This (partially) fixes a regression introduced by
https://reviews.llvm.org/D43945 / r327399, which parallelized
DwarfLinker. This patch avoids parsing and allocating the memory for
all input DIEs up front and instead only allocates them in the
concurrent loop in the AnalyzeLambda. At the end of the loop the
memory from the LinkContext is cleared again.
This reduces the peak memory needed to link the debug info of a
non-modular build of the Swift compiler by >3GB.
rdar://problem/43444464
Differential Revision: https://reviews.llvm.org/D51078
llvm-svn: 340650
Both DWARFDebugLine and DWARFDebugAddr used the same callback mechanism
for handling recoverable errors. They both implemented similar warn() function
to be used as such callbacks.
In this revision we get rid of code duplication and move this warn() function
to DWARFContext as DWARFContext::dumpWarning().
Reviewers: lhames, jhenderson, aprantl, probinson, dblaikie, JDevlieghere
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D51033
llvm-svn: 340528
The functions `lookForDIEsToKeep` and `keepDIEAndDependencies` can have
some very deep recursion. This tackles part of this problem by removing
the recursion from `lookForDIEsToKeep` by turning it into a worklist.
The difficulty in doing so is the computation of incompleteness, which
depends on the incompleteness of its children. To compute this, we
insert "continuation markers" into the worklist. This informs the work
loop to (re)compute the incompleteness property of the DIE associated
with it (i.e. the parent of the previously processed DIE).
This patch should generate byte-identical output. Unfortunately it also
has some impact of performance, regressing by about 4% when processing
clang on my machine.
Differential revision: https://reviews.llvm.org/D48899
llvm-svn: 338536
This patch add support for emitting DWARF5 accelerator tables
(.debug_names) from dsymutil. Just as with the Apple style accelerator
tables, it's possible to update existing dSYMs. This patch includes a
test that show how you can convert back and forth between the two types.
If no kind of table is specified, dsymutil will default to generating
Apple-style accelerator tables whenever it finds those in its input. The
same is true when there are no accelerator tables at all. Finally, in
the remaining case, where there's at least one DWARF v5 table and no
Apple ones, the output will contains a DWARF accelerator tables
(.debug_names).
Differential revision: https://reviews.llvm.org/D49137
llvm-svn: 337980
When implementing the DWARF accelerator tables in dsymutil I ran into an
assertion in the assembler. Debugging these kind of issues is a lot
easier when looking at the assembly instead of debugging the assembler
itself. Since it's only a matter of creating an AsmStreamer instead of a
MCObjectStreamer it made sense to turn this into a (hidden) dsymutil
feature.
Differential revision: https://reviews.llvm.org/D49079
llvm-svn: 336561
The original binary holder has an optimization where it caches a static
library (archive) between consecutive calls to GetObjects. However, the
actual memory buffer wasn't cached between calls.
This made sense when dsymutil was processing objects one after each
other, but when processing them in parallel, several binaries have to be
in memory at the same time. For this reason, every link context
contained a binary holder.
Having one binary holder per context is problematic, because the same
static archive was cached for every object file. Luckily, when the file
is mmap'ed, this was only costing us virtual memory.
This patch introduces a new BinaryHolder variant that is fully cached,
for all the object files it load, as well as the static archives. This
way, we don't have to give up on this optimization of bypassing the
file system.
Differential revision: https://reviews.llvm.org/D48501
llvm-svn: 335990
This patch splits off some abstractions used by dsymutil's dwarf linker
and moves them into separate header and implementation files. This
almost halves the number of LOC in DwarfLinker.cpp and makes it a lot
easier to understand what functionality lives where.
Differential revision: https://reviews.llvm.org/D48647
llvm-svn: 335749
Errors found processing the DW_AT_ranges attribute are propagated by lower level
routines and reported by their callers.
Reviewer: JDevlieghere
Differential Revision: https://reviews.llvm.org/D48344
llvm-svn: 335188
Change the "recoverable" error callback to take an Error instaed of a
string.
Reviewed by: JDevlieghere
Differential Revision: https://reviews.llvm.org/D46831
llvm-svn: 332845
The idea is that a client that wants split dwarf would create a
specific kind of object writer that creates two files, and use it to
create the streamer.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47050
llvm-svn: 332749
Reviewed by: dblaikie, JDevlieghere, espindola
Differential Revision: https://reviews.llvm.org/D44560
Summary:
The .debug_line parser previously reported errors by printing to stderr and
return false. This is not particularly helpful for clients of the library code,
as it prevents them from handling the errors in a manner based on the calling
context. This change switches to using llvm::Error and callbacks to indicate
what problems were detected during parsing, and has updated clients to handle
the errors in a location-specific manner. In general, this means that they
continue to do the same thing to external users. Below, I have outlined what
the known behaviour changes are, relating to this change.
There are two levels of "errors" in the new error mechanism, to broadly
distinguish between different fail states of the parser, since not every
failure will prevent parsing of the unit, or of subsequent unit. Malformed
table errors that prevent reading the remainder of the table (reported by
returning them) and other minor issues representing problems with parsing that
do not prevent attempting to continue reading the table (reported by calling a
specified callback funciton). The only example of this currently is when the
last sequence of a unit is unterminated. However, I think it would be good to
change the handling of unrecognised opcodes to report as minor issues as well,
rather than just printing to the stream if --verbose is used (this would be a
subsequent change however).
I have substantially extended the DwarfGenerator to be able to handle
custom-crafted .debug_line sections, allowing for comprehensive unit-testing
of the parser code. For now, I am just adding unit tests to cover the basic
error reporting, and positive cases, and do not currently intend to test every
part of the parser, although the framework should be sufficient to do so at a
later point.
Known behaviour changes:
- The dump function in DWARFContext now does not attempt to read subsequent
tables when searching for a specific offset, if the unit length field of a
table before the specified offset is a reserved value.
- getOrParseLineTable now returns a useful Error if an invalid offset is
encountered, rather than simply a nullptr.
- The parse functions no longer use `WithColor::warning` directly to report
errors, allowing LLD to call its own warning function.
- The existing parse error messages have been updated to not specifically
include "warning" in their message, allowing consumers to determine what
severity the problem is.
- If the line table version field appears to have a value less than 2, an
informative error is returned, instead of just false.
- If the line table unit length field uses a reserved value, an informative
error is returned, instead of just false.
- Dumping of .debug_line.dwo sections is now implemented the same as regular
.debug_line sections.
- Verbose dumping of .debug_line[.dwo] sections now prints the prologue, if
there is a prologue error, just like non-verbose dumping.
As a helper for the generator code, I have re-added emitInt64 to the
AsmPrinter code. This previously existed, but was removed way back in r100296,
presumably because it was dead at the time.
This change also requires a change to LLD, which will be committed separately.
llvm-svn: 331971
Create convenience functions for printing error, warning and note to
stdout. Previously we had similar functions being used in dsymutil, but
given that this pattern is so common it makes sense to make it available
globally.
llvm-svn: 330091
These aren't the .def style files used in LLVM that require a macro
defined before their inclusion - they're just basic non-modular includes
to stamp out command line flag variables.
llvm-svn: 329840
With the threading refactoring, loading of object files happens before
checking whether we're dealing with a swift AST. While that's not an
issue per se, it causes a warning to be printed:
warning: /path/to/a.swiftmodule: The file was not recognized as a valid object file
note: while processing /path/to/a.swiftmodule
This suppresses the warning by checking for a Swift AST before
attempting to load is as an object file.
rdar://39240444
llvm-svn: 329553
The DwarfLinker can have some very deep recursion that can max out the
(significantly smaller) stack when using threads. We don't want this
limitation when we only have a single thread. We already have this
workaround for the architecture-related threading. This patch applies
the same workaround to the parallel analysis and cloning.
Differential revision: https://reviews.llvm.org/D45172
llvm-svn: 329093
When running dsymutil as part of your build system, it can be desirable
for warnings to be part of the end product, rather than just being
emitted to the output stream. This patch upstreams that functionality.
Differential revision: https://reviews.llvm.org/D44639
llvm-svn: 328965
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.
Reviewers: JDevlieghere, zturner, echristo, dberris, friss
Reviewed By: echristo
Subscribers: gbedwell, llvm-commits
Differential Revision: https://reviews.llvm.org/D45141
llvm-svn: 328943
This is a follow-up to r327137 where we unified error handling for the
DwarfLinker. This replaces calls to errs() and outs() with the
appropriate ostream wrapper everywhere in dsymutil.
llvm-svn: 327411
This patch makes dsymutil perform analyzeContextInfo and CloneDIEs in
parallel. For the same object file, there is a dependency between the
two. However, we can do analyzeContextInfo for the next object file
while cloning DIEs for the current. This is exactly the approach taken
in this patch.
For WebCore, this leads to a performance improvement of 29% and for
clang we see similar results with at 32% improvement.
A big thanks to Pete Cooper who came up with the original idea and
the PoC.
Differential revision: https://reviews.llvm.org/D43945
llvm-svn: 327399
This patch introduces the LinkContext which is necessary to have
dsymutil perform analysis and cloning of DIEs in parallel. As requested
in D43945, I'm landing this as two separate commits.
llvm-svn: 327382
We improved the handling of errors and warnings in dwarfdump's verifier
in rL314498. This patch does the same thing for dsymutil.
Differential revision: https://reviews.llvm.org/D44052
llvm-svn: 327137
The DwarfLinker implementation is already relatively large with over 4k
LOC. This commit moves the implementation of NonRelocatableStringpool
into a separate cpp file.
llvm-svn: 326425
Following DW_AT_sibling attributes completely defeats the pruning pass.
Although clang doesn't generate the DW_AT_sibling attribute we should
still handle it correctly.
Differential revision: https://reviews.llvm.org/D43439
llvm-svn: 326231
Calling realpath is expensive but necessary to perform the uniqueing in
dsymutil. Although we already cached the results for every individual
file in the line table, we had reports of it taking 40 seconds of a 3.5
minute link.
This patch adds a second level of caching. When we do have to call
realpath, we cache its result for its parents path. We didn't replace
the existing caching, because it's fast (indexed) and saves us from
reading the line table for entries we've already seen.
For WebkitCore this results in a decrease of 11% in linking time: from
85.79 to 76.11 seconds (average over 3 runs).
Differential revision: https://reviews.llvm.org/D43511
llvm-svn: 325757
This patch contains logic for handling DW_TAG_label that's present in
darwin's dsymutil implementation, but not yet upstream.
Differential revision: https://reviews.llvm.org/D43438
llvm-svn: 325600
Summary:
This commit separates the abstract accelerator table data structure
from the code for writing out an on-disk representation of a specific
accelerator table format. The idea is that former (now called
AccelTable<T>) can be reused for the DWARF v5 accelerator tables
as-is, without any further customizations.
Some bits of the emission code (now living in the EmissionContext class)
can be reused for DWARF v5 as well, but the subtle differences in the
layout of various subtables mean the sharing is not always possible.
(Also, the individual emit*** functions are fairly simple so there's a
tradeoff between making a bigger general-purpose function, and two
smaller targeted functions.)
Another advantage of this setup is that more of the serialization logic
can be hidden in the .cpp file -- I have moved declarations of the
header and all the emission functions there.
Reviewers: JDevlieghere, aprantl, probinson, dblaikie
Subscribers: echristo, clayborg, vleschuk, llvm-commits
Differential Revision: https://reviews.llvm.org/D43285
llvm-svn: 325516
This commit attempts to re-land the r324480 which was reverted in
r324493 because it broke the Windows bots. For now I disabled the two
update tests on Windows until I'm able to debug this.
Differential revision: https://reviews.llvm.org/D42880
llvm-svn: 324592
Now that dsymutil can generate accelerator tables, we can upstream the
update logic that, as the name implies, updates the accelerator tables
in an existing dSYM bundle. In combination with `-minimize` this can be
used to remove redundant .debug_(inlines|pubtypes|pubnames).
Differential revision: https://reviews.llvm.org/D42880
llvm-svn: 324480
r323476 added support for DW_FORM_line_strp, and incorrectly made that
depend on having a DWARFUnit available. We shouldn't be tracking
.debug_line_str in DWARFUnit after all. After this patch, I can do an
NFC follow up and undo a bunch of the "plumbing" part of r323476.
Differential Revision: https://reviews.llvm.org/D42609
llvm-svn: 323691
This patch adds support for generating accelerator tables in dsymutil.
This feature was already present in our internal repository but not yet
upstreamed because it requires changes to the Apple accelerator table
implementation.
Differential revision: https://reviews.llvm.org/D42501
llvm-svn: 323655
This is needed in order to use our StringPool entries in the Apple
accelerator tables.
As this is NFC we rely on the existing tests for correctness.
llvm-svn: 323339
Currently it's not possible to access MCSubtargetInfo from a TgtMCAsmBackend.
D20830 threaded an MCSubtargetInfo reference through
MCAsmBackend::relaxInstruction, but this isn't the only function that would
benefit from access. This patch removes the Triple and CPUString arguments
from createMCAsmBackend and replaces them with MCSubtargetInfo.
This patch just changes the interface without making any intentional
functional changes. Once in, several cleanups are possible:
* Get rid of the awkward MCSubtargetInfo handling in ARMAsmBackend
* Support 16-bit instructions when valid in MipsAsmBackend::writeNopData
* Get rid of the CPU string parsing in X86AsmBackend and just use a SubtargetFeature for HasNopl
* Emit 16-bit nops in RISCVAsmBackend::writeNopData if the compressed instruction set extension is enabled (see D41221)
This change initially exposed PR35686, which has since been resolved in r321026.
Differential Revision: https://reviews.llvm.org/D41349
llvm-svn: 321692
This patch removes the hard-coded check for DWARFv2 line tables. Now
dsymutil accepts line tables for DWARF versions 2 to 5 (inclusive).
Differential revision: https://reviews.llvm.org/D41084
rdar://35968319
llvm-svn: 320469
This moves the file handling out of DwarfLinker.cpp.
This fixes what is at least an oddity if not a bug. DwarfLinker.cpp
was using ToolOutputFile, which uses RemoveFileOnSignal. The issue is
that dsymutil.cpp uses that too. It is now clear from the interface
that only dsymutil.cpp is responsible for creating and deleting files.
llvm-svn: 318334
Adrian Prantl