Commit Graph

14613 Commits

Author SHA1 Message Date
Fangrui Song 51ee08c217 [ELF] Enforce double-dash form for --ignore-{data,function}-pointer-equality --reproduce --thread
They are LLD-specific options. We have enforced double-dash forms for
other options (reduce collision with short options) but missed them.
2021-11-10 01:17:08 -08:00
Fangrui Song d71bb6a409 [ELF] Inline isPPC64SmallCodeModelTocReloc which is only called once. NFC 2021-11-09 20:41:05 -08:00
Fangrui Song bec28ee1ea [ELF] Move isStaticLinkTimeConstant closer to the only caller processRelocAux. NFC 2021-11-09 20:37:46 -08:00
Fangrui Song 213d1849a4 [ELF] Improve sh_info=0 and sh_info>=num_sections diagnostic for SHT_REL/SHT_RELA
PR52408 reported an sh_info=0 instance. I have seen sh_info=0
independently before.

sh_info>=num_sections is probably very rare. Just use one diagnostic for
the two types of errors.

Delete invalid-relocations.test which is covered by invalid/bad-reloc-target.test

Differential Revision: https://reviews.llvm.org/D113466
2021-11-09 09:54:12 -08:00
Vy Nguyen 2e1be96df6 Reland "[lld-macho] Fix assertion failure in registerCompactUnwind""
PR/52372

  Differential Revision: https://reviews.llvm.org/D112977

New changes:
- use llvm-otool instead of `otool` which doesn't in exist on non-OSX platforms
- add llvm-otool to the set of tools used by test so that the bot will use the <build_dir>/bin/llvm-otool instead of the unqualified `llvm-otool` (which may not exist)
- update tests since the latest (TOT) llvm-otool prints a space between two bytes and the old one doesn't.
2021-11-09 11:52:46 -05:00
Vy Nguyen eb4a517816 Revert "[lld-macho] Fix assertion failure in registerCompactUnwind"
broke windows build - reverting to investigate
This reverts commit b2d9258474.
2021-11-09 10:31:47 -05:00
Vy Nguyen b2d9258474 [lld-macho] Fix assertion failure in registerCompactUnwind
PR/52372

  Differential Revision: https://reviews.llvm.org/D112977
2021-11-09 10:08:17 -05:00
Fangrui Song 43bb5f0185 [docs] Remove outdated documentation for the legacy Atom-based LLD
The outdated documentation diverges a lot from the current state of
COFF/Mach-O/ELF/wasm ports and may just confuse users. It is better rewriting
some if useful.

Tested with `ninja docs-lld-html`

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

Differential Revision: https://reviews.llvm.org/D113432
2021-11-08 15:20:16 -08:00
Fangrui Song cebb0a64b4 [ELF][ARM] Improve error message for unknown relocation
Like rLLD354040.

Before: `error: unrecognized relocation Unknown (254)`
Now:    `error: unknown relocation (254) against symbol foo`
2021-11-08 12:39:08 -08:00
David Blaikie 78758026e2 Fix lld test after dwarfdump array syntax change 2021-11-05 23:00:29 -07:00
Fangrui Song 26a8ceba3e [llvm-readobj] Display DT_RELRSZ/DT_RELRENT as " (bytes)"
to match RELSZ/RELENT.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D113206
2021-11-05 10:02:49 -07:00
Quinn Pham c71fbdd87b [NFC] Inclusive language: Remove instances of master in URLs
[NFC] This patch fixes URLs containing "master". Old URLs were either broken or
redirecting to the new URL.

Reviewed By: #libc, ldionne, mehdi_amini

Differential Revision: https://reviews.llvm.org/D113186
2021-11-05 08:48:41 -05:00
Keith Smiley a7a2959901 [lld-macho] Replace LC_LINKER_OPTION parsing
This removes the tablegen based parsing of LC_LINKER_OPTION since it can
only actually contain a very small number of potential arguments. In our
project with tablegen this took 5 seconds before.

This replaces https://reviews.llvm.org/D113075

Differential Revision: https://reviews.llvm.org/D113235
2021-11-04 22:03:40 -07:00
Fangrui Song 005456e5fc [lld-macho] Fix an assertion failure when -u specifies an undefined section$start symbol
This matches ld64. Also improve the test for `-dead_strip`.

Reviewed By: #lld-macho, Jez Ng

Differential Revision: https://reviews.llvm.org/D113147
2021-11-04 21:28:33 -07:00
Keith Smiley 0bce3e3b84 [lld-macho] Clear resolvedReads cache
https://reviews.llvm.org/D113153#3108083

smeenai, int3

Differential Revision: https://reviews.llvm.org/D113198
2021-11-04 18:02:34 -07:00
Noah Shutty d788c44f5c [Support] Improve Caching conformance with Support library behavior
This diff makes several amendments to the local file caching mechanism
which was migrated from ThinLTO to Support in
rGe678c51177102845c93529d457b020f969125373 in response to follow-up
discussion on that commit.

Patch By: noajshu

Differential Revision: https://reviews.llvm.org/D113080
2021-11-04 13:00:44 -07:00
Keith Smiley e7fdff403e [lld-macho] Silently ignore the -objc_abi_version
This undocumented ld64 flag, based on the most recent ld64 source dump
from Xcode 12, only applies to i386. It seems like on all newer
architectures this behavior is the default.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D113070
2021-11-03 22:16:09 -07:00
Keith Smiley d49e7244cc [lld-macho] Cache readFile results
In one of our links lld was reading 760k files, but the unique number of
files was only 1500. This takes that link from 30 seconds to 8.

This seems like a heavy hammer, especially since some things don't need
to be cached, like the filelist arguments and the passed static
archives (the latter is already cached as a one off), but it seems ld64
does something similar here to short circuit these duplicate reads:

82e429e186/src/ld/InputFiles.cpp (L644-L665)

Of the types of files being read for our iOS app, the biggest problem
was constantly re-reading small tbd files:

```
% wc -l /tmp/read.txt
761414 /tmp/read.txt
% cat /tmp/read.txt | sort -u | wc -l
1503

% cat /tmp/read.txt | grep "\.a$" | wc -l
43721
% cat /tmp/read.txt | grep "\.tbd$" | wc -l
717656
```

We could likely hoist this logic up to not cache at this level, but it
would be a more invasive change to make sure all callers that needed it
cached the results.

I could see this being an issue with OOMs, and I'm not a linker expert so
maybe there's another way we should solve this problem? Feedback welcome!

Reviewed By: int3, #lld-macho

Differential Revision: https://reviews.llvm.org/D113153
2021-11-03 22:12:21 -07:00
Keith Smiley 6629ec3ecc [lld-macho] Implement -arch_errors_fatal
By default with ld64, architecture mismatches are just warnings, then
this flag can be passed to make these fail. This matches that behavior.

Reviewed By: int3, #lld-macho

Differential Revision: https://reviews.llvm.org/D113082
2021-11-03 22:01:53 -07:00
Jez Ng 4ae8c83104 [lld-macho][nfc] Remove unnecessary -pie flags in tests
D101513 means that we no longer need to specify `-pie` in most of our
test RUN commands. Let's clean up the unused flags so as not to confuse
future test writers.

Reviewed By: #lld-macho, oontvoo, MaskRay

Differential Revision: https://reviews.llvm.org/D113114
2021-11-04 00:02:03 -04:00
Keith Smiley 4313c56aa3 [lld-macho] Enable search-paths tests on macOS
I'm not sure what the history is here but this test passes on macOS
today. It seems like we should unify these tests if they need to run
cross platform.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D113085
2021-11-03 12:01:36 -07:00
Keith Smiley 63e65de3ff [lld-macho] Cache discovered framework paths
On our large iOS project this took a link from 1 minute 45 seconds to 45
seconds. For reference ld64 does the same link in ~20 seconds.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D113063
2021-11-03 11:11:54 -07:00
Keith Smiley f79e65e61f [lld-macho] Cache library paths from findLibrary
On top of https://reviews.llvm.org/D113063 this took another 10 seconds
off our overall link time.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D113073
2021-11-03 10:02:23 -07:00
Fangrui Song c977564fc2 Revert "[ELF] Try appeasing --target=armv7-linux-androideabi24 sanitizer symbolization tests"
This reverts commit 5cbec88cbf.

Vitaly said that 2faac77f26 actually works.

Sanitizer's armv7-linux-androideabi24 configuration has other issues which haven't been identified yet, but that's unrelated to the empty symbol name issue.
2021-11-03 00:56:09 -07:00
Fangrui Song 5cbec88cbf [ELF] Try appeasing --target=armv7-linux-androideabi24 sanitizer symbolization tests 2021-11-02 18:57:04 -07:00
Vy Nguyen 37f96cb478 Revert "[lld-macho] Change bitfield types to be identical."
This reverts commit ae31f9fbad.

Reason: bitfields can't be merged across parent/child classes anyway. So this change doesn't help.
2021-11-02 16:57:51 -04:00
Vy Nguyen ae31f9fbad [lld-macho] Change bitfield types to be identical.
Symbol's subclasses all have an additional bitfield of type uint8_t (RefState enum).
For the bitfields in the same block tomerge, they should be of the same type. (clang/gcc will work, but others like MSVC does not)

Differential Revision: https://reviews.llvm.org/D113040
2021-11-02 15:48:39 -04:00
Nico Weber 64c1734438 [lld/mac] Write -v output to stderr
This matches ld64, and it's conceivable that projects try to read
this information off stderr for that reason.

--version keeps writing to stdout.

Differential Revision: https://reviews.llvm.org/D113020
2021-11-02 13:59:14 -04:00
Vy Nguyen d7e5393af4 [lld-macho] Remove no_dtrace_dof from un-implemented group.
One fewer warning.
In practice, lld already "implements" it. (ie., it does not do dtrace-dof processing ever).

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D112934
2021-11-02 12:36:08 -04:00
Vy Nguyen 3f35dd06a5 [lld-macho][nfc][cleanup] Fix a few code style lints and clang-tidy findings
- Use .empty() instead of `size() == 0` when possible.
- Use const-ref to avoid copying

Differential Revision: https://reviews.llvm.org/D112978
2021-11-02 11:26:15 -04:00
Shoaib Meenai 7a4b27609d [lld] Add test suite mode for running LLD main twice
LLD_IN_TEST determines how many times each port's `main` function is
run in each LLD process, and setting LLD_IN_TEST=2 (or higher) is useful
for checking if we're cleaning up and resetting global state correctly.
Add a test suite parameter to enable this easily. There's work in
progress to remove global state (e.g. D108850), but this seems useful in
the interim.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D112898
2021-11-01 14:26:54 -07:00
Fangrui Song 2f7366c89d [ELF] Simplify R_DTPREL. NFC 2021-10-31 20:30:00 -07:00
Shoaib Meenai 264d3b6d4e [MachO] Use error instead of fatal for missing -arch
`fatal` should only be used for malformed inputs according to
ErrorHandler.h; `error` is more appropriate for missing arguments,
accompanied by a check to bail out early in case of the error. Some
tests need to be adjusted accordingly.

Makes `lld/test/MachO/arch.s` pass with `LLD_IN_TEST=2`.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D112879
2021-10-31 16:31:21 -07:00
Shoaib Meenai 0f6d720f1f [MachO] Properly reset global state
We need to reset global state between runs, similar to the other ports.
There's some file-static state which needs to be reset as well and we
need to add some new helpers for that.

With this change, most LLD Mach-O tests pass with `LLD_IN_TEST=2` (which
runs the linker twice on each test). Some tests will be fixed by the
remainder of this stack, and the rest are fundamentally incompatible
with that mode (e.g. they intentionally throw fatal errors).

Fixes PR52070.

Reviewed By: #lld-macho, int3

Differential Revision: https://reviews.llvm.org/D112878
2021-10-31 16:14:29 -07:00
Nico Weber f964ca896f [lld/coff] Add parsing for /pdbpagesize: flag
It's not used for anything yet, but we now accept `/pdbpagesize:4096`
(the default behavior) and we give arguably more useful diagnostics
for other values.

It's plumbed through to the MSF layer, so just uncommenting out
the bit in DriverUtils.cpp that rejects args other than 4096 is enough
to try other values.

Differential Revision: https://reviews.llvm.org/D112871
2021-10-31 18:36:23 -04:00
Fangrui Song 9f8ffaaa0b [ELF] Replace "symbol '...' has no type" diagnostic with "relocation ... cannot be used against symbol '...'"
The "symbol 'foo' has no type" diagnostic tries to inform that copy
relocation/canonical PLT entry cannot be used, but the diagnostic is often
incorrect and confusing.
2021-10-31 13:12:26 -07:00
Fangrui Song 164194a5af [ELF] Untangle R_GOT style TLS IE and processRelocAux. NFC 2021-10-31 12:38:36 -07:00
Fangrui Song 55e69ece72 [ELF] Remove -Wl,-z,notext hint
The hint does not pull its weight:

* adding -Wl,-z,notext often won't work (relocation types other than `symbolRel`, e.g. `R_AARCH64_LDST32_ABS_LO12_NC`)
* for pure (no assembly) C/C++ projects, the "-fPIC" hint is sufficient
2021-10-31 12:10:43 -07:00
Fangrui Song b76aacef5f [ELF] Simplify isStaticLinkTimeConstant. NFC 2021-10-31 10:46:42 -07:00
Fangrui Song 3fe4b54915 [ELF] Make getImplicitAddend return 0 for R_ARM_V4BX. NFC
Will be useful if we move R_ARM_V4BX handling around.
2021-10-30 23:31:39 -07:00
Fangrui Song aa1d32f519 [ELF][Mips] Use R_DTPREL for R_MIPS_TLS_DTPREL* 2021-10-30 21:58:43 -07:00
Nico Weber 2d48b19136 [lld/mac] Fix mislink with ICF
When comparing relocations against two symbols, ICF's equalsConstant() did not
look at the value of the two symbols. With subsections_via_symbols, the value
is usually 0 but not always: In particular, it isn't 0 for constants in string
and literal sections. Since we ignored the value, comparing two constant string
symbols or two literal symbols always compared the 0th's element, so functions
in the same TU always compared as equal.

This can cause mislinks, and, with -dead_strip, crashes.

Fixes PR52349, see that bug for lots of details and examples of mislinks.

While here, make the existing assembly in icf-literals.s a bit more realistic
(use leaq instead of movq with strings, and use foo(%rip) instead of
foo@gotpcrel(%rip)). This has no interesting effect, it just maybe makes the
test look a bit less surprising.

Differential Revision: https://reviews.llvm.org/D112862
2021-10-30 18:58:59 -04:00
Sam Clegg 182b72aa48 [lld][WebAssembly] Generate TLS relocation code also when linking statically
Previously relocations were only generated for PIC output, but
relocations for TLS GOT entries are always needed when shared
memory is enabled, not just in PIC mode.

This means that the `__wasm_apply_global_tls_relocs` is now
generated even for statically linked (non-PIC) output.  Without
this the globals that hold the addresses of TLS symbols are
not set correctly.

Differential Revision: https://reviews.llvm.org/D112833
2021-10-29 13:26:35 -07:00
Sam Clegg fad05465c1 [lld][WebAssembly] Handle TLS variables in Symbol::getVA. NFC
In the shared memory case we can always assume that TLS addresses
are relative to __tls_base.  In the non-shared memory case TLS
variables are absolute, just like normal data addresses.

This simplifies the code in calcNewValue so that TLS relocations
no longer need special handling.

Differential Revision: https://reviews.llvm.org/D112831
2021-10-29 10:45:30 -07:00
Jez Ng 6c2f26a159 [lld-macho] -all_load and -ObjC should not affect LC_LINKER_OPTION flags
In particular, they should not cause archives to be eagerly loaded. This
matches ld64's behavior.

Fixes PR52246.

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D112756
2021-10-29 11:00:28 -04:00
Jez Ng a271f2410f [lld-macho][nfc] Canonicalize all pointers to InputSections early on
Having to remember to call `canonical()` all over the place is
error-prone; let's do it in a centralized location instead. It also
appears to improve performance slightly.

             base           diff           difference (95% CI)
  sys_time   0.984 ± 0.009  0.983 ± 0.014  [  -0.8% ..   +0.6%]
  user_time  6.508 ± 0.035  6.475 ± 0.036  [  -0.8% ..   -0.2%]
  wall_time  5.321 ± 0.034  5.300 ± 0.033  [  -0.7% ..   -0.1%]
  samples    36             23

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D112687
2021-10-29 11:00:28 -04:00
Fangrui Song 3a4b605bc1 [lld-macho] Internalize createFiles. NFC 2021-10-28 22:14:37 -07:00
Fangrui Song 6fcc19afb9 [ELF] Simplify R_TPREL formula after D111365 2021-10-28 21:03:53 -07:00
Fangrui Song 6e04ec801b [docs] Fix docs-lld-html 2021-10-28 18:44:44 -07:00
Fangrui Song e39c138f45 [ELF] Implement TLSDESC for x86-32
`-z rela` is also supported.

Tested with:

```
cat > ./a.c <<eof
#include <assert.h>
int foo();
int bar();
int main() {
  assert(foo() == 2);
  assert(foo() == 4);
  assert(bar() == 2);
  assert(bar() == 4);
}
eof

cat > ./b.c <<eof
#include <stdio.h>
__thread int tls0;
extern __thread int tls1;
int foo() { return ++tls0 + ++tls1; }
static __thread int tls2, tls3;
int bar() { return ++tls2 + ++tls3; }
eof

echo '__thread int tls1;' > ./c.c

sed 's/        /\t/' > ./Makefile <<'eof'
.MAKE.MODE = meta curDirOk=true

CC := gcc -m32 -g -fpic -mtls-dialect=gnu2
LDFLAGS := -m32 -Wl,-rpath=.

all: a0 a1 a2

run: all
        ./a0 && ./a1 && ./a2

c.so: c.o; ${LINK.c} -shared $> -o $@
bc.so: b.o c.o; ${LINK.c} -shared $> -o $@
b.so: b.o c.so; ${LINK.c} -shared $> -o $@

a0: a.o b.o c.o; ${LINK.c} $> -o $@
a1: a.o b.so; ${LINK.c} $> -o $@
a2: a.o bc.so; ${LINK.c} $> -o $@
eof
```
and glibc `elf/tst-gnu2-tls1`.

`/usr/local/bin/ld` points to the freshly built `lld`.

`bmake run && bmake CFLAGS=-O1 run` => ok.

Differential Revision: https://reviews.llvm.org/D112582
2021-10-28 17:52:03 -07:00