Summary:
The directory_count and file_name_count fields are (section 6.2.4 of
DWARF5 spec) supposed to be uleb128s, not bytes. This bug meant that it
was not possible to correctly parse headers with more than 128 files or
directories.
I've found this bug by code inspection, though the limit is so small
someone would have run into it for real sooner or later. I've verified
that the producer side handles many files correctly, and that we are
able to parse such files after this fix.
Reviewers: dblaikie, jhenderson
Subscribers: aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76498
Summary:
1. FileLineInfoSpecifier::Default isn't the default for anything.
Rename to RawValue, which accurately reflects its role.
2. Most functions that take a part of a FileLineInfoSpecifier end up
constructing a full one later or plumb two values through. Make them
all just take a complete FileLineInfoSpecifier.
3. Printing basenames only was handled differently from all other
variants, make it parallel to all the other variants.
Reviewers: jhenderson
Subscribers: hiraditya, MaskRay, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76394
If the minimum_instruction_length of a debug line program is 0, no
address advancing via special opcodes, DW_LNS_const_add_pc, and
DW_LNS_advance_pc can occur, since the minimum_instruction_length is
used in a multiplication. This patch adds a warning reporting when this
issue occurs.
Reviewed by: probinson
Differential Revision: https://reviews.llvm.org/D75189
The line_range value of a debug line program header is used in divisions
related to special opcodes and DW_LNS_const_add_pc opcodes. As such, a
value of 0 cannot be used. This change introduces a new warning, if such
a situation is identified, and does not perform the relevant
calculations.
Reviewed by: probinson, aprantl
Differential Revision: https://reviews.llvm.org/D43470
This patch adds a check which reports an unsupported value of the
maximum_operations_per_instruction field in a debug line table header.
This is reported once per line table, at most, and only if the tablet
would otherwise need to use it (i.e. never for tables with version 3 or
less, or for tables which don't use DW_LNS_const_add_pc or special
opcodes). Unsupported values are currently any apart from 1.
Reviewed by: probinson, MaskRay
Differential Revision: https://reviews.llvm.org/D74819
The patch was reverted in 69da40033 because of test failures on windows.
The problem was the unpredictable order of some of the error messages,
which I've tried to strenghten in that patch.
It turns out this is not possible to do in verbose mode because there
the data is being writted as it is being parsed. No amount of flushing
(as I've done in the non-verbose mode) will help that. Indeed, even
without any buffering the warning messages can end in the middle of a
line in non-verbose mode.
In this patch, I have reverted the changes which tested the relative
position of the warning message, except for the messages about
unsupported initial length, which are the ones I really wanted to test,
and which do come out reasonably.
The original commit message was:
This patch if motivated by D74560, specifically the subthread about what
to print upon encountering reserved initial length values.
If the debug_line prologue has an unsupported version, we skip parsing
the rest of the data. If we encounter an reserved initial length field,
we don't even parse the version. However, we still print out all members
(with value 0) in the dump function.
This patch introduces early exits in the Prologue::dump function so that
we print only the fields that were parsed successfully. In case of an
unsupported version, we skip printing all subsequent prologue fields --
because we don't even know if this version has those fields. In case of a
reserved unit length, we don't print anything -- if the very first field
of the prologue is invalid, it's hard to say if we even have a prologue
to begin with.
Note that the user will still be able to see the invalid/reserved
initial length value in the error message. I've modified (reordered)
debug_line_invalid.test to show that the error message comes straight
after the debug_line offset. I've also added some flush() calls to the
dumping code to ensure this is the case in all situations (without that,
the warnings could get out of sync if the output was not a terminal -- I
guess this is why std::iostreams have the tie() function).
Reviewers: jhenderson, ikudrin, dblaikie
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75043
Summary:
This patch if motivated by D74560, specifically the subthread about what
to print upon encountering reserved initial length values.
If the debug_line prologue has an unsupported version, we skip parsing
the rest of the data. If we encounter an reserved initial length field,
we don't even parse the version. However, we still print out all members
(with value 0) in the dump function.
This patch introduces early exits in the Prologue::dump function so that
we print only the fields that were parsed successfully. In case of an
unsupported version, we skip printing all subsequent prologue fields --
because we don't even know if this version has those fields. In case of a
reserved unit length, we don't print anything -- if the very first field
of the prologue is invalid, it's hard to say if we even have a prologue
to begin with.
Note that the user will still be able to see the invalid/reserved
initial length value in the error message. I've modified (reordered)
debug_line_invalid.test to show that the error message comes straight
after the debug_line offset. I've also added some flush() calls to the
dumping code to ensure this is the case in all situations (without that,
the warnings could get out of sync if the output was not a terminal -- I
guess this is why std::iostreams have the tie() function).
Reviewers: jhenderson, ikudrin, dblaikie
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75043
Prior to this patch, if a DW_LNE_set_address opcode was parsed with an
address size (i.e. with a length after the opcode) of anything other 1,
2, 4, or 8, an llvm_unreachable would be hit, as the data extractor does
not support other values. This patch introduces a new error check that
verifies the address size is one of the supported sizes, in common with
other places within the DWARF parsing.
This patch also fixes calculation of a generated line table's size in
unit tests. One of the tests in this patch highlighted a bug introduced
in 1271cde474, when non-byte operands were used as arguments for
extended or standard opcodes.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D73962
The DWARFv2-4 specification for the line table header states that the
include directories and file name tables both end with a single null
byte. Prior to this change, the parser did not detect if this byte was
missing, because it also stopped reading the tables once it reached the
prologue end, as claimed by the header_length field. This change adds a
check that the terminator has been seen at the end of each table.
Reviewed by: dblaikie, MaskRay
Differential Revision: https://reviews.llvm.org/D74413
The number of standard opcodes is defined to be opcode_base - 1, so a
value of 0 for the opcode_base caused a crash as an attempt was made to
reserve many entries in a vector. This change fixes the crash, by
issuing a warning and skipping reading of standard opcode lengths in the
event of an opcode_base of 0.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D74309
Also remove some test duplication and add a test case that shows the
maximum version is rejected (this also shows that the value in the error
message is actually in decimal, and not just missing an 0x prefix).
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D74403
Summary:
Dwarf stores source-file names the three parts:
<compilation_directory><include_directory><filename>
Prior to this change, the code only allowed retrieving either all
three as the absolute path, or just the filename. But many
compile-command lines--especially those in hermetic build systems
don't specify an absolute path, nor just the filename, but rather the
path relative to the compilation directory. This features allows
retrieving them in that style.
Add tests for path printing styles.
Modify createBasicPrologue to handle include directories.
Subscribers: aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73383
Summary:
That patch is extracted from https://reviews.llvm.org/D74308.
Currently there are two patterns to name error handling functions:
using "Callback" and "Handler". This patch uses "Handler" for all
usage places.
Reviewers: jhenderson, dblaikie, probinson, aprantl
Reviewed By: jhenderson, dblaikie
Subscribers: hiraditya, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D74354
If a debug line section with version of greater than 5 is encountered,
prior to this change the parser would accept it and treat it as version
5. This might work to some extent, but then it might not at all, as it
really depends on the format of the unspecified future version, which
will be different (otherwise there would be no point in changing the
version number). Any information we could provide has a good chance of
being invalid, so we should just refuse to parse such tables.
Reviewed by: dblaikie, MaskRay
Differential Revision: https://reviews.llvm.org/D74204
The function a) returned 32-bits when in DWARF64, the PrologueLength
field is 64-bits in size, and b) didn't work for DWARF version 5.
Also deleted some related dead code. With this deletion, getLength is
itself dead, but another change is about to make use of it.
Reviewed by: probinson
Differential Revision: https://reviews.llvm.org/D73626
Summary:
Add test case for the same. This test case will also serve as a
starting point for later symbolizer tests.
Reviewers: dblaikie, jdoerfert
Subscribers: hiraditya, llvm-commits, jhenderson
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73583
Many of the debug line prologue errors are not inherently fatal. In most
cases, we can make reasonable assumptions and carry on. This patch does
exactly that. In the case of length problems, the approach of "assume
stated length is correct" is taken which means the offset might need
adjusting.
This is a relanding of b94191fe, fixing an LLD test and the LLDB build.
Reviewed by: dblaikie, labath
Differential Revision: https://reviews.llvm.org/D72158
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Many of the debug line prologue errors are not inherently fatal. In most
cases, we can make reasonable assumptions and carry on. This patch does
exactly that. In the case of length problems, the approach of "the
claimed length is correct" is taken to be consistent with other
instances such as the SectionParser, which ignores the read length.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D72158
It is possible to try to keep parsing a debug line program even when the
length of an extended opcode does not match what is expected for that
opcode. This patch changes what was previously a fatal error to be
non-fatal. The parser now continues by assuming the the claimed length
is correct, even if it means moving the offset backwards.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D72155
Summary:
This patch implements `formatv()` formatting for `dwarf::LineNumberOps`
and makes use of it for the `llvm-dwarfdump --debug-line` dump.
Previously, unknown line number standard opcodes would lead to undefined
behaviour. The code would attempt to format the data pointer of an empty
`StringRef` (a null pointer) using `%s`. According to the description
for `format()`, use of that interface carries the "risk of `printf`".
Passing a null pointer in place of an array to a C library function
results in undefined behaviour.
Reviewers: jhenderson, daltenty, stevewan
Reviewed By: jhenderson
Subscribers: aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72369
Reasonable assumptions can be made when a parsed address length does not
match the expected length, so there's no need for this to be fatal.
Reviewed by: ikudrin
Differential Revision: https://reviews.llvm.org/D72154
Unlike most of our errors in the debug line parser, the "no end of
sequence" message was missing any reference to which line table it
refererred to. This change adds the offset to this message.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D72443
If the claimed unit length of a debug line program is such that the line
table would finish past the end of the .debug_line section, an infinite
loop occurs because the data extractor will continue to "read" zeroes
without changing the offset. This previously didn't hit an error because
the line table program handles a series of zeroes as a bad extended
opcode.
This patch fixes the inifinite loop and adds a warning if the program
doesn't fit in the available data.
Reviewed by: JDevlieghere
Differential Revision: https://reviews.llvm.org/D72279
When getting the file name form the line table prologue we assume that a
valid string form value can always be extracted as a string. If you look
at the implementation of DWARFormValue this is not necessarily true. I
hit this assertion from LLDB when I create a "dummy" DWARFContext that
was missing the string section.
The V5 directory and filename tables had checks in to make sure we
hadn't read past the end of the line table prologue. Since previous
changes to the data extractor class ensure we never read past the end,
these checks are now redundant, so this patch removes them.
There is still a check to show that the whole prologue remains within
the prologue length.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D71768
This patch fixes an inconsistency where we were using std::function in
some places and function_ref in others to pass around the error handling
callback.
Reviewed by: MaskRay
Differential Revision: https://reviews.llvm.org/D71762
The debug line verbose printing was printing the wrong values for rows
added via DW_LNE_end_sequence, because the row was being printed AFTER
its state had been reset following it being appended to the line table.
This patch fixes this issue by printing the row before appending it.
Reviewers: dblaikie, MaskRay
Differential Revision: https://reviews.llvm.org/D71664
Commit 84a9756 added an extra blank line at the end of any line table.
However, a blank line is also printed after the line table header, which
meant that two blank lines in a row were being printed after a header,
if there were no rows. This patch defers the post-header blank line
printing until it has been determined that there are rows to print.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D71540
This helps delineate it in the output from later tables or other output.
Reviewed by: JDevlieghere
Differential Revision: https://reviews.llvm.org/D71344
The Isa register is a uint8_t, but at least on Windows this is
internally an unsigned char, which meant that prior to this patch it got
formatted as an ASCII character, rather than a decimal number. This
patch fixes this by casting it to a uint64_t before printing. I did it
this way instead of using a uint8_t formatter because a) it is simpler,
and b) it allows us to change the internal type of Isa in the future
without this code breaking.
I also took the opportunity to test the printing of the other standard
opcodes.
Reviewed by: probinson
Differential Revision: https://reviews.llvm.org/D71274
In r368879 I made an attempt to guess the path style from the files in
the line table. After some consideration I now think this is a poor
idea. This patch undoes that behavior and instead adds an optional
argument to specify the path style. This allows us to make that decision
elsewhere where we have more information. In case of LLDB based on the
Unit.
llvm-svn: 369072
After switching over LLDB's line table parser to libDebugInfo, we
noticed two regressions on the Windows bot. The problem is that when
obtaining a file from the line table prologue, we append paths without
specifying a path style. This leads to incorrect results on Windows for
debug info containing Posix paths:
0x0000000000201000: /tmp\b.c, is_start_of_statement = TRUE
This patch is an attempt to fix that by guessing the path style whenever
possible.
Differential revision: https://reviews.llvm.org/D66227
llvm-svn: 368879
This updates all libraries and tools in LLVM Core to use 64-bit offsets
which directly or indirectly come to DataExtractor.
Differential Revision: https://reviews.llvm.org/D65638
llvm-svn: 368014
This patch exnteds the error handling in the debug line parser to get
rid of the existing MD5 assertion. I want to reuse the debug line parser
from LLVM in LLDB where we cannot crash on invalid input.
Differential revision: https://reviews.llvm.org/D64544
llvm-svn: 366762
When code relaxation is enabled many RISC-V fixups are not resolved but
instead relocations are emitted. This happens even for DWARF debug
sections. Therefore, to properly support the parsing of DWARF debug info
we need to be able to resolve RISC-V relocations. This patch adds:
* Support for RISC-V relocations in RelocationResolver
* DWARF support for two relocations per object file offset
* DWARF changes to support relocations in more DIE fields
The two relocations per offset change is needed because some RISC-V
relocations (used for label differences) come in pairs.
Relocations can also be emitted for DWARF fields where relocations were
not yet evaluated. Adding relocation support for some of these fields is
essencial. On the other hand, LLVM currently emits RISC-V relocations
for fixups that could be safely evaluated, since they can never be
affected by code relaxations. This patch also adds relocation support
for the fields affected by those extraneous relocations (the DWARF unit
entry Length, and the DWARF debug line entry TotalLength and
PrologueLength), for testing purposes.
Differential Revision: https://reviews.llvm.org/D62062
Patch by Luís Marques.
llvm-svn: 366402
The DWARF3 documentation had inconsistency concerning the reserved range
for unit length values. The issue was fixed in DWARF4.
Differential Revision: https://reviews.llvm.org/D64622
llvm-svn: 366190
Pavel Labath