Commit Graph

7241 Commits

Author SHA1 Message Date
Keith Smiley 67090e3446 [lld-macho] Implement -noall_load
This flag is the default, so in ld64 it is not implemented, but it can
be useful to negate previous -all_load arguments. Specifically if your
build system has some global linker flags, that you may want to negate
for specific links. We use something like this today to make sure some
C++ symbols are automatically discovered for all links, which passing
-all_load hides.

Differential Revision: https://reviews.llvm.org/D117629
2022-01-19 13:12:18 -08:00
Fangrui Song 5bd38a2826 [ELF] Fix split-stack caller with hidden non-split-stack callee
Fix a regression after aabe901d57 (`[ELF] Remove
one redundant computeBinding`): isLocal() does not indicate that the symbol is
originally local. For simplicity, just drop this optimization.
2022-01-19 12:25:01 -08:00
Fangrui Song 0aae2bf373 [lld-macho] Add --start-lib --end-lib
In ld.lld, when an ObjFile/BitcodeFile is read in --start-lib state, the file is
given archive semantics. --end-lib closes the previous --start-lib. A build
system can use this feature as an alternative to archives. This patch ports
the feature to lld-macho.

--start-lib and --end-lib are positional, unlike usual ld64 options.
I think the slight drawback does not matter as (a) reusing option names
make build systems convenient (b) `--start-lib a.o b.o --end-lib` conveys more
information than an alternative design: `-objlib a.o -objlib b.o` because
--start-lib makes it clear which objects are in the same conceptual archive.
This provides flexibility (c) `-objlib`/`-filelist` interaction may be weird.

Close https://github.com/llvm/llvm-project/issues/52931

Reviewed By: #lld-macho, Jez Ng, oontvoo

Differential Revision: https://reviews.llvm.org/D116913
2022-01-19 10:14:49 -08:00
Fangrui Song d838bf2adc [ELF] Allow non-bitcode archive with an empty index
When an archive with an empty index contains only bitcode files, it is
handled as a group of lazy (--start-lib) object files. If there is a
non-bitcode file, there will be a diagnostic a la GNU ld.

For some programs, the archive member extraction ratio is high (e.g. for chrome,
79% archive members are extracted according to --print-archive-stats=). Because
symbol interning is cached for ObjFile::parseLazy but not for ArchiveFile,
parsing an archive as a group of --start-lib object files may be faster.

If the linker speculatively creates section representations for archive members,
the archive index will not be used.

If we take the above view, the archive index is essentially useless. If a user
wants a fast build without using --start-lib, they may just build thin archives
without index (`ar rcS --thin`).

Therefore, I suggest that we no longer treat the code as a hack, instead as a
supported feature. I believe we will do this anyway if we add parallel symbol
interning (parallel symbol interning for lazy object files is simpler than that
for archives).

Ecosystem issues:

* parseLazy actually has nearly the same behavior as ArchiveFile::parse, but the symbol order may be different.
* users may get addicted to the behavior and build archives not working with GNU ld and gold. I think it is easy to rebuild archives to be compatible.

Reviewed By: ikudrin

Differential Revision: https://reviews.llvm.org/D117284
2022-01-19 10:01:53 -08:00
Ayke van Laethem d649faff9c
[LLD][COFF] Support GNU style == aliases
D46245 added support for this in llvm-libtool, but while lld-link can
also create .lib files from .def files it didn't support aliases.

I compared the Inputs/library.def test against the output from
llvm-libtool and it matches, except for the fact that lld-link reorders
functions for some reason.

I have also verified that this fixes a bug I was running into while
trying to compile .def files to .lib files in MinGW-w64 (using lld-link
instead of llvm-libtool).

Differential Revision: https://reviews.llvm.org/D113365
2022-01-19 14:22:13 +01:00
Fangrui Song 288082d45d [ELF] Move SHT_REL/SHT_RELA handling from createInputSection to initializeSections
This simplifies the code a bit. While here,

* change the `multiple relocation sections` diagnostic from `fatal` to `error` and include the relocated section name.
* drop less useful name from `getRelocTarget`. Without -r/--emit-relocs we don't need to get SHT_REL/SHT_RELA names.
2022-01-18 23:31:51 -08:00
Vincent Lee e5347f2556 [lld-macho] Allow deduplicate-literals to be overridden
It's still uncertain but whether we want to have `deduplicate-literals` be the
default flag for LLD out of the box or not. If `deduplicate-literals` is the default
behavior, then we will need a way override it and not deduplicate. Luckily, we
have `no_deduplicate` to fill this gap. For now, I've set the default to be false
which aligns with the existing behavior. That can only always be changed after
discussions on D117250.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D117387
2022-01-18 15:42:59 -08:00
Sam Clegg ec47dba1c8 [lld][WebAssembly] Perform data relocations during start function
We already perform memory initialization and apply global relocations
during start.  It makes sense to performs data relocations too.  I think
the reason we were not doing this already is solely historical.

Differential Revision: https://reviews.llvm.org/D117412
2022-01-18 14:08:42 -08:00
Sam Clegg ae1573e131 [lld][WebAssembly] Reinstate mistakenly disabled test. NFC
It seems the first half of this test was disabled in error
as part of https://reviews.llvm.org/D93066.

Differential Revision: https://reviews.llvm.org/D117594
2022-01-18 12:22:22 -08:00
Fangrui Song d46054d75d [ELF][test] Add --build-id tests for -z separate-loadable-segments and --no-rosegment 2022-01-16 22:36:22 -08:00
Fangrui Song 3736d0854a [ELF] Optimize -z combreloc
Sorting dynamic relocations is a bottleneck. Simplifying the comparator improves
performance. Linking clang is 4~5% faster with --threads=8.

This change may shuffle R_MIPS_REL32 for Mips and is a NFC for non-Mips.
2022-01-15 22:33:51 -08:00
Fangrui Song 8b2f33231c [ELF] Make some diagnostics follow the convention 2022-01-15 10:46:25 -08:00
Phoebe Wang 0f499d1ed4 Revert "[X86][LLD] Update datelayout in LLD tests. NFCI"
This reverts commit 9b43237128.
2022-01-15 10:54:37 +08:00
Igor Kudrin e00ac48df3 [ELF] Use tombstone values for discarded symbols in relocatable output
This extends D81784. Sections can be discarded when linking a
relocatable output. Before the patch, LLD did not update the content
of debug sections and only replaced the corresponding relocations with
R_*_NONE, which could break the debug information.

Differential Revision: https://reviews.llvm.org/D116946
2022-01-13 11:38:26 +07:00
Fangrui Song b592cbf329 [ELF][test] Improve discard-gnu-hash.s to check DT_HASH and DT_GNU_HASH 2022-01-12 12:43:49 -08:00
Fangrui Song bf9c8636f2 [ELF] Support discarding .relr.dyn
db08df0570 does not work because part.relrDyn is
a unique_ptr and `reset` destroys the object which may still be referenced.

This commit uses the D114180 approach. Also improve the test to check that there
is no R_X86_64_RELATIVE.
2022-01-12 11:55:22 -08:00
Fangrui Song d8b7ae947d [ELF][test] Temporarily remove .relr.dyn test which is not working 2022-01-12 11:43:56 -08:00
Fangrui Song f8476fd47b [llvm-ar][test] Test that --plugin is ignored 2022-01-12 11:32:31 -08:00
Fangrui Song 5014d6fc53 [ELF] -Map --why-extract=: print despite errors
Fix https://github.com/llvm/llvm-project/issues/53073

In case of a relocation error, GNU ld's link map includes
the archive member extraction information but not output sections.

Our -Map and --why-extract= are currently no-op in case of an error.
This change makes the two options work.

Reviewed By: ikudrin, peter.smith

Differential Revision: https://reviews.llvm.org/D116838
2022-01-12 10:40:33 -08:00
Fangrui Song db08df0570 [ELF] Support discarding .relr.dyn
to prepare for D116838, otherwise for linkerscript/discard-section-err.s,
there will be a null pointer dereference in `part.relrDyn->getParent()->size`
in `finalizeSynthetic(part.relrDyn.get())`.
2022-01-12 10:38:59 -08:00
Leonard Grey 6db04b97e6 [lld-macho] Port CallGraphSort from COFF/ELF
Depends on D112160

This adds the new options `--call-graph-profile-sort` (default),
`--no-call-graph-profile-sort` and `--print-symbol-order=`. If call graph
profile sorting is enabled, reads `__LLVM,__cg_profile` sections from object
files and uses the resulting graph to put callees and callers close to each
other in the final binary via the C3 clustering heuristic.

Differential Revision: https://reviews.llvm.org/D112164
2022-01-12 10:47:04 -05:00
Phoebe Wang 9b43237128 [X86][LLD] Update datelayout in LLD tests. NFCI
rG1bb0caf56168 changed the datalayout of f80 on Windows 32 bits. But it
missed the related use in the LLD tests. This patch will fix the
problem catched by buildbot.
2022-01-12 19:13:41 +08:00
Jez Ng 62790f366f [lld-macho] Try and fix map-file.s' flakiness
After {D117069}, map-file.s seems flaky. It seems that the "Total Write
map file" section always exists, but the "Write map file" sub-section
may or may not be emitted. So we check for the former.
2022-01-11 23:02:45 -08:00
Jez Ng e976c457c5 [lld-macho] Initialize separate time trace profiler for mapfile worker
After {D115416}, the "Write map file" event no longer shows up
in the time trace. Each time trace profiler instance is thread-local,
but we had neglected to initialize a separate instance for the mapfile
worker thread.

Reviewed By: keith

Differential Revision: https://reviews.llvm.org/D117069
2022-01-11 17:45:18 -08:00
Simon Atanasyan 0199e47373 [mips][lld] Add test case to check symbol index reading on mips64el. NFC 2022-01-11 19:08:20 +03:00
Fangrui Song 2968467e39 [lld-macho][test] Add missing coverage for archive/dylib resolution after D115092
When `file->fetch(sym)` is replaced with a no-op, no test fails.

The new test catches the case.

Reviewed By: #lld-macho, oontvoo

Differential Revision: https://reviews.llvm.org/D116916
2022-01-10 19:36:24 -08:00
Fangrui Song 7f1955dc96 [ELF] Support mixed TLSDESC and TLS GD
We only support both TLSDESC and TLS GD for x86 so this is an x86-specific
problem. If both are used, only one R_X86_64_TLSDESC is produced and TLS GD
accesses will incorrectly reference R_X86_64_TLSDESC. Fix this by introducing
SymbolAux::tlsDescIdx.

Reviewed By: ikudrin

Differential Revision: https://reviews.llvm.org/D116900
2022-01-10 10:03:21 -08:00
Alexander Shaposhnikov 8acc3b4ab0 [lld][ELF] Support adrp+ldr GOT optimization for AArch64
This diff adds first bits to support relocation relaxations for AArch64
discussed on https://github.com/ARM-software/abi-aa/pull/106.
In particular, the case of

adrp x0, :got: symbol
ldr x0, [x0, :got_lo12: symbol]

is handled.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D112063
2022-01-10 05:20:37 +00:00
Brian Cain ddf1fb1f13 [Hexagon] Save results from partial compound
Previously compounding was all-or-nothing.  Now, the
compounding attempts will iterate and yield the most
compounds that still result in a valid packet.
2022-01-06 14:08:33 -08:00
Vy Nguyen fb9bfb2c59 [lld][macho][nfc] Make tests less britle by not expecting ordering in symbol table dump.
(parial)fixes PR/53026

Differential Revision: https://reviews.llvm.org/D116718
2022-01-06 09:45:44 -05:00
Fangrui Song 6e4bbbfcc8 [ELF] Enforce double-dash form for --color-diagnostics/--rsp-quoting/--symbol-ordering-file
They are LLD-specific and by convention we enforce the double-dash form to avoid
collision with short options (e.g. weird `-c olor-diagnostics` interpretation in
GNU ld). They are rarely used and to the best of my investigation the undesired
single-dash forms are not used in the wild.
2022-01-06 01:02:14 -08:00
Fangrui Song bfc2f4b122 [ELF] Update help messages to prefer canonical name for some long options
And improve the help message for --pop-state.
2022-01-06 00:43:46 -08:00
Nico Weber d5b2921faf [lld/tests] Stop setting the "asserts" and "debug" features
The last use of `REQUIRES: debug` was removed in 2013 in 72c5d3d7c in favor of
`REQUIRES: asserts`.

The last use of `REQUIRES: asserts` was removed in 2015 in 251b0e268 when the
old COFF linker was removed.

lld's test suite currently has no behavior difference with respect to
assertions or debug builds (and hasn't had it for 6 years). Let's keep it that
way :)

Differential Revision: https://reviews.llvm.org/D115941
2022-01-05 13:39:17 -05:00
Nico Weber 085f078307 Revert "Revert D109159 "[amdgpu] Enable selection of `s_cselect_b64`.""
This reverts commit 859ebca744.
The change contained many unrelated changes and e.g. restored
unit test failes for the old lld port.
2022-01-05 13:10:25 -05:00
David Salinas 859ebca744 Revert D109159 "[amdgpu] Enable selection of `s_cselect_b64`."
This reverts commit 640beb38e7.

That commit caused performance degradtion in Quicksilver test QS:sGPU and a functional test failure in (rocPRIM rocprim.device_segmented_radix_sort).
Reverting until we have a better solution to s_cselect_b64 codegen cleanup

Change-Id: Ibf8e397df94001f248fba609f072088a46abae08

Reviewed By: kzhuravl

Differential Revision: https://reviews.llvm.org/D115960

Change-Id: Id169459ce4dfffa857d5645a0af50b0063ce1105
2022-01-05 17:57:32 +00:00
Fangrui Song 00dd2d15a4 [ELF] --symbol-ordering-file: remove weird !lazy condition for "no such symbol" diagnostic
The diagnostic is emitted for an unextracted lazy symbol but suppressed for an
undefined symbol. Suppressing the diagnostic for unextracted lazy symbol
probably makes more sense because (a) an unextracted lazy symbol is quite
similar to an undefined symbol and (b) an unextracted lazy symbol is different
from "no such symbol".
2022-01-05 02:04:36 -08:00
Xu Mingjie b5149f4e66 [LTO] Fix assertion failed when flushing bitcode incrementally for LTO output.
In https://reviews.llvm.org/D86905, we introduce an optimization, when lld emits LLVM bitcode,
we allow bitcode writer flush data to disk early when buffered data size is above some threshold.

But when `--plugin-opt=emit-llvm` and `-o /dev/null` are used,
lld will trigger assertion `BytesRead >= 0 && static_cast<size_t>(BytesRead) == BytesFromDisk`.
When we write output to /dev/null, BytesRead is zero, but at this program point BytesFromDisk is always non-zero.

Reviewed By: stephan.yichao.zhao, MaskRay

Differential Revision: https://reviews.llvm.org/D112297
2022-01-04 21:40:23 -08:00
Luís Ferreira 10e40a4ea3 [lld] Add support for other demanglers other than Itanium
LLVM core library supports demangling other mangled symbols other than itanium,
such as D and Rust. LLD should use those demanglers in order to output pretty
demangled symbols on error messages.

Reviewed By: MaskRay, #lld-macho

Differential Revision: https://reviews.llvm.org/D116279
2022-01-05 03:25:41 +00:00
Luís Ferreira 8792cd75d0 Revert "[lld] Add support for other demanglers other than Itanium"
This reverts commit e60d6dfd5a.

clang-ppc64le-rhel buildbot failed (https://lab.llvm.org/buildbot#builders/57/builds/13424):

    tools/lld/MachO/CMakeFiles/lldMachO.dir/Symbols.cpp.o: In function `lld::demangle(llvm::StringRef, bool)':
    Symbols.cpp:(.text._ZN3lld8demangleEN4llvm9StringRefEb[_ZN3lld8demangleEN4llvm9StringRefEb]+0x90): undefined reference to `llvm::demangle(std::string const&)'
2021-12-30 18:04:21 +00:00
Luís Ferreira e60d6dfd5a [lld] Add support for other demanglers other than Itanium
LLVM core library supports demangling other mangled symbols other than itanium,
such as D and Rust. LLD should use those demanglers in order to output pretty
demangled symbols on error messages.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D116279
2021-12-30 17:52:38 +00:00
Fangrui Song de92a13fec [ELF] --gc-sections: Work around SHT_PROGBITS .init_array.N for Rust
See https://github.com/rust-lang/rust/issues/92181
2021-12-28 16:40:51 -08:00
Mike Hommey 319181f767 [lld-macho] Fix alignment of TLV data sections
References from thread-local variable sections are treated as offsets
relative to the start of the thread-local data memory area, which is
initialized via copying all the TLV data sections (which are all
contiguous). If later data sections require a greater alignment than
earlier ones, the offsets of data within those sections won't be
guaranteed to aligned unless we normalize alignments. We therefore use
the largest alignment for all TLV data sections.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D116263
2021-12-28 19:03:13 -05:00
Fangrui Song 7924b3814f [ELF] Add Symbol::hasVersionSuffix
"Process symbol versions" may take 2+% time.
"Redirect symbols" may take 0.6% time.
This change speeds up the two passes and makes `*sym.getVersionSuffix()
== '@'` in the `undefined reference` diagnostic cleaner.

Linking chrome (no debug info) and another large program is 1.5% faster.

For empty-ver2.s: the behavior now matches GNU ld, though I'd consider the input
invalid and the exact behavior does not matter.
2021-12-26 17:25:54 -08:00
Fangrui Song 20b4704da3 [ELF] reportRangeError: mention symbol name for non-STT_SECTION local symbols like non-global symbols 2021-12-25 23:46:47 -08:00
Fangrui Song d5e310b154 [ELF][test] Make some TLS tests less sensitive to addresses 2021-12-25 22:05:20 -08:00
Fangrui Song 70912420bb [ELF] Move TLS dynamic relocations to postScanRelocations
This temporarily increases sizeof(SymbolUnion), but allows us to mov GOT/PLT/etc
index members outside Symbol in the future.

Then, we can make TLSDESC and TLSGD use different indexes and support mixed
TLSDESC and TLSGD (tested by x86-64-tlsdesc-gd-mixed.s).

Note: needsTlsGd and needsTlsGdToIe may optionally be combined.

Test updates are due to reordered GOT entries.
2021-12-24 22:36:49 -08:00
Fangrui Song cde37a7e5a [ELF][test] Add tests for mixed GD-to-IE and IE, mixed TLSDESC and GD
Note: mixed TLSDESC and GD currently does not work.
2021-12-24 22:24:15 -08:00
Kristina Bessonova 81378f7e56 Revert "[DwarfDebug] Support emitting function-local declaration for a lexical block" & dependent patches
Try to revert D113741 once again.

This also reverts 0ac75e82ff (D114705)
as it causes LLDB's lldb-api.lang/cpp/nsimport.TestCppNsImport.py test
failure w/o D113741.

This reverts commit f9607d45f3.

Differential Revision: https://reviews.llvm.org/D116225
2021-12-24 00:47:04 +02:00
Fangrui Song bf45624ba0 [ELF][PPC32] Support .got2 in an output section description
I added `PPC32Got2Section` D62464 to support .got2 but did not implement .got2
in another output section.

PR52799 has a linker script placing .got2 in .rodata, which causes a null
pointer dereference because a MergeSyntheticSection's file is nullptr.
Add the support.
2021-12-23 11:32:44 -08:00
Fangrui Song 3a5fb57393 [ELF] Replace LazyObjFile with lazy ObjFile/BitcodeFile
The new `lazy` state is the inverse of the previous `LazyObjFile::extracted`.
There are many advantages:

* previously when a LazyObjFile was extracted, a new ObjFile/BitcodeFile was created; now the file is reused, just with `lazy` cleared
* avoid the confusing transfer of `symbols` from LazyObjFile to the new file
* the `incompatible file:` diagnostic is unified with `is incompatible with`
* simpler code, smaller executable (6200+ bytes smaller on x86-64)
* make eager parsing feasible (for parallel section/symbol table initialization)
2021-12-22 17:41:50 -08:00