Commit Graph

19 Commits

Author SHA1 Message Date
Greg Clayton 78a07bfa66 Add the ability for DWARFDie objects to get the parent DWARFDie.
In order for the llvm DWARF parser to be used in LLDB we will need to be able to get the parent of a DIE. This patch adds that functionality by changing the DWARFDebugInfoEntry class to store a depth field instead of a sibling index. Using a depth field allows us to easily calculate the sibling and the parent without increasing the size of DWARFDebugInfoEntry.

I tested llvm-dsymutil on a debug version of clang where this fully parses DWARF in over 1200 .o files to verify there was no serious regression in performance.

Added a full suite of unit tests to test this functionality.

Differential Revision: https://reviews.llvm.org/D27995

llvm-svn: 290274
2016-12-21 21:37:06 +00:00
David Blaikie 7d4a5599da Revert "dwarfdump: Support/process relocations on a CU's abbrev_off"
Reverting because this breaks lld's gdb_index support - it's probably
double counting the abbrev relocation offset.

This reverts commit r289954.

llvm-svn: 289961
2016-12-16 17:10:17 +00:00
David Blaikie e9fda9f201 dwarfdump: Support/process relocations on a CU's abbrev_off
Input can be produced by ld -r, for example (a normal LLVM workflow
never hits this - LLVM only ever produces a single abbrev table in an
object (shared by multiple CUs), so the reloc's always 0, and when it's
linked together the relocation's resolved so it doesn't need to be
handled)

llvm-svn: 289954
2016-12-16 16:31:10 +00:00
Greg Clayton 52fe1f68c8 Add the ability to get attribute values as Optional<T>
When getting attributes it is sometimes nicer to use Optional<T> some of the time instead of magic values. I tried to cut over to only using the Optional values but it made many of the call sites very messy, so it makes sense the leave in the calls that can return a default value. Otherwise code that looks like this:

uint64_t CallColumn = Die.getAttributeValueAsAddress(DW_AT_call_line, 0);

Has to be turned into:

uint64_t CallColumn = 0;
if (auto CallColumnValue = Die.getAttributeValueAsAddress(DW_AT_call_line))
    CallColumn = *CallColumnValue;

The first snippet of code looks much better. But in cases where you want an offset that may or may not be there, the following code looks better:

if (auto StmtOffset = Die.getAttributeValueAsSectionOffset(DW_AT_stmt_list)) {
  // Use StmtOffset
}

Differential Revision: https://reviews.llvm.org/D27772

llvm-svn: 289731
2016-12-14 22:38:08 +00:00
Greg Clayton c8c1032c0c Make a DWARFDIE class that can help avoid using the wrong DWARFUnit when extracting attributes
Many places pass around a DWARFDebugInfoEntryMinimal and a DWARFUnit. It is easy to get things wrong by using the wrong DWARFUnit with a DWARFDebugInfoEntryMinimal. This patch creates a DWARFDie class that contains the DWARFUnit and DWARFDebugInfoEntryMinimal objects so that they can't get out of sync. All attribute extraction has been moved out of DWARFDebugInfoEntryMinimal and into DWARFDie. DWARFDebugInfoEntryMinimal was also renamed to DWARFDebugInfoEntry.

DWARFDie objects are temporary objects that are used by clients and contain 2 pointers that you always need to have anyway. Keeping them grouped will avoid errors and simplify many of the attribute extracting APIs by not having to pass in a DWARFUnit.

Differential Revision: https://reviews.llvm.org/D27634

llvm-svn: 289565
2016-12-13 18:25:19 +00:00
Eugene Zelenko 570e39a25c [DebugInfo] Fix some Clang-tidy modernize-use-default and Include What You Use warnings; other minor fixes (NFC).
Per Zachary Turner and Mehdi Amini suggestion to make only post-commit reviews.

llvm-svn: 287838
2016-11-23 23:16:32 +00:00
Greg Clayton 6f6e4dbd5d Improve DWARF parsing speed by improving DWARFAbbreviationDeclaration
This patch gets a DWARF parsing speed improvement by having DWARFAbbreviationDeclaration instances know if they have a fixed byte size. If an abbreviation has a fixed byte size that can be calculated given a DWARFUnit, then parsing a DIE becomes two steps: parse ULEB128 abbrev code, and then add constant size to the offset.

This patch also adds a fixed byte size to each DWARFAbbreviationDeclaration::AttributeSpec so that attributes can quickly skip their values if needed without the need to lookup the fixed for size.

Notable improvements:

- DWARFAbbreviationDeclaration::findAttributeIndex() now returns an Optional<uint32_t> instead of a uint32_t and we no longer have to look for the magic -1U return value
- Optional<uint32_t> DWARFAbbreviationDeclaration::findAttributeIndex(dwarf::Attribute attr) const;
- DWARFAbbreviationDeclaration now has a getAttributeValue() function that extracts an attribute value given a DIE offset that takes advantage of the DWARFAbbreviationDeclaration::AttributeSpec::ByteSize
- bool DWARFAbbreviationDeclaration::getAttributeValue(const uint32_t DIEOffset, const dwarf::Attribute Attr, const DWARFUnit &U, DWARFFormValue &FormValue) const;
- A DWARFAbbreviationDeclaration instance can return a fixed byte size for itself so DWARF parsing is faster:
- Optional<size_t> DWARFAbbreviationDeclaration::getFixedAttributesByteSize(const DWARFUnit &U) const;
- Any functions that used to take a "const DWARFUnit *U" that would crash if U was NULL now take a "const DWARFUnit &U" and are only called with a valid DWARFUnit

Differential Revision: https://reviews.llvm.org/D26567

llvm-svn: 286924
2016-11-15 01:23:06 +00:00
Adrian Prantl c4fbbcf9ed Import/update constants from the DWARF 5 public review draft document.
https://reviews.llvm.org/D26051

llvm-svn: 285421
2016-10-28 17:59:50 +00:00
David Blaikie e438cff475 llvm-symbolizer: Avoid infinite recursion walking dwos where the dwo contains a dwo_name attribute
The dwo_name was added to dwo files to improve diagnostics in dwp, but
it confuses tools that attempt to load any dwo named by a dwo_name, even
ones inside dwos. Avoid this by keeping track of whether a unit is
already a dwo unit, and if so, not loading further dwos.

llvm-svn: 267241
2016-04-22 22:50:56 +00:00
David Blaikie 9a4f3cb275 llvm-symbolizer: prefer .dwo contents over fission-gmlt-like-data when .dwo file is present
Rather than relying on the gmlt-like data emitted into the .o/executable
which only contains the simple name of any inlined functions, use the
.dwo file if present.

Test symbolication with/without a .dwo, and the old test that was
testing behavior when no gmlt-like data was present. (I haven't included
a test of non-gmlt-like data + no .dwo (that would be akin to
symbolication with no debug info) but we could add one for completeness)

The test was simplified a bit to be a little clearer (unoptimized, force
inline, using a function call as the inlined entity) and regenerated
with ToT clang. For the no-gmlt-like-data case, I modified Clang back to
its old behavior temporarily & the .dwo file is identical so it is
shared between the two executables.

llvm-svn: 267227
2016-04-22 21:32:59 +00:00
Kevin Enderby 3fcdf6ae2a Thread Expected<...> up from createMachOObjectFile() to allow llvm-objdump to produce a real error message
Produce the first specific error message for a malformed Mach-O file describing
the problem instead of the generic message for object_error::parse_failed of
"Invalid data was encountered while parsing the file”.  Many more good error
messages will follow after this first one.

This is built on Lang Hames’ great work of adding the ’Error' class for
structured error handling and threading Error through MachOObjectFile
construction.  And making createMachOObjectFile return Expected<...> .

So to to get the error to the llvm-obdump tool, I changed the stack of
these methods to also return Expected<...> :

  object::ObjectFile::createObjectFile()
  object::SymbolicFile::createSymbolicFile()
  object::createBinary()

Then finally in ParseInputMachO() in MachODump.cpp the error can
be reported and the specific error message can be printed in llvm-objdump
and can be seen in the existing test case for the existing malformed binary
but with the updated error message.

Converting these interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now use of
errorToErrorCode() and errorOrToExpected() are used where the callers
are yet to be converted.

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(ObjOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there is one fix also needed to lld/COFF/InputFiles.cpp that goes along
with this that I will commit right after this.  So expect lld not to built
after this commit and before the next one.

llvm-svn: 265606
2016-04-06 22:14:09 +00:00
David Blaikie 4689ef5943 Fix null dereference committed in r253277
llvm-svn: 253393
2015-11-17 22:39:26 +00:00
David Blaikie 35c2eebfe4 dwarfdump: support indexed string dumping in dwp based on the STR_OFFSETS component of the index
llvm-svn: 253392
2015-11-17 22:39:23 +00:00
David Blaikie c4e2bed738 dwarfdump: Reference the appropriate line table segment when dumping dwp files
Also improves .dwo type unit dumping which didn't handle this either.

llvm-svn: 253377
2015-11-17 21:08:05 +00:00
David Blaikie 82641be467 dwarfdump: Use the index to find the right abbrev offset in DWP files
llvm-svn: 253277
2015-11-17 00:39:55 +00:00
Benjamin Kramer 68a29562f9 Refactor: Simplify boolean conditional return statements in llvm/lib/DebugInfo/DWARF
Use clang-tidy to simplify boolean conditional return statements. Patch by
Richard Thomson <legalize@xmission.com>!

Differential Revision: http://reviews.llvm.org/D9972

llvm-svn: 238132
2015-05-25 13:28:03 +00:00
Alexey Samsonov 7a18c06128 [DWARF parser] Make DWARF parser more robust against missing compile/type units.
DWARF standard claims that each compilation/type unit header in
.debug_info/.debug_types section must be followed by corresponding
compile/type unit DIE, possibly with its children. Two situations
are possible:

 * compile/type unit DIE is missing because DWARF producer failed to
   emit it.
 * DWARF parser failed to parse unit DIE correctly, for instance if it
   contains some unsupported attributes (see r237721, for instance).

In either of these cases, the library, and the tools that use it
(llvm-dwarfdump, llvm-symbolizer) should not crash. Insert appropriate
checks to protect against this.

llvm-svn: 237733
2015-05-19 21:54:32 +00:00
Zachary Turner 6489d7b949 Move DIContext.h to common DebugInfo location.
This will enable us to create a PDBContext so as to expose some
amount of debug info functionality through a common interace.

Differential Revision: http://reviews.llvm.org/D9205
Reviewed by: Alexey Samsonov

llvm-svn: 235612
2015-04-23 17:37:47 +00:00
Zachary Turner 82af9438d0 Move DebugInfo to DebugInfo/DWARF.
In preparation for adding PDB support to LLVM, this moves the
DWARF parsing code to its own subdirectory under DebugInfo, and
renames LLVMDebugInfo to LLVMDebugInfoDWARF.

This is purely a mechanical / build system change.

Differential Revision: http://reviews.llvm.org/D7269
Reviewed by: Eric Christopher

llvm-svn: 227586
2015-01-30 18:07:45 +00:00