Summary:
Motivation: In previous dwarf versions, file name indexes started from 1, and
the primary source file was not explicit. Dwarf 5 standard (6.2.4) prescribes
the primary source file to be explicitly given an entry with an index number 0.
The current implementation honors the specification by just duplicating the
main source file, once with index number 0, and later maybe with another
index number. While this is compliant with the letter of the standard, the
duplication causes problems for consumers of this information such as lldb.
(Some files are duplicated, where only some of them have a line table although
all refer to the same file)
With this change, dwarf 5 debug line section files always start from 0, and
the zeroth entry is not duplicated whenever possible. This requires different
handling of dwarf 4 and dwarf 5 during generation (e.g. when a function returns
an index zero for a file name, it signals an error in dwarf 4, but not in dwarf 5)
However, I think the minor complication is worth it, because it enables all
consumers (lldb, gdb, dwarfdump, objdump, and so on) to treat all files in the
file name list homogenously.
Reviewers: dblaikie, probinson, aprantl, espindola
Reviewed By: probinson
Subscribers: emaste, jvesely, nhaehnle, aprantl, javed.absar, arichardson, hiraditya, MaskRay, rupprecht, jdoerfert, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D59515
llvm-svn: 356941
[Symbolizer] Add getModuleSectionIndexForAddress() helper routine
The https://reviews.llvm.org/D58194 patch changed symbolizer interface.
Particularily it requires not only Address but SectionIndex also.
Note object::SectionedAddress parameter:
Expected<DILineInfo> symbolizeCode(const std::string &ModuleName,
object::SectionedAddress ModuleOffset,
StringRef DWPName = "");
There are callers of symbolizer which do not know particular section index.
That patch creates getModuleSectionIndexForAddress() routine which
will detect section index for the specified address. Thus if caller
set ModuleOffset.SectionIndex into object::SectionedAddress::UndefSection
state then symbolizer would detect section index using
getModuleSectionIndexForAddress routine.
Differential Revision: https://reviews.llvm.org/D58848
llvm-svn: 356829
Summary:
getRelocatedValue may compute incorrect value for SHT_RELA-typed relocation entries.
// DWARFDataExtractor.cpp
uint64_t DWARFDataExtractor::getRelocatedValue(uint32_t Size, uint32_t *Off,
...
// This formula is correct for REL, but may be incorrect for RELA if the value
// stored in the location (getUnsigned(Off, Size)) is not zero.
return getUnsigned(Off, Size) + Rel->Value;
In this patch, we
* refactor these visit* functions to include a new parameter `uint64_t A`.
Since these visit* functions are no longer used as visitors, rename them to resolve*.
+ REL: A is used as the addend. A is the value stored in the location where the
relocation applies: getUnsigned(Off, Size)
+ RELA: The addend encoded in RelocationRef is used, e.g. getELFAddend(R)
* and add another set of supports* functions to check if a given relocation type is handled.
DWARFObjInMemory uses them to fail early.
Reviewers: echristo, dblaikie
Reviewed By: echristo
Subscribers: mgorny, aprantl, aheejin, fedor.sergeev, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57939
llvm-svn: 356729
Summary:
This considers module symbol streams and the global symbol stream to be
roots. Most types that this considers "unreferenced" are referenced by
LF_UDT_MOD_SRC_LINE id records, which VC seems to always include.
Essentially, they are types that the user can only find in the debugger
if they call them by name, they cannot be found by traversing a symbol.
In practice, around 80% of type information in a PDB is referenced by a
symbol. That seems like a reasonable number.
I don't really plan to do anything with this tool. It mostly just exists
for informational purposes, and to confirm that we probably don't need
to implement type reference tracking in LLD. We can continue to merge
all types as we do today without wasting space.
Reviewers: zturner, aganea
Subscribers: mgorny, hiraditya, arphaman, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59620
llvm-svn: 356692
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.
The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.
For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.
This is a recommit of r356442 with trivial fixes for the failing tests.
Differential Revision: https://reviews.llvm.org/D56587
llvm-svn: 356451
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.
The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.
For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.
Differential Revision: https://reviews.llvm.org/D56587
llvm-svn: 356442
Before, empty debug streams were written as 8 bytes (4 bytes signature + 4 bytes for the GlobalRefs count).
With this patch, unused empty streams aren't emitted anymore. Modules now encode 65535 as an 'unused stream' value, by convention.
Also fix the * Linker * contrib section which wasn't correctly emitted previously.
Differential Revision: https://reviews.llvm.org/D59502
llvm-svn: 356395
Summary:
This is similar to how addr2line handles consecutive entries with the
same address - pick the last one.
Reviewers: dblaikie, friss, JDevlieghere
Reviewed By: dblaikie
Subscribers: eugenis, vitalybuka, echristo, JDevlieghere, probinson, aprantl, hiraditya, rupprecht, jdoerfert, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D58952
llvm-svn: 356265
Summary:
This is similar to how addr2line handles consecutive entries with the
same address - pick the last one.
Reviewers: dblaikie, friss, JDevlieghere
Reviewed By: dblaikie
Subscribers: ormris, echristo, JDevlieghere, probinson, aprantl, hiraditya, rupprecht, jdoerfert, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D58952
llvm-svn: 355972
Summary:
Swift now generates PDBs for debugging on Windows. llvm and lldb
need a language enumerator value too properly handle the output
emitted by swiftc.
Subscribers: jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59231
llvm-svn: 355882
Change the format type of *Personality and *LSDAAddress to PRIx64 since
they are of type uint64_t.
The problem was detected on mips builds, where it was printing junk values
and causing test failure.
Patch by Milos Stojanovic.
Differential Revision: https://reviews.llvm.org/D58451
llvm-svn: 355607
When dumping ToT clan's debug info with dwarfdump, we were seeing an
error saying that that the location list overflows the debug_loc
section. After reducing the testcase we figured out that we were
interpreting the DW_FORM_data4 as a section offset.
In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section
offset. Until now we didn't check check for the DWARF version, because
some producers (read old versions of clang) were still emitting this.
The relevant code/comment was added in 2013, and I believe it's now
reasonable to start checking the version.
The FormValue class is a little bit of a mess because it cashes the
DWARF unit and context when it extracted the value itself. Several
methods of the class rely on it being present, or return an Optional for
the code path that needs it. At the same time the FormValue class also
used in places where there's no DWARF unit.
For this patch I went with the least invasive change: checking the
version from the CU when it's available. If it's not (because the form
value was created from a value directly) we default to the old behavior.
Differential revision: https://reviews.llvm.org/D58698
llvm-svn: 355456
Add support for cloning DWARF expressions that contain base type DIE
references in dsymutil.
<rdar://problem/48167812>
Differential Revision: https://reviews.llvm.org/D58534
llvm-svn: 355148
That patch is the fix for https://bugs.llvm.org/show_bug.cgi?id=40703
"wrong line number info for obj file compiled with -ffunction-sections"
bug. The problem happened with only .o files. If object file contains
several .text sections then line number information showed incorrectly.
The reason for this is that DwarfLineTable could not detect section which
corresponds to specified address(because address is the local to the
section). And as the result it could not select proper sequence in the
line table. The fix is to pass SectionIndex with the address. So that it
would be possible to differentiate addresses from various sections. With
this fix llvm-objdump shows correct line numbers for disassembled code.
Differential review: https://reviews.llvm.org/D58194
llvm-svn: 354972
DWARFFormValues can be created from a data extractor or by passing its
value directly. Until now this was done by member functions that
modified an existing object's internal state. This patch replaces a
subset of these methods with static method that return a new
DWARFFormValue.
llvm-svn: 354941
Adds llvm-dwarfdump support for pretty printing Dwarf5 expressions ops
that reference a base type (right now only DW_OP_convert is added).
Includes verification to verify that the ops operand is actually a
DW_TAG_base_type DIE.
Differential Revision: https://reviews.llvm.org/D58442
llvm-svn: 354552
Summary:
llvm-symbolizer would originally report symbols that belonged to an invalid object file section.
Specifically the case where: `*Symbol.getSection() == ObjFile.section_end()`
This patch prevents the Symbolizer from collecting symbols that belong to invalid sections.
The test (from PR40591) introduces a case where two symbols have address 0,
one symbol is defined, 'foo', and the other is not defined, 'bar'. This patch will cause
the Symbolizer to keep 'foo' and ignore 'bar'.
As a side note, the logic for adding symbols to the Symbolizer's store
(`SymbolizableObjectFile::addSymbol`) replaces symbols with the
same <address, size> pair. At some point that logic should be revisited as in the
aforementioned case, 'bar' was overwriting 'foo' in the Symbolizer's store,
and 'foo' was forgotten.
This fixes PR40591
Reviewers: jhenderson, rupprecht
Reviewed By: rupprecht
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58146
llvm-svn: 354083
Summary:
rL189250 added a realpath call, and rL352916 because realpath breaks assumptions with some build systems. However, the /usr/lib/debug case has been clarified, falling back to /usr/lib/debug is currently broken if the obj passed in is a relative path. Adding a call to use absolute paths when falling back to /usr/lib/debug fixes that while still not making any realpath assumptions.
This also adds a --fallback-debug-path command line flag for testing (since we probably can't write to /usr/lib/debug from buildbot environments), but was also verified manually:
```
$ rm -f path/to/dwarfdump-test.elf-x86-64
$ strace llvm-symbolizer --obj=relative/path/to/dwarfdump-test.elf-x86-64.debuglink 0x40113f |& grep dwarfdump
```
Lookups went to relative/path/to/dwarfdump-test.elf-x86-64, relative/path/to/.debug/dwarfdump-test.elf-x86-64, and then finally /usr/lib/debug/absolute/path/to/dwarfdump-test.elf-x86-64.
Reviewers: dblaikie, samsonov
Reviewed By: dblaikie
Subscribers: krytarowski, aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57916
llvm-svn: 353730
When type streams with forward references were merged using GHashes, cycles
were introduced in the debug info. This was caused by
GlobalTypeTableBuilder::insertRecordAs() not inserting the record on the second
pass, thus yielding an empty ArrayRef at that record slot. Later on, upon PDB
emission, TpiStreamBuilder::commit() would skip that empty record, thus
offseting all indices that came after in the stream.
This solution comes in two steps:
1. Fix the hash calculation, by doing a multiple-step resolution, iff there are
forward references in the input stream.
2. Fix merge by resolving with multiple passes, therefore moving records with
forward references at the end of the stream.
This patch also adds support for llvm-readoj --codeview-ghash.
Finally, fix dumpCodeViewMergedTypes() which previously could reference deleted
memory.
Fixes PR40221
Differential Revision: https://reviews.llvm.org/D57790
llvm-svn: 353412
The wrong variable was being used when printing the address increment in
verbose output of .debug_line. This patch fixes this.
Reviewed by: JDevlieghere
Differential Revision: https://reviews.llvm.org/D57693
llvm-svn: 353288
Summary:
Using realpath makes assumptions about build systems that do not always hold true. The debug binary referred to from the .gnu_debuglink should exist in the same directory (or in a .debug directory, etc.), but the files may only exist as symlinks to a differently named files elsewhere, and using realpath causes that lookup to fail.
This was added in r189250, and this is basically a revert + regression test case.
Reviewers: dblaikie, samsonov, jhenderson
Reviewed By: dblaikie
Subscribers: llvm-commits, hiraditya
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57609
llvm-svn: 352916
Summary:
This patch fixes access to fpo streams in native pdb from DbiStream and makes
code consistent with DbiStreamBuilder.
Patch By: leonid.mashinskiy
Reviewers: zturner, aleksandr.urakov
Reviewed By: zturner
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56725
llvm-svn: 352615
PDBs contain several serialized hash tables. In the microsoft-pdb
repo published to support LLVM implementing PDB support, the
provided initializes the bucket count for the TPI and IPI streams
to the maximum size. This occurs in tpi.cpp L33 and tpi.cpp L398.
In the LLVM code for generating PDBs, these streams are created with
minimum number of buckets. This difference makes LLVM generated
PDBs slower for when used for debugging.
Patch by C.J. Hebert
Differential Revision: https://reviews.llvm.org/D56942
llvm-svn: 352117
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
This is difficult/not possible to test in LLVM, but is visible as a
crash in LLD when parsing DWARF to generate gdb-index.
This function is called by llvm-dwarfdump when parsing high_pc for
non-verbose output (to print the actual high_pc rather than the low_pc
relative value), but in that case llvm-dwarfdump doesn't print section
names (if it did, it would hit this problem).
We could add some other features to llvm-dwarfdump to expose this, but
nothing really springs to my mind. I will add a test to lld, though.
llvm-svn: 350010
Currently the section name (& possibly number) is only printed on
addresses in ranges - but no reason it couldn't also be displayed on
other addresses (like low/high PC).
Refactor in that direction by pulling out the section lookup and name
ambiguity dumping logic into a reusable helper.
llvm-svn: 349995
Propagate the llvm::Error a little further up. This is NFC for
llvm-dwarfdump in this change, but allows ld.lld to emit more precise
error messages about which object and archive the erroneous DWARF is in.
llvm-svn: 349978
Originally committed in r349333, reverted in r349353.
GCC emitted these unconditionally on/before 4.4/March 2012
Clang emitted these unconditionally on/before 3.5/March 2014
This improves performance when parsing CUs (especially those using split
DWARF) that contain no code ranges (such as the mini CUs that may be
created by ThinLTO importing - though generally they should be/are
avoided, especially for Split DWARF because it produces a lot of very
small CUs, which don't scale well in a bunch of other ways too
(including size)).
The revert was due to a (Google internal) test that had some checked in old
object files missing DW_AT_ranges. That's since been fixed.
llvm-svn: 349968
- When signing return addresses with -msign-return-address=<scope>{+<key>},
either the A key instructions or the B key instructions can be used. To
correctly authenticate the return address, the unwinder/debugger must know
which key was used to sign the return address.
- When and exception is thrown or a break point reached, it may be necessary to
unwind the stack. To accomplish this, the unwinder/debugger must be able to
first authenticate an the return address if it has been signed.
- To enable this, the augmentation string of CIEs has been extended to allow
inclusion of a 'B' character. Functions that are signed using the B key
variant of the instructions should have and FDE whose associated CIE has a 'B'
in the augmentation string.
- One must also be able to preserve these semantics when first stepping from a
high level language into assembly and then, as a second step, into an object
file. To achieve this, I have introduced a new assembly directive
'.cfi_b_key_frame ', that tells the assembler the current frame uses return
address signing with the B key.
- This ensures that the FDE is associated with a CIE that has 'B' in the
augmentation string.
Differential Revision: https://reviews.llvm.org/D51798
llvm-svn: 349895
This is to address post-commit feedback from Paul Robinson on r348954.
The original commit misinterprets count and upper bound as the same thing (I thought I saw GCC producing an upper bound the same as Clang's count, but GCC correctly produces an upper bound that's one less than the count (in C, that is, where arrays are zero indexed)).
I want to preserve the C-like output for the common case, so in the absence of a lower bound the count (or one greater than the upper bound) is rendered between []. In the trickier cases, where a lower bound is specified, a half-open range is used (eg: lower bound 1, count 2 would be "[1, 3)" and an unknown parts use a '?' (eg: "[1, ?)" or "[?, 7)" or "[?, ? + 3)").
Reviewers: aprantl, probinson, JDevlieghere
Differential Revision: https://reviews.llvm.org/D55721
llvm-svn: 349670
- Reapply changes intially introduced in r343089
- The archtecture info is no longer loaded whenever a DWARFContext is created
- The runtimes libraries (santiziers) make use of the dwarf context classes but
do not intialise the target info
- The architecture of the object can be obtained without loading the target info
- Adding a method to the dwarf context to get this information and multiplex the
string printing later on
Differential Revision: https://reviews.llvm.org/D55774
llvm-svn: 349472
GCC emitted these unconditionally on/before 4.4/March 2012
Clang emitted these unconditionally on/before 3.5/March 2014
This improves performance when parsing CUs (especially those using split
DWARF) that contain no code ranges (such as the mini CUs that may be
created by ThinLTO importing - though generally they should be/are
avoided, especially for Split DWARF because it produces a lot of very
small CUs, which don't scale well in a bunch of other ways too
(including size)).
llvm-svn: 349333
Doesn't handle varargs and other fun things, but it's a start. (also
doesn't print these strictly as valid C++ when it's a pointer to
function, it'll print as "void(int)*" instead of "void (*)(int)")
llvm-svn: 348965
