Commit Graph

2160 Commits

Author SHA1 Message Date
Jan Kratochvil ba8907bf6f [nfc] llvm-dwarfdump: DWARFAbbreviationDeclaration::AttributeSpec -> DWARFAttribute
`AttributeSpec` does not contain values while `DWARFAttribute` already
does. Therefore one no longer needs to pass `uint64_t *OffsetPtr`.

Differential Revision: https://reviews.llvm.org/D98194
2021-03-09 08:31:23 +01:00
Rafael Auler 7a3e664db5 [DebugInfo] Do not error on unsupported CIE version
D81469 introduced a check to error on CIE version different
than 1 for eh_frame, but older compilers mistakenly create binaries
with this version set to 3 for DWARF4 or 4 to DWARF5. Move the check
to dump time instead of eh_frame parse time, so we can be tolerant
with older binaries.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D97830
2021-03-08 19:39:08 -08:00
Nico Weber 301551ae8e [PDB] Fix unsigned integer overflow
When building with -fsanitize=unsigned-integer-overflow, this code
causes a diagnostic like:

    ../../llvm/lib/DebugInfo/PDB/Native/GSIStreamBuilder.cpp:159:15:
    runtime error: unsigned integer overflow:
    90 - 229 cannot be represented in type 'unsigned long'

unsigned integer overflow is well defined and it isn't an issue in
practice, but in obscure scenarios (S1.size() small, S2.size over 2GB
on 32-bit systems) it could even be a bug.

So use the usual idiom for implementing cmp functions instead of the
gernally considered buggy idiom :)
See e.g. https://www.gnu.org/software/libc/manual/html_node/Comparison-Functions.html
or https://stackoverflow.com/questions/10996418/efficient-integer-compare-function/10997428#10997428

Differential Revision: https://reviews.llvm.org/D97557
2021-02-26 11:26:53 -05:00
Fangrui Song a7ceef9254 DebugInfo/Symbolize: Exclude ARM mapping symbols for .symtab symbolization after D95916
Their names don't convey much information, so they should be excluded.
The behavior matches addr2line.

Differential Revision: https://reviews.llvm.org/D96617
2021-02-12 11:04:20 -08:00
Scott Linder 12999d749d [Symbolize] Teach symbolizer to work directly on object file.
This patch intended to provide additional interface to LLVMsymbolizer
such that they work directly on object files. There is an existing
method - symbolizecode which takes an object file, this patch provides
similar overloads for symbolizeInlinedCode, symbolizeData,
symbolizeFrame. This can be useful for clients who already have a
in-memory object files to symbolize for.

Patch By: pvellien (praveen velliengiri)

Reviewed By: scott.linder

Differential Revision: https://reviews.llvm.org/D95232
2021-02-12 18:26:24 +00:00
Fangrui Song 0fd7c31a09 DebugInfo/Symbolize: Use stable_sort
This fixes coff-dwarf.test on some build bots.
The test relies on the sort order and prefers main (StorageClass: External) to .text (StorageClass: Static).
2021-02-11 22:53:56 -08:00
Fangrui Song 92ee3dd95d DebugInfo/Symbolize: Don't differentiate function/data symbolization
Before d08bd13ac8, only `SymbolRef::ST_Function`
symbols were used for .symtab symbolization. That commit added a `"DATA"` mode
to llvm-symbolizer which used `SymbolRef::ST_Data` symbols for symbolization.

Since function and data symbols have different addresses, we don't need to
differentiate the two modes. This patches unifies the two modes to simplify
code.

`"DATA"` is used by `compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp`.
`check-hwasan` and `check-tsan` have runtime tests.

Differential Revision: https://reviews.llvm.org/D96322
2021-02-11 19:22:44 -08:00
Adrian Prantl 97dbab8797 llvm-dwarfdump: fix the counting when printing DW_OP_entry_value
The block size is in bytes, and not number of operands.

Differential Revision: https://reviews.llvm.org/D96472
2021-02-11 11:17:04 -08:00
Fangrui Song 04a2e12612 DebugInfo/Symbolize: Retrieve filename from the preceding STT_FILE for .symtab symbolization
The ELF spec says:

> STT_FILE: Conventionally, the symbol's name gives the name of the source file associated with the object file. A file symbol has STB_LOCAL binding, its section index is SHN_ABS, and it precedes the other STB_LOCAL symbols for the file, if it is present.

For a local symbol, the preceding STT_FILE symbol is almost always in the same
file[1]. GNU addr2line uses this heuristic to retrieve the filename associated
with a local symbol (e.g. internal linkage functions in C/C++).

GNU addr2line can assign STT_FILE filename to a non-local symbol, too, but the trick
only works if no regular symbol precede STT_FILE. This patch does not implement this corner case
(not useful for most executables which have more than one files).

In case of filename mismatch between .debug_line & .symtab, arbitrarily make .debug_line win.

[1]: LLD does not synthesize STT_FILE symbols
(https://bugs.llvm.org/show_bug.cgi?id=48023 see also
https://sourceware.org/bugzilla/show_bug.cgi?id=26822).  An assembly file
without `.file` directives can cause mis-attribution. This is an edge case.

Differential Revision: https://reviews.llvm.org/D95927
2021-02-10 09:47:10 -08:00
Fangrui Song 6d766c8bf9 DebugInfo/Symbolize: Allow STT_NOTYPE/STT_GNU_IFUNC symbols for .symtab symbolization
In assembly files, omitting `.type foo,@function` is common. Such functions have
type `STT_NOTYPE` and llvm-symbolizer reports `??` for them.

An ifunc symbol usually has an associated resolver symbol which is defined at
the same address. Returning either one is fine for symbolization. The resolver
symbol may not end up in the symbol table if (object file) `.L` is used (linked
image) .symtab is stripped while .dynsym is retained.

This patch allows ELF STT_NOTYPE/STT_GNU_IFUNC symbols for .symtab symbolization.

I have left TODO in the test files for an unimplemented STT_FILE heuristic.

Differential Revision: https://reviews.llvm.org/D95916
2021-02-08 12:29:11 -08:00
Wouter van Oortmerssen e3c0b0fe09 [WebAssembly] locals can now be indirect in DWARF
This for example to indicate that byval args are represented by a pointer to a struct.
Followup to https://reviews.llvm.org/D94140

Differential Revision: https://reviews.llvm.org/D94347
2021-02-05 11:14:42 -08:00
Yang Fan e5f258cb03
[NFC][DebugInfo] Fix Wreturn-type gcc warning
GCC warning:
```
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp: In member function ‘llvm::Expected<long unsigned int> llvm::dwarf::CFIProgram::Instruction::getOperandAsUnsigned(const llvm::dwarf::CFIProgram&, uint32_t) const’:
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp:425:1: warning: control reaches end of non-void function [-Wreturn-type]
  425 | }
      | ^
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp: In member function ‘llvm::Expected<long int> llvm::dwarf::CFIProgram::Instruction::getOperandAsSigned(const llvm::dwarf::CFIProgram&, uint32_t) const’:
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp:477:1: warning: control reaches end of non-void function [-Wreturn-type]
  477 | }
      | ^
```
2021-01-29 11:42:23 +08:00
Greg Clayton f8122d3532 Add the ability to extract the unwind rows from DWARF Call Frame Information.
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
2021-01-28 13:39:17 -08:00
Reid Kleckner bacf9cf2c5 Revert "[PDB] Defer relocating .debug$S until commit time and parallelize it"
This reverts commit 1a9bd5b813.

I suspect that this patch may have caused https://crbug.com/1171438.
2021-01-28 13:17:27 -08:00
David Blaikie 4318028cd2 DebugInfo: Add a DWARF FORM extension for addrx+offset references to reduce relocations
This is an alternative to the use of complex DWARF expressions for
addresses - shaving off a few extra bytes of expression overhead.
2021-01-28 10:20:02 -08:00
Simon Pilgrim 7396f720f9 [DebugInfo] Remove some unused includes. NFCI.
Mainly removing a lot of <vector> includes from files that don't explicitly use std::vector
2021-01-28 11:21:35 +00:00
Kazu Hirata 0da15ea581 [llvm] Use append_range (NFC) 2021-01-27 23:25:41 -08:00
Kazu Hirata 16baad8f4e [llvm] Use pop_back_val (NFC) 2021-01-24 12:18:57 -08:00
Kazu Hirata 551aaa24af [llvm] Use isDigit (NFC) 2021-01-21 19:59:50 -08:00
Kazu Hirata 6de4865545 [llvm] Use hasSingleElement (NFC) 2021-01-20 21:35:55 -08:00
Reid Kleckner 1a9bd5b813 Reland "[PDB] Defer relocating .debug$S until commit time and parallelize it"
This reverts commit 5b7aef6eb4 and relands
6529d7c5a4.

The ASan error was debugged and determined to be the fault of an invalid
object file input in our test suite, which was fixed by my last change.
LLD's project policy is that it assumes input objects are valid, so I
have added a comment about this assumption to the relocation bounds
check.
2021-01-20 11:53:43 -08:00
Kazu Hirata b023cdeacc [llvm] Use llvm::all_of (NFC) 2021-01-19 20:19:17 -08:00
Mitch Phillips 5b7aef6eb4 Revert "[PDB] Defer relocating .debug$S until commit time and parallelize it"
This reverts commit 6529d7c5a4.

Reason: Broke the ASan buildbots.
http://lab.llvm.org:8011/#/builders/99/builds/1567
2021-01-19 11:45:48 -08:00
Kazu Hirata 352fcfc697 [llvm] Use llvm::sort (NFC) 2021-01-17 10:39:45 -08:00
Reid Kleckner 6529d7c5a4 [PDB] Defer relocating .debug$S until commit time and parallelize it
This is a pretty classic optimization. Instead of processing symbol
records and copying them to temporary storage, do a first pass to
measure how large the module symbol stream will be, and then copy the
data into place in the PDB file. This requires defering relocation until
much later, which accounts for most of the complexity in this patch.

This patch avoids copying the contents of all live .debug$S sections
into heap memory, which is worth about 20% of private memory usage when
making PDBs. However, this is not an unmitigated performance win,
because it can be faster to read dense, temporary, heap data than it is
to iterate symbol records in object file backed memory a second time.

Results on release chrome.dll:
peak mem: 5164.89MB -> 4072.19MB (-1,092.7MB, -21.2%)
wall-j1:  0m30.844s -> 0m32.094s (slightly slower)
wall-j3:  0m20.968s -> 0m20.312s (slightly faster)
wall-j8:  0m19.062s -> 0m17.672s (meaningfully faster)

I gathered similar numbers for a debug, component build of content.dll
in Chrome, and the performance impact of this change was in the noise.
The memory usage reduction was visible and similar.

Because of the new parallelism in the PDB commit phase, more cores makes
the new approach faster. I'm assuming that most C++ developer machines
these days are at least quad core, so I think this is a win.

Differential Revision: https://reviews.llvm.org/D94267
2021-01-12 17:46:29 -08:00
Kazu Hirata 9850d3b10a [CodeGen, DebugInfo] Use llvm::find_if (NFC) 2021-01-10 09:24:53 -08:00
Simon Pilgrim 028091195d [DWARF] DWARFDebugLoc::dumpRawEntry - remove dead stores. NFCI.
Don't bother zeroing local (unused) variables just before returning.

Fixes clang static analyzer warning.
2021-01-07 12:53:28 +00:00
Kazu Hirata cd088ba7e6 [llvm] Use llvm::lower_bound and llvm::upper_bound (NFC) 2021-01-05 21:15:59 -08:00
Kazu Hirata 0edbc90ec5 [DebugInfo] Use llvm::append_range (NFC) 2021-01-04 11:42:45 -08:00
Nico Weber c8dedfe269 fix typos to cycle bots 2021-01-01 22:58:40 -05:00
Amy Huang 7e13694ac7 [llvm-symbolizer][Windows] Add start line when searching in line table sections.
Fixes issue where if a line section doesn't start with a line number
then the addresses at the beginning of the section don't have line numbers.

For example, for a line section like this
```
  0001:00000010-00000014, line/column/addr entries = 1
     7 00000013 !
```
a line number wouldn't be found for addresses from 10 to 12.

This matches behavior when using the DIA SDK.

Differential Revision: https://reviews.llvm.org/D93306
2020-12-17 07:57:36 -08:00
Nico Weber cf16437e05 fix typos to cycle bots 2020-12-12 20:19:33 -05:00
Georgii Rymar ffbce65f95 [lib/Object, tools] - Make ELFObjectFile::getELFFile return reference.
We always have an object, so we don't have to return a pointer.

Differential revision: https://reviews.llvm.org/D92560
2020-12-04 16:02:29 +03:00
Amy Huang efd1ec0dec Recommit "[llvm-symbolizer] Switch to using native symbolizer by default on Windows"
This reverts commit 1b63177a56.
2020-11-30 17:36:12 -08:00
Amy Huang 00bbef2bb2 [llvm-symbolizer] Fix native symbolization on windows for inline sites.
The existing code handles this correctly and I checked that the code
in NativeInlineSiteSymbol also handles this correctly, but it was
wrong in the NativeFunctionSymbol code.

Differential Revision: https://reviews.llvm.org/D92134
2020-11-30 14:27:35 -08:00
Amy Huang 1b63177a56 Revert "[llvm-symbolizer] Switch to using native symbolizer by default on Windows"
Breaks some asan tests on the buildbot.

This reverts commit c74b427cb2.
2020-11-23 16:29:45 -08:00
Amy Huang c74b427cb2 [llvm-symbolizer] Switch to using native symbolizer by default on Windows
llvm-symbolizer used to use the DIA SDK for symbolization on
Windows; this patch switches to using native symbolization, which was
implemented recently.

Users can still make the symbolizer use DIA by adding the `-dia` flag
in the LLVM_SYMBOLIZER_OPTS environment variable.

Differential Revision: https://reviews.llvm.org/D91814
2020-11-23 15:57:08 -08:00
Amy Huang b4902bcd98 [NFC] remove print statement I accidentally added. 2020-11-23 10:51:09 -08:00
Georgii Rymar 9a99d23a1b [lib/Object] - Generalize the RelocationResolver API.
This allows to reuse the RelocationResolver from the code
that doesn't want to deal with `RelocationRef` class.

I am going to use it in llvm-readobj. See the description
of D91530 for more details.

Differential revision: https://reviews.llvm.org/D91533
2020-11-20 10:32:49 +03:00
Jorge Gorbe Moya 314a0d73a8 Fix crash after looking up dwo_id=0 in CU index.
In the current state, if getFromHash(0) is called and there's no CU with
dwo_id=0, the lookup will stop at an empty slot, then the check
`Rows[H].getSignature() != S` won't cause the lookup to fail and return
a nullptr (as it should), because the empty slot has a 0 in the
signature field, and a pointer to the empty slot will be incorrectly
returned.

This patch fixes this by using the index field in the hash entry to
check for empty slots: signature = 0 can match a valid hash but
according to the spec the index for an occupied slot will always be
non-zero.

Differential Revision: https://reviews.llvm.org/D91670
2020-11-19 11:15:01 -08:00
Amy Huang bc98034040 [llvm-symbolizer] Add inline stack traces for Windows.
This adds inline stack frames for symbolizing on Windows.

Differential Revision: https://reviews.llvm.org/D88988
2020-11-17 13:19:13 -08:00
serge-sans-paille 9218ff50f9 llvmbuildectomy - replace llvm-build by plain cmake
No longer rely on an external tool to build the llvm component layout.

Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.

These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.

Differential Revision: https://reviews.llvm.org/D90848
2020-11-13 10:35:24 +01:00
David Truby 81b96bb6f1 [Aarch64] Fix assumption that Windows implies x86
When compiling for Windows on Arm the amd64 debug interfce from the Visual
Studio SDK is used as the cmake currently only distinguishes between x86 and
amd64 by checking the pointer size. Instead we can get the target
architecture for the compilier and check that to distinguish between
architectures.
2020-10-30 12:11:34 +00:00
Amy Huang 7669f3c0f6 Recommit "[CodeView] Emit static data members as S_CONSTANTs."
We used to only emit static const data members in CodeView as
S_CONSTANTS when they were used; this patch makes it so they are always emitted.

This changes CodeViewDebug.cpp to find the static const members from the
class debug info instead of creating DIGlobalVariables in the IR
whenever a static const data member is used.

Bug: https://bugs.llvm.org/show_bug.cgi?id=47580

Differential Revision: https://reviews.llvm.org/D89072

This reverts commit 504615353f.
2020-10-28 16:35:59 -07:00
Amy Huang 504615353f Revert "[CodeView] Emit static data members as S_CONSTANTs."
Seems like there's an assert in here that we shouldn't be running into.

This reverts commit 515973222e.
2020-10-27 11:29:58 -07:00
Amy Huang 515973222e [CodeView] Emit static data members as S_CONSTANTs.
We used to only emit static const data members in CodeView as
S_CONSTANTS when they were used; this patch makes it so they are always emitted.

I changed CodeViewDebug.cpp to find the static const members from the
class debug info instead of creating DIGlobalVariables in the IR
whenever a static const data member is used.

Bug: https://bugs.llvm.org/show_bug.cgi?id=47580

Differential Revision: https://reviews.llvm.org/D89072
2020-10-26 15:30:35 -07:00
David Blaikie 0ec5baa132 llvm-dwarfdump: Support verbose printing DW_OP_convert to print the CU local offset before the resolved absolute offset 2020-10-23 18:50:15 -07:00
David Blaikie a67d164a82 Revert several changes related to llvm-symbolizer exiting non-zero on failure.
Seems users have enough different uses of the symbolizer where they
might have unknown binaries and offsets such that "best effort" behavior
is all that's expected of llvm-symbolizer - so even erroring on unknown
executables and out of bounds offsets might not be suitable.

This reverts commit 1de0199748.
This reverts commit a7b209a6d4.
This reverts commit 338dd138ea.
2020-10-21 15:21:44 -07:00
Luqman Aden 51892a42da [COFF][ARM] Fix CodeView for Windows on 32bit ARM targets.
Create the LLVM / CodeView register mappings for the 32-bit ARM Window targets.

Reviewed By: compnerd

Differential Revision: https://reviews.llvm.org/D89622
2020-10-19 22:16:16 -07:00
David Blaikie a7b209a6d4 llvm-symbolizer: Exit non-zero when DWARF parsing errors have been rendered 2020-10-14 23:42:00 -07:00
David Blaikie 9670a45c98 libDebugInfoDWARF: Don't try to parse loclist[.dwo] headers when parsing debug_info[.dwo]
There's no way to know whether there's a loclist contribution to parse
if there's no loclistx encoding - and if there is one, there's no need
to walk back from the loclist_base (or, uin the case of
info.dwo/loclist.dwo - starting at 0 in the contribution) to parse the
header, instead rely on the DWARF32/64 and address size in the CU
that's already available.

This would come up in split DWARF (non-split wouldn't try to read a
loclist header in the absence of a loclist_base) when one unit had
location lists and another does not (because the loclists.dwo section
would be non-empty in that case - in the case where it's empty the
parsing would silently skip).

Simplify the testing a bit, rather than needing a whole dwp, etc - by
creating a malformed loclists.dwo section (and use single file Split
DWARF) that would trip up any attempt to parse it - but no attempt
should be made.
2020-10-13 22:28:59 -07:00
Greg Clayton a4b842e294 Show register names in DWARF unwind info.
Register context information was already being passed into the DWARFDebugFrame code that dumps unwind information but it wasn't being used. This change adds the ability to dump registers names of a valid MC register context was passed in and if it knows about the register. Updated the tests to use the newly returned register names.

Differential Revision: https://reviews.llvm.org/D88767
2020-10-05 15:34:33 -07:00
David Blaikie 6d0be74af5 llvm-dwarfdump: Don't try to parse rnglist tables when dumping CUs
It's not possible to do this in complete generality - a CU using a
sec_offset DW_AT_ranges has no way of knowing where its rnglists
contribution starts, so should not attempt to parse any full rnglist
table/header to do so. And even using FORM_rnglistx there's no need to
parse the header - the offset can be computed using the CU's DWARF
format (32 or 64) to compute offset entry sizes, and then the list
parsed at that offset without ever trying to find a rnglist contribution
header immediately prior to the rnglists_base.
2020-10-04 19:18:14 -07:00
David Blaikie 92c45e4ee2 llvm-dwarfdump: Add support for DW_RLE_startx_endx 2020-10-04 17:50:43 -07:00
David Blaikie 628a319475 llvm-dwarfdump: Print addresses in debug_line to the parsed address size 2020-10-04 16:05:49 -07:00
David Blaikie ea83e0b17e llvm-dwarfdump: Dump address forms in their encoded length rather than always in 64 bits
Few places did this already - refactor them all into a common helper.
2020-10-04 15:48:57 -07:00
David Blaikie 8036cf7f54 llvm-dwarfdump: Skip tombstoned address ranges
Make the dumper & API a bit more informative by using the new tombstone
addresses to filter out or otherwise render more explicitly dead code
ranges.
2020-10-04 13:43:29 -07:00
Reid Kleckner 5519e4da83 Re-land "[PDB] Merge types in parallel when using ghashing"
Stored Error objects have to be checked, even if they are success
values.

This reverts commit 8d250ac3cd.
Relands commit 49b3459930655d879b2dc190ff8fe11c38a8be5f..

Original commit message:
-----------------------------------------

This makes type merging much faster (-24% on chrome.dll) when multiple
threads are available, but it slightly increases the time to link (+10%)
when /threads:1 is passed. With only one more thread, the new type
merging is faster (-11%). The output PDB should be identical to what it
was before this change.

To give an idea, here is the /time output placed side by side:
                              BEFORE    | AFTER
  Input File Reading:           956 ms  |  968 ms
  Code Layout:                  258 ms  |  190 ms
  Commit Output File:             6 ms  |    7 ms
  PDB Emission (Cumulative):   6691 ms  | 4253 ms
    Add Objects:               4341 ms  | 2927 ms
      Type Merging:            2814 ms  | 1269 ms  -55%!
      Symbol Merging:          1509 ms  | 1645 ms
    Publics Stream Layout:      111 ms  |  112 ms
    TPI Stream Layout:          764 ms  |   26 ms  trivial
    Commit to Disk:            1322 ms  | 1036 ms  -300ms
----------------------------------------- --------
Total Link Time:               8416 ms    5882 ms  -30% overall

The main source of the additional overhead in the single-threaded case
is the need to iterate all .debug$T sections up front to check which
type records should go in the IPI stream. See fillIsItemIndexFromDebugT.
With changes to the .debug$H section, we could pre-calculate this info
and eliminate the need to do this walk up front. That should restore
single-threaded performance back to what it was before this change.

This change will cause LLD to be much more parallel than it used to, and
for users who do multiple links in parallel, it could regress
performance. However, when the user is only doing one link, it's a huge
improvement. In the future, we can use NT worker threads to avoid
oversaturating the machine with work, but for now, this is such an
improvement for the single-link use case that I think we should land
this as is.

Algorithm
----------

Before this change, we essentially used a
DenseMap<GloballyHashedType, TypeIndex> to check if a type has already
been seen, and if it hasn't been seen, insert it now and use the next
available type index for it in the destination type stream. DenseMap
does not support concurrent insertion, and even if it did, the linker
must be deterministic: it cannot produce different PDBs by using
different numbers of threads. The output type stream must be in the same
order regardless of the order of hash table insertions.

In order to create a hash table that supports concurrent insertion, the
table cells must be small enough that they can be updated atomically.
The algorithm I used for updating the table using linear probing is
described in this paper, "Concurrent Hash Tables: Fast and General(?)!":
https://dl.acm.org/doi/10.1145/3309206

The GHashCell in this change is essentially a pair of 32-bit integer
indices: <sourceIndex, typeIndex>. The sourceIndex is the index of the
TpiSource object, and it represents an input type stream. The typeIndex
is the index of the type in the stream. Together, we have something like
a ragged 2D array of ghashes, which can be looked up as:
  tpiSources[tpiSrcIndex]->ghashes[typeIndex]

By using these side tables, we can omit the key data from the hash
table, and keep the table cell small. There is a cost to this: resolving
hash table collisions requires many more loads than simply looking at
the key in the same cache line as the insertion position. However, most
supported platforms should have a 64-bit CAS operation to update the
cell atomically.

To make the result of concurrent insertion deterministic, the cell
payloads must have a priority function. Defining one is pretty
straightforward: compare the two 32-bit numbers as a combined 64-bit
number. This means that types coming from inputs earlier on the command
line have a higher priority and are more likely to appear earlier in the
final PDB type stream than types from an input appearing later on the
link line.

After table insertion, the non-empty cells in the table can be copied
out of the main table and sorted by priority to determine the ordering
of the final type index stream. At this point, item and type records
must be separated, either by sorting or by splitting into two arrays,
and I chose sorting. This is why the GHashCell must contain the isItem
bit.

Once the final PDB TPI stream ordering is known, we need to compute a
mapping from source type index to PDB type index. To avoid starting over
from scratch and looking up every type again by its ghash, we save the
insertion position of every hash table insertion during the first
insertion phase. Because the table does not support rehashing, the
insertion position is stable. Using the array of insertion positions
indexed by source type index, we can replace the source type indices in
the ghash table cells with the PDB type indices.

Once the table cells have been updated to contain PDB type indices, the
mapping for each type source can be computed in parallel. Simply iterate
the list of cell positions and replace them with the PDB type index,
since the insertion positions are no longer needed.

Once we have a source to destination type index mapping for every type
source, there are no more data dependencies. We know which type records
are "unique" (not duplicates), and what their final type indices will
be. We can do the remapping in parallel, and accumulate type sizes and
type hashes in parallel by type source.

Lastly, TPI stream layout must be done serially. Accumulate all the type
records, sizes, and hashes, and add them to the PDB.

Differential Revision: https://reviews.llvm.org/D87805
2020-09-30 15:44:38 -07:00
Reid Kleckner 8d250ac3cd Revert "[PDB] Merge types in parallel when using ghashing"
This reverts commit 49b3459930.
2020-09-30 14:55:32 -07:00
Reid Kleckner 49b3459930 [PDB] Merge types in parallel when using ghashing
This makes type merging much faster (-24% on chrome.dll) when multiple
threads are available, but it slightly increases the time to link (+10%)
when /threads:1 is passed. With only one more thread, the new type
merging is faster (-11%). The output PDB should be identical to what it
was before this change.

To give an idea, here is the /time output placed side by side:
                              BEFORE    | AFTER
  Input File Reading:           956 ms  |  968 ms
  Code Layout:                  258 ms  |  190 ms
  Commit Output File:             6 ms  |    7 ms
  PDB Emission (Cumulative):   6691 ms  | 4253 ms
    Add Objects:               4341 ms  | 2927 ms
      Type Merging:            2814 ms  | 1269 ms  -55%!
      Symbol Merging:          1509 ms  | 1645 ms
    Publics Stream Layout:      111 ms  |  112 ms
    TPI Stream Layout:          764 ms  |   26 ms  trivial
    Commit to Disk:            1322 ms  | 1036 ms  -300ms
----------------------------------------- --------
Total Link Time:               8416 ms    5882 ms  -30% overall

The main source of the additional overhead in the single-threaded case
is the need to iterate all .debug$T sections up front to check which
type records should go in the IPI stream. See fillIsItemIndexFromDebugT.
With changes to the .debug$H section, we could pre-calculate this info
and eliminate the need to do this walk up front. That should restore
single-threaded performance back to what it was before this change.

This change will cause LLD to be much more parallel than it used to, and
for users who do multiple links in parallel, it could regress
performance. However, when the user is only doing one link, it's a huge
improvement. In the future, we can use NT worker threads to avoid
oversaturating the machine with work, but for now, this is such an
improvement for the single-link use case that I think we should land
this as is.

Algorithm
----------

Before this change, we essentially used a
DenseMap<GloballyHashedType, TypeIndex> to check if a type has already
been seen, and if it hasn't been seen, insert it now and use the next
available type index for it in the destination type stream. DenseMap
does not support concurrent insertion, and even if it did, the linker
must be deterministic: it cannot produce different PDBs by using
different numbers of threads. The output type stream must be in the same
order regardless of the order of hash table insertions.

In order to create a hash table that supports concurrent insertion, the
table cells must be small enough that they can be updated atomically.
The algorithm I used for updating the table using linear probing is
described in this paper, "Concurrent Hash Tables: Fast and General(?)!":
https://dl.acm.org/doi/10.1145/3309206

The GHashCell in this change is essentially a pair of 32-bit integer
indices: <sourceIndex, typeIndex>. The sourceIndex is the index of the
TpiSource object, and it represents an input type stream. The typeIndex
is the index of the type in the stream. Together, we have something like
a ragged 2D array of ghashes, which can be looked up as:
  tpiSources[tpiSrcIndex]->ghashes[typeIndex]

By using these side tables, we can omit the key data from the hash
table, and keep the table cell small. There is a cost to this: resolving
hash table collisions requires many more loads than simply looking at
the key in the same cache line as the insertion position. However, most
supported platforms should have a 64-bit CAS operation to update the
cell atomically.

To make the result of concurrent insertion deterministic, the cell
payloads must have a priority function. Defining one is pretty
straightforward: compare the two 32-bit numbers as a combined 64-bit
number. This means that types coming from inputs earlier on the command
line have a higher priority and are more likely to appear earlier in the
final PDB type stream than types from an input appearing later on the
link line.

After table insertion, the non-empty cells in the table can be copied
out of the main table and sorted by priority to determine the ordering
of the final type index stream. At this point, item and type records
must be separated, either by sorting or by splitting into two arrays,
and I chose sorting. This is why the GHashCell must contain the isItem
bit.

Once the final PDB TPI stream ordering is known, we need to compute a
mapping from source type index to PDB type index. To avoid starting over
from scratch and looking up every type again by its ghash, we save the
insertion position of every hash table insertion during the first
insertion phase. Because the table does not support rehashing, the
insertion position is stable. Using the array of insertion positions
indexed by source type index, we can replace the source type indices in
the ghash table cells with the PDB type indices.

Once the table cells have been updated to contain PDB type indices, the
mapping for each type source can be computed in parallel. Simply iterate
the list of cell positions and replace them with the PDB type index,
since the insertion positions are no longer needed.

Once we have a source to destination type index mapping for every type
source, there are no more data dependencies. We know which type records
are "unique" (not duplicates), and what their final type indices will
be. We can do the remapping in parallel, and accumulate type sizes and
type hashes in parallel by type source.

Lastly, TPI stream layout must be done serially. Accumulate all the type
records, sizes, and hashes, and add them to the PDB.

Differential Revision: https://reviews.llvm.org/D87805
2020-09-30 14:22:48 -07:00
David Blaikie 0328feb086 DebugInfo: Filter DWARFv5 TUs out of the debug_info unit list when CUs requested
Since DWARFv5 places TUs in debug_info, some of DWARFContext's APIs have
become a bit erroneous, including TUs in the CU list by accident.
Correct that by providing compile_units (& dwo_compile_units) that
filter out the type units from the debug_info units.

Differential Revision: https://reviews.llvm.org/D87935
2020-09-23 22:15:53 -07:00
Jonas Devlieghere e1ef7183c6 [dwarfdump] Warn for tags with DW_CHILDREN_yes but no children.
Flag DIEs that have DW_CHILDREN_yes set in their abbreviation but don't
actually have any children.

rdar://59809554

Differential revision: https://reviews.llvm.org/D88048
2020-09-23 22:12:04 -07:00
David Blaikie ad68a8b952 DebugInfo: Cleanup RLE dumping, using a length-constrained DataExtractor rather than carrying the end offset separately 2020-09-18 19:32:38 -07:00
David Blaikie 51a505340d DebugInfo: Simplify line table parsing to take all the units together, rather than CUs and TUs separately 2020-09-18 11:18:23 -07:00
David Blaikie e0802fe016 DebugInfo: Tidy up initializing multi-section contributions in DWARFContext 2020-09-18 10:54:43 -07:00
Simon Pilgrim ed53ff4cde SymbolizableObjectFile.h - remove unnecessary includes. NFCI.
Use forward declarations where possible, move includes down to SymbolizableObjectFile.cpp and avoid duplicate includes.
2020-09-17 13:18:53 +01:00
Reid Kleckner e47d2927de Include (Type|Symbol)Record.h less
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.
2020-09-16 09:59:03 -07:00
Petr Hosek 9c73e55510 Revert "[DebugInfo] Remove dots from getFilenameByIndex return value"
This is failing on Windows bots due to path separator normalization.

This reverts commit 042c235068.
2020-09-15 10:06:47 -07:00
Petr Hosek 042c235068 [DebugInfo] Remove dots from getFilenameByIndex return value
When concatenating directory with filename in getFilenameByIndex, we
might end up with a path that contains extra dots. For example, if the
input is /path and ./example, we would return /path/./example. Run
sys::path::remove_dots on the output to eliminate unnecessary dots.

Differential Revision: https://reviews.llvm.org/D87657
2020-09-14 20:19:06 -07:00
David Blaikie 69da27c749 llvm-symbolizer: Add optional "start file" to match "start line"
Since a function might have portions of its code coming from multiple
different files, "start line" is ambiguous (it can't just be resolved
relative to the file/line specified). Add start file to disambiguate it.
2020-09-08 15:40:58 -07:00
Xing GUO 67ce11405b [llvm-dwarfdump] Warn user when it encounters no null terminated strings.
When llvm-dwarfdump encounters no null terminated strings, we should
warn user about it rather than ignore it and print nothing.

Before this patch, when llvm-dwarfdump dumps a .debug_str section whose
content is "abc", it prints:

```
.debug_str contents:
```

After this patch:

```
.debug_str contents:
warning: no null terminated string at offset 0x0
```

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D86998
2020-09-03 08:49:57 +08:00
Xing GUO 369f9169a5 [DebugInfo] Simplify string table dumpers.
This patch adds a helper function DumpStrSection to simplify codes.
Besides, nonprintable chars in debug_str and debug_str.dwo sections
are printed as escaped chars.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D86918
2020-09-02 08:41:10 +08:00
Jordan Rupprecht 202766947e [NFC] Fix unused var in release builds.
This was always unused, but the change in D86354 upgraded this to a compiler warning.
2020-09-01 16:38:24 -07:00
David Blaikie f7a49d2aa6 [WIP][DebugInfo] Lazily parse debug_loclist offsets
Parsing DWARFv5 debug_loclist offsets when a CU is parsed is weighing
down memory usage of symbolizers that don't need to parse this data at
all. There's not much benefit to caching these anyway - since they are
O(1) lookup and reading once you know where the offset list starts (and
can do bounds checking with the offset list size too).

In general, I think it might be time to start paying down some of the
technical debt of loc/loclist/range/rnglist parsing to try to unify it a
bit more.

eg:

* Currently DWARFUnit has: RangeSection, RangeSectionBase, LocSection,
  LocSectionBase, LocTable, RngListTable, LoclistTableHeader (be nice if
  these were all wrapped up in two variables - one for loclists, one for
  rnglists)

* rnglists and loclists are handled differently (see:
  LoclistTableHeader, but no RnglistTableHeader)

* maybe all these types could be less stateful - lazily parse what they
  need to, even reparsing rather than caching because it doesn't seem
  too expensive, for instance. (though admittedly so long as it's
  constantcost/overead per compilatiton that's probably adequate)

* Maybe implementing and using a DWARFDataExtractor that can be
  sub-ranged (so we could slice it up to just the single contribution) -
  though maybe that's not so useful because loc/ranges need to refer to
  it by absolute, not contribution-relative mechanisms

Differential Revision: https://reviews.llvm.org/D86110
2020-08-18 10:49:39 -07:00
Igor Kudrin 95fad44e34 [DebugInfo] Avoid an infinite loop with a truncated pre-v5 .debug_str_offsets.dwo.
dumpStringOffsetsSection() expects the size of a contribution to be
correctly aligned. The patch adds the corresponding verifications for
pre-v5 cases.

Differential Revision: https://reviews.llvm.org/D85739
2020-08-14 13:11:37 +07:00
Igor Kudrin 9ceb192e14 [llvm-dwarfdump] Avoid crashing if an abbreviation offset is invalid.
Note that DWARFUnit::getAbbreviations() returns nullptr if the
abbreviations could not be read, but callers used the returned
pointer without checking.

Differential Revision: https://reviews.llvm.org/D85738
2020-08-12 16:01:53 +07:00
David Stenberg 91bd9db2cd [DebugInfo] Allow GNU macro extension to be read
Allow the GNU .debug_macro extension to be parsed and printed by
llvm-dwarfdump. In an upcoming patch support will be added for emitting
that format also.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D82974
2020-08-11 13:30:52 +02:00
James Henderson ca05601cd2 [DebugInfo] Don't error for zero-length arange entries
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 cb3a598c87, 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
2020-08-10 14:57:52 +01:00
Nico Weber bc5d68dd8a Revert "[DebugInfo] Don't error for zero-length arange entries"
This reverts commit cb3a598c87.
Breaks build of check-llvm dep obj2yaml everywhere.
2020-08-10 08:20:35 -04:00
James Henderson cb3a598c87 [DebugInfo] Don't error for zero-length arange entries
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
2020-08-10 12:48:31 +01:00
Raphael Isemann 1de43bd6df Revert "PDBExtras.h - remove unnecessary raw_ostream forward declaration. NFCI."
This reverts commit 87c5437afd.

The commit includes several headers in the middle of a function, which
breaks pretty much everything.
2020-08-06 15:15:43 +02:00
Simon Pilgrim 87c5437afd PDBExtras.h - remove unnecessary raw_ostream forward declaration. NFCI.
We already need to include raw_ostream.h, also add missing StringRef.h and cstdint implicit dependencies.

Remove unnecessary includes from PDBExtras.cpp
2020-08-06 11:28:42 +01:00
Greg Clayton e1de85f9f4 Add verification for DW_AT_decl_file and DW_AT_call_file.
LTO builds have been creating invalid DWARF and one of the errors was a file index that was out of bounds. "llvm-dwarfdump --verify" will check all file indexes for line tables already, but there are no checks for the validity of file indexes in attributes.

The verification will verify if there is a DW_AT_decl_file/DW_AT_call_file that:
- there is a line table for the compile unit
- the file index is valid
- the encoding is appropriate

Tests are added that test all of the above conditions.

Differential Revision: https://reviews.llvm.org/D84817
2020-08-05 15:30:13 -07:00
Amy Huang 724bf4ee23 [Symbolize][PDB] Switch llvm-symbolizer to use PDB_ReaderType::Native.
Since native PDB reading has been implemented for symbolizing,
switch to using the native PDB reader by default, unless
LLVM_ENABLE_DIA_SDK is on.

Bug: https://bugs.llvm.org/show_bug.cgi?id=41795

Differential Revision: https://reviews.llvm.org/D84286
2020-07-22 17:17:57 -07:00
Amy Huang 0881d0bed3 [PDB][NativeSession] Clean up some things in NativeSession.
-Use the actual sect/offset to keep track of symbols in the cache so they don't get created multiple times with different addresses.
-Remove getSymTag from PDBFunctionSymbol/PDBPublicSymbol because it's already implemented in the base class
-Merge the symbolizer test files for DIA and native, since the tests are the same.
-Implement getCompilandId for NativeLineNumber

Reviewed By: amccarth

Differential Revision: https://reviews.llvm.org/D84208
2020-07-21 16:54:52 -07:00
Fangrui Song 3ab0f53ef3 [DebugInfo] Respect relocations when decoding DW_EH_PE_sdata4 & DW_EH_PE_sdata8 and support R_ARM_REL32
The addresses in llvm-dwarfdump --eh-frame output for object files are closer to readelf -wf output now.
2020-07-18 09:00:50 -07:00
Igor Kudrin ec9f0c7d4a [DebugInfo] Fix a possible crash when reading a malformed .debug_*lists section.
DWARFListTableHeader::length() handles the zero value of HeaderData.Length
in a special way, which makes the result different from the calculated
value of FullLength, which leads to triggering an assertion. The patch
moves the assertion a bit later when `FullLength` is already checked for
minimal allowed value.

Differential Revision: https://reviews.llvm.org/D82886
2020-07-14 16:35:17 +07:00
Oliver Stannard 57909b0a53 [llvm-objdump] Add entry_value and stack_value opcodes
Add the DW_OP_entry_value and DW_OP_stack_value opcodes to the DWARF
expression printer.

Differential revision: https://reviews.llvm.org/D74843
2020-07-14 10:24:59 +01:00
Oliver Stannard 1d7311e052 [llvm-objdump] Add simple memory expressions to variable display
Add the DW_OP_breg0..DW_OP_breg31 and DW_OP_bregx opcodes to the DWARF
expression printer.

Differential revision: https://reviews.llvm.org/D74841
2020-07-14 10:24:59 +01:00
Alexandre Ganea 23cd70d71c [PDB] Fix out-of-bounds acces when sorting GSI buckets
When building in Debug on Windows-MSVC after b7402edce3, a lot of tests were failing because we were dereferencing an element past the end of HashRecords. This happened towards the end of the table, in unused slots.
2020-07-10 10:55:27 -04:00
Benjamin Kramer d36b8414bd [DebugInfo] Fix pessimizing move. NFC.
DWARFDebugPubTable.cpp:80:31: warning: moving a temporary object prevents copy elision [-Wpessimizing-move]
2020-07-09 14:23:46 +02:00
Igor Kudrin ca4d8da0c3 [DebugInfo] Add more checks to parsing .debug_pub* sections.
The patch adds checking for various potential issues in parsing name
lookup tables and reporting them as recoverable errors, similarly as we
do for other tables.

Differential Revision: https://reviews.llvm.org/D83050
2020-07-09 19:15:31 +07:00
Igor Kudrin 68f5a8b204 [DebugInfo] Do not hang when parsing a malformed .debug_pub* section.
The parsing method did not check reading errors and might easily fall
into an infinite loop on an invalid input because of that.

Differential Revision: https://reviews.llvm.org/D83049
2020-07-09 19:15:11 +07:00
Oliver Stannard dc4a6f5db4 [llvm-objdump] Display locations of variables alongside disassembly
This adds the --debug-vars option to llvm-objdump, which prints
locations (registers/memory) of source-level variables alongside the
disassembly based on DWARF info. A vertical line is printed for each
live-range, with a label at the top giving the variable name and
location, and the position and length of the line indicating the program
counter range in which it is valid.

Differential revision: https://reviews.llvm.org/D70720
2020-07-09 09:58:00 +01:00
Georgii Rymar bee8cdcabd [DebugInfo/DWARF] - Test invalid CFI opcodes properly and refine related `CFIProgram::parse` code.
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
2020-07-08 12:10:23 +03:00
Amy Huang 9ee90a4905 [NativeSession] Add column numbers to NativeLineNumber.
Summary:
This adds column numbers if they are present, and otherwise
sets the column number to be zero.

Bug: https://bugs.llvm.org/show_bug.cgi?id=41795

Reviewers: amccarth

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81950
2020-07-07 09:59:22 -07:00
James Henderson 9e09a54c69 [DebugInfo] Use Cursor to detect errors in debug line prologue parser
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
2020-07-03 11:52:06 +01:00
Reid Kleckner b7402edce3 [PDB] Defer public serialization until PDB writing
This reduces peak memory on my test case from 1960.14MB to 1700.63MB
(-260MB, -13.2%) with no measurable impact on CPU time. I'm currently
working with a publics stream that is about 277MB. Before this change,
we would allocate 277MB of heap memory, serialize publics into them,
hold onto that heap memory, open the PDB, and commit into it.  After
this change, we defer the serialization until commit time.

In the last change I made to public writing, I re-sorted the list of
publics multiple times in place to avoid allocating new temporary data
structures. Deferring serialization until later requires that we don't
reorder the publics. Instead of sorting the publics, I partially
construct the hash table data structures, store a publics index in them,
and then sort the hash table data structures. Later, I replace the index
with the symbol record offset.

This change also addresses a FIXME and moves the list of global and
public records from GSIHashStreamBuilder to GSIStreamBuilder. Now that
publics aren't being serialized, it makes even less sense to store them
as a list of CVSymbol records. The hash table used to deduplicate
globals is moved as well, since that is specific to globals, and not
publics.

Reviewed By: aganea, hans

Differential Revision: https://reviews.llvm.org/D81296
2020-06-30 11:28:04 -07:00
Georgii Rymar 1e820e82b1 [DebugInfo/DWARF] - Do not hang when CFI are truncated.
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
2020-06-23 14:39:24 +03:00
James Henderson 9782c922cb [DebugInfo] Print line table extended opcode bytes if parsing fails
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
2020-06-23 10:04:02 +01:00