This patch adds the ability to evaluate the state machine for CIE and FDE unwind objects and produce a UnwindTable with all UnwindRow objects needed to unwind registers. It will also dump the UnwindTable for each CIE and FDE when dumping DWARF .debug_frame or .eh_frame sections in llvm-dwarfdump or llvm-objdump. This allows users to see what the unwind rows actually look like for a given CIE or FDE instead of just seeing a list of opcodes.
This patch adds new classes: UnwindLocation, RegisterLocations, UnwindRow, and UnwindTable.
UnwindLocation is a class that describes how to unwind a register or Call Frame Address (CFA).
RegisterLocations is a class that tracks registers and their UnwindLocations. It gets populated when parsing the DWARF call frame instruction opcodes for a unwind row. The registers are mapped from their register numbers to the UnwindLocation in a map.
UnwindRow contains the result of evaluating a row of DWARF call frame instructions for the CIE, or a row from a FDE. The CIE can produce a set of initial instructions that each FDE that points to that CIE will use as the seed for the state machine when parsing FDE opcodes. A UnwindRow for a CIE will not have a valid address, whille a UnwindRow for a FDE will have a valid address.
The UnwindTable is a class that contains a sorted (by address) vector of UnwindRow objects and is the result of parsing all opcodes in a CIE, or FDE. Parsing a CIE should produce a UnwindTable with a single row. Parsing a FDE will produce a UnwindTable with one or more UnwindRow objects where all UnwindRow objects have valid addresses. The rows in the UnwindTable will be sorted from lowest Address to highest after parsing the state machine, or an error will be returned if the table isn't sorted. To parse a UnwindTable clients can use the following methods:
static Expected<UnwindTable> UnwindTable::create(const CIE *Cie);
static Expected<UnwindTable> UnwindTable::create(const FDE *Fde);
A valid table will be returned if the DWARF call frame instruction opcodes have no encoding errors. There are a few things that can go wrong during the evaluation of the state machine and these create functions will catch and return them.
Differential Revision: https://reviews.llvm.org/D89845
... because using unsigned constants for comparing against signed values
is liable to mutate the signed value via conversion to an unsigned type
due to the usual arithmetic conversions.
Most clients only need CVType and CVSymbol, not structs for every type
and symbol. Move CVSymbol and CVType to CVRecord.h to accomplish this.
Update some of the common headers that need CVSymbol and CVType to use
the new location.
In the case of LTO, several DWARF units can be emitted in one section.
For an extremely large application, they may exceed the limit of 4GiB
for 32-bit offsets. As it is now possible to emit 64-bit debugging info,
the patch enables storing the larger offsets.
Differential Revision: https://reviews.llvm.org/D87026
The Length, AbbrOffset and Values fields of the debug_info section are
optional. This patch helps remove them and simplify test cases.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D86857
This patch helps make the debug_abbrev_offset field optional. We don't
need to calculate the value of this field in the future.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D86614
This patch makes the unit_length and header_length fields of line tables
optional. yaml2obj is able to infer them for us.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D86590
This patch makes the 'Attributes' field optional. We don't need to
explicitly specify the 'Attributes' field in the future.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D86537
The original commit (7ff0ace96db9164dcde232c36cab6519ea4fce8) was causing
build failure and was reverted in 6d242a73264ef1e3e128547f00e0fe2d20d3ada0
==================== Original Commit Message ====================
This patch adds support for referencing different abbrev tables. We use
'ID' to distinguish abbrev tables and use 'AbbrevTableID' to explicitly
assign an abbrev table to compilation units.
The syntax is:
```
debug_abbrev:
- ID: 0
Table:
...
- ID: 1
Table:
...
debug_info:
- ...
AbbrevTableID: 1 ## Reference the second abbrev table.
- ...
AbbrevTableID: 0 ## Reference the first abbrev table.
```
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D83116
This patch adds support for referencing different abbrev tables. We use
'ID' to distinguish abbrev tables and use 'AbbrevTableID' to explicitly
assign an abbrev table to compilation units.
The syntax is:
```
debug_abbrev:
- ID: 0
Table:
...
- ID: 1
Table:
...
debug_info:
- ...
AbbrevTableID: 1 ## Reference the second abbrev table.
- ...
AbbrevTableID: 0 ## Reference the first abbrev table.
```
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D83116
This patch adds support for emitting multiple abbrev tables. Currently,
compilation units will always reference the first abbrev table.
Reviewed By: jhenderson, labath
Differential Revision: https://reviews.llvm.org/D86194
Although the DWARF specification states that .debug_aranges entries
can't have length zero, these can occur in the wild. There's no
particular reason to enforce this part of the spec, since functionally
they have no impact. The patch removes the error and introduces a new
warning for premature terminator entries which does not stop parsing.
This is a relanding of cb3a598c87db, adding the missing obj2yaml part
that was needed.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46805. See also
https://reviews.llvm.org/D71932 which originally introduced the error.
Reviewed by: ikudrin, dblaikie, Higuoxing
Differential Revision: https://reviews.llvm.org/D85313
Although the DWARF specification states that .debug_aranges entries
can't have length zero, these can occur in the wild. There's no
particular reason to enforce this part of the spec, since functionally
they have no impact. The patch removes the error and introduces a new
warning for premature terminator entries which does not stop parsing.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46805. See also
https://reviews.llvm.org/D71932 which originally introduced the error.
Reviewed by: ikudrin, dblaikie
Differential Revision: https://reviews.llvm.org/D85313
This removes members of the DIEUnit class which were used only in unit
tests. Note also that child classes shadowed some of these methods,
namely, getDwarfVersion() was overridden in DwartfUnit and getLength()
was overridden in DwarfCompileUnit.
Differential Revision: https://reviews.llvm.org/D85436
DWARFYAML supports generating the .debug_loclists section. We can use it
to simplify tests.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D85179
This patch refactors `emitDebugInfo()` to make the length field be
inferred from its content. Besides, the `Visitor` class is removed in
this patch. The original `Visitor` class helps us determine an
appropriate length and emit the .debug_info section. These two
processes can be merged into one process. Besides, the length field
should be inferred when it's missing rather than when it's zero.
Reviewed By: jhenderson, labath
Differential Revision: https://reviews.llvm.org/D84008
This adds unit tests to check the expected behavior of the method in
case the unit length field is truncated.
Differential Revision: https://reviews.llvm.org/D83673
Add a unit test for the compact DWARF expression printer which will be
used by the llvm-objdump --debug-vars option.
Differential revision: https://reviews.llvm.org/D75250
There are following issues with `CFIProgram::parse` code:
1) Invalid CFI opcodes were never tested. And currently a test would fail
when the `LLVM_ENABLE_ABI_BREAKING_CHECKS` is enabled. It happens because
the `DataExtractor::Cursor C` remains unchecked when the
"Invalid extended CFI opcode" error is reported:
```
.eh_frame section at offset 0x1128 address 0x0:
Program aborted due to an unhandled Error:
Error value was Success. (Note: Success values must still be checked prior to being destroyed).
```
2) It is impossible to reach the "Invalid primary CFI opcode" error with the current code.
There are 3 possible primary opcode values and all of them are handled. Hence this error
should be replaced with llvm_unreachable.
3) Errors currently reported are upper-case.
This patch refines the code in the `CFIProgram::parse` method to fix all issues mentioned
and adds unit tests for all possible invalid extended CFI opcodes.
Differential revision: https://reviews.llvm.org/D82868
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
Summary:
The byte swap fix for big endian hosts in 9782c922cb21 (for D81570)
swaps based on the host endianess, but for cross-targeting builds (i.e.
big endian host targeting little endian) the host-endianess won't
necessarily match the generated DWARF. This change updates the test
to use symmetrical constants so the results aren't endian dependent.
Reviewers: jhenderson, hubert.reinterpretcast, stevewan, ikudrin
Reviewed By: ikudrin
Subscribers: ikudrin, aprantl, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D82827
'InitialLength' is replaced with 'Format' (DWARF32 by default) and 'Length' in this patch.
Besides, test cases for DWARFv4 and DWARFv5, DWARF32 and DWARF64 is
added.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82622
Currently when the .eh_frame section is truncated so that
CFI instructions can't be read, it is possible to enter
an infinite loop.
It happens because `CFIProgram::parse` does not handle errors properly.
This patch fixes the issue.
Differential revision: https://reviews.llvm.org/D82017
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
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
Summary:
This is a result of the discussion at D78113. Previously we would be
only giving the current offset at which the error was detected. However,
this was phrased somewhat ambiguously (as it could also mean that end of
data was at that offset). The new error message includes the current
offset as well as the extent of the data being read.
I've changed a couple of file-level static functions into private member
functions in order to avoid passing a bunch of new arguments everywhere.
Reviewers: dblaikie, jhenderson
Subscribers: hiraditya, MaskRay, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78558
The patch changes dumping of DWARF form values which sizes depend on
the DWARF format so that they are printed as 16-digit hex values for
DWARF64.
Differential Revision: https://reviews.llvm.org/D79997
Summary: This implements searching for function symbols and public symbols by address.
More specifically,
-Implements NativeSession::findSymbolByAddress for function symbols and
public symbols. I think data symbols are also searched for, but isn't
implemented in this patch.
-Adds classes for NativeFunctionSymbol and NativePublicSymbol
-Adds a '-use-native-pdb-reader' option to llvm-symbolizer, for testing
purposes.
Reviewers: rnk, amccarth, labath
Subscribers: mgorny, hiraditya, MaskRay, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79269
We unconditionally compared the DW_AT_ranges offset to the length of the
.debug_ranges section. For DWARF5 we should look at the debug_rnglists
section instead.
Differential revision: https://reviews.llvm.org/D78971
