7246 Commits

Author SHA1 Message Date
Fangrui Song
c03fdd3403 [ELF] Fix the branch range computation when reusing a thunk
Notation: dst is `t->getThunkTargetSym()->getVA()`

On AArch64, when `src-0x8000000-r_addend <= dst < src-0x8000000`, the condition
`target->inBranchRange(rel.type, src, rel.sym->getVA(rel.addend))` may
incorrectly consider a thunk reusable.
`rel.addend = -getPCBias(rel.type)` resets the addend to 0 for AArch64/PPC
and the zero addend is used by `rel.sym->getVA(rel.addend)` to check
out-of-range relocations.

See the test for a case this computation is wrong:
`error: a.o:(.text_high+0x4): relocation R_AARCH64_JUMP26 out of range: -134217732 is not in [-134217728, 134217727]`
I have seen a real world case with r_addend=19960.

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D117734
2022-01-24 09:03:21 -08:00
Peter Smith
a08447d0de [LLD][ELF][AArch64] Update test with incorrect REQUIRES line [NFC]
D54759 introduced aarch64-combined-dynrel.s and
aarch64-combined-dynrel-ifunc.s . Unfortunately the requires line
at the top was AArch64 instead of aarch64 which means they were never
run. Update the tests to use aarch64 and fix to match current lld output.

Differential Revision: https://reviews.llvm.org/D117896
2022-01-24 10:04:28 +00:00
Roger Kim
f84023a812 [lld][macho] Stop grouping symbols by sections in mapfile.
As per [Bug 50689](https://bugs.llvm.org/show_bug.cgi?id=50689),

```
2. getSectionSyms() puts all the symbols into a map of section -> symbols, but this seems unnecessary. This was likely copied from the ELF port, which prints a section header before the list of symbols it contains. But the Mach-O map file doesn't print these headers.
```

This diff removes `getSectionSyms()` and keeps all symbols in a flat vector.

What does ld64's mapfile look like?
```
$ llvm-mc -filetype=obj -triple=x86_64-apple-darwin test.s -o test.o
$ llvm-mc -filetype=obj -triple=x86_64-apple-darwin foo.s -o foo.o
$ ld -map map test.o foo.o -o out -L/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib -lSystem
```

```
[  0] linker synthesized
[  1] test.o
[  2] foo.o
0x100003FB7     0x00000001      __TEXT  __text
0x100003FB8     0x00000000      __TEXT  obj
0x100003FB8     0x00000048      __TEXT  __unwind_info
0x100004000     0x00000001      __DATA  __common
0x100003FB7     0x00000001      [  1] _main
0x100003FB8     0x00000000      [  2] _foo
0x100003FB8     0x00000048      [  0] compact unwind info
0x100004000     0x00000001      [  1] _number
```

Perf numbers when linking chromium framework on a 16-Core Intel Xeon W Mac Pro:
```
base           diff           difference (95% CI)
sys_time   1.406 ± 0.020  1.388 ± 0.019  [  -1.9% ..   -0.6%]
user_time  5.557 ± 0.023  5.914 ± 0.020  [  +6.2% ..   +6.6%]
wall_time  4.455 ± 0.041  4.436 ± 0.035  [  -0.8% ..   -0.0%]
samples    35             35
```

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D114735
2022-01-20 12:16:37 -08:00
Sam Clegg
feddf11502 [lld][WebAssemlby] Convert test to check disassembly output. NFC
Differential Revision: https://reviews.llvm.org/D117739
2022-01-20 09:32:01 -08:00
Alexandre Ganea
aba5b91b69 Re-land [CodeView] Add full repro to LF_BUILDINFO record
This patch writes the full -cc1 command into the resulting .OBJ, like MSVC does. This allows for external tools (Recode, Live++) to rebuild a source file without any external dependency but the .OBJ itself (other than the compiler) and without knowledge of the build system.

The LF_BUILDINFO record stores a full path to the compiler, the PWD (CWD at program startup), a relative or absolute path to the source, and the full CC1 command line. The stored command line is self-standing (does not depend on the environment). In the same way, MSVC doesn't exactly store the provided command-line, but an expanded version (a somehow equivalent of CC1) which is also self-standing.

For more information see PR36198 and D43002.

Differential Revision: https://reviews.llvm.org/D80833
2022-01-19 19:44:37 -05:00
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 aabe901d57d6df4cd2786163359a7b2a7aae8c32 (`[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 9b43237128da0a7a3bc8a16f6f2c0897b9e842be.
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
db08df0570b6dfaf00d7b1b8555c1d2d4effb224 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 859ebca744e634dcc89a2294ffa41574f947bd62.
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 640beb38e7710b939b3cfb3f4c54accc694b1d30.

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 e60d6dfd5acdc821d391ad5af2c706397bdfd36a.

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