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
This lays the foundation for dumping types not referenced by DW_AT_type
attributes (in the near-term, that'll be DW_AT_containing_type for a
DW_TAG_ptr_to_member_type - in the future, potentially dumping the
pretty printed name next to the DW_TAG for the type, rather than only
when the type is referenced from elsewhere)
llvm-svn: 348961
When there is no .debug_addr section for some reason,
llvm-dwarfdump would print the bogus empty section name when dumping ranges
in .debug_info:
DW_AT_ranges [DW_FORM_rnglistx] (indexed (0x0) rangelist = 0x00000004
[0x0000000000000000, 0x0000000000000001) ""
[0x0000000000000000, 0x0000000000000002) "")
That happens because of the code which uses 0 (zero) as a section index as a default value.
The code should use -1ULL instead because technically 0 is a valid zero section index
in ELF and -1ULL is a special constant used that means "no section available".
This is mostly a fix for the overall correctness/safety of the code,
but a test case is provided too.
Differential revision: https://reviews.llvm.org/D55113
llvm-svn: 348115
Especially for symbolizer it can be efficient to have to search through
the entire index when it isn't needed - llvm-symbolizer looks up only a
few CUs & already has an index available in getUnitForEntry, once it's
passed down to DWARFUnitHeader::extract then there's no need for it to
call getFromOffset.
llvm-svn: 347134
This is a follow-up to r346715. Use PRIx64 to formatted print of 64-bit
value in the `DWARFDebugLoclists::LocationList::dump` to escape problem
on big-endian hosts.
llvm-svn: 347049
The `DWARFDebugAddrTable::dump` routine prints 32/64-bits addresses.
These values are stored in a vector of `uint64_t` independently of their
original sizes. But `format` function gets format string with PRIx32
suffix in case of 32-bit address size. At least on MIPS 32-bit targets
that leads to incorrect output.
This patch changes formats strings and always use PRIx64 to print
`uint64_t` values.
Differential Revision: http://reviews.llvm.org/D54424
llvm-svn: 346715
This was being used as a sort of indirect out parameter from shouldDump
- seems simpler to use it as the actual result of the call. (this does
mean using a pointer to an Optional & actually using all 3 states (null,
None, and present) which is, admittedly, a tad subtle - but given the
limited scope, seems OK to me - open to discussion though, if others
feel strongly about it)
llvm-svn: 346691
Summary: The debug_info_offset values in .debug_{,gnu_}pub{name,types} may be relocated. Change it to DWARFSection so that we can get relocated values.
Reviewers: ruiu, dblaikie, grimar, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D54375
llvm-svn: 346615
Adding functionality to the DWARF verifier for DWARF v5 strx* forms which
index into the string offsets table.
Differential Revision: https://reviews.llvm.org/D54049
llvm-svn: 346061
The purpose of this patch is twofold:
- Fold pre-DWARF v5 functionality into v5 to eliminate the need for 2 different
versions of range list handling. We get rid of DWARFDebugRangelist{.cpp,.h}.
- Templatize the handling of range list tables so that location list handling
can take advantage of it as well. Location list and range list tables have the
same basic layout.
A non-NFC version of this patch was previously submitted with r342218, but it caused
errors with some TSan tests. This patch has no functional changes. The difference to
the non-NFC patch is that there are no changes to rangelist dumping in this patch.
Differential Revision: https://reviews.llvm.org/D53545
llvm-svn: 345546
Relocatable content may have overlapping ranges until the sections are
finalized. This reduces the amount of verification that is done on an object
file so that invalid errors are not raised.
llvm-svn: 345441
As was already mentioned in comments for D53364, DWARF 5
spec says about DW_LLE_startx_length:
"This is a form of bounded location description that has two unsigned ULEB operands.
The first value is an address index (into the .debug_addr section) that indicates the beginning of the address range
over which the location is valid. The second value is the length of the range. ")
Currently, the length is always parsed as U32.
Patch change the behavior to parse DW_LLE_startx_length as ULEB128 for DWARF 5
and keeps it as U32 for DWARF4+(pre-DWARF5) for compatibility.
Differential revision: https://reviews.llvm.org/D53564
llvm-svn: 345254
This teaches llvm-dwarfdump to dump the content of .debug_loclists sections.
It converts the DWARFDebugLocDWO class to DWARFDebugLoclists,
teaches llvm-dwarfdump about .debug_loclists section and
adds the implementation for parsing the DW_LLE_offset_pair entries.
Differential revision: https://reviews.llvm.org/D53364
llvm-svn: 344895
Putting addresses in the address pool, even with non-fission, can reduce
relocations - reusing the addresses from debug_info and debug_rnglists
(the latter coming soon)
llvm-svn: 344834