h, not gdb_string.h.
* remote-m32r-sdi.c: Use string.h, not gdb_string.h.
* remote-mips.c: Use string.h, not gdb_string.h.
* remote-sim.c: Use string.h, not gdb_string.h.
* remote.c: Use string.h, not gdb_string.h.
* reverse.c: Use string.h, not gdb_string.h.
* rs6000-aix-tdep.c: Use string.h, not gdb_string.h.
* ser-base.c: Use string.h, not gdb_string.h.
* ser-go32.c: Use string.h, not gdb_string.h.
* ser-mingw.c: Use string.h, not gdb_string.h.
* ser-pipe.c: Use string.h, not gdb_string.h.
* ser-tcp.c: Use string.h, not gdb_string.h.
* ser-unix.c: Use string.h, not gdb_string.h.
* serial.c: Use string.h, not gdb_string.h.
* sh-tdep.c: Use string.h, not gdb_string.h.
* sh64-tdep.c: Use string.h, not gdb_string.h.
* shnbsd-tdep.c: Use string.h, not gdb_string.h.
* skip.c: Use string.h, not gdb_string.h.
* sol-thread.c: Use string.h, not gdb_string.h.
* solib-dsbt.c: Use string.h, not gdb_string.h.
* solib-frv.c: Use string.h, not gdb_string.h.
* solib-osf.c: Use string.h, not gdb_string.h.
* solib-spu.c: Use string.h, not gdb_string.h.
* solib-target.c: Use string.h, not gdb_string.h.
* solib.c: Use string.h, not gdb_string.h.
* somread.c: Use string.h, not gdb_string.h.
* source.c: Use string.h, not gdb_string.h.
* sparc-nat.c: Use string.h, not gdb_string.h.
* sparc-sol2-tdep.c: Use string.h, not gdb_string.h.
* sparc-tdep.c: Use string.h, not gdb_string.h.
* sparc64-tdep.c: Use string.h, not gdb_string.h.
* sparc64fbsd-tdep.c: Use string.h, not gdb_string.h.
* sparc64nbsd-tdep.c: Use string.h, not gdb_string.h.
* sparcnbsd-tdep.c: Use string.h, not gdb_string.h.
* spu-linux-nat.c: Use string.h, not gdb_string.h.
* spu-multiarch.c: Use string.h, not gdb_string.h.
* spu-tdep.c: Use string.h, not gdb_string.h.
* stabsread.c: Use string.h, not gdb_string.h.
* stack.c: Use string.h, not gdb_string.h.
* std-regs.c: Use string.h, not gdb_string.h.
* symfile.c: Use string.h, not gdb_string.h.
* symmisc.c: Use string.h, not gdb_string.h.
* symtab.c: Use string.h, not gdb_string.h.
* target.c: Use string.h, not gdb_string.h.
* thread.c: Use string.h, not gdb_string.h.
* tilegx-linux-nat.c: Use string.h, not gdb_string.h.
* tilegx-tdep.c: Use string.h, not gdb_string.h.
* top.c: Use string.h, not gdb_string.h.
* tracepoint.c: Use string.h, not gdb_string.h.
* tui/tui-command.c: Use string.h, not gdb_string.h.
* tui/tui-data.c: Use string.h, not gdb_string.h.
* tui/tui-disasm.c: Use string.h, not gdb_string.h.
* tui/tui-file.c: Use string.h, not gdb_string.h.
* tui/tui-layout.c: Use string.h, not gdb_string.h.
* tui/tui-out.c: Use string.h, not gdb_string.h.
* tui/tui-regs.c: Use string.h, not gdb_string.h.
* tui/tui-source.c: Use string.h, not gdb_string.h.
* tui/tui-stack.c: Use string.h, not gdb_string.h.
* tui/tui-win.c: Use string.h, not gdb_string.h.
* tui/tui-windata.c: Use string.h, not gdb_string.h.
* tui/tui-winsource.c: Use string.h, not gdb_string.h.
* typeprint.c: Use string.h, not gdb_string.h.
* ui-file.c: Use string.h, not gdb_string.h.
* ui-out.c: Use string.h, not gdb_string.h.
* user-regs.c: Use string.h, not gdb_string.h.
* utils.c: Use string.h, not gdb_string.h.
* v850-tdep.c: Use string.h, not gdb_string.h.
* valarith.c: Use string.h, not gdb_string.h.
* valops.c: Use string.h, not gdb_string.h.
* valprint.c: Use string.h, not gdb_string.h.
* value.c: Use string.h, not gdb_string.h.
* varobj.c: Use string.h, not gdb_string.h.
* vax-tdep.c: Use string.h, not gdb_string.h.
* vaxnbsd-tdep.c: Use string.h, not gdb_string.h.
* vaxobsd-tdep.c: Use string.h, not gdb_string.h.
* windows-nat.c: Use string.h, not gdb_string.h.
* xcoffread.c: Use string.h, not gdb_string.h.
* xml-support.c: Use string.h, not gdb_string.h.
* xstormy16-tdep.c: Use string.h, not gdb_string.h.
* xtensa-linux-nat.c: Use string.h, not gdb_string.h.
This is to help make it slightly clearer how this method is expected
to extract data from the given register.
gdb/ChangeLog:
* dwarf2expr.h (struct dwarf_expr_context_funcs)
<read_addr_from_reg>: Renames "read_reg".
* dwarf2-frame.c (read_addr_from_reg): Renames "read_reg".
Adjust comment.
(dwarf2_frame_ctx_funcs, execute_stack_op, dwarf2_frame_cache):
Use read_addr_from_reg in place of read_reg.
* dwarf2expr.c (execute_stack_op): Use read_addr_from_reg
in place of read_reg.
* dwarf2loc.c (dwarf_expr_read_addr_from_reg): Renames
dwarf_expr_read_reg.
(dwarf_expr_ctx_funcs): Replace dwarf_expr_read_reg
with dwarf_expr_read_addr_from_reg.
(needs_frame_read_addr_from_reg): Renames needs_frame_read_reg.
(needs_frame_ctx_funcs): Replace needs_frame_read_reg with
needs_frame_read_addr_from_reg.
Similar to qsort(), the glibc version of memcpy() also declares its
arguments with __attribute__(__nonnull__(...)). If NULL is passed
anyway, upstream GCC's new pass '-fisolate-erroneous-paths' typically
causes a trap in such cases. I've encountered this with GDB in
chain_candidate() when trying to execute the break.exp test case.
gdb/
2013-11-13 Andreas Arnez <arnez@linux.vnet.ibm.com>
* dwarf2loc.c (chain_candidate): Prevent invoking memcpy with
NULL.
Consider the following code, compiled at -O2 on ppc-linux:
procedure Increment (Val : in out Float; Msg : String);
The implementation does not really matter in this case). In our example,
this function is being called from a function with Param_1 set to 99.0.
Trying to break inside that function, and running until reaching that
breakpoint yields:
(gdb) b increment
Breakpoint 1 at 0x100014b4: file callee.adb, line 6.
(gdb) run
Starting program: /[...]/foo
Breakpoint 1, callee.increment (val=99.0, val@entry=0.0, msg=...)
at callee.adb:6
6 if Val > 200.0 then
The @entry value for parameter "val" is incorrect, it should be 99.0.
The associated call-site parameter DIE looks like this:
.uleb128 0xc # (DIE (0x115) DW_TAG_GNU_call_site_parameter)
.byte 0x2 # DW_AT_location
.byte 0x90 # DW_OP_regx
.uleb128 0x21
.byte 0x3 # DW_AT_GNU_call_site_value
.byte 0xf5 # DW_OP_GNU_regval_type
.uleb128 0x3f
.uleb128 0x25
The DW_AT_GNU_call_site_value uses a DW_OP_GNU_regval_type
operation, referencing register 0x3f=63, which is $f31,
an 8-byte floating register. In that register, the value is
stored using the usual 8-byte float format:
(gdb) info float
f31 99.0 (raw 0x4058c00000000000)
The current code evaluating DW_OP_GNU_regval_type operations
currently is (dwarf2expr.c:execute_stack_op):
result = (ctx->funcs->read_reg) (ctx->baton, reg);
result_val = value_from_ulongest (address_type, result);
result_val = value_from_contents (type,
value_contents_all (result_val));
What the ctx->funcs->read_reg function does is read the contents
of the register as if it contained an address. The rest of the code
continues that assumption, thinking it's OK to then use that to
create an address/ulongest struct value, which we then re-type
to the type specified by DW_OP_GNU_regval_type.
We're getting 0.0 above because the read_reg implementations
end up treating the contents of the FP register as an integral,
reading only 4 out of the 8 bytes. Being a big-endian target,
we read the high-order ones, which gives us zero.
This patch fixes the problem by introducing a new callback to
read the contents of a register as a given type, and then adjust
the handling of DW_OP_GNU_regval_type to use that new callback.
gdb/ChangeLog:
* dwarf2expr.h (struct dwarf_expr_context_funcs) <read_reg>:
Extend the documentation a bit.
<get_reg_value>: New field.
* dwarf2loc.c (dwarf_expr_get_reg_value)
(needs_frame_get_reg_value): New functions.
(dwarf_expr_ctx_funcs, needs_frame_ctx_funcs): Add "get_reg_value"
callback.
* dwarf2-frame.c (get_reg_value): New function.
(dwarf2_frame_ctx_funcs): Add "get_reg_value" callback.
* dwarf2expr.c (execute_stack_op) <DW_OP_GNU_regval_type>:
Use new callback to compute result_val.
gdb/testsuite/ChangeLog:
* gdb.ada/O2_float_param: New testcase.
Currently, in some scenarios, GDB prints <optimized out> when printing
outer frame registers. An <optimized out> register is a confusing
concept. What this really means is that the register is
call-clobbered, or IOW, not saved by the callee. This patch makes GDB
say that instead.
Before patch:
(gdb) p/x $rax $1 = <optimized out>
(gdb) info registers rax
rax <optimized out>
After patch:
(gdb) p/x $rax
$1 = <not saved>
(gdb) info registers rax
rax <not saved>
However, if for some reason the debug info describes a variable as
being in such a register (**), we still want to print <optimized out>
when printing the variable. IOW, <not saved> is reserved for
inspecting registers at the machine level. The patch uses
lval_register+optimized_out to encode the not saved registers, and
makes it so that optimized out variables always end up in
!lval_register values.
** See <https://sourceware.org/ml/gdb-patches/2012-08/msg00787.html>.
Current/recent enough GCC doesn't mark variables/arguments as being in
call-clobbered registers in the ranges corresponding to function
calls, while older GCCs did. Newer GCCs will just not say where the
variable is, so GDB will end up realizing the variable is optimized
out.
frame_unwind_got_optimized creates not_lval optimized out registers,
so by default, in most cases, we'll see <optimized out>.
value_of_register is the function eval.c uses for evaluating
OP_REGISTER (again, $pc, etc.), and related bits. It isn't used for
anything else. This function makes sure to return lval_register
values. The patch makes "info registers" and the MI equivalent use it
too. I think it just makes a lot of sense, as this makes it so that
when printing machine registers ($pc, etc.), we go through a central
function.
We're likely to need a different encoding at some point, if/when we
support partially saved registers. Even then, I think
value_of_register will still be the spot to tag the intention to print
machine register values differently.
value_from_register however may also return optimized out
lval_register values, so at a couple places where we're computing a
variable's location from a dwarf expression, we convert the resulting
value away from lval_register to a regular optimized out value.
Tested on x86_64 Fedora 17
gdb/
2013-10-02 Pedro Alves <palves@redhat.com>
* cp-valprint.c (cp_print_value_fields): Adjust calls to
val_print_optimized_out.
* jv-valprint.c (java_print_value_fields): Likewise.
* p-valprint.c (pascal_object_print_value_fields): Likewise.
* dwarf2loc.c (dwarf2_evaluate_loc_desc_full)
<DWARF_VALUE_REGISTER>: If the register was not saved, return a
new optimized out value.
* findvar.c (address_from_register): Likewise.
* frame.c (put_frame_register): Tweak error string to say the
register was not saved, rather than optimized out.
* infcmd.c (default_print_one_register_info): Adjust call to
val_print_optimized_out. Use value_of_register instead of
get_frame_register_value.
* mi/mi-main.c (output_register): Use value_of_register instead of
get_frame_register_value.
* valprint.c (valprint_check_validity): Likewise.
(val_print_optimized_out): New value parameter. If the value is
lval_register, print <not saved> instead.
(value_check_printable, val_print_scalar_formatted): Adjust calls
to val_print_optimized_out.
* valprint.h (val_print_optimized_out): New value parameter.
* value.c (struct value) <optimized_out>: Extend comment.
(error_value_optimized_out): New function.
(require_not_optimized_out): Use it. Use a different string for
lval_register values.
* value.h (error_value_optimized_out): New declaration.
* NEWS: Mention <not saved>.
gdb/testsuite/
2013-10-02 Pedro Alves <palves@redhat.com>
* gdb.dwarf2/dw2-reg-undefined.exp <pattern_rax_rbx_rcx_print,
pattern_rax_rbx_rcx_info>: Set to "<not saved>".
* gdb.mi/mi-reg-undefined.exp (opt_out_pattern): Delete.
(not_saved_pattern): New.
Replace use of the former with the latter.
gdb/doc/
2013-10-02 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Registers): Expand description of saved registers
in frames. Explain <not saved>.
A couple years ago, dwarf_expr_fetch used to return a CORE_ADDR. It
was made to return a ULONGEST since, and the 'dwarf_regnum' local
adjusted accordingly, but, we kept printing it with paddress.
gdbarch_dwarf2_reg_to_regnum takes the register number as 'int', so
there's really no point in using ULONGEST/pulongest either.
gdb/
2013-09-05 Pedro Alves <palves@redhat.com>
* dwarf2loc.c (dwarf2_evaluate_loc_desc_full): 'dwarf_regnum'
local is now int instead of ULONGEST. Print it with %d
instead of paddress.
I came across a pattern used to construct a value in the following way:
struct value *val = allocate_value_lazy (type);
VALUE_LVAL (val) = lval_memory;
set_value_address (val, address);
Instead we fold the above call into:
value_at_lazy (type, addr);
2013-08-27 Sanimir Agovic <sanimir.agovic@intel.com>
* dwarf2loc.c (dwarf2_evaluate_loc_desc_full): Use value_at_lazy instead
of assembling value via allocate_value_lazy and attribute setter.
* findvar.c (default_read_var_value): Use value_at_lazy instead of
assembling value via allocate_value_lazy and attribute setter.
* valops.c (do_search_struct_field): Use value_at_lazy instead of
assembling value via allocate_value_lazy and attribute setter.
2013-06-26 Pedro Alves <pedro@codesourcery.com>
Yao Qi <yao@codesourcery.com>
* ctf.c (ctf_traceframe_info): Push trace state variables
present in the trace data into the traceframe info object.
* breakpoint.c (DEF_VEC_I): Remove.
* common/filestuff.c (DEF_VEC_I): Likewise.
* dwarf2loc.c (DEF_VEC_I): Likewise.
* mi/mi-main.c (DEF_VEC_I): Likewise.
* common/gdb_vecs.h (DEF_VEC_I): Define vector for int.
* features/traceframe-info.dtd: Add tvar element and its
attributes.
* tracepoint.c (free_traceframe_info): Free vector 'tvars'.
(build_traceframe_info): Push trace state variables present in the
trace data into the traceframe info object.
(traceframe_info_start_tvar): New function.
(tvar_attributes): New.
(traceframe_info_children): Add "tvar" element.
* tracepoint.h (struct traceframe_info) <tvars>: New field.
* NEWS: Mention the change in GDB and GDBserver.
gdb/doc:
2013-06-26 Pedro Alves <pedro@codesourcery.com>
* gdb.texinfo (Traceframe Info Format): Document tvar element and
its attributes.
gdb/gdbserver:
2013-06-26 Pedro Alves <pedro@codesourcery.com>
* tracepoint.c (build_traceframe_info_xml): Output trace state
variables present in the trace buffer.
PR symtab/15391 is a failure with the DW_OP_GNU_implicit_pointer
feature.
I tracked it down to a logic error in read_pieced_value. The code
truncates this_size_bits according to the type size and offset too
early -- it should do it after taking bits_to_skip into account.
This patch fixes the bug.
While testing this, I also tripped across a latent bug because
indirect_pieced_value does not sign-extend where needed. This patch
fixes this bug as well.
Finally, Pedro pointed out that a previous version implemented sign
extension incorrectly. This version introduces a new gdb_sign_extend
function for this. A couple of notes on this function:
* It has the gdb_ prefix to avoid clashes with various libraries that
felt free to avoid proper namespacing. There is a "sign_extend"
function in a Tile GX header, in an SOM-related BFD header (and in
sh64-tdep.c and as a macro in arm-wince-tdep.c, but those are
ours...)
* I looked at all the sign extensions in gdb and didn't see ones that
I felt comfortable converting to use this function; in large part
because I don't have a good way to test the conversion.
Built and regtested on x86-64 Fedora 18. New test cases included;
this required a minor addition to the DWARF assembler. Note that the
DWARF CU made by implptrpiece.exp uses a funny pointer size in order
to show the sign-extension bug on all platforms.
* dwarf2loc.c (read_pieced_value): Truncate this_size_bits
after taking bits_to_skip into account. Sign extend byte_offset.
* utils.h (gdb_sign_extend): Declare.
* utils.c (gdb_sign_extend): New function.
* gdb.dwarf2/implptrpiece.exp: New file.
* gdb.dwarf2/implptrconst.exp (d): New variable.
Print d.
* lib/dwarf2.exp (Dwarf::_location): Handle DW_OP_piece.
-Wpointer-sign catches all these cases across the codebase that should
be using gdb_byte for raw target bytes. I think these are all
obvious, hence I've collapsed into a single patch.
gdb/
2013-04-19 Pedro Alves <palves@redhat.com>
* aarch64-tdep.c (aarch64_default_breakpoint): Change type to
gdb_byte[].
(aarch64_breakpoint_from_pc): Change return type to gdb_byte *.
* ada-lang.c (ada_value_assign): Use gdb_byte.
* alphanbsd-tdep.c (sigtramp_retcode): Change type to gdb_byte[].
(alphanbsd_sigtramp_offset): Use gdb_byte.
* arm-linux-tdep.c (arm_linux_arm_le_breakpoint)
(arm_linux_arm_be_breakpoint, eabi_linux_arm_le_breakpoint)
(eabi_linux_arm_be_breakpoint, arm_linux_thumb_be_breakpoint)
(arm_linux_thumb_le_breakpoint, arm_linux_thumb2_be_breakpoint)
(arm_linux_thumb2_le_breakpoint): Change type to gdb_byte[].
* arm-tdep.c (arm_stub_unwind_sniffer)
(arm_displaced_init_closure): Use gdb_byte.
(arm_default_arm_le_breakpoint, arm_default_arm_be_breakpoint)
(arm_default_thumb_le_breakpoint)
(arm_default_thumb_be_breakpoint): Change type to gdb_byte[].
* arm-tdep.h (struct gdbarch_tdep) <arm_breakpoint,
thumb_breakpoint, thumb2_breakpoint>: Change type to gdb_byte *.
* arm-wince-tdep.c (arm_wince_le_breakpoint)
(arm_wince_thumb_le_breakpoint): Change type to gdb_byte[].
* armnbsd-tdep.c (arm_nbsd_arm_le_breakpoint)
(arm_nbsd_arm_be_breakpoint, arm_nbsd_thumb_le_breakpoint)
(arm_nbsd_thumb_be_breakpoint): Change type to gdb_byte[].
* armobsd-tdep.c (arm_obsd_thumb_le_breakpoint)
(arm_obsd_thumb_be_breakpoint): Change type to gdb_byte[].
* cris-tdep.c (push_stack_item, cris_push_dummy_call)
(cris_store_return_value, cris_extract_return_value): Use
gdb_byte.
(constraint): Change type of parameter to char * from signed
char*. Use gdb_byte.
* dwarf2loc.c (read_pieced_value, write_pieced_value): Change type
of local buffer to gdb_byte *.
* dwarf2read.c (read_index_from_section): Use gdb_byte.
(create_dwp_hash_table): Change type of locals to gdb_byte *.
(add_address_entry): Change type of local buffer to gdb_byte[].
* frv-tdep.c (frv_adjust_breakpoint_address, find_func_descr)
(frv_push_dummy_call): Use gdb_byte.
* hppa-hpux-tdep.c (hppa_hpux_push_dummy_code)
(hppa_hpux_supply_ss_fpblock, hppa_hpux_supply_ss_wide)
(hppa_hpux_supply_save_state): Use gdb_byte.
* hppa-tdep.c (hppa32_push_dummy_call)
(hppa64_convert_code_addr_to_fptr): Use gdb_byte.
* ia64-tdep.c (extract_bit_field, replace_bit_field)
(slotN_contents, replace_slotN_contents): Change type of parameter
to gdb_byte *.
(fetch_instruction, ia64_pseudo_register_write)
(ia64_register_to_value, ia64_value_to_register)
(ia64_extract_return_value, ia64_store_return_value)
(ia64_push_dummy_call): Use gdb_byte.
* m32c-tdep.c (m32c_return_value): Remove cast.
* m68hc11-tdep.c (m68hc11_pseudo_register_write)
(m68hc11_push_dummy_call, m68hc11_store_return_value): Use
gdb_byte.
* mipsnbsd-tdep.c (mipsnbsd_get_longjmp_target): Use gdb_byte.
* mn10300-tdep.c (mn10300_store_return_value)
(mn10300_breakpoint_from_pc, mn10300_push_dummy_call): Use
gdb_byte.
* moxie-tdep.c (moxie_process_readu): Use gdb_byte.
(moxie_process_record): Remove casts.
* ppc-ravenscar-thread.c (supply_register_at_address)
(ppc_ravenscar_generic_store_registers): Use gdb_byte.
* ravenscar-thread.c (get_running_thread_id): Use gdb_byte.
* remote-m32r-sdi.c (m32r_fetch_register): Use gdb_byte.
* remote-mips.c (mips_xfer_memory): Use gdb_byte.
* remote.c (compare_sections_command): Use gdb_byte.
* score-tdep.c (score7_free_memblock): Change type of parameter to
gdb_byte *.
* sh-tdep.c (sh_justify_value_in_reg): Change return type to
gdb_byte *. Use gdb_byte.
(sh_push_dummy_call_fpu): Use gdb_byte.
(sh_extract_return_value_nofpu, sh_extract_return_value_fpu)
(sh_store_return_value_nofpu, sh_store_return_value_fpu)
(sh_register_convert_to_virtual, sh_register_convert_to_raw):
Change parameter type to 'gdb_byte *'. Use gdb_byte.
(sh_pseudo_register_read, sh_pseudo_register_write): Use gdb_byte.
* sh64-tdep.c (sh64_push_dummy_call): Use gdb_byte.
(sh64_store_return_value, sh64_register_convert_to_virtual):
Change parameter type to 'gdb_byte *'. Use gdb_byte.
(sh64_pseudo_register_write): Use gdb_byte.
* solib-darwin.c (darwin_current_sos): Add casts to 'gdb_byte *'.
* solib-irix.c (fetch_lm_info): Likewise. Use gdb_byte for byte
buffer.
(irix_current_sos): Use gdb_byte.
* solib-som.c (som_current_sos): Use gdb_byte.
* sparc-ravenscar-thread.c (supply_register_at_address)
(sparc_ravenscar_generic_store_registers): Use gdb_byte.
* spu-multiarch.c (spu_xfer_partial): Add cast to 'char *'.
* spu-tdep.c (spu_get_overlay_table): Use gdb_byte.
* tic6x-tdep.c (tic6x_breakpoint_from_pc): Change return type to
'gdb_byte *'.
* tic6x-tdep.h (struct gdbarch_tdep) <breakpoint>: Change type to
'gdb_byte *'.
* tracepoint.c (tfile_fetch_registers): Use gdb_byte.
* xstormy16-tdep.c (xstormy16_extract_return_value)
(xstormy16_store_return_value): Change parameter type to
'gdb_byte *'. Adjust.
(xstormy16_push_dummy_call): Use gdb_byte.
* xtensa-tdep.c (xtensa_scan_prologue, call0_ret)
(call0_analyze_prologue, execute_code): Use gdb_byte.
Hui Zhu <hui@codesourcery.com>
* dwarf2loc.c (access_memory): Change nbits to nbytes in gdb_assert.
(dwarf2_compile_expr_to_ax): Call access_memory in DW_OP_deref and
DW_OP_deref_size.
Fix entry-values in C++ across CUs.
* dwarf2loc.c (call_site_to_target_addr) <FIELD_LOC_KIND_PHYSNAME>: Use
lookup_minimal_symbol. Add a comment.
* dwarf2read.c
(read_call_site_scope) <is_ref_attr> <die_is_declaration>: Prefer
DW_AT_linkage_name.
gdb/testsuite/
Fix entry-values in C++ across CUs.
* gdb.arch/amd64-tailcall-cxx.exp: New file.
* gdb.arch/amd64-tailcall-cxx1.S: New file.
* gdb.arch/amd64-tailcall-cxx1.cc: New file.
* gdb.arch/amd64-tailcall-cxx2.S: New file.
* gdb.arch/amd64-tailcall-cxx2.cc: New file.
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.
SIZE to size_t.
(dwarf2_evaluate_loc_desc): Likewise.
(dwarf2_loc_desc_needs_frame): Likewise.
(locexpr_describe_location_1): Likewise.
* dwarf2loc.h (struct dwarf2_locexpr_baton): Make SIZE as
size_t.
(struct dwarf2_loclist_baton): Likewise.
* dwarf2read.c (struct dwarf_block): Likewise.
(dump_die_shallow): Use pulongest to print dwarf_block.size.
(decode_locdesc): Expand SIZE and I to size_t.
Adjust address for DW_OP_GNU_addr_index.
* dwarf2expr.h (dwarf_expr_context): Update comment.
* dwarf2loc.c (locexpr_describe_location_piece): New arg per_cu,
all callers updated. Handle TLS vars described with
DW_OP_GNU_const_index.
(disassemble_dwarf_expression): Handle DW_OP_GNU_addr_index
and DW_OP_GNU_const_index.
* dwarf2read.c (decode_locdesc): Handle DW_OP_GNU_addr_index.
* dwarf2expr.c (execute_stack_op): Support DW_OP_GNU_parameter_ref.
* dwarf2loc.c (call_site_parameter_matches): Support
CALL_SITE_PARAMETER_PARAM_OFFSET.
(needs_dwarf_reg_entry_value): Push stub value.
* dwarf2read.c (read_call_site_scope): New variable origin. Support
CALL_SITE_PARAMETER_PARAM_OFFSET and its DW_AT_abstract_origin.
* gdbtypes.h (enum call_site_parameter_kind): New item
CALL_SITE_PARAMETER_PARAM_OFFSET.
(struct call_site.parameter.u): New field param_offset.
gdb/testsuite/
* gdb.arch/amd64-entry-value-param.S: New file.
* gdb.arch/amd64-entry-value-param.c: New file.
* gdb.arch/amd64-entry-value-param.exp: New file.
Code cleanup: Generalize call_site.parameter key.
* dwarf2expr.c (execute_stack_op) <DW_OP_GNU_entry_value>: Remove
variable dwarf_reg. New variable kind_u. Update parameters to
push_dwarf_reg_entry_value.
(ctx_no_push_dwarf_reg_entry_value): Update parameters.
* dwarf2expr.h (enum call_site_parameter_kind)
(union call_site_parameter_u): Forward declarations.
(struct dwarf_expr_context_funcs): Update parameters and their
description for push_dwarf_reg_entry_value.
(ctx_no_push_dwarf_reg_entry_value): Update parameters.
* dwarf2loc.c (call_site_parameter_matches): New function.
(dwarf_expr_reg_to_entry_parameter): Update parameters and their
description. Use call_site_parameter_matches.
(dwarf_expr_push_dwarf_reg_entry_value, value_of_dwarf_reg_entry):
Update parameters and their description.
(value_of_dwarf_block_entry): Remove variables dwarf_reg and fb_offset.
New variable kind_u. Adjust the caller for updated parameters.
(needs_dwarf_reg_entry_value): Update parameters.
* dwarf2read.c (read_call_site_scope): New variable loc. Use it
instead of attr. Update for the changed fields of struct
call_site_parameter.
* gdbtypes.h: Include dwarf2expr.h.
(enum call_site_parameter_kind): New.
(struct call_site.parameter): New field kind. Wrap dwarf_reg and
fb_offset into new union u.
"const gdb_byte *".
(struct dwarf2_fde): Make instructions, end "const gdb_byte *".
(execute_cfa_program): Update to match API of leb128 functions.
(read_1_byte, read_4_bytes, read_8_bytes): Make buf parameter
"const gdb_byte *".
(read_unsigned_leb128, read_signed_leb128): Delete.
(read_initial_length): Change type of buf argument to
"const gdb_byte *".
(read_encoded_value): Update to match API of leb128 functions.
(decode_frame_entry): Change result to "const gdb_byte *", and
similarly for "start" parameter.
(decode_frame_entry_1): Ditto. Use new leb128 reader functions.
(dwarf2_build_frame_info): Change local frame_ptr to
"const gdb_byte *".
* dwarf2expr.c (safe_read_uleb128, safe_read_sleb128): Replaces
read_uleb128, read_sleb128. All callers updated.
(safe_skip_leb128): New function.
(dwarf_block_to_dwarf_reg): Update to match API of leb128 functions.
Call gdb_read_uleb128, gdb_skip_leb128 instead of read_uleb128.
(dwarf_block_to_dwarf_reg_deref): Update to match API of leb128
functions. Call gdb_read_uleb128, gdb_read_sleb128 instead of
read_uleb128, read_sleb128.
(dwarf_block_to_fb_offset, dwarf_block_to_sp_offset): Ditto.
(execute_stack_op): Update to match API of leb128 functions.
* dwarf2expr.h: #include "leb128.h".
(read_uleb128, read_sleb128): Delete.
(gdb_read_uleb128, gdb_read_sleb128, gdb_skip_leb128): New functions.
(safe_read_uleb128, safe_read_sleb128, safe_skip_leb128): Declare.
* dwarf2loc.c (debug_loc_kind): New enum.
(decode_debug_loc_addresses): New function.
(decode_debug_loc_dwo_addresses): New function.
(dwarf2_find_location_expression): Rewrite.
(dwarf2_compile_expr_to_ax): Update to match API of leb128 functions.
(locexpr_describe_location_piece): Ditto.
(disassemble_dwarf_expression): Ditto.
(locexpr_describe_location_1): Ditto.
(loclist_describe_location): Rewrite.
* dwarf2loc.h (dwarf2_loclist_baton): New member "from_dwo".
* dwarf2read.c (die_reader_specs): New member "buffer_end".
(dwarf2_section_buffer_overflow_complaint): Renamed from
dwarf2_macros_too_long_complaint. All callers updated.
(skip_leb128): Delete.
(init_cu_die_reader): Initialize reader->buffer_end.
(skip_one_die): Replace call to skip_leb128 with safe_skip_leb128.
(skip_form_bytes): New arg buffer_end. All callers updated.
Replace call to skip_leb128 with gdb_skip_leb128.
(skip_unknown_opcode): New arg mac_end. All callers updated.
(fill_in_loclist_baton): Initialize baton->from_dwo.
* symfile.c (default_symfile_relocate): Use sectp->owner instead of
objfile->obfd.
* symfile.h (dwarf2_debug_sections): New member addr.
* dwarf2expr.c (execute_stack_op): New case DW_OP_GNU_addr_index.
(ctx_no_get_addr_index): New function.
* dwarf2expr.h (dwarf_expr_context_funcs): New member get_addr_index.
(ctx_no_get_addr_index): Declare.
* dwarf2-frame.c (dwarf2_frame_ctx_funcs): Update.
* dwarf2loc.c (dwarf_expr_get_addr_index): New function.
(dwarf_expr_ctx_funcs): Update.
(needs_get_addr_index): New function.
(needs_frame_ctx_funcs): Update.
* dwarf2loc.h (dwarf2_read_addr_index): Declare.
* dwarf2read.c: #include "gdbcore.h".
(dwarf2_per_objfile): New members addr, dwo_files.
(dwarf2_elf_names): Add entry for addr.
(struct dwo_section_names): New type.
(dwo_section_names): New static global.
(dwarf2_cu): New members dwo_unit, addr_base, have_addr_base.
(dwarf2_per_cu_data): New member is_debug_types, all boolean uses of
old debug_types_section member updated to use this.
Rename member debug_types_section to info_or_types_section,
all uses updated.
(signatured_type): Rename member type_offset to type_offset_in_tu,
all uses updated. New member type_offset_in_section.
(struct dwo_sections): New type.
(struct dwo_unit): New type.
(struct dwo_file): New type.
(die_reader_specs): New member dwo_file.
(dwarf2_locate_sections): Watch for .debug_addr.
(zlib_decompress_section): Use sectp->owner instead of objfile->obfd.
(dwarf2_read_section): Get bfd of section from bfd's asection,
instead of objfile.
(create_cus_from_index): Initialize the_cu->info_or_types_section.
(create_signatured_type_table_from_index): Initialize
sig_type->info_or_types_section.
(dw2_get_file_names): Statement lists for type units with DWO files
live in the DWO file.
(create_debug_types_hash_table): New function.
(create_all_type_units): Rewrite.
(init_cu_die_reader): New arg dwo_file, all callers updated.
(init_and_read_dies_worker): Get section from
this_cu->info_or_types_section. Set sig_type->type_offset_in_section.
Watch for DW_AT_GNU_dwo_name and if present lookup the file and
continue reading the CU/TU from there.
(init_cutu_and_read_dies_no_follow): New arg dwo_file, all callers
updated. Get section from this_cu->info_or_types_section.
(create_all_comp_units): Initialize this_cu->info_or_types_section.
(skip_one_die): New cases DW_FORM_GNU_addr_index,
DW_FORM_GNU_str_index.
(hash_dwo_file, eq_dwo_file): New functions.
(allocate_dwo_file_hash_table): New function.
(hash_dwo_unit, eq_dwo_unit): New functions.
(allocate_dwo_unit_table): New function.
(dwarf2_locate_dwo_sections): New function.
(struct create_dwo_info_table_data): New type.
(create_debug_info_hash_table_reader): New function.
(create_debug_info_hash_table): New function.
(try_open_dwo_file, open_dwo_file, init_dwo_file): New function.
(lookup_dwo_file): New function.
(lookup_dwo_comp_unit, lookup_dwo_type_unit): New functions.
(free_dwo_file, free_dwo_file_cleanup): New functions.
(free_dwo_file_from_slot, free_dwo_files): New functions.
(dwarf2_get_pc_bounds): Handle DW_FORM_GNU_addr_index.
(dwarf2_record_block_ranges): Ditto.
(read_partial_die): Ditto.
(process_enumeration_scope): Update to use type_offset_in_section.
(read_full_die_1): New function.
(read_full_die): Rewrite.
(read_attribute_value): New cases DW_FORM_GNU_addr_index,
DW_FORM_GNU_str_index.
(read_addr_index_1, read_addr_index): New functions.
(read_addr_index_from_leb128): New function.
(struct dwarf2_read_addr_index_data): New type.
(dwarf2_read_addr_index_reader): New function.
(dwarf2_read_addr_index): New function.
(read_str_index): New function.
(leb128_size): New function.
(dwarf_decode_line_header): Delete arg abfd, all callers updated.
If processing a type unit from a DWO file, get the line section
from the DWO file.
(var_decode_location): Watch for DW_OP_GNU_addr_index.
(dwarf2_const_value_attr): New cases DW_FORM_GNU_addr_index,
DW_FORM_GNU_str_index.
(lookup_die_type): Check whether section offset of type's die is
known before looking it up. Remove assert. Condition can
legimately happen for inter-cu type references.
(dwarf_attr_name): Handle Fission attributes.
(dwarf_form_name): Handle Fission forms.
(dump_die_shallow): New cases DW_FORM_GNU_addr_index,
DW_FORM_GNU_str_index.
(follow_die_sig): Update to use type_offset_in_section.
(decode_locdesc): New case DW_OP_GNU_addr_index.
(skip_form_bytes): New cases DW_FORM_GNU_addr_index,
DW_FORM_GNU_str_index.
(cu_debug_loc_section): New function.
(fill_in_loclist_baton, dwarf2_symbol_mark_computed): Call it.
(dwarf2_per_objfile_free): Unmap .debug_addr section.
Free DWO files if present.
* xcoffread.c (dwarf2_xcoff_names): Add .debug_addr.
testsuite/
* gdb.dwarf2/dw2-intercu.S (.Ltype_int2_in_cu2): Renamed from
.Ltype_int_in_cu2. Use name "int2" instead of "int".
All uses updated.
* gdb.dwarf2/dw2-intercu.exp: Add "ptype int2" ahead of
"ptype func_cu1" to expand cu2 before cu1.
Fix empty DWARF expressions DATA vs. SIZE conditionals.
* dwarf2loc.c (dwarf2_find_location_expression): Clear *LOCEXPR_LENGTH.
(dwarf_expr_frame_base_1): Indicate unavailability via zero *LENGTH.
(locexpr_tracepoint_var_ref): Check only zero SIZE, not zero DATA.
(loclist_read_variable, loclist_tracepoint_var_ref): Do not check for
zero DATA.
* dwarf2loc.h (struct dwarf2_locexpr_baton): Comment DATA vs. SIZE
validity.
* dwarf2read.c (struct dwarf_block): Comment DATA validity.
(dwarf2_fetch_die_location_block, dwarf2_symbol_mark_computed): Do not
clear DATA on zero SIZE.
gdb/testsuite/
Fix empty DWARF expressions DATA vs. SIZE conditionals.
* gdb.dwarf2/dw2-op-call.S (arraycallnoloc, arraynoloc): New DIEs.
(loclist): New.
(4): New abbrev.
* gdb.dwarf2/dw2-op-call.exp: Remove variable srcfile and executable.
Use prepare_for_testing, remove clean_restart.
(p arraynoloc, p arraycallnoloc): New tests.
Display @entry parameter values even for references.
* ada-valprint.c (ada_val_print_1) <TYPE_CODE_REF>: Try also
coerce_ref_if_computed.
* c-valprint.c (c_val_print) <TYPE_CODE_REF>: Likewise.
* dwarf2expr.c (dwarf_block_to_dwarf_reg_deref): New function.
(execute_stack_op) <DW_OP_GNU_entry_value>: Add -1 deref_size to the
existing push_dwarf_reg_entry_value call. Add new detection calling
dwarf_block_to_dwarf_reg_deref. Update the error message.
(ctx_no_push_dwarf_reg_entry_value): New parameter deref_size.
* dwarf2expr.h
(struct dwarf_expr_context_funcs) <push_dwarf_reg_entry_value>: Add new
parameter deref_size, describe it in the comment.
(ctx_no_push_dwarf_reg_entry_value): Add new parameter deref_size.
(dwarf_block_to_dwarf_reg_deref): New declaration.
* dwarf2loc.c (dwarf_entry_parameter_to_value): Add new parameter
deref_size, describe it in the function comment. New variables
data_src and size, fetch the alternative block accoring to DEREF_SIZE.
(dwarf_expr_push_dwarf_reg_entry_value): Add new parameter deref_size,
describe it in the function comment. Fetch the alternative block
accoring to DEREF_SIZE.
(entry_data_value_coerce_ref, entry_data_value_copy_closure)
(entry_data_value_free_closure, entry_data_value_funcs): New.
(value_of_dwarf_reg_entry): New variables checked_type, target_type,
outer_val, target_val, val and addr. Try to fetch and create also
referenced value content.
(pieced_value_funcs): NULL value for coerce_ref.
(needs_dwarf_reg_entry_value): Add new parameter deref_size.
* f-valprint.c (f_val_print) <TYPE_CODE_REF>: Try also
coerce_ref_if_computed.
* opencl-lang.c (opencl_value_funcs): NULL value for coerce_ref.
* p-valprint.c (pascal_val_print) <TYPE_CODE_REF>: Likewise.
* stack.c (read_frame_arg): Compare also dereferenced values.
* value.c (value_computed_funcs): Make the parameter v const, use
value_lval_const for it.
(value_lval_const, coerce_ref_if_computed): New function.
(coerce_ref): New variable retval. Call also coerce_ref_if_computed.
* value.h (struct lval_funcs): New field coerce_ref.
(value_computed_funcs): Make the parameter v const.
(value_lval_const, coerce_ref_if_computed): New declarations.
gdb/testsuite/
Display @entry parameter values even for references.
* gdb.arch/amd64-entry-value.cc (reference, datap, datap_input): New
functions.
(main): New variables regvar, nodatavarp, stackvar1, stackvar2. Call
reference and datap_input.
* gdb.arch/amd64-entry-value.exp (reference, breakhere_reference): New
breakpoints.
(continue to breakpoint: entry_reference: reference)
(entry_reference: bt at entry)
(continue to breakpoint: entry_reference: breakhere_reference)
(entry_reference: bt, entry_reference: ptype regparam)
(entry_reference: p regparam, entry_reference: ptype regparam@entry)
(entry_reference: p regparam@entry, entry_reference: p ®param@entry)
(entry_reference: p regcopy, entry_reference: p nodataparam)
(entry_reference: p nodataparam@entry): New tests.
Display @entry parameter values (without references).
* dwarf2expr.c (dwarf_block_to_fb_offset, dwarf_block_to_sp_offset):
New functions.
* dwarf2expr.h (dwarf_block_to_fb_offset, dwarf_block_to_sp_offset):
New declarations.
* dwarf2loc.c (dwarf2_find_location_expression): Support location list
entry record.
(dwarf_entry_parameter_to_value, value_of_dwarf_reg_entry)
(value_of_dwarf_block_entry, locexpr_read_variable_at_entry): New
functions.
(dwarf2_locexpr_funcs): Install locexpr_read_variable_at_entry.
(loclist_read_variable_at_entry): New function.
(dwarf2_loclist_funcs): Install loclist_read_variable_at_entry.
* dwarf2read.c (read_call_site_scope): Support also DW_OP_fbreg in
DW_AT_location, call dwarf_block_to_sp_offset for it.
* frame.h (print_entry_values_no, print_entry_values_only)
(print_entry_values_preferred, print_entry_values_if_needed)
(print_entry_values_both, print_entry_values_compact)
(print_entry_values_default, print_entry_values): New declarations.
(struct frame_arg): New field entry_kind.
(read_frame_arg): New parameter entryargp.
* mi/mi-cmd-stack.c (list_arg_or_local): New gdb_assert for
arg->entry_kind. Optionally print the `@entry' suffix.
(list_args_or_locals): New variable entryarg, initialize it.
Initialize also entry_kind of arg and entryarg. Conditionalize
list_arg_or_local for arg, add list_arg_or_local for entryarg. Call
xfree for entryarg.error.
* stack.c (print_entry_values_no, print_entry_values_only)
(print_entry_values_preferred, print_entry_values_if_needed)
(print_entry_values_both, print_entry_values_compact)
(print_entry_values_default, print_entry_values_choices)
(print_entry_values): New variables.
(print_frame_arg): New gdb_assert for arg->entry_kind. Optionally
print the `@entry' suffix, possibly in combination for
print_entry_values_compact.
(read_frame_arg): New parameter entryargp, new variables entryval,
entryval_error and val_equal. Read in also entryargp, respect
print_entry_values, compare the values using val_equal, fill in also
argp->entry_kind (together with entryargp->entry_kind).
(print_frame_args): New variable entryarg, initialize it.
Conditionalize print_frame_arg for arg, add print_frame_arg for
entryarg. Call xfree for entryarg.error.
(_initialize_stack): Call add_setshow_enum_cmd for `entry-values'.
* symtab.h (struct symbol_computed_ops): New field
read_variable_at_entry.
gdb/doc/
Display @entry parameter values (without references).
* gdb.texinfo (Tail Call Frames): Add anchor. Add self tail call
example.
(Print Settings): New description of set print entry-values and show
print entry-values.
gdb/testsuite/
Display @entry parameter values (without references).
* gdb.arch/amd64-entry-value.cc (locexpr, stacktest, data, data2)
(different, validity, invalid): New functions.
(main): Call them.
* gdb.arch/amd64-entry-value.exp: New breakpoints breakhere_locexpr,
stacktest, breakhere_stacktest, different, breakhere_different,
breakhere_validity and breakhere_invalid.
(entry: bt): Update for @entry.
(entry_locexpr: *, entry_stack: *, entry_equal: *, entry_different: *)
(entry_validity: *, entry_invalid: *): Many new tests.
* gdb.base/break.exp
(run until breakpoint set at small function, optimized file): Accept
also the @entry suffix.
* gdb.mi/Makefile.in (PROGS): Add mi2-amd64-entry-value.
* gdb.mi/mi2-amd64-entry-value.c: New files.
* gdb.mi/mi2-amd64-entry-value.exp: New files.
Implement basic support for DW_TAG_GNU_call_site.
* block.c: Include gdbtypes.h and exceptions.h.
(call_site_for_pc): New function.
* block.h (call_site_for_pc): New declaration.
* defs.h: Include hashtab.h.
(make_cleanup_htab_delete, core_addr_hash, core_addr_eq): New
declarations.
* dwarf2-frame.c (dwarf2_frame_ctx_funcs): Install
ctx_no_push_dwarf_reg_entry_value.
* dwarf2expr.c (read_uleb128, read_sleb128): Support R as NULL.
(dwarf_block_to_dwarf_reg): New function.
(execute_stack_op) <DW_OP_GNU_entry_value>: Implement it.
(ctx_no_push_dwarf_reg_entry_value): New function.
* dwarf2expr.h (struct dwarf_expr_context_funcs): New field
push_dwarf_reg_entry_value.
(ctx_no_push_dwarf_reg_entry_value, dwarf_block_to_dwarf_reg): New
declarations.
* dwarf2loc.c: Include gdbcmd.h.
(dwarf_expr_ctx_funcs): New forward declaration.
(entry_values_debug, show_entry_values_debug, call_site_to_target_addr)
(dwarf_expr_reg_to_entry_parameter)
(dwarf_expr_push_dwarf_reg_entry_value): New.
(dwarf_expr_ctx_funcs): Install dwarf_expr_push_dwarf_reg_entry_value.
(dwarf2_evaluate_loc_desc_full): Handle NO_ENTRY_VALUE_ERROR.
(needs_dwarf_reg_entry_value): New function.
(needs_frame_ctx_funcs): Install it.
(_initialize_dwarf2loc): New function.
* dwarf2loc.h (entry_values_debug): New declaration.
* dwarf2read.c (struct dwarf2_cu): New field call_site_htab.
(read_call_site_scope): New forward declaration.
(process_full_comp_unit): Copy call_site_htab.
(process_die): Support DW_TAG_GNU_call_site.
(read_call_site_scope): New function.
(dwarf2_get_pc_bounds): Support NULL HIGHPC.
(dwarf_tag_name): Support DW_TAG_GNU_call_site.
(cleanup_htab): Delete.
(write_psymtabs_to_index): Use make_cleanup_htab_delete instead of it.
* exceptions.h (enum errors): New NO_ENTRY_VALUE_ERROR.
* gdb-gdb.py (StructMainTypePrettyPrinter): Support
FIELD_LOC_KIND_DWARF_BLOCK.
* gdbtypes.h (enum field_loc_kind): New entry
FIELD_LOC_KIND_DWARF_BLOCK.
(struct main_type): New loc entry dwarf_block.
(struct call_site, FIELD_DWARF_BLOCK, SET_FIELD_DWARF_BLOCK)
(TYPE_FIELD_DWARF_BLOCK): New.
* python/py-type.c: Include dwarf2loc.h.
(check_types_equal): Support FIELD_LOC_KIND_DWARF_BLOCK. New
internal_error call on unknown FIELD_LOC_KIND.
* symtab.h (struct symtab): New field call_site_htab.
* utils.c (do_htab_delete_cleanup, make_cleanup_htab_delete)
(core_addr_hash, core_addr_eq): New functions.
gdb/testsuite/
Implement basic support for DW_TAG_GNU_call_site.
* gdb.arch/Makefile.in (EXECUTABLES): Add amd64-entry-value.
* gdb.arch/amd64-entry-value.cc: New file.
* gdb.arch/amd64-entry-value.exp: New file.
Remove excessive DWARF expressions memory duplication.
* dwarf2loc.c (per_cu_dwarf_call): Remove variable back_to and its use
for block.data.
(indirect_pieced_value): Remove variable result. Remove variable
back_to and its use for baton.data.
(dwarf2_compile_expr_to_ax): Remove variable back_to and its use for
block.data.
* dwarf2read.c (dwarf2_fetch_die_location_block): Remove xmemdup.
Update the function comment.
Fix implicit pointer offsets.
* dwarf2loc.c (indirect_pieced_value): Comment byte_offset. Use also
ptr.OFFSET.
gdb/testsuite/
Fix implicit pointer offsets.
* gdb.dwarf2/implptr.c (add): New marker baz breakpoint.
* gdb.dwarf2/implptr.exp (set baz breakpoint for implptr)
(continue to breakpoint: continue to baz breakpoint for implptr)
(sanity check element 0, sanity check element 1)
(enter the inlined function, check element 0 for the offset)
(check element 1 for the offset)
(continue to breakpoint: ignore the second baz breakpoint): New tests.
(set foo breakpoint for implptr): Update the breakpoint number.
Fix crash if referenced CU is aged out.
* dwarf2loc.c (per_cu_dwarf_call): New variable back_to, use to for
xfree of block.data.
(indirect_pieced_value): New variable back_to, use to for xfree of
baton.data.
(dwarf2_compile_expr_to_ax): New variable back_to, use to for xfree of
block.data.
* dwarf2read.c (dwarf2_find_base_address): New prototype.
(load_cu): New function from ...
(dw2_do_instantiate_symtab): ... the code here ...
(process_full_comp_unit): ... and here.
(dwarf2_fetch_die_location_block): Call load_cu first. Call xmemdup on
retval.data.
gdb/testsuite/
Fix crash if referenced CU is aged out.
* gdb.dwarf2/dw2-op-call.exp (maintenance set dwarf2 max-cache-age 0):
New.
* gdb.dwarf2/implptr.exp: Likewise.
* dwarf2loc.c (indirect_pieced_value): Use check_typedef for VALUE's
type.
gdb/testsuite/
* gdb.dwarf2/implptr.S: Rebuilt.
* gdb.dwarf2/implptr.c (intp, intpp, intppp): New typedefs.
(bar): Use them for j, k, l.
* gdb.dwarf2/implptr.exp: New variable opts. Support runtest parameter
COMPILE.
(print j in implptr:bar): Update for the intp typedef.
(print p[0].x in implptr:foo): Use more exact regex.
Code cleanup making also optimized out values lazy.
* dwarf2loc.c (dwarf2_evaluate_loc_desc_full): Use
allocate_optimized_out_value. Twice.
(loclist_read_variable) Use allocate_optimized_out_value. Once.
* findvar.c (read_var_value): Likewise.
* value.c (allocate_optimized_out_value): New function.
* value.h (allocate_optimized_out_value): New declaration.
* dwarf2loc.c (read_pieced_value): Handle get_frame_register_bytes
returning that the register piece is unavailable/optimized out.
(write_pieced_value): Handle get_frame_register_bytes returning
that the register piece is unavailable/optimized out when doing a
read-modify write of a bitfield.
* findvar.c (value_from_register): Handle get_frame_register_bytes
returning that the register piece is unavailable/optimized out.
* frame.c (get_frame_register_bytes): New parameters `optimizedp'
and `unavailablep'. Throw error on bad debug info. Use
frame_register instead of frame_register_read, to fill in the new
arguments.
* frame.h (get_frame_register_bytes): New parameters `optimizedp'
and `unavailablep'.
* valops.c: (value_assign): Adjust, and handle
get_frame_register_bytes failing.
* spu-tdep.c: Include exceptions.h.
(spu_software_single_step): Adjust, and handle
get_frame_register_bytes failing.
(spu_get_longjmp_target): Ditto.
* gdbarch.sh (register_to_value): Change to return int. New
parameters `optimizedp' and `unavailablep'.
* gdbarch.h, gdbarch.c: Regenerate.
* i386-tdep.c (i386_register_to_value): Adjust to new
gdbarch_register_to_value interface.
* i387-tdep.c (i387_register_to_value): Ditto.
* i387-tdep.h (i387_register_to_value): Ditto.
* alpha-tdep.c (alpha_register_to_value): Ditto.
* ia64-tdep.c (ia64_register_to_value): Ditto.
* m68k-tdep.c (m68k_register_to_value): Ditto.
* mips-tdep.c (mips_register_to_value): Ditto.
* rs6000-tdep.c (rs6000_register_to_value): Ditto.
* dwarf2loc.c (disassemble_dwarf_expression) <DW_OP_breg[0-9]+>: Use
L and plongest.
(disassemble_dwarf_expression) <DW_OP_bregx>: Drop variable offset,
use L and plongest.
(disassemble_dwarf_expression) <DW_OP_fbreg>: Use L and plongest.
Maciej W. Rozycki
Victor Kamensky
Gary Benson
Pedro Alves
Joel Brobecker
Jan Kratochvil
Tom Tromey
Siva Chandra
Ulrich Weigand
Sanimir Agovic
Andrew Burgess
Andreas Arnez
Sanimir Agovic
Yao Qi
Hui Zhu
Aleksandar Ristovski
Doug Evans
Joel Brobecker
Tristan Gingold
Siddhesh Poyarekar
Sergio Durigan Junior
Michael Snyder