Initial (D96045) patch didn't handle split dwarf cases,
so this fixes that bug.
In addition, before applying this patch, we had a slowdown
that happened after the D96045. With this patch,
the slowdown will be fixed as well.
Differential Revision: https://reviews.llvm.org/D100951
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
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
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
Add an option to llvm-dwarfdump to calculate the bytes within
the debug sections. Dump this numbers when using --statistics
option as well.
This is an initial patch (e.g. we should support other units,
since we only support 'bytes' now).
Differential Revision: https://reviews.llvm.org/D74205
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
The DebugInfo/dwarfdump-invalid-line-table test used a pre-canned binary
generated by a fuzzer to demonstrate a bug fix. Unfortunately, the
binary is rigid and requires hand-editing if we change behaviour, such
as rejecting certain properties within it (as I plan on doing in another
change).
Rather than hand-edit the binary, I have replaced it with two tests. The
first tests the high-level code path from the debug line parser that
produces the same error as this test previously did, and the second is a
set of unit test cases that comprehensively cover the
FormValue::skipValue method, which in turn covers the area that the
original bug fix touched.
Reviewed by: MaskRay, dblaikie
Differential Revision: https://reviews.llvm.org/D74202
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
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
A subsequent patch will change how an invalid file name table is handled
to allow parsing to continue. This patch adds a test case that will
demonstrate a difference in behaviour with that change between invalid
file tables where the error is before the end of the stated prologue
length and where the error occurs after the stated length.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D72157
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
The line tables in debug_line_malformed.s had contents that varied more
than was necessary for the testing, making it harder to follow what was
important. This patch normalises them so that they all share
more-or-less the same body. Additionally, it makes the testing for what
was printed more consistent, to show that the right parts of the line
table prologue and body are/are not parsed and printed.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D71755
This patch adds and improves comments in the debug_line_invalid.test and
its associated input file so that it is easier to follow. It uses '##'
to make comments stand out from lit and FileCheck commands.
It also reflows some commands so that the lines are not so long and are
easier to read and fixes some copy/paste errors.
Reviewed by: JDevlieghere
Differential Revision: https://reviews.llvm.org/D71752
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
Add check for, and parsing of, .dwo files to Statistics.cpp; create a new getNon
SkeletonUnitDie function for DWARFUnit.h
Reviewers: dblaikie
Differential Revision: https://review.llvm.org/D61755
llvm-svn: 360380
Add statistics for abstract origins, function, variable and parameter
locations; break the 'variable' counts down into variables and
parameters. Also update call site counting to check for
DW_AT_call_{file,line} in addition to DW_TAG_call_site.
Differential revision: https://reviews.llvm.org/D58849
llvm-svn: 355243
Reviewed by: dblaikie, JDevlieghere, espindola
Differential Revision: https://reviews.llvm.org/D44560
Summary:
The .debug_line parser previously reported errors by printing to stderr and
return false. This is not particularly helpful for clients of the library code,
as it prevents them from handling the errors in a manner based on the calling
context. This change switches to using llvm::Error and callbacks to indicate
what problems were detected during parsing, and has updated clients to handle
the errors in a location-specific manner. In general, this means that they
continue to do the same thing to external users. Below, I have outlined what
the known behaviour changes are, relating to this change.
There are two levels of "errors" in the new error mechanism, to broadly
distinguish between different fail states of the parser, since not every
failure will prevent parsing of the unit, or of subsequent unit. Malformed
table errors that prevent reading the remainder of the table (reported by
returning them) and other minor issues representing problems with parsing that
do not prevent attempting to continue reading the table (reported by calling a
specified callback funciton). The only example of this currently is when the
last sequence of a unit is unterminated. However, I think it would be good to
change the handling of unrecognised opcodes to report as minor issues as well,
rather than just printing to the stream if --verbose is used (this would be a
subsequent change however).
I have substantially extended the DwarfGenerator to be able to handle
custom-crafted .debug_line sections, allowing for comprehensive unit-testing
of the parser code. For now, I am just adding unit tests to cover the basic
error reporting, and positive cases, and do not currently intend to test every
part of the parser, although the framework should be sufficient to do so at a
later point.
Known behaviour changes:
- The dump function in DWARFContext now does not attempt to read subsequent
tables when searching for a specific offset, if the unit length field of a
table before the specified offset is a reserved value.
- getOrParseLineTable now returns a useful Error if an invalid offset is
encountered, rather than simply a nullptr.
- The parse functions no longer use `WithColor::warning` directly to report
errors, allowing LLD to call its own warning function.
- The existing parse error messages have been updated to not specifically
include "warning" in their message, allowing consumers to determine what
severity the problem is.
- If the line table version field appears to have a value less than 2, an
informative error is returned, instead of just false.
- If the line table unit length field uses a reserved value, an informative
error is returned, instead of just false.
- Dumping of .debug_line.dwo sections is now implemented the same as regular
.debug_line sections.
- Verbose dumping of .debug_line[.dwo] sections now prints the prologue, if
there is a prologue error, just like non-verbose dumping.
As a helper for the generator code, I have re-added emitInt64 to the
AsmPrinter code. This previously existed, but was removed way back in r100296,
presumably because it was dead at the time.
This change also requires a change to LLD, which will be committed separately.
llvm-svn: 331971
Adding verbose dumping to the recent implementation of dumping of v5 range list entries.
We're capturing the entries as is as they come in during extraction, including their file offset,
so we can dump them in more detail.
The offset table entries which are table-relative are shown as is (as in non-verbose mode)
and with the actual file offset they map to.
Reviewers: dblaikie, aprantl, jdevlieghere, jhenderson
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43366
llvm-svn: 327059
When dsymutil generates the companion file, its strips all unnecessary
sections by omitting their body and setting the offset in their
corresponding load command to zero.
One such section is the .eh_frame section, as it contains runtime
information rather than debug information and is part of the __TEXT
segment. When reading this section, we would just read the number of
bytes specified in the load command, starting from offset 0 (i.e. the
beginning of the file).
Rather than trying to parse this obviously invalid section, dwarfdump
now skips this.
Differential revision: https://reviews.llvm.org/D38135
llvm-svn: 314208
Inputs should be placed local to the test (or possibly in a common
parent? I think we do that in some places - but the only common parent
between these two directories is 'test' which seems a bit overly broad).
llvm-svn: 313662
Adrian Prantl