Note that llvm::support::endianness has been renamed to
llvm::endianness while becoming an enum class as opposed to an
enum. This patch replaces support::{big,little,native} with
llvm::endianness::{big,little,native}.
Note that llvm::support::endianness has been renamed to
llvm::endianness while becoming an enum class as opposed to an enum.
This patch replaces llvm::support::{big,little,native} with
llvm::endianness::{big,little,native}.
CDSort function reordering outperforms the existing default heuristic (
hfsort/C^3) in terms of the performance of generated binaries while
being (almost) as fast. Thus, the suggestion is to change the default.
The speedup is up to 1.5% perf for large front-end binaries, and can be
moderate/neutral for "small" benchmarks.
High-level **perf impact** on two selected binaries:
clang-10 binary (built with LTO+AutoFDO/CSSPGO): wins on top of C^3 in
[0.3%..0.8%]
rocksDB-8 binary (built with LTO+CSSPGO): wins on top of C^3 in
[0.8%..1.5%]
More detailed measurements on the clang binary is at
[here](https://reviews.llvm.org/D152834#4445042)
Integrating MTE globals on Android revealed a lot of cases where
libraries are built as both archives and DSOs, and they're linked into
fully static and dynamic executables respectively.
MTE globals doesn't work for fully static executables. They need a
dynamic loader to process the special R_AARCH64_RELATIVE relocation
semantics with the encoded offset. Fully static executables that had
out-of-bounds derived symbols (like 'int* foo_end = foo[16]') crash
under MTE globals w/ static executables. So, LLD in its current form
simply errors out when you try and compile a fully static executable
that has a single MTE global variable in it.
It seems like a much better idea to simply have LLD not do the special
work for MTE globals in fully static contexts, and to drop any
unnecessary metadata. This means that you can build archives with MTE
globals and link them into both fully-static and dynamic executables.
Treat this as an alias for the --shared option.
In practice in GNU ld, they aren't exact aliases but there are small
subtle differences in what happens and what doesn't, when they are set,
but those differences are probably not intended by users who might be
using the --dll option (which gets passed by -mdll in the compiler
driver), and the differences are within the area where small details
differ between LLD and GNU ld anyway.
Now that llvm::support::endianness has been renamed to
llvm::endianness, we can use the shorter form. This patch replaces
llvm::support::endianness with llvm::endianness.
Some large AVR programs (for devices without long jump) may exceed
128KiB, and lld should give explicit errors other than generate wrong
executables silently.
This adds support for generating Chrome-tracing .json profile traces in
the LLD COFF driver.
Also add the necessary time scopes, so that the profile trace shows in
great detail which tasks are executed.
As an example, this is what we see when linking a Unreal Engine
executable:
For each R_X86_64_(REX_)GOTPCRELX relocation, check that the offset to the symbol is representable with 2^32 signed offset. If not, add a GOT entry for it and set its expr to R_GOT_PC so that we emit the GOT load instead of the relaxed lea. Do this in finalizeAddressDependentContent() where we iteratively attempt this (e.g. RISCV uses this for relaxation, ARM uses this to insert thunks).
Decided not to do the opposite of inserting GOT entries initially and removing them when relaxable because removing GOT entries isn't simple.
One drawback of this approach is that if we see any GOTPCRELX relocation, we'll create an empty .got even if it's not required in the end.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D157020
C++20 will automatically generate an operator== with reversed operand
order, which is ambiguous with the written operator== when one argument
is marked const and the other isn't.
This can happen when manually emitting strings into .drectve sections
with `__attribute__((section(".drectve")))`, which is a way to emulate
`#pragma comment(linker, "...")` for mingw compilers, without requiring
building with -fms-extensions.
Normally, this doesn't generate any comdat, but if compiled with
-fsanitize=address, this section does get turned into a comdat section.
This fixes#67261. This issue can be seen as a regression; a change in
the "lli" tool in 17.x triggers this case, if compiled with ASAN
enabled, triggering this unsupported corner case in LLD. With this
change, LLD can handle it.
Fixes a crash in `-Wl,-emit-relocs` where the linker was not able to
write linker-synthetic absolute symbols to the symbol table.
This change adds a new symbol flag (`WASM_SYMBOL_ABS`), which means that
the symbol's offset is absolute and not relative to a given segment.
Such symbols include `__stack_low` and `__stack_low`.
Note that wasm object files never contains such symbols, only binaries
linked with `-Wl,-emit-relocs`.
Fixes: #67111
Before this patch, with MSVC I was seeing:
```
[304/334] Building CXX object tools\lld\ELF\CMakeFiles\lldELF.dir\InputFiles.cpp.obj
C:\git\llvm-project\lld\ELF\InputFiles.h(327): warning C4661: 'void lld:🧝:ObjFile<llvm::object::ELF32LE>::importCmseSymbols(void)': no suitable definition provided for explicit template instantiation request
C:\git\llvm-project\lld\ELF\InputFiles.h(291): note: see declaration of 'lld:🧝:ObjFile<llvm::object::ELF32LE>::importCmseSymbols'
C:\git\llvm-project\lld\ELF\InputFiles.h(327): warning C4661: 'void lld:🧝:ObjFile<llvm::object::ELF32LE>::redirectCmseSymbols(void)': no suitable definition provided for explicit template instantiation request
C:\git\llvm-project\lld\ELF\InputFiles.h(292): note: see declaration of 'lld:🧝:ObjFile<llvm::object::ELF32LE>::redirectCmseSymbols'
```
This patch removes `redirectCmseSymbols` which is not defined. And it
imports `importCmseSymbols` in InputFiles.cpp, because it is already
explicitly instantiated in ARM.cpp.
When the .eh_frame section is placed at a non-zero
offset within its output section, the relocation
value within .eh_frame are computed incorrectly.
We had similar issue in .ARM.exidx section and it has been
fixed already in https://reviews.llvm.org/D148033.
While applying the relocation using S+A-P, the value
of P (the location of the relocation) is getting wrong.
P is:
P = SecAddr + rel.offset, But SecAddr points to the
starting address of the outputsection rather than the
starting address of the eh frame section within that
output section.
This issue affects all targets which generates .eh_frame
section. Hence fixing in all the corresponding targets it affecting.
Before af744f0b84, the first entry
among the search paths was the empty string, indicating searching
in (or starting from) the current directory. After
af744f0b84, the toolchain/clang
specific lib directories were added at the head of the search path.
This would cause lookups of literal file names or relative paths
to match paths in the toolchain, if there are coincidental files
with similar names there, even if they would be find in the current
directory as well.
Change addClangLibSearchPaths to append to the list like all other
operations on searchPaths - but move the invocation of the
function to the right place in the sequence.
This fixes#67779.
This reverts commit 6403287eff.
This is failing on all but 1 of Linaro's flang builders.
CMake Error at /home/tcwg-buildbot/worker/clang-aarch64-full-2stage/llvm/flang-rt/unittests/CMakeLists.txt:37 (message):
Target llvm_gtest not found.
See discourse thread https://discourse.llvm.org/t/rfc-support-cmake-option-to-control-link-type-built-for-flang-runtime-libraries/71602/18 for full details.
Flang-rt is the new library target for the flang runtime libraries. It builds the Flang-rt library (which contains the sources of FortranRuntime and FortranDecimal) and the Fortran_main library. See documentation in this patch for detailed description (flang-rt/docs/GettingStarted.md).
This patch aims to:
- integrate Flang's runtime into existing llvm infrasturcture so that Flang's runtime can be built similarly to other runtimes via the runtimes target or via the llvm target as an enabled runtime
- decouple the FortranDecimal library sources that were used by both compiler and runtime so that different build configurations can be applied for compiler vs runtime
- add support for running flang-rt testsuites, which were created by migrating relevant tests from `flang/test` and `flang/unittest` to `flang-rt/test` and `flang-rt/unittest`, using a new `check-flang-rt` target.
- provide documentation on how to build and use the new FlangRT runtime
Reviewed By: DanielCChen
Differential Revision: https://reviews.llvm.org/D154869
We are brining a new algorithm for function layout (reordering) based on the
call graph (extracted from a profile data). The algorithm is an improvement of
top of a known heuristic, C^3. It tries to co-locate hot and frequently executed
together functions in the resulting ordering. Unlike C^3, it explores a larger
search space and have an objective closely tied to the performance of
instruction and i-TLB caches. Hence, the name CDS = Cache-Directed Sort.
The algorithm can be used at the linking or post-linking (e.g., BOLT) stage.
Refer to https://reviews.llvm.org/D152834 for the actual implementation of the
reordering algorithm.
This diff adds a linker option to replace the existing C^3 heuristic with CDS.
The new behavior can be turned on by passing "--use-cache-directed-sort".
(the plan is to make it default in a next diff)
**Perf-impact**
clang-10 binary (built with LTO+AutoFDO/CSSPGO): wins on top of C^3 in [0.3%..0.8%]
rocksDB-8 binary (built with LTO+CSSPGO): wins on top of C^3 in [0.8%..1.5%]
Note that function layout affects the perf the most on older machines (with
smaller instruction/iTLB caches) and when huge pages are not enabled. The impact
on newer processors with huge pages enabled is likely neutral/minor.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D152840
Change the FF form --call-graph-profile-sort to --call-graph-profile-sort={none,hfsort}.
This will be extended to support llvm/lib/Transforms/Utils/CodeLayout.cpp.
--call-graph-profile-sort is not used in the wild but
--no-call-graph-profile-sort is (Chromium). Make --no-call-graph-profile-sort an
alias for --call-graph-profile-sort=none.
Reviewed By: rahmanl
Differential Revision: https://reviews.llvm.org/D159544
This patch adds a LLVM_FORCE_VC_REVISION option to force a custom
VC revision to be included instead of trying to fetch one from a
git command. This is helpful in environments where git is not
available or is non-functional but the vc revision is available
through some other means.
Code Object V2 has been deprecated for more than a year now. We can
safely remove it from LLVM.
- [clang] Remove support for the `-mcode-object-version=2` option.
- [lld] Remove/refactor tests that were still using COV2
- [llvm] Update AMDGPUUsage.rst
- Code Object V2 docs are left for informational purposes because those
code objects may still be supported by the runtime/loaders for a while.
- [AMDGPU] Remove COV2 emission capabilities.
- [AMDGPU] Remove `MetadataStreamerYamlV2` which was only used by COV2
- [AMDGPU] Update all tests that were still using COV2 - They are either
deleted or ported directly to code object v4 (as v3 is also planned to
be removed soon).
https://reviews.llvm.org/D48929 updated addends for non-SHF_ALLOC sections
relocated by REL for -r links, but the patch did not update the addends when
--compress-debug-sections={zlib,zstd} is used (#66738).
https://reviews.llvm.org/D116946 handled tombstone values in debug
sections in relocatable links. As a side effect, both
relocateNonAllocForRelocatable (using `sec->relocations`) and
relocatenonNonAlloc (using raw REL/RELA) may run.
Actually, we can adjust the condition in relocatenonAlloc to completely replace
relocateNonAllocForRelocatable. This patch implements this idea and fixes#66738.
As relocateNonAlloc processes the raw relocations like copyRelocations() does,
the condition `if (config->relocatable && type != target.noneRel)` in `copyRelocations`
(commit 08d6a3f133, modified by https://reviews.llvm.org/D62052)
can be made specific to SHF_ALLOC sections.
As a side effect, we can now report diagnostics for PC-relative relocations for
-r. This is a less useful diagnostic that is not worth too much code. As
https://github.com/ClangBuiltLinux/linux/issues/1937 has violations, just
suppress the warning for -r. Tested by commit 561b98f9e0.
The size of .ARM.exidx may shrink across `assignAddress` calls. It is
possible
that the initial iteration has a larger location counter, causing
`__code_size =
__code_end - .; osec : { . += __code_size; }` to report an error, while
the error would
have been suppressed for subsequent `assignAddress` iterations.
Other sections like .relr.dyn may change sizes across `assignAddress`
calls as
well. However, their initial size is zero, so it is difficiult to
trigger a
similar error.
Similar to https://reviews.llvm.org/D152170, postpone the error
reporting.
Fix#66836. While here, add more information to the error message.
The `cp` command will copy the permission bits from the original file to
the new one, which will cause permission denied (no written access) for the
following "echo" command in some system.
Switch to use `cat` which is more robust.
Discussion about this approach: https://discourse.llvm.org/t/rfc-safer-whole-program-class-hierarchy-analysis/65144/18
When enabling WPD in an environment where native binaries are present, types we want to optimize can be derived from inside these native files and devirtualizing them can lead to correctness issues. RTTI can be used as a way to determine all such types in native files and exclude them from WPD providing a safe checked way to enable WPD.
The approach is:
1. In the linker, identify if RTTI is available for all native types. If not, under `--lto-validate-all-vtables-have-type-infos` `--lto-whole-program-visibility` is automatically disabled. This is done by examining all .symtab symbols in object files and .dynsym symbols in DSOs for vtable (_ZTV) and typeinfo (_ZTI) symbols and ensuring there's always a match for every vtable symbol.
2. During thinlink, if `--lto-validate-all-vtables-have-type-infos` is set and RTTI is available for all native types, identify all typename (_ZTS) symbols via their corresponding typeinfo (_ZTI) symbols that are used natively or outside of our summary and exclude them from WPD.
Testing:
ninja check-all
large Meta service that uses boost, glog and libstdc++.so runs successfully with WPD via --lto-whole-program-visibility. Previously, native types in boost caused incorrect devirtualization that led to crashes.
Reviewed By: MaskRay, tejohnson
Differential Revision: https://reviews.llvm.org/D155659
.plt and .branch_lt have the type of SHT_NOBITS and may be relocated by dynamic
relocations with non-zero addends. They should be skipped for the
--check-dynamic-relocations check, as --apply-dynamic-relocs does not apply.
A side effect is that -z rel does not work for the two sections.
Added two --apply-dynamic-relocs --check-dynamic-relocations tests. Also checked
linking a PPC64 clang.
Most targets support --check-dynamic-relocations --apply-dynamic-relocs, so it
makes sense to invert the condition. We want new ports to support
getImplicitAddend.
The import library thunk name suffix uses the stem of the file. We
currently would attempt to trim the suffix by dropping the trailing 4
characters (under the assumption that the output name was `.lib`). This
now uses the `llvm::sys::path` API for computing the stem. This avoids
an assertion failure when the name is less the 4 characters and
assertions are enabled.
like done in the ELF side
this would allow to use archlinux default mingw flags:
`-Wl,-O1,--sort-common,--as-needed -fstack-protector`
(on archlinux packages use the GNU linker by default)
This will make it easy for callers to see issues with and fix up calls
to createTargetMachine after a future change to the params of
TargetMachine.
This matches other nearby enums.
For downstream users, this should be a fairly straightforward
replacement,
e.g. s/CodeGenOpt::Aggressive/CodeGenOptLevel::Aggressive
or s/CGFT_/CodeGenFileType::
Close#57618: currently we align the end of PT_GNU_RELRO to a
common-page-size
boundary, but do not align the end of the associated PT_LOAD. This is
benign
when runtime_page_size >= common-page-size.
However, when runtime_page_size < common-page-size, it is possible that
`alignUp(end(PT_LOAD), page_size) < alignDown(end(PT_GNU_RELRO),
page_size)`.
In this case, rtld's mprotect call for PT_GNU_RELRO will apply to
unmapped
regions and lead to an error, e.g.
```
error while loading shared libraries: cannot apply additional memory protection after relocation: Cannot allocate memory
```
To fix the issue, add a padding section .relro_padding like mold, which
is contained in the PT_GNU_RELRO segment and the associated PT_LOAD
segment. The section also prevents strip from corrupting PT_LOAD program
headers.
.relro_padding has the largest `sortRank` among RELRO sections.
Therefore, it is naturally placed at the end of `PT_GNU_RELRO` segment
in the absence of `PHDRS`/`SECTIONS` commands.
In the presence of `SECTIONS` commands, we place .relro_padding
immediately before a symbol assignment using DATA_SEGMENT_RELRO_END (see
also https://reviews.llvm.org/D124656), if present.
DATA_SEGMENT_RELRO_END is changed to align to max-page-size instead of
common-page-size.
Some edge cases worth mentioning:
* ppc64-toc-addis-nop.s: when PHDRS is present, do not append
.relro_padding
* avoid-empty-program-headers.s: when the only RELRO section is .tbss,
it is not part of PT_LOAD segment, therefore we do not append
.relro_padding.
---
Close#65002: GNU ld from 2.39 onwards aligns the end of PT_GNU_RELRO to
a
max-page-size boundary (https://sourceware.org/PR28824) so that the last
page is
protected even if runtime_page_size > common-page-size.
In my opinion, losing protection for the last page when the runtime page
size is
larger than common-page-size is not really an issue. Double mapping a
page of up
to max-common-page for the protection could cause undesired VM waste.
Internally
we had users complaining about 2MiB max-page-size applying to shared
objects.
Therefore, the end of .relro_padding is padded to a common-page-size
boundary. Users who are really anxious can set common-page-size to match
their runtime page size.
---
17 tests need updating as there are lots of change detectors.
The currently rule places .branch_lt after .data, which does not make
sense. The original contributor probably wanted to place .branch_lt
before .got/.toc, but failed to notice that .got/.toc are RELRO and
placed earlier.
Remove the special case so that .branch_lt is actually closer to .toc,
alleviating the distance issue.
Runnign some tests with asan built of LLD would throw errors similar to the following:
AddressSanitizer:DEADLYSIGNAL
#0 0x55d8e6da5df7 in operator() /mnt/ssd/repo/lld/llvm-project/lld/MachO/Arch/ARM64.cpp:612
#1 0x55d8e6daa514 in operator() /mnt/ssd/repo/lld/llvm-project/lld/MachO/Arch/ARM64.cpp:650
Differential Revision: https://reviews.llvm.org/D157027
Fix#64600: the currently implementation is minimal (see
https://reviews.llvm.org/D83758), and an assignment like
`__TEXT_REGION_ORIGIN__ = DEFINED(__TEXT_REGION_ORIGIN__) ? __TEXT_REGION_ORIGIN__ : 0;`
(used by avr-ld[1]) leads to a value of zero (default value in `declareSymbol`),
which is unexpected.
Assign orders to symbol assignments and references so that
for a script-defined symbol, the `DEFINED` results match users'
expectation. I am unclear about GNU ld's exact behavior, but this hopefully
matches its behavior in the majority of cases.
[1]: https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=ld/scripttempl/avr.sc
When there are multiple catch-all patterns (i.e. a single `*`), GNU ld and gold
select the last pattern. Match their behavior.
This change was inspired by a correction made by Michael Kerrisk to a blog post
I wrote at https://maskray.me/blog/2020-11-26-all-about-symbol-versioning ,
following the current lld rules.
Note: GNU ld prefers global: patterns to local: patterns, which might seem
awkward (https://www.airs.com/blog/archives/300). gold doesn't follow this
behavior, and we do not either.
Linker relaxation may change relocations (offsets and types). However,
when --emit-relocs is used, relocations are simply copied from the input
section causing a mismatch with the corresponding (relaxed) code
section.
This patch fixes this as follows: for non-relocatable RISC-V binaries,
`InputSection::copyRelocations` reads relocations from the relocated
section's `relocations` array (since this gets updated by the relaxation
code). For all other cases, relocations are read from the input section
directly as before.
In order to reuse as much code as possible, and to keep the diff small,
the original `InputSection::copyRelocations` is changed to accept the
relocations as a range of `Relocation` objects. This means that, in the
general case when reading from the input section, raw relocations need
to be converted to `Relocation`s first, which introduces quite a bit of
boiler plate. It also means there's a slight code size increase due to
the extra instantiations of `copyRelocations` (for both range types).
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D159082
Details:
We often use wildcard symbols in the exported_symbols list, and sometimes they match autohide symbols, which triggers these "cannot export hidden symbols" warnings that can be a bit noisy.
It'd be more user-friendly if LLD could truncate these.
Differential Revision: https://reviews.llvm.org/D159095
Issue Details:
When building up line information for CodeView debug info, LLVM attempts to gather the "range" of instructions within a function as these are printed together in a single record. If there is an inlined function, then those lines are attributed to the original function to enable generating `S_INLINESITE` records. However, this thus requires there to be instructions from the inlining function after the inlined function otherwise the instruction range would not include the inlined function.
Fix Details:
Include any inlined functions when finding the extent of a function in `getFunctionLineEntries`
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D159226
The module paths string table mapped to both an id sequentially assigned
during LTO linking, and the module hash. The former is leftover from
before the module hash was added for caching and subsequently replaced
use of the module id when renaming promoted symbols (to avoid affects
due to link order changes). The sequentially assigned module id was not
removed, however, as it was still a convenience when serializing to/from
bitcode and assembly.
This patch removes the module id from this table, since it isn't
strictly needed and can lead to confusion on when it is appropriate to
use (e.g. see fix in D156525). It also takes a (likely not significant)
amount of overhead. Where an integer module id is needed (e.g. bitcode
writing), one is assigned on the fly.
There are a couple of test changes since the paths are now sorted
alphanumerically when assigning ids on the fly during assembly writing,
in order to ensure deterministic behavior.
Differential Revision: https://reviews.llvm.org/D156730
D153645 added additional X-Form load/stores that can be generated for TLS accesses.
However, these added instructions have not been accounted for in lld. As a result,
lld does not know how to handle them and cannot relax initial-exec to local-exec
when the initial-exec sequence contains these additional load/stores.
This patch aims to resolve https://github.com/llvm/llvm-project/issues/64424.
Differential Revision: https://reviews.llvm.org/D158197
D152495 makes clang warn on unused variables that are declared in conditions like `if (int var = init) {}`
This patch is an NFC fix to suppress the new warning in llvm,clang,lld builds to pass CI in the above patch.
Differential Revision: https://reviews.llvm.org/D158016
Many of these options can be passed to the linker by the Clang
driver based on other options passed to Clang, after
a23bf1786b. Before commit
5c92c9f34a, these were ignored by
lld, but now we're erroring out on the unrecognized options.
The ELF linker has even more LTO options available, but not
all of these are currently settable via the lld-link option
interface, and some aren't set automatically by Clang but only
if the user manually passes them - and thus probably aren't in
wide use so far. (Previously LLD/MinGW would have accepted them
silently but ignored them though.)
Differential Revision: https://reviews.llvm.org/D158887
LLD resolves symbols before performing LTO compilation, assuming that the symbols in question are resolved by the resulting object files from LTO. However, there is a scenario where the prevailing symbols might be resolved incorrectly due to specific assembly symbols not appearing in the symbol table of the bitcode. This patch deals with such a scenario by generating an error instead of silently allowing a mis-linkage.
If a prevailing symbol is resolved through post-loaded archives via LC linker options, a warning will now be issued.
Reviewed By: #lld-macho, thevinster
Differential Revision: https://reviews.llvm.org/D158003
This adds a new -Bsymbolic option that directly binds all non-weak
symbols. There's a couple of reasons motivating this:
* The new flag will match the default behavior on Mach-O, so you can get
consistent behavior across platforms.
* We have use cases for which making weak data preemptible is useful,
but we don't want to pessimize access to non-weak data. (For a large
internal app, we measured 2000+ data symbols whose accesses would be
unnecessarily pessimized by `-Bsymbolic-functions`.)
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D158322
This patch adds support to lld for --fat-lto-objects. We add a new
--fat-lto-objects option to LLD, and slightly change how it chooses input
files in the driver when the option is set.
Fat LTO objects contain both LTO compatible IR, as well as generated object
code. This allows users to defer the choice of whether to use LTO or not to
link-time. This is a feature available in GCC for some time, and makes the
existing -ffat-lto-objects option functional in the same way as GCC's.
If the --fat-lto-objects option is passed to LLD and the input files are fat
object files, then the linker will chose the LTO compatible bitcode sections
embedded within the fat object and link them together using LTO. Otherwise,
standard object file linking is done using the assembly section in the object
files.
The previous version of this patch had a missing `REQUIRES: x86` line in
`fatlto.invalid.s`. Additionally, it was reported that this patch caused
a test failure in `export-dynamic-symbols.s`, however,
29112a9946 disabled the
`export-dynamic-symbols.s` test on Windows due to a quotation difference
between platforms, unrelated to this patch.
Original RFC: https://discourse.llvm.org/t/rfc-ffat-lto-objects-support/63977
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D146778
This change writes the module name to the name section of the wasm
binary. We use the `-soname` argument to determine the name and we
default the output file basename if this option is not specified.
In the future we will likely want to embed the soname in the dylink
section too, but this the first step in supporting `-soname`.
Differential Revision: https://reviews.llvm.org/D158001
This reverts commit 4e3b89483a, with
fixes for places I'd missed updating in lld and lldb. I've also
renamed OptionVisibility::Default to "DefaultVis" to avoid ambiguity
since the undecorated name has to be available anywhere Options.inc is
included.
Original message follows:
This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and adds
variants of the OptTable APIs that use Visibility mask instead of
Include/Exclude flags.
We need to do this to clean up a bunch of complexity in the clang
driver's option handling - there's a whole slew of flags like
CoreOption, NoDriverOption, and FlangOnlyOption there today to try to
handle all of the permutations of flags that the various drivers need,
but it really doesn't scale well, as can be seen by things like the
somewhat recently introduced CLDXCOption.
Instead, we'll provide an additive model for visibility that's
separate from the other flags. For things like "HelpHidden", which is
used as a "subtractive" modifier for option visibility, we leave that
in "Flags" and handle it as a special case.
Note that we don't actually update the users of the Include/Exclude
APIs here or change the flags that exist in clang at all - that will
come in a follow up that refactors clang's Options.td to use the
increased flexibility this change allows.
Differential Revision: https://reviews.llvm.org/D157149
This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and adds
variants of the OptTable APIs that use Visibility mask instead of
Include/Exclude flags.
We need to do this to clean up a bunch of complexity in the clang
driver's option handling - there's a whole slew of flags like
CoreOption, NoDriverOption, and FlangOnlyOption there today to try to
handle all of the permutations of flags that the various drivers need,
but it really doesn't scale well, as can be seen by things like the
somewhat recently introduced CLDXCOption.
Instead, we'll provide an additive model for visibility that's
separate from the other flags. For things like "HelpHidden", which is
used as a "subtractive" modifier for option visibility, we leave that
in "Flags" and handle it as a special case.
Note that we don't actually update the users of the Include/Exclude
APIs here or change the flags that exist in clang at all - that will
come in a follow up that refactors clang's Options.td to use the
increased flexibility this change allows.
Differential Revision: https://reviews.llvm.org/D157149
LLD resolves symbols regardless of LTO modes early when reading and parsing input files in order. The object files built from LTO passes are appended later.
Because LLD eagerly resolves the LC linker options while parsing a new object file (and its chain of dependent libraries), the prior decision on pending prevailing symbols (belonging to some bitcode files) can change to ones in those native libraries that are just loaded.
This patch delays processing LC linker options until all the native object files are added after LTO is done, similar to LD64. This way we preserve the decision on prevailing symbols LLD made, regardless of LTO modes.
- When parsing a new object file in `parseLinkerOptions()`, it just parses LC linker options in the header, and saves those contents to `unprocessedLCLinkerOptions`.
- After LTO is finished, `resolveLCLinkerOptions()` is called to recursively load dependent libraries, starting with initial linker options collected in `unprocessedLCLinkerOptions` (which also updates during recursions)
Reviewed By: #lld-macho, int3
Differential Revision: https://reviews.llvm.org/D157716
When stub libraries trigger the fetching of new object files we can
potentially introduce new undefined symbols so process the stub in
loop until no new objects are pulled in.
Differential Revision: https://reviews.llvm.org/D153466
Details:
calling getMemoryBufferRef() on an empty archive can trigger segfault so the code should check before calling this.
this seems like a bug in the Archive API but that can be fixed separately.
P.S: follow up to D156468
Differential Revision: https://reviews.llvm.org/D157300
Update this diagnostic to mention the reason (unmatched '['), matching
the other diagnostic about stray '\'. The original pattern is omitted,
as some users may mention the original pattern in another position, not
repeating it.
`R_LARCH_PCREL20_S2` is a new added relocation type in LoongArch ELF
psABI v2.10 [1] which is not corvered by D138135 except `R_LARCH_64_PCREL`.
A motivation to support `R_LARCH_PCREL20_S2` in lld is to build the
runtime of .NET core (a.k.a `CoreCLR`) in which strict PC-relative
semantics need to be guaranteed [2]. The normal `pcalau12i + addi.d`
approach doesn't work because the code will be copied to other places
with different "page" and offsets. To achieve this, we can use `pcaddi`
with explicit `R_LARCH_PCREL20_S2` reloc to address +-2MB PC-relative
range with 4-bytes aligned.
[1]: https://github.com/loongson/la-abi-specs/releases/tag/v2.10
[2]: https://github.com/dotnet/runtime/blob/release/7.0/src/coreclr/vm/loongarch64/asmhelpers.S#L307
Reviewed By: xen0n, MaskRay
Differential Revision: https://reviews.llvm.org/D156772
