When concatenating directory with filename in getFilenameByIndex, we
might end up with a path that contains extra dots. For example, if the
input is /path and ./example, we would return /path/./example. Run
sys::path::remove_dots on the output to eliminate unnecessary dots.
Differential Revision: https://reviews.llvm.org/D87657
LTO builds have been creating invalid DWARF and one of the errors was a file index that was out of bounds. "llvm-dwarfdump --verify" will check all file indexes for line tables already, but there are no checks for the validity of file indexes in attributes.
The verification will verify if there is a DW_AT_decl_file/DW_AT_call_file that:
- there is a line table for the compile unit
- the file index is valid
- the encoding is appropriate
Tests are added that test all of the above conditions.
Differential Revision: https://reviews.llvm.org/D84817
Previously, the debug line parser would keep attempting to read data
even if it had run out of data to read. This meant errors in parsing
would often end up being reported as something else, such as an unknown
version or malformed directory/filename table. This patch fixes the
issues by using the Cursor API to capture errors.
Reviewed by: labath
Differential Revision: https://reviews.llvm.org/D83043
Previously, if there was an error whilst parsing the operands of an
extended opcode, the operands would be treated as zero and printed. This
could potentially be slightly confusing. This patch changes the
behaviour to print the raw bytes instead.
Reviewed by: ikudrin
Differential Revision: https://reviews.llvm.org/D81570
This is a natural extension of the previous changes to use the Cursor
class independently in the standard and extended opcode paths, and in
turn allows delaying error handling until the entire line has been
printed in verbose mode, removing interleaved output in some cases.
Reviewed by: MaskRay, JDevlieghere
Differential Revision: https://reviews.llvm.org/D81562
Standard opcodes usually have ULEB128 arguments, so it is generally not
possible to recover from such errors. This patch causes the parser to
stop parsing the table in such situations.
Also don't emit the operands or add data to the table if there is an
error reading these opcodes.
Reviewed by: JDevlieghere
Differential Revision: https://reviews.llvm.org/D81470
Summary:
This makes the code easier to reason about, as it will behave the same
way regardless of whether there is any more data coming after the
presumed end of the prologue.
Reviewers: jhenderson, dblaikie, probinson, ikudrin
Subscribers: hiraditya, MaskRay, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D77557
The verbose printing of unrecognised standard opcodes was broken in
multiple ways (additional blank lines, a closing parenthesis without
opening parenthesis and so on). This patch fixes it, and makes the
output more consistent with other opcodes.
The new line printing for debug line verbose output was inconsistent.
For new rows in the matrix, a blank line followed, whilst the
DW_LNS_copy opcode actually resulted in two blank lines. There was also
potential inconsistency in the blank lines at the end of the table. This
patch mostly resolves these issues - no blank lines appear in the output
except for a single line after the prologue and at table end to separate
it from any subsquent table, plus some instances after error messages.
Also add a unit test for verbose output to test the fine details of new
line placement and other aspects of verbose output.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D81102
Verbose and non-verbose parsing of .debug_line produced their output at
different points in the program. The most obvious impact of this was
that error messages were produced at different times, but it also
potentially reduced what clients could do by customising the stream or
warning/error handlers.
This change makes the two variants consistent by printing non-verbose
output inline, the same as verbose output.
Testing of the error messages has been modified to check the messages
always appear in the same location to illustrate the behaviour.
Reviewed by: JDevlieghere, dblaikie, MaskRay, labath
Differential Revision: https://reviews.llvm.org/D80989
Previously, if an extended opcode was truncated, it would manifest as an
"unexpected line op length error" which wasn't quite accurate. This
change checks for errors any time data is read whilst parsing an
extended opcode, and reports any errors detected.
Reviewed by: MaskRay, labath, aprantl
Differential Revision: https://reviews.llvm.org/D80797
Like non-verbose output, so that it is easy to recognize the `Line,Column,File,ISA,Discriminator` column values.
Reviewed By: JDevlieghere, jhenderson
Differential Revision: https://reviews.llvm.org/D80874
Update for upstream comments. Improve test by writing all the debug
info by hand.
Reviewers: dblaikie, jhenderson
Subscribers: hiraditya, MaskRay, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D80168
This will ensure that nothing can ever start parsing data from a future
sequence and part-read data will be returned as 0 instead.
Reviewed by: aprantl, labath
Differential Revision: https://reviews.llvm.org/D80796
The patch changes dumping of unit_length and header_length fields in
headers in .debug_line sections so that they are printed as 16-digit hex
values if the contribution is in the DWARF64 format.
Differential Revision: https://reviews.llvm.org/D79997
Summary:
Without this we could silently accept an invalid prologue because the
default DataExtractor behavior is to return an empty string when
reaching the end of file. And empty string is also used to terminate
these lists.
This makes the parsing code slightly more complicated, but this
complexity will go away once the parser starts working with truncating
data extractors. The reason I am doing it this way is because without
this, the truncation would regress the quality of error messages (right
now, we produce bad error messages only near EOF, but truncation would
make everything behave as if it was near EOF).
Reviewers: dblaikie, probinson, jhenderson
Subscribers: hiraditya, MaskRay, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D77555
Summary:
Without that we could be silently reading zeroes, as that's the default
DataExtractor behavior. The entire parse would still most likely fail,
but it would do that with a seemingly unrelated/nonsensical error
message.
Reviewers: dblaikie, probinson, jhenderson
Subscribers: hiraditya, MaskRay, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D77554
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.
David Blaikie