Commit Graph

13458 Commits

Author SHA1 Message Date
Peter Penzin e59726220f [LLD] [COFF] Align all debug directories
Match MSVC linker output - align all debug directories on four bytes,
while removing debug directory alignment. This would have the same
effect on CETCOMPAT support as D89919.

Chromium bug: https://crbug.com/1136664

Differential Revision: https://reviews.llvm.org/D89921
2020-11-02 10:47:51 -08:00
Fangrui Song 2fc704a0a5 [ELF] --emit-relocs: fix st_value of STT_SECTION in the presence of a gap before the first input section
In the presence of a gap, the st_value field of a STT_SECTION symbol is the
address of the first input section (incorrect if there is a gap). Set it to the
output section address instead.

In -r mode, this bug can cause an incorrect non-zero st_value of a STT_SECTION
symbol (while output sections have zero addresses, input sections may have
non-zero outSecOff).  The non-zero st_value can cause the final link to have
incorrect relocation computation (both GNU ld and LLD add st_value of the
STT_SECTION symbol to the output section address).

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D90520
2020-11-02 08:37:15 -08:00
Sam Clegg 1800b44651 [lld][WebAssembly] Remove bad-reloc test
This test was checking behaviour that only exists in the debug
configuration so will fail in release builds.

Perhaps there is way to keep this test around and only run
it in debug builds but for now I'm removing so fix the
release builders.

Differential Revision: https://reviews.llvm.org/D90542
2020-10-31 16:42:55 -07:00
Reid Kleckner 09662eeb46 Fix lld/wasm test portability issue, and XFAIL the test
I don't see any warnings from lld.wasm locally. Needs more
investigation.
2020-10-31 11:19:28 -07:00
Reid Kleckner 32cc962ef3 [COFF] Move ghash timers under the "add objects" timer
I had envisioned the ghash step as a big up front step, but as currently
written, the timers are nested, and we are notionally adding types from
objects, so we might as well arrange the timers this way.
2020-10-31 11:08:59 -07:00
Ali Tamur ca55c99d56 [lld][WebAssembly] Do not specify temporary file name in tests.
bad-reloc.yaml test introduced at 9d1409df87 uses a name (out.wasm) to specify a
temporary output file name, which causes breakage in our system.
2020-10-30 18:27:28 -07:00
Sam Clegg 9d1409df87 [lld][WebAssembly] Give better warnings on bad relocation sites
Differential Revision: https://reviews.llvm.org/D90443
2020-10-30 10:11:04 -07:00
Wouter van Oortmerssen b8c2d60df5 [WebAssembly] Improved LLD error messages in case of mixed wasm32/wasm64 object files
Differential Revision: https://reviews.llvm.org/D90428
2020-10-29 17:15:59 -07:00
Marcel Hlopko 9bb9b737c5 Remove HAVE_VCS_VERSION_INC, not needed
This preprocessor define was meant to be used to conditionally include VCSVersion.inc. However, the define was always set, and it was the content of the header that was conditionally generated. Therefore HAVE_VCS_VERSION_INC should be cleaned up.

Reviewed By: gribozavr2, MaskRay

Differential Revision: https://reviews.llvm.org/D84623
2020-10-29 13:09:05 -07:00
Fangrui Song ae73091f30 [ELF] -r: don't crash when a non-SHF_LINK_ORDER orphan is added before a SHF_LINK_ORDER orphan
Fixes https://github.com/ClangBuiltLinux/linux/issues/1186

If a non-SHF_LINK_ORDER orphan is added first, `firstIsec->flags & SHF_LINK_ORDER`
will be zero and we currently assert when calling `getLinkOrderDep`.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D90200
2020-10-28 08:56:42 -07:00
Sam Clegg 84129150ce [lld][WebAssembly] Fix memory size in dylink section for -pie exectuables
This field to represents the amount of static data needed by
an dynamic library or executable it should not include things
like heap or stack areas, which in the case of `-pie` are
not determined until runtime (e.g. __stack_pointer is imported).

Differential Revision: https://reviews.llvm.org/D90261
2020-10-27 16:05:52 -07:00
Benjamin Kramer 85e2af7ffe [lld][ELF] Don't write output to the test directory. NFC. 2020-10-26 18:10:31 +01:00
Fangrui Song 398b81067c [ELF] Don't crash on R_X86_64_GOTPCRELX for test/binop instructions
While MC did not produce R_X86_64_GOTPCRELX for test/binop instructions
(movl/adcl/addl/andl/...) before the previous commit, this code path has been
exercised by -fno-integrated-as for GNU as since 2016: -no-pie relaxing
may incorrectly access loc[-3] and produce a corrupted instruction.

Simply handle test/binop R_X86_64_GOTPCRELX like R_X86_64_GOTPCREL.
2020-10-24 15:14:17 -07:00
Fangrui Song 9267caebfa [ELF] Don't error on R_PPC64_REL24/R_PPC64_REL24_NOTOC referencing __tls_get_addr for missing R_PPC64_TLSGD/R_PPC64_TLSLD
This partially reverts D85994.

In glibc, elf/dl-sym.c calls the raw `__tls_get_addr` by specifying the
tls_index parameter. Such a call does not have a pairing R_PPC64_TLSGD/R_PPC64_TLSLD.
This is legitimate. Since we cannot distinguish the benign case from cases due
to toolchain issues, we have to be permissive.

Acked by Stefan Pintilie
2020-10-23 10:38:07 -07:00
Stefan Pintilie c6561ccfd9 [PowerPC][LLD] Support for PC Relative TLS for Local Dynamic
Add support to LLD for PC Relative Thread Local Storage for Local Dynamic.
This patch adds support for two relocations: R_PPC64_GOT_TLSLD_PCREL34 and
R_PPC64_DTPREL34.

The Local Dynamic code is:
```
pla r3, x@got@tlsld@pcrel        R_PPC64_GOT_TLSLD_PCREL34
bl __tls_get_addr@notoc(x@tlsld) R_PPC64_TLSLD
                                 R_PPC64_REL24_NOTOC
...
paddi r9, r3, x@dtprel           R_PPC64_DTPREL34
```

After relaxation to Local Exec:
```
paddi r3, r13, 0x1000
nop
...
paddi r9, r3, x@dtprel          R_PPC64_DTPREL34
```

Reviewed By: NeHuang, sfertile

Differential Revision: https://reviews.llvm.org/D87504
2020-10-23 08:23:56 -05:00
James Henderson 342040bf00 [lld][ELF][test] Add additional test coverage for LTO
These are all inspired by existing test coverage we have in an internal
testsuite.

Reviewed by: grimar, MaskRay

Differential Revision: https://reviews.llvm.org/D89775
2020-10-23 09:51:30 +01:00
Fangrui Song ce3c5dae06 [ELF] --warn-backrefs: save the referenced InputFile *
For a diagnostic `A refers to B` where B refers to a bitcode file, if the
symbol gets optimized out, the user may see `A refers to <internal>`; if the
symbol is retained, the user may see `A refers to lto.tmp`.

Save the reference InputFile * in the DenseMap so that the original filename is
available in reportBackrefs().
2020-10-22 15:27:19 -07:00
Fangrui Song a8f9f08018 [ELF] Set SHF_INFO_LINK for .rel[a].plt and .rel[a].dyn
The ELF spec says

> If the sh_flags field for this section header includes the attribute SHF_INFO_LINK, then this member represents a section header table index.

Set SHF_INFO_LINK so that binary manipulation tools know that sh_info is
a section header table index instead of (the number of local symbols in the case of SHT_SYMTAB/SHT_DYNSYM).
We have already added SHF_INFO_LINK for --emit-relocs retained SHT_REL[A].

For example, we can teach llvm-objcopy to preserve the section index of the sh_info referenced section if
SHF_INFO_LINK is set. (GNU objcopy recognizes .rel[a].plt and updates
sh_info even if SHF_INFO_LINK is not set).

Reviewed By: grimar, psmith

Differential Revision: https://reviews.llvm.org/D89828
2020-10-22 09:48:19 -07:00
Fangrui Song b6e4aae2cc [ELF] --gc-sections: retain dependent sections of non-SHF_ALLOC sections
Fix http://lists.llvm.org/pipermail/llvm-dev/2020-October/145908.html

Currently non-SHF_ALLOC SHT_REL[A] (due to --emit-relocs) and SHF_LINK_ORDER are not
marked live.

Reviewed By: grimar, psmith

Differential Revision: https://reviews.llvm.org/D89841
2020-10-21 10:11:26 -07:00
Sylvestre Ledru 0784e17f1b Remove .svn from exclude list as we moved to git
Reviewed By: emaste

Differential Revision: https://reviews.llvm.org/D89859
2020-10-21 16:09:21 +02:00
Fangrui Song 38b632c16e [ELF] --gdb-index: support --icf={safe,all}
The combination has not been tested before. In the case of ICF,
`e.section->getVA(0)` equals the start address of the output section.

This can cause incorrect overlapping with the actual function at the
start of the output section and potentially trigger a GDB internal error
in `dw2_find_pc_sect_compunit_symtab` (presumably because:
if a short address range incorrectly starts at the start address of the
output section, GDB may pick it instead of the correct longer address
range. When mapping an address within the long address range but
out of the scope of the short address range, the routine may find
nothing - while the code asserts that it can find something).

Note that in the case of ICF there may be duplicate address range entries,
but GDB appears to be fine with them.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D89751
2020-10-20 09:35:32 -07:00
Georgii Rymar 6487ffafd1 Reland "[yaml2obj][ELF] - Simplify the code that performs sections validation."
This reverts commit 1b589f4d4d and relands the D89463
with the fix: update `MappingTraits<FileFilter>::validate()` in ClangTidyOptions.cpp to
match the new signature (change the return type to "std::string" from "StringRef").

Original commit message:

This:

Changes the return type of MappingTraits<T>>::validate to std::string
instead of StringRef. It allows to create more complex error messages.

It introduces std::vector<std::pair<StringRef, bool>> getEntries():
a new virtual method of Section, which is the base class for all sections.
It returns names of special section specific keys (e.g. "Entries") and flags that says if them exist in a YAML.
The code in validate() uses this list of entries descriptions to generalize validation.
This approach was discussed in the D89039 thread.

Differential revision: https://reviews.llvm.org/D89463
2020-10-20 16:25:33 +03:00
Georgii Rymar 1b589f4d4d Revert "[yaml2obj][ELF] - Simplify the code that performs sections validation."
This reverts commit b9e2b59680.
2020-10-20 15:16:56 +03:00
Georgii Rymar b9e2b59680 [yaml2obj][ELF] - Simplify the code that performs sections validation.
This:
1) Changes the return type of `MappingTraits<T>>::validate` to `std::string`
instead of `StringRef`. It allows to create more complex error messages.

2) It introduces std::vector<std::pair<StringRef, bool>> getEntries():
a new virtual method of Section, which is the base class for all sections.
It returns names of special section specific keys (e.g. "Entries") and flags that
says if them exist in a YAML. The code in validate() uses this list of entries
descriptions to generalize validation.
This approach was discussed in the D89039 thread.

Differential revision: https://reviews.llvm.org/D89463
2020-10-20 11:28:23 +03:00
Martin Storsjö 3785a413fe Reapply [LLD] [COFF] Implement a GNU/ELF like -wrap option
Add a simple forwarding option in the MinGW frontend, and implement
the private -wrap option in the COFF linker.

The feature in lld-link isn't gated by the -lldmingw option, but
the option is left as a private, undocumented option primarily
used by the MinGW driver.

The implementation is significantly based on the support for --wrap
in the ELF linker, but many small nuance details are different
between the ELF and COFF linkers, ending up with more than a few
implementation differences.

This fixes https://bugs.llvm.org/show_bug.cgi?id=47384.

Differential Revision: https://reviews.llvm.org/D89004

Reapplied with the bitfield member canInline fixed so it doesn't break
builds targeting windows.
2020-10-15 22:14:02 +03:00
Arthur Eubanks 3d338f6813 Revert "[LLD] [COFF] Implement a GNU/ELF like -wrap option"
This reverts commit a012c704b5.

Breaks Windows builds.

C:\src\llvm-mint\lld\COFF\Symbols.cpp(26,1): error: static_assert failed due to requirement 'sizeof(lld::coff::SymbolUnion) <= 48' "symbols should be optimized for memory usage"
static_assert(sizeof(SymbolUnion) <= 48,
2020-10-15 10:27:25 -07:00
Martin Storsjö a012c704b5 [LLD] [COFF] Implement a GNU/ELF like -wrap option
Add a simple forwarding option in the MinGW frontend, and implement
the private -wrap option in the COFF linker.

The feature in lld-link isn't gated by the -lldmingw option, but
the option is left as a private, undocumented option primarily
used by the MinGW driver.

The implementation is significantly based on the support for --wrap
in the ELF linker, but many small nuance details are different
between the ELF and COFF linkers, ending up with more than a few
implementation differences.

This fixes https://bugs.llvm.org/show_bug.cgi?id=47384.

Differential Revision: https://reviews.llvm.org/D89004
2020-10-15 18:34:02 +03:00
Martin Storsjö 9803cf57d6 [LLD] [COFF] Fix a condition that was missed in 7f0e6c31c2. NFC.
This should fix cases when e.g. auto import is enabled without
mingw mode in total being enabled.

Differential Revision: https://reviews.llvm.org/D89006
2020-10-15 18:34:01 +03:00
Andrew Ng 88ce27c39c [LLD][ELF] Improve ICF for relocations to ineligible sections via "aliases"
ICF was not able to merge equivalent sections because of relocations to
sections ineligible for ICF that use alternative symbols, e.g. symbol
aliases or section relative relocations.

Merging in this scenario has been enabled by giving the sections that
are ineligible for ICF a unique ID, i.e. an equivalence class of their
own. This approach also provides another benefit as it improves the
hashing that is used to perform the initial equivalance grouping for
ICF. This is because the ICF ineligible sections can now contribute a
unique value towards the hashes instead of the same value of zero. This
has been seen to reduce link time with ICF by ~68% for objects compiled
with -fprofile-instr-generate.

In order to facilitate this use of a unique ID, the existing
inconsistent approach to the setting of the InputSection eqClass in ICF
has been changed so that there is a clear distinction between the
eqClass values of ICF eligible sections and those of the ineligible
sections that have a unique ID. This inconsistency could have caused
incorrect equivalence class equality in the past, although it appears
that no issues were encountered in actual use.

Differential Revision: https://reviews.llvm.org/D88830
2020-10-15 12:43:14 +01:00
Luqman Aden 6a73d6564a [LLD] Set alignment as part of Characteristics in TLS table.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46473

LLD wasn't previously specifying any specific alignment in the TLS table's Characteristics field so the loader would just assume the default value (16 bytes). This works most of the time except if you have thread locals that want specific higher alignments (e.g. 32 as in the bug) *even* if they specify an alignment on the thread local. This change updates LLD to take the max alignment from tls section.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D88637
2020-10-15 00:22:40 -07:00
Luqman Aden f87c98def8 Revert "[LLD] Set alignment as part of Characteristics in TLS table."
Revert individual wip commits and will instead follow up with a
single commit with all the changes. Makes cherry-picking easier
and will contain all the right tags.

This reverts commit 32a4ad3b6c.
This reverts commit 7fe13af676.
This reverts commit 51fbc1bef6.
This reverts commit f80950a8bb.
This reverts commit 0778cad9f3.
This reverts commit 8b70d527d7.
2020-10-15 00:21:36 -07:00
Luqman Aden 32a4ad3b6c [LLD] Set alignment as part of Characteristics in TLS table.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46473

LLD wasn't previously specifying any specific alignment in the TLS table's Characteristics field so the loader would just assume the default value (16 bytes). This works most of the time except if you have thread locals that want specific higher alignments (e.g. 32 as in the bug) *even* if they specify an alignment on the thread local. This change updates LLD to take the max alignment from tls section.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D88637
2020-10-14 19:41:03 -07:00
Luqman Aden 7fe13af676 Nit: Use early return to reduce indentation. 2020-10-14 19:34:32 -07:00
Luqman Aden f80950a8bb Update tests. 2020-10-14 19:34:32 -07:00
Luqman Aden 8b70d527d7 [LLD] Set alignment as part of Characteristics in TLS table.
Differential Revision: https://reviews.llvm.org/D88637
2020-10-14 19:34:31 -07:00
Konstantin Zhuravlyov 3fdf3b1539 AMDGPU: Update AMDHSA code object version handling
Differential Revision: https://reviews.llvm.org/D89076
2020-10-14 13:04:27 -04:00
jasonliu f85bcc21dd [AIX] Turn -fdata-sections on by default in Clang
Summary:

This patch does the following:
1. Make InitTargetOptionsFromCodeGenFlags() accepts Triple as a
 parameter, because some options' default value is triple dependant.
2. DataSections is turned on by default on AIX for llc.
3. Test cases change accordingly because of the default behaviour change.
4. Clang Driver passes in -fdata-sections by default on AIX.

Reviewed By: MaskRay, DiggerLin

Differential Revision: https://reviews.llvm.org/D88737
2020-10-14 15:58:31 +00:00
Luqman Aden dc128e5968 [test][lld] Mark TLS tests as REQUIRES: x86.
Fixes http://lab.llvm.org:8011/#/builders/119/builds/92
2020-10-14 00:29:06 -07:00
Luqman Aden 6b7738e204 [LLD] Add baseline test for TLS alignment. NFC.
Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D88646
2020-10-13 20:53:32 -07:00
Alexandre Ganea 617d64f6c5 Re-land [ThinLTO] Re-order modules for optimal multi-threaded processing
This reverts 9b5b305023 and fixes the unwanted re-ordering when generating ThinLTO indexes.

The goal of this patch is to better balance thread utilization during ThinLTO in-process linking (in llvm-lto2 or in LLD). Before this patch, large modules would often be scheduled late during execution, taking a long time to complete, thus starving the thread pool.

We now sort modules in descending order, based on each module's bitcode size, so that larger modules are processed first. By doing so, smaller modules have a better chance to keep the thread pool active, and thus avoid starvation when the bitcode compilation is almost complete.

In our case (on dual Intel Xeon Gold 6140, Windows 10 version 2004, two-stage build), this saves 15 sec when linking `clang.exe` with LLD & -flto=thin, /opt:lldltojobs=all, no ThinLTO cache, -DLLVM_INTEGRATED_CRT_ALLOC=d:\git\rpmalloc.

Before patch: 100 sec
After patch: 85 sec

Inspired by the work done by David Callahan in D60495.

Differential Revision: https://reviews.llvm.org/D87966
2020-10-13 21:54:15 -04:00
Andrew Paverd cfd8481da1 Reland [CFGuard] Add address-taken IAT tables and delay-load support
This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D87544
2020-10-13 13:20:52 -07:00
Konstantin Zhuravlyov f218652a36 LLD/AMDGPU: Infer os abi based on input llvm bitcode
Differential Revision: https://reviews.llvm.org/D89042
2020-10-13 12:20:28 -04:00
Paulo Matos 388fb67b0d [WebAssembly] Added .tabletype to asm and multiple table support in obj files
Adds more testing in basic-assembly.s and a new test tables.s.
Adds support to yaml reading and writing of tables as well.

Differential Revision: https://reviews.llvm.org/D88815
2020-10-13 07:52:23 -07:00
Sam Clegg b3b4cda104 [lld][WebAssembly] Don't GC library objects under `--whole-archive`
Followup on https://reviews.llvm.org/D85062 which ignores
entire library objects when no symbols are used within them.
This is shouldn't apply with `--whole-archive` since this
is specified to treat them like direct object inputs.

Differential Revision: https://reviews.llvm.org/D89290
2020-10-12 21:19:19 -07:00
Dan Gohman 950ae43091 [WebAssembly] GC constructor functions in otherwise unused archive objects
This allows `__wasilibc_populate_libpreopen` to be GC'd in more cases
where it isn't needed, including when linked from Rust's libstd.

Differential Revision: https://reviews.llvm.org/D85062
2020-10-12 18:54:57 -07:00
Sam Clegg 2513407d39 [lld][WebAssembly] Add support for -Bsymbolic flag
This flag works in a similar way to the ELF linker in that it
will resolve any defined symbols to their local definition with
a shared library or -pie executable.

This flag has no effect on static linking.

Differential Revision: https://reviews.llvm.org/D89152
2020-10-12 17:25:04 -07:00
Martin Storsjö d77d727339 [LLD] [COFF] Fix a ubsan error in pdb-type-server-missing.yaml
This error has been present since 5519e4da83.

Differential Revision: https://reviews.llvm.org/D89027
2020-10-12 23:28:23 +03:00
Christian Iversen a9cefc3dee [ELF] Fix broken bitstream linking with lld when e_machine > 255
In ELF/InputFiles.cpp, getBitcodeMachineKind() is limited to uint8_t return
type. This works as long as EM_xxx is < 256, which is true for common
architectures, but not for some newly assigned or unofficial EM_* values.

The corresponding ELF field (e_machine) can hold uint16_t.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D89185
2020-10-11 14:19:25 -07:00
Martin Storsjö 1dbfd87319 [LLD] [ELF] Fix the help listing for the wrap option. NFC.
This option just takes a single symbol name per invocation of the
option.

Differential Revision: https://reviews.llvm.org/D89007
2020-10-09 15:32:00 +03:00
Fangrui Song db1988f038 [ELF] Don't change binding to STB_WEAK for an undefined specified by -u
Similar to D66992.
In GNU ld, a -u specified symbol is a STB_DEFAULT undefined.
It cannot be changed to STB_WEAK by a later STB_WEAK undefined in a regular object file.

The behavior is consistent with our model because -u means "we need to fetch a lazy definition".
It should not be altered just because there is also a STB_WEAK undefined.

Note, our -u semantics are still different from GNU ld (https://github.com/ClangBuiltLinux/linux/issues/515):
we don't force the specified symbol to appear in .symtab This is a deliberate decision.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D88945
2020-10-08 08:31:34 -07:00