I don't think we have to aim for precise bug compatibility.
We can return a nullptr if a section is consumed by the linker, and
the rest should naturally work.
llvm-svn: 316817
DSO is short for dynamic shared object, so the function name was a
little confusing because it sounded like it didn't work when we were
a creating statically-linked executable or something.
What we mean by "DSO" here is the current output file that we are
creating. Thus the new name. Alternatively, we could call it the current
ELF module, but "module" is a overloaded word, so I avoided that.
llvm-svn: 316809
The Android relocation packing format is a more compact
format for dynamic relocations in executables and DSOs
that is based on delta encoding and SLEBs. An overview
of the format can be found in the Android source code:
https://android.googlesource.com/platform/bionic/+/refs/heads/master/tools/relocation_packer/src/delta_encoder.h
This patch implements relocation packing using that format.
This implementation uses a more intelligent algorithm for compressing
relative relocations than Android's own relocation packer. As a
result it can generally create smaller relocation sections than
that packer. If I link Chromium for Android targeting ARM32 I get a
.rel.dyn of size 174693 bytes, as compared to 371832 bytes with gold
and the Android packer.
Differential Revision: https://reviews.llvm.org/D39152
llvm-svn: 316775
This is for PR34852.
GCC 8.0 or earlier have a bug that it emits R_386_GOTPC relocations
against _GLOBAL_OFFSET_TABLE for .debug_info. The bug seems to have
been fixed in 2017: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82630,
but we do not want LLD to report errors for such inputs.
In this patch we ignore such relocations.
Differential revision: https://reviews.llvm.org/D38625
llvm-svn: 316761
It was reported (https://reviews.llvm.org/D38724#902841) that when we use
-ffunction-sections --emit-relocs build, REL[A] output section receives the name of first
input section, like .rela.text.first_function_in_text rather than .rela.text.
It is probably not really an issue as sh_info still points to correct target section, but
it does not look clean in output and allows internal section name to leak there,
what at least looks confusing and is not consistent with ld.bfd.
Patch changes this behavior so that target output section name is used as a base.
Differential revision: https://reviews.llvm.org/D39242
llvm-svn: 316760
This moves reporting of garbage collected sections right after
we do GC. That simplifies things.
Differential revision: https://reviews.llvm.org/D39058
llvm-svn: 316759
This change allows Thunks to be added on multiple passes. To do this we must
merge only the thunks added in each pass, and deal with thunks that have
drifted out of range of their callers.
A thunk may end out of range of its caller if enough thunks are added in
between the caller and the thunk. To handle this we create another thunk.
Differential Revision: https://reviews.llvm.org/D34692
llvm-svn: 316754
This change adds initial support for range extension thunks. All thunks must
be created within the first pass so some corner cases are not supported. A
follow up patch will add support for multiple passes.
With this change the existing tests arm-branch-error.s and
arm-thumb-branch-error.s now no longer fail with an out of range branch.
These have been renamed and tests added for the range extension thunk.
Differential Revision: https://reviews.llvm.org/D34691
llvm-svn: 316752
When an OutputSection is larger than the branch range for a Target we
need to place thunks such that they are always in range of their caller,
and sufficiently spaced to maximise the number of callers that can use
the thunk. We use the simple heuristic of placing the
ThunkSection at intervals corresponding to a target specific branch range.
If the OutputSection is small we put the thunks at the end of the executable
sections.
Differential Revision: https://reviews.llvm.org/D34689
llvm-svn: 316751
Instead of maintaining a map of the std::vector to ThunkSections, record the
ThunkSections directly in InputSectionDescription.
Differential Revision: https://reviews.llvm.org/D37743
llvm-svn: 316750
Previously, EhFrameSection pushes data to EhFrameHdr by calling addFde
function. By making EhFrameHdr pull data from EhFrameSection, we can
eliminate a member from EhFrameHdr.
llvm-svn: 316730
In GNU ld, this option is enabled by default, but can be set
to reduce some warnings.
For lld, ignore the flag (for now); in case linking still succeeds
everything should be fine, if not, it should be clear to the user
what part failed (possibly requiring adjusting the user project
to not rely on this feature), instead of straight out failing due to
an unknown flag.
Differential Revision: https://reviews.llvm.org/D39330
llvm-svn: 316693
When LLD do ICF for 2 identical sections it leaves 2 duplicate entries in .eh_frame
pointing to the same address. After that it fixes .eh_frame_header's header,
so that it says it contains single FDE, though section itself contains 2
(it contains garbage data at tail).
As a result excessive entries in .eh_frame and excessive dummy data in .eh_frame_header
emited to output. Patch fixes that. This is PR34518.
Differential revision: https://reviews.llvm.org/D38998
llvm-svn: 316648
Changes in D38977 expect 'tar' to be found in one of PATH directories.
On Windows, one might opt to use LLVM_LIT_TOOLS_DIR rather than add MSYS
tools directory to the PATH. In that case, tests for lld failed on run.
Differential Revision: https://reviews.llvm.org/D39278
llvm-svn: 316635
IIUC, SizeOfImage is the distance from the end of the last section to
the image base, rounded up to the page size. So the previous code is
wrong.
Should fix https://bugs.llvm.org/show_bug.cgi?id=34949
(It is nice to know that lld is already being used to create Putty
distribution binaries.)
llvm-svn: 316626
Summary:
The COFF linker and the ELF linker have long had similar but separate
Error.h and Error.cpp files to implement error handling. This change
introduces new error handling code in Common/ErrorHandler.h, changes the
COFF and ELF linkers to use it, and removes the old, separate
implementations.
Reviewers: ruiu
Reviewed By: ruiu
Subscribers: smeenai, jyknight, emaste, sdardis, nemanjai, nhaehnle, mgorny, javed.absar, kbarton, fedor.sergeev, llvm-commits
Differential Revision: https://reviews.llvm.org/D39259
llvm-svn: 316624
"/DISCARD/" is a special section name in the linker script to discard
input sections. Previously, we handled it as if it were a real section,
so an input section can be assigned but dead. However, allowing sections
to be
- assigned and alive (will be emitted),
- not assigned and dead (removed), or
- assigned but dead (???)
feels logically wrong and practically error-prone. This patch removes
the last combination of the states.
llvm-svn: 316622
It is PR34946.
Spec (http://man7.org/linux/man-pages/man1/ld.1.html) tells about
--orphan-handling=MODE, option where MODE can be one of four:
"place", "discard", "warn", "error".
Currently we already report orphans when -verbose given,
what becomes excessive with option implemented.
Patch stops reporting orphans when -versbose is given,
and support "place", "warn" and "error" modes.
It is not yet clear that "discard" mode is useful so it is not supported.
Differential revision: https://reviews.llvm.org/D39000
llvm-svn: 316583
This is PR34886.
SUBALIGN command currently triggers failture if result expression
is zero. Patch fixes the issue, treating zero as 1, what is consistent with
other places and ELF spec it seems.
Patch also adds "is power of 2" check for this and other expressions
returning alignment.
Differential revision: https://reviews.llvm.org/D38846
llvm-svn: 316580
If /manifest:embed is enabled we're already creating a resource file
out of these flags and adding it to the linkrepro, and it doesn't
seem worth being able to repro side-by-side manifests.
Includes a test that covers this commit as well as r315948.
Differential Revision: https://reviews.llvm.org/D38975
llvm-svn: 316547
link.exe supports this option to convert warnings into errors, and it's
useful to support in LLD as well.
Differential Revision: https://reviews.llvm.org/D39148
llvm-svn: 316502
LLD's handling of boolean flags is suboptimal:
* All boolean flags have a corresponding `:no` flag to turn the flag
off, and the linker should scan for both the non-suffixed and suffixed
flags (and the last one should win), but right now it only scans for
either the suffixed or non-suffixed flag (depending on the default
flag value).
* The `B` multiclass only allows specifying help text for the suffixed
(`:no`) flag, but for some flags (e.g. `/appcontainer`) the help text
should be associated with the non-suffixed flag instead.
Extend the `B` multiclass to have help text for both non-suffixed and
suffixed flag variants, and alter the existing help text accordingly in
some cases. Scan for both the non-suffixed and suffixed variants in the
driver and set config values accordingly.
This should mostly have no behavior change, apart from the added help
text and the modified argument scanning. Some flags are handled slightly
differently now, however; for example, LLD would previously always treat
64-bit images as large address aware, whereas `/largeaddressaware:no` is
now respected for 64-bit images (which is also how link.exe behaves).
Differential Revision: https://reviews.llvm.org/D39216
llvm-svn: 316501
Rui Ueyama