Commit Graph

13755 Commits

Author SHA1 Message Date
Sam Clegg
34d033ca12 [lld][WebAssembly] Allow --export of optional start/stop symbols
This moves the error checking until after all optional
symbols (including the section start/end symbols) have
been created.

Differential Revision: https://reviews.llvm.org/D96318
2021-02-09 13:14:52 -08:00
Nico Weber
e0b8604e5d [lld/mac] Implement -u flag
Since we emit diagnostics for undefineds in Writer::scanRelocations()
and symbols referenced by -u flags aren't referenced by any relocations,
this needs some manual code (similar to the entry point).

Differential Revision: https://reviews.llvm.org/D94371
2021-02-09 08:23:06 -05:00
Fangrui Song
d82679d805 [ELF] Drop Android specific workaround -m aarch64_elf64_le_vec
`extern const bfd_target aarch64_elf64_le_vec;` is a variable in BFD.
It was somehow misused as an emulation by Android.

```
% aarch64-linux-gnu-ld -m aarch64_elf64_le_vec a.o
aarch64-linux-gnu-ld: unrecognised emulation mode: aarch64_elf64_le_vec
Supported emulations: aarch64linux aarch64elf aarch64elf32 aarch64elf32b aarch64elfb armelf armelfb aarch64linuxb aarch64linux32 aarch64linux32b armelfb_linux_eabi armelf_linux_eabi
```

Acked by Stephen Hines, who removed the flag from Android a while back.
2021-02-09 00:43:10 -08:00
Hongtao Yu
5b8db127a3 [ELF] Rewriting the path of sample profile file for --reproduce response.txt
Rewritting the path of the sample profile file in response.txt to be relative to the repro tar.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D96193
2021-02-09 00:00:16 -08:00
Sam Clegg
88e4056b44 [lld][WebAssembly] Fix typo in function name
addOptionalGlobalSymbols should be addOptionalGlobalSymbol.

Also, remove unnecessary additional argument to make the signature match
the sibling function: addOptionalDataSymbol.

Differential Revision: https://reviews.llvm.org/D96305
2021-02-08 19:41:01 -08:00
Greg McGary
87104faac4 [lld-macho] Add ARM64 target arch
This is an initial base commit for ARM64 target arch support. I don't represent that it complete or bug-free, but wish to put it out for review now that some basic things like branch target & load/store address relocs are working.

I can add more tests to this base commit, or add them in follow-up commits.

It is not entirely clear whether I use the "ARM64" (Apple) or "AArch64" (non-Apple) naming convention. Guidance is appreciated.

Differential Revision: https://reviews.llvm.org/D88629
2021-02-08 18:14:07 -07:00
Fangrui Song
830ead58fe [test] Fix unused check prefixes 2021-02-08 13:44:30 -08:00
Jez Ng
ac9dd247da [lld-macho] Try to make ubsan happy
Summary: We should avoid passing a null pointer to memcpy.
2021-02-08 14:51:36 -05:00
Jez Ng
5112035751 [lld-macho] Emit LSDA info in compact unwind
The LSDA pointers are encoded as offsets from the image base,
and arranged in one big contiguous array. Each second-level page records
the offset within that LSDA array which corresponds to the LSDA for its
first CU entry.

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D95810
2021-02-08 13:48:00 -05:00
Jez Ng
525bfa10ec [lld-macho] Emit personalities in compact unwind
Note that there is a triple indirection involved with
personalities and compact unwind:

1. Two bits of each CU encoding are used as an offset into the
   personality array.
2. Each entry of the personality array is an offset from the image base.
   The resulting address (after adding the image base) should point within the
   GOT.
3. The corresponding GOT entry contains the actual pointer to the
   personality function.

To further complicate things, when the personality function is in the
object file (as opposed to a dylib), its references in
`__compact_unwind` may refer to it via a section + offset relocation
instead of a symbol relocation. Since our GOT implementation can only
create entries for symbols, we have to create a synthetic symbol at the
given section offset.

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D95809
2021-02-08 13:47:59 -05:00
Fangrui Song
eea34aae2e [ELF] Inspect -EL & -EB for OUTPUT_FORMAT(default, big, little)
Choose big if -EB is specified, little if -EL is specified, or default if neither is specified.
The new behavior matches GNU ld.

Fixes: https://github.com/ClangBuiltLinux/linux/issues/1025

Differential Revision: https://reviews.llvm.org/D96214
2021-02-08 10:34:57 -08:00
Fangrui Song
7605a9a009 [ELF] Support aarch64_be
This patch adds

* Big-endian values for `R_AARCH64_{ABS,PREL}{16,32,64}` and `R_AARCH64_PLT32`
* aarch64elfb & aarch64linuxb BFD emulations
* elf64-bigaarch64 output format (bfdname)

Link: https://github.com/ClangBuiltLinux/linux/issues/1288

Differential Revision: https://reviews.llvm.org/D96188
2021-02-08 08:55:29 -08:00
Fangrui Song
980d28d955 ELFObjectWriter: Don't sort local symbols
GNU as does not sort local symbols. This has several advantages:

* The .symtab order is roughly the symbol occurrence order.
* The closest preceding STT_SECTION symbol is the definition of a local symbol.
* The closest preceding STT_FILE symbol is the defining file of a local symbol, if there are multiple default-version .file directives. (Not implemented in MC.)
2021-02-07 15:47:10 -08:00
Fangrui Song
4b5dbc7a3b [ELF][test] Improve aarch64 tests 2021-02-06 11:50:57 -08:00
Fangrui Song
6a1235211d [ELF] --gc-sections: collect unused SHF_LINK_ORDER .gcc_except_table
A SHF_LINK_ORDER .gcc_except_table is similar to a .gcc_except_table in
a section group. The associated text section is responsible for retaining it.

LLD still does not support GC of non-group non-SHF_LINK_ORDER .gcc_except_table -
but that is not necessary because we can teach the compiler to set SHF_LINK_ORDER.
2021-02-05 21:35:27 -08:00
Greg McGary
c3e4f3b231 [lld-macho] Fix alignment & layout to match ld64 and satisfy kernel & codesign
The Mach kernel & codesign on arm64 macOS has strict requirements for alignment and sequence of segments and sections. Dyld probably is just as picky, though kernel & codesign reject malformed Mach-O files before dyld ever has a chance.

I developed this diff by incrementally changing alignments & sequences to match the output of ld64. I stopped when my hello-world test program started working: `codesign --verify` succeded, and `execve(2)` didn't immediately fail with `errno == EBADMACHO` = `"Malformed Mach-O file"`.

Differential Revision: https://reviews.llvm.org/D94935
2021-02-05 17:22:03 -07:00
Fangrui Song
5f4d7b2f0a [ELF] Improve --icf=safe diagnostic
The current diagnostic has confused users. The new wording is adapted from one suggested by Ian Lance Taylor.

Differential Revision: https://reviews.llvm.org/D95917
2021-02-05 09:37:37 -08:00
Fangrui Song
ed399d508f [ELF] Make SHF_GNU_RETAIN sections GC roots
binutils 2.36 introduced the new section flag SHF_GNU_RETAIN (for ELFOSABI_GNU &
ELFOSABI_FREEBSD) to mark a sections as a GC root. Several LLVM side toolchain
folks (including me) were involved in the design process of SHF_GNU_RETAIN and
were happy with this proposal.

Currently GNU ld only respects SHF_GNU_RETAIN semantics for ELFOSABI_GNU &
ELFOSABI_FREEBSD object files
(https://sourceware.org/bugzilla/show_bug.cgi?id=27282).  GNU ld sets EI_OSABI
to ELFOSABI_GNU for relocatable output
(https://sourceware.org/bugzilla/show_bug.cgi?id=27091). In practice the single
value EI_OSABI is neither a good indicator for object file compatibility, nor a
useful mechanism marking used ELF extensions.

For input, we respect SHF_GNU_RETAIN semantics even for ELFOSABI_NONE object
files. This is compatible with how LLD and GNU ld handle (mildly useful) STT_GNU_IFUNC
/ (emitted by GCC, considered misfeature by some folks) STB_GNU_UNIQUE input.
(As of LLVM 12.0.0, the integrated assembler does not set ELFOSABI_GNU for
STT_GNU_IFUNC/STB_GNU_UNIQUE).
Arguably STT_GNU_IFUNC/STB_GNU_UNIQUE probably need indicators in object files
but SHF_GNU_RETAIN is more likely accepted by more OSABI platforms.

For output, we take a step further than GNU ld: we don't promote ELFOSABI_NONE
to ELFOSABI_GNU for all output.

Differential Revision: https://reviews.llvm.org/D95749
2021-02-04 09:23:01 -08:00
Fangrui Song
b3165a70ae [ELF] Allow R_386_GOTOFF from .debug_info
In GCC emitted .debug_info sections, R_386_GOTOFF may be used to
relocate DW_AT_GNU_call_site_value values
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98946).

R_386_GOTOFF (`S + A - GOT`) is one of the `isStaticLinkTimeConstant` relocation
type which is not PC-relative, so it can be used from non-SHF_ALLOC sections. We
current allow new relocation types as needs come. The diagnostic has caught some
bugs in the past.

Differential Revision: https://reviews.llvm.org/D95994
2021-02-04 09:17:47 -08:00
Jez Ng
ea5b75de49 [lld-macho] Try to fix Windows build 2021-02-03 16:05:23 -05:00
Jez Ng
2d2e0000d3 [lld-macho] Rename VERSION CONTROL to VERSION TARGETING in helptext
Per https://reviews.llvm.org/D94938#inline-896740.
2021-02-03 13:43:47 -05:00
Jez Ng
4b2169fb6b [lld-macho] Remove stray ehFrame change
Per https://reviews.llvm.org/D95121#inline-897943.
2021-02-03 13:43:47 -05:00
Jez Ng
f843bb82c0 [lld-macho] Force-loading should share code path with regular archive loads
This extends {D92539} to work even when we are loading archive
members via `-force_load`. I uncovered this issue while trying to
force-load archives containing bitcode -- we were segfaulting.

In addition to fixing the `-force_load` case, this diff also addresses
the behavior of `-ObjC` when LTO bitcode is involved -- we need to
force-load those archive members if they contain ObjC categories.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D95265
2021-02-03 13:43:47 -05:00
Jez Ng
163dcd8513 [lld-macho] Associate each Symbol with an InputFile
This makes our error messages more informative. But the bigger motivation is for
LTO symbol resolution, which will be in an upcoming diff. The changes in this
one are largely mechanical.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D94316
2021-02-03 13:43:47 -05:00
Abhina Sreeskantharajan
e59d336e75 [test] Use host platform specific error message substitution in lit tests - continued
On z/OS, other error messages are not matched correctly in lit tests.

```
EDC5121I Invalid argument.
EDC5111I Permission denied.
```

This patch adds a lit substitution to fix it.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D95808
2021-02-03 09:53:22 -05:00
Greg McGary
3a9d2f1488 [lld-macho][NFC] refactor relocation handling
Add per-reloc-type attribute bits and migrate code from per-target file into target independent code, driven by reloc attributes.

Many cleanups

Differential Revision: https://reviews.llvm.org/D95121
2021-02-02 10:54:53 -07:00
Fangrui Song
57bfa2ddb6 [ELF] Delete unused --warn-ifunc-textrel
The option catches incompatibility between `R_*_IRELATIVE` and DT_TEXTREL/DF_TEXTREL
before glibc 2.29. Newer glibc versions are more common nowadays and I don't
think this option has ever been used. Diagnosing this problem is also
straightforward by reading the stack trace.
2021-02-02 09:47:06 -08:00
Fangrui Song
3f8dda50cb [test] Fix unuses FileCheck prefixes in lld 2021-02-01 20:52:33 -08:00
Wouter van Oortmerssen
0d9b17d0ef [WebAssembly] fixed wasm64 data segment init exp not 64-bit
As defined in the spec:
https://github.com/WebAssembly/memory64/blob/master/proposals/memory64/Overview.md

Differential Revision: https://reviews.llvm.org/D95651
2021-02-01 11:32:50 -08:00
Fangrui Song
3949a3ed49 [ELF][test] Add --emit-relocs --gc-sections test for relocation section for a non-SHF_ALLOC section
This has been fixed by D89841.
2021-01-30 00:51:36 -08:00
Greg McGary
0ef25cf558 [lld-macho][NFC] Add new option group for versions
Coalesce all version control options into a group

Differential Revision: https://reviews.llvm.org/D94938
2021-01-29 22:27:41 -07:00
Christopher Tetreault
d3e8b9fdc0 Revert "[CMake] Actually require python 3.6 or greater"
There are builders that do not have python 3.6. Revert until this situation can be rectified

This reverts commit 0703b0753c.
2021-01-29 12:03:32 -08:00
Christopher Tetreault
0703b0753c [CMake] Actually require python 3.6 or greater
Previously, CMake would find any version of Python3. However, the project
claims to require 3.6 or greater, and 3.6 features are being used.

Reviewed By: yln

Differential Revision: https://reviews.llvm.org/D95635
2021-01-29 11:47:21 -08:00
Abhina Sreeskantharajan
42a21778f6 [test] Use host platform specific error message substitution in lit tests
On z/OS, the following error message is not matched correctly in lit tests.

```
EDC5129I No such file or directory.
```

This patch uses a lit config substitution to check for platform specific error messages.

Reviewed By: muiez, jhenderson

Differential Revision: https://reviews.llvm.org/D95246
2021-01-29 07:16:30 -05:00
Reid Kleckner
bacf9cf2c5 Revert "[PDB] Defer relocating .debug$S until commit time and parallelize it"
This reverts commit 1a9bd5b813.

I suspect that this patch may have caused https://crbug.com/1171438.
2021-01-28 13:17:27 -08:00
Sam Clegg
5c0164890c [lld][WebAssembly] Update comments mentioning legacy function names. NFC
The __wasm_apply_relocs function was split into two separate
functions as part of https://reviews.llvm.org/D93066 but these
comments were not correctly updated at the time.

Differential Revision: https://reviews.llvm.org/D95623
2021-01-28 08:52:14 -08:00
Teresa Johnson
1487747e99 [LTO] Prevent devirtualization for symbols dynamically exported
Identify dynamically exported symbols (--export-dynamic[-symbol=],
--dynamic-list=, or definitions needed to preempt shared objects) and
prevent their LTO visibility from being upgraded.
This helps avoid use of whole program devirtualization when there may
be overrides in dynamic libraries.

Differential Revision: https://reviews.llvm.org/D91583
2021-01-27 15:54:13 -08:00
Tom Stellard
5369517d20 Bump the trunk major version to 13
and clear the release notes.
2021-01-26 19:37:55 -08:00
Adhemerval Zanella
988cc0a083 [LLD][ELF][AArch64] Add support for R_AARCH64_LD64_GOTPAGE_LO15 relocation
It is not used by LLVM, but GCC might generates it when compiling
with -fpie, as indicated by PR#40357 [1].

[1] https://bugs.llvm.org/show_bug.cgi?id=40357
2021-01-26 12:01:38 +00:00
Georgii Rymar
e98d5c3192 [libObject,llvm-readelf/obj] - Don't use @@ when printing versions of undefined symbols.
A default version (@@) is only available for defined symbols.

Currently we use "@@" for undefined symbols too.
This patch fixes the issue and improves our test case.

Differential revision: https://reviews.llvm.org/D95219
2021-01-26 12:05:59 +03:00
Sam Clegg
84c6f32584 [Object][WebAssembly] Update format of error messages
Error message should start with lowercase in accordance with
https://llvm.org/docs/CodingStandards.html#error-and-warning-messages

Differential Revision: https://reviews.llvm.org/D95239
2021-01-25 21:12:53 -08:00
Jez Ng
3dd5ea9dd8 [lld-macho] Link against ObjCARCOpts instead of ObjCARC
Not sure what the difference is, but using the latter appears to cause
issues in standalone builds. See llvm.org/PR48853.

Reviewed By: #lld-macho, compnerd

Differential Revision: https://reviews.llvm.org/D95359
2021-01-25 19:01:48 -05:00
Sam Clegg
299b0e5ee9 [lld] Consistent help text for --save-temps
I noticed that this option was not appearing at all in the `--help`
messages for `wasm-ld` or `ld.lld`.

Add help text and make it consistent across all ports.

Differential Revision: https://reviews.llvm.org/D94925
2021-01-25 10:27:18 -08:00
Abhina Sreeskantharajan
978444d531 Revert "[SystemZ][z/OS] Fix No such file or directory expression error"
This reverts commit 06f8a49693.
2021-01-25 08:29:38 -05:00
James Henderson
b37a349ff2 [lld][ELF][test] Add testing for IE/LD TLS weak undef references
Whilst migrating/retiring some downstream testing, I came across a test
for weak undef IE and LD TLS references, but was unable to find any
equivalent in LLD's upstream testing. There does seem to be some slight
subtle differences that could be worth testing compared to LE TLS
references, in particular that IE can be relaxed to LE in this case,
hence this change.

Differential Revision: https://reviews.llvm.org/D95124

Reviewed by: grimar, MaskRay
2021-01-25 09:58:56 +00:00
Fangrui Song
6fe193bf27 [test] Add -mtriple 2021-01-22 19:07:02 -08:00
Fangrui Song
eda973bbc7 [ELF][test] Add a test about --exclude-libs applying to version symbols
D94280 also fixed PR48702.
2021-01-22 18:46:56 -08:00
Jez Ng
041f3ee664 [lld-macho] Ignore -lto_library
Just getting rid of some logspew as I test LLD under existing build
systems.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D95213
2021-01-22 16:48:50 -05:00
Hongtao Yu
8aa3ee241d [CSSPGO] LTO option for pseudo probe
Adding a lld option to support emitting pseudo probe metadata in LTO mode.

Reviewed By: MaskRay, wmi, wenlei

Differential Revision: https://reviews.llvm.org/D95056
2021-01-22 11:07:10 -08:00
Fangrui Song
d24b94f070 [ELF] --wrap: retain __wrap_foo if foo is defined in an object/bitcode file
If foo is referenced in any object file, bitcode file or shared object,
`__wrap_foo` should be retained as the redirection target of sym
(f96ff3c0f8).

If the object file defining foo has foo references, we cannot easily distinguish
the case from cases where foo is not referenced (we haven't scanned
relocations). Retain `__wrap_foo` because we choose to wrap sym references
regardless of whether sym is defined to keep non-LTO/LTO/relocatable links' behaviors similar
https://sourceware.org/bugzilla/show_bug.cgi?id=26358 .

If foo is defined in a shared object, `__wrap_foo` can still be omitted
(`wrap-dynamic-undef.s`).

Reviewed By: andrewng

Differential Revision: https://reviews.llvm.org/D95152
2021-01-22 09:20:29 -08:00